Journal articles: 'Choline Kinase Inhibitor'

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Wieprecht, M., T. Wieder, and C. C. Geilen. "N-[2-bromocinnamyl(amino)ethyl]-5-isoquinolinesulphonamide (H-89) inhibits incorporation of choline into phosphatidylcholine via inhibition of choline kinase and has no effect on the phosphorylation of CTP:phosphocholine cytidylyltransferase." Biochemical Journal 297, no. 1 (January 1, 1994): 241–47. http://dx.doi.org/10.1042/bj2970241.

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We have shown previously that N-[2-bromocinnamyl(amino)-ethyl]-5-isoquinolinesulphonamide (H-89), a selective inhibitor of cyclic-AMP-dependent protein kinase (PKA), inhibits phosphatidylcholine biosynthesis in HeLa cells. In the present study, we elucidated the mechanism underlying the described inhibition. Treatment of cells with 10 microM H-89 had no effect on the phosphorylation of CTP:phosphocholine cytidylyltransferase. However, H-89 slightly affected the distribution of cytidylyltransferase between cytosol and membranes, but the cellular 1,2-diacylglycerol content was not influenced. Furthermore, pulse-chase experiments revealed that H-89 did not affect cytidylyltransferase activity. Instead, H-89 inhibited choline kinase, the enzyme catalysing the first step in the CDP-choline pathway. In the presence of 10 microM H-89, choline kinase activity was inhibited by 36 +/- 7.6% in vitro. Additionally, the phosphorylation of choline to phosphocholine was inhibited by 30 +/- 3% in cell-culture experiments. This inhibitory effect could be partly prevented by simultaneous addition of 10 microM forskolin, indicating that choline kinase is regulated in part by PKA activity.

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Zimmerman, Tahl, Juan Carlos Lacal, and Salam A. Ibrahim. "A dual choline/phosphocholine colorimetric method for measuring the relative strength of inhibitors of choline kinases of Gram-positive pathogens." Food Science and Applied Biotechnology 1, no. 2 (October 10, 2018): 131. http://dx.doi.org/10.30721/fsab2018.v1.i2.40.

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Using chemical and artificial preservation methods to keep food safe is becoming an issue with consumers. Therefore, it is important to discover antimicrobials from natural sources for use in food safety applications. The objective of the present study was to establish screening system for natural inhibitors of choline kinase (ChoK), a known antimicrobial target. A previously developed dual choline/phosphocholine colorimetric method was used to determine the relative strength of 3 choline kinase inhibitors: Hemocholinium-3, RSM-928A, and MN58 . Whole cell extracts containing the choline kinase of Streptococcus pneumoniae (sChoK) was used as a model. The measured IC50 values of these drugs were >2700 µM, 0.54 µM, and 170-225 µM, respectively. Importantly, not every step of the colorimetric method could be used in the case of every inhibitor, since each had its own particular reactive profile with the colorimetric dyes, which could have lead to confounded measurements. However, in every case, the system was flexible enough to measure choline or phosphocholine, if not both metabolites. We establish here that this dual choline/phosphocholine system is flexible enough to measure the IC50 any possible inhibitor. This colorimetric method is an ideal benchtop method for screening for natural inhibitors of bacterial ChoKs.

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Miwa, Masaichi, Atsushi Suzuki, Yasuko Watanabe, Junji Shinoda, Yutaka Oiso, and Osamu Kozawa. "Vasopressin activates phospholipase D through pertussis toxin-insensitive GTP-binding protein in aortic smooth muscle cells: function of Ca2+/calmodulin." Biochemistry and Cell Biology 73, no. 3-4 (March 1, 1995): 191–99. http://dx.doi.org/10.1139/o95-023.

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In the present study, we examined the effect of vasopressin (AVP) on phosphatidylcholine-hydrolyzing phospholipase D activity in primary cultured rat aortic smooth muscle cells. AVP stimulation of choline formation was dose dependent. The time-course was quite different from those of inositol phosphates. The effect of AVP on the formation of inositol phosphates (EC50 was 3 nM) was more potent than that on the formation of choline (EC50 was 30 nM). 12-O-Tetradecanoylphorbol-13-acetate (TPA), an activator of protein kinase C (PKC), stimulated the formation of choline. However, 4α-phorbol 12,13-didecanoate, which is inactive for PKC, had little effect. Staurosporine, an inhibitor of protein kinases, which inhibited the TPA-induced formation of choline, had little effect on the AVP-induced formation of choline. Neither calphostin C, a highly specific PKC inhibitor, nor PKC down-regulation with TPA affected AVP-induced formation of choline. A combination of AVP and TPA additively stimulated the formation of choline. The depletion of extracellular Ca2+ by (ethylenebis(oxyethylenenitrilo))tetraacetic acid significantly reduced the AVP-induced formation of choline. W-7, an antagonist of calmodulin, inhibited the AVP-induced formation of choline in a dose-dependent manner. NaF, an activator for GTP-binding protein (G-protein), stimulated the formation of choline. However, the formation of choline by a combination of AVP and NaF was not additive. Pertussis toxin had little effect on the AVP-induced formation of choline. These results strongly suggest that AVP stimulates phospholipase D in a Ca2+/calmodulin-dependent manner in aortic smooth muscle cells, that a pertussis-toxin-insensitive G-protein is involved in the AVP-induced phospholipase D activation, and furthermore, that PKC is not essential for the activation.Key words: vasopressin, phospholipase D, protein kinase C, calmodulin, GTP-binding protein, aortic smooth muscle cells.

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Zimmerman, Tahl, and Salam A. Ibrahim. "Quercetin Is a Novel Inhibitor of the Choline Kinase of Streptococcus pneumoniae." Antibiotics 11, no. 9 (September 19, 2022): 1272. http://dx.doi.org/10.3390/antibiotics11091272.

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The effectiveness of current antimicrobial methods for addressing for food-borne Gram-positive pathogens has dropped with the emergence of resistant strains. Consequently, new methods for addressing Gram-positive strains have to be developed continuously. This includes establishing novel targets for antimicrobial discovery efforts. Eukaryotic choline kinases have been highly developed as drug targets for the treatment of cancer, rheumatoid arthritis, malaria and many other conditions and diseases. Recently, choline kinase (ChoK) has been proposed as a drug target for Gram-positive species generally. The aim of this work was to discover novel, natural sources of inhibitors for bacterial ChoK from tea extracts. We report the first natural bacterial ChoK inhibitor with antimicrobial activity against Streptococcus pneumoniae: quercetin.

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Shinoda, J., A. Suzuki, Y. Oiso, and O. Kozawa. "Thromboxane A2-stimulated phospholipase D in osteoblast-like cells: possible involvement of PKC." American Journal of Physiology-Endocrinology and Metabolism 269, no. 3 (September 1, 1995): E524—E529. http://dx.doi.org/10.1152/ajpendo.1995.269.3.e524.

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We examined the effect of thromboxane A2 (TxA2) on phosphatidylcholine-hydrolyzing phospholipase D activity in osteoblast-like MC3T3-E1 cells. 9,11-Epithio-11,12-methanothromboxane A2 (STA2), a stable analogue of TxA2, stimulated the formations of both choline and inositol phosphates in a dose-dependent manner in the range between 10 nM and 10 microM. The formation of choline stimulated by a combination of STA2 and 12-O-tetradecanoylphorbol 13-acetate (TPA), a protein kinase C-activating phorbol ester, was not additive. 1-(5-Isoquinolinyl-sulfonyl)-2-methylpiperazine (H-7), an inhibitor of protein kinases, suppressed the formation of choline induced by STA2 as well as that by TPA, but 20 microM N-(2-guanidinoethyl)-5-isoquinolinesulfonamide (HA-1004), a control for H-7 as a protein kinase C inhibitor, had little effect. Calphostin C, a potent and specific inhibitor of protein kinase C, also suppressed the formation of choline induced by STA2. The STA2-induced formation of choline was significantly reduced by chelating extracellular Ca2+ with ethylene glycol-bis(beta-amino-ethyl ether)-N,N,N',N'-tetraacetic acid. STA2 dose dependently stimulated 45Ca2+ influx from extracellular space. STA2 stimulated DNA synthesis of MC3T3-E1 cells and increased the number of these cells. These results suggest that TxA2 stimulates phospholipase D in osteoblast-like cells, resulting in the direction of their proliferation, and that the activation of protein kinase C is involved in the stimulation of phospholipase D.

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Khalifa, Moad, Ling Ling Few, and Wei Cun See Too. "Phage-choline Kinase Inhibitor Combination to Control Pseudomonas aeruginosa: A Promising Combo." Mini-Reviews in Medicinal Chemistry 22, no. 9 (May 2022): 1281–88. http://dx.doi.org/10.2174/1389557521666211213160256.

