Interestingly, melatonin treatment displayed beneficial effects on insulin levels and insulin resistance index (HOMA-IR), as well as on cholesterol levels, and peroxisome proliferator-activated receptor -γ (PPAR-γ) and low-density lipoprotein receptor (LDLR) expression among women with PCOS; moreover, an improvement of mental health parameters was also observed [50]. The gene discussed is LDLR; the disease is polycystic ovary syndrome.