Journal articles: 'Cell lignage'

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Leroi, Armand, Scott Emmons, Ana Cunha, and Ricardo B. R. Azevedo. "The demise of the Platonic worm." Nematology 2, no. 1 (2000): 71–79. http://dx.doi.org/10.1163/156854100508917.

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AbstractNematodes are generally considered to have an adult cell number that does not vary among wildtype individuals as a consequence of invariant cell lineages (eutely). However, there is extensive evidence that at least some cell lineages can be variable in nematodes. In a comparative study of 13 free-living nematode species, we have shown that the adult epidermis of most species contained variable numbers of nuclei and that this variance was positively correlated with mean epidermal nuclear number. Here we present simulations of the lateral seam cell lineages of four species and show that variance in cell number is influenced by lineage topology, as well as by the frequency of lineage variants. We show that the epidermal variability of Panagrellus redivivus cannot be accounted for by the complexity of its lineage, but requires higher levels of lineage variability than are found in Caenorhabditis elegans, Oscheius myriophila and Rhabditella octopleura. Our findings suggest that many nematodes may have tissues composed of indeterminate numbers of cells formed from variable lineages and, as such, resemble other metazoans. Les nématodes sont généralement considérés comme ayant un nombre de cellules invariable chez les individus de type sauvage, conséquence d’un lignage cellulaire fixe (eutélie). Cependant, il est d’évidence qu’au moins certains des lignages cellulaires peuvent varier chez les nématodes. Dans une étude comparative portant sur 13 espèces de nématodes libres, nous avions montré que l’épiderme de la plupart de ces espèces comportait un nombre variable de noyaux et que cette variabilité était corrélée positivement avec le nombre de noyaux épidermiques. Nous présentons ici des simulations des lignages cellulaires de la suture latérale de quatre espèces et démontrons que le nombre de cellules est influencé tant par la topologie du lignage que par la fréquence des variants de ce lignage. Nous montrons que la variabilité de l’épiderme de Panagrellus redivivus ne peut être mise au compte de la complexité de son lignage, mais demande des niveaux élevés de variabilité de ce lignage, tels ceux trouvés chez Caenorhabditis elegans, Oscheius myriophila et Rhabditella octopleura. Nos observations suggèrent que nombre de nématodes possèdent des tissus composés d’un nombre indéterminé de cellules dérivant de lignages variables et, de ce fait, ressemblent aux autres metazoaires.

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Monties, Bernard. "Composition chimique des bois de chêne: composés phénoliques, relations avec quelques propriétés physiques et chimiques susceptibles d'influencer la qualité des vins et des eaux-de-vie." OENO One 21, no. 3 (1987): 169. http://dx.doi.org/10.20870/oeno-one.1987.21.3.1282.

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Les polyphénols du bois de chêne, extractibles et composés liés à la paroi végétale = lignines, lignanes, tanins et aldéhydes phénoliques, ont été envisagés au niveau moléculaire de leurs relations avec les propriétés physico-chimiques des bois : retrait, porosité, propriétés mécaniques.Des résultats originaux ont été aussi présentés concernant le fractionnement des polyphénols pariétaux, l'incrustation des parois par les tanins hydrolysables: acide ellagique associé à des fractions de lignine, ainsi que la formation d'aldéhydes phénoliques (vanilline, syringaldéhyde, aldéhydes coniférylique et sinapylique) par pyrolyse douce de la lignine. Des mécanismes réactionnels hypothétiques ont été suggérés.+++Oak wood phenolics, extractives and cell wall linked compounds : lignins, lignans, tanins and phenolic aldehydes have been discussed, at the molecular level, in their relations with physico-chemical properties of wood = shrinking, permeability and mechanical properties.Unpublished results have been also reported concerning fractionnation of cell wall phenolics, incrustation of cell wall by tanins: ellagic acid associated with lignins fractions and formation of phenolic aldehydes (vanillin, syringaldehyde, coniferaldehyde, sinapaldehyde) during mild pyrolysis of lignin in oak wood. Hypotherical reaction mechanism have been suggested.

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Huh, Jungmoo, Chang-Min Lee, Seoyoung Lee, Soeun Kim, Namki Cho, and Young-Chang Cho. "Comprehensive Characterization of Lignans from Forsythia viridissima by UHPLC-ESI-QTOF-MS, and Their NO Inhibitory Effects on RAW 264.7 Cells." Molecules 24, no. 14 (2019): 2649. http://dx.doi.org/10.3390/molecules24142649.

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Lignans are known to be an important class of phenylpropanoid secondary metabolites. In the course of our studies on the chemodiversity of lignans, the necessity arose to develop a method for the fast detection and identification of bioactive lignan subclasses. In this study, we detected 10 lignan derivatives of different extracts of F. viridissima by UHPLC-ESI-QTOF-MS. Lignan glycosides (1 and 2), lignans (3 and 4), and lignan dimers (5–10) were identified by analysis of their exact masses and MSe spectra along with the characteristic mass fragmentation patterns and molecular formulas. We further investigated NO inhibitory effects of F. viridissima fractions and their major lignan derivatives to evaluate those anti-inflammatory effects. The methylene chloride fraction of F. viridissima as well as compounds 8 and 10 showed potent dose-dependent NO inhibitory effects on RAW 264.7 cells. Corresponding to the NO inhibition by compounds 8 and 10, lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) expression was notably reduced by both compounds. Our combined data with the bioactive results and the component analysis by UHPLC-ESI-QTOF-MS suggest that the methylene chloride fraction of F. viridissima roots could be potential anti-inflammatory agents and these are related to major lignans including dimeric dibenzylbutyrolactone lignans.

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Mulabagala, Vanisree, Gottumukkala V. Subbaraju, Modukuri V. Ramani, David L. DeWitt, and Muraleedharan G. Nair. "Lipid Peroxidation, Cyclooxygenase Enzyme and Tumor Cell Proliferation Inhibitory Lignans from Justicia Species." Natural Product Communications 3, no. 11 (2008): 1934578X0800301. http://dx.doi.org/10.1177/1934578x0800301109.

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The genus Justicia is a rich source of lignans, especially aryl naphthalide lignans. Lignans are biologically active phytochemicals, and are reported to possess antiplatelet, antiviral, anti-tumor, antidepressant, and insect antifeedant activities. In the present study, we report lipid peroxidation (LPO), cyclooxygenase (COX-1 and −2) enzyme and tumor cell proliferation inhibitory activities of lignans, namely, lariciresinol (1), isolariciresinol (2), neesiinoside A (3), justirumalin (4), justalakonin (5), justicidin G (6), sesamin (7), sesamolin (8), jusmicranthin methyl ether (9), taiwanin E methyl ether (10), lignan J1 (11), jusneesiinol (12), jusmicranthin ethyl ether (13), tiruneesiin (14), justicidin E (15) and simplexolin (16). Lignans 1 and 2 were isolated from J. tranquebariensis, 3, 4, 6, 9, 10, 11, 12, 13 and 14 from J. neesii Ramamoorthy, 5 from J. purpurea and 7, 8, 15 and 16 from J. orbiculata. Among the lignans assayed, 1, 2, 12 and 14 showed 79.6, 86.2, 90.8 and 95.9% and 3 41.3% inhibition of LPO at 25 μg/mL. The lignans 4, 9 and 16 inhibited COX-2 enzyme by 67.2, 73.0 and 72.8%, respectively, when tested at 25 μg/mL. Similarly, lignans 3, 4, 10, 11 and 15 inhibited COX-1 enzyme by 59.9, 89.2, 69.6, 73.9, and 80.1%, respectively, at 25 μg/mL. When assayed at 25 μg/mL, 4 inhibited human stomach and breast cancer cell lines by 42.8 and 42.1%, respectively. Also, at 25 μg/mL the lignan 7 inhibited the growth of CNS, lung and breast cancer cell lines by 50.0, 41.3, and 42.0 %, respectively, and 15 inhibited the proliferation of lung, breast and colon cell lines by 40–53%.