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Background:: Pseudomonas aeruginosa is one of the most prevalent opportunistic pathogens in humans that has thrived and proved to be difficult to control in this “post-antibiotic era.” Antibiotic alternatives are necessary for fighting against this resilient bacterium. Even though phages might not be “the wonder drug” that solves everything, they still provide a viable option to combat P. aeruginosa and curb the threat it imposes. Main findings:: The combination of antibiotics with phages, however, poses a propitious treatment option for P. aeruginosa. Choline kinase (ChoK) is the enzyme that synthesizes phosphorylcholine subsequently incorporated into lipopolysaccharide located at the outer membrane of gram-negative bacteria. Recently, inhibition of ChoKs has been proposed as a promising antibacterial strategy. Successful docking of Hemicholinium-3, a choline kinase inhibitor, to the model structure of P. aeruginosa ChoK also supports the use of this inhibitor or its derivatives to inhibit the growth of this microorganism. Conclusion:: Therefore, the combination of the novel antimicrobial “choline kinase inhibitors (ChoKIs)” with a phage cocktail or synthetic phages as a potential treatment for P. aeruginosa infection has been proposed.

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Choubey, Vinay, Pallab Maity, Mithu Guha, Sanjay Kumar, Kumkum Srivastava, Sunil Kumar Puri, and Uday Bandyopadhyay. "Inhibition of Plasmodium falciparum Choline Kinase by Hexadecyltrimethylammonium Bromide: a Possible Antimalarial Mechanism." Antimicrobial Agents and Chemotherapy 51, no. 2 (December 4, 2006): 696–706. http://dx.doi.org/10.1128/aac.00919-06.

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ABSTRACT Choline kinase is the first enzyme in the Kennedy pathway (CDP-choline pathway) for the biosynthesis of the most essential phospholipid, phosphatidylcholine, in Plasmodium falciparum. In addition, choline kinase also plays a pivotal role in trapping essential polar head group choline inside the malaria parasite. Recently, Plasmodium falciparum choline kinase (PfCK) has been cloned, overexpressed, and purified. However, the function of this enzyme in parasite growth and survival has not been evaluated owing to the lack of a suitable inhibitor. Purified recombinant PfCK enabled us to identify an inhibitor of PfCK, hexadecyltrimethylammonium bromide (HDTAB), which has a very close structural resemblance to hexadecylphosphocholine (miltefosin), the well-known antiproliferative and antileishmanial drug. HDTAB inhibited PfCK in a dose-dependent manner and offered very potent antimalarial activity in vitro against Plasmodium falciparum. Moreover, HDTAB exhibited profound antimalarial activity in vivo against the rodent malaria parasite Plasmodium yoelii (N-67 strain). Interestingly, parasites at the trophozoite and schizont stages were found to be particularly sensitive to HDTAB. The stage-specific antimalarial effect of HDTAB correlated well with the expression pattern of PfCK in P. falciparum, which was observed by reverse transcription-PCR and immunofluorescence microscopy. Furthermore, the antimalarial activity of HDTAB paralleled the decrease in phosphatidylcholine content, which was found to correlate with the decreased phosphocholine generation. These results suggest that inhibition of choline kinase by HDTAB leads to decreased phosphocholine, which in turn causes a decrease in phosphatidylcholine biosynthesis, resulting in death of the parasite.

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Jabalera, Ylenia, Alberto Sola-Leyva, Ana Peigneux, Federica Vurro, Guillermo R. Iglesias, Jesus Vilchez-Garcia, Inmaculada Pérez-Prieto, et al. "Biomimetic Magnetic Nanocarriers Drive Choline Kinase Alpha Inhibitor inside Cancer Cells for Combined Chemo-Hyperthermia Therapy." Pharmaceutics 11, no. 8 (August 12, 2019): 408. http://dx.doi.org/10.3390/pharmaceutics11080408.

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Choline kinase α1 (ChoKα1) has become an excellent antitumor target. Among all the inhibitors synthetized, the new compound Ff35 shows an excellent capacity to inhibit ChoKα1 activity. However, soluble Ff35 is also capable of inhibiting choline uptake, making the inhibitor not selective for ChoKα1. In this study, we designed a new protocol with the aim of disentangling whether the Ff35 biological action is due to the inhibition of the enzyme and/or to the choline uptake. Moreover, we offer an alternative to avoid the inhibition of choline uptake caused by Ff35, since the coupling of Ff35 to novel biomimetic magnetic nanoparticles (BMNPs) allows it to enter the cell through endocytosis without interacting with the choline transporter. This opens the possibility of a clinical use of Ff35. Our results indicate that Ff35-BMNPs nanoassemblies increase the selectivity of Ff35 and have an antiproliferative effect. Also, we demonstrate the effectiveness of the tandem Ff35-BMNPs and hyperthermia.

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Guma, M., E. Sanchez-Lopez, A. Lodi, R. Garcia-Carbonell, S. Tiziani, M. Karin, J. C. Lacal, and G. S. Firestein. "Choline kinase inhibition in rheumatoid arthritis." Annals of the Rheumatic Diseases 74, no. 7 (October 1, 2014): 1399–407. http://dx.doi.org/10.1136/annrheumdis-2014-205696.

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ObjectivesLittle is known about targeting the metabolome in non-cancer conditions. Choline kinase (ChoKα), an essential enzyme for phosphatidylcholine biosynthesis, is required for cell proliferation and has been implicated in cancer invasiveness. Aggressive behaviour of fibroblast-like synoviocytes (FLS) in rheumatoid arthritis (RA) led us to evaluate whether this metabolic pathway could play a role in RA FLS function and joint damage.MethodsCholine metabolic profile of FLS cells was determined by 1H magnetic resonance spectroscopy (1HMRS) under conditions of ChoKα inhibition. FLS function was evaluated using the ChoKα inhibitor MN58b (IC50=4.2 μM). For arthritis experiments, mice were injected with K/BxN sera. MN58b (3 mg/kg) was injected daily intraperitoneal beginning on day 0 or day 4 after serum administration.ResultsThe enzyme is expressed in synovial tissue and in cultured RA FLS. Tumour necrosis factor (TNF) and platelet-derived growth factor (PDGF) stimulation increased ChoKα expression and levels of phosphocholine in FLS measured by Western Blot (WB) and metabolomic studies of choline-containing compounds in cultured RA FLS extracts respectively, suggesting activation of this pathway in RA synovial environment. A ChoKα inhibitor also suppressed the behaviour of cultured FLS, including cell migration and resistance to apoptosis, which might contribute to cartilage destruction in RA. In a passive K/BxN arthritis model, pharmacologic ChoKα inhibition significantly decreased arthritis in pretreatment protocols as well as in established disease.ConclusionsThese data suggest that ChoKα inhibition could be an effective strategy in inflammatory arthritis. It also suggests that targeting the metabolome can be a new treatment strategy in non-cancer conditions.

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Yasui, K., M. Yamazaki, M. Miyabayashi, T. Tsuno, and A. Komiyama. "Signal transduction pathway in human polymorphonuclear leukocytes for chemotaxis induced by a chemotactic factor. Distinct from the pathway for superoxide anion production." Journal of Immunology 152, no. 12 (June 15, 1994): 5922–29. http://dx.doi.org/10.4049/jimmunol.152.12.5922.

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Abstract The tyrosine kinase inhibitors erbstatin and herbimycin A inhibited the chemotactic response to FMLP (2 x 10(-7) M) and the superoxide anion (O2-) production stimulated by FMLP (1 x 10(-6) M) in human polymorphonuclear leukocytes (PMN) in similar manners. These compounds also inhibited phospholipase D (PLD)-catalyzed breakdown of phosphatidyl choline, suggesting a possible link between tyrosine kinase and PLD. In the presence of propranolol (phosphatidic acid (PA) phosphohydrolase inhibitor), or ethanol, the activation of PLD results in the modulation of PA and/or diglyceride (DG) generation, producing an irregularity in O2- production. However, PMN motility was not affected in these conditions. These results suggest that PLD is a downstream effector of FMLP-induced tyrosine kinase activation that leads to activation of the PMN superoxide release but not to chemotactic migration. In contrast, the tyrosine kinase inhibitors did not inhibit inositol 1,4,5-triphosphate generation and increase of intracellular concentration of free calcium. Furthermore, a protein kinase C inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7), did not affect the migration of PMN and the activation of PLD induced by FMLP at concentrations of less than 50 microM. These results support the premise that there is a specific signaling pathway for chemoattractant-induced PMN locomotion.

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Zimmerman, Tahl, Carlos Moneriz, Amalia Diez, José Manuel Bautista, Teresa Gómez del Pulgar, Arancha Cebrián, and Juan Carlos Lacal. "Antiplasmodial Activity and Mechanism of Action of RSM-932A, a Promising Synergistic Inhibitor of Plasmodium falciparum Choline Kinase." Antimicrobial Agents and Chemotherapy 57, no. 12 (September 16, 2013): 5878–88. http://dx.doi.org/10.1128/aac.00920-13.

