分析石蓮花調控肝細胞之代謝變異

Analysis of Graptopetalum paraguayense regulate metabolic variation in the hepatocytes

劉文煥(Wen-Huan Liu)

指導教授 ： 王逢盛

國立中正大學/工學院/化學工程學系/碩士(2015年)

摘要

肝臟是人體內最大的器官，其功能以代謝為主，其中肝細胞(Hepatocyte) 在身體裡面扮演著去除毒素、儲存醣原（肝醣）和分泌性蛋白質合成等重要生理機制，為人體重要的代謝器官；許多肝疾病病患都會有黃疸的症狀，是由於肝細胞受損、破裂導致膽紅素大量排出，累積在肝臟中所致。本研究利用人類肝細胞代謝網路模型Recon2 liver model，於肝細胞攝取營養基質(醣類、胺基酸、維生素) 並執行膽紅素(Bilirubin)排出等生理功能，使用通量平衡分析方法(Flux balance analysis, FBA)模擬人類肝細胞在合成ATP最佳化通量下得到穩態通量分佈。之後我們剔除腫瘤抑制基因miR122，得到通量改變後的穩態通量分佈，與正常肝細胞進行比較，發現CYP7A1和GLS其對應之酵素高度表現會造成肝細胞受損最為嚴重，接著我們比對人類與老鼠共同具有之miR122 target gene，觀察到兩者沃伯格類似率的相似度極高，證明本模型可以用於模擬人類與老鼠。石蓮花(Graptopetalum paraguayense, GP)為傳統中藥材，已被認為有治療肝功能受損、降低血壓和抑制發炎症狀。陽明大學黃奇英教授團隊研究論文曾提到石蓮花具有抑制PGC-1α共激活因子的功能，而PGC-1α具有活化醣新生與脂質生成的作用。我們在12種miR122 target gene (ABHD2、ADPRM、B3GALNT1、CYP7A1、GALNT1、GALNT10、GALNT3、GYS1、LIPH、PTPDC1、RFK、TYMS)失常時，利用石蓮花所調控之反應通量，調控人體肝細胞代謝通量變化，其結果有趨向於回復接近正常狀態。

關鍵字

miR122 ； 肝細胞代謝網絡 ； 最適化模擬 ； 沃伯格效應

並列摘要

Liver is the largest organ with the main metabolic functions in human body. The hepatocyte inside the body play a role of important physiological mechanism, including getting rid of the toxin, storage of glycogen and synthesis of protein. Many patients with liver disease had symptoms of jaundice. Due to liver cell damage, a lot of bilirubin discharge and accumulate in the liver. In this study, we used the human metabolic network model of Recon2 liver model to simulate bilirubin metabolic functions and uptake of nutrient substrates (carbohydrates, amino acids, vitamins) and other physiological functions. Then we applied flux balance analysis (FBA) to simulate human liver metabolism under steady-state flux distribution in the maximize ATP synthesis. After deletion of tumor suppressor genes miR122,. we found overexpression of CYP7A1 and GLS would cause the most serious damage of liver cells, compared with normal condition. Then we compared with identical miR122 target genes in human and mouse , we found similarity ratio of Warburg effect between human and mouse is very similar. Therefore, we confirmed the model that can be use to simulate metabolic network of human and mouse. Graptopetalum paraguayense(GP), a traditional Chinese herbal medicine, exhibits beneficial effects on hypertension, hyperuricemia, inflammation, and chronic liver diseases. Professor C.Y Huang has mentioned GP could inhibit coactivator PGC-1α, and PGC-1α correlates with the activation of gluconeogenesis and lipogenesis.We overexpressed 12 miR122 target gene(ABHD2、ADPRM、B3GALNT1、CYP7A1、GALNT1、GALNT10、GALNT3、GYS1、LIPH、PTPDC1、RFK、TYMS) and down-regulated reactions by GP regulation. As the result, the metabolic flux distribution reprogrammed , and the damage cell treated with GP could be restored to close to normal liver cell state.

並列關鍵字

Warburg effect ； liver-specific metabolic networks ； Optimization ； miR122

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