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21.
Coenzyme Q10 restores oocyte mitochondrial function and fertility during reproductive aging 下载免费PDF全文
Assaf Ben‐Meir Eliezer Burstein Aluet Borrego‐Alvarez Jasmine Chong Ellen Wong Tetyana Yavorska Taline Naranian Maggie Chi Ying Wang Yaakov Bentov Jennifer Alexis James Meriano Hoon‐Ki Sung David L. Gasser Kelle H. Moley Siegfried Hekimi Robert F. Casper Andrea Jurisicova 《Aging cell》2015,14(5):887-895
Female reproductive capacity declines dramatically in the fourth decade of life as a result of an age‐related decrease in oocyte quality and quantity. The primary causes of reproductive aging and the molecular factors responsible for decreased oocyte quality remain elusive. Here, we show that aging of the female germ line is accompanied by mitochondrial dysfunction associated with decreased oxidative phosphorylation and reduced Adenosine tri‐phosphate (ATP) level. Diminished expression of the enzymes responsible for CoQ production, Pdss2 and Coq6, was observed in oocytes of older females in both mouse and human. The age‐related decline in oocyte quality and quantity could be reversed by the administration of CoQ10. Oocyte‐specific disruption of Pdss2 recapitulated many of the mitochondrial and reproductive phenotypes observed in the old females including reduced ATP production and increased meiotic spindle abnormalities, resulting in infertility. Ovarian reserve in the oocyte‐specific Pdss2‐deficient animals was diminished, leading to premature ovarian failure which could be prevented by maternal dietary administration of CoQ10. We conclude that impaired mitochondrial performance created by suboptimal CoQ10 availability can drive age‐associated oocyte deficits causing infertility. 相似文献
22.
Nazarii Kobyliak Tetyana Falalyeyeva Petro Bodnar Tetyana Beregova 《Probiotics and antimicrobial proteins》2017,9(2):123-130
Today probiotics have been suggested as a treatment for the prevention of NAFLD. Omega-3 fatty acid supplementation may have beneficial effects in regulating hepatic lipid metabolism, adipose tissue function and inflammation. The present study was designed to determine whether probiotics plus omega-3 are superior to probiotics alone on the monosodium glutamate (MSG)-induced NAFLD model in rats. We included 60 rats divided into four groups, 15 animals in each. Rats of group I were intact. Newborn rats of groups II–IV were injected with MSG. The III (Symbiter) group received 2.5 ml/kg of multiprobiotic “Symbiter” containing concentrated biomass of 14 probiotic bacteria genera. The IV (Symbiter-Omega) groups received “Symbiter-Omega” combination of probiotic biomass supplemented with flax and wheat germ oil (250 mg of each, concentration of omega-3 fatty acids 1–5 %). In both interventional groups reduction in total NAS score was observed. Supplementation of alive probiotic mixture with omega-3 fatty acids lead to 20 % higher decrease in steatosis score (0.73 ± 0.11 vs 0.93 ± 0.22, p = 0.848) and reduction by 16.6 % of triglycerides content in liver as compared to probiotic alone. Our study demonstrated more pronounced reduction in hepatic steatosis and hepatic lipid accumulation after treatment with combination of alive probiotics and omega-3 as compared to probiotics alone. 相似文献
23.
Bibov MIu Vachaev BF Sorokina IA Lukash AI Sinichkin AA Iagovkin EA 《Prikladnaia biokhimiia i mikrobiologiia》2005,41(1):29-34
Certain carbohydrates and polyols are used at various stages of the production of immunobiological preparations as stabilizers of biological activity, particularly in the production of lactoglobulin (against opportunistic pathogens) using membrane ultrafiltration. This study concerns the effect of these substances on changes in the amide content in proteins of this lactoglobulin. Lactoglobulin was incubated in near-physiological (0.9% NaCl, pH 5.5) 10% solutions of glucose, fructose, and sorbitol at 4 and 35 degrees C for 7, 14, and 28 days. A lactoglobulin solution in 0.9% NaCl, pH 5.5, was used as the control. All substances studied suppressed the reduction of the amide group content of asparagine and, in contrast, increased the rate of amide group removal from glutamine residues in proteins of lactoglobulin preparations. 相似文献
24.
Bagnyukova TV Storey KB Lushchak VI 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2005,142(3):335-341
This study was undertaken to clarify the physiological role of catalase in the maintenance of pro/antioxidant balance in goldfish tissues by inhibiting the enzyme in vivo with 3-amino 1,2,4-triazole. Intraperitoneal injection of aminotriazole (0.5 mg/g wet mass) caused a decrease in liver catalase activity by 83% after 24 h that was sustained after 168 h post-injection. In kidney catalase activity was reduced by approximately 50% and 70% at the two time points, respectively. Levels of protein carbonyls were unchanged in liver but rose by 2-fold in kidney after 168 h. Levels of thiobarbituric acid-reactive substances were elevated in both tissues after 24 h but were reversed by 168 h. Glutathione peroxidase and glutathione-S-transferase activities increased in kidney after aminotriazole treatment whereas activities of glutathione peroxidase and glutathione reductase in liver decreased after 24 h but rebounded by 168 h. Liver glucose-6-phosphate dehydrogenase activity was reduced at both time points. Activities of these three enzymes in liver correlated inversely with the levels of lipid damage products (R2=0.65-0.81) suggesting that they may have been oxidatively inactivated. Glutathione-S-transferase activity also correlated inversely with catalase (R2=0.86). Hence, the response to catalase depletion involves compensatory changes in the activities of enzymes of glutathione metabolism. 相似文献
25.
