白甘藷西蒙一號乙酸乙酯萃取物對倉鼠脂質代謝的影響

Effects of white sweet potato Simon No. 1 ethyl acetate extract on lipid metabolism in hamsters

李威(Wei Lee)

指導教授 ： 施純光

臺北醫學大學/公共衛生暨營養學院/保健營養學研究所/碩士(2015年)

摘要

高血脂症為與肥胖相關的全球性健康議題，其中血清低密度脂蛋白膽固醇過高會導致動脈粥狀硬化進而引發高血壓等心血管疾病。白甘藷為部分亞洲國家所使用的傳統民間用藥，有研究指出其具有改善胰島素抗性及調節膽固醇濃度的效果，然而白甘藷調節膽固醇代謝的機制尚未釐清，因此本次研究目的為觀察白甘藷西蒙一號乙酸乙酯萃取物對於倉鼠脂質代謝的影響。將倉鼠分為四組並飼養八週，其分組如下：正常組 (N)，餵食AIN-93G 標準飲食；控制組 (C)，餵食以AIN-93G 飼料為基礎調整之高油 (20%)高膽固醇 (0.2%)飲食；低劑量組 (L)，控制組飲食添加每公斤
飼料0.6 克白甘藷西蒙一號乙酸乙酯萃取物；高劑量組 (H)，控制組飲食添加每公斤飼料1.9 克白甘藷西蒙一號乙酸乙酯萃取物。結果顯示低劑量組血清低密度脂蛋白膽固醇濃度顯著低於控制組，而糞便膽酸濃度則高於控制組。高劑量組血清低密度脂蛋白膽固醇濃度及糞便膽酸濃度與低劑量組或控制組皆無統計差異。此外，低劑量組肝臟低密度脂蛋白受器蛋白質表現量顯著高於控制組，可能為血清低密度脂蛋白膽固醇濃度較低的原因。各組間血清三酸甘油酯與高密度脂蛋白膽固醇濃度皆無統計差異。本研究結果顯示白甘藷西蒙一號乙酸乙酯萃取物可能透過調控肝臟低密度脂蛋白的吸收並增加糞便中膽酸的排除，達到降低血清低密度脂蛋白膽固醇濃度的效果。

關鍵字

白甘藷 ； 膽固醇 ； 膽酸 ； 低密度脂蛋白受器 ； 倉鼠

並列摘要

Hyperlipidemia is a world-wild health issue which is associated with obesity. High concentration of serum low-density lipoprotein cholesterol (LDL-C) will lead to atherosclerosis which might cause cardiovascular disease (CVD) such as hypertension. White sweet potato, a traditional medicine in some Asian countries, has been shown to be beneficial in regulating insulin resistance and total cholesterol concentration. However, the mechanism of cholesterol-regulating effects of white sweet potato Simon No. 1 had seldom been studied before. In the present study, hamsters were grouped as ollowings: normal group (N) fed standard AIN-93G diet, control (C) group fed modified AIN-93G diet containing high (20%) fat and high (0.2%) cholesterol, low-dose group (L) fed control diet containing 0.6 g/kg of white sweet potato Simon No. 1 ethyl acetate (EA) extract and high-dose group (H) fed control diet containing 1.9 g/kg of white sweet potato Simon No. 1 EA extract. All animals were fed ad libitum for eight weeks. Results showed that low-dose group had significantly lower concentration of serum LDL-C and higher concentration of fecal bile acid than control group. High-dose group showed no significant difference in serum LDL-C and fecal bile acid concentrations from low-dose and control groups. In addition, low-dose group had higher liver LDL-receptor protein expression than control group which may cause the serum LDL-C-lowering effect. Serum triglycerides and high-density lipoprotein cholesterol (HDL-C) concentrations were not different among groups. These findings suggest that white sweet potato Simon No. 1 EA extract may reduce LDL-C in hamsters by increasing hepatic LDL uptake and fecal bile acid excretion.

並列關鍵字

White sweet potato ； Cholesterol ； Bile acid ； Low-density lipoprotein-receptor ； Hamster

參考文獻

Ahmadian M, Suh JM, Hah N, Liddle C, Atkins AR, Downes M, Evans RM (2013)

PPARγ signaling and metabolism: the good, the bad and the future. Nat Med 19:557-566.

Alves Cde A, Lima DS (2008) Cystic fibrosis-related dyslipidemia. J Bras Pneumol

34:829-837.

Arantes PR, Sachett LG, Graebin CS, Verli H (2014) Conformational characterization of