The Edible Red Alga Egonori (campylaephora Hypnaeoides J. Agardh) Alleviates Postprandial Blood Glucose Level and High Glucose-Induced Endothelial Dysfunction

Sea algae contain various active components and have health-maintaining and disease-preventing effects. The edible red alga "Egonori" (Campylaephora hypnaeoides J. Agardh) found along the coast of the Japan Sea has a long history of use as a raw material in Japanese local food. However, little is known about its health benefits. In the current study, the effects of a 70 % ethanol extract of Egonori on postprandial hyperglycemia and high glucoseinduced endothelial damage were investigated in mice and cultured endothelial cells, respectively. A 70 % ethanol extract of Egonori alleviated hyperglycemia after oral starch challenge in mice, which was associated with the inhibition of the activity of carbohydrate degrading enzyme a-glucosidase. An in vitro study using a copper (II) reduction assay showed the antioxidant action of Egonori. In addition, the anti-inflammatory effect of Egonori was demonstrated in lipopolysaccharide-induced nitric oxide production in RAW264 cells. In cultured human umbilical vein endothelial cells, Egonori suppressed the high glucose-induced overproduction of reactive oxygen species and cell apoptosis. These results suggest the beneficial effects of Egonori on postprandial hyperglycemia and vascular endothelial cells. Thus, the intake of Egonori before or during a meal may suppress the elevation of the postprandial blood glucose level and attenuate glucose-induced endothelial dysfunction, which leads to the development of atherosclerosis.