Effects of melatonin administration on mental health parameters, metabolic and genetic profiles in women with polycystic ovary syndrome: A randomized, double-blind, placebo-controlled trial

Objective: The aim of this study was to evaluate the effect of melatonin supplementation on mental health parameters, metabolic and genetic parameters in women suffering from polycystic ovary syndrome (PCOS). Methods: This randomized, double-blinded, placebo-controlled clinical trial was performed on 58 subjects, aged 18–40 years old. Subjects were randomly allocated to take either 10 mg melatonin (2 melatonin capsules, 5 mg each) (n = 29) or placebo (n = 29) once a day 1 h before bedtime for 12 weeks. Glycemic control and lipid profiles were measured at baseline and after the 12-week intervention. Using RT-PCR method, gene expression related to insulin and lipid metabolism was conducted on peripheral blood mononuclear cells (PBMCs) of PCOS women. Results: Melatonin supplementation significantly decreased Pittsburgh Sleep Quality Index (β −2.15; 95% CI, −3.62, −0.68; P = 0.005), Beck Depression Inventory index (β −3.62; 95% CI, −5.53, −1.78; P<0.001) and Beck Anxiety Inventory index (β −1.95; 95% CI, −3.41, −0.48; P = 0.01) compared with the placebo. In addition, melatonin administration, compared with the placebo, significantly reduced serum insulin (β −1.20 µIU/mL; 95% CI, −2.14, −0.26; P = 0.01), homeostasis model of assessment-insulin resistance (HOMA-IR) (β −0.28; 95% CI, −0.50, −0.05; P = 0.01), serum total- (β −7.96 mg/dL; 95% CI, −13.75, −2.17; P = 0.008) and LDL-cholesterol levels (β −5.88 mg/dL; 95% CI, −11.42, −0.33; P = 0.03), and significantly increased the quantitative insulin sensitivity check index (QUICKI) (β 0.008; 95% CI, 0.002, 0.014; P = 0.007). Moreover, melatonin supplementation upregulated gene expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) (P = 0.004) and low-density lipoprotein receptor (LDLR) (P = 0.01) compared with the placebo. Conclusions: Overall, melatonin administration for 12 weeks had beneficial effects on mental health parameters, insulin levels, HOMA-IR, QUICKI, total- and LDL-cholesterol levels, and gene expression of PPAR-γ and LDLR among women with PCOS.