洛神花(Hibiscus Sabdariffa Linnaeus)為錦葵科(Malvaceae)植物，原產熱帶地區，分佈於印度，馬來西亞及東南亞，台灣東部及南部也有盛產。其花成分中含有機酸、類黃酮素、黃酮素及多酚酸等。根據國外之研究，在體外試驗顯示其水萃取物具有抗痙攣，降膽固醇，降血壓及抗菌作用。洛神花成份中類黃酮素具有抗氧化及抑制心血管疾病，原兒茶酸則可抑制化學致癌物誘導之癌化，從本研究室以往的研究也顯示洛神花具有抑制動脈硬化生成與降低大鼠及大白兔血中三酸甘油酯及總膽固醇含量的作用。因此，本試驗想進一步探討洛神花萃取物對於治療模式之動脈硬化中所扮演的角色。本研究顯示在以1.3%膽固醇及3%豬油餵食10週之兔子成功誘導高血脂症，隨後進行餵食洛神花水萃取物後發現，若未經餵食洛神花萃取物之試驗動物組死亡率偏高。一經餵食洛神花萃取物後隨著劑量增加之試驗組別的動物死亡率有降低之現象。此外，1%洛神花水萃取物具有顯著抑制血清中三酸甘油酯及膽固醇含量之作用，並能增加HDL-C及降低LDL-C；進一步以病理學觀察也顯示洛神花水萃取物具有抑制動脈硬化形成之作用，其中包含泡沫細胞之沉積量明顯減少，且能抑制平滑肌細胞位移及動脈硬化斑內鈣化現象之消失。在經由20週之長期試驗下，顯示1%洛神花萃取物具有有效抑制動脈硬化、降低血中三酸甘油酯及總膽固醇含量，因而以降低由動脈硬化症所導致的動物死亡。因此，我們可初步推測洛神花萃取物具有開發作為治療動脈硬化之潛力。
Hibiscus sabdariffa L., a local soft drink material and medicinal herb containing organic acid, isoflavonids, flavonid and polyphenolic acid, is often used in folk medicines to treat hypertension, pyrexia and liver disorders. In one of our previous in vivo studies, we reported that HSE (Hibiscus sabdariffa extract) could reduce hyperlipidemia and atherosclerosis. In this study, we investigate whether HSE can be used to reduce atherosclerosis in experimental rabbits with that disease. In this study, we induced atherosclerosis in New Zealand White (NZW) by feeding them a normal diet plus high amounts of cholesterol (1.3%) and lard oil (3%) for 10 weeks. Once found to have atherosclerosis, the rabbits were divided into 4 groups and put on different experimental diets with or without 0.5 or 1% HSE for another 10 weeks. The animals that continued on the high cholesterol diet but were not fed HSE died within 4 week. Those fed with 0.5 or 1% HSE were found to experience a reduction in death rate 10 weeks later. The animals on a normal diet and HSE had lower level of triglyceride, cholesterol and low-density lipoprotein-cholesterol (LDL-C) levels than those on high cholesterol diets. Feeding HSE to rabbits also significantly reduced severe atherosclerosis of the aorta. Histopathological examination showed that HSE reduced foam cell formation, inhibited smooth muscle cell migration and calcification in the blood vessel of rabbits. These results suggest that HSE has the ability to reduce serum lipids and atherosclerotic activity and, therefore, may be potentially developed into an alternative means of treating atherosclerosis.
