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951.
Celastrol reverses palmitic acid (PA)‐caused TLR4‐MD2 activation‐dependent insulin resistance via disrupting MD2‐related cellular binding to PA
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![点击此处可从《Journal of cellular physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
952.
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954.
Different fermentation strategies by Schizochytrium mangrovei strain pq6 to produce feedstock for exploitation of squalene and omega‐3 fatty acids
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![点击此处可从《Journal of phycology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Thom Thi Le Thi Huong Quynh Hoang Van Nhat Pham Minh Hien Thi Hoang Hoai Thu Thi Ngo Dang Diem Hong 《Journal of phycology》2018,54(4):550-556
Schizochytrium mangrovei strain PQ 6 was investigated for coproduction of docosahexaenoic acid (C22: 6ω‐3, DHA ) and squalene using a 30‐L bioreactor with a working volume of 15 L under various batch and fed‐batch fermentation process regimes. The fed‐batch process was a more efficient cultivation strategy for achieving higher biomass production rich in DHA and squalene. The final biomass, total lipid, unsaponifiable lipid content, and DHA productivity were 105.25 g · L?1, 43.40% of dry cell weight, 8.58% total lipid, and 61.66 mg · g?1 · L?1, respectively, after a 96 h fed‐batch fermentation. The squalene content was highest at 48 h after feeding glucose (98.07 mg · g?1 of lipid). Differences in lipid accumulation during fermentation were correlated with changes in ultrastructure using transmission electron microscopy and Nile Red staining of cells. The results may be of relevance to industrial‐scale coproduction of DHA and squalene in heterotrophic marine microalgae such as Schizochytrium . 相似文献
955.
We herein report the design, synthesis and molecular docking studies of 2,4-thiazolidinedione derivatives containing benzene sulphonyl group which are docked against the Peroxisome Proliferator Activated Receptor (PPARγ) target. Compound 7p was most effective in lowering the blood glucose level as compared to standard drugs pioglitazone and rosiglitazone. Compound 7p exhibited potent PPAR-γ transactivation of 61.2% with 1.9 folds increase in gene expression. In molecular docking studies 7p showed excellent interactions with amino acids TYR 473, SER 289, HIE 449, TYR 327, ARG 288, MET 329 and LEU 228. Compound 7p did not cause any damage to the liver without any noteworthy weight gain and may be considered as promising candidates for the development of new antidiabetic agents. 相似文献
956.
Histone acetyltransferase general control non‐repressed protein 5 (GCN5) affects the fatty acid composition of Arabidopsis thaliana seeds by acetylating fatty acid desaturase3 (FAD3)
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![点击此处可从《The Plant journal : for cell and molecular biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Xinye Liu Zhenshan Liu Yingyin Yao Zhaorong Hu Huiru Peng Mingming Xin Dao‐Xiu Zhou Yirong Zhang Zhongfu Ni 《The Plant journal : for cell and molecular biology》2016,88(5):794-808
Seed oils are important natural resources used in the processing and preparation of food. Histone modifications represent key epigenetic mechanisms that regulate gene expression, plant growth and development. However, histone modification events during fatty acid (FA) biosynthesis are not well understood. Here, we demonstrate that a mutation of the histone acetyltransferase GCN5 can decrease the ratio of α‐linolenic acid (ALA) to linoleic acid (LA) in seed oil. Using RNA‐Seq and ChIP assays, we identified FAD3, LACS2, LPP3 and PLAIIIβ as the targets of GCN5. Notably, the GCN5‐dependent H3K9/14 acetylation of FAD3 determined the expression levels of FAD3 in Arabidopsis thaliana seeds, and the ratio of ALA/LA in the gcn5 mutant was rescued to the wild‐type levels through the overexpression of FAD3. The results of this study indicated that GCN5 modulated FA biosynthesis by affecting the acetylation levels of FAD3. We provide evidence that histone acetylation is involved in FA biosynthesis in Arabidopsis seeds and might contribute to the optimization of the nutritional structure of edible oils through epigenetic engineering. 相似文献
957.
