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1
Duncan, W. Colin. "The inadequate corpus luteum." Reproduction and Fertility 2, no. 1 (February 26, 2021): C1—C7. http://dx.doi.org/10.1530/raf-20-0044.
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The corpus luteum is the source of progesterone in the luteal phase of the cycle and the initial two-thirds of the first trimester of pregnancy. Normal luteal function is required for fertility and the maintenance of pregnancy. Progesterone administration is increasingly used during fertility treatments and in early pregnancy to mitigate potentially inadequate corpus luteum function. This commentary considers the concept of the inadequate corpus luteum and the role and effects of exogenous progesterone. Progesterone supplementation does have important beneficial effects but we should be wary of therapeutic administration beyond or outside the evidence base. Lay summary After an egg is released a structure is formed on the ovary called a corpus luteum (CL). This produces a huge amount of a hormone called progesterone. Progesterone makes the womb ready for pregnancy but if a pregnancy does not happen the CL disappears after 12–14 days and this causes a period. If a pregnancy occurs, then the pregnancy hormone (hCG) keeps the CL alive and its progesterone supports the pregnancy for the next 6–8 weeks until the placenta takes over and the corpus luteum disappears. That means that if the CL is not working correctly there could be problems getting pregnant or staying pregnant. If a CL is not producing enough progesterone it usually means there is a problem with the growing or releasing of the egg and treatment should focus on these areas. In IVF cycles, where normal hormones are switched off, the CL does not produce quite enough progesterone before the pregnancy test and extra progesterone is needed at this time. In recurrent or threatened miscarriage, however, there is not any evidence that the CL is not working well or progesterone is low. However, there is benefit in taking extra progesterone if there is bleeding in early pregnancy in women with previous miscarriages. This might be because of the effects of high-dose progesterone on the womb or immune system. As changes to the hormone environment in pregnancy may have some life-long consequences for the offspring we have to be careful only to give extra progesterone when we are sure it is needed.
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Niswender, Gordon D., Jennifer L. Juengel, Patrick J. Silva, M. Keith Rollyson, and Eric W. McIntush. "Mechanisms Controlling the Function and Life Span of the Corpus Luteum." Physiological Reviews 80, no. 1 (January 1, 2000): 1–29. http://dx.doi.org/10.1152/physrev.2000.80.1.1.
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The primary function of the corpus luteum is secretion of the hormone progesterone, which is required for maintenance of normal pregnancy in mammals. The corpus luteum develops from residual follicular granulosal and thecal cells after ovulation. Luteinizing hormone (LH) from the anterior pituitary is important for normal development and function of the corpus luteum in most mammals, although growth hormone, prolactin, and estradiol also play a role in several species. The mature corpus luteum is composed of at least two steroidogenic cell types based on morphological and biochemical criteria and on the follicular source of origin. Small luteal cells appear to be of thecal cell origin and respond to LH with increased secretion of progesterone. LH directly stimulates the secretion of progesterone from small luteal cells via activation of the protein kinase A second messenger pathway. Large luteal cells are of granulosal cell origin and contain receptors for PGF2αand appear to mediate the luteolytic actions of this hormone. If pregnancy does not occur, the corpus luteum must regress to allow follicular growth and ovulation and the reproductive cycle begins again. Luteal regression is initiated by PGF2αof uterine origin in most subprimate species. The role played by PGF2αin primates remains controversial. In primates, if PGF2αplays a role in luteolysis, it appears to be of ovarian origin. The antisteroidogenic effects of PGF2αappear to be mediated by the protein kinase C second messenger pathway, whereas loss of luteal cells appears to follow an influx of calcium, activation of endonucleases, and an apoptotic form of cell death. If the female becomes pregnant, continued secretion of progesterone from the corpus luteum is required to provide an appropriate uterine environment for maintenance of pregnancy. The mechanisms whereby the pregnant uterus signals the corpus luteum that a conceptus is present varies from secretion of a chorionic gonadotropin (primates and equids), to secretion of an antiluteolytic factor (domestic ruminants), and to a neuroendocrine reflex arc that modifies the secretory patterns of hormones from the anterior pituitary (most rodents).
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Bramley, T. A., G. S. Menzies, A. S. McNeilly, and H. G. Friesen. "Receptors for lactogenic hormones in the ovine corpus luteum. I: A major discrepancy in the specific binding of radiolabelled ovine prolactin and human growth hormone." Journal of Endocrinology 113, no. 3 (June 1987): 365–74. http://dx.doi.org/10.1677/joe.0.1130365.
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ABSTRACT The characteristics of the binding of 125I-labelled human GH (hGH) and ovine prolactin (oPRL) were studied in the ovine corpus luteum. Although oPRL is the homologous ligand for sheep lactogenic receptors, its binding was significantly and consistently lower than that of 125I-labelled hGH. This was not due to iodination damage of oPRL since: (1) 125I-labelled oPRL tracers which bound poorly relative to 125I-labelled hGH in the ovine corpus luteum were equipotent in the pig and rat corpus luteum, (2) the differences between 125I-labelled hGH and oPRL binding persisted with tracers of equivalent biopotency and (3) the iodination procedure affected neither oPRL bioactivity in the Nb2 tumour assay nor its binding activity with ovine corpus luteum receptors. Ovine luteal receptors were specific for lactogenic hormones. The specific binding of 125I-labelled hGH or oPRL could be inhibited completely by incubation with either unlabelled hormone, with similar potencies. However, oGH inhibited binding only at much higher concentrations, consistent with its known contamination with oPRL. Moreover, 125I-labelled oGH was not bound specifically to sheep luteal tissue. Fractionation of sheep luteal homogenates on sucrose density gradients (with or without cell-surface membrane perturbation by digitonin) demonstrated that binding of 125I-labelled hGH and 125I-labelled oPRL peaked in the same regions of the gradients, coincident with a number of luteal cell-surface membrane markers. We conclude that the marked discrepancy between the binding of hGH and oPRL tracers by sheep luteal tissue was not due to iodination damage of oPRL, binding of 125I-labelled hGH to somatogenic receptors or differential binding to luteal cell-surface versus intracellular receptors. J. Endocr. (1987) 113, 365–374
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Gemmell, RT. "A comparative study of the corpus luteum." Reproduction, Fertility and Development 7, no. 3 (1995): 303. http://dx.doi.org/10.1071/rd9950303.
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The corpus luteum (CL) is a transitory organ which has a regulatory role in reproduction. Sharks, amphibians and reptiles have corpora lutea that produce progesterone which influences the rate of embryonic development. The egg-laying monotremes and the two major mammalian groups, eutherian and marsupial, have a CL that secretes progesterone. Most eutherians have allowed for the uterine development of their young by extending the length of the oestrous cycle and the CL or placenta actively secretes progesterone until birth. Gestation in the marsupial does not extend beyond the length of an oestrous cycle and the major part of fetal development takes place in the pouch. Where the extension of the post-luteal phase in the eutherian has allowed for the uterine development of young, the marsupial has extended the pre-luteal phase of the oestrous cycle and has evolved an alternative reproductive strategy, embryonic diapause. The mechanism for the secretion of hormones from the CL has been controversial for many years. Densely-staining secretory granules have been observed in the CL of sharks, marsupials and eutherians. These granules have been reported to contain relaxin, oxytocin or mesotocin, and progesterone. A hypothesis to suit all available data is that all hormones secreted by the CL are transported within such granules. In conclusion, although there are obvious differences in the mode of reproduction in the two main mammalian groups, it is apparent that there is a great deal of similarity in the hormonal control of regression of the CL and parturition.
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Bramley, T. A., and G. S. Menzies. "Receptors for lactogenic hormones in the porcine corpus luteum: properties and luteal phase concentrations." Journal of Endocrinology 113, no. 3 (June 1987): 355–64. http://dx.doi.org/10.1677/joe.0.1130355.
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ABSTRACT Homogenates of pig corpora lutea contained specific, high-affinity receptors for ovine prolactin (oPRL) and human GH (hGH). Specific hormone binding was enhanced by divalent metal ions, but only when included in the binding reaction. Divalent metal ions did not act by increasing the recovery of bound hormone by low-speed centrifugation, but appeared to promote the formation of a more stable hormone– receptor complex. Both oPRL and hGH tracers were bound in similar amounts and with similar affinities by pig luteal homogenates and the concentrations of either unlabelled hormone required to displace specific binding of either tracer by 50% were identical. In contrast, 125I-labelled oGH failed to bind to pig luteal homogenates and oGH competed poorly for hGH or oPRL binding. Only hormones with prolactin-like activity competed for 125I-labelled oPRL binding. Specific prolactin binding was low in recently ovulated and early luteal phase corpora lutea, increased significantly in the mid-luteal phase and declined once more in the late luteal phase. Receptor concentrations increased with increasing gestational age. J. Endocr. (1987) 113, 355–364
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Yang, Ya-Li, Li-Rong Ren, Li-Feng Sun, Chen Huang, Tian-Xia Xiao, Bao-Bei Wang, Jie Chen, Brian A. Zabel, Peigen Ren, and Jian V. Zhang. "The role of GPR1 signaling in mice corpus luteum." Journal of Endocrinology 230, no. 1 (July 2016): 55–65. http://dx.doi.org/10.1530/joe-15-0521.
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Chemerin, a chemokine, plays important roles in immune responses, inflammation, adipogenesis, and carbohydrate metabolism. Our recent research has shown that chemerin has an inhibitory effect on hormone secretion from the testis and ovary. However, whether G protein-coupled receptor 1 (GPR1), the active receptor for chemerin, regulates steroidogenesis and luteolysis in the corpus luteum is still unknown. In this study, we established a pregnant mare serum gonadotropin-human chorionic gonadotropin (PMSG-hCG) superovulation model, a prostaglandin F2α (PGF2α) luteolysis model, and follicle and corpus luteum culture models to analyze the role of chemerin signaling through GPR1 in the synthesis and secretion of gonadal hormones during follicular/luteal development and luteolysis. Our results, for the first time, show that chemerin and GPR1 are both differentially expressed in the ovary over the course of the estrous cycle, with highest levels in estrus and metestrus. GPR1 has been localized to granulosa cells, cumulus cells, and the corpus luteum by immunohistochemistry (IHC). In vitro, we found that chemerin suppresses hCG-induced progesterone production in cultured follicle and corpus luteum and that this effect is attenuated significantly by anti-GPR1 MAB treatment. Furthermore, when the phosphoinositide 3-kinase (PI3K) pathway was blocked, the attenuating effect of GPR1 MAB was abrogated. Interestingly, PGF2α induces luteolysis through activation of caspase-3, leading to a reduction in progesterone secretion. Treatment with GPR1 MAB blocked the PGF2α effect on caspase-3 expression and progesterone secretion. This study indicates that chemerin/GPR1 signaling directly or indirectly regulates progesterone synthesis and secretion during the processes of follicular development, corpus luteum formation, and PGF2α-induced luteolysis.
