食用桃金孃科植物萃取物減輕小鼠肝臟細胞 (FL83B) 胰島素阻抗之探討

Abstract

隨著生活水準不斷提高及醫療衛生的進步，國人平均壽命逐漸延長，慢性疾病遂成為威脅國人健康的重要禍因，其中糖尿病更是近年來罹患人數攀升最快的慢性疾病之一。番石榴屬桃金孃科植物(Myrtaceae plant)，已有許多文獻證實其具抗糖尿病之作用。本實驗以台灣常見之食用桃金孃科植物為材料，包括蓮霧、番石榴、蒲桃及肯氏蒲桃，篩選出具抗高血糖潛力之桃金孃科植物，再進一步對具調節血糖活性之物質進行分離、純化與結構鑑定。 實驗首先以食用桃金孃科植物生果及葉之水及乙醇萃出物分別進行小鼠肝臟 FL83B 細胞之細胞毒性 (Cell viability) 測試，以確定其安全使用劑量。再利用 TNF-α 誘導小鼠肝臟 FL83B 細胞株產生胰島素阻抗模式，以食用桃金孃科植物萃出物處理胰島素阻抗之肝臟細胞，評估其對提升細胞葡萄糖攝入能力及改善醣類代謝之效果。最後篩選出促進阻抗細胞葡萄糖攝入能力較佳的桃金孃科植物萃出物進行管柱層析，並進行降血糖活性物質之分離、純化。 由細胞毒性試驗結果發現，16 種食用桃金孃科植物水萃物於濃度 100μg/mL 時不具細胞毒性，而 16 種乙醇萃出物於低濃度(50μg/mL)下有 10 種不具毒性，但肯氏蒲桃葉子、帝王拔葉子、白拔生果及葉子萃出物具有較強的細胞毒性。胰島素阻抗細胞模式之葡萄糖攝入能力試驗，結果顯示，處理濃度 100μg/mL 時粉紅種蓮霧生果水萃物效果最好，與控制組( TNF-α處理)比較可增加 21% 的葡萄糖攝入能力，其次為肯氏蒲桃生果的水萃物及乙醇萃出物，分別提升了 18.32% 及 17.23%。由上述實驗結果，選取粉紅種蓮霧生果水萃物進行管柱層析，結果發現，經數次管柱流洗後之高極性區分物 fraction 1 於低濃度12.5 ug/mL下，與粉紅種蓮霧生果水萃物 100 ug/mL 有相近之提升胰島素阻抗肝臟細胞葡萄糖攝入之效果，推測其可能為粉紅種蓮霧生果水萃物主要降血糖之活性物質，目前正進行結構鑑定中。

As advanced medical technology and improved living standard increased life expectancy, chronic diseases have become a major threat to the health of people. Diabetes is one of the fastest growing chronic diseases. Guava (Psidium guajava Linn.) is belonged to the Myrtaceae plants and it has many references confirming its functions to alleviate diabetic symptoms. In this study, I will search others edible Myrtaceae plants in Taiwan, included Syzygium samarangense (Blume) Merrill et L.M. Perry, Psidium guajava Linn., Syzygium jambo(L.) Alston, Syzygium cumini Linn., screening extracts for potential of anti-hyperglycemic activity and search the active compound to enhance glucose uptake. First, Myrtaceae plants are extracted by different solvents (water and ethanol) to test the viability of the mouse liver cell FL83B. Safety dosage of the extracts of Myrtaceae plant is also evaluated. Secondly, the research will investigate the effect of the Myrtaceae plants extract (100μg/mL) on glucose uptake and evaluate on amelioration of carbohydrate metabolism in TNF-α-induced insulin resistant mouse liver FL83B cells. Finally, the best performing Myrtaceae plants to increase glucose uptake in the insulin resistant cell was analyzed by column chromatography, and the active components of the Myrtaceae plants which could decrease the blood sugar would be isolated and purified. Based on the results of cell viability test, majority of the Myrtaceae plants have no cell toxicity in concentration of 100μg/ml, and there were ten of ethanol extracts with no cell toxicity in a lower concentration (50μg/mL). Results of the glucose uptake ability in the insulin resistant cell modular indicated the group with the highest improvement is the water extract of unripe pink wax apple fruit. Compared with the control group (TNF-α treated group), the water extract of unripe pink wax apple fruit could increase the glucose uptake ability by 21%. Next is the water extract and the ethanol extract of unripe fruit of Syzygium cumini Linn., the percentage increase of the glucose uptake were 18.32% and 17.23% respectively. In conclusion, the water extracts of unripe wax apple fruit was collected for column chromatography. After several elutions, the high polarity fraction 1 at the concentration of 12.5μg/mL, had similar results as the water extract of unripe pink wax apple fruit at 100 μg/mL, in improving glucose uptake in the insulin resistant cell. The A partition was speculated to be the active component of the water extract of unripe pink wax apple fruit in decreasing blood sugar. The structure of the unknown extract is being identified.