Objective To explore the molecular defects of insulin signalling in polycystic ovary and in vitro effects of troglitazone, one of the insulin sensitizers thiazolidinediones on polycystic ovary syndrome(PCOS) Method The metabolic and mitogenic effects of insulin and insulin like growth factor 1 (IGF 1) were examined in cultured human ovarian luteinizing granulosa cells from PCOS ( n = 11) and normally ovulatory (as control, n = 33) women with vehicle or troglitazone (1 ?g/ml) Results Basal rates were similar, but there were significant decreases in insulin stimulated glucose incorporation into glycogen in PCOS cells, a metabolic action of insulin However, IGF 1 response was found to be about twice greater in PCOS cells at all experimental concentrations with respect to thymidine incorporation compared to control cells, a mitogenic action Troglitazone increased 2 3 fold the insulin induced glycogen synthesis, but reduced the IGF 1 augmented responses of DNA synthesis in PCOS cells to within the range of control granulosa cells As compared with control, PCOS granulosa cells had higher insulin receptor substrate 1 (IRS 1) expression, but lower IRS 2 expression IRS 2 protein levels were increased and IRS 1 levels were reduced by troglitazone treatment, with a greater extent in the former Conclusions There is a selective defect in insulin actions in PCOS granulosa cells, suggesting ovarian insulin resistance and this metabolic phenotype is associated with an enhanced IGF 1 mitogenic potential Troglitazone could divergently alter signal protein expressions and thus insulin actions, as an ovarian insulin sensitizer and mitogen/steroidogenic inhibitor in PCOS

OBJECTIVE: To observe the therapeutic effects of Jinqi Jiangtang Tablet (JQJTT), a commonly prescribed recipe for type 2 diabetes in traditional Chinese medicine, on obese women with polycystic ovary syndrome (PCOS). METHODS: Twenty-four obese women with PCOS were prescribed JQJTT for 3 months and the changes of carbohydrate metabolism and biochemical indicators, including menstrual cycle, body mass index (BMI), the level of blood sex hormone, area under curve (AUC) of glucose and insulin during oral glucose tolerance test (OGTT), and testosterone responses during human chorionic gonadotrophin stimulation ovary test were observed. RESULTS: After treatment, there were significantly reductions in BMI (P<0.05), serum glucose level at 30 min during OGTT (P<0.05) and testosterone levels at eighteen hours during human chorionic gonadotrophin stimulation ovary test (P<0.05). In addition, nine patients had improved cycles among sixteen completed patients, and one patient with clomifene resistance got pregnant with response to clomifene treatment. CONCLUSION: The beneficial effects of JQJTT may result from improvement of carbohydrate metabolism and reduction in androgen biosynthesis in women with PCOS.