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Auletta, F. J., D. S. C. Jones, and A. P. F. Flint. "Does the human corpus luteum synthesize neurohypophysial hormones?" Journal of Endocrinology 116, no. 2 (February 1988): 163–65. http://dx.doi.org/10.1677/joe.0.1160163.
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Thordarson, G., S. Galosy, G. O. Gudmundsson, B. Newcomer, R. Sridaran, and F. Talamantes. "Interaction of Mouse Placental Lactogens and Androgens in Regulating Progesterone Release in Cultured Mouse Luteal Cells." Endocrinology 138, no. 8 (August 1, 1997): 3236–41. http://dx.doi.org/10.1210/endo.138.8.5309.
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Abstract Pituitary hormones are essential for the maintenance of the corpus luteum in the pregnant mouse during the first half of gestation. Thereafter, hormones from the placenta take over the luteotropic role of the pituitary hormones. Mouse placental lactogen-I (mPL-I) and mPL-II, two PRL-like hormones produced in the placenta, are probably necessary for the maintenance of the corpus luteum in the latter half of pregnancy. A culture system of luteal cells from pregnant mice was developed to investigate the role of hormones from the placenta that may be important for the function of the corpus luteum. Mice were killed on days 10, 14, and 18 of pregnancy, and the corpora lutea were excised from the ovaries and digested in 0.1% collagenase, 0.002% DNase for 1 h. The resulting luteal cell suspension was plated onto 96-well plates coated with fibronectin (1 × 105 cells/well) and cultured for 1–3 days. Medium was changed daily. The cells were treated with various concentrations and combinations of mPL-I, mPL-II, mouse PRL, androstenedione, dihydrotestosterone, 17β-estradiol (E2), testosterone, hydroxyflutamide, cycloheximide, actinomycin D, and fadrozole to study the effects of these different treatments on progesterone (P4) production. The three lactogens (mPL-I, mPL-II, and mouse PRL) all stimulated the release of P4 from the luteal cells. The potency of the lactogens was similar and did not depend on the stage of pregnancy at which the luteal tissue was obtained. However, the responsiveness of the cells to all hormone-stimulated P4 release was gradually reduced the later in pregnancy the tissue was collected. Androgens also stimulated the release of P4 from the luteal cells, and when administered together, the lactogens and the androgens acted synergistically to stimulate P4 release. The androgens acted directly but not through conversion to E2, as determined by the findings that 1) the effects of the androgens could not be reproduced by E2 administration, 2) nonaromatizable androgen dihydrotestosterone was as effective as aromatizable androgens, and 3) aromatase inhibitor did not prevent the action of the androgens to stimulate the P4 release. The effect of the androgens on the P4 release was rapid, occurring within 15 min of hormone administration. It was not prevented by inhibitors of protein and RNA synthesis, and the intracellular androgen receptor antagonist hydroxyflutamide did not affect the androgen action. Therefore, the androgen effects were not mediated through the intracellular androgen receptor and de novo protein synthesis was not needed for androgen-stimulated P4 release.
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Hearn, J. P., and G. E. Webley. "Regulation of the corpus luteum of early pregnancy in the marmoset monkey: local interactions of luteotrophic and luteolytic hormones in vivo and their effects on the secretion of progesterone." Journal of Endocrinology 114, no. 2 (August 1987): 231–39. http://dx.doi.org/10.1677/joe.0.1140231.
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ABSTRACT The interaction between luteotrophic and luteolytic agents in controlling progesterone production by the marmoset corpus luteum in the late luteal phase/early pregnancy was investigated at the local level in vivo using a perfusion cannula system. Perfusion of the prostaglandin F2α(PGF2α) analogue, cloprostenol (0·5 μg/ml), resulted in an immediate fall in progesterone production. This response was not sustained in two out of five corpora lutea but pregnancy was terminated in all animals exposed to PGF2α. Perfusion of human chorionic gonadotrophin (hCG) (4 μg/ml) alone significantly stimulated progesterone secretion but there was no response to hCG when the corpus luteum had previously been perfused with PGF2α. Perfusion with hCG together with PGF2α prevented a fall in progesterone secretion. The results suggest that the luteolytic action of PGF2α in the marmoset may be to prevent luteotrophic support of the corpus luteum. Melatonin (860 pmol/l), perfused either with PGF2α or after PGF2α, stimulated progesterone production. The ability of melatonin to influence progesterone production by the primate corpus luteum may therefore be by both a direct luteotrophic action and the prevention of luteolysis. Application of the perfusion system in order to investigate the ability of deglycosylated hCG to antagonize the action of hCG at the corpus luteum showed the necessity of testing pure preparations of hormones. J. Endocr. (1987) 114, 231–239
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Journal, Baghdad Science. "The effect of aqueous crude extract of ginger on the histology of corpus luteum and the concentration of hormones estrogen and progesterone in pregnant mice." Baghdad Science Journal 12, no. 4 (December 6, 2015): 638–44. http://dx.doi.org/10.21123/bsj.12.4.638-644.
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This study was designed to investigate the effect of aqueous extract of ginger Zingiber officinale Roscoe on the histology of corpus luteum and the concentration of the hormones progesterone and estrogen during the first trimester of pregnancy (0 - 7) days from fertilization. 30 pregnant mice were divided into five experimental groups: control group (administrated with distilled water), and four groups treated at doses (284, 568, 1136,1420 mg / kg), orally administrated , daily with (0.1 ml). Microscopic examination results have shown histopathological changes in corpus luteum included: Pyknosis in some nuclei of granulosa cells, Karyorrhexis, Karyolysis in some granulosa cells, and necrosis in corpus luteum, with additional significant decrease in the average of diameters of corpus luteum at level (P
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Bramley, T. A., D. Stirling, I. A. Swanston, G. S. Menzies, and D. T. Baird. "Specific binding sites for LH/chorionic gonadotrophin, low-density lipoprotein, prolactin and FSH in homogenates of human corpus luteum. I: Validation of methods." Journal of Endocrinology 113, no. 2 (May 1987): 305–15. http://dx.doi.org/10.1677/joe.0.1130305.
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ABSTRACT The specific binding of 125I-labelled human chorionic gonadotrophin (hCG), human low-density lipoprotein (hLDL), human FSH (hFSH) and human prolactin (hPRL) to homogenates of human corpus luteum tissue was measured. Specific binding of 125I-labelled hCG was dependent on the temperature and duration of incubation, was inhibited by divalent metal ions or chelating agents, and increased linearly with homogenate concentration. Recovery of bound hormone was more effective using Millipore filtration or polyethylene glycol precipitation compared with centrifugation alone. Binding of 125I-labelled hCG was inhibited specifically by low levels of hCG and human LH (hLH) but not by ovine LH or bovine LH. Incubation of human luteal tissue with ice-cold citrate buffer (pH 3) released more than 90% of specifically bound 125I-labelled hCG within 5 min. This treatment inactivated LH receptors, but did not affect the immunoactivity of hLH released, enabling the measurement of released hormone by radioimmunoassay. Scatchard plots of binding of 125I-labelled LDL to human corpus luteum demonstrated a single class of binding sites. Binding was saturable, increased linearly with increasing concentration of homogenate, and was displaceable by low concentrations of unlabelled LDL. Binding of 125I-labelled hPRL to human luteal homogenates was increased by Mg2+ and was specific for lactogenic hormones (human prolactin, human growth hormone and ovine prolactin). Binding of 125I-labelled hFSH was not dependent on divalent metal ion concentration (in marked contrast to hFSH binding to immature pig granulosa cell receptors) and was displaced by hFSH preparations but not by hPRL, ovine LH or hCG at 1 μg/ml. These results establish optimal conditions and hormone specificities for the measurement of human luteal gonadotrophin and LDL receptors, and methods for the estimation of hLH/hCG endogenously bound to human corpus luteum tissue. J. Endocr. (1987) 113, 305–315
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Billhaq, Dody Houston, and Seunghyung Lee. "The Role of the Guanosine Nucleotide-Binding Protein in the Corpus Luteum." Animals 11, no. 6 (May 24, 2021): 1524. http://dx.doi.org/10.3390/ani11061524.
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The corpus luteum is a temporary endocrine gland in the ovary. In the ovarian cycle, repeated patterns of specific cellular proliferation, differentiation, and transformation occur that accompany the formation and regression of the corpus luteum. Molecular mechanism events in the ovarian microenvironment, such as angiogenesis and apoptosis, are complex. Recently, we focused on the role of RAS protein in the ovarian corpus luteum. RAS protein plays a vital role in the modulation of cell survival, proliferation, and differentiation by molecular pathway signaling. Additionally, reproductive hormones regulate RAS activity in the cellular physiological function of ovarian follicles during pre-ovulatory maturation and ovulation. Thus, we have reviewed the role of RAS protein related to the biological events of the corpus luteum in the ovary.
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Roberto da Costa, R. P., V. Branco, P. Pessa, J. Robalo Silva, and G. Ferreira-Dias. "Progesterone receptors and proliferating cell nuclear antigen expression in equine luteal tissue." Reproduction, Fertility and Development 17, no. 6 (2005): 659. http://dx.doi.org/10.1071/rd05024.
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Steroid hormones act via specific receptors, and these play an important physiological role in the ovary. The objective of this study was to evaluate the cellular distribution of progesterone receptors and their staining intensity in different equine luteal structures during the breeding season, as well as their relationship to luteal cell composition, cell proliferation pattern and plasma progesterone (P4) concentration. There was an increase in proliferating cell nuclear antigen (PCNA) expression in large luteal cells from the corpus hemorrhagicum (CH) to mid-luteal phase, followed by a decrease toward the late luteal stage. In the CH, the number of large luteal cells was lower than in other structures. Only large luteal cells showed positive staining for P4 receptors. An increase in staining intensity for P4 receptors was observed between CH and mid-phase corpus luteum, and CH and late-phase corpus luteum. Synthesis of P4 started at a very early stage of the luteal structure and was accompanied by an increase in P4 receptors and PCNA expression, and proliferation of large luteal cells, until mid-luteal phase. These data suggest that large luteal cells might play an important role in the regulation or synthesis of P4 in equine luteal structures.