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ABSTRACTWe have investigated the mechanism of action of inhibition of the choline kinase ofP. falciparum(p.f.-ChoK) by two inhibitors of the human ChoKα, MN58b and RSM-932A, which have previously been shown to be potent antitumoral agents. The efficacy of these inhibitors againstp.f.-ChoK is investigated using enzymatic andin vitroassays. While MN58b may enter the choline/phosphocholine binding site, RSM-932A appears to have an altogether novel mechanism of inhibition and is synergistic with respect to both choline and ATP. A model of inhibition for RSM-932A in which this inhibitor trapsp.f.-ChoK in a phosphorylated intermediate state blocking phosphate transfer to choline is presented. Importantly, MN58b and RSM-932A havein vitroinhibitory activity in the low nanomolar range and are equally effective against chloroquine-sensitive and chloroquine-resistant strains. RSM-932A and MN58b significantly reduced parasitemia and induced the accumulation of trophozoites and schizonts, blocking intraerythrocytic development and interfering with parasite egress or invasion, suggesting a delay of the parasite maturation stage. The present data provide two new potent structures for the development of antimalarial compounds and validatep.f.-ChoK as an accessible drug target against the parasite.

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HOUSTON, K. M., and W. HARNETT. "Mechanisms underlying the transfer of phosphorylcholine to filarial nematode glycoproteins – a possible role for choline kinase." Parasitology 118, no. 3 (March 1999): 311–18. http://dx.doi.org/10.1017/s0031182098003722.

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Phosphorylcholine (PC) is a common constituent of proteins secreted by filarial nematodes. As this substance has been shown to interfere with immune responses, we are interested in designing strategies for blocking its attachment. Towards this end, we are investigating the mechanism of incorporation of PC into filarial molecules and in the present manuscript we describe experiments relating to elucidating the source of PC for attachment. Synthesis of phosphatidylcholine in eukaryotic organisms can occur by a mechanism involving the transfer of PC from CDP-choline to diacylglycerol (the Kennedy pathway). By (i) measuring transfer of radio-isotope labelled PC from CDP-choline to parasite molecules and (ii) employing inhibitors of CDP-choline synthesis, we have investigated whether CDP-choline can act as a source of PC for transfer to ES–62, a major secreted glycoprotein of the rodent filarial nematode Acanthocheilonema viteae. Although we can find no evidence of this, we show that attachment of PC is blocked by hemicholinium-3, an inhibitor of choline kinase, the first enzyme in the Kennedy pathway. Thus, at least the first step in this pathway – phosphorylation of choline, would appear to be necessary for attachment of PC to ES-62.

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Zha, Xiliang, Francis T. Jay, and Patrick C. Choy. "Effects of amino acids and ethanolamine on choline uptake and phosphatidylcholine biosynthesis in baby hamster kidney-21 cells." Biochemistry and Cell Biology 70, no. 12 (December 1, 1992): 1319–24. http://dx.doi.org/10.1139/o92-179.

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The effects of amino acids and ethanolamine on choline uptake and phosphatidylcholine biosynthesis in baby hamster kidney (BHK-21) cells were investigated. The cells were incubated with labelled choline in the presence of an amino acid or ethanolamine. The uptake of labelled choline was noncompetitively inhibited by amino acids. Glycine, L-alanine, L-serine, L-leucine, L-aspartate, and L-arginine were effective inhibitors and a maximum of 22% inhibition of choline uptake was obtained with 5 mM glycine. Analyses of the labellings in the choline-containing metabolites revealed that the conversion of choline to CDP-choline and subsequently phosphatidylcholine was not affected by the presence of amino acids. The uptake of choline was also inhibited by ethanolamine in a concentration-dependent manner. Kinetic studies on the uptake of choline indicated that the inhibition by ethanolamine was competitive in nature. Although ethanolamine is a potent inhibitor of choline kinase, analyses of the labellings in the choline-containing metabolites indicated that the conversion of choline to phosphocholine was not affected in the cells incubated with ethanolamine. Ethanolamine did not change the pool sizes of phosphocholine and CDP-choline. Based on the specific radioactivity of CDP-choline and the labelling of phosphatidylcholine, the rates of phosphatidylcholine biosynthesis were not significantly different between the control and the ethanolamine-treated cells. In view of the concentrations of amino acids (millimolar) and ethanolamine (micromolar) in most cell culture media, it appeared that only amino acids were important metabolites for the regulation of choline uptake in BHK-21 cells. We conclude that both amino acids and ethanolamine have no direct effect on the biosynthesis of phosphatidylcholine.Key words: choline uptake, phosphatidylcholine biosynthesis, amino acids, ethanolamine, BHK-21 cells.

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García-Molina, Pablo, Alberto Sola-Leyva, Pilar M. Luque-Navarro, Alejandro Laso, Pablo Ríos-Marco, Antonio Ríos, Daniela Lanari, et al. "Anticancer Activity of the Choline Kinase Inhibitor PL48 Is Due to Selective Disruption of Choline Metabolism and Transport Systems in Cancer Cell Lines." Pharmaceutics 14, no. 2 (February 16, 2022): 426. http://dx.doi.org/10.3390/pharmaceutics14020426.

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A large number of different types of cancer have been shown to be associated with an abnormal metabolism of phosphatidylcholine (PC), the main component of eukaryotic cell membranes. Indeed, the overexpression of choline kinase α1 (ChoKα1), the enzyme that catalyses the bioconversion of choline to phosphocholine (PCho), has been found to associate with cell proliferation, oncogenic transformation and carcinogenesis. Hence, ChoKα1 has been described as a possible cancer therapeutic target. Moreover, the choline transporter CTL1 has been shown to be highly expressed in several tumour cell lines. In the present work, we evaluate the antiproliferative effect of PL48, a rationally designed inhibitor of ChoKα1, in MCF7 and HepG2 cell lines. In addition, we illustrate that the predominant mechanism of cellular choline uptake in these cells is mediated by the CTL1 choline transporter. A possible correlation between the inhibition of both choline uptake and ChoKα1 activity and cell proliferation in cancer cell lines is also highlighted. We conclude that the efficacy of this inhibitor on cell proliferation in both cell lines is closely correlated with its capability to block choline uptake and ChoKα1 activity, making both proteins potential targets in cancer therapy.

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Young, Robin K., and Alice R. A. Villalobos. "Stress-induced stimulation of choline transport in cultured choroid plexus epithelium exposed to low concentrations of cadmium." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 306, no. 5 (March 1, 2014): R291—R303. http://dx.doi.org/10.1152/ajpregu.00252.2013.

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The choroid plexus epithelium forms the blood-cerebrospinal fluid barrier and accumulates essential minerals and heavy metals. Choroid plexus is cited as being a “sink” for heavy metals and excess minerals, serving to minimize accumulation of these potentially toxic agents in the brain. An understanding of how low doses of contaminant metals might alter transport of other solutes in the choroid plexus is limited. Using primary cultures of epithelial cells isolated from neonatal rat choroid plexus, our objective was to characterize modulation of apical uptake of the model organic cation choline elicited by low concentrations of the contaminant metal cadmium (CdCl2). At 50–1,000 nM, cadmium did not directly decrease or increase 30-min apical uptake of 10 μM [3H]choline. However, extended exposure to 250–500 nM cadmium increased [3H]choline uptake by as much as 75% without marked cytotoxicity. In addition, cadmium induced heat shock protein 70 and heme oxygenase-1 protein expression and markedly induced metallothionein gene expression. The antioxidant N-acetylcysteine attenuated stimulation of choline uptake and induction of stress proteins. Conversely, an inhibitor of glutathione synthesis l-buthionine-sulfoximine (BSO) enhanced stimulation of choline uptake and induction of stress proteins. Cadmium also activated ERK1/2 MAP kinase. The MEK1 inhibitor PD98059 diminished ERK1/2 activation and attenuated stimulation of choline uptake. Furthermore, inhibition of ERK1/2 activation abated stimulation of choline uptake in cells exposed to cadmium with BSO. These data indicate that in the choroid plexus, exposure to low concentrations of cadmium may induce oxidative stress and consequently stimulate apical choline transport through activation of ERK1/2 MAP kinase.

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Kall, Stefanie L., Edward J. Delikatny, and Arnon Lavie. "Identification of a Unique Inhibitor-Binding Site on Choline Kinase α." Biochemistry 57, no. 8 (February 8, 2018): 1316–25. http://dx.doi.org/10.1021/acs.biochem.7b01257.

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Cook, S. J., and M. J. O. Wakelam. "Epidermal growth factor increases sn-1,2-diacylglycerol levels and activates phospholipase D-catalysed phosphatidylcholine breakdown in Swiss 3T3 cells in the absence of inositol-lipid hydrolysis." Biochemical Journal 285, no. 1 (July 1, 1992): 247–53. http://dx.doi.org/10.1042/bj2850247.

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Addition of epidermal growth factor (EGF) to quiescent Swiss 3T3 cells resulted in a sustained increase in cellular diacylglycerol (DG) content in the absence of inositol-lipid hydrolysis. In the presence of non-cytotoxic concentrations of butan-1-ol, EGF stimulated the formation of phosphatidylbutanol, indicating that the EGF receptor was able to couple to the activation of phospholipase D (PLD). EGF-stimulated release of choline from Swiss 3T3 cells suggested that the major substrate for this PLD was phosphatidylcholine. Unlike bombesin-stimulated PLD activity, the response to EGF was not inhibited by a selective protein kinase C (PKC) inhibitor (Ro-31-8220), suggesting that it was not dependent on PKC activation. Pre-treatment of Swiss 3T3 cells with the EGF-receptor tyrosine kinase inhibitor AG18 selectively inhibited EGF-stimulated PLD activity; bombesin-stimulated PLD activity was unaffected. Butan-1-ol inhibited phorbol ester- and bombesin-stimulated DG formation suggesting a role for a coupled PLD/phosphatidate phosphohydrolase pathway; in contrast, EGF-stimulated DG formation was unaffected.

