訶子之抗氧化活性成分保護PC12細胞對抗巴拉刈之毒性

The Anti-oxidative Components of Terminalia Chebula Protect PC12 Cells against Paraquatinduced Toxicity

"背景：PC12 cell line乃源自大鼠腎上腺髓質嗜鉻細胞瘤之細胞株，可作為多巴胺源神經元（dopaminergic neurons）的研究模型，用於探索巴拉刈毒性及神經保護劑的體外研究模型之開發。材料與方法：本研究主要是探討訶子95％乙醇萃取物的分層萃取物（正己烷萃取物、二氯甲烷萃取物、乙酸乙酯萃取物及水萃取物）抑制巴拉刈毒性而保護PC12細胞之作用，以及分析訶子95％乙醇萃取物的分層萃取物之總酚、總類黃酮、總單寧與粗三萜成分含量及清除2-對-1,1-二苯基苦基苯肼（DPPH）自由基、過氧化氫、氫氧根離子自由基與超氧陰離子的抗氧化作用。結果：水萃取物的總酚成分含量最高，二氯甲烷萃取物中總類黃酮、總單寧及粗三萜成分含量最高。抗氧化作用是乙酸乙酯萃取物對DPPH自由基、過氧化氫、氫氧根離子自由基與超氧陰離子的清除效果最佳，而且乙酸乙酯萃取物抑制巴拉刈毒性而保護PC12細胞的能力最佳。結論：訶子95％乙醇萃取物的乙酸乙酯萃取物抗氧化效力最佳能抑制巴拉刈毒性而保護PC12細胞，希望訶子成分將來能成為神經保護劑。"

Background: PC12 cell line is a rat adrenal medullary pheochromocytoma cell line, which has been used as a model to conduct studies on dopaminergic neurons to explore paraquat toxicity. Additionally, it has been used to develop an in vitro research model for the development of neuroprotective agents. Materials and methods: In this study, we mainly investigated the layered extracts (n-hexane, dichloromethane, ethyl acetate, and water extracts) of the 95 % ethanol extract of Terminalia chebula for inhibiting the toxicity effect of paraquat to protect the PC12 cells. Further, we analyzed the total phenol, flavonoid, tannin, and triterpene contents of the aforementioned layered extracts. The antioxidant effects that were assessed included the scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, hydrogen peroxide, hydroxyl radicals, and superoxide anions. Results: The water extract was found to possess the highest content of total phenolic compounds, while the dichloromethane extract possessed the highest contents of total flavonoid, tannin, and triterpene. The highest antioxidant effect of scavenging the DPPH radicals, hydrogen peroxide, hydroxyl radicals, and superoxide anions was exhibited by the ethyl acetate extract, and it was most efficient in inhibiting paraquat toxicity and protecting the PC12 cells. Conclusion: The ethyl acetate extract of the 95 % ethanol extract of T. chebula exhibited the most effective antioxidant effect among all the tested extracts in inhibiting paraquat toxicity and protecting PC12 cells. It is thus believed that the T. chebula composition can be utilized as a potential neuroprotective agent in the future.