α亚麻酸对体外成熟人卵母细胞线粒体DNA拷贝数的影响

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），10 μmol/L，50 μmol/L，100 μmol/L，200 μmol/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 50 μmol/L组（70.1%）最高，明显高于对照组（42.1%）及ALA 200 μmol/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 50 μmol/L组（64.4%）最高，明显高于对照组（28.9%）及ALA 200 μmol/L组（18.2%），差异有统计学意义（P＜0.05）；③ALA 50 μmol/L组成熟卵母细胞mtDNA拷贝数（3.64×107±1.85×106）大于对照组（3.42×106±1.95×105），差异有统计学意义（P＜0.05）。结论：50 μmol/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。

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

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 MⅠ stage and 262 oocytes at GⅤ stage. Oocytes with the same proportion of MⅠand GⅤwere 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 0μmol/L (as control) group and the ALA 50μmol/L group were determined by real-time PCR. Results: ①The total maturation rate of the ALA 50 μmol/L group (70.1%) was significantly higher than that of the control group (42.1%) and the ALA 200 μmol/L group (34.1%, both P<0.05). ②The total maturation rate of GⅤ in the ALA 50 μmol/L group (64.4%) was significantly higher than that in the control group (28.9%) and the ALA 200 μmol/L group (18.2%, both P<0.05).③The mtDNA copy number of in vitro matured oocytes in the ALA 50μmol/L group (3.64×107±1.85×106) was significantly higher than that in the ALA 0 μmol/L group (3.42×106±1.95×105, 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.