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Rydzewska, G., B. Rossignol, and J. Morisset. "Involvement of phospholipase D in caerulein-induced phosphatidylcholine hydrolysis in rat pancreatic acini." American Journal of Physiology-Gastrointestinal and Liver Physiology 265, no. 4 (October 1, 1993): G725—G734. http://dx.doi.org/10.1152/ajpgi.1993.265.4.g725.

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Phosphatidylcholine (PC) metabolism stimulated by caerulein (Cae), a cholecystokinin analogue, was investigated in rat pancreatic acini prelabeled with [3H]choline or [3H]-myristic acid. Both labels were incorporated mostly into PC. An inhibition of choline incorporation into PC was first observed in response to Cae (100 and 500 pM) stimulation, as indicated by reduced [3H]choline incorporation into trichloroacetic acid-precipitable material. Whereas choline incorporation was reduced in PC, Cae (500 pM) significantly increased [3H]choline metabolites release in the incubation medium. Separation of these metabolites by thin-layer chromatography showed that approximately 90% of the labeled products released into the medium was phosphocholine; however, Cae caused significant increases of [3H]choline release after 5, 15, and 30 min. In response to Cae, manoalide, a phospholipase C (PLC) inhibitor, totally prevented phosphocholine release into the medium but did not affect choline release. Staurosporine, a protein kinase C inhibitor, did not influence basal and Cae-induced choline release. In cells prelabeled with [3H]myristic acid, Cae stimulated within 5 min a rapid increase in intracellular [3H]phosphatidic acid (PA) levels in the presence of the PA phosphohydrolase inhibitor, propranolol; this PA production was further increased after 15 and 30 min of stimulation. The time course of [3H]PA formation in the presence of propranolol was similar to that of choline release in the medium. Staurosporine partially blocked PA accumulation stimulated by Cae after 30 min. In contrast, manoalide significantly reduced basal PA accumulation but did not prevent its production in response to Cae. In the presence of ethanol, Cae also significantly stimulated above control values the formation of [3H]phosphatidylethanol. These data indicate that Cae-induced PC hydrolysis in rat pancreatic acini is mediated mostly by phospholipase D (PLD) to produce PA and choline; they suggest a direct action of Cae on PLD activation, an effect independent of PLC activation

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Suzuki, A., J. Shinoda, Y. Oiso, and O. Kozawa. "Mechanism of phospholipase D activation induced by extracellular ATP in osteoblast-like cells." Journal of Endocrinology 145, no. 1 (April 1995): 81–86. http://dx.doi.org/10.1677/joe.0.1450081.

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Abstract We have previously reported that extracellular ATP stimulates Ca2+ influx from extracellular space, resulting in the production of prostaglandin E2 which mediates, at least in part, its proliferative effect on osteoblast-like MC3T3-E1 cells, and that the activation of protein kinase C (PKC) stimulates phospholipase D in these cells. In the present study, we examined the effect of extracellular ATP on phosphatidylcholine-hydrolysing phospholipase D activity in MC3T3-E1 cells. ATP stimulated the formation of both choline and inositol phosphates dose-dependently in the range between 0·1 and 1 mm. The formation of choline by a combination of ATP and NaF, an activator of GTP-binding protein, was synergistic, whereas that of inositol phosphates was not. A combination of ATP and 12-O-tetradecanoylphorbol-13-acetate, a PKC activating phorbol ester, additively stimulated the formation of choline. Staurosporine, an inhibitor of PKC, had little effect on ATP-stimulated formation of choline. Choline formation was significantly reduced by chelating extracellular Ca2+ with EGTA, while being inhibited by W-7, an antagonist of calmodulin. These results suggest that extracellular ATP stimulates phospholipase D in a Ca2+/calmodulin-dependent manner in osteoblast-like cells, and that neither PKC activation nor GTP-binding protein is involved in this mechanism. Journal of Endocrinology (1995) 145, 81–86

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Al-Saffar, Nada M. S., L. Elizabeth Jackson, Florence I. Raynaud, Paul A. Clarke, Ana Ramírez de Molina, Juan C. Lacal, Paul Workman, and Martin O. Leach. "The Phosphoinositide 3-Kinase Inhibitor PI-103 Downregulates Choline Kinase α Leading to Phosphocholine and Total Choline Decrease Detected by Magnetic Resonance Spectroscopy." Cancer Research 70, no. 13 (June 15, 2010): 5507–17. http://dx.doi.org/10.1158/0008-5472.can-09-4476.

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Bao, Hui-Fang, Zhi-Ren Zhang, You-You Liang, Joshua J. Ma, Douglas C. Eaton, and He-Ping Ma. "Ceramide mediates inhibition of the renal epithelial sodium channel by tumor necrosis factor-α through protein kinase C." American Journal of Physiology-Renal Physiology 293, no. 4 (October 2007): F1178—F1186. http://dx.doi.org/10.1152/ajprenal.00153.2007.

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To determine whether ceramide mediates regulation of the renal epithelial sodium channel (ENaC) by tumor necrosis factor-α (TNF-α), confocal microscopy and patch-clamp experiments were performed in A6 distal nephron cells. We found that TNF-α (100 ng/ml) had no effect on ENaC activity and ceramide level when the cells were grown in the presence of aldosterone, but significantly inhibited ENaC and induced ceramide production after the cells were pretreated with LY 294002, an inhibitor of phosphatidylinositol 3-kinase, for 24 h. The inhibition of ENaC induced by TNF-α was mimicked by exogenous sphingomyelinase (0.1 U/ml) and C2-ceramide (50 μM), but neither C2-dihydroceramide, a membrane-impermeable analog of C2-ceramide, nor choline, and abolished by pretreatment with GF109203X, a protein kinase C (PKC) inhibitor. C2-ceramide failed to affect ENaC in the cells pretreated with GF109203X, but not in the cells pretreated with PD-98059, a mitogen-activated protein kinase kinase inhibitor. C2-ceramide induced the externalization of phosphatidylserine (PS) in control A6 cells, but not in the cells pretreated with GF109203X. Together with our previous finding that cytosolic PS maintains ENaC activity in A6 cells, these data suggest that ceramide mediates TNF-α inhibition of the renal ENaC via a pathway associated with PKC-dependent externalization of PS.

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Wang, Ning, Diana Brickute, Marta Braga, Chris Barnes, Haonan Lu, Louis Allott, and Eric O. Aboagye. "Novel Non-Congeneric Derivatives of the Choline Kinase Alpha Inhibitor ICL-CCIC-0019." Pharmaceutics 13, no. 7 (July 14, 2021): 1078. http://dx.doi.org/10.3390/pharmaceutics13071078.

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Choline kinase alpha (CHKA) is a promising target for the development of cancer therapeutics. We have previously reported ICL-CCIC-0019, a potent CHKA inhibitor with high cellular activity but with some unfavorable pharmacological properties. In this work, we present an active analogue of ICL-CCIC-0019 bearing a piperazine handle (CK146) to facilitate further structural elaboration of the pharmacophore and thus improve the biological profile. Two different strategies were evaluated in this study: (1) a prodrug approach whereby selective CHKA inhibition could be achieved through modulating the activity of CK146, via the incorporation of an ε-(Ac) Lys motif, cleavable by elevated levels of histone deacetylase (HDAC) and cathepsin L (CTSL) in tumour cells; (2) a prostate-specific membrane antigen (PSMA) receptor targeted delivery strategy. Prodrug (CK145) and PSMA-targeted (CK147) derivatives were successfully synthesized and evaluated in vitro. While the exploitation of CK146 in those two strategies did not deliver the expected results, important and informative structure-activity relationships were observed and have been reported.

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Vernon, R. G. "GH inhibition of lipogenesis and stimulation of lipolysis in sheep adipose tissue: involvement of protein serine phosphorylation and dephosphorylation and phospholipase C." Journal of Endocrinology 150, no. 1 (July 1996): 129–40. http://dx.doi.org/10.1677/joe.0.1500129.

