Effects Of Glycometabolism During Maturation On The Cytoplasm Of Goat Oocytes

We know that the metabolism of oocytes during maturation is very important for the resumption of oocytes and the cytoplasmic maturation.With the development of modern society, people's living standards, and the increased social pressure more and more people are suffering from diabetes and obesity problems.Because the causes of diabetes and obesity so that changes in blood sugar and thus affect the reproductive system. Many people suffering from diabetes or obesity caused changes in glucose concentration within the follicle and the changes of oocytes glucose metabolism, resulting in abnormal maturation of nuclear and cytoplasm which affects fertility. Therefore, there is an important theoretical guidance and clinical significance to study the relationship between metabolism of oocytes and maturation of nuclear and cytoplasm. Glucose is the main sources for metabolism in oocytes and it is an important role during the maturation of nuclear and cytoplasm. There are four main metabolic pathways with glucose including glycolysis, the pentose phosphate pathway (PPP), the hexosamine biosynthesis pathway (HBP) and the polyol pathway. Of which glycolysis and pentose phosphate pathway is more prominent role. Although many researchers studied the effects of the glucose in follicular on oocytes and the effects of supplementation of glucose metabolism inhibitor on the GSH in the oocytes, for the in vitro maturation of oocytes, especially in the chemical defined medium system to determine the metabolic pathways of glucose on oocyte cytoplasmic maturation and embryo development is not clear. Therefore, in this paper we respectively add inhibitor of glycolytic pathway and pentose phosphate pathway (PPP) to the chemical defined medium to study the effects of glucose metabolic pathway on the oocytes cytoplasmic maturation and embryonic development. Our results demonstrated that:1) Oocyte complexes (cumulus oocyte complexes, COCs) matured in the culture medium containing 10mM glucose get a higher morula rate and blastocyst rate than the COCs matured in the 5mM or 10mM lactate medium.2) There is a significant decrease on the embryonic development than the negative control when added the inhibitor of the pentose phosphate pathway (DHEA).The ability of embryonic development begin to decrease from the 4-cells and embryos can only develop to 8-cells.3) There is a significant decrease on the embryonic development than the negative control when added the inhibitor of glycolysis. The ability of embryonic development begin to decrease from the 2-cells and embryos can only develop to 2-cells or 4-cells when added the optimum concentration of iodoacetate. (2μM or 3μM ).4) There is a significant decrease on the concentration of GSH (reductive type) and GSX (oxidative type+ reductive type) than the negative control when added the inhibitor of pentose phosphate pathway (DHEA).5) There is a significant decrease on the content of GSX and also the ratio of the GSH/GSSG than the negative control when added the inhibitor of glycolysis.Based on above, there is a significant decrease on the embryonic development when adding either inhibitor of glycolysis or inhibitor of PPP. The decrease is more obvious when added the inhibitor of glycolysis. There is a significant decrease on the 2-cells when adding the inhibitor of glycolysis. Also,There is a significant decrease on the concentration of GSH (reductive type) and GSX (oxidative type+ reductive type) than the negative control when added the inhibitor of PPP (DHEA).This is the key factor impact the embryonic development when added the inhibitor of PPP. There is a significant decrease on the GSX and the ratio of the GSH/GSSG than the negative control when adding the inhibitor of glycolysis (iodoacetate).Of which it is maybe one of the factors that influence the embryonic development when added the inhibitor of glycolysis.We successfully use the index of embryonic development to study the effects of inhibition of glucose metabolism on the embryonic development. It will lay a theoretical foundation on the effects of embryonic development during maturation when added the inhibitor of glucose metabolism, it is also a theoretical guidance for the treatment of diabetes.