α- Linolenic Acid Promotes In Vitro Maturation and Quality of Mouse Oocytes with Polycystic Ovarian Syn-drome

Background: The maternally syntheses of mRNAs and pro-teins produced during oocyte growth and maturation. There-fore, the oocyte quality reflected in the stages of embryo devel-opment. In the meanwhile, polycystic ovary syndrome (PCOS) as a reproductive hormonal disorder has oocytes with poor quality under in-vitro fertilization (IVF) cycles. In this regard, a signifiicant improvement in oocyte survival and maturation rates will have a great potential for increasing the effiiciency of IVF. The α-linolenic acid (omega-3) plays an important role in re-productive physiology, affecting oocyte quality. Therefore, this study was planned to investigate beneficial effect of α-linolenic acid (omega-3) in in-vitro oocyte maturation and oocyte quality from PCOS mice.Materials and Methods: Female NMRI mice (25-30 day–old) were divided into two groups: i) Non-PCOS, and ii) PCOS groups. PCOS mouse model induced with 4 mg/kg estradiol valerate dissolved in 0.2mg Sesame oil once a day. After 60 days, the immature follicles were collected from PCOS ovaries, and cultured in the α-MEM medium (minimum essential me-dium: α-MEM) supplemented with 10% bovine serum albumin (BSA) and different concentrations of α-linolenic acid (ALA) (0 [control], 50, and 100 µM). The in-vitro maturation of PCOS oocytes in the different doses of ALA were evaluated and com-pared with control and non-PCOS groups. Also, the expression of TFAM gene in mature oocytes was investigated by Quantita-tive Real Time PCR (QRT-PCR).Results: In this study, the TFAM gene expression was increased during in-vitro maturation of oocytes. TFAM gene was identi-fied by QRT-PCR in all oocyte. However, the TFAM gene ex-pression significantly increased in the MII oocytes supplement-ed with 50µM ALA (95% ± 2.1% vs. 84% ± 2.1%, P=0.005), whereas the gene expression of TFAM in the oocytes treated with higher dose (100 µM of ALA) significantly decreased. Also, the rate of in-vitro maturation of germinal vesicle oocytes treated with 50µM ALA significantly improved in comparison to control group (61/79: 77.2% vs. 59/95: 62.1%).Conclusion: In this study, the TFAM gene expression was increased during in-vitro maturation of oocytes. TFAM gene was identified by QRT-PCR in all oocyte. However, the TFAM gene expression significantly increased in the MII oocytes sup-plemented with 50 µM ALA (95% ± 2.1% vs. 84% ± 2.1%, P =0.005), whereas the gene expression of TFAM in the oocytes treated with higher dose (100 µM of ALA) significantly de-creased. Also, the rate of in-vitro maturation of germinal vesi-cle oocytes treated with 50µM ALA significantly improved in comparison to control group (61/79: 77.2% vs. 59/95: 62.1%).

کلیدواژه ها:

PCOS ، IVM ، Germinal Vesicle ، α-Linolenic Acid ، TFAM Gene