Dietary Soy Isoflavones Prevent Metabolic Disturbs Associated with a Deleterious Combination of Obesity and Menopause.

This study aimed to evaluate the effects of soy isoflavone supplementation (25 mg/kg) on insulin resistance and inflammation in adipose tissue in an experimental model of menopause-obesity. Twenty-four female Wistar rats were ovariectomized (O) and distributed among the groups: OSD-ovariectomized rats submitted to normocaloric standard diet ( n  = 6); OHF-ovariectomized rats submitted to high-fat diet ( n  = 9); and OHFI-ovariectomized rats submitted to high-fat diet with isoflavones ( n  = 9). Weight gain, body adiposity, food and caloric intake, blood pressure, and glucose tolerance were assessed. After 24 weeks, the rats were euthanized; the thoracic blood collected for serum insulin determination and the homeostatic model assessment-insulin resistance) (HOMA-IR) and homeostatic model assessment- β cell (HOMA- β ) indices were calculated. Abdominal adipose tissues were removed, weighed, and fixed for immunohistochemical and morphometric studies. Isoflavones decreased weight gain and blood pressure without changing the food and caloric intake ( P  < .05). Isoflavones did not affect the weight of the abdominal adipose tissue depots ( P  < .05). Although they did not alter glucose tolerance, the isoflavones reduced HOMA-IR and HOMA- β , serum insulin levels, in addition to reducing adipocytes' size ( P  < .05). The number of macrophages, lymphocytes, and crown-like structures in adipose tissue was lower in the group treated with isoflavones ( P  < .05). In conclusion, our data show that dietary soy isoflavones' supplementation prevents many of well-known deleterious combination of obesity and menopause on metabolism, such as body overweight, adipocyte hypertrophy, and hypertension, as well as insulin resistance and adipose tissue inflammation.