Although there are many reports on the effect of glucose metabolism on oocyte nuclear maturation, there are few studies on its effect on ooplasmic maturation. By manipulating glucose metabolism pathways using a maturation medium that could support oocyte nuclear maturation but only a limited blastocyst formation without glucose, this study determined effects of glucose metabolism pathways on ooplasmic maturation. During maturation of cumulus-oocyte-complexes (COCs) with glucose, the presence of PPP inhibitor, DHEA or glycolysis inhibitor, iodoacetate significantly decreased blastocyst rates, intraoocyte glutathione and ATP. While blastocyst rates, GSH/GSSG ratio and NADPH were higher, ROS was lower significantly in COCs matured with iodoacetate than with DHEA. Fructose-6-phosphate overcame the inhibitory effect of DHEA on PPP. During maturation of COCs with pyruvate, electron transport inhibitor, rotenone or monocarboxylate transfer inhibitor, 4-CIN significantly decreased blastocyst rates. Cumulus-denuded oocytes had a limited capacity to use glucose or lactate, but they could use pyruvate to support maturation. In conclusion, whereas glycolysis promoted ooplasmic maturation mainly by supplying energy, PPP facilitated ooplasmic maturation to a greater extent by both reducing oxidative stress and supplying energy through providing fructose-6-phosphate for glycolysis. Pyruvate was transferred by monocarboxylate transporters and utilized through mitochondrial electron transport to sustain ooplasmic maturation.

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Background:Gender is one of the risk factors accounting for the high prevalence of adolescent myopia. Considerable research results have shown that myopia incidence of female is higher than that of male. This study aimed to analyze the correlation between ocular parameters and serum estrogen level and to investigate the vision changes along with estrogen change in menstrual cycle of adolescent females.Methods:A total of 120 young females aged between 15 and 16 years, diagnosed with myopia were recruited. Spherical lens, cylindrical lens, axis, interpupillary distance (IPD), and vision in each tested eye of the same subject were measured by automatic optometry and comprehensive optometry, with repetition of all measurements in the menstrual cycle of the 2nd or 3rd days, 14th days, and 28th days, respectively. Serum estradiol (E2) levels were assayed by chemiluminescence immunoassay at the same three times points of the menstrual cycle mentioned above.Results:In young females with myopia, the spherical lens showed a statistically significant difference among all different time in menstrual cycle (all P < 0.0001). The cylindrical lens, axis, and IPD were changed significantly during the menstrual cycle (P < 0.05). The vision of the three different time points in menstrual cycle had a significant difference (χ2 = 6.35, P = 0.042). The vision during the 14th and 28th day was higher compared to that on the 2nd or 3rd days (P = 0.021). Serum E2 levels were significantly different at different time points in menstrual cycle (P < 0.05). E2 levels reached its maximum value on the 14th day and the minimum value on the 2nd or 3rd day.Conclusions:In adolescent females, the spherical lens and other related ocular parameters vary sensitively with different levels of E2 in menstrual cycle. Vision in late menstrual stage is significantly higher than that in premenstrual stage.

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In previous studies on glucose metabolism during in vitro maturation, intact cumulus-oocyte complexes (COCs) were treated with enzyme inhibitors/activators. Because inhibitors/activators may have non-specificity and/or toxicity, and culture of COCs cannot differentiate whether glucose metabolism of cumulus cells (CCs) or that of the oocyte supports oocyte maturation, results from the previous studies must be verified by silencing genes in either CCs or cumulus-denuded oocytes (DOs). In this study, RNAi was adopted to specify the effects of glucose metabolism in CCs or DOs on oocyte maturation. Although silencing either glyceraldehyde 3-phosphate dehydrogenase (GAPDH) or glucose-6-phosphate dehydrogenase (G6PD) genes in CCs significantly decreased competence of the cocultured DOs, silencing G6PD impaired competence to a greater extent. While silencing G6PD or GAPDH of CCs decreased glutathione and ATP contents of cocultured DOs to similar extents, silencing G6PD increased oxidative stress as well. Analysis on metabolite contents and oxidative stress index and culture of DOs in medium conditioned with gene-silenced CCs indicated that CCs supported oocyte maturation by releasing glucose metabolites. Silencing mitochondrial pyruvate carrier 1 or NADH dehydrogenase (ubiquintone) flavoprotein 1 of DOs significantly impaired their maturation. The results have unequivocally confirmed that CCs promote oocyte maturation by releasing glucose metabolites from both pentose phosphate pathway (PPP) and glycolysis. Pyruvate is transferred into DOs by mitochondrial pyruvate carrier (MPC) and utilized through mitochondrial electron transport to support maturation.