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Hapon, María Belén, Alicia B. Motta, Marcelo Ezquer, Melisa Bonafede, and Graciela A. Jahn. "Hypothyroidism prolongs corpus luteum function in the pregnant rat." Reproduction 133, no. 1 (January 2007): 197–205. http://dx.doi.org/10.1530/rep-06-0035.
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It has been shown that hypothyroidism in the rat produces a prolongation of pregnancy associated with a delay in the fall of circulating progesterone (P4) at term. The aim of the present work is to determine whether the delayed P4decline in hypothyroid mother rats is due to a retarded induction of P4degradation to 20αOH P4or to a stimulation of its synthesis, and to investigate the possible mechanisms that may underlie the altered luteal function. We determined by RIA the circulating profile of the hormones (TSH, PRL, LH, P4, PGF2α, and PGE2) involved in luteal regulation at the end of pregnancy and, by semiquantitative RT-PCR, the expression of factors involved in P4synthesis (CytP450scc, StAR, 3βHSD, PRLR) and metabolism (20αHSD, PGF2αR, iNOS and COX2). Our results show that the delay in P4decline and parturition is the resultant of retarded luteal regression, caused by a combination of decreases in luteolytic factors, mainly luteal PGF2α, iNOS mRNA expression and also circulating LH, and increased synthesis or action of luteotrophic factors, such as luteal and circulating PGE2 and circulating PRL. All these changes may be direct causes of the decreased 20αHSD mRNA and protein (measured by western blot analysis) expression, which in the presence of unchanged expression of the factors involved in P4synthesis results in elevated luteal and circulating P4that prolonged pregnancy and also may favor longer survival of the corpus luteum.
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Ziecik, Adam J., Emilia Przygrodzka, Beenu M. Jalali, and Monika M. Kaczmarek. "Regulation of the porcine corpus luteum during pregnancy." Reproduction 156, no. 3 (September 2018): R57—R67. http://dx.doi.org/10.1530/rep-17-0662.
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The new corpora lutea (CLs) in pigs are formed from the preovulatory follicles after the luteinizing hormone (LH) surge. However, total autonomy and independence of CLs from LH up to Day 12 of cycle has recently been questioned. Transformation of estrous cycle CL to CL of pregnancy initiated by embryonic signals requires not only the cessation of prostaglandin F2 (PGF2α) supply to the luteal tissue but also needs the CL to overcome luteolytic acquisition and/or changing its sensitivity to PGF2αduring Days 12–14 of pregnancy. The luteolytic cascade is prevented by inhibition of lymphocyte infiltration and leucocyte recruitment, limitation of cell apoptosis, upregulation of pregnancy-associated genes and an enhanced antiluteolytic role of PGE2. Our ‘two-signal switch hypothesis’ highlights the importance ofpostPGF2αand PGE2receptor signaling pathways activation in CLs during luteolysis and rescue. The ‘luteolytic switch’ involves increased expression of many regression mediators and activation of thepostPTGFR signaling pathway. The ‘rescue switch’ initiated by embryonic signals – estradiol 17β and PGE2– inducespostPTGER2/4 pathway, turning the ‘luteolytic switch’ off and triggering activity of genes responsible for CL maintenance. In mid and late pregnancy, CLs are maintained by LH and the synergistic action of metabolic hormones. This paper provides an outline of recent views on CL regression, rescue and maintenance during pregnancy in pigs that conflict with previous paradigms and highlights new findings regarding the actions of prostaglandins, role of microRNAs (miRNA) and immune system and signaling pathways governing the life cycle of porcine CL.
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Luck, M. R., J. A. Shale, and J. H. Payne. "DIRECT STIMULATION OF BOVINE OVARIAN PROGESTERONE SECRETION BY LOW CONCENTRATIONS OF a-INTERFERON." Journal of Endocrinology 135, no. 2 (November 1992): R5—R8. http://dx.doi.org/10.1677/joe.0.135r005.
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ABSTRACT The ruminant conceptus secretes proteins during early pregnancy which maintain the corpus luteum. These trophoblast proteins are related to the αII-interferons and prevent luteolysis indirectly by disrupting the secretion of endometrial prostaglandin. Although trophoblast interferons appear to be largely confined to the uterine lumen, it remains possible that they also act peripherally. This report describes in vitro studies which suggest that interferon may influence hormone secretion by the ovary directly. The study employed i) a well defined serum-free culture model in which bovine granulosa cells secrete the luteal hormones progesterone and oxytocin, and ii) serum-free and serum-supplemented cultures of cells from early CL. Dose-response experiments were performed using bovine recombinant α-interferon (brIFN). Progesterone and oxytocin secretions were measured over 4-5 days of culture and DNA content was also determined. Low concentrations of brIFN (10−15 mol/l to 10−11 mol/l) stimulated progesterone secretion by granulosa cells by up to three fold, without significantly affecting oxytocin concentrations or culture DNA content. Concentrations of 10−10 mol/l to 10−7 mol/l suppressed progesterone secretion in a log dose-related manner (r=0.97) with evidence of toxicity (lower oxytocin concentrations and significantly reduced DNA compared with controls). Progesterone secretion by luteal cells in serum-free culture was stimulated in the presence of 10−15 mol/l brIFN, whilst high concentrations again caused inhibition. The data show that ovarian cells can respond directly to low concentrations of interferon-like proteins. They also demonstrate an inhibition by high doses which may mask the stimulatory effect in this model. The data suggest that the early corpus luteum may be directly influenced by α-interferon. A stimulation of progesterone, but not of oxytocin, secretion from ovarian cells would be consistent with a role for conceptus proteins in maintaining the corpus luteum of pregnancy.
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Bramley, T. A., G. S. Menzies, A. S. McNeilly, and H. G. Friesen. "Receptors for lactogenic hormones in the ovine corpus luteum. II: Specific inactivation of ovine prolactin." Journal of Endocrinology 113, no. 3 (June 1987): 375–81. http://dx.doi.org/10.1677/joe.0.1130375.
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ABSTRACT Sheep corpus luteum homogenates and membrane fractions discriminate between 125I-labelled human GH (hGH) and ovine prolactin (oPRL). The present studies were designed to establish whether ovine luteal tissue possessed a prolactin-specific inactivating enzyme. Preincubation of sheep luteal microsomes and cytosol fractions with 125I-labelled hGH had little effect on the ability of the hormone to rebind to pig luteal lactogenic receptors. In contrast, sheep luteal tissue fractions markedly decreased the binding ability of 125I-labelled oPRL. However, despite the profound loss of receptor-binding activity, there was no change in protein-bound radioactivity, nor in the elution profile of 125I-labelled oPRL by gel chromatography on Sephadex G-100. Moreover, the disparity between 125I-labelled hGH and oPRL was not overcome by preincubation of sheep luteal membranes with protease inhibitors of differing specificities. We conclude that the disparity between the binding of hGH and oPRL in ovine tissues was due to the selective inactivation of oPRL. However, the activity responsible did not degrade the hormone extensively, nor was its action blocked by a range of protease inhibitors. J. Endocr. (1987) 113, 375–381
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Rekawiecki, R., and J. Kotwica. "Molecular regulation of progesterone synthesis in the bovine corpus luteum." Veterinární Medicína 52, No. 9 (January 7, 2008): 405–12. http://dx.doi.org/10.17221/1996-vetmed.
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In bovine luteal cells, progesterone can directly affect its own synthesis by increasing the activity of 3β-HSD. The effect of progesterone on its own secretion coincides with increased expression of the genes for 3β-HSD, StAR, and cytochrome P450scc. Therefore, progesterone regulates its own synthesis by affecting the activity of the enzymes that take part in luteal steroidogenesis, and also by affecting the expression of the genes for these enzymes. The aims of this study were: (a) to determine whether progesterone affects the expression of the gene for its own receptor, thereby affecting its own synthesis; and (b) to determine whether oxytocin and noradrenaline affect the expression of the genes for the oxytocin receptor (OT-R), the progesterone receptor (P4-R), and the β<sub>2</sub> receptor (β<sub>2</sub>-R), thereby regulating luteal steroidogenesis. Two populations of luteal cells were used in the present study: from 6<sup>th</sup>–10<sup>th</sup> and 11<sup>th</sup>–16<sup>th</sup> days of the estrous cycle, which were isolated from <i>corpus luteum</i> (CL) from slaughtered cows. The luteal cells were treated for six hours with one of the following hormones: luteinizing hormone (LH; 100 ng/ml); progesterone (P<sub>4</sub>; 10<sup>–5</sup>M); progesterone antagonist (aP<sub>4</sub>; 10<sup>–5</sup>M); noradrenaline (NA; 10<sup>–5M</sup>); or actinomycin D (ActD; 500 ng/ml). After treatment, the medium was collected for the determination of progesterone concentration. With LH, the P<sub>4</sub> concentration in the medium increased with both 6<sup>th</sup>–10<sup><sup>th</sup> and 11<sup>th</sup>–16<sup>th</sup> days. None of the other treatments affected the progesterone concentration of the medium. The level of expression of the genes for OT-R, P<sub>4</sub>-R and β<sub>2</sub>-R were determined. Total RNA was extracted from cells, treated with DNase, and subjected to reverse transcription. Treatment with luteinizing hormone was the only treatment that increased the level of expression of the gene for P<sub>4</sub>-R in both 6<sup>th</sup>–10<sup>th</sup> and 11<sup>th</sup>–16<sup>th</sup> days of the estrous cycle. Both treatment with luteinizing hormone and treatment with progesterone increased the level of expression of the gene for OT-R in 6<sup>th</sup>–10<sup>th</sup> days. The basal level of expression of the gene for OT-R was higher in 6<sup>th</sup>–10<sup>th</sup> days than in 11<sup>th</sup>–16<sup>th</sup> days. This suggests that there is positive feedback between progesterone and oxytocin, with both playing a role as a local, intra-ovarian factor that enhances the function of the <i>corpus luteum</i>.
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Azuma, C., F. Saji, T. Kimura, Y. Tokugawa, M. Takemura, Y. Samejima, and O. Tanizawa. "Steroid hormones induce macrophage colony-stimulating factor (MCSF) and MCSF receptor mRNAs in the human endometrium." Journal of Molecular Endocrinology 5, no. 2 (October 1990): 103–8. http://dx.doi.org/10.1677/jme.0.0050103.
