左旋肉碱对猪卵母细胞体外成熟、脂肪代谢和孤雌胚胎发育的影响

Effects of L-carnitine on oocytes in vitro maturation,lipid metabolism and parthenogenetic embryos development in porcine

【目的】探讨不同质量浓度的左旋肉碱对猪卵母细胞体外成熟、脂肪代谢和孤雌胚胎发育的影响.【方法】在成熟培养液中添加不同质量浓度左旋肉碱,观察其对猪卵母细胞体外成熟和孤雌胚胎发育的影响,并利用油红染色、三酰甘油定量试剂盒和定量RT-PCR技术检测其对卵母细胞脂肪代谢及其关键水解酶表达水平的影响.【结果和结论】在成熟液中添加100 ng/mL左旋肉碱能极显著促进猪卵母细胞的脂肪滴代谢(P<0.001),并显著提高猪卵母细胞体外成熟率和孤雌激活囊胚发育率(P<0.05);在胚胎培养液中添加100 ng/mL左旋肉碱能够显著提高猪孤雌胚胎卵裂率(P<0.05),其囊胚率和囊胚质量均有提高的趋势;通过定量RT-PCR进一步发现100 ng/mL左旋肉碱极显著降低猪卵母细胞中激素敏感脂肪酶基因(HSL,P<0.01)和三酰甘油水解酶基因(ATGL,P<0.001)的mRNA表达水平,表明左旋肉碱能够影响调控脂肪代谢关键酶基因的表达.试验结果表明,左旋肉碱具有促进猪卵母细胞体外成熟和孤雌激活胚胎发育能力的作用,其可能是通过调控脂肪代谢来实现的.

[Objective]This study was conducted to explore the effect of different concentrations of L-carnitine on the maturation of porcine oocytes, the development of parthenogenetic（PA ） embryos in vitro and the lipid metabolism in pig oocytes .[Method] Different concentrations of L-carnitine were add-ed into mature medium to observe the influence on porcine oocytes maturation and parthenogenetic embry -os development .Oil red staining, triacylglycerol kit and quantitative RT-PCR were used to detect the lip-id metabolism and the key hydrolase expression level in oocytes .[Result and conclusion] The rates of oo-cytes maturation and the subsequent PA blastocysts increased significantly when supplemented with 100 ng/mL L-carnitine to the IVM medium（P〈0.05）, and the oocytes lipid metabolism also increased sig-nificantly（P 〈0.001）.The addition of 100 ng/mL L-carnitine into embryo culture medium significantlyincreased the cleavage rates（P 〈0.05）and contributed to the PA blastocyst rates and qualities.Furtheranalyses of quantitative RT-PCR revealed that the mRNA expression levels of adipose triglyceride lipasegene（ATGL）and hormone-sensitive triglayceride lipase gene（HSL）both decreased significantly with100 ng/mL L-carnitine treatment,which indicated that the L-carnitine could affect the lipid metabolismby regulating the key lipases gene expression.In conclusion,these results demonstrated that L-carnitinecan improve porcine oocytes maturation and enhance the PA embryos developmental ability through lipidmetabolism regulation.