Laboratory of Animal Physiology, Graduate School of Environmental and Life Science, Okayama University.
K.I Chemical Industry Co., Ltd.
Biol Pharm Bull. 2020;43(3):404-408. doi: 10.1248/bpb.b19-01013.
The aim of this study was to investigate the effects of egg yolk powder enriched with astaxanthin (ASX-E) on blood pressure in spontaneously hypertensive rats (SHR) and to verify the benefits of ASX-E as a functional food. To investigate the antihypertensive effect, SHR were fed with an ASX-E mixed diet before hypertension development. Blood pressures were determined periodically during the study by the tail-cuff method. At the end of the study, animals were euthanized, and their thoracic aortas were collected to determine vascular conductance. The thoracic aorta tension was measured with a force displacement transducer. Concentration-dependent response relationships were determined by cumulative addition of 10-10 M Carbamoylcholine (Cch). Blood pressures of the SHR in the ASX-E mixed diet group were ASX-dose-dependently lower than that of those in the control group. In SHR fed with an ASX-E mixed diet, Cch induced vasorelaxation in the thoracic aorta with endothelium lining but not without endothelium. However, the antihypertensive effect of ASX-E was not observed on blood pressures in SHR that were fed with ASX-E only after the development of hypertension. Results suggest that ASX-E protects endothelial function and thereby prevents the development of hypertension. Hence, the results of our research indicate that daily consumption of ASX-E has a potential benefit on human health.
本研究旨在探讨富含虾青素（ASX）的蛋黄粉（ASX-E）对自发性高血压大鼠（SHR）血压的影响，并验证 ASX-E 作为功能性食品的益处。为了研究降压效果，在高血压发生前，SHR 喂食添加 ASX-E 的混合饮食。通过尾套法定期在研究期间测定血压。研究结束时，处死动物，采集其胸主动脉以测定血管传导性。使用力位移换能器测量胸主动脉张力。通过累积添加 10-10 M Carbamoylcholine（Cch）确定浓度依赖性反应关系。与对照组相比，喂食添加 ASX-E 的混合饮食的 SHR 的血压呈 ASX 剂量依赖性降低。在喂食添加 ASX-E 的混合饮食的 SHR 中，Cch 诱导内皮衬里的胸主动脉血管舒张，但没有内皮衬里则没有。然而，在高血压发生后，仅喂食 ASX-E 的 SHR 的血压并未观察到 ASX-E 的降压作用。结果表明，ASX-E 可保护内皮功能，从而预防高血压的发生。因此，我们的研究结果表明，每日食用 ASX-E 对人类健康具有潜在益处。
