Protective effect of soluble fiber from Undaria pinnatifida on vascular endothelium in hypercholesterolemic rabbits.

Dietary fiber could improve endothelial function and abnormal production of nitric oxide (NO) and elevated endothelin-1 (ET-1) concentration induce endothelial dysfunction. In the present study, we tested the effect of soluble fiber extracted from Undaria pinnatifida (UP) on endothelial function and NO and ET-1 production in hypercholesterolemic rabbits. After treatment with UP soluble fiber (5 or 10%) for 8 wk, endothelium-dependent vasorelaxation in isolated aortic rings, the concentrations of NO and ET-1 and malondialdehyde (MDA), and the expression of endothelial NO synthase (eNOS) gene were measured. The UP soluble fiber (5 or 10%) treatment significantly attenuated the impairment of endothelium-dependent vasorelaxation concomitantly with increase of plasma NO concentration and expression of aortic endothelial nitric oxide synthase (eNOS), reduction of plasma MDA level and ET-1 concentration and aortic ET-1 concentration. The present study indicates that the protective effects of UP soluble fiber on ...