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Mansikkala, Tuomas, Minna Patanen, Anna Kärkönen, et al. "Lignans in Knotwood of Norway Spruce: Localisation with Soft X-ray Microscopy and Scanning Transmission Electron Microscopy with Energy Dispersive X-ray Spectroscopy." Molecules 25, no. 13 (2020): 2997. http://dx.doi.org/10.3390/molecules25132997.

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Lignans are bioactive compounds that are especially abundant in the Norway spruce (Picea abies L. Karst.) knotwood. By combining a variety of chromatographic, spectroscopic and imaging techniques, we were able to quantify, qualify and localise the easily extractable lignans in the xylem tissue. The knotwood samples contained 15 different lignans according to the gas chromatography-mass spectrometry analysis. They comprised 16% of the knotwood dry weight and 82% of the acetone extract. The main lignans were found to be hydroxymatairesinols HMR1 and HMR2. Cryosectioned and resin-embedded ultrathin sections of the knotwood were analysed with scanning transmission X-ray microscopy (STXM). Cryosectioning was found to retain only lignan residues inside the cell lumina. In the resin-embedded samples, lignan was interpreted to be unevenly distributed inside the cell lumina, and partially confined in deposits which were either readily present in the lumina or formed when OsO4 used in staining reacted with the lignans. Furthermore, the multi-technique characterisation enabled us to obtain information on the chemical composition of the structural components of knotwood. A simple spectral analysis of the STXM data gave consistent results with the gas chromatographic methods about the relative amounts of cell wall components (lignin and polysaccharides). The STXM analysis also indicated that a torus of a bordered pit contained aromatic compounds, possibly lignin.

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Mason, Julie K., and Lilian U. Thompson. "Flaxseed and its lignan and oil components: can they play a role in reducing the risk of and improving the treatment of breast cancer?" Applied Physiology, Nutrition, and Metabolism 39, no. 6 (2014): 663–78. http://dx.doi.org/10.1139/apnm-2013-0420.

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Flaxseed (FS), rich in the phytoestrogen lignans and α-linolenic acid-rich oil, has been suggested to have an anticancer effect. Questions remain whether FS and its lignan and oil components are effective in reducing breast cancer risk and tumour growth, and can interact beneficially with breast cancer drugs. To find answers, in vitro, animal, observational, and clinical studies on FS and its lignan and oil components were reviewed. The majority of studies in various rodent models show that 2.5%–10% FS diet or the equivalent amount of lignan or oil reduces tumour growth. Ten percent FS and equivalent lignans do not interfere with but rather increase the effectiveness of tamoxifen (80 mg/day) while the 4% FS oil increases trastuzumab/Herceptin (2.5 mg/kg) effectiveness. Observational studies show that FS and lignan intake, urinary excretion, or serum levels are associated with reduced risk, particularly in postmenopausal women. Lignans reduce breast cancer and all-cause mortality by 33%–70% and 40%–53%, respectively, without reducing tamoxifen effectiveness. Clinical trials show that FS (25 g/day with 50 mg lignans; 32 days) reduces tumour growth in breast cancer patients and lignans (50 mg/day; 1 year) reduces risk in premenopausal women. Mechanisms include decreased cell proliferation and angiogenesis and increased apoptosis through modulation of estrogen metabolism and estrogen receptor and growth factor receptor signalling pathways. More clinical trials are needed but current overall evidence indicates that FS and its components are effective in the risk reduction and treatment of breast cancer and safe for consumption by breast cancer patients.

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Xu, Xuan, Cédric Guignard, Jenny Renaut, et al. "Insights into Lignan Composition and Biosynthesis in Stinging Nettle (Urtica dioica L.)." Molecules 24, no. 21 (2019): 3863. http://dx.doi.org/10.3390/molecules24213863.

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Stinging nettle (Urtica dioica L.) has been used as herbal medicine to treat various ailments since ancient times. The biological activity of nettle is chiefly attributed to a large group of phenylpropanoid dimers, namely lignans. Despite the pharmacological importance of nettle lignans, there are no studies addressing lignan biosynthesis in this plant. We herein identified 14 genes encoding dirigent proteins (UdDIRs) and 3 pinoresinol-lariciresinol reductase genes (UdPLRs) in nettle, which are two gene families known to be associated with lignan biosynthesis. Expression profiling of these genes on different organs/tissues revealed a specific expression pattern. Particularly, UdDIR7, 12 and 13 displayed a remarkable high expression in the top internode, fibre tissues of bottom internodes and roots, respectively. The relatively high expression of UdPLR1 and UdPLR2 in the young internodes, core tissue of bottom internode and roots is consistent with the high accumulation of lariciresinol and secoisolariciresinol in these tissues. Lignan quantification showed a high abundance of pinoresinol in roots and pinoresinol diglucosides in young internodes and leaves. This study sheds light on lignan composition and biosynthesis in nettle, providing a good basis for further functional analysis of DIRs and PLRs and, ultimately, engineering lignan metabolism in planta and in cell cultures.

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Bylund, Annika, Niina Saarinen, Jie-xian Zhang, et al. "Anticancer Effects of a Plant Lignan 7-Hydroxymatairesinol on a Prostate Cancer Model In Vivo." Experimental Biology and Medicine 230, no. 3 (2005): 217–23. http://dx.doi.org/10.1177/153537020523000308.

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Clinical intervention studies and experimental studies with lignan-rich diets suggest that lignans may have inhibitory effects on prostate cancer, but no clinical or experimental studies with purified lignans have been published. The purpose of this study was to investigate the effect of a plant lignan 7-hydroxymatairesinol (HMR) on LNCaP human prostate cancer xenografts in athymic mice. Athymic nude male mice were injected subcutaneously with LNCaP cells. Starting 3 days after tumor cell injections, a control diet or a control diet supplemented with 0.15% or 0.30% of HMR was administered to mice and the tumor take rate and growth was observed for 9 weeks. HMR diet inhibited the growth of LNCaP tumors. Mice treated with HMR had smaller tumor volume, lower tumor take rate, increased proportion of nongrowing tumors, and higher tumor cell apoptotic index compared with controls. Furthermore, the cell proliferation index was reduced in mice receiving the 0.30% HMR diet compared with mice receiving the control diet. Our results suggest that dietary HMR started at the early phase of the tumor development inhibits the growth of the LNCaP human prostate cancer xenografts in athymic male mice.

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Aimaiti, Simayijiang, Yohei Saito, Shuichi Fukuyoshi, et al. "Isolation, Structure Elucidation, and Antiproliferative Activity of Butanolides and Lignan Glycosides from the Fruit of Hernandia nymphaeifolia." Molecules 24, no. 21 (2019): 4005. http://dx.doi.org/10.3390/molecules24214005.

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Seven new butanolides, peltanolides A–G (1–7), and two lignan glucosides, peltasides A (8) and B (9), along with eleven known compounds, 10–20, were isolated from a crude CH3OH/CH2Cl2 (1:1) extract of the fruit of Hernandia nymphaeifolia (Hernandiaceae). The structures of 1–9 were characterized by extensive 1D and 2D NMR spectroscopic and HRMS analysis. The absolute configurations of newly isolated compounds 1–9 were determined from data obtained by optical rotation and electronic circular dichroism (ECD) exciton chirality methods. Butanolides and lignan glucosides have not been isolated previously from this genus. Several isolated compounds were evaluated for antiproliferative activity against human tumor cell lines. Lignans 15 and 16 were slightly active against chemosensitive tumor cell lines A549 and MCF-7, respectively. Furthermore, both compounds displayed significant activity (IC50 = 5 µM) against a P-glycoprotein overexpressing multidrug-resistant tumor cell line (KB-VIN) but were less active against its parent chemosensitive cell line (KB).

