利用中草藥降低脂肪細胞胰島素抗阻性之研究

3T3-L1 signal transduction affected by two herbal extract.

王怡(Yi Wang)

指導教授 ： 李孟真

朝陽科技大學/理工學院/生化科技研究所/碩士(2011年)

摘要

台灣原生種土肉桂與苦瓜在傳統中草藥兩種植株皆具有降低血糖及治療糖尿病的效果。先前實驗已指出，土肉桂葉分離出之純物質具有類胰島素之功效，本論文研究方向主要是探討A. 土肉桂水萃物是否具有活化胰島素訊息傳遞的活性，及在水萃物中未知物質及三種山奈苷 (kaempferitrin) 的衍生物CO-1、CO-2、CO-3之間的交互作用是否影響活性。B. 苦瓜萃取物是否有活化胰島素訊息傳遞的活性。方法為培養3T3-L1脂肪細胞分化8天，加入胰島素或水萃物，進行western blot。結果顯示水萃物稀釋1, 2, 15倍，可增加胰島素受體的自體酪胺酸磷酸化，稀釋2, 5, 10倍，可增加Akt的酪胺酸磷酸化。水萃物稀釋1, 2, 5, 10, 15倍，在脂肪細胞皆可刺激分泌脂締素 (Adiponectin) 分泌的效果。此實驗顯示土肉桂水萃物具有降低胰島素抗阻性和有類胰島素的功效。此外，本實驗結果並未顯示水萃物中的純物質活性具有加乘效果。有可能是藥物對訊息傳遞已經達到極限，或者是水萃物中的未知物質會抑制活化。另外，苦瓜粗萃取物於3T3-L1前脂肪細胞的分化培養液添加苦瓜粗萃取物，進行分化及Oil red O染色，並利用顯微鏡拍照，數脂肪滴顆數定量且比較，測試粗萃物是否具有類胰島素之效果。由實驗結果顯示1~6號樣品與2-1~2-4號樣品，都可以使增加脂肪生成，並且5號樣品 (10-1 mg/mL) 和6號樣品 (1 mg/mL) 脂肪生成率較佳。此外，5號樣品濃度10-1 mg/mL和6號樣品 (DMSO) 濃度1 mg/mL以及6號樣品(H2O) 濃度10-4 mg/mL，可促進胰島素受體的自體酪胺酸磷酸化；5號樣品濃度10-1 mg/mL和6號樣品 (H2O) 濃度10-1 mg/mL，可增加Akt的酪胺酸磷酸化。本實驗結果顯示苦瓜具有類胰島素的活性。

關鍵字

台灣原生種土肉桂 ； 苦瓜 ； 胰島素抗阻性 ； 胰島素傳遞路徑

並列摘要

Cinnamomum osmophloeum Kaneh and Momordica charantia have been used as a traditional chinese herb medicine. They were believed to hypoglycemic and heal diabetes. The main purpose of this research was to A. explore activities of the water extraction of Cinnamomum osmophloeum leaves, which includes activation of insulin signaling pathways, and whether the unknown substances and 3 kinds of kaempferol glycosides derivatives CO-1, CO-2 and CO-3 interfere with each other for the signaling pathways. B. To evaluate whether the extract from Momordica charantia could activate insulin signaling pathway. The 3T3-L1 were differentiated for eight day, followed by addition of water extract, and western blotting performed. The water extract, significantly stimulated tyrosine phosphorylation of IRβ at 1, 2, 15 fold dilution. It also increase the tyrosine phosphorylation of Akt at dilution at 2, 5, 10 fold. The water extract stimulated adiponectin secretion in 3T3-L1 adipose cells at dilution of 1, 2, 5, 10, and 15 fold. The data showed that water extract has reduced insulin resistance and insulin mimicking effects. In addition, the results showed that the 3 single compounds in water extract did not work synergistically, possibly due to pleateu effect, or water extract contain unknown substances that inhibit the activation. The effect of bitter melon extract on the differentiation of 3T3-L1 preadipocytes was tested by its effect to stimulate oil drop production. The results indicate that No 1~6 sample and No 2-1~2-4 sample increase the lipogenesis. The No 5 sample (10-1 mg/mL) and No 6 sample (1 mg/mL) have the best lipogenesis rate. No 5 sample (10-1 mg/mL) and No 6 sample (DMSO) 10-4 mg/mL stimulated tyrosine phosphorylation of IRβ, and 10-1 mg/mL of No 5 sample and 10-4 mg/mL of No 6 sample (H2O) increased the tyrosine phosphorylation of Akt. The data showed that bitter melon extract has insulin mimicking effect.

並列關鍵字

Cinnamomum osmophloeum ； Momordica charantia ； insulin resistance ； insulin signaling pathways

參考文獻

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