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Abstract The intracellular signalling systems involved in the chronic insulin-antagonistic, anti-lipogenic effects and also the lipolytic effect of GH have been investigated in sheep adipose tissue in an in vitro tissue culture system. During culture, chronic exposure to GH decreased the rate of lipogenesis and prevented the increase in lipogenesis induced by insulin. GH also increased glycerol release into the culture medium. GH had no acute, insulin-like effect on lipogenesis in sheep adipose tissue. Pretreatment with phorbol ester to down-regulate isoforms of protein kinase C or addition of the protein serine kinase inhibitor staurosporine decreased the anti-lipogenic effect of GH while the protein serine kinase inhibitor H7 eliminated it completely. Pretreatment with phorbol ester or addition of H7 also decreased the insulin-antagonistic effect of GH on lipogenesis. Addition of the protein serine phosphatase inhibitor okadaic acid or the phosphatidyl choline phospholipase C inhibitor D609 both diminished the anti-lipogenic and insulin-antagonistic effects of GH. Chronic exposure of adipose tissue to GH had no effect on the total activity of acetyl CoA carboxylase or its activation status but it did diminish the increase in activation status induced by insulin. H7 and okadaic acid also diminished the increase in activation status of acetyl CoA carboxylase induced by insulin but did not alter the effect of GH on this variable. Okadaic acid decreased total acetyl CoA carboxylase activity. Pretreatment with phorbol ester or the addition of H7, staurosporine or okadaic acid increased glycerol release into the culture medium to the same extent as GH itself; the effects of GH and these various agents were not additive. These studies suggest that the anti-lipogenic, insulin-antagonistic effects of GH involve both protein serine kinases and phosphatases, possibly including one or more isoforms of protein kinase C, and a phosphatidyl choline-specific phospholipase C. Comparison with studies by others on the GH enhancement of preadipocyte differentiation and prolactin stimulation of lipogenesis in mammary tissue suggests involvement of protein kinase C at an early stage in all three systems. In contrast, effects of okadaic acid vary with the system, suggesting the involvement of protein serine phosphatase activity in a late stage of the action of GH. The effects of GH on lipogenesis and lipolysis do not occur via identical mechanisms. Journal of Endocrinology (1996) 150, 129–140

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Koike, T., K. Hirai, Y. Morita, and Y. Nozawa. "Stem cell factor-induced signal transduction in rat mast cells. Activation of phospholipase D but not phosphoinositide-specific phospholipase C in c-kit receptor stimulation." Journal of Immunology 151, no. 1 (July 1, 1993): 359–66. http://dx.doi.org/10.4049/jimmunol.151.1.359.

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Abstract Stem cell factor (SCF), a hematopoietic growth factor for primitive hematopoietic stem cells, is also known as mast cell growth factor. SCF induced serotonin release from rat peritoneal mast cells, connective tissue-type mast cells. The treatment of rat peritoneal mast cells with SCF failed to produce inositol 1,4,5-trisphosphate, indicating the absence of involvement of phosphoinositide-specific phospholipase C pathway. 1,2-Diacylglycerol (1,2-DG) and phosphatidic acid, however, were increased after stimulation by SCF. Phosphatidylethanol formation catalyzed by phospholipase D (PLD) was observed, together with the release of choline but not phosphocholine. Propranolol, an inhibitor of phosphatidate phosphohydrolase, blocked the production of 1,2-DG. These results indicate that the phosphatidylcholine-specific PLD pathway is the main pathway for the production of 1,2-DG in SCF-stimulated rat peritoneal mast cells. Furthermore, treatment of cells with protein tyrosine kinase inhibitor, genistein, inhibited 1,2-DG formation and serotonin release dose-dependently. Taken together, SCF induces the activation of PLD through the protein tyrosine kinase pathway without activation of phosphoinositide-specific phospholipase C.

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Kiss, Z., and E. Deli. "Regulation of phospholipase D by sphingosine involves both protein kinase C-dependent and -independent mechanisms in NIH 3T3 fibroblasts." Biochemical Journal 288, no. 3 (December 15, 1992): 853–58. http://dx.doi.org/10.1042/bj2880853.

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Previously, the protein kinase C (PKC) inhibitor sphingosine was found to stimulate phospholipase D (PLD)-mediated hydrolysis of both phosphatidylethanolamine (PtdEtn) and phosphatidylcholine (PtdCho) in NIH 3T3 fibroblasts [Kiss & Anderson (1990) J. Biol. Chem. 265, 7345-7350]. Here we examined the possible relationship between the opposite effects of sphingosine on PKC-mediated protein phosphorylation and PLD activation. After treatments for 3-5 min, sphingosine (25 microM) and the PKC activators phorbol 12-myristate 13-acetate (PMA) (100 nM), bryostatin (100 nM) or platelet-derived growth factor (50 ng/ml) synergistically stimulated the hydrolysis of both PtdEtn and PtdCho in NIH 3T3 fibroblasts prelabelled with [14C]ethanolamine or [14C]choline. Inhibition of PMA-induced phospholipid hydrolysis could also be elicited by sphingosine, but this process required prolonged (60 min) treatments of fibroblasts with 40-60 microM-sphingosine. Similarly to sphingosine, the protein phosphatase inhibitor okadaic acid also had either potentiating or inhibitory effects on PMA-stimulated PLD activity, depending on the length of incubation time and the concentration of PMA. Consistent with the presence of an inhibitory component in the overall action of PKC, the PKC inhibitor staurosporine and down-regulation of PKC activity by prolonged (24 h) treatment with PMA similarly enhanced PLD activity. Data suggest that (a) sphingosine may enhance PMA-mediated phospholipid hydrolysis by neutralizing the action of an inhibitory PKC isoform, and that (b) the stimulatory PKC isoform is less sensitive to the inhibitory action of sphingosine.

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Hua, Wan, Sarantos Kostidis, Oleg Mayboroda, Martin Giera, Marten Hornsveld, and Peter ten Dijke. "Metabolic Reprogramming of Mammary Epithelial Cells during TGF-β-Induced Epithelial-to-Mesenchymal Transition." Metabolites 11, no. 9 (September 15, 2021): 626. http://dx.doi.org/10.3390/metabo11090626.

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The cytokine transforming growth factor-β (TGF-β) can induce normal breast epithelial cells to take on a mesenchymal phenotype, termed epithelial-to-mesenchymal transition (EMT). While the transcriptional and proteomic changes during TGF-β-induced EMT have been described, the metabolic rewiring that occurs in epithelial cells undergoing EMT is not well understood. Here, we quantitively analyzed the TGF-β-induced metabolic reprogramming during EMT of non-transformed NMuMG mouse mammary gland epithelial cells using nuclear magnetic resonance (NMR) spectroscopy. We found that TGF-β elevates glycolytic and tricarboxylic acid (TCA)-cycle activity and increases glutaminolysis. Additionally, TGF-β affects the hexosamine pathway, arginine-proline metabolism, the cellular redox state, and strongly affects choline metabolism during EMT. TGF-β was found to induce phosphocholine production. A kinase inhibitor RSM-93A that inhibits choline kinase α (CHKα) mitigated TGF-β-induced changes associated with EMT, i.e., increased filamentous (F)-actin stress fiber formation and N-Cadherin mesenchymal marker expression.

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Gobeil Odai, Kaelan, Conor O’Dwyer, Rineke Steenbergen, Tyler A. Shaw, Tyler M. Renner, Peyman Ghorbani, Mojgan Rezaaifar, et al. "In Vitro Hepatitis C Virus Infection and Hepatic Choline Metabolism." Viruses 12, no. 1 (January 16, 2020): 108. http://dx.doi.org/10.3390/v12010108.

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Choline is an essential nutrient required for normal neuronal and muscular development, as well as homeostatic regulation of hepatic metabolism. In the liver, choline is incorporated into the main eukaryotic phospholipid, phosphatidylcholine (PC), and can enter one-carbon metabolism via mitochondrial oxidation. Hepatitis C virus (HCV) is a hepatotropic positive-strand RNA virus that similar to other positive-strand RNA viruses and can impact phospholipid metabolism. In the current study we sought to interrogate if HCV modulates markers of choline metabolism following in vitro infection, while subsequently assessing if the inhibition of choline uptake and metabolism upon concurrent HCV infection alters viral replication and infectivity. Additionally, we assessed whether these parameters were consistent between cells cultured in fetal bovine serum (FBS) or human serum (HS), conditions known to differentially affect in vitro HCV infection. We observed that choline transport in FBS- and HS-cultured Huh7.5 cells is facilitated by the intermediate affinity transporter, choline transporter-like family (CTL). HCV infection in FBS, but not HS-cultured cells diminished CTL1 transcript and protein expression at 24 h post-infection, which was associated with lower choline uptake and lower incorporation of choline into PC. No changes in other transporters were observed and at 96 h post-infection, all differences were normalized. Reciprocally, limiting the availability of choline for PC synthesis by use of a choline uptake inhibitor resulted in increased HCV replication at this early stage (24 h post-infection) in both FBS- and HS-cultured cells. Finally, in chronic infection (96 h post-infection), inhibiting choline uptake and metabolism significantly impaired the production of infectious virions. These results suggest that in addition to a known role of choline kinase, the transport of choline, potentially via CTL1, might also represent an important and regulated process during HCV infection.

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Kim, Sang Yong, Peyman Ghorbani, Daniel Woo, Morgan D. Fullerton, and Meera G. Nair. "Choline metabolism promotes M2 macrophage polarization in intestinal infection with helminth Heligmosomoides polygyrus." Journal of Immunology 208, no. 1_Supplement (May 1, 2022): 165.05. http://dx.doi.org/10.4049/jimmunol.208.supp.165.05.

