Abstract
Effects of dietary chrysin supplementation on blood pressure and oxidative status of rats were studied in comparison with quercetin. Rats were fed a control diet or a high-fat high-sucrose (HFS) diet with or without 0.25% flavonoids (chrysin or quercetin) for 4 weeks. In rats fed the HFS diet without flavonoids, there was a significant elevation of blood pressure, increase in aortic NADPH oxidase but not xanthine oxidase, an increase in plasma lipid peroxides, and a decrease in liver glutathione, compared to rats fed the control diet. Chrysin suppressed the elevation of blood pressure in rats fed the HFS diets at the same level as quercetin. Chrysin supplementation did not suppress the increase in NADPH oxidase activity and plasma lipid peroxides or the decrease in liver glutathione, whereas these effects were significant with quercetin. Also, the results of an in vitro experiment suggested that chrysin did not exert antioxidative effects on lipid peroxidation in a linoleic acid emulsion. These results suggest that chrysin has an antihypertensive effect similar to quercetin, but unlike quercetin is not antioxidative in normotensive rats fed a HFS diet. Thus, it is probable that a mechanism(s) other than antioxidative activity is responsible for the suppression of hypertension by chrysin.
