Soy isoflavones affect platelet thromboxane A2 receptor density but not plasma lipids in menopausal women

Abstract

Objectives: It has been suggested that isoflavones protect the cardiovascular system, in part by improving lipid profile. The purpose of the present research was to examine the effect of a 12-week soy isoflavone supplementation on lipoprotein status and platelet thromboxane A2 receptor density. Methods: Twenty-nine healthy postmenopausal women were invited to take part in a randomised study to receive either 100 mg/day isoflavone supplement (n = 15) or identical placebo capsules (n = 14). Blood samples obtained at baseline and after 12 weeks were analysed for isoflavones, total cholesterol, high density lipoprotein cholesterol, triglycerides, glucose, insulin, estradiol, testosterone, gonadotrophins, sex hormone-binding globulin (SHBG) and platelet thromboxane A2 receptor density. Blood pressure measurements, body mass index, subcutaneous fat at entrance and at the end of treatment were also registered. Changes in variables between groups were compared by ANOVA for repeated measures. R