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Basini, Giuseppina, Carmela Spatafora, Corrado Tringali, Simona Bussolati, and Francesca Grasselli. "Effects of a Ferulate-Derived Dihydrobenzofuran Neolignan on Angiogenesis, Steroidogenesis, and Redox Status in a Swine Cell Model." Journal of Biomolecular Screening 19, no. 9 (2014): 1282–89. http://dx.doi.org/10.1177/1087057114536226.

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In the ongoing search for new therapeutic compounds, lignans and neolignans, which are widely distributed in plants, deserve special attention because of their interactions with several biological targets. Searching for potential antiangiogenic agents related to natural lignans/neolignans, we were attracted by a previously studied synthetic dihydrobenzofuran neolignan. We synthesized the compound by means of an eco-friendly, enzyme-mediated biomimetic coupling of the methyl ester of ferulic acid, and the present study was aimed to deeply investigate its effect in angiogenesis bioassays validated in our laboratory. In addition, a previously well-defined granulosa cell model was employed to evaluate the effect of dihydrobenzofuran neolignan on cell viability, steroidogenesis, and redox status. Present data support the antiangiogenic effect of this neolignan. Moreover, we demonstrate that, at least at the highest concentrations tested, dihydrobenzofuran neolignan affects granulosa cell viability and steroidogenesis. In addition, the compound inhibits generation of free radicals and stimulates scavenger enzyme activities. The present data, which are a further deepening of the evaluation of the biological activities of the dihydrobenzofuran lignan in well-defined cell models, are of interest and worthy of special attention.

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Mistrzak, Paulina, Hanna Celejewska-Marciniak, Wojciech J. Szypuła, Olga Olszowska, and Anna K. Kiss. "Identification and quantitative determination of pinoresinol in Taxus ×media Rehder needles, cell suspension and shoot cultures." Acta Societatis Botanicorum Poloniae 84, no. 1 (2015): 125–32. http://dx.doi.org/10.5586/asbp.2014.038.

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The aim of our study was to investigate the presence and quantitative contents of lignans in the tissues of Taxus ×media. The presence of the lignans: pinoresinol, matairesinol and secoisolariciresinol was assessed in needles, shoots cultures and suspension culture. Pinoresinol was the only lignan found in the tissue of T. ×media. The total pinoresinol content in the needles and in the shoots was 1.24 mg/g dry weight (dw) and 0.69 mg/g dw, respectively. Most of the pinoresinol identified was appeared glycosidically bound. In needles, the amount of glycosidically bound pinoresinol (0.81 mg/g dw) was about twice as high as that of free pinoresinol (0.43 mg/g dw). The content of free and glycosidically bound pinoresinol showed the level of 0.18 mg/g dw and 0.51 mg/g dw, respectively in the in vitro shoot cultures. In the cell culture, no pinoresinol was found.

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Erdemoglu, Nurgun, Bilge Sener, and M. Iqbal Choudhary. "Bioactivity of Lignans from Taxus baccata." Zeitschrift für Naturforschung C 59, no. 7-8 (2004): 494–98. http://dx.doi.org/10.1515/znc-2004-7-807.

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AbstractThree lignan derivatives, (-)-taxiresinol (1), (-)-3′-demethylisolariciresinol-9′-hydroxyisopropylether (2) and (-)-3-demethylisolariciresinol (3), previously isolated from the heartwood of Taxus baccata L. (Taxaceae) were investigated for cytotoxicity against the Oncology Cell Line Panel (breast, colon, ovary, prostate, lung and a normal adult bovine aortic endothelial cell line) as well as for antimicrobial activities. Besides, a chloroform-soluble portion of the ethanol extract from the heartwood of T. baccata was also tested for antimicrobial activities. Compounds 1 - 3 did not demonstrate much cytotoxic potency according to the reference drug etoposide. With the exception of compound 2, the other two lignans (1 and 3) and the chloroform extract were shown to possess antifungal activity, whereas only the chloroform extract exhibited antibacterial activity against Pseudomonas aeruginosa

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Sasheva, Pavlina, and Iliana Ionkova. "USE OF METHYL JASMONATE TO ENHANCE THE PRODUCTION OF 6-METHOXYPODOPHYLLOTOXIN IN CELL CULTURES OF LINUM THRACICUM SSP. THRACICUM." CBU International Conference Proceedings 3 (September 19, 2015): 437–43. http://dx.doi.org/10.12955/cbup.v3.635.

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Secondary metabolites, such as lignans have important ecological role for plants and at the same time are lead structures for drug design in human medicine. The aryltetralin type of lignans are strong cytotoxic agents and are found in members of the genus Linum (Linaceae).Objective: In vitro cultures of Linum thracicum ssp. thracicum were developed to identify a medium type and an elicitation technique that favor enhanced production of the aryltetralin lignan 6-methoxypodophyllotoxin.Method: Methyl jasmonate and salicylic acid were administered to four cell lines of Linum thracicum ssp. thracicum for 24 and 72 hours. The 6-methoxypodophyllotoxin was identified by HPLS-ESI-MS/MS in positive ion mode, and its production was determined via quantitative HPLC analysis.Results: A cell line, called Li-20, which was developed in reduced sucrose environment proved to be the fastest growing and the highest producing among the tested cell lines. Within 24 hours upon MJ elicitation, the eight-day-old Li-20 increased 2.3-fold in 6-methoxypodophyllotoxin content, reaching 4.3 mg on a dry weight basis. Negative or no effect was registered after salicylic acid application.Conclusion: MJ elicitation is an effective strategy to improve the 6-methoxypodophyllotoxin accumulation within short periods of time, and an optimization of the cultivation medium beforehand is a prerequisite in the pipeline.

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Ko, Young Hyun, Miran Jeong, Dae Sik Jang, and Jung-Hye Choi. "Gomisin L1, a Lignan Isolated from Schisandra Berries, Induces Apoptosis by Regulating NADPH Oxidase in Human Ovarian Cancer Cells." Life 11, no. 8 (2021): 858. http://dx.doi.org/10.3390/life11080858.

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The fruits of Schisandra chinensis (Schisandra berries) are used as health food supplements and popular food ingredients in East Asia. Lignans, major and characteristic polyphenol compounds of Schisandra berries, possess various biological activities, including hepatoprotective and anticancer effects. However, the biological activities of gomisin L1, a lignan isolated from Schisandra berries, are less to be investigated. In this study, the antitumor activity of gomisin L1 and its underlying molecular mechanism in human ovarian cancer cells were investigated. Gomisin L1 exhibited potent cytotoxic activity against A2780 and SKOV3 ovarian cancer cells. Flow cytometry analysis revealed that the growth inhibitory effects of gomisin L1 were mediated by the induction of apoptosis. Furthermore, gomisin L1 induced an increase in intracellular reactive oxygen species (ROS) levels, and the antioxidant N-acetyl cysteine significantly negated gomisin L1-induced cell death. Moreover, inhibition of NADPH oxidase (NOX) using an inhibitor and siRNA attenuated gomisin L1-induced death of, and ROS production in, human ovarian cancer cells. Taken together, these data indicate that the lignan gomisin L1 from Schisandra berries induces apoptotic cell death by regulating intracellular ROS production via NOX.

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Han, Jianxin, Xiaoyu Chen, Wei Liu, Hao Cui, and Tao Yuan. "Triterpenoid Saponin and Lignan Glycosides from the Traditional Medicine Elaeagnus angustifolia Flowers and Their Cytotoxic Activities." Molecules 25, no. 3 (2020): 462. http://dx.doi.org/10.3390/molecules25030462.

