由於現在生活品質的提升,使得飲食習慣改變,導致心血管疾病增加,動脈粥狀硬化則為其主要的危險因子。而低密度脂蛋白(LDL)的氧化修飾以及巨噬細胞所受到的脂質過氧化作用皆在動脈粥狀硬化的過程中扮演了重要的角色,另外由高脂質飲食所導致的高血脂症以及脂肪肝現象也被認為和動脈粥狀硬化的形成有關。仙人掌果實中的色素有良好的抗氧化能力,因此本實驗之目的為評估仙人掌果肉萃取物(OFP)是否能夠藉由抑制LDL和巨噬細胞所受的氧化以及泡沫細胞的形成,並且降低血脂與脂肪肝來達到抗動脈粥狀硬化之作用。在預試驗中,OFP有良好的捕捉自由基作用,因此以OFP進行進一步的活性研究。在體外抗氧化實驗中,利用LDL electrophoretic mobility、TBARS生成濃度、apoB斷裂、共軛雙烯測定、總膽固醇的測定等實驗證實了OFP能夠抑制LDL的氧化。在細胞實驗中也證明了OFP能減少LPS誘導巨噬細胞產生一氧化氮以及對其造成的脂質過氧化作用,並且減少泡沫細胞的形成。動物實驗中利用餵食高脂質飼料的大白鼠也可以發現OFP能降低由高脂質飲食引起的高血脂以及脂肪肝現象。由以上結果可以得知OFP確實有良好的抗氧化效果,而且對於預防動脈粥狀硬化應該有不錯的功效,或許能夠應用於保健食品的開發。
Atherosclerosis is one of the major risk factors for heart disease. LDL oxidation and lipid peroxidation of macrophages play important roles in atherosclerosis. Furthermore, high fat diet induced hyperlipidemia and fatty liver disease are also related to atherosclerosis. The pigments of Opuntia dillenii fruit was found to possess antioxidative activity. In this study, we evaluated the antioxidative activity of the Opuntia dillenii fruit pulp extracts (OFP), and whether OFP could prevent high cholesterol diet induced hyperlipidemia and fatty liver. In preliminary study, we found that both Opuntia dillenii fruit pulp and skin extracts had good free radical-quenching capacity . Because OFP had better capacity,we chose it to carry on our further researches. The antioxidative activity of OFP on LDL oxidation was defined by relative electrophoretic mobility (REM), apoB fragmentation, thiobarbituric acid reactive substance (TBARS) assay, diene conjugation, and total cholesterol assay. The results showed OFP was able to scavenge free radical and inhibit LDL oxidation. OFP could decrease the production of NO and lipid peroxideation induced by LPS also inhibited foam cell formation in macrophage. In the in vivo experiment, Wistar rats fed high fat diet were used as the animal model. The results showed that OFP could prevent high fat diet induced hyperlipidemia and fatty liver. In conclusion, OFP possess strong antioxidative activity, and may have anti-atherosclerosis effects. Therefore, fruit of Opuntia dillenii is suggested to be a heathy food.