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ABSTRACT We investigated the biological effects of sex-steroid hormones, secreted from the corpus luteum and placenta, on the induction of mRNAs encoding macrophage colony-stimulating factor (MCSF) and c-fms proto-oncogene (MCSF receptor) in human endometrium. RNA was extracted from the placenta and endometrium of both pregnant and non-pregnant women, and Northern blot analysis was performed on poly(A)+ RNA using MCSF or c-fms proto-oncogene cDNA as the probe. Results showed: (1) that MCSF mRNA was expressed in the placenta and endometrium of the pregnant uterus, (2) that c-fms proto-oncogene mRNA was also expressed in the placenta and endometrium of the pregnant uterus, and (3) that exogenous sex-steroid hormones could induce the expression of MCSF and c-fms proto-oncogene mRNAs in the endometrium of non-pregnant women. These results indicate that sex-steroid hormones secreted by the corpus luteum and/or placenta influence endometrial and placental growth and differentiation via a mechanism of action involving local production of MCSF and its receptor.
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Fraser, H. M., M. Abbott, N. C. Laird, A. S. McNeilly, J. J. Nestor, and B. H. Vickery. "Effects of an LH-releasing hormone antagonist on the secretion of LH, FSH, prolactin and ovarian steroids at different stages of the luteal phase in the stumptailed macaque (Macaca arctoides)." Journal of Endocrinology 111, no. 1 (October 1986): 83–90. http://dx.doi.org/10.1677/joe.0.1110083.
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ABSTRACT The role of the pituitary gonadotrophins in controlling luteal function in the stumptailed macaque has been investigated by examining profiles of serum concentrations of LH, FSH, progesterone and oestradiol in daily blood samples from 13 monkeys during the menstrual cycle, and in blood samples taken at hourly intervals between 09.00 and 21.00 h on different days of the luteal phase in 13 cycles. The effects of acute withdrawal of gonadotrophins was investigated by administering a single injection of 300 μg LHRH antagonist/kg body weight at different stages of the luteal phase during 28 cycles. Although there were high basal values and marked fluctuations of bioactive LH during the first 4 days after the LH peak, progesterone profiles showed no corresponding short-term changes, there being a slow and steady rise in progesterone concentrations during the sampling periods. After day 5, basal LH secretion decreased, but high amplitude LH pulses were identified which were associated with episodes of progesterone secretion. Administration of the LHRH antagonist caused a suppression of bioactive LH and progesterone concentrations at all stages of the luteal phase, although some basal secretion of progesterone was maintained through the 24-h period of effective antagonist gonadotroph blockade. Luteal function recovered apparently normally in all monkeys treated in the early–mid-luteal phase. Serum concentrations of FSH and oestradiol fluctuated comparatively less during the 12-h sampling periods, and the antagonist had less suppressive effects on the concentrations of these hormones. The LHRH antagonist had no apparent effect on prolactin release. It appears that the corpus luteum is relatively unresponsive to the high serum LH concentrations during the early luteal phase, but that responsiveness increases as the corpus luteum develops. The corpus luteum is, however, susceptible to withdrawal of LH not only in the mid–late luteal phase when the relationship with LH is apparent, but also during the early luteal phase. J. Endocr. (1986) 111, 83–90
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Shukla, Akshara, Rohitash Jamwal, and Kumud Bala. "ADVERSE EFFECT OF COMBINED ORAL CONTRACEPTIVE PILLS." Asian Journal of Pharmaceutical and Clinical Research 10, no. 1 (January 1, 2016): 17. http://dx.doi.org/10.22159/ajpcr.2017.v10i1.14565.
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ABSTRACTOral contraceptive (OC) pills contain estrogen and progestin that are synthetic analogs of natural hormones. These synthetic hormones affectthe hypothalamus-pituitary-gonadal axis of the female reproductive system. There are many types of contraceptives; most of the OC pills preventpregnancy by inhibiting ovulation. Estrogen and progestin are two female reproductive hormones that are critical. Typically, estradiol is producedby growing follicle (ovaries) which stimulates the hypothalamus to produce the gonadotropin-releasing hormone, which further stimulates theanterior pituitary to produce follicle-stimulating hormone (FSH) and luteinizing hormone (LH). LH production triggers the ovulation. Similarly, theprogesterone is produced by corpus luteum (ovaries), which triggers the production of FSH and LH. There are many types of progesterone available.Long-term usage of synthetic estrogen and progesterone can disturb the balance between the level of these hormones in the body. This imbalance maylead to severe side effects such as breast cancer, cervical cancer, thrombosis, direct impact on the brain, and infertility.Keywords: Estrogen, Progesterone, Contraceptives, Herbal contraceptives.
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Papa, PC, and B. Hoffmann. "The Corpus Luteum of the Dog: Source and Target of Steroid Hormones?" Reproduction in Domestic Animals 46, no. 4 (February 21, 2011): 750–56. http://dx.doi.org/10.1111/j.1439-0531.2010.01749.x.
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Romero, Jared J., Alfredo Q. Antoniazzi, Natalia P. Smirnova, Brett T. Webb, Fang Yu, John S. Davis, and Thomas R. Hansen. "Pregnancy-associated genes contribute to antiluteolytic mechanisms in ovine corpus luteum." Physiological Genomics 45, no. 22 (November 15, 2013): 1095–108. http://dx.doi.org/10.1152/physiolgenomics.00082.2013.
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The hypothesis that ovine luteal gene expression differs due to pregnancy status and day of estrous cycle was tested. RNA was isolated from corpora lutea (CL) on days 12 and 14 of the estrous cycle (NP) or pregnancy (P) and analyzed with the Affymetrix bovine microarray. RNA also was isolated from luteal cells on day 10 of estrous cycle that were cultured for 24 h with luteolytic hormones (OXT and PGF) and secretory products of the conceptus (IFNT and PGE2). Differential gene expression (>1.5-fold, P < 0.05) was confirmed using semiquantitative real-time PCR. Serum progesterone concentrations decreased from day 12 to day 15 in NP ewes ( P < 0.05) reflecting luteolysis and remained >1.7 ng/ml in P ewes reflecting rescue of the CL. Early luteolysis ( days 12–14) was associated with differential expression of 683 genes in the CL, including upregulation of SERPINE1 and THBS1. Pregnancy on day 12 (55 genes) and 14 (734 genes) also was associated with differential expression of genes in the CL, many of which were ISGs (i.e., ISG15, MX1) that were induced when culturing luteal cells with IFNT, but not PGE2. Finally, many genes, such as PTX3, IL6, VEGF, and LHR, were stabilized during pregnancy and downregulated during the estrous cycle and in response to culture of luteal cells with luteolytic hormones. In conclusion, pregnancy circumvents luteolytic pathways and activates or stabilizes genes associated with interferon, chemokine, cell adhesion, cytoskeletal, and angiogenic pathways in the CL.
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Dahham, Haddawi M. "Treatment of anoestrus local Iraqi buffaloes (Bubalus bubalis) using different hormones - field study." Iraqi Journal of Veterinary Medicine 38, no. 1 (June 1, 2014): 121–23. http://dx.doi.org/10.30539/iraqijvm.v38i1.264.
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This study aimed to evaluate the efficacy of different hormonal treatments protocols (PGF2α ,GnRH, estradiol and progesterone) hormones on reproductive performance of postpartum anoestrus native dairy River buffaloes (Bubalus bubalis), endemic south of Baghdad under field conditions . Present study was conducted on 128 animals that had postpartum anoestrus (PPA) for a period between 4 to 8 months. The animals were subjected to two experiments according to the type of anoestrus. In the first experiment 94 animals (73.5%) with persistent corpus luteum on their ovaries without any signs of estrous (sub-oestrus) were classified into two sub-groups.Sub-group1 (n=47) treated with PGF2α hormone alone and sub-group 2 (n= 47) were treated by two injections. The first injection was PGF2α. while the second injection GnRH+ PGF2α was injected after 9 days.In second experiment 34 buffalo cows without any structure on their ovaries (True anestrous) were classified into two sub-groups according to design of the treatment. Sub-group 1(n=14) was treated with estradiol as single injection. Sub-Group 2(n=20) received estradiol + progesterone .The results indicated that the pregnancy rate in sub- groups1 and 2 of the first experiment were 85.1% and 89% respectively , which was not significantly differ from each other (P < 0.05). While in the second experiment, the pregnancy rate for the first and second sub- groups were 71% and 75%, respectively. This study concluded that the prevailing situation of anestrous in postpartum buffaloes endemic south of Baghdad is anestrous with corpus luteum (Sub-oestrus) , 94 out of 128 (73.5%) , and the most efficient treatment protocol of these case are PGF2α + GnRH hormones ( pregnancy rate= 89%) . While estradiol + progesterone treatment are efficient in the treatment of animals suffering from true anestrous (pregnancy rate 75%).
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Galvão, António, Angela Tramontano, Maria Rosa Rebordão, Ana Amaral, Pedro Pinto Bravo, Anna Szóstek, Dariusz Skarzynski, Antonio Mollo, and Graça Ferreira-Dias. "Opposing Roles of Leptin and Ghrelin in the Equine Corpus Luteum Regulation: AnIn VitroStudy." Mediators of Inflammation 2014 (2014): 1–13. http://dx.doi.org/10.1155/2014/682193.
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Metabolic hormones have been associated with reproductive function modulation. Thus, the aim of this study was: (i) to characterize the immunolocalization, mRNA and protein levels of leptin (LEP), Ghrelin (GHR) and respective receptors LEPR and Ghr-R1A, throughout luteal phase; and (ii) to evaluate the role of LEP and GHR on progesterone (P4), prostaglandin (PG) E2and PGF2α, nitric oxide (nitrite), tumor necrosis factor-α(TNF); macrophage migration inhibitory factor (MIF) secretion, and on angiogenic activity (BAEC proliferation), in equine corpus luteum (CL) from early and mid-luteal stages. LEPR expression was decreased in late CL, while GHR/Ghr-R1A system was increased in the same stage. Regarding secretory activity, GHR decreased P4in early CL, but increased PGF2α, nitrite and TNF in mid CL. Conversely, LEP increased P4, PGE2, angiogenic activity, MIF, TNF and nitrite during early CL, in a dose-dependent manner. Thein vitroeffect of LEP on secretory activity was reverted by GHR, when both factors acted together. The present results evidence the presence of LEP and GHR systems in the equine CL. Moreover, we suggest that LEP and GHR play opposing roles in equine CL regulation, with LEP supporting luteal establishment and GHR promoting luteal regression. Finally, a dose-dependent luteotrophic effect of LEP was demonstrated.
