Effects of Resveratrol on Aortic Endothelium-Dependent Relaxation in Ovariectomized Rats: The Role of Estrogen Receptor

• Main Authors: Yi Hsin Sun, 孫逸馨
• Other Authors: Y. T. Lau
• Format: Others
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/10714500389189811058

碩士 === 長庚大學 === 生物醫學研究所 === 100 === The higher incidence of cardiovascular disease in men than women has been, in part, correlated with estrogen’s protective effect on endothelial function. Estrogen deficiency induced oxidative damage and leads to the impairment of endothelium-dependent relaxation (EDR), which is corrected by estrogen replacement. Also, resveratrol (RSV) has been reported to lower vascular oxidative stress, and may involve estrogen receptor (ER). We set out to determine whether RSV provides vascular protection in ovariectomized (OVX) rats and whether the effects are mediated through ER-dependent pathway. Female Wistar rats were randomly divided into four groups: Sham, OVX, OVX treated with RSV, and OVX+RSV received an ER antagonist ICI 182,780 for 2 weeks. We found that plasma levels of 17-estradiol were significantly reduced in all OVX rats compared with sham. EDR was decreased, whereas nicotinamide adenine dinucleotide (NADPH) -stimulated aortic superoxide (O2•-) production was increased in OVX rats. Oral administration of RSV significantly attenuated OVX-reduced EDR and prevented NADPH-stimulated superoxide production in OVX+RSV rats. Furthermore, nitric oxide (NO) levels in plasma and aorta were significantly increased in RSV-treated rats. ICI 182,780 abolished the RSV-mediated prevention of OVX-induced oxidative stress and endothelial dysfunction. Therefore, RSV treatment enhanced NO bioavailability to restore the OVX-impaired EDR and reduced O2•- production via ER activation in estrogen-deficient rats.