The influence of some hydrocarbons that are often used at different stages of immunobiological preparation's production as stabilizers of biological activity on the dynamics of nonenzymatic deamidation in proteins of immune whey against conditionally pathogenic microorganisms obtained by means of membrane ultrafiltration technology is investigated. Preparations of whey were incubated in 10 per cent solutions of glucose, fructose and sorbitol at the conditions similar to physiological ones (0.9% NaCl, pH 5.5) and temperature of about +4 degrees C and +35 degrees C for 7, 14 and 28 days. A sample dissolved in 0.9% NaCl (pH 5.5) without addition of hydrocarbons was used as a "control preparate". All explored substances brought about the suppressive effect on deamidation rate of asparaginyl residues whereas that of glutaminyl residues, on the contrary, was obviously increased. The possible reasons for these observations are discussed. 相似文献
26.
Sulimenko V Dráberová E Sulimenko T Macurek L Richterová V Dráber P Dráber P 《Journal of immunology (Baltimore, Md. : 1950)》2006,176(12):7243-7253
Aggregation of the high-affinity IgE receptors (FcepsilonRIs) on the surface of granulated mast cells initiates a chain of signaling events culminating in the release of allergy mediators. Although microtubules are involved in mast cell degranulation, the molecular mechanism that controls microtubule rearrangement after FcepsilonRI triggering is poorly understood. In this study, we show that the activation of bone marrow-derived mast cells (BMMCs) induced by FcepsilonRI aggregation or treatment with pervanadate leads to a rapid polymerization of microtubules. This polymerization was not dependent on the presence of Lyn kinase as determined by experiments with BMMCs isolated from Lyn-negative mice. One of the key regulators of microtubule polymerization is gamma-tubulin. Immunoprecipitation experiments revealed that gamma-tubulin from activated cells formed complexes with Fyn and Syk protein tyrosine kinases and several tyrosine phosphorylated proteins from both wild-type and Lyn(-/-) BMMCs. Pretreatment of the cells with Src-family or Syk-family selective tyrosine kinase inhibitors, PP2 or piceatannol, respectively, inhibited the formation of microtubules and reduced the amount of tyrosine phosphorylated proteins in gamma-tubulin complexes, suggesting that Src and Syk family kinases are involved in the initial stages of microtubule formation. This notion was corroborated by pull-down experiments in which gamma-tubulin complex bounds to the recombinant Src homology 2 and Src homology 3 domains of Fyn kinase. We propose that Fyn and Syk kinases are involved in the regulation of binding properties of gamma-tubulin and/or its associated proteins, and thus modulate the microtubule nucleation in activated mast cells. 相似文献
27.
Lushchak VI Bagnyukova TV 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2006,144(3):283-289
Changes in oxygen levels occur frequently in aquatic environments; therefore, water organisms, including fishes, evolve a wide spectrum of adaptations to both anoxia/hypoxia and hyperoxia. The review describes oxidative damage to cellular constituents by reactive oxygen species, alterations in glutathione status, and response of antioxidant enzymes to variable oxygen availability in fish. Anoxia- and hypoxia-tolerant species demonstrate an anticipatory increase of some antioxidant enzymes during low-oxygen state in order to enhance their antioxidant potential for dealing with possible oxidative stress upon return to normoxia. Under hyperoxic conditions, it seems that the glutathione system plays an important adaptive role. Most stressful conditions lead to a quick increase in lipid peroxidation products that, in turn, are detoxified rapidly by respective low- and high-molecular weight antioxidants. A scheme on possible ways of regulating antioxidant enzymes by different oxygen levels is proposed. 相似文献
28.
Khomenko T Kolodney J Pinto JT McLaren GD Deng X Chen L Tolstanova G Paunovic B Krasnikov BF Hoa N Cooper AJ Szabo S 《Archives of biochemistry and biophysics》2012,525(1):60-70
Cysteamine, a coenzyme A metabolite, induces duodenal ulcers in rodents. Our recent studies showed that ulcer formation was aggravated by iron overload and diminished in iron deficiency. We hypothesized that cysteamine is selectively taken up in the duodenal mucosa, where iron absorption primarily occurs, and is transported by a carrier-mediated process. Here we report that cysteamine administration in rats leads to cysteamine accumulation in the proximal duodenum, where the highest concentration of iron in the gastrointestinal tract is found. In vitro, iron loading of intestinal epithelial cells (IEC-6) accelerated reactive oxygen species (ROS) production and increased [(14)C]cysteamine uptake. [(14)C]Cysteamine uptake by isolated gastrointestinal mucosal cells and by IEC-6 was pH-dependent and inhibited by unlabeled cysteamine. The uptake of [(14)C]cysteamine by IEC-6 was Na(+)-independent, saturable, inhibited by structural analogs, H(2)-histamine receptor antagonists, and organic cation transporter (OCT) inhibitors. OCT1 mRNA was markedly expressed in the rat duodenum and in IEC-6, and transfection of IEC-6 with OCT1 siRNA decreased OCT1 mRNA expression and inhibited [(14)C]cysteamine uptake. Cysteamine-induced duodenal ulcers were decreased in OCT1/2 knockout mice. These studies provide new insights into the mechanism of cysteamine absorption and demonstrate that intracellular iron plays a critical role in cysteamine uptake and in experimental duodenal ulcerogenesis. 相似文献
29.
Kobets T Havelková H Grekov I Volkova V Vojtíšková J Slapničková M Kurey I Sohrabi Y Svobodová M Demant P Lipoldová M 《PLoS neglected tropical diseases》2012,6(6):e1667