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Pereira, María M., Monica Mainigi, and Jerome F. Strauss. "Secretory products of the corpus luteum and preeclampsia." Human Reproduction Update 27, no. 4 (March 22, 2021): 651–72. http://dx.doi.org/10.1093/humupd/dmab003.
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Abstract BACKGROUND Despite significant advances in our understanding of the pathophysiology of preeclampsia (PE), there are still many unknowns and controversies in the field. Women undergoing frozen-thawed embryo transfer (FET) to a hormonally prepared endometrium have been found to have an unexpected increased risk of PE compared to women who receive embryos in a natural FET cycle. The differences in risk have been hypothesized to be related to the absence or presence of a functioning corpus luteum (CL). OBJECTIVE AND RATIONALE To evaluate the literature on secretory products of the CL that could be essential for a healthy pregnancy and could reduce the risk of PE in the setting of FET. SEARCH METHODS For this review, pertinent studies were searched in PubMed/Medline (updated June 2020) using common keywords applied in the field of assisted reproductive technologies, CL physiology and preeclampsia. We also screened the complete list of references in recent publications in English (both animal and human studies) on the topics investigated. Given the design of this work as a narrative review, no formal criteria for study selection or appraisal were utilized. OUTCOMES The CL is a major source of multiple factors regulating reproduction. Progesterone, estradiol, relaxin and vasoactive and angiogenic substances produced by the CL have important roles in regulating its functional lifespan and are also secreted into the circulation to act remotely during early stages of pregnancy. Beyond the known actions of progesterone and estradiol on the uterus in early pregnancy, their metabolites have angiogenic properties that may optimize implantation and placentation. Serum levels of relaxin are almost undetectable in pregnant women without a CL, which precludes some maternal cardiovascular and renal adaptations to early pregnancy. We suggest that an imbalance in steroid hormones and their metabolites and polypeptides influencing early physiologic processes such as decidualization, implantation, angiogenesis and maternal haemodynamics could contribute to the increased PE risk among women undergoing programmed FET cycles. WIDER IMPLICATIONS A better understanding of the critical roles of the secretory products of the CL during early pregnancy holds the promise of improving the efficacy and safety of ART based on programmed FET cycles.
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Goyeneche, Alicia A., Jacquelyn M. Harmon, and Carlos M. Telleria. "Cell death induced by serum deprivation in luteal cells involves the intrinsic pathway of apoptosis." Reproduction 131, no. 1 (January 2006): 103–11. http://dx.doi.org/10.1530/rep.1.00751.
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The corpus luteum is a transient endocrine gland specializing in the production of progesterone. The regression of the corpus luteum involves an abrupt decline in its capacity for producing progesterone followed by its structural involution, which is associated with apoptosis of the luteal cells. An in vitro experimental approach is needed to study the molecular mechanisms underlying hormonal regulation of luteal cell death under defined experimental conditions. In this study, we investigated simian virus-40-transformed luteal cells to determine whether they can be driven to apoptosis and, if so, to define the intracellular pathway involved. Luteal cells were cultured in the presence or absence of fetal bovine serum for 24 or 48 h. Under serum starvation conditions, the luteal cells underwent growth arrest accompanied by cell death as evaluated by dye exclusion, and confirmed by two-color fluorescence cell viability/cytotoxicity assay. We next studied whether serum starvation-induced death of luteal cells occurred by apoptosis. Morphologic features of apoptosis were observed in cells stained with hematoxylin after being subjected to serum starvation for 48 h. The apoptotic nature was further confirmed by in situ 3′-end labeling and fragmentation of genomic DNA. Apoptosis of serum-deprived luteal cells was dependent upon caspase activation. Serum starvation induced cleavage of poly (ADP-ribose) polymerase (PARP), suggesting that caspase-3 had been activated under the stress of withdrawal of growth factors. This was confirmed by cleavage of full-length procaspase-3. Finally, the fact that serum starvation promoted the cleavage of full-length procaspase-9 and the decrease in the expression of endogenous Bid, a BH-3-only proapoptotic protein of the Bcl-2 family, indicates that the intrinsic (i.e., mitochondrial) pathway of apoptosis was activated. In summary, we have characterized an in vitro experimental model of luteal cell death that can be utilized to evaluate the role of hormones in apoptosis of luteal cells under defined culture conditions, and to study the mechanism of luteal regression.
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Nishimura, Ryo, and Kiyoshi Okuda. "Multiple roles of hypoxia in ovarian function: roles of hypoxia-inducible factor-related and -unrelated signals during the luteal phase." Reproduction, Fertility and Development 28, no. 10 (2016): 1479. http://dx.doi.org/10.1071/rd15010.
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There is increasing interest in the role of oxygen conditions in the microenvironment of organs because of the discovery of a hypoxia-specific transcription factor, namely hypoxia-inducible factor (HIF) 1. Ovarian function has several phases that change day by day, including ovulation, follicular growth and corpus luteum formation and regression. These phases are regulated by many factors, including pituitary hormones and local hormones, such as steroids, peptides and cytokines, as well as oxygen conditions. Hypoxia strongly induces angiogenesis because transcription of the potent angiogenic factor vascular endothelial growth factor (VEGF) is regulated by HIF1. Follicular development and luteal formation are accompanied by a marked increase in angiogenesis assisted by HIF1–VEGF signalling. Hypoxia is also one of the factors that induces luteolysis by suppressing progesterone synthesis and by promoting apoptosis of luteal cells. The present review focuses on recent studies of hypoxic conditions, as well as HIF1-regulated genes and proteins, in the regulation of ovarian function.
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Bramley, T. A., and G. S. Menzies. "Specificity studies of particulate binding sites for steroid hormones in subcellular fractions of the porcine corpus luteum." Journal of Endocrinology 136, no. 3 (March 1993): 371–80. http://dx.doi.org/10.1677/joe.0.1360371.
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ABSTRACT We have studied the binding of a number of radiolabelled steroids and lipophilic substances to porcine corpus luteum (CL) particulate fractions. Following preincubation of CL homogenates with radiolabelled progesterone or pregnenolone prior to fractionation on continuous sucrose density gradients, a broad peak of binding was observed associated with a particulate fraction of buoyant density 1·05–1·10 g/cm3. Progesterone content also peaked at a similar buoyant density (1·06–1·12 g/cm3). Pretreatment of luteal homogenates with digitonin perturbed the buoyant density of the progesterone-binding particulate fraction to 1·10–1·14 g/cm3 and sharpened the binding peak. Progesterone content was also perturbed to a similar extent by digitonin pretreatment, without release of the steroid. Oestrogens were also sequestered by this fraction, but steroid precursors (cholesterol, cholesterol ester), corticosteroids (cortisol, corticosterone), sterol conjugates (oestrone sulphate, pregnanediol glucuronide) and other lipophilic substances (arachidonic acid, phospholipid, prostaglandins E1, E2 and F2α) were not bound. Androgens were bound weakly by fractions from control gradients but, in the presence of digitonin, significant binding could be demonstrated. Radiolabelled steroids were shown to interact directly with luteal membrane fractions, rather than interacting first with cytosolic steroid receptors which then bound to membranes. Furthermore, [3H]progesterone was not bound by porcine granulosa cell particulate fractions. These observations suggest that this fraction may be involved in sequestration or packaging of progesterone for secretion by the luteal cell. Journal of Endocrinology (1993) 136, 371–380
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WEBLEY, G. E., J. P. HEARN, and M. R. LUCK. "Local progesterone secretion by the marmoset corpus luteum after perfusion with regulating hormones." Acta Endocrinologica 116, no. 3_Suppl (August 1987): S111—S112. http://dx.doi.org/10.1530/acta.0.114s111a.
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Laherty, Richard F., Daniel Rotten, May Yamamoto, and Robert B. Jaffe. "Effects of oestradiol and prolactin on progesterone production by rhesus monkey luteal cells in vitro." Acta Endocrinologica 108, no. 2 (February 1985): 266–72. http://dx.doi.org/10.1530/acta.0.1080266.
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Abstract. The effects of oestradiol and prolactin (Prl) on progesterone production by dispersed monkey luteal cells were examined. Corpora lutea were recovered from monkeys 5–7 days following ovulation induction during the puerperium. The tissue was dispersed by collagenase and mechanical disruption. The resulting cells were incubated in Dulbecco's modified Eagle's medium, containing the hormones to be tested, for 3 h at 37°C. The medium was removed and assayed for progesterone by RIA. Human luteinizing hormone (hLH) produced a significant, dose-related increase in progesterone secretion that was comparable to that produced by dibutyryl cyclic adenosine monophosphate. Human follicle stimulating hormone (hFSH) had no effect upon progesterone production by the luteal cells. Oestradiol (100–10 000 pg/ml) produced a significant, dose-related decrease in both basal and hLH-stimulated progesterone production. Ovine Prl (oPrl) had neither a stimulatory nor an inhibitory effect upon basal progesterone secretion at doses up to 1000 ng/ml. Further, oPrl did not affect hLH-stimulated progesterone production. We conclude that oestradiol is a potent inhibitor of luteal progesterone secretion in vitro and that Prl does not inhibit progesterone production in the primate corpus luteum under these experimental conditions.
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Bryant-Greenwood, GD. "Human decidual and placental relaxins." Reproduction, Fertility and Development 3, no. 4 (1991): 385. http://dx.doi.org/10.1071/rd9910385.
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The human placenta and decidua are intrauterine production sites for a range of polypeptide hormones. Relaxin is one of these hormones, its production having been demonstrated by immunocytochemistry and Northern analysis. There are two relaxin genes in the human genome, termed H1 and H2; only the latter is expressed in cyclic and pregnant corpus luteum. However, it has recently been shown that both genes are expressed in the decidua and placenta. It is not known whether both are translated. These hormone(s) may act in a paracrine fashion and be partly responsible for the control of enzymes and inhibitors involved in collagen remodelling in the fetal membranes in the last weeks of pregnancy. An autocrine role of decidual relaxin and a possible decidual-cell/macrophage/extracellular-matrix interaction is described; this may act as a unit in the elaboration of a range of hormones.