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Abstract Choline is an essential nutrient functioning as a precursor for membrane phospholipid. In previous studies, LPS polarization augmented both the expression of the choline transporter CTL1 and choline uptake, while specific inhibition of choline transport led to increased TNFα and IL-6. However, whether choline metabolism regulates M2 macrophage polarization or Th2 cytokine inflammation in vivo is unclear. In vitro, CTL1 and phospholipid synthesis was induced in IL-4 polarized M2 macrophages. To determine the function of choline metabolism in M2 polarization in vivo, mice were infected with Heligmosomoides polygyrus, intraperitoneally injected with choline kinase α inhibitor, RSM-932A or vehicle, and sacrificed at day 17 post-infection. RSM-932A treatment impaired weight gain and peritoneal exudate cell numbers in both naïve and infected mice. Within the peritoneal cavity of infected mice, macrophages and B-1 lymphocytes were depleted by RSM-932A treatment, while monocytes and neutrophils were increased. Flow cytometric and intestinal immunofluorescence staining revealed that RSM-932A treatment prevented M2 macrophage polarization in H.polygyrus-infected mice with a significant reduction in expression of PD-L2 and CD206, and conversely increased expression of CD86 and PD-L1. Additionally, RELMα protein in the serum and peritoneal fluid was downregulated by RSM-932A treatment. The impaired M2 polarization was associated with some loss in optimal immunity to H.polygyrus with increased parasite egg burden but no differences in intestinal worm count. This study indicates that choline metabolism is required for M2 macrophage polarization and an optimal immune response against intestinal helminth infection.

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Conejo-García, Ana, Antonio Entrena, Joaquín M. Campos, Rosario M. Sánchez-Martín, Miguel A. Gallo, and Antonio Espinosa. "Towards a model for the inhibition of choline kinase by a new type of inhibitor." European Journal of Medicinal Chemistry 40, no. 3 (March 2005): 315–19. http://dx.doi.org/10.1016/j.ejmech.2004.09.016.

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Ward, D. T., J. Ohanian, A. M. Heagerty, and V. Ohanian. "Phospholipase D-induced phosphatidate production in intact small arteries during noradrenaline stimulation: involvement of both G-protein and tyrosine-phosphorylation-linked pathways." Biochemical Journal 307, no. 2 (April 15, 1995): 451–56. http://dx.doi.org/10.1042/bj3070451.

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To investigate membrane lipid metabolism during smooth-muscle activation, the role of phospholipase D (PLD) in the production of phosphatidate (PA) was studied in rat small arteries stimulated with noradrenaline. Incubation with [3H]myristate preferentially labelled phosphatidylcholine (PtdCho), and in the presence of 0.5% ethanol [3H]phosphatidylethanol ([3H]PEt) was formed, demonstrating PLD activity. Noradrenaline (NA) stimulation resulted in an increase in PtdCho derived [3H]PA and [3H]PEt formation, indicating PLD activation. Stimulation of [14C]choline release confirmed PLD-mediated hydrolysis of PtdCho. Propranolol, an inhibitor of PA phosphohydrolase, increased [3H]PA levels in non-stimulated tissue and decreased the rate of degradation of both [3H]PA and [3H]PEt, implying that this is an active route for PA metabolism in small arteries. However, [3H]diacylglycerol levels were not increased during NA stimulation. Fluoroaluminate increased [3H]PEt formation and [14C]choline release, whereas high K+ in the presence of alpha 1-adrenoceptor blockade did not. Pervanadate increased phosphotyrosine levels in small arteries, and markedly stimulated [3H]PEt formation and [14C]choline release. The combination of pervanadate and NA stimulation resulted in a dramatic increase in [3H]PEt formation, which was greater than the sum of the individual responses to the two agonists. Pervanadate and fluoroaluminate in combination appeared to give an additive response, whereas high K+ did not alter the pervanadate-induced formation of [3H]PEt. Phosphotyrosine levels were increased by NA in the presence of tyrosine phosphatase inhibitors. This effect was blocked by genistein, a tyrosine kinase inhibitor. These data demonstrate that in NA-stimulated small arteries PLD-induced PtdCho hydrolysis contributes to accumulation of PA, but not of diacylglycerol. Furthermore, regulation of PLD activity appears to require G-protein and tyrosine-phosphorylation-linked pathways.

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Espinos, Estelle, Agathe Le Van Thaï, Christelle Pomiès, and Michel J. Weber. "Cooperation between Phosphorylation and Acetylation Processes in Transcriptional Control." Molecular and Cellular Biology 19, no. 5 (May 1, 1999): 3474–84. http://dx.doi.org/10.1128/mcb.19.5.3474.

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ABSTRACT We previously reported that the activation of the M promoter of the human choline acetyltransferase (ChAT) gene by butyrate and trapoxin in transfected CHP126 cells is blocked by PD98059, a specific mitogen-activated protein kinase kinase (MEK) inhibitor (E. Espinos and M. J. Weber, Mol. Brain Res. 56:118–124, 1998). We now report that the transcriptional effects of histone deacetylase inhibitors are mediated by an H7-sensitive serine/threonine protein kinase. Activation of the ChAT promoter by butyrate and trapoxin was blocked by 50 μM H7 in both transient- and stable-transfection assays. Overexpression of p300, a coactivator protein endowed with histone acetyltransferase activity, stimulated the ChAT promoter and had a synergistic effect on butyrate treatment. These effects were blocked by H7 and by overexpressed adenovirus E1A 12S protein. Moreover, both H7 and PD98059 suppressed the activation of the Rous sarcoma virus (RSV) and simian virus 40 promoters by butyrate in transfection experiments. Similarly, the induction of the cellular histone H10 gene by butyrate in CHP126 cells was blocked by H7 and by PD98059. Previous data (L. Cuisset, L. Tichonicky, P. Jaffray, and M. Delpech, J. Biol. Chem. 272:24148–24153, 1997) showed that the induction of the H10 gene by butyrate is blocked by okadaic acid, an inhibitor of protein phosphatases. We now show that the activation of the ChAT and RSV promoters by butyrate in transfected CHP126 cells is also blocked by 200 nM okadaic acid. Western blotting and in vivo metabolic labeling experiments showed that butyrate has a biphasic effect on histone H3 phosphorylation, i.e., depression for up to 16 h followed by stimulation. The data thus strongly suggest that the transcriptional effects of histone deacetylase inhibitors are mediated through the activation of MEK1 and of an H7-sensitive protein kinase in addition to protein phosphatases.

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Trousil, Sebastian, Maciej Kaliszczak, Zachary Schug, Quang-De Nguyen, Giampaolo Tomasi, Rosy Favicchio, Diana Brickute, et al. "The novel choline kinase inhibitor ICL-CCIC-0019 reprograms cellular metabolism and inhibits cancer cell growth." Oncotarget 7, no. 24 (May 19, 2016): 37103–20. http://dx.doi.org/10.18632/oncotarget.9466.

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Al-Saffar, Nada M. S., Helen Troy, Ana Ramírez de Molina, Laura E. Jackson, Basetti Madhu, John R. Griffiths, Martin O. Leach, et al. "Noninvasive Magnetic Resonance Spectroscopic Pharmacodynamic Markers of the Choline Kinase Inhibitor MN58b in Human Carcinoma Models." Cancer Research 66, no. 1 (January 1, 2006): 427–34. http://dx.doi.org/10.1158/0008-5472.can-05-1338.

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GUEGUEN, Geneviéve, Virginie GRANCI, Pierre ROGALLE, Fabienne BRIAND-MÉSANGE, Michéle WILSON, Alain KLAÉBÉ, François TERCÉ, et al. "A lysophosphatidic acid analogue is revealed as a potent inhibitor of phosphatidylcholine synthesis, inducing apoptosis." Biochemical Journal 368, no. 2 (December 1, 2002): 447–59. http://dx.doi.org/10.1042/bj20020273.

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A previous study demonstrated that cross-desensitization experiments performed with the lysophosphatidic acid (LPA) analogues (R)- and (S)-N-palmitoyl-norleucinol 1-phosphate (PNPAs) inhibited LPA-induced platelet aggregation without any stereospecificity. Here we report opposite biological effects of the two enantiomers on mitogenesis of IMR-90 fibroblasts in relation to their respective metabolism. (R)PNPA was proliferative, while (S)PNPA induced apoptosis by specifically inhibiting phosphatidylcholine biosynthesis at the last step of the CDP-choline pathway controlled by cholinephosphotransferase. This effect was not direct but required dephosphorylation of PNPAs by ecto-lipid phosphate phosphatase before cellular uptake of the generated N-palmitoyl-norleucinols (PNOHs). Inhibition of cholinephosphotransferase by the derivative (S)PNOH was confirmed by an in vitro assay. (S)PNPA proapoptotic effects led us to clarify the mechanism linking cholinephosphotransferase inhibition to apoptosis. Three proapoptotic responses were observed: the activation of caspase-3, the production of ceramides from newly synthesized pools (as demonstrated by the inhibitor Fumonisin B1) and finally the activation of stress-activated protein kinase, p38 and c-Jun N-terminal kinases 1/2, as a result of ceramide increase. Thus our data demonstrate that synthetic analogues of LPA might display stereospecific effects leading to apoptosis independently of classical LPA-activated pathways.

