OBJECTIVE: To determine the clinical, hormonal and biochemical effect of 4-5 months of insulin-sensitizing therapy (hypocaloric diet+metformin) in obese patients with polycystic ovary syndrome (PCOS). DESIGN: Prospective study. METHODS: Twenty-three obese patients with PCOS, 19 obese patients without menstrual disturbances and 11 healthy control women were recruited from the Department of Endocrinology and Endocrine Gynecology, Medical Academy, Bialystok, Poland. Obese patients received 500 mg metformin together with hypocaloric diet three times daily for 4-5 months, after baseline study. The clinical parameters, menstrual pattern and serum concentrations of insulin, leptin, IGF-I, insulin-dependent proteins (sex hormone-binding protein (SHBG), insulin-like growth factor-binding protein-1 (IGFBP-1)), gonadotropins and sex steroids were determined before and after treatment. RESULTS: In the baseline study, obese patients with PCOS had significantly higher insulin, testosterone and LH concentrations in comparison with the other groups. The serum leptin, IGF-I, IGFBP-1 and SHBG were not different between the two groups of obese patients, but there was a significant difference in comparison with the control group. After metformin therapy a significant reduction in BMI, % of body fat and leptin concentration were observed in both groups of obese patients. Fasting insulin, testosterone and LH concentrations decreased significantly only in the PCOS group. Six out of 11 patients in the PCOS group had more regular menstrual cycles; two patients conceived. CONCLUSIONS: Insulin-sensitizing therapy could be considered as an additional therapeutic option in obese women with PCOS.
I Kowalska, M Kinalski, M Straczkowski, S Wolczyski and I Kinalska
M Straczkowski, I Kowalska, S Dzienis-Straczkowska, A Stepien, E Skibinska, M Szelachowska and I Kinalska
OBJECTIVE: Tumor necrosis factor-alpha (TNFalpha) plays an important role in the pathogenesis of insulin resistance and type 2 diabetes. Plasma levels of the soluble (s) fractions of TNFalpha receptors, especially sTNFR2, are good indicators of TNFalpha system activation in obesity. The aim of the present study was to assess the effect of exercise training on the TNFalpha system and to evaluate the relationship with changes in insulin sensitivity. DESIGN AND METHODS: Sixteen obese women (body mass index (BMI)>27.8 kg/m(2)), 8 with normal (NGT) and 8 with impaired glucose tolerance (IGT), participated in an exercise training program which lasted for 12 weeks and included exercise performed on a bicycle ergometer at an individual intensity of 70% maximal heart rate, for 30 min, 5 days a week. Anthropometrical measurements and blood biochemical analyses were performed, and plasma TNFalpha, sTNFR1 and sTNFR2 levels were assessed. Insulin sensitivity was evaluated using the hyperinsulinemic euglycemic clamp technique (insulin infusion: 50 mU x kg(-1)xh(-1)). RESULTS: At baseline, despite similar anthropometrical parameters, IGT subjects were markedly more insulin resistant and had higher TNFalpha and sTNFR2 concentrations. Exercise training increased insulin sensitivity and decreased TNFalpha and sTNFR2 levels, while sTNFR1 remained unchanged. The decrease in sTNFR2 was significantly related to the increase in insulin sensitivity; that relationship remained significant after adjustment for the concurrent changes in BMI, waist circumference, percentage of body fat, plasma glucose, insulin and free fatty acids. CONCLUSIONS: Regular physical exercise decreases TNFalpha system activity and that decrease may be responsible for the concurrent increase in insulin sensitivity.