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A new triterpenoid saponin, named terpengustifol A (1), and two new lignan glucosides, phengustifols A and B (2 and 3), were isolated from the flowers of Elaeagnus angustifolia. Their structures were determined by the extensive analysis of the spectroscopic data (including NMR and HRMS) and ECD calculations. Compound 1 possesses an unusual monoterpene (Z)-6-hydroxy-2,6-dimethylocta-2,7-dienoyl unit at C-21. Compounds 2 and 3 are a pair of diastereoisomers, while their aglycones are a pair of enantiomers. Compounds 1 and 2 exhibited moderate cytotoxic activities against A375 cell lines with IC50 values at 12.1 and 15.6 μM, respectively. This is firstly reported the triterpenoid saponin and lignans isolated from the Elaeagnus angustifolia flowers.

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Martins, Júlia, Joana Coelho, Maraine Catarina Tadini, et al. "Yangambin and Epi-yangambin Isomers: New Purification Method from Ocotea fasciculata and First Cytotoxic Aspects Focusing on In Vivo Safety." Planta Medica 86, no. 06 (2020): 415–24. http://dx.doi.org/10.1055/a-1118-3828.

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Abstract Ocotea fasciculata presents yangambin (YAN) and its isomer epi-yangambin (EPI-YAN) as major lignans, which are employed as the plant markers for quality control purposes and as potential pharmacological compounds. However, a gap between the pure isomers and safety and efficacy protocols is faced by the scientific community. In this context, this work aimed to report (i) a new and advantageous purifying process in a semi-preparative scale for YAN and EPI-YAN isolation from Ocotea fasciculata, and (ii) an in vitro cytotoxicity study to estimate, for the first time, the LD50 values of the isolated epimers, as well as the influence of albumin concentration in cell culture medium. The best condition for epimers isolation was achieved in normal-phase liquid chromatography. The lignan fraction (LF), previously obtained from the plant ethanolic extract, was purified yielding 17% and 29% of YAN and EPI-YAN, respectively. The in vitro study demonstrated that YAN and EPI-YAN were safe, and only at the highest concentration studied, a decrease on cell viability was observed. The estimated LD50 value was higher than 1612 mg/kg for both epimers. The LF, on the other hand, demonstrated an estimated LD50 of 422 mg/kg. Lignan cytotoxicity studies also evidenced that the higher cell viability was related to the higher concentration of fetal bovine serum as a source of albumin in medium. This is the first time the LD50 and safety of the isolated epimers were estimated, opening up great perspectives of success in in vivo studies.

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Sharma, Mayuri, Kritika Dadhwal, Yogesh Gat, et al. "A review on newer techniques in extraction of oleaginous flaxseed constituents." OCL 26 (2019): 14. http://dx.doi.org/10.1051/ocl/2019006.

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Flaxseed is the chief oilseed crop that is grown in many regions of the world for medicinal and nutritional purposes. It has been used for oil and fiber since centuries. Flaxseed has an enormous role in functional foods for its nutritional and pharmaceutical values. Among the various components of flaxseed lignans, phenolic acids, proteins and oil are of the main interest. Oil and lignans have prime concentrations in the flaxseed. To study the extraction of these compounds, various extraction methods have been investigated. Oil has been extracted by mechanical pressing in ancient times but presently new techniques have been developed. These include microwave assisted extraction, supercritical CO2 extraction, ultrasonic assisted extraction, etc. Enzymes are also gaining importance in the extraction of oil, lignan and proteins as they give more yield of compounds and easily degrade the cell wall of the flaxseed. The need of these novel techniques lies in the fact that traditional methods have different shortcomings like low yield, more time, more energy and less environmental friendly. This review put on a view to different techniques which have been investigated for the extraction of different components of flaxseed. Quality evaluation and comparison of flaxseed oils and other bioactive components obtained by newer techniques with those produced by conventional extraction methods is also reported.

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Boluda, Carlos J., Juan M. Trujillo, José A. Pérez, Hermelo López, Zulma Aragón, and Raquel G. Díaz. "Semisynthesis of Justicidone and a 1,2-Quinone Lignan. Cytotoxic Activity of Some Natural and Synthetic Lignans." Natural Product Communications 4, no. 2 (2009): 1934578X0900400. http://dx.doi.org/10.1177/1934578x0900400214.

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The dioxo-lignans of the arylnaphthalene-type named justicidone (2) and elenodione (3) were obtained from elenoside (1) through a short and efficient semisynthetic process. Justicidone (2), one of its synthetic precursors, 4-(benzo[d][1,3]dioxol-5-yl)-5,6,8-trimethoxy-3a,4-dihydronaphtho[2,3-c]furan-1(3H)-one (9), and the aglycone of elenoside (5) showed cytotoxic activity towards the HL-60 cell line (IC50 = 7.25 μM, 5.41 μM and 2.06 μM, respectively).

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Liu, Ban, Chao-Peng Li, Wen-Qi Wang, Shu-Guang Song, and Xiu-Ming Liu. "Lignans Extracted from Eucommia Ulmoides Oliv. Protects Against AGEs-Induced Retinal Endothelial Cell Injury." Cellular Physiology and Biochemistry 39, no. 5 (2016): 2044–54. http://dx.doi.org/10.1159/000447900.

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Background/Aims: Advanced glycation end products (AGEs) could elicit oxidative stress, trigger and aggravate endothelium damage in several ischemic retinopathies including diabetic retinopathy (DR). The leaves of Eucommia ulmoides O., also referred to as Tu-chung or Du-zhong, have been used for the treatment of hypertension and diabetes, showing great antioxidant activity and anti-glycation activity. Lignans is one of the main bioactive components of Eucommia ulmoides. This study mainly investigated the effect of lignans treatment on AGEs-induced endothelium damage. Methods: MTT assay, Hoechst staining, and calcein-AM/ propidium iodide (PI) staining was conducted to determine the effect of lignans treatment on endothelial cell function in vitro. Retinal trypsin digestion, Evans blue assay, isolectin staining, and western blots were conducted to determine the effect of lignans treatment on retinal microvascular function in vivo. Western blot, protein immunoprecipitation (IP), MTT assays, and enzyme activity assay was conducted to detect the effect of ligans treatment on oxidative stress response. Results: Lignans protected retinal endothelial cell against AGEs-induced injury in vitro and diabetes-induced vascular dysfunction in vivo. Lignans treatment could regulate oxidative stress response in retinal endothelial cell line, retina, and liver. Moreover, we showed that NRF2/HO-1 signaling was critical for lignans-mediated oxidative stress regulation. Conclusion: Lignans treatment could protect against endothelial dysfunction in vivo and in vitro via regulating Nrf2/HO-1 signaling. Lignans might be developed as a promising drug for the treatment of diabetes-induced microvascular dysfunction.

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Davidson, Samuel J., Lisa I. Pilkington, Nina C. Dempsey-Hibbert, et al. "Modular Synthesis and Biological Investigation of 5-Hydroxymethyl Dibenzyl Butyrolactones and Related Lignans." Molecules 23, no. 12 (2018): 3057. http://dx.doi.org/10.3390/molecules23123057.

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Dibenzyl butyrolactone lignans are well known for their excellent biological properties, particularly for their notable anti-proliferative activities. Herein we report a novel, efficient, convergent synthesis of dibenzyl butyrolactone lignans utilizing the acyl-Claisen rearrangement to stereoselectively prepare a key intermediate. The reported synthetic route enables the modification of these lignans to give rise to 5-hydroxymethyl derivatives of these lignans. The biological activities of these analogues were assessed, with derivatives showing an excellent cytotoxic profile which resulted in programmed cell death of Jurkat T-leukemia cells with less than 2% of the incubated cells entering a necrotic cell death pathway.