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Slotki, I. N., J. H. Schwartz, and E. A. Alexander. "Na(+)-H+ exchange is stimulated by protein kinase C activation in inner medullary collecting duct cells." American Journal of Physiology-Renal Physiology 259, no. 4 (October 1, 1990): F666—F671. http://dx.doi.org/10.1152/ajprenal.1990.259.4.f666.

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In this study we investigated the role of protein kinases in activation of the Na(+)-H+ exchanger in inner medullary collecting duct (IMCD) cells. Monolayers, 24-48 h after achieving confluence, were made quiescent by 24 h incubation in 0.1% serum before study. Changes in pHi were measured with 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein. Phorbol myristate acetate (PMA), a synthetic analogue of diacylglycerol (DAG), was used to stimulate protein kinase C (PKC). In nominally HCO3(-)-free media containing 110 mM Na+ and 1 mM Ca2+, PMA addition increased pHi from 7.29 +/- 0.08 to 7.54 +/- 0.07 after 20 min. The increment in pHi was completely inhibited by 1 mM amiloride or by replacement of extracellular Na+ with choline but not inhibited by 1 mM N-ethylmaleimide, an inhibitor of active proton transport. Downregulation of PKC by overnight incubation of monolayers with PMA also prevented the rise in pHi upon subsequent challenge with PMA. Another active analogue of DAG, 1,2-dioleoyl-rac-glycerol, caused an increment in pHi similar to that produced by PMA, whereas 4 alpha-phorbol, an inactive analogue, did not stimulate Na(+)-H+ exchange. Bradykinin (10(-6) M), a phospholipase C-activating hormone, also induces alkalinization of IMCD cells similar to that produced by phorbol esters. Neither vasopressin (10(-7) M), which induces cellular accumulation of adenosine 3-,5--cyclic monophosphate (cAMP) and activation of protein kinase A (PKA), nor 8-bromo-cAMP (1 mM) changed pHi. Therefore in the IMCD cell activation of PKC but not PKA stimulates a rise in pHi via the Na(+)-H+ exchanger.

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Lin, Gigin, Kun-Ju Lin, Frank Wang, Tse-Ching Chen, Tzu-Chen Yen, and Ta-Sen Yeh. "Synergistic antiproliferative effects of an mTOR inhibitor (rad001) plus gemcitabine on cholangiocarcinoma by decreasing choline kinase activity." Disease Models & Mechanisms 11, no. 8 (April 12, 2018): dmm033050. http://dx.doi.org/10.1242/dmm.033050.

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Trousil, S., M. Kaliszczak, L. Carroll, and E. O. Aboagye. "185 ICL-CCIC-0019, a Novel and Selective Inhibitor of Choline Kinase Alpha with Significant Antitumor Activity." European Journal of Cancer 48 (November 2012): 56. http://dx.doi.org/10.1016/s0959-8049(12)71983-4.

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Pahud, Gabrielle, Séverine Bontron, and Lorenza Eder-Colli. "Modulation of choline acetyltransferase synthesis by okadaic acid, a phosphatase inhibitor, and KN-62, a CaM kinase inhibitor, in NS-20Y neuroblastoma." Neurochemistry International 38, no. 1 (January 2001): 75–82. http://dx.doi.org/10.1016/s0197-0186(00)00064-4.

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Mariotto, Elena, Giampietro Viola, Roberto Ronca, Luca Persano, Sanja Aveic, Zaver Bhujwalla, Noriko Mori, et al. "Choline Kinase Alpha Inhibition by EB-3D Triggers Cellular Senescence, Reduces Tumor Growth and Metastatic Dissemination in Breast Cancer." Cancers 10, no. 10 (October 22, 2018): 391. http://dx.doi.org/10.3390/cancers10100391.

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Choline kinase (ChoK) is the first enzyme of the Kennedy pathway leading to the biosynthesis of phosphatidylcholine (PtdCho), the most abundant phospholipid in eukaryotic cell membranes. EB-3D is a novel choline kinase α1 (ChoKα1) inhibitor with potent antiproliferative activity against a panel of several cancer cell lines. ChoKα1 is particularly overexpressed and hyperactivated in aggressive breast cancer. By NMR analysis, we demonstrated that EB-3D is able to reduce the synthesis of phosphocholine, and using flow cytometry, immunoblotting, and q-RT-PCR as well as proliferation and invasion assays, we proved that EB-3D strongly impairs breast cancer cell proliferation, migration, and invasion. EB-3D induces senescence in breast cancer cell lines through the activation of the metabolic sensor AMPK and the subsequent dephosphorylation of mTORC1 downstream targets, such as p70S6K, S6 ribosomal protein, and 4E-BP1. Moreover, EB-3D strongly synergizes with drugs commonly used for breast cancer treatment. The antitumorigenic potential of EB-3D was evaluated in vivo in the syngeneic orthotopic E0771 mouse model of breast cancer, where it induces a significant reduction of the tumor mass at low doses. In addition, EB-3D showed an antimetastatic effect in experimental and spontaneous metastasis models. Altogether, our results indicate that EB-3D could be a promising new anticancer agent to improve aggressive breast cancer treatment protocols.

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Radika, K., and F. Possmayer. "Inhibition of foetal pulmonary choline-phosphate cytidylyltransferase under conditions favouring protein phosphorylation." Biochemical Journal 232, no. 3 (December 15, 1985): 833–40. http://dx.doi.org/10.1042/bj2320833.

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Choline-phosphate cytidylyltransferase (EC 2.7.7.15) activity from 25- and 29-day-foetal rabbit lungs was inhibited in both the cytosolic and the microsomal fractions by preincubation with MgATP. The inhibition of the cytosolic enzyme was greater when measured with added phosphatidylglycerol (PG) than without (78-89% versus 50-55%), whereas the inhibition of the microsomal enzyme did not exhibit this distinction (66-72% versus 60-70%). When preincubated with the buffer alone, the cytosolic enzyme was activated to a greater extent by added PG than was the microsomal enzyme (13-14-fold versus 2-3-fold). However, after preincubation with MgATP, the cytosolic enzyme was activated to a smaller extent by added PG (3-6-fold). The inhibition of the enzyme by MgATP required a preincubation and was absent when ADP or AMP was substituted for ATP. Moreover, ATP analogues such as adenosine 5′-[beta, gamma-methylene]triphosphate and adenosine 5′-[γ-thio]triphosphate also failed to inhibit the enzyme when substituted for ATP in the preincubation. The inhibition by MgATP was not affected by including cyclic AMP in the preincubation, but Ca2+ ions alone or plus diacylglycerol in the preincubation increased the inhibition slightly. The inhibition was abolished by including an inhibitor of cyclic-AMP-dependent protein kinase in the preincubation. These observations, taken collectively, point to the inhibition of foetal pulmonary cytidylyltransferase through the phosphorylation of a protein and suggest that this key enzyme in lung surfactant production may be regulated through this mechanism.

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Chung, Y., H. Troy, A. Ramirez de Molina, I. R. Judson, P. Workman, M. O. Leach, J. C. Lacal, and J. R. Griffiths. "346 Pharmacodynamic markers for the choline kinase inhibitor MN58b in human breast cancer model by magnetic resonance spectroscopy." European Journal of Cancer Supplements 2, no. 8 (September 2004): 105. http://dx.doi.org/10.1016/s1359-6349(04)80353-7.

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Sahún-Roncero, María, Belén Rubio-Ruiz, Giorgio Saladino, Ana Conejo-García, Antonio Espinosa, Adrián Velázquez-Campoy, Francesco Luigi Gervasio, Antonio Entrena, and Ramon Hurtado-Guerrero. "The Mechanism of Allosteric Coupling in Choline Kinase α1 Revealed by the Action of a Rationally Designed Inhibitor." Angewandte Chemie International Edition 52, no. 17 (February 25, 2013): 4582–86. http://dx.doi.org/10.1002/anie.201209660.

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Sahún-Roncero, María, Belén Rubio-Ruiz, Giorgio Saladino, Ana Conejo-García, Antonio Espinosa, Adrián Velázquez-Campoy, Francesco Luigi Gervasio, Antonio Entrena, and Ramon Hurtado-Guerrero. "The Mechanism of Allosteric Coupling in Choline Kinase α1 Revealed by the Action of a Rationally Designed Inhibitor." Angewandte Chemie 125, no. 17 (February 25, 2013): 4680–84. http://dx.doi.org/10.1002/ange.201209660.

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CERBÓN, Jorge, and Rosa del Carmen LÓPEZ-SÁNCHEZ. "Diacylglycerol generated during sphingomyelin synthesis is involved in protein kinase C activation and cell proliferation in Madin-Darby canine kidney cells." Biochemical Journal 373, no. 3 (August 1, 2003): 917–24. http://dx.doi.org/10.1042/bj20021732.

