Objective: To study the effects of metformin treatment on bone turnover in women with polycystic ovary syndrome (PCOS), as measured by serum concentrations of bone turnover markers. Design: Post hoc study of a previously conducted prospective multicenter, placebo-controlled, randomized study. Setting: University clinic. Patient(s): The study cohort consisted of 74 non-obese women (body mass index < 27 kg/m 2) and 44 obese women (body mass index R 27 kg/m 2) diagnosed with PCOS, with a mean age of 27.6 AE 4.0 (SD) years. Intervention(s): Randomization to receive metformin or placebo for 3 months. Main Outcome Measure(s): Serum levels of bone formation marker procollagen type I amino-terminal propeptide (PINP) and bone resorption marker carboxy-terminal cross-linking telopeptide of type I collagen (CTX) at baseline and after metformin/placebo treatment. Result(s): Serum levels of PINP and CTX were similar between the metformin and placebo groups at baseline in the whole study population. Obese women, when compared with non-obese, had lower baseline levels of PINP and CTX. Levels of PINP and CTX were significantly reduced in the whole study population, as well as in both non-obese and obese women after 3 months of metformin treatment, whereas no significant changes were observed in the placebo group. Conclusion(s): Metformin treatment, when compared with placebo, was associated with reduced bone turnover, as suggested by reductions in markers of bone formation and resorption, leading to slower bone remodeling in premenopausal women with PCOS. Clinical Trial Registration Number: NCT00994812.

Bone formation markers were decreased in younger women with PCOS when compared with healthy women, which may affect bone mass in these women.

ObjectivesAltered intestinal permeability and gut barrier dysfunction have been suggested to play a role in the pathogenetic mechanism of polycystic ovary syndrome (PCOS), the most common endocrine and metabolic condition in reproductive-aged women. However, data on intestinal permeability and dysbiosis of the gut microbiota in PCOS is still limited, with conflicting results. To this end, the concentrations of gastrointestinal permeability and gut dysbiosis markers were analysed in women with PCOS.DesignCase–control study.SettingGeneral community.Participants104 women with PCOS and 203 body mass index (BMI) matched control women at age 46.Primary and secondary outcome measuresSerum levels of zonulin, fatty acid-binding protein 2 (FABP2), urinary levels of indican, and hormonal and metabolic parameters.ResultsSerum levels of zonulin (128.0±17.0 vs 130.9±14.0 ng/mL, p=0.13) and FABP2 (1.5±0.9 vs 1.5±0.7 ng/mL, p=0.63) and urinary levels of indican (9.5±5.5 vs 8.4±4.2 mg/dL, p=0.07) were comparable in women with PCOS and controls in the whole study population. Likewise, when the study population was divided into different BMI groups as normal weight, overweight and obese, the levels of the above markers were comparable between the study groups. After BMI adjustment, zonulin levels correlated with the levels of high-sensitivity C reactive protein and homoeostasis model assessment of insulin resistance (p<0.05) both in women with PCOS and controls.ConclusionsIntestinal permeability markers zonulin and FABP2, and the dysbiosis marker indican do not seem to be altered in women with PCOS at age 46 compared with BMI-matched controls. Serum zonulin levels correlated with BMI, insulin resistance and inflammatory marker levels, but did not segregate women with PCOS and controls. This suggests that metabolic factors, but not PCOS per se, is the driving force of dysbiosis in premenopausal women with PCOS.