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Glitsø, L. V., W. M. Mazur, H. Adlercreutz, et al. "Intestinal metabolism of rye lignans in pigs." British Journal of Nutrition 84, no. 4 (2000): 429–37. http://dx.doi.org/10.1017/s0007114500001732.

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To study the intestinal metabolism of lignans, the concentrations of plant and mammalian lignans in intestinal digesta sampled along the intestinal tract of pigs were determined by isotope dilution GC–MS. The pigs were fed rye-bread diets made from either whole rye-grains or rye-grain milling fractions enriched in pericarp–testa, aleurone or endosperm cells. The content and characteristics of dietary fibre varied between diets and had been shown to induce different colon fermentation patterns. As the metabolism of lignans depends on the action of the intestinal flora, we tested whether the rye-bread diets influence the metabolism of lignans. In the ileum, the lignans were mainly present as conjugated plant lignans, which were determined only when the analytical procedure included a hydrolysis step. High recovery of dietary lignans in the ileum may indicate that the lignans enter the enterohepatic circulation. In addition, two to three times the intake of lignans were recovered in the faeces when the diets had a high content of dietary fibre suggesting underestimation of plant lignans in the diet. Most of the plant lignans disappeared from the intestinal tract between the terminal ileum and the caecum. The intestinal concentrations and the disappearance of lignans correlated with the content of lignans in the diet, being highest on the pericarp–testa diet and lowest on the endosperm diet. No effect of fermentation pattern on the intestinal metabolism of lignans was observed. The lignans were liberated from the pericarp–testa diet although the plant cell walls remained largely undegraded.

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Elmaidomy, Abeer H., Rabab Mohammed, Hossam M. Hassan, et al. "Metabolomic Profiling and Cytotoxic Tetrahydrofurofuran Lignans Investigations from Premna odorata Blanco." Metabolites 9, no. 10 (2019): 223. http://dx.doi.org/10.3390/metabo9100223.

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Metabolomic profiling of different Premna odorata Blanco (Lamiaceae) organs, bark, wood, young stems, flowers, and fruits dereplicated 20, 20, 10, 20, and 20 compounds, respectively, using LC–HRESIMS. The identified metabolites (1–34) belonged to different chemical classes, including iridoids, flavones, phenyl ethanoids, and lignans. A phytochemical investigation of P. odorata bark afforded one new tetrahydrofurofuran lignan, 4β-hydroxyasarinin 35, along with fourteen known compounds. The structure of the new compound was confirmed using extensive 1D and 2D NMR, and HRESIMS analyses. A cytotoxic investigation of compounds 35–38 against the HL-60, HT-29, and MCF-7 cancer cell lines, using the MTT assay showed that compound 35 had cytotoxic effects against HL-60 and MCF-7 with IC50 values of 2.7 and 4.2 µg/mL, respectively. A pharmacophore map of compounds 35 showed two hydrogen bond acceptor (HBA) aligning the phenoxy oxygen atoms of benzodioxole moieties, two aromatic ring features vectored on the two phenyl rings, one hydrogen bond donor (HBD) feature aligning the central hydroxyl group and thirteen exclusion spheres which limit the boundaries of sterically inaccessible regions of the target’s active site.

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Xia, Yamu, Yuanyuan Zhang, Wei Wang, Yining Ding, and Rui He. "Synthesis and bioactivity of erythro-nordihydroguaiaretic acid, threo-(-)-saururenin and their analogues." Journal of the Serbian Chemical Society 75, no. 10 (2010): 1325–35. http://dx.doi.org/10.2298/jsc090410108x.

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Full details of the total syntheses of erythro-nordihydroguaiaretic acid, threo-(-)-saururenin and their analogues are presented. The syntheses were based on a unified synthetic strategy involving the Stobbe Reaction, alkylation to construct the skeleton of lignans and resolution of the threo- and erythro-isomers. The syntheses were achieved in eight to nine steps from simple aromatic precursors, and by this route 13 lignans were obtained. Among the synthesized lignans, seven lignans were natural products; moreover three of the seven natural products were synthesized for the first time. The effect of 13 lignans was examined on HIV Tat transactivation in human epithelial cells, HSV-1 gene and human leukemic, liver, prostate, stomach and breast cancer cell. Bioactivity results indicated that one product showed activity against the HIV gene and five compounds exhibited anti-HSV activity.

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Suthiwong, Jittra, Kampeebhorn Boonloh, Veerapol Kukongviriyapan, and Chavi Yenjai. "Cytotoxicity against Cholangiocarcinoma and HepG2 Cell Lines of Lignans from Hernandia nymphaeifolia." Natural Product Communications 13, no. 1 (2018): 1934578X1801300. http://dx.doi.org/10.1177/1934578x1801300118.

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Eleven lignans (1-11) were isolated from the seed of Hernandia nymphaeifolia. Most of the lignans exhibited strong to moderate cytotoxicity against cholangiocarcinoma KKU-M156 and HepG2 cell lines. Compounds 4 and 8 showed cytotoxicity against the KKU-M156 cell line with IC50 values of 5.2 μ M (Emax 96%) and 5.4 (Emax 59%) μM, respectively. In the cases of cytotoxicity against the HepG2 cell line, compounds 2, 3, 4, and 8 showed cytotoxicity with IC50 values of 1.7 M (Emax 84%), 4.1 μM (Emax 74%), 4.5 μM (Emax 68%), and 5.2 μM (Emax 78%), respectively.

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Okunishi, Tomoya, Naohiro Takaku, Patcharawadee Wattanawikkit, et al. "Lignan production inDaphne odora cell cultures." Journal of Wood Science 48, no. 3 (2002): 237–41. http://dx.doi.org/10.1007/bf00771374.

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Rahman, M., P. M. Dewick, D. E. Jackson, and J. A. Lucas. "LIGNANS IN FORSYTHIA LEAVES AND CELL CULTURES." Journal of Pharmacy and Pharmacology 38, S12 (1986): 15P. http://dx.doi.org/10.1111/j.2042-7158.1986.tb14244.x.

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Nabeta, Kensuke, Megumi Hirata, Yuriko Ohki, S. W. Ananda Samaraweera, and Hiroshi Okuyama. "Lignans in cell cultures of Picea glehnii." Phytochemistry 37, no. 2 (1994): 409–13. http://dx.doi.org/10.1016/0031-9422(94)85069-0.

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Shin, Hyeji, Yoo Kyong Han, Youngjoo Byun, Young Ho Jeon, and Ki Yong Lee. "Lignans from Machilus thunbergii as Thymic Stromal Lymphopoietin Inhibitors." Molecules 26, no. 16 (2021): 4804. http://dx.doi.org/10.3390/molecules26164804.

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Thymic stromal lymphopoietin (TSLP) plays an important role in the pathophysiology of various allergic diseases that are mediated by T helper cell type-2 (Th2) responses, including asthma and atopic dermatitis. The primary focus of this study was the identification of potent inhibitors of the TSLP signaling pathway for potential therapeutic use. The 80% methanol extract of Machilus thunbergii bark significantly inhibited the signal transducer and activator of transcription 5 (STAT5) phosphorylation in human mast cell (HMC)-1 cells. Through activity-guided isolation, three lignans (1–3) were obtained and identified as (+)-galbelgin (1), meso-dihydroguaiaretic acid (2), and machilin A (3). Among them, two lignans (1 and 2) significantly inhibited STAT5 phosphorylation and TSLP/TSLPR interaction, as determined by ELISA. Our results indicated that lignans isolated from M. thunbergii are a promising resource for the treatment of allergic diseases.