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Bachelot, Anne, Julie Beaufaron, Nathalie Servel, Cécile Kedzia, Philippe Monget, Paul A. Kelly, Geula Gibori, and Nadine Binart. "Prolactin independent rescue of mouse corpus luteum life span: identification of prolactin and luteinizing hormone target genes." American Journal of Physiology-Endocrinology and Metabolism 297, no. 3 (September 2009): E676—E684. http://dx.doi.org/10.1152/ajpendo.91020.2008.
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The corpus luteum (CL) plays a central role in the maintenance of pregnancy in rodents, mainly by secreting progesterone. Female mice lacking prolactin (PRL) receptor (R) are sterile due to a failure of embryo implantation, which is a consequence of decreased luteinizing hormone (LH) receptor expression in the CL and inadequate levels of progesterone. We attempted to treat PRLR−/− females with human chorionic gonadotropin (hCG) and showed a de novo expression of LHR mRNA in the corpora lutea. Binding analysis confirmed that the LHR in hCG-treated PRLR−/− animals was functional. This was accompanied with increased expression of steroidogenic enzymes involved in progesterone synthesis. Despite these effects, no embryo implantation was observed because of high expression of 20α-hydroxysteroid dehydrogenase. To better appreciate the molecular mechanisms underlying maintenance of the CL, a series of mRNA expression-profiling experiments was performed on isolated corpora lutea of PRLR−/− and hCG-treated PRLR−/− mice. This approach revealed several novel candidate genes with potentially pivotal roles in ovarian function, among them, p27, VE-cadherin, Pten, and sFRP-4, a member of the Wnt/frizzled family. This study showed the differential role of PRL and LH in CL function and identified new targets of these hormones in luteal cells.
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Bramley, T. A., G. S. Menzies, A. S. McNeilly, and H. G. Friesen. "Receptors for lactogenic hormones in the ovine corpus luteum. III: Inhibition of 125I-labelled human growth hormone binding by a high molecular weight factor in ovine corpus luteum cytosol." Journal of Endocrinology 114, no. 3 (September 1987): 383–89. http://dx.doi.org/10.1677/joe.0.1140383.
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ABSTRACT Ovine luteal cytosol fractions inhibited the specific binding of 125I-labelled human GH and ovine prolactin (oPRL) to ovine luteal microsomes in a dose-dependent fashion. Inhibition was dependent on divalent cation concentrations, and was abolished by divalent metal ion chelating agents or by boiling. Inhibition was not due to ionic strength or salt effects on hormone binding, the release of endogenously bound oPRL into the cytosol fraction during tissue disruption and fractionation, or the presence of a soluble (or solubilized) lactogenic receptor in ovine cytosol preparations. Gel chromatography of cytosol fractions gave a molecular weight for the inhibitor of approximately 50 000. J. Endocr. (1987) 114, 383–389
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Khan-Dawood, FS, J. Yang, and MY Dawood. "Hormonal regulation of connexin-43 in baboon corpora lutea." Journal of Endocrinology 157, no. 3 (June 1, 1998): 405–14. http://dx.doi.org/10.1677/joe.0.1570405.
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The synthesis and secretion of progesterone in the corpus luteum are regulated by both endocrine and paracrine/ autocrine factors which affect the steroidogenic cells. Evidence suggests that these cells communicate via cell-cell junctional proteins, the connexins. Previously we have shown that connexin-43 is expressed in both human and baboon (Papio hamadryus anubis) corpora lutea, with differential expression throughout luteal development, but is not detectable in corpora albicantia. We have examined the effect of human chorionic gonadotropin (hCG), oxytocin, clomiphene citrate and the anti-progesterone onapristone on expression of connexin-43 protein in the early luteal phase 1-5 days after the mid-cycle luteinizing hormone (LH) surge (LH+ 1-5 days), the mid-luteal phase 6-10 days after the LH surge (LH+ 6-10 days), and the late luteal phase 11-15 days after the LH surge (LH+ 11-15 days) in corpora lutea obtained from normal adult cycling females. Connexin-43 was localized by immunohistochemistry in cultured cells from all the three stages. Western blot analysis of the treated cells indicated the presence of two bands at 43 and 45 kDa. The band at 45 kDa was found to be phosphorylated connexin-43, indicating the presence of functional gap junctions. hCG (10 IU/ml) stimulated the expression of connexin-43 throughout luteal development; however, maximum expression occurred in the early luteal phase with a significantly greater expression of the non-phosphorylated protein. In contrast, in the mid-luteal phase, the expression of the phosphorylated protein was predominant. Oxytocin (200 mU/ml) also stimulated connexin-43 expression throughout luteal development with similar effects on the phosphorylated and non-phosphorylated protein in the early and mid-luteal phase; however, compared with hCG, oxytocin had a greater effect on mid-luteal phase connexin-43 expression. In the presence of both hCG and oxytocin, the expression of connexin-43 was significantly higher than the control only in the late luteal phase. Both clomiphene citrate and onapristone suppressed connexin-43 expression, and concomitant addition of hCG did not counteract their effect. In the context of our previous studies, it is concluded that, together with LH/hCG and the steroid hormones, oxytocin is involved in cell-cell contact-dependent communication in the corpus luteum.
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Pamungkas, Fitra Aji, Ria Sari Gail Sianturi, Elizabeth Wina, and Diana Andrianita Kusumaningrum. "Chitosan nanoparticle of hCG (Human Chorionic Gonadotrophin) hormone in increasing induction of dairy cattle ovulation." Jurnal Ilmu Ternak dan Veteriner 21, no. 1 (March 31, 2016): 34. http://dx.doi.org/10.14334/jitv.v21i1.1343.
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<p class="abstrak2">A controlled release delivery system of human chorionic gonadotropin (hCG) hormone helps to overcome the rapid degradation of hCG hormone in the blood, to avoid the use of multiple injections for ovulation induction and to enhance reproductive efficacy. This study aimed to prepare chitosan nanoparticles hCG (CS-NPh) and to determine its efficacy as nasal spray of CS-NPh. The observed parameters include physico-chemical characteristics of CS-NPh and the follicle size, corpus luteum, the time of ovulation and onset of estrus performed after administration of CS-NPh as a nasal spray compared with intramuscular hCG (control) at a dose of 1,000 IU in dairy cattle. The result showed that the formation of the hormone hCG nanoparticles is still in the size range of nanoparticles with a well and more stable molecular mass distribution, so it can be used as a carrier component of hormones. The result showed that the time of ovulation after hCG by intramuscular (day to 3.13±0.35) and CS-NPh as a nasal spray (days to 3.33±0.49) with the follicle size by 1.62±0.22 and 1.76±0.28 cm showed no significant differences (p> 0.05), likewise the size of the corpus luteum and onset of oestrus. This indicates that administration of CS-NPh as a nasal spray can be used in enhancing the induction of ovulation in dairy cattles.</p><strong>Key Words: </strong>Nanoparticles, hCG, Nasal Spray, Ovulation
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Przygrodzka, E., M. M. Kaczmarek, P. Kaczynski, and A. J. Ziecik. "Steroid hormones, prostanoids, and angiogenic systems during rescue of the corpus luteum in pigs." REPRODUCTION 151, no. 2 (February 2016): 135–47. http://dx.doi.org/10.1530/rep-15-0332.
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In order to characterize the transition of the corpora lutea (CL) from acquisition of luteolytic sensitivity to rescue of luteal function: i) the expression of 38 factors associated with steroids, prostanoids, and angiogenic systems and ii) concentrations of the main hormones responsible for maintenance of CL function in cyclic and pregnant pigs were examined. Additionally, the effect of prostaglandin (PG) E2 and F2α on luteal function during the estrous cycle and pregnancy was evaluated in vitro. Significantly up-regulated gene expression was revealed in CL collected on day 14 of the estrous cycle (CYP19A1, ESR2, PTGS2, HIF1A, and EDN1) and on days 12–14 of pregnancy (SCARB1, PGRMC1, STAR, HSD3B1, NR5A1, PTGFR, PTGER4, and VEGFA). Elevated concentrations of estradiol-17β and PGE2 occurred in CL on days 12 and 14 of pregnancy respectively, while an increased intraluteal PGF2α content was noted on day 14 of the estrous cycle. Both PGs increased the synthesis of progesterone by cultured luteal slices obtained on day 14 of pregnancy, in contrast to the action of PGF2α on the corresponding day of the estrous cycle. PGE2 stimulated cAMP production via PTGER2 and PTGER4, while PGF2α elevated the content of CREB in cultured luteal slices from CL of pregnant pigs. In silico analysis showed that infiltration of lymphocytes and apoptosis of microvascular endothelium were activated in CL on day 12 of the estrous cycle vs pregnancy. Summarizing, an abundance of E2 and PGE2 during pregnancy regulates specific pathways responsible for steroidogenesis, the prostanoid signaling system and angiogenesis during rescue from luteolysis in porcine CL.
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Wojtysiak, Dorota, Ewa Kapkowska, Piotr Pasciak, and Branislav Zivkovic. "Steroid hormones concentration in the postovulatory follicles of the goose." Biotehnologija u stocarstvu 21, no. 1-2 (2005): 91–97. http://dx.doi.org/10.2298/bah0502091w.
Full textAbstract:
The purpose of the present investigation was to measure the concentrations of progesterone (P4), androgens (A) and estradiol (E2) in follicular wall of the three largest postovulatory follicles. The major findings in the present study are: 1) the postovulatory follicles of the goose, which are not homologous with the mammalian corpus luteum, are an active endocrine tissue. 2) Follicular wall of postovulatory follicles can synthesize large amounts of progesterone and lesser amounts of androgens and estradiol. This study also suggest that the steroidogenic potential of the follicular cells was markedly reduced during the process of follicular regression.
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Tasende, C., M. Rodríguez-Piñón, S. Acuña, E. G. Garófalo, and M. Forsberg. "Corpus luteum life span and pituitary oestrogen and progesterone receptors in cyclic and gonadotrophin-releasing hormone-treated anoestrous ewes." Reproduction, Fertility and Development 17, no. 7 (2005): 721. http://dx.doi.org/10.1071/rd05058.
Full textAbstract:
The present study investigated the pituitary oestrogen (ER) and progesterone (PR) receptor concentrations in ewes during the oestrous cycle in the breeding season (n = 19), and in anoestrous ewes treated with gonadotrophin-releasing hormone (GnRH) (n = 11) and anoestrous ewes treated with progesterone + GnRH (n = 11). The pituitary ER and PR concentrations at the expected time of ovulation and in the early and late luteal phases were measured by binding assay. The pattern of pituitary ER and PR concentrations in the progesterone + GnRH-treated ewes resembled the pattern found during the normal oestrous cycle, with ER and PR concentrations decreasing from the time of ovulation to the early luteal phase. In contrast, in ewes treated with GnRH alone, ER and PR concentrations increased in the early luteal phase, which may increase the inhibitory effects of steroid hormones on luteinising hormone secretion, ultimately leading to the development of subnormal luteal phases.
