Comparison of myo-inositol and metformin on clinical, metabolic and genetic parameters in polycystic ovary syndrome: A randomized controlled clinical trial.

OBJECTIVE: To our knowledge, data on comparison of myo-inositol and metformin on clinical, metabolic and genetic parameters in subjects with polycystic ovary syndrome (PCOS) are limited. This study was carried out to compare myo-inositol and metformin on clinical, metabolic and genetic parameters in subjects with PCOS.

DESIGN, PATIENTS AND MEASUREMENTS: This randomized controlled trial was conducted among 60 subjects with PCOS aged 18-40 years. Subjects were randomly allocated into two groups to receive either myo-inositol (N=30) or metformin (N=30) for 12 weeks. Gene expression of inflammatory cytokines was assessed in peripheral blood mononuclear cells (PBMCs) of PCOS women by RT-PCR.

RESULTS: After the 12-week intervention, compared with metformin, myo-inositol intake significantly decreased serum total testosterone (-1.4±4.2 vs +0.7±1.4 nmol/L, P=.03), modified Ferriman-Gallwey (mF-G) scores (-1.1±0.7 vs -0.5±0.8, P=.01) and serum high-sensitivity C-reactive protein (hs-CRP) levels (-2.6±3.9 vs +0.2±1.5 mg/L, P<.001). RT-PCR demonstrated that compared with metformin, myo-inositol downregulated gene expression of interleukin-1 (IL-1) (P=.02) in PBMCs of subjects with PCOS. We did not observe any significant effect of myo-inositol intake compared with metformin on other hormonal profiles, plasma nitric oxide (NO) or gene expression of IL-8 and tumour necrosis factor alpha (TNF-α).

CONCLUSIONS: Overall, taking myo-inositol, compared with metformin, for 12 weeks in patients with PCOS with hyperinsulinism and normoinsulinism had beneficial effects on total testosterone, mFG scores, serum hs-CRP levels and gene expression of IL-1, but did not affect other hormonal profiles, NO levels or gene expression of IL-8 and TNF-α.