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Mohagheghzadeh, Abdolali, Shadab Dehshahri, and Shiva Hemmati. "Accumulation of Lignans by in vitro Cultures of Three Linum Species." Zeitschrift für Naturforschung C 64, no. 1-2 (2009): 73–76. http://dx.doi.org/10.1515/znc-2009-1-213.

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Justicidin B, an arylnaphthalene lignan, has strong cytotoxicity on chronic myeloid and chronic lymphoid leukemia cell lines. The first report of the production of justicidin B in a Linum species concerned in vitro culture of Linum austriacum. Therefore, culture characterization and presence of arylnaphthalene-type lignans in calli and plantlets of Linum tenuifolium from section Linastrum, Linum bienne, and Linum glaucum from section Linum were studied. Seed germination of L. tenuifolium in the light and darkness was significantly higher (p < 0.05) than of L. bienne in the light and L. glaucum in the darkness. L. tenuifolium seedling length in the darkness was significantly higher (p < 0.01) than under light conditions. There were no significant differences in the calli and shoot biomass weight, number and length of shoots in three species over one month, while the shoot diameter of L. bienne was significantly different (p < 0.05) from that of L. glaucum. Justicidin B was detected in L. glaucum callus and plantlet cultures by HPLC/MS/UV-DAD and HPLC coupled with a photodiode array detector. This finding is important from pharmaceutical point of view and shows the chemosystematic relation between L. glaucum and L. austriacum and this method will be a powerful tool for detecting natural products in interested and endangered medicinal plants.

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Bohnenstengel, Frank I., Klaus G. Steube, Corinna Meyer, Hilmar Quentmeier, Bambang W. Nugroho, and Peter Proksch. "1H-Cyclopenta[b]benzofuran Lignans from Aglaia Species Inhibit Cell Proliferation and Alter Cell Cycle Distribution in Human Monocytic Leukemia Cell Lines." Zeitschrift für Naturforschung C 54, no. 12 (1999): 1075–83. http://dx.doi.org/10.1515/znc-1999-1212.

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Thirteen naturally occurring 1H-cyclopenta[b]benzofuran lignans of the rocaglamide type as well as one naturally occurring aglain congener all of them isolated from three Aglaia species (Aglaia duperreana, A. oligophylla and A. spectabilis) collected in Vietnam were studied for their antiproliferative effects using the human monocytic leukemia cell lines MONO-MAC-1 and MONO-MAC-6. Only rocaglamide type compounds showed significant inhibition of [3H-]thymidine incorporation and the most active compound didesmethylrocaglamide inhibited cell growth in a similar concentration range as the well-known anticancer drug vinblastine sulfate. Detailed structure-activity analysis indicated that the OH-group at C-8b which is a common structural feature of most naturally occurring rocaglamide compounds is essential for the described antiproliferative activity since replacement of this group by methylation led to a complete loss of the inhibitory activity for the resulting derivative. Rocaglamide derivatives rapidly inhibited DNA as well as protein biosynthesis of MONOMAC- 6 cells at concentrations well below those of actinomycin D or cycloheximide which were used as positive controls in the respective experiments. Didesmethylrocaglamide was furthermore able to induce growth arrest of MONO-MAC-1 cells in the G2/M and probably G0/Gl-phase of the cell cycle with no morphological indication of cellular damage. Our data suggests that 1H-cyclopenta[b]benzofuran lignans of the rocaglamide type act primarily by a cytostatic mechanism.

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Wasik, Kaja, James Gurtowski, Xin Zhou, et al. "Genome and transcriptome of the regeneration-competent flatworm, Macrostomum lignano." Proceedings of the National Academy of Sciences 112, no. 40 (2015): 12462–67. http://dx.doi.org/10.1073/pnas.1516718112.

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The free-living flatworm, Macrostomum lignano has an impressive regenerative capacity. Following injury, it can regenerate almost an entirely new organism because of the presence of an abundant somatic stem cell population, the neoblasts. This set of unique properties makes many flatworms attractive organisms for studying the evolution of pathways involved in tissue self-renewal, cell-fate specification, and regeneration. The use of these organisms as models, however, is hampered by the lack of a well-assembled and annotated genome sequences, fundamental to modern genetic and molecular studies. Here we report the genomic sequence of M. lignano and an accompanying characterization of its transcriptome. The genome structure of M. lignano is remarkably complex, with ∼75% of its sequence being comprised of simple repeats and transposon sequences. This has made high-quality assembly from Illumina reads alone impossible (N50 = 222 bp). We therefore generated 130× coverage by long sequencing reads from the Pacific Biosciences platform to create a substantially improved assembly with an N50 of 64 Kbp. We complemented the reference genome with an assembled and annotated transcriptome, and used both of these datasets in combination to probe gene-expression patterns during regeneration, examining pathways important to stem cell function.

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Barahouie, Haniyeh. "Entre bande dessinée et jeu vidéo: Le Secret de la Licorne d’Hergé." ALTERNATIVE FRANCOPHONE 2, no. 7 (2020): 55–65. http://dx.doi.org/10.29173/af29401.

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À un cadre d’analyse qui prendrait en compte une analyse des produits dérivés liés aux Aventures de Tintin, l’autrice préfère prendre en compte la transmédialité de l’œuvre, au moins depuis la sortie du film et du jeu vidéo Les aventures de Tintin : Le secret de la Licorne. Il s’agit d’un cas de transmédialité avec œuvre-source et certains enjeux propres à l’adaptation sont pris en compte, d’autant que l’adaptation d’œuvres canoniques comme celle-ci a tendance à prendre en considération un certain niveau de fidélité à cause des attentes du public. Ainsi, le jeu vidéo, dans la lignée du film de Spielberg, propose une ligne claire adaptée. Par ailleurs, le jeu, conçu dans la plus grande partie de ces modules comme une plateforme de défilement horizontal, n’est pas sans rappeler l’horizontalité des bandes dans les pages des Aventures de Tintin. Enfin, l’autrice montre comment l’utilisation des cinématiques dans le jeu vidéo permet notamment de situer le jeu dans le contexte d’une franchise transmédiale.

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Nimeth, K. "CELL RENEWAL AND APOPTOSIS IN MACROSTOMUM SP. [LIGNANO]." Cell Biology International 26, no. 9 (2002): 801–15. http://dx.doi.org/10.1016/s1065-6995(02)90950-9.

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Rahman, Maiada M. A., Paul M. Dewick, David E. Jackson, and John A. Lucas. "Production of lignans in Forsythia intermedia cell cultures." Phytochemistry 29, no. 6 (1990): 1861–66. http://dx.doi.org/10.1016/0031-9422(90)85029-f.

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de Andrade-Neto, Valter F., Tito da Silva, Lucia M. Xavier Lopes, Virgílio E. do Rosário, Fernando de Pilla Varotti, and Antoniana U. Krettli. "Antiplasmodial Activity of Aryltetralone Lignans from Holostylis reniformis." Antimicrobial Agents and Chemotherapy 51, no. 7 (2007): 2346–50. http://dx.doi.org/10.1128/aac.01344-06.

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ABSTRACT Extracts from Holostylis reniformis were tested in vivo against Plasmodium berghei and in vitro against a chloroquine-resistant strain of Plasmodium falciparum. The hexane extract of the roots was the most active, causing 67% reduction of parasitemia in vivo. From this extract, six lignans, including a new (7′R,8S,8′S)-3′,4′-methylenedioxy-4,5-dimethoxy-2,7′-cyclolignan-7-one, were isolated and tested in vitro against P. falciparum. The three most active lignans showed 50% inhibitor concentrations of ≤0.32 μM. An evaluation of minimum lethal dose (30%) values showed low toxicity for these lignans in a hepatic cell line (Hep G2A16). Therefore, these compounds are potential candidates for the development of antimalarial drugs.

