Exploring ovarian aging: unraveling the link between mitochondria status and oocyte as a determinant of gamete quality.

The variation in reproductive age among individuals is significant, with many cases of infertility involving premature ovarian aging. This issue, combined with the societal trend of delaying childbearing, leads to age-related ovarian dysfunction. Ovarian aging is related to a decline of ovarian reserve, as oocyte quantity, quality, and precocious senescence, and may affect fertility and the overall individual well-being. Mitochondria play a central role in the maintenance of any cell health. Then mitochondrial dysfunctions may be responsible also for a negative impact on the quality, number, and function of oocytes, leading to different age-related reproductive disorders, impaired oogenesis, and embryogenesis. Although a large number of researches have shown clearly that mitochondrial dysfunction and morphology changes affect the maintenance and function of all major organs and tissues, such as the brain, heart, skeletal muscle, liver, and others the mechanisms contributing to early ovarian aging, a decrease of oocyte quality, and infertility remain unclear. In this review, we summarize the role of mitochondrial dysfunction in ovarian aging, presenting recent findings on morpho-functional changes in these organelles, and highlighting how their dysfunction accelerates ovary and cell senescence. We also explore their impact on oocyte functions. The reported data highlight the critical role of mitochondria in maintaining and enhancing oocyte quality, indicating that future studies should further focus on the mechanisms underlying mitochondrial damage and on identifying mitochondrial targets that may offer promising strategies to preserve, recover, and extend fertility in aging women.