The developmental competence of IVM porcine oocytes is still low compared with that in their in vivo counterparts. Although many studies reported effects of glucose metabolism (GM) on oocyte nuclear maturation, few reported on cytoplasmic maturation. Previous studies could not differentiate whether GM of cumulus cells (CCs) or that of cumulus-denuded oocytes (DOs) supported oocyte maturation. Furthermore, species differences in oocyte GM are largely unknown. Our aim was to address these issues by using enzyme activity inhibitors, RNAi gene silencing and special media that could support nuclear but not cytoplasmic maturation when GM was inhibited. The results showed that GM in CCs promoted pig oocyte maturation by releasing metabolites from both pentose phosphate pathway and glycolysis. Both pyruvate and lactate were transferred into pig DOs by monocarboxylate transporter and pyruvate was further delivered into mitochondria by mitochondrial pyruvate carrier in both pig DOs and CCs. In both pig DOs and CCs, pyruvate and lactate were utilized through mitochondrial electron transport and LDH-catalyzed oxidation to pyruvate, respectively. Pig and mouse DOs differed in their CC dependency for glucose, pyruvate and lactate utilization. While mouse DOs could not, pig DOs could use the lactate-derived pyruvate. In vitro maturation (IVM) can provide large numbers of competent oocytes for embryo technology studies as well as for livestock production and human clinical practice 1. It is anticipated that genetically engineered pigs will increasingly be used in biomedical research, because the pigs share many similarities with humans in terms of physiology, metabolism, genome organization, pathology and aging 2,3. However, despite great efforts to make improvements, the developmental competence of IVM porcine oocytes is still low compared with that of their counterparts in vivo and in bovine and mouse 4-6. Further observations indicated that the impaired developmental capacity of IVM oocytes were due mainly to an insufficient cytoplasmic maturation 7. The process of oocyte maturation includes both nuclear and cytoplasmic aspects 8,9. Studies have demonstrated that progression through all the dynamic processes during oocyte maturation requires a large quantity of energy from metabolism of carbohydrates, amino acids and lipids 10,11. Both meiosis resumption 12,13 and the progression of meiosis to metaphase II stage 14,15 are associated with increased glucose metabolism (GM) through one or more pathways. However, although there have been many reports on the effect of GM on oocyte nuclear maturation 16,17 , studies on GM effect on cytoplasmic maturation are limited. In the few studies reporting the GM effect on cytoplasmic maturation, the effect was analyzed together with its effect on nuclear maturation 18-20. Furthermore, in all the previous studies addressing roles of GM and its metabolites on oocyte maturation, intact cumulus-oocyte complexes (COCs) were treated with enzyme inhibitors or stimulators. Because inhibitors/stimula...

The therapeutic effect of soothing liver and regulating mind is similar for both sexes, but women were more sensitive to the efficacy of the soothing liver and regulating mind treatment compared with other methods. These findings could indicate an important issue to consider for the different acupuncture and moxibustion treatments for depression in men and women.

Background Downregulation of genes involved in lignin biosynthesis and related biochemical pathways has been used as a strategy to improve biofuel production. Plant C1 metabolism provides the methyl units used for the methylation reactions carried out by two methyltransferases in the lignin biosynthetic pathway: caffeic acid 3- O -methyltransferase (COMT) and caffeoyl-CoA 3- O -methyltransferase (CCoAOMT). Mutations in these genes resulted in lower lignin levels and altered lignin compositions. Reduced lignin levels can also be achieved by mutations in the C1 pathway gene, folylpolyglutamate synthetase1 ( FPGS1 ), in both monocotyledons and dicotyledons, indicating a link between the C1 and lignin biosynthetic pathways. To test if lignin content can be further reduced by combining genetic mutations in C1 metabolism and the lignin biosynthetic pathway, fpgs1ccoaomt1 double mutants were generated and functionally characterized. Results Double fpgs1ccoaomt1 mutants had lower thioacidolysis lignin monomer yield and acetyl bromide lignin content than the ccoaomt1 or fpgs1 mutants and the plants themselves displayed no obvious long-term negative growth phenotypes. Moreover, extracts from the double mutants had dramatically improved enzymatic polysaccharide hydrolysis efficiencies than the single mutants: 15.1% and 20.7% higher than ccoaomt1 and fpgs1 , respectively. The reduced lignin and improved sugar release of fpgs1ccoaomt1 was coupled with changes in cell-wall composition, metabolite profiles, and changes in expression of genes involved in cell-wall and lignin biosynthesis. Conclusion Our observations demonstrate that additional reduction in lignin content and improved sugar release can be achieved by simultaneous downregulation of a gene in the C1 ( FPGS1 ) and lignin biosynthetic ( CCOAOMT ) pathways. These improvements in sugar accessibility were achieved without introducing unwanted long-term plant growth and developmental defects. Electronic supplementary material The online version of this article (10.1186/s13068-019-1446-3) contains supplementary material, which is available to authorized users.