α亚麻酸对体外成熟人卵母细胞线粒体DNA拷贝数的影响

Effect of Linolenic Acid on Mitochondrial DNA Copy Numbers of Human Oocyte Derived from in Vitro Maturation

目的：探讨α亚麻酸（ALA）对人未成熟卵母细胞体外成熟的影响及对卵母细胞线粒体DNA拷贝数的影响。方法：收集2014年10月—2015年10月因男方因素行胞浆内单精子注射（ICSI）的273例患者的未成熟卵母细胞441枚,其中MI期179枚,GV期262枚。将MI期和GV期卵母细胞按相同的构成比随机分为5组,分别放入含不同浓度[0（对照组）,10μmol/L,50μmol/L,100μmol/L,200μmol/L]ALA的培养液中,培养24 h后观察卵母细胞的成熟情况,实时荧光定量聚合酶链反应（real-time PCR）测定各组卵母细胞的线粒体DNA（mtDNA）拷贝数。结果：①各组未成熟卵母细胞体外成熟培养（IVM）后总成熟率以ALA 50μmol/L组（70.1%）最高,明显高于对照组（42.1%）及ALA 200μmol/L组（34.1%）,差异有统计学意义（P〈0.05）;②5组GⅤ期卵母细胞成熟率以ALA 50μmol/L组（64.4%）最高,明显高于对照组（28.9%）及ALA 200μmol/L组（18.2%）,差异有统计学意义（P〈0.05）;③ALA 50μmol/L组成熟卵母细胞mtDNA拷贝数（3.64×10^-7±1.85×10^-6）大于对照组（3.42×10^-6±1.95×10^-5）,差异有统计学意义（P〈0.05）。结论：50μmol/L ALA在体外实验中可增加卵母细胞mtDNA拷贝数,有促进人未成熟卵母细胞体外成熟的作用。

Objective： To explore the effect of alpha-linolenic acid （ALA） on human oocytes maturation and the mitochondrial DNA （mtDNA） copy numbers of oocyte. Methods： A total of 441 morphologically normal immature oocytes were recruited from 273 infertile women underwent ICSI in our Center from October 2014 to October 2015. There were 179 oocytes at M I stage and 262 oocytes at G V stage. Oocytes with the same proportion of M I and G V were randomly divided into 5 groups, and in vitro cultured for 24 hours in the medium with ALA at different level [0 （as control）, 10 μmol/L, 50 μmol/L, 100 μmol/L, 200 μmol/L]. The oocyte maturation was observed, and the mtDNA copy numbers in the ALA 0 pmol/L （as control） group and the ALA 50 μmol/L group were determined by real-time PCR. Results： ①The total maturation rate of the ALA 50 pmol/L group （70.1%） was significantly higher than that of the control group （42.1%） and the ALA 200 pmol/L group （34.1% , both P 〈0 .0 5 ） .② The total maturation rate of G V in the ALA 50 pmol/L group （64.4% ） was significantly higher than that in the control group （28.9%） and the ALA 200 pmol/L group （18.2%, both P〈 0.05）.③The mtDNA copy number of in vitro matured oocytes in the ALA 50 pmol/L group （3.64×10^7± 1.85×10^6） was significantly higher than that in the ALA 0 μmol/L group （3.42×10^6±1.95×10^5, P〈0.05）. Conclusions： 50μmol/L ALA can increase the mtDNA copy number of the in vitro matured human oocyte, suggesting that ALA can promote the in vitro maturation of human oocyte.