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We have investigated the effects of inhibiting sphingomyelin (SM) biosynthesis on cellular diacylglycerol (DAG) content and protein kinase C (PKC) activation during growth initiation in Madin–Darby canine kidney cells. We utilized β-chloroalanine (BCA) to inactivate serine C-palmitoyltransferase, the first enzyme in the sphingolipid biosynthesis pathway. This inactivation prevented growth, but did not affect viability. When the inhibitor was replaced with fresh culture medium, the cells continued their proliferation in a normal way. BCA (2 mM) inhibited [32P]Pi, [3H]palmitic acid and [methyl-3H]choline incorporation into SM, but did not influence the synthesis of other major phospholipids. SM synthesis and DAG generation were decreased by 51% and 47.6% respectively. Particulate PKC activity was not observed in cells incubated with BCA, in contrast with a 5-fold increase in control cells. BCA inhibited 75% of the [3H]thymidine incorporation, and the cells were arrested before the S phase of the cell cycle. Moreover, exogenous d-erythrosphingosine restored SM synthesis, DAG generation and cell proliferation. These data indicate that the contribution of DAG generated during SM synthesis plays an important role in PKC activation and cell proliferation.

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Li, Wenwen, Fenfen Ma, Laiyin Zhang, Yong Huang, Xinghui Li, Aijie Zhang, Cuilan Hou, Yichun Zhu, and YiZhun Zhu. "S-Propargyl-cysteine Exerts a Novel Protective Effect on Methionine and Choline Deficient Diet-Induced Fatty Liver via Akt/Nrf2/HO-1 Pathway." Oxidative Medicine and Cellular Longevity 2016 (2016): 1–17. http://dx.doi.org/10.1155/2016/4690857.

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This study investigated the antioxidative effect of S-propargyl-cysteine (SPRC) on nonalcoholic fatty liver (NAFLD) by treating mice fed a methionine and choline deficient (MCD) diet with SPRC for four weeks. We found that SPRC significantly reduced hepatic reactive oxygen species (ROS) and methane dicarboxylic aldehyde (MDA) levels. Moreover, SPRC also increased the superoxide dismutase (SOD) activity. By Western blot, we found that this protective effect of SPRC was importantly attributed to the regulated hepatic antioxidant-related proteins, including protein kinase B (Akt), heme oxygenase-1 (HO-1), nuclear factor erythroid 2-related factor 2 (Nrf2), and cystathionineγ-lyase (CSE, an enzyme that synthesizes hydrogen sulfide). Next, we examined the detailed molecular mechanism of the SPRC protective effect using oleic acid- (OA-) induced HepG2 cells. The results showed that SPRC significantly decreased intracellular ROS and MDA levels in OA-induced HepG2 cells by upregulating the phosphorylation of Akt, the expression of HO-1 and CSE, and the translocation of Nrf2. SPRC-induced HO-1 expression and Nrf2 translocation were abolished by the phosphoinositide 3-kinase (PI3K) inhibitor LY294002. Moreover, the antioxidative effect of SPRC was abolished by CSE inhibitor DL-propargylglycine (PAG) and HO-1 siRNA. Therefore, these results proved that SPRC produced an antioxidative effect on NAFLD through the PI3K/Akt/Nrf2/HO-1 signaling pathway.

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Crilly, Karan S., Masahiro Tomono, and Zoltan Kiss. "The Choline Kinase Inhibitor Hemicholinium-3 Can Inhibit Mitogen-Induced DNA Synthesis Independent of Its Effect on Phosphocholine Formation." Archives of Biochemistry and Biophysics 352, no. 1 (April 1998): 137–43. http://dx.doi.org/10.1006/abbi.1998.0601.

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Al-saffar, N., L. E. Jackson, A. Ramirez de Molina, P. Workman, J. R. Griffiths, I. R. Judson, J. C. Lacal, and M. O. Leach. "330 Magnetic resonance spectroscopy confirms the mechanism of action of the choline kinase inhibitor MN58b in human breast cancer cells." European Journal of Cancer Supplements 2, no. 8 (September 2004): 100. http://dx.doi.org/10.1016/s1359-6349(04)80337-9.

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Mariotto, Elena, Roberta Bortolozzi, Ilaria Volpin, Davide Carta, Valentina Serafin, Benedetta Accordi, Giuseppe Basso, Pilar Luque Navarro, Luisa Carlota López-Cara, and Giampietro Viola. "EB-3D a novel choline kinase inhibitor induces deregulation of the AMPK-mTOR pathway and apoptosis in leukemia T-cells." Biochemical Pharmacology 155 (September 2018): 213–23. http://dx.doi.org/10.1016/j.bcp.2018.07.004.

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Edwards, Yasmin S., Leanne M. Sutherland, John H. T. Power, Terence E. Nicholas, and Andrew W. Murray. "Osmotic stress induces both secretion and apoptosis in rat alveolar type II cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 275, no. 4 (October 1, 1998): L670—L678. http://dx.doi.org/10.1152/ajplung.1998.275.4.l670.

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The aim of this study was to analyze the effects of osmotic shock and secretagogues such as ATP and 12- O-tetradecanoylphorbol 13-acetate (TPA) on various intracellular signaling pathways in primary cultures of alveolar type II cells and examine their potential role in regulating events such as secretion and apoptosis in these cells. Sorbitol-induced osmotic stress caused the sustained release of [3H]phosphatidylcholine ([3H]PC) from primary cultures of rat alveolar type II cells prelabeled with [3H]choline chloride. This release was not dependent on protein kinase C because downregulation of the major protein kinase C isoforms (α, βII, δ, and η) expressed in alveolar type II cells had no effect on [3H]PC secretion. Sorbitol, as well as the known secretagogues TPA and ATP, activated extracellular signal-regulated kinase. Although an inhibitor of the extracellular signal-regulated kinase cascade, PD-98059, blocked this activation, it had no effect on the release of [3H]PC. Sorbitol and ultraviolet C radiation, but not TPA or ATP, were also found to activate both p38 and stress-activated protein kinase/c-Jun NH2-terminal kinase. Furthermore, both sorbitol and ultraviolet C radiation induced apoptosis in alveolar type II cells as demonstrated by Hoechst 33258 staining of the condensed nuclei, the generation of DNA ladders, and the activation of caspases. The data indicate that multiple signaling pathways are activated by traditional secretagogues such as TPA and ATP and by cellular stresses such as osmotic shock and that these may be involved in regulating secretory and apoptotic events in alveolar type II cells.

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Wong, Mun-Teng, and Steve S. Chen. "Human Choline Kinase-α Promotes Hepatitis C Virus RNA Replication through Modulation of Membranous Viral Replication Complex Formation." Journal of Virology 90, no. 20 (August 3, 2016): 9075–95. http://dx.doi.org/10.1128/jvi.00960-16.

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ABSTRACTHepatitis C virus (HCV) infection reorganizes cellular membranes to create an active viral replication site named the membranous web (MW). The role that human choline kinase-α (hCKα) plays in HCV replication remains elusive. Here, we first showed that hCKα activity, not the CDP-choline pathway, promoted viral RNA replication. Confocal microscopy and subcellular fractionation of HCV-infected cells revealed that a small fraction of hCKα colocalized with the viral replication complex (RC) on the endoplasmic reticulum (ER) and that HCV infection increased hCKα localization to the ER. In the pTM-NS3-NS5B model, NS3-NS5B expression increased the localization of the wild-type, not the inactive D288A mutant, hCKα on the ER, and hCKα activity was required for effective trafficking of hCKα and NS5A to the ER. Coimmunoprecipitation showed that hCKα was recruited onto the viral RC presumably through its binding to NS5A domain 1 (D1). hCKα silencing or treatment with CK37, an hCKα activity inhibitor, abolished HCV-induced MW formation. In addition, hCKα depletion hindered NS5A localization on the ER, interfered with NS5A and NS5B colocalization, and mitigated NS5A-NS5B interactions but had no apparent effect on NS5A-NS4B and NS4B-NS5B interactions. Nevertheless, hCKα activity was not essential for the binding of NS5A to hCKα or NS5B. These findings demonstrate that hCKα forms a complex with NS5A and that hCKα activity enhances the targeting of the complex to the ER, where hCKα protein, not activity, mediates NS5A binding to NS5B, thereby promoting functional membranous viral RC assembly and viral RNA replication.IMPORTANCEHCV infection reorganizes the cellular membrane to create an active viral replication site named the membranous web (MW). Here, we report that human choline kinase-α (hCKα) acts as an essential host factor for HCV RNA replication. A fraction of hCKα colocalizes with the viral replication complex (RC) on the endoplasmic reticulum (ER) in HCV-infected cells. NS3-NS5B expression increases ER localization of wild-type, but not D288A mutant, hCKα, and hCKα activity facilitates the transport of itself and NS5A to the ER. Silencing or inactivation of hCKα abrogates MW formation. Moreover, hCKα is recruited by NS5A independent of hCKα activity, presumably through binding to NS5A D1. hCKα activity then mediates the ER targeting of the hCKα-NS5A complex. On the ER membrane, hCKα protein,per se, induces NS5A binding to NS5B, thereby promoting membranous RC formation and viral RNA replication. Our study may benefit the development of hCKα-targeted anti-HCV therapeutics.

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Journal articles on the topic 'Choline Kinase Inhibitor'

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