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Wittmaack, F. M., J. A. Holt, and J. R. Schreiber. "Cholesterol metabolism in estrogen-sensitive progestin synthesis by rabbit corpus luteum." American Journal of Physiology-Endocrinology and Metabolism 251, no. 4 (October 1, 1986): E457—E463. http://dx.doi.org/10.1152/ajpendo.1986.251.4.e457.
Full textAbstract:
To learn whether either reduced de novo cholesterol synthesis and/or altered cholesteryl ester metabolism is responsible for the deficient progestin production induced by estrogen withdrawal from pseudopregnant rabbits, we measured the luteal activity of three enzymes: 1) 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase (the rate-limiting step in de novo cholesterol synthesis), 2) cholesteryl ester hydrolase, and 3) acyl coenzyme A:cholesterol acyltransferase (ACAT) in estrogen-stimulated and estrogen-deprived rabbits. The only change in the activity of these enzymes and of the enzyme NADPH-cytochrome c reductase (a microsomal marker enzyme) after estrogen capsule removal for 12 or 24 h was a 30% decrease in HMG-CoA reductase activity after 24 h. The decrease in HMG-CoA reductase activity was not accompanied by a detectable change in either the content or localization of cellular free cholesterol. Previous data from our laboratory have demonstrated that 24 h of estrogen deprivation has no effect on inner mitochondrial membrane P-450 side-chain cleavage activity (a rate-limiting step in the conversion of cholesterol to steroid hormones). These data, and our earlier finding that estrogen deprivation leads to accumulation of cholesteryl ester in the luteal cells, indicate that estrogen maintains rabbit luteal progestin production by stimulating the transfer of cytoplasmic cholesterol to the active site of P-450 side-chain cleavage on the inner mitochondrial membrane.
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Conrad, Kirk P. "Maternal vasodilation in pregnancy: the emerging role of relaxin." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 301, no. 2 (August 2011): R267—R275. http://dx.doi.org/10.1152/ajpregu.00156.2011.
Full textAbstract:
Pregnancy is a unique physiological condition of profound maternal renal and systemic vasodilation. Our goal has been to unveil the reproductive hormones mediating this remarkable vasodilatory state and the underlying molecular mechanisms. In addition to advancing our knowledge of pregnancy physiology, reaching this goal may translate into therapeutics for pregnancy pathologies such as preeclampsia and for diseases associated with vasoconstriction and arterial stiffness in nonpregnant women and men. An emerging player is the 6 kDa corpus luteal hormone relaxin, which circulates during pregnancy. Relaxin administration to rats and humans induces systemic and renal vasodilation regardless of sex, thus mimicking the pregnant condition. Immunoneutralization or elimination of the source of circulating relaxin prevents renal and systemic vasodilation in midterm pregnant rats. Infertile women who become pregnant by donor eggs (IVF with embryo transfer) lack a corpus luteum and circulating relaxin, and they show a markedly subdued gestational increase in glomerular filtration rate. These data implicate relaxin as one of the vasodilatory reproductive hormones of pregnancy. There are different molecular mechanisms underlying the so-called rapid and sustained vasodilatory actions of relaxin. The former is mediated by Gαi/o protein coupling to phosphatidylinositol-3 kinase/Akt (protein kinase B)-dependent phosphorylation and activation of endothelial nitric oxide synthase, the latter by vascular endothelial and placental growth factors, and increases in arterial gelatinase(s) activity. The gelatinases, in turn, hydrolyze big endothelin (ET) at a gly-leu bond to form ET1–32, which activates the endothelial ETB receptor/nitric oxide vasodilatory pathway.
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Bramley, T. A., and G. S. Menzies. "Particulate binding sites for steroid hormones in subcellular fractions of the ovine corpus luteum: properties and hormone specificity." Molecular and Cellular Endocrinology 103, no. 1-2 (July 1994): 39–48. http://dx.doi.org/10.1016/0303-7207(94)90067-1.
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Journal, Baghdad Science. "Studying the Effect of Aqueous Extract from Curcuma Longa on Some Parameters of Cytogenetic, Immunity and Fertility in Female Mice." Baghdad Science Journal 8, no. 1 (March 6, 2011): 73–80. http://dx.doi.org/10.21123/bsj.8.1.73-80.
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The research work was conducted to investigate the effect of oral administration of aqueous extract of turmeric at doses of (5, 10) mg/kg body weight for two weeks daily by determining the genotoxic effect (mitotic index), evaluation of immunological effect (IgG, IgM, IgA, C3, C4) and measuring fertility hormones (follicles stimulation hormone/FSH, lutenising hormone/LH) levels with histological examinations of female albino swiss mice ovaries in comparison with control (normal saline). A clear effect in increasing mitotic activity was reveled for both doses in comparison with control. Results also showed a significant increase in the value of all immunological parameters at both doses, in comparison with control. Also, obvious raise was seen in the levels of FSH and LH hormones for both doses when compared with normal saline treated mice with no significant damage seen in female ovaries tissue, in fact, there were certain changes in mice ovaries tissue which were represented by increasing in the numbers of primary and secondary follicles and in the numbers of corpus luteum at both doses also.
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H., AL-Anbaky K. I. "A study of Serum Steroid Hormones Concentrations Of Pregnant Cows." Iraqi Journal of Veterinary Medicine 33, no. 1 (June 30, 2009): 180–82. http://dx.doi.org/10.30539/iraqijvm.v33i1.731.
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The objective of present work is to estimated peripheral blood serum concentrations of pregnancyhormones, oestradiol , progesterone and testosterone , in cows . For this purpose 24 Frezain- Holsteincows at different stages of pregnancy the blood samples were taken from jugular veins. The serumwere separated and frozen at – 20 c until analysis. The serum hormones were measured by a specificELISA technique (ELISA Linear Multi Reader). The data were represented Mean + S.D. Progesteronewas high during pregnancy reaching a maximum of 91.94 + 26.09 ng/ml during last thirds (6-8months) of pregnancy , but was below 9.12 + 2.41 ng/ml for several months during the pregnancy.Oestradiol levels varied from 9.0+ 2.89 pg/ml in the first thirds of pregnancy to 282.6 + 48 .514 pg/mlduring the last month of gestation. While testosterone hormone level was low 0.32 + 0.12 ng /mlduring pregnancy. The result indicated that the major sources of hormones appeared to be the 0vary(corpus luteum ) and the uterus (placenta). The ovarian contribution was greater during the first – thirdsof pregnancy than later, whereas that made by the placenta was higher during the last thirds ofpregnancy
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Wang, Yizi, Minghui Chen, Jian Xu, Xinyan Liu, Yuwei Duan, Canquan Zhou, and Yanwen Xu. "Core clock gene Bmal1 deprivation impairs steroidogenesis in mice luteinized follicle cells." Reproduction 160, no. 6 (December 2020): 955–67. http://dx.doi.org/10.1530/rep-20-0340.
Full textAbstract:
Luteinization is the event of corpus luteum formation, a way of follicle cells transformation and a process of steroidogenesis alteration. As the core clock gene, Bmal1 was involved in the regulation of ovulation process and luteal function afterwards. Till now, the underlying roles of luteinization played by Bmal1 remain unknown. To explore the unique role of Bmal1 in luteal steroidogenesis and its underlying pathway, we investigated the luteal hormone synthesis profile in Bmal1 knockout female mice. We found that luteal hormone synthesis was notably impaired, and phosphorylation of PI3K/NfκB pathway was significantly activated. Then, the results were verified in in vitro cultured cells, including isolated Bmal1 interference granulosa cells (GCs) and theca cells (TCs), respectively. Hormones levels of supernatant culture media and mRNA expressions of steroidogenesis-associated genes (star, Hsd3β2, cyp19a1 in GCs, Lhcgr, star, Hsd3β2, cyp17a1 in TCs) were mutually decreased, while the phosphorylation of PI3K/NfκB was promoted during in vitro luteinization. After PI3K specific-inhibitor LY294002 intervention, mRNA expressions of Lhcgr and Hsd3β2 were partially rescued in Bmal1 interference TCs, together with significantly increased androstenedione and T synthesis. Further exploration in TCs demonstrated BMAL1 interacted directly but negatively with NfκB p65 (RelA), a subunit which was supposed as a mediator in Bmal1-governed PI3K signaling regulation. Taken together, we verified the novel role of Bmal1 in luteal steroidogenesis, achieving by negative interplay with RelA-mediated PI3K/NfκB pathway.
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Smith, K. B., and H. M. Fraser. "Control of progesterone and inhibin secretion during the luteal phase in the macaque." Journal of Endocrinology 128, no. 1 (January 1991): 107–13. http://dx.doi.org/10.1677/joe.0.1280107.
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ABSTRACT We investigated the temporal relationship between serum concentrations of progesterone and immuno-reactive inhibin after treatment with an LHRH antagonist ([N-Ac-d-Nal(2)1,d-pCl-Phe2,d-Trp3,d-hArg(Et2)6,d-Ala10]-LHRH), during the mid-luteal phase in the macaque. Further, in an attempt to obtain a model of transitory suppression of luteal function, the effect of treatment with the LHRH antagonist for 1, 2 or 3 days during the mid-luteal phase on serum concentrations of progesterone and immunoreactive inhibin was compared. Differences in the pattern of decline of the two hormones were observed. Progesterone concentrations fell by 6 h after antagonist administration while inhibin was not significantly suppressed until 48 h. Treatment with three injections of LHRH antagonist caused a sustained suppression of luteal function as shown by low serum concentrations of progesterone and inhibin. Recovery of progesterone and inhibin secretion was observed in two out of six macaques treated with two injections of antagonist and in three out of six treated with a single injection. Therefore, with the regimens of LHRH antagonist which we employed this approach was not conducive to obtaining a reliable transitory suppression of luteal function. To elucidate further the gonadotrophin control of inhibin, six macaques were treated with three injections of the LHRH antagonist to induce a permanent suppression of luteal function but received concomitantly either human chorionic gonadotrophin (hCG) or human FSH daily for 5 days (n = 3 per group). FSH failed to prevent the antagonist-induced fall in progesterone and inhibin while hCG treatment completely reversed the inhibitory effects of the LHRH antagonist. These results give further support to the concept that the secretion of inhibin, like progesterone, is integrated with the LH control of the corpus luteum. The slower decline in inhibin after LHRH antagonist suggests that the gonadotrophic stimulus to the corpus luteum results in a more prolonged stimulus for inhibin than for progesterone secretion, or that inhibin has a longer metabolic clearance rate. Journal of Endocrinology (1991) 128, 107–113
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McCracken, John A., Edward E. Custer, and Justin C. Lamsa. "Luteolysis: A Neuroendocrine-Mediated Event." Physiological Reviews 79, no. 2 (April 1, 1999): 263–323. http://dx.doi.org/10.1152/physrev.1999.79.2.263.
