畜牧兽医学报2018，Vol.49Issue(5)：942-953,12.DOI:10.11843/j.issn.0366-6964.2018.05.009
黄体期不同营养水平对湖羊卵泡发育及相关葡萄糖代谢途径的影响
Effect of Different Nutrient Levels on Follicle Development and Glucose Metabolic Pathway Involved in Folliculogenesis of Hu Sheep during Luteal Phase
摘要
Abstract
This research was designed to investigate the effect of nutrient treatments during luteal phase on follicle development,apoptotic rate of ovarian cells,protein expression of glucose transporter-4 (GLUT4),and expression levels of genes involved in glucose metabolic pathway,to explore the possible mechanism involved in follicle development response to nutrients.After estrous synchronization with intravaginal progestogen sponges,estrous behavior was detected by vasectomized rams from the second day of pessary removal.The end of estrous behavior was considered to be day 0 of the estrous cycle.All 30 multiparous Hu sheep received a total mixed ration diet based on the feeding standards for maintenance requirement (M) from day 0 to day 6 of estrous cycle,and were randomly divided to 0.5M,1.5M and 1.0M groups from day 7 to day 14 of estrous cycle.Six ewes from each group were randomly selected to be slaughtered on day 15 of estrous cycle.The remaining ewes from all groups were fed the maintenance diet,and the estrous behavior was examined individually.The results indicated that the feed restriction of 0.5M significantly delayed the estrous cycle (P＜0.05),which accompanied with significantly increased and decreased ratio of small follicle (＜2.5 mm in diameter) and large follicle (≥2.5 mm in diameter) to total follicle (≥1.0 mm in diameter),respectively (P＜0.05);likewise,the apoptotic rate of ovarian tissue in 0.5M group was greater than those in 1.5M and 1.0M groups (P＜0.05;TUNEL method results).GLUT4 were immunolocalization detected in all stages of follicle development of ovarian tissue within each group,meanwhile,within ＜2.5 mm follicle,the protein expression level of GLUT4 of 1.5M group was significantly greater than that of 0.5M and 1.0M groups (P＜0.05).Analysis of expression levels of key genes involved in glucose metabolism pathway(polyol pathway,glycolysis pathway,hexosamine biosynthesis pathway (HBP),and pentose phosphate pathway (PPP) by qRT-PCR showed that,the gene expression level of glutamine:fructose-6-phosphate amidotransferase-2 (GFPT2),the enzyme which catalyzes the ratelimiting enzyme of HBP,were significantly decreased by increasing of feed intake in ＜2.5 mm follicles (P＜0.05),however,the expression levels of GFPT2 in ≥2.5 mm follicles were significantly increased by increasing of feed intake (P＜0.05).Additionally,the gene expression level of Glucose 6-phosphate dehydrogenase (G6PDH),the enzyme which catalyzes the rate determining step of the PPP,was significantly lower in ≥2.5 mm follicles of the 0.5M group than that of 1.0M and 1.5M groups (P＜0.05).Overall,the feed restriction during luteal phase prolonged estrous cycle of ewes,this response might be related to the increased of ovarian cell apoptosis rate and decrease of GLUT4 expression,but decreased HBP intensity within ＜2.5 mm follicles,and also be related to the (decreased HBP and enhanced PPP) intensity within ≥2.5 mm follicles,respectively.The current research will enrich the mechanism in follicle development regulated by different nutritional levels,by exploring the changing pattern of estrous cycle,ovarian cell apoptosis,intra-follicular glucose metabolic pathway,to provide a theoretical basis for reproductive improvement for non-pregnant ewes by feeding and management.关键词
营养水平/卵泡发育/细胞凋亡/葡萄糖转运蛋白-4/葡萄糖代谢途径/湖羊Key words
nutrient levels/follicular development/cell apoptosis/glucose transporter-4/glucose metabolic pathways/Hu sheep分类
农业科技引用本文复制引用
聂海涛,王锋,王洁,黄欣爱,刘浩,郭艺璇,王子玉,张艳丽,万永杰,樊懿萱,张国敏..黄体期不同营养水平对湖羊卵泡发育及相关葡萄糖代谢途径的影响[J].畜牧兽医学报,2018,49(5):942-953,12.基金项目
现代农业产业技术体系(CARS-38) （CARS-38）
江苏省农业三新工程(SXGC2016141) （SXGC2016141）