Differential Gene Expression and Protein Localization of Cryptosporidium parvum Fatty Acyl‐CoA Synthetase Isoforms
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![点击此处可从《The Journal of eukaryotic microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Fengguang Guo Haili Zhang Harold Ross Payne Guan Zhu 《The Journal of eukaryotic microbiology》2016,63(2):233-246
Cryptosporidium parvum is unable to synthesize fatty acids de novo, but possesses three long‐chain fatty acyl‐CoA synthetase (CpACS) isoforms for activating fatty acids. We have recently shown that these enzymes could be targeted to kill the parasite in vitro and in vivo. Here, we demonstrated that the CpACS genes were differentially expressed during the parasite life cycle, and their proteins were localized to different subcellular structures by immunofluorescence and immuno‐electron microscopies. Among them, CpACS1 displayed as an apical protein in sporozoites and merozoites, but no or little presence during the intracellular merogony until the release of merozoites, suggesting that CpACS1 probably functioned mainly during the parasite invasion and/or early stage of intracellular development. Both CpACS2 and CpACS3 proteins were present in all parasite life cycle stages, in which CpACS2 was present in the parasite and the parasitophorous vacuole membranes (PVM), whereas CpACS3 was mainly present in the parasite plasma membranes with little presence in the PVM. These observations suggest that CpACS2 and CpACS3 may participate in scavenging and transport of fatty acids across the PVM and the parasite cytoplasmic membranes, respectively. 相似文献
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959.
G. Maulucci O. Cohen B. Daniel A. Sansone P. I. Petropoulou S. Filou 《Free radical research》2016,50(10):S40-S50
AbstractMetabolic homeostasis of fatty acids is complex and well-regulated in all organisms. The biosynthesis of saturated fatty acids (SFA) in mammals provides substrates for β-oxidation and ATP production. Monounsaturated fatty acids (MUFA) are products of desaturases that introduce a methylene group in cis geometry in SFA. Polyunsaturated fatty acids (n-6 and n-3 PUFA) are products of elongation and desaturation of the essential linoleic acid and α-linolenic acid, respectively. The liver processes dietary fatty acids and exports them in lipoproteins for distribution and storage in peripheral tissues. The three types of fatty acids are integrated in membrane phospholipids and determine their biophysical properties and functions. This study was aimed at investigating effects of fatty acids on membrane biophysical properties under varying nutritional and pathological conditions, by integrating lipidomic analysis of membrane phospholipids with functional two-photon microscopy (fTPM) of cellular membranes. This approach was applied to two case studies: first, pancreatic beta-cells, to investigate hormetic and detrimental effects of lipids. Second, red blood cells extracted from a genetic mouse model defective in lipoproteins, to understand the role of lipids in hepatic diseases and metabolic syndrome and their effect on circulating cells. 相似文献
960.
Obesity is known to be a poorer prognosis factor for breast cancer in postmenopausal women. Among the diverse endocrine factors associated to obesity, leptin has received special attention since it promotes breast cancer cell growth and invasiveness, processes which force cells to adapt their metabolism to satisfy the increased demands of energy and biosynthetic intermediates. Taking this into account, our aim was to explore the effects of leptin in the metabolism of MCF-7 breast cancer cells. Polarographic analysis revealed that leptin increased oxygen consumption rate and cellular ATP levels were more dependent on mitochondrial oxidative metabolism in leptin-treated cells compared to the more glycolytic control cells. Experiments with selective inhibitors of glycolysis (2-DG), fatty acid oxidation (etomoxir) or aminoacid deprivation showed that ATP levels were more reliant on fatty acid oxidation. In agreement, levels of key proteins involved in lipid catabolism (FAT/CD36, CPT1, PPARα) and phosphorylation of the energy sensor AMPK were increased by leptin. Regarding glucose, cellular uptake was not affected by leptin, but lactate release was deeply repressed. Analysis of pyruvate dehydrogenase (PDH), lactate dehydrogenase (LDH) and pyruvate carboxylase (PC) together with the pentose-phosphate pathway enzyme glucose-6 phoshate dehydrogenase (G6PDH) revealed that leptin favors the use of glucose for biosynthesis. These results point towards a role of leptin in metabolic reprogramming, consisting of an enhanced use of glucose for biosynthesis and lipids for energy production. This metabolic adaptations induced by leptin may provide benefits for MCF-7 growth and give support to the reverse Warburg effect described in breast cancer. 相似文献