Full textAbstract:
In many nonprimate mammalian species, cyclical regression of the corpus luteum (luteolysis) is caused by the episodic pulsatile secretion of uterine PGF2α, which acts either locally on the corpus luteum by a countercurrent mechanism or, in some species, via the systemic circulation. Hysterectomy in these nonprimate species causes maintenance of the corpora lutea, whereas in primates, removal of the uterus does not influence the cyclical regression of the corpus luteum. In several nonprimate species, the episodic pattern of uterine PGF2α secretion appears to be controlled indirectly by the ovarian steroid hormones estradiol-17β and progesterone. It is proposed that, toward the end of the luteal phase, loss of progesterone action occurs both centrally in the hypothalamus and in the uterus due to the catalytic reduction (downregulation) of progesterone receptors by progesterone. Loss of progesterone action may permit the return of estrogen action, both centrally in the hypothalamus and peripherally in the uterus. Return of central estrogen action appears to cause the hypothalamic oxytocin pulse generator to alter its frequency and produce a series of intermittent episodes of oxytocin secretion. In the uterus, returning estrogen action concomitantly upregulates endometrial oxytocin receptors. The interaction of neurohypophysial oxytocin with oxytocin receptors in the endometrium evokes the secretion of luteolytic pulses of uterine PGF2α. Thus the uterus can be regarded as a transducer that converts intermittent neural signals from the hypothalamus, in the form of episodic oxytocin secretion, into luteolytic pulses of uterine PGF2α. In ruminants, portions of a finite store of luteal oxytocin are released synchronously by uterine PGF2α pulses. Luteal oxytocin in ruminants may thus serve to amplify neural oxytocin signals that are transduced by the uterus into pulses of PGF2α. Whether such amplification of episodic PGF2α pulses by luteal oxytocin is a necessary requirement for luteolysis in ruminants remains to be determined. Recently, oxytocin has been reported to be produced by the endometrium and myometrium of the sow, mare, and rat. It is possible that uterine production of oxytocin may act as a supplemental source of oxytocin during luteolysis in these species. In primates, oxytocin and its receptor and PGF2α and its receptor have been identified in the corpus luteum and/or ovary. Therefore, it is possible that oxytocin signals of ovarian and/or neural origin may be transduced locally at the ovarian level, thus explaining why luteolysis and ovarian cyclicity can proceed in the absence of the uterus in primates. However, it remains to be established whether the intraovarian process of luteolysis is mediated by arachidonic acid and/or its metabolite PGF2α and whether the central oxytocin pulse generator identified in nonprimate species plays a mediatory role during luteolysis in primates. Regardless of the mechanism, intraovarian luteolysis in primates (progesterone withdrawal) appears to be the primary stimulus for the subsequent production of endometrial prostaglandins associated with menstruation. In contrast, luteolysis in nonprimate species appears to depend on the prior production of endometrial prostaglandins. In primates, uterine prostaglandin production may reflect a vestigial mechanism that has been retained during evolution from an earlier dependence on uterine prostaglandin production for luteolysis.
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Potapov, V. O. "Biological role of nitric oxide donors in pregravid preparation of women with luteal phase deficiency." Infusion & Chemotherapy, no. 3.2 (December 15, 2020): 247–49. http://dx.doi.org/10.32902/2663-0338-2020-3.2-247-249.
Full textAbstract:
Background. At the menstrual cycle beginning there is a proliferation of endometrial cells under the influence of oestrogen, and in the second half, after ovulation there is a differentiation and hypertrophy of cells under the influence of corpus luteum progesterone. Lutein phase deficiency (LPD) can be divided into 3 types: lack of progesterone production (corpus luteum is absent), low progesterone level (corpus luteum hypofunction), and reduction of progesterone production period (short period of corpus luteum existence, luteal phase duration <11 days).
Objective. To describe the role of nitric oxide (NO) donors in women with LPD.
Materials and methods. Analysis of literature data on this issue.
Results and discussion. The main adverse outcome of LPD is the absence or defective transformation and reception of the endometrium required for successful fertilization of the egg. In case of progesterone deficiency, the depth of trophoblast invasion decreases, resulting in abnormal placental development and inadequate uteroplacental blood flow. The latter can further lead to antenatal foetal death and miscarriage, preeclampsia and eclampsia, placental dysfunction. LPD should be suspected in patients with infertility, abnormal uterine bleeding, severe premenstrual syndrome, endometrial hyperplasia, and habitual miscarriage. Ultrasound signs of LPD include the absence of a dominant follicle, absence of ovulation in the presence of a mature follicle (persistence), absence of corpus luteum in the 2nd phase of the cycle, endometrial thickness in the secretion phase <9 mm, increased echogenicity only in the peripheral parts of the endometrium or three-layered endometrium. Functional tests for the detection of LPD include the basal temperature measurement and examination of smears (hypolutein type of smear, preservation of the symptom of cervical mucus crystallization in the 2nd phase of the cycle). A key element of pregravid preparation for women with LPD is the progesterone donation (in oil solution, in etiloleate or micronized). The therapeutic efficacy of different commercial progesterone drugs is the same. Progesterone helps to prepare the endometrium for trophoblast invasion and promotes uterine hypotension. Incomplete secretory transformation of the endometrium during the treatment with progesterone drugs occurs in case of inadequate blood supply to the endometrium due to low density of functional vessels or insufficient content of NO in the endometrium. Back in the late 90’s of last century, it was shown that NO acts as a powerful uterine relaxant, and reduction of its concentration leads to miscarriage. In humans, NO is produced from L-arginine, however, obtaining the required dose of the latter with food is not always possible. When L-arginine (Tivortin aspartate, “Yuria-Pharm”) is used as a NO donor, peripheral vascular dilatation and neoangiogenesis occur, which improves blood supply and endometrial trophic processes; stimulation of gene transcription and cell cycle, which increases the cell population and physiological thickness of the endometrium; regulation of sex hormone synthesis and expression of their receptors, which increases the receptivity of the endometrium. The regimen of Tivortin aspartate administration is the following: 5 ml (1 g) 6 times per day during the menstrual cycle. According to the results of our own study, L-arginine increases the biological effect of progesterone on the endometrium, promotes a more successful restoration of its physiological structure and thickness in women with LPD. The inclusion of L-arginine in the pregravid preparation of women with LPD showed a 1.9-fold decrease in the infertility incidence, a 3.3-fold increase in the number of pregnancies and births, and a 3.4-fold decrease in the number of miscarriages.
Conclusions. 1. The main adverse outcome of LPD is the absence or defective transformation and reception of the endometrium required for successful fertilization of the egg. 2. Usage of L-arginine (Tivortin aspartate) as a donor of NO promotes dilatation of peripheral vessels and neoangiogenesis, stimulation of the cell cycle, regulation of the synthesis of sex hormones. 3. Inclusion of L-arginine in the pregravid preparation of women with LPD leads to the decrease in infertility, to the increase in the number of pregnancies and births and to the decrease in the number of miscarriages.
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Satué, Katiuska, Esterina Fazio, and Pietro Medica. "Can the Presence of Ovarian Corpus Luteum Modify the Hormonal Composition of Follicular Fluid in Mares?" Animals 10, no. 4 (April 9, 2020): 646. http://dx.doi.org/10.3390/ani10040646.
Full textAbstract:
The hypothesis of this study was to investigate if the presence of corpus luteum (CL) in one ovary could modify the hormonal content of follicular fluid (FF) in the follicles. Sixty ovaries were taken after the slaughter of 30 clinically healthy mares. In relation to the sizes, the follicles were classified into three different categories, as small (20–30 mm), medium (31–40 mm) and large (≥41 mm). Blood samples were collected from the jugular vein of mares before their slaughter, and then the FF samplings were extracted from each single follicle. The ovaries that were collected were classified into two groups, according to the presence (CL-bearing) or absence (non-CL-bearing) of CL. The serum and FF samples were analysed for progesterone (P4), oestradiol-17β (E2), testosterone (T), androstenedione (A4) and dehydroepiandrosterone (DHEA). Intrafollicular P4 concentrations in large follicles of CL-bearing groups were lower than for non-CL-bearing ones. Intrafollicular E2 concentrations increased with the increase of the follicle diameter in both groups, CL-bearing and non-CL-bearing. However, in the FF with a large and medium follicle size, E2 concentrations were significantly higher in non-CL-bearing groups than in CL-bearing groups. T and A4 significantly increased in the large and medium follicle sizes when compared to the small follicle sizes in both groups, but higher concentrations in the non-CL-bearing group were obtained. Intrafollicular DHEA significantly decreased with the increase of the follicular diameter in both groups. Steroid hormones in FF dynamically changed, according to the presence or not of CL in the ovary. This study brings new knowledge on the role of the CL in the follicular hormonal composition in mares.
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Hinds, LA, TP Fletcher, and JC Rodger. "Hormones of oestrus and ovulation and their manipulation in marsupials." Reproduction, Fertility and Development 8, no. 4 (1996): 661. http://dx.doi.org/10.1071/rd9960661.
Full textAbstract:
Oestrus and ovulation occur spontaneously in the majority of marsupials, with behavioural oestrus usually occurring 1-2 days before ovulation. The hormone changes that occur at this time have been described in the most detail for the monovular tammar wallaby Macropus eugenii. The respective roles of the Graafian follicle, corpus luteum and the pituitary in the events leading up to oestrus and ovulation in this species are also reviewed. Recently, various protocols have been developed for superovulation of marsupials, including Australian species, such as the brush-tailed possum, fat-tailed dunnart, brush-tailed bettong and tammar wallaby, and the American laboratory opossum, Monodelphis domestica. These protocols provide an opportunity for studying the regulation of ovarian activity and for the collection of larger quantities of material for the study of gamete maturation, in vitro fertilization and embryonic development.