Changes in the IGF-1 and TNF-α synthesis pathways before and after three-month reduction diet with low glicemic index in women with PCOS

Abstract

OBJECTIVES: An increase in IGF-I and TNF-α may be a cardioprotective effect. To examine the relationships between IGF-I and TNF-α and test the anthropometric and biochemical parameters before and after a low-glycemic index reduction diet using a correlation matrix. MATERIAL AND METHODS: Twenty-two women diagnosed with PCOS according to Rotterdam's criteria were eligible for this study, which analysed the results before and after a three months dietary intervention. Body composition measurements were determined by bioimpedance and performed twice, along with the labelling of lipid, carbohydrate and hormonal profiles. IGF-I and TNF-α were also determined in the serum. RESULTS: Before dietary intervention, a significant correlation was observed. A correlation was also noted between the increase in TNF-α and DHEA-SO4, FSH, glucose level and total cholesterol. The increase in IGF-I was not related to anth-ropometric measurements: however, its concentration was observed to be related to the level of SHBG and HDL. After dietary intervention, the correlation between TNF-α and muscle mass percentage was confirmed, as was the correlation between WHR and fasting blood glucose levels. A significant negative correlation was observed between extracellular water, provided in litres, and SHBG level. CONCLUSIONS: One important role of IGF-I in PCOS pathogenesis is the stimulation of increased synthesis of SHBG and HDL. The increased level of IGF-I after the reduction diet had a cardioprotective effect. TNF-α inhibits FSH synthesis, preventing the growth of numerous follicles. Its synthesis is also related to DHEA-SO₄. After three-month reduction diet does not significantly reduce TNF-α.