Resveratrol attenuates ovariectomy-induced hypertension and bone loss in stroke-prone spontaneously hypertensive rats

Abstract

We examined the effect of resveratrol (3,4',5-trihydroxy stilbene), a phenolic compound found in the skins of most grapes, on blood pressure and bone loss in ovariectomized (OVX), stroke-prone spontaneously hypertensive rats (SHRSP). Nineteen-week-old female SHRSP were divided into a sham- ovariectomized (sham) group fed a control diet and two OVX groups fed either a control diet (OVX-Cont) or a diet supplemented with resveratrol (5 mg/kg per d; OVX-Resv). Ovariectomy induced significant increases in systolic blood pressure (SBP). Resveratrol lowered the SBP by 15% by the third week of administration, and this effect was maintained throughout the study. Resveratrol treatment also significantly enhanced endothelium-dependent vascular relaxation in response to acetylcholine (ACh) in OVX rats. Finally, femur breaking energies measured for the resveratrol-treated (OVX-Resv) group were significantly higher than those of the resveratrol-untreated (OVX-Cont) group. While no significant differences in calcium, magnesium and phosphorus content were found between the femurs of OVX-Cont and OVX-Resv rats, the femur hydroxyproline content in the OVX-Resv group was significantly higher than of the OVX-Cont group. We conclude that, in OVX-SHRSP, resveratrol acts by a similar mechanism to mammalian estrogens, lowering blood pressure by increasing dilatory responses to ACh. The present study also demonstrated that resveratrol was able to prevent ovariectomy-induced decreases in femoral bone strength.