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Liu, Yongbei, Yupei Yang, Shumaila Tasneem, et al. "Lignans from Tujia Ethnomedicine Heilaohu: Chemical Characterization and Evaluation of Their Cytotoxicity and Antioxidant Activities." Molecules 23, no. 9 (2018): 2147. http://dx.doi.org/10.3390/molecules23092147.

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Heilaohu, the roots of Kadsura coccinea, has a long history of use in Tujia ethnomedicine for the treatment of rheumatoid arthritis and gastroenteric disorders, and a lot of work has been done in order to know the material basis of its pharmacological activities. The chemical investigation led to the isolation and characterization of three new (1–3) and twenty known (4–23) lignans. Three new heilaohulignans A-C (1–3) and seventeen known (4–20) lignans possessed dibenzocyclooctadiene skeletons. Similarly, one was a diarylbutane (21) and two were spirobenzofuranoid dibenzocyclooctadiene (22–23) lignans. Among the known compounds, 4–5, 7, 13–15 and 17–22 were isolated from this species for the first time. The structures were established, using IR, UV, MS and NMR data. The absolute configurations of the new compounds were determined by circular dichroism (CD) spectra. The isolated lignans were further evaluated for their cytotoxicity and antioxidant activities. Compound 3 demonstrated strong cytotoxic activity with an IC50 value of 9.92 µM, compounds 9 and 13 revealed weak cytotoxicity with IC50 values of 21.72 µM and 18.72 µM, respectively in the HepG-2 human liver cancer cell line. Compound 3 also showed weak cytotoxicity against the BGC-823 human gastric cancer cell line and the HCT-116 human colon cancer cell line with IC50 values of 16.75 µM and 16.59 µM, respectively. A chemiluminescence assay for antioxidant status of isolated compounds implied compounds 11 and 20, which showed weak activity with IC50 values of 25.56 µM and 21.20 µM, respectively.

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Ditchev, Ivaylo, and Anne-Hélène Kerbiriou. "Des passions nationales virtualisées." Anthropologie et Sociétés 40, no. 1 (2016): 71–84. http://dx.doi.org/10.7202/1036371ar.

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L’état d’esprit que l’on appelle « nationalisme » paraît de nos jours tenir davantage d’une communauté de fans que d’une quelconque doctrine politique. Cela est vrai en particulier pour les générations les plus jeunes qui socialisent en ligne et qui ont grandi dans un monde fluide de désinstitutionalisation globale. À partir d’exemples de nationalisme en ligne en Bulgarie, recueillis ces dernières années par le biais d’une analyse des médias suivie dans certains cas d’entrevues en ligne et en personne, j’avance que la nouvelle constellation médiatique a en grande partie accentué cette évolution. De façon plus générale, celle-ci est liée au virage culturel qui a transformé la culture, la faisant passer d’une façon d’être à une façon de posséder.

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Peter Kutney, James, James P. Kutney, Yung Ping Chen, et al. "Studies with Plant Cell Culture of Podophyllum peltatum L. II. Biotransformation of Dibenzylbutanolides to Lignans. Development of a "Biological Factory" for Lignan Synthesis." HETEROCYCLES 36, no. 1 (1993): 13. http://dx.doi.org/10.3987/com-92-6177.

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Simanov, Daniil, Imre Mellaart-Straver, Irina Sormacheva, and Eugene Berezikov. "The FlatwormMacrostomum lignanoIs a Powerful Model Organism for Ion Channel and Stem Cell Research." Stem Cells International 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/167265.

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Bioelectrical signals generated by ion channels play crucial roles in many cellular processes in both excitable and nonexcitable cells. Some ion channels are directly implemented in chemical signaling pathways, the others are involved in regulation of cytoplasmic or vesicular ion concentrations, pH, cell volume, and membrane potentials. Together with ion transporters and gap junction complexes, ion channels form steady-state voltage gradients across the cell membranes in nonexcitable cells. These membrane potentials are involved in regulation of such processes as migration guidance, cell proliferation, and body axis patterning during development and regeneration. While the importance of membrane potential in stem cell maintenance, proliferation, and differentiation is evident, the mechanisms of this bioelectric control of stem cell activity are still not well understood, and the role of specific ion channels in these processes remains unclear. Here we introduce the flatwormMacrostomum lignanoas a versatile model organism for addressing these topics. We discuss biological and experimental properties ofM. lignano, provide an overview of the recently developed experimental tools for this animal model, and demonstrate how manipulation of membrane potential influences regeneration inM. lignano.

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Goels, Thomas, Elisabeth Eichenauer, Julia Langeder, et al. "Norway Spruce Balm: Phytochemical Composition and Ability to Enhance Re-epithelialization In Vitro." Planta Medica 86, no. 15 (2020): 1080–88. http://dx.doi.org/10.1055/a-1141-0921.

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AbstractThe balm of the Norway spruce (Picea abies) is a well-known traditional herbal medicine used to cure wounds. Even though clinical trials have confirmed its empirical use, the active constituents, their mode of action, and the exact composition of this natural product are still unknown. In this study, the balm was subjected to fractionated extraction and further purified employing flash chromatography, HPLC-PDA-ELSD, preparative and analytical TLC. Hydroxycinnamic acids ( 1– 3), the lignan pinoresinol ( 4), four hydroxylated derivatives of dehydroabietic acid (DHAA) ( 5 – 8), and dehydroabietic acid ( 9) were isolated. Their structures were elucidated by LC-MS, 1D- and 2D-NMR. Four extracts, two commercially available resin acids–pimaric acid ( 10) and isopimaric acid ( 11)–and the isolated compounds were tested for increased re-epithelialization of cell-free areas in a human adult low calcium high temperature keratinocytes monolayer. Lysophosphatidic acid (10 µM) served as positive control and ranged between 100% and 150% rise in cell-covered area related to the vehicle control. Two extracts containing carboxylic acids and non-acidic apolar constituents, respectively, boosted wound closure by 47% and 36% at 10 and 3 µg/mL, respectively. Pinoresinol, DHAA, three of its hydroxylated derivatives, and pimaric and isopimaric acid as well as defined combinations of the hydroxylated DHAA derivatives led to a significantly enhanced wound closure by up to 90% at concentrations between 1 and 10 µM. Overall, lignans and diterpene resin acids, main constituents of Norway spruce balm, are able to increase migration or proliferation of keratinocytes in vitro. The presented data link the phytochemistry of this natural wound healing agent with boosted re-epithelialization.

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Sasheva, Pavlina, Iliana Ionkova, and Nadezhda Stoilova. "Methyl Jasmonate Induces Enhanced Podophyllotoxin Production in Cell Cultures of Thracian Flax (Linum thracicum ssp. thracicum)." Natural Product Communications 10, no. 7 (2015): 1934578X1501000. http://dx.doi.org/10.1177/1934578x1501000722.

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The Linum thracicum ssp. thracicum cell lines developed in this study are a feasible source for the sustainable production of podophyllotoxin, a lignan with an aryltetralin skeleton that is used for the manufacture of the chemotherapeutic drugs etopophos and teniposide. We used mass spectrometry to confirm the presence of the aryltetralin lignan in the thracian flax cell cultures. Next, we explored how changes in the culture medium influenced the podophyllotoxin content. Out of six developed cell lines, four were selected for further experiments and challenged with elicitors. The selected cell lines clustered into two groups: developed in full strength medium (Li) vs developed in half strength medium (HS). While podophyllotoxin production in the Li cell lines was boosted by 80% upon administration of the elicitor methyl jasmonate, the HS lines produced high amounts of the target metabolite triggered by reduced concentration of nutrients and were only slightly influenced by the elicitor.

