Alpha Lipoic Acid Upregulates Mitochondrial DNA Copy Number of Mouse Ovarian Follicles during In Vitro Culture
Sara Seifi
1
(
School of Biology, Damghan University, Damghan, Iran
)
Saeed Zavareh
2
(
School of Biology, Damghan University, Damghan, Iran|Institute of Biological Sciences, Damghan University, Damghan, Iran
)
Meysam Nasiri
3
(
School of Biology, Damghan University, Damghan, Iran|Institute of Biological Sciences, Damghan University, Damghan, Iran
)
Keywords: mtDNA, Alpha lipoic acid, Ovarian follicle, Tfam,
Abstract :
The objective of this study was to investigate the influence of alpha lipoic acid (ALA) on the expression of the Tfam gene and the copy number of mtDNA in preantral follicles (PFs) of mice during in vitro culture. PFs were mechanically isolated from 14-day-old National Medical Research Institute (NMRI) mice and subjected to a 12-day culture in the presence of 100µm ALA, followed by hCG-induced ovulation. The developmental parameters of PFs and oocyte maturation were evaluated, and the expression of the Transcription Factor A, Mitochondrial (Tfam) gene, along with mtDNA copy number in granulosa cells and oocytes, were measured using real-time PCR. The results showed that ALA-treated groups exhibited significantly higher diameter of PFs and survival rate, antrum formation, and MII oocytes rate in comparison to the control groups (P<0.05). Furthermore, Tfam gene expression significantly increased in granulosa cells and oocytes of the ALA groups in comparison with the control group, and the mtDNA copy number in granulosa cells and oocytes of the ALA-treated group was significantly higher than that of the control groups (P<0.05). Supplementing the culture medium with ALA demonstrated an improvement in PFs' developmental competence, likely mediated by the upregulation of Tfam gene expression and an increase in mtDNA copy number in oocytes and granulosa cells.