Melatonin in ovarian function and dysfunction: Molecular mechanisms and therapeutic potential

Melatonin (MT) is a natural indoleamine compound. In addition to regulating sleep and circadian rhythms, MT exhibits antioxidative, anti-inflammatory, anti-apoptotic, and ovarian protective properties. Recent studies have shown that MT alleviates polycystic ovary syndrome (PCOS), premature ovarian insufficiency (POI), ovarian injury, and age-related ovarian function decline. This review establishes an integrated mechanistic model in which oxidative stress, mitochondrial dysfunction, inflammatory responses, and autophagic imbalance collectively contribute to the pathogenesis of ovarian disorders, while melatonin acts as a pleiotropic regulator that counteracts these interconnected pathological pathways. Furthermore, this review also discusses recent advances regarding the inhibitory effects of melatonin on ovarian tumors. Although MT shows considerable clinical promise, further research is needed to determine its optimal dosage, administration regimens, and therapeutic targets to facilitate its clinical translation.