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Fuss, Elisabeth. "Lignans in plant cell and organ cultures: An overview." Phytochemistry Reviews 2, no. 3 (2003): 307–20. http://dx.doi.org/10.1023/b:phyt.0000045500.56476.f5.

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Petersen, Maike, and A. Wilhelm Alfermann. "The production of cytotoxic lignans by plant cell cultures." Applied Microbiology and Biotechnology 55, no. 2 (2001): 135–42. http://dx.doi.org/10.1007/s002530000510.

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Antúnez-Mojica, Mayra, Andrés Rojas-Sepúlveda, Mario Mendieta-Serrano, et al. "Lignans from Bursera fagaroides Affect In Vivo Cell Behavior by Disturbing the Tubulin Cytoskeleton in Zebrafish Embryos." Molecules 24, no. 1 (2018): 8. http://dx.doi.org/10.3390/molecules24010008.

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By using a zebrafish embryo model to guide the chromatographic fractionation of antimitotic secondary metabolites, seven podophyllotoxin-type lignans were isolated from a hydroalcoholic extract obtained from the steam bark of Bursera fagaroides. The compounds were identified as podophyllotoxin (1), β-peltatin-A-methylether (2), 5′-desmethoxy-β-peltatin-A-methylether (3), desmethoxy-yatein (4), desoxypodophyllotoxin (5), burseranin (6), and acetyl podophyllotoxin (7). The biological effects on mitosis, cell migration, and microtubule cytoskeleton remodeling of lignans 1–7 were further evaluated in zebrafish embryos by whole-mount immunolocalization of the mitotic marker phospho-histone H3 and by a tubulin antibody. We found that lignans 1, 2, 4, and 7 induced mitotic arrest, delayed cell migration, and disrupted the microtubule cytoskeleton in zebrafish embryos. Furthermore, microtubule cytoskeleton destabilization was observed also in PC3 cells, except for 7. Therefore, these results demonstrate that the cytotoxic activity of 1, 2, and 4 is mediated by their microtubule-destabilizing activity. In general, the in vivo and in vitro models here used displayed equivalent mitotic effects, which allows us to conclude that the zebrafish model can be a fast and cheap in vivo model that can be used to identify antimitotic natural products through bioassay-guided fractionation.

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Labbé, Stéphane. "La médiation du livre à l’ère du numérique : l’enjeu des algorithmes de recommandation." Documentation et bibliothèques 61, no. 1 (2015): 15–21. http://dx.doi.org/10.7202/1029000ar.

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Par la réalisation d’une réflexion théorique, nous avons analysé la médiation en ligne du livre à l’aide des algorithmes de recommandation. Nous avons adopté une approche communicationnelle, celle-ci portant un regard sur le processus même de la médiation. Nous avons tenté de circonscrire le concept d’algorithme de recommandation et décrit son fonctionnement. Cela nous a permis d’identifier les enjeux centraux que soulève le recours aux algorithmes de recommandation dans le processus de médiation en ligne du livre, c’est-à-dire l’enjeu de la diversité culturelle et celui du cloisonnement des individus dans des identités et des communautés numériques.

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Hsieh, TJ, CH Chen, WL Lo, and CY Chen. "Lignans from the Stem of Cinnamomum camphora." Natural Product Communications 1, no. 1 (2006): 1934578X0600100. http://dx.doi.org/10.1177/1934578x0600100104.

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(+)-Diasesamin (1), (+)-sesamin (2), (+)-episesamin, stearic acid, palmitic acid, a mixture of β-sitosterol and stigmasterol, and a mixture of β-sitosterol-D-glucoside and stigmasterol-D-glucoside were isolated from the stems of Cinnamomum camphora (L.) Presl.. Among these compounds, 1 is obtained for the first time from a natural source. The cytotoxicity of 2 on Hep G2 and HeLa cell cancer lines was also investigated. The flow cytometric assay results indicated that 2 elicited a decrease in the percentage of the S phase of the cell cycle in Hep G2 cells after incubation for 24 h. These results reflect that 2 inhibited the DNA synthetic event in Hep G2 cells.

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Majumder, Anrini. "Influence of an Indirect Precursor on Podophyllotoxin Accumulation in Cell Suspension Cultures of Podophyllum hexandrum." Plant Tissue Culture and Biotechnology 22, no. 2 (2013): 171–77. http://dx.doi.org/10.3329/ptcb.v22i2.14207.

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Podophyllum hexandrum is an endangered, commercial source of a naturally occurring lignan podophyllotoxin, which is a precursor of potent anticancer drugs. Cell suspension cultures were established using four-year-old cell line RC4 of P. hexandrum in liquid P1 medium [half strength B5 basal medium supplemented with 1% (w/v) sucrose, 2,4-D (1 mg/l), GA3 (1 mg/l) and BA (0.1 mg/l)]. The effect of different concentrations (100, 250 and 500 mg/l) of tryptophan, an indirect precursor of lignan biosynthesis, was studied on cell suspension cultures. Cultures accumulated 2.7 times more podophyllotoxin than untreated control cultures when treated with 250 mg/l tryptophan. Biomass yield was, however not improved following the addition of tryptophan. DOI: http://dx.doi.org/10.3329/ptcb.v22i2.14207 Plant Tissue Cult. & Biotech. 22(2): 171-177, 2012 (December)

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Mohagheghzadeh, Abdolali, Azra Gholami, Shiva Hemmati, Mohammad Reza Shams Ardakani, Thomas J. Schmidt, and A. Wilhelm Alfermann. "Root Cultures of Linum Species Section Syllinum as Rich Sources of 6-Methoxypodophyllotoxin." Zeitschrift für Naturforschung C 62, no. 1-2 (2007): 43–49. http://dx.doi.org/10.1515/znc-2007-1-208.

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Linum spp. from section Syllinum are promising for the production of aryltetralin lignans like podophyllotoxin (PTOX) and 6-methoxypodophyllotoxin (MPTOX). MPTOX is a PTOX congener that has cytotoxic activity comparable with PTOX. In this study root cultures of Linum Bungei from section Dasyllinum, L. strictum from section Linastrum, L. album, L. mucronatum ssp. mucronatum and L. nodiflorum from section Syllinum were established and their MPTOX levels were investigated in 1000 ml flasks. Root cultures of L. mucronatum ssp. mucronatum and L. nodiflorum were used to examine cell growth and production of MPTOX during a culture period of 36 days in 250 ml flasks. Considerable amounts of MPTOX in root cultures (1000 ml flasks) of L. album (6 mg/100 g DW), L. mucronatum ssp. mucronatum (770 mg/100 g DW) and L. nodiflorum (91 mg/100 g DW) were detected while it wasn’t detected in root cultures of L. Bungei and L. strictum. In time course experiments, the maximum amount of MPTOX in L. nodiflorum root culture was at day 16 with 480 mg/ 100 g DW and the maximum amount of MPTOX in L. mucronatum ssp. mucronatum root culture was at day 12 with 130 mg/100 g DW. The results showed that root cultures of Linum species from section Syllinum are rich sources of MPTOX and since this lignan has remarkable cytotoxic activity, it can be used as a precursor for the production of antitumor agents.

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Arroo, R. R. J., A. W. Alfermann, M. Medarde, M. Petersen, N. Pras, and J. G. Woolley. "Plant cell factories as a source for anti-cancer lignans." Phytochemistry Reviews 1, no. 1 (2002): 27–35. http://dx.doi.org/10.1023/a:1015824000904.

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Elfahmi, Sieb Batterman, Albert Koulman, et al. "Lignans from Cell Suspension Cultures ofPhyllanthusniruri, an Indonesian Medicinal Plant." Journal of Natural Products 69, no. 1 (2006): 55–58. http://dx.doi.org/10.1021/np050288b.

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Journal articles on the topic 'Cell lignage'

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