山奈苷神經保護功效之研究

Neuroprotective Effect of the Kaempferitrin on PC 12 Cells

盧怡如(Yi-Ju Lu)

指導教授 ： 李孟真

朝陽科技大學/理工學院/應用化學系生化科技碩博士班/碩士(2014年)

摘要

Kaempferitrin 是一種可以從幾種植物中分離出的類黃酮糖苷 (glycoside flavonoids) 具有抗細菌、鎮痛以及抗發炎等功效。本實驗室先前的實驗中發現土肉桂中所分離出的 Kaempferitrin 可以活化前脂肪細胞 (3T3-L1) 中的胰島素路徑來刺激葡萄糖轉運子位移到細胞膜表面來幫助葡萄糖的運輸，而胰島素抗阻性 (insulin resistance) 已被證實與神經退化性疾病阿茲海默症 (Alzheimer’s disease) 具有高度相關性。有文獻指出在嗜鉻性細胞瘤細胞株 (PC12) 細胞中，胰島素可以預防無血清所造成的細胞死亡。因此，本研究主要探討在無血清環境下 Kaempferitrin 對 PC12 細胞是否有保護的作用以及 Kaempferitrin 是經由影響哪種存活路徑來保護細胞免於死亡。經由 XTT assay，我們發現 Kaempferitrin 不管是在無血清或血清飢餓 (含 0.2 % FBS) 培養基中都能夠提高 PC12 細胞的生存率。另外在 Western blot 中我們也發現到 Kaempferitrin 可以降低 cleaved caspase 3 的表現量，而 Kaempferitrin 還影響那些細胞存活路徑還需要近一步研究與確認。

關鍵字

胰島素抗阻性 ； 山奈苷 ； 台灣原生種土肉桂 ； 胰島素傳遞路徑 ； 神經保護

並列摘要

Kaempferitrin was previously shown to activates insulin transduction pathway in differentiated 3T3-L1 cells with mature adipocyte phenotypes. Oral administration of Kaempferitrin induced a significant hypoglycemic effect in diabetic rats and antioxidative activity. Furthermore, Kaempferitrin has shown antinociceptive and anti-inflammatory effect. Insulin activate receptor tyrosine kinase and downstream pathway to promote GLUT4 translocation and glucose uptake in adipocyte, and insulin resistance has been shown to be a potential factor contributing to Alzheimer's disease. Therefore we would like to test if Kaempferitrin activate insulin signaling pathway in PC12 cells, a cell line of neural origin, and if it protect this cell from cell death . PC12 cells dies in serum free medium, while addition of insulin to serum-free medium results in survival and proliferate for over a week via activation of insulin pathway. To determine the action of Kaempferitrin, PC12 cells were incubate in serum-starved or serum-free medium containing Kaempferitrin. Cell viability were measured by XTT assay and detect cleaved caspase-3 by Western blot assay. Our results suggested that Kaempferitrin rescued serum starvation and serum-free induced PC12 cells death. Kaempferitrin also reduced cleaved caspase-3, an apoptosis marker, at certain concentration. The mechanisms of Kaempferitrin against serum starvation or serum-free medium induce cell death remain to be explored.

並列關鍵字

insulin resistance ； Kaempferitrin ； Cinnamomoum osmophloeum ； insulin pathway ； neuroprotection

參考文獻

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