Genistein and exercise do not improve cardiovascular risk factors in the ovariectomized rat

To investigate the effect of either genistein, or exercise, or both, on parameters that are indicators of cardiovascular health.

We investigated the effect of genistein treatment (300 mg genisten/kg body weight/day), or exercise training, or combined genistein and exercise training, for a period of 6 weeks on physical characteristics, cardiovascular plasma markers, blood pressure, aortic morphology, cardiac structure and oxidative stress in the ovariectomized (OVX) Sprague-Dawley rat. Comparisons were made with intact rats.

Ovariectomy (compared to intact) resulted in significant decreases in uterine weight (6-fold, p < 0.0001), insulin levels (4-fold, p = 0.0214), insulin/glucose ratio (3-fold, p = 0.0029), and tumor necrosis factor-α plasma levels (2-fold, p < 0.0001). Similarly, aortic blood pressure was significantly increased (by 8%, p < 0.0033) in OVX rats, without changes in aortic luminal or wall dimensions. Heart surface area was significantly increased (by 16%, p = 0.0160) in OVX rats and this was without changes in non-protein thiol levels (a marker of oxidative stress). Physical characteristics were not altered by treatment with genistein, or genistein with exercise, with the exception of increased uterine weight in OVX rats treated under these same conditions. There were no effects of genistein or exercise on indices of blood pressure and aortic morphology in the OVX rat. However, right ventricular nuclei count was reduced in sedentary genistein-treated rats compared to non-treated control OVX rats.

Our results indicate that administration of genistein at this dose, treadmill running, or the combination of both, are not associated with any improvement in cardiovascular function and structure, and risk factors in an ovariectomy model of postmenopause.