山苦瓜改善血糖血脂代謝異常之效應探討

Momordica charantia L. improve high fat diet-induced glucose intolerance and hyperlipidemia in rats and mice

10.6342/NTU.2005.02556

謝婉郁

代謝症候群 ； 山苦瓜 ； OGTT ； metabolic syndrome ； Momordica charantia L. ； OGTT ； PPAR

臺灣大學微生物與生化學研究所學位論文

2005年

碩士

黃青真

繁體中文

代謝症候群指血糖調節異常 (胰島素抗性)、高血脂、中心型肥胖、高血壓等至少三項同時存在者，未經適當控制則具有極高之風險轉為第二型糖尿病及動脈粥狀硬化。PPARs (Peroxisome proliferators activated receptors) 為核受器家族的一員，受 ligand 活化後可啟動下游基因的轉錄，主調控葡萄糖及脂質代謝、運輸及貯存相關基因之表現。本實驗室在過去的研究中顯示，山苦瓜 (Momordica charantia L.) 乙酸乙酯萃物中含有可活化 PPARα 與 PPARγ 之成分，可調控其下游基因之表現。本研究先以高脂飲食誘發 C57BL/6J 小鼠產生血糖、血脂代謝異常現象，探討餵食山苦瓜全果凍乾粉末或其乙酸乙酯萃物，對小鼠體內葡萄糖及脂質代謝與肝臟 PPARα 相關基因表現之影響。分別餵食 C57BL/6J 小鼠含5% 大豆油 (B) 或30% 奶油 (C) 之實驗飼料 16 週後，C 組血糖、胰島素及血清中三酸甘油酯 (TG) 濃度顯著較 B 組高。再將 C 組小鼠隨機分為五組，一組維持原飼料，兩組分別更換為含有5% 山苦瓜全果凍乾粉末 (BGP) 及0.25% 山苦瓜乙酸乙酯萃物 (EAE) 之高油脂飼料，另外以含有0.5% clofibrate (CF) 或 0.004% rosiglitazone (R) 之高油脂飼料作為正對照組。繼續飼養四週後，BGP 組之血糖顯著低於 C 組 (p < 0.05)。飼養九週後，相較於 C 組，BGP 組體內葡萄糖耐受性顯著佳 (p < 0.05)。飼養 11 週後犧牲， BGP 組之體重增加量、血脂質、肝脂質皆顯著低於對照組C組。而 EAE 組在血脂、肝脂之部分指標顯著低於對照組 C 組。改以餵食 Wistar 大鼠含 5% 大豆油 (B) 或 30% 奶油 (C) 之實驗飼料 3 週後，C 組大鼠體重顯著高於 B 組。再將 C 組大鼠隨機分為六組，一組維持原飼料，三組分別更換為含有5% 山苦瓜全果凍乾粉末 (BGP)、1% 山苦瓜乙酸乙酯萃物 (EAE) 或 3% 山苦瓜酒精萃物之高油脂飼料，另外以含有1% clofibrate (CF) 或 0.01% rosiglitazone (R) 之高油脂飼料作為正對照組。飼養四週後，C 組出現口服葡萄糖耐受性較差，但 BGP 組則否 (p < 0.05)。飼養五週後犧牲，結果顯示 BGP 組之腹脂重量顯著低於對照組C 組，且山苦瓜全果凍乾粉末及其乙酸乙酯、酒精萃物可預防因高脂飲食造成的高血糖、高血清胰島素等症狀。此外，攝取山苦瓜全果凍乾粉末或其乙酸乙酯萃物能顯著誘發 β-oxidation 之關鍵酵素 acyl-CoA oxidase mRNA 之表現。綜合上述結果可知，5% 山苦瓜全果凍乾物可改善高脂飲食誘導之體重增加、高血糖、高血脂及葡萄糖不耐現象，可開發為調節血糖與血脂之功能性食品。

Metabolic syndrome, which develops as a result of insulin resistance, is characterized by obesity, glucose intolerance, hyperinsulinemia, dyslipidemia, and hypertension. Peroxisome proliferators-activated receptors (PPARs), ligand-dependent transcription factors that regulate the expression of genes involved in glucose and lipid homeostasis, are molecular targets of well-known therapeutic agents of hyperlipidemia and insulin resistance. Ethyl acetate (EA) extract of bitter gourd (momordica Charantia) has been found to active PPARα and PPARγ significantly. High-fat diet induced obesity rodent model was therefore employed in this study to investigate the effects of Momordica charantia L. on glucose and lipid metabolism. A few PPARα target gene expressions in liver were also examined. In experiment 1, C57BL/6J mice were prefed a high butterfat diet (30%) for 16 weeks for the development of hyperglycemia and hyperlipidemia. These animals were then assigned to 5 groups and respectively fed the high butter fat diet supplemented with none (the C diet group), 5% wild bitter ground powder (the BGP diet group), 0.25% of BGP ethyl acetate extract (the EAE diet group), 0.5% clofibrate (the CF diet group) or 0.004% rosiglitazone (the R group) for 11 weeks. A group of mice was simultaneously fed a basal diet (5% soybean oil, the B diet group) for a total of 27 weeks and serve as the normal control. Hyperglycemia, glucose intolerance, hypertriglyceridemia and hypercholesterolemia were observed in the C group but were significantly improved in the BGP group. In experiment 2, Wistar rats were respectively fed the basal diet (B), or the high butter fat diets for 3 weeks. The high fat fed groups were then assigned to 6 groups and respectively fed the high butterfat diet supplemented with none (C), 5% of bitter ground powder (BGP), 1% EA extract (EAE) or 3% ethanol extract (E) of bitter ground powder, 1% clofibrate (CF) or 0.01% rosiglitazone (R) for 5 weeks. Hyperinsulinemia and glucose intolerance were observed in the C group but not in the BGP, CF and R groups. Serum insulin of the EAE and E groups were also significantly lower than that of the C group. Up-regulation of PPARα target gene (ACO) mRNA expression were observed in rats fed the test diets containing 5% bitter ground powder (BGP) and 1% bitter ground powder EA extract (EAE). In conclusion, 5% wild bitter ground powder improved high fat diet-induced metabolic syndrome, such as hyperglycemia, hyperlipidemia, and glucose intolerance. These results provide evidence that wild bitter melon may potentially be developed as a functional food for ameliorating hyperglycemia and hyperlipidemia.

1. 鄒尚瑀(2016)。長期餵食山苦瓜對高脂飲食誘導肥胖小鼠代謝異常及白色脂肪組織褐化相關基因表現之效應。臺灣大學生化科技學系學位論文。2016。1-103。 
2. 董又慈(2016)。山苦瓜改善高脂飲食誘發小鼠代謝異常、脂肪肝與肝相關基因 mRNA 表現。臺灣大學生化科技學系學位論文。2016。1-101。