苦瓜萃取物再分劃對胰島素阻抗鼠改善之影響

Further studies on improving insulin resistance effects of Momordica charantia extract fraction in mice

蕭民宗(Min-zong Hsiao)

指導教授 ： 施純青

中臺科技大學/健康科學院/藥物科技研究所/碩士(2010年)

摘要

苦瓜(Momordica charantia Linn)是葫蘆科(Cucurbitacrae)苦瓜的果實，為我國民間常食用蔬菜，當作一降血糖藥。實驗性動物模式顯示短期灌食苦瓜汁或其種子的粉末可降低空腹血糖濃度並改善糖耐量。之前的研究顯示苦瓜具有減弱胰島素阻抗現象。儘管如此，再分劃萃取物之於改善胰島素阻抗作用機轉尚未研究透徹，試圖找出有效無毒分層的活性成分。所以我們採用高脂肪餵食動物模式以探測苦瓜再分層之作用。此實驗持續12週，首先將C57/BL6J小鼠隨意分成兩組，對照組餵以對照飼料，而實驗組再次分為五組和餵以高脂肪飼料(High Fat Diet)八週，而後經口投與苦瓜氯仿再分劃萃取物或蒸餾水四週。經過十二週的誘導之後，進行犧牲。在這期間，會將小鼠抽血，並進行生化值的檢測，以及犧牲後，會取下小鼠的脂肪組織、肝臟及骨骼肌。結果顯示給予苦瓜萃取物顯著降低高脂肪飲食造成體重的增加，和顯著降低高脂飲食所造成的內臟脂肪重量的增加(P < 0.05 respectively)。投與苦瓜萃取物顯著逆轉高脂肪飲食所導致的高血糖血症、高胰島素血症、高瘦體素血症、和高游離脂肪酸濃度等現象。給予苦瓜後會影響白色脂肪組織PPARγ mRNA、及肝臟PPARα mRNA及骨骼肌GLUT4 mRNA表現。

這些結果建議苦瓜氯仿再分劃可改善小鼠的高脂肪飲食所引起的胰島素阻抗現象。

關鍵字

苦瓜 ； 胰島素阻抗 ； 高血糖血症 ； GLUT4

並列摘要

Momordica charantia Linn. (Cucurbitaceae), also is referred to as bitter melon, and has been used as a traditional anti-diabetic remedy for many years in countries such as China (Karunanayake and Tennekoon, 1993). The efficacy of bitter melon has also been reported in a number of animal studies, although many of them used Type 1 diabetes model (Akhtar et al., 1981; Srivastava et al., 1987; Day et al., 1990; Pugazhenthi and Murthy, 1995). Results from most recent study (Shih et al, 2008, 2009)indicated that bitter melon was effective in ameliorating the high-fat and high-fructose diet-induced insulin resistance. Despite its long history as an edible and medicinal fruit, limited data are available on the active constituents and consequently the amelioration of insulin resistance.
The effect of chloroform fractional extract of Momordica charantia (bitter melon) fruits on insulin resistance was examines in mice fed with a high-fat (HF) diet. First, the mice were divided randomly into two groups: the control (CON) group was fed with a low-fat diet, whereas the experimental group was fed with a HF diet for 12 weeks. After 8 weeks of induction, the HF group was subdivided into five groups and was given orally bitter melon extract or not 4 weeks afterward.
It was demonstrated that bitter melon was effective in ameliorating the HF diet-induced hyperglycemia, hyperleptinemia, hyperinsulinemia and hypertriglycemia as well as affecting the adipose PPARγ and hepatic PPARα mRNA levels. Bitter melon significantly decreased the body weight gain, weights of visceral fat (P <0.05, respectively) accompanying the affected adipose leptin and skeletal muscle glucose transporter 4 (GLUT4) mRNA
The findings provide a nutritional basis for the use of bitter melon as a functional food factor that may have benefits for the improvement of insulin resistance

並列關鍵字

Momordica charantia ； insulin resistance ； hypergl

參考文獻

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