Thitimuta Surached, Pithayanukul Pimolpan, Nithitanakool Saruth, Bavovada Rapepol, Leanpolchareanchai Jiraporn, Saparpakorn Patchreenart
Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok 10400, Thailand.
Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand.
Molecules. 2017 Mar 4;22(3):401. doi: 10.3390/molecules22030401.
The aims of this study were to investigate the potential benefits of antioxidant, anti-inflammatory, anti-hepatotoxic, and anti-tyrosinase activities of a methanolic extract of fresh tea leaves (FTE) ( L.). The antioxidant capacity was investigated using three different methods at different temperatures. The anti-inflammatory activity was studied in vitro by the inhibition of 5-lipoxygenase assay. The anti-hepatotoxic effect was investigated in CCl₄-induced liver injury in rats. The anti-tyrosinase activities of the FTE and its principal phenolic compounds were investigated in l-3,4-dihydroxyphenylalanine (l-DOPA) oxidation by a mushroom tyrosinase. A molecular docking study was conducted to determine how the FTE's principal catechins interact with the tyrosinase. The FTE exhibited the best shelf life at low temperatures and demonstrated concentration-dependent antioxidant, anti-inflammatory, anti-hepatotoxic, and anti-tyrosinase effects compared to positive references. Treatment of rats with the FTE at 2000 mg/kg/day for 28 consecutive days reversed CCl₄-induced oxidative damage in hepatic tissues by lowering the levels of alanine aminotransferase by 69% and malondialdehyde by 90%. Our findings suggest that the FTE has the capacity to scavenge free radicals and can protect against oxidative stress induced by CCl₄ intoxication. The docking results were consistent with our in vitro data, indicating the anti-tyrosinase potency of the principal catechins.
本研究的目的是探究新鲜茶叶(FTE)(L.)甲醇提取物的抗氧化、抗炎、抗肝毒性和抗酪氨酸酶活性的潜在益处。在不同温度下使用三种不同方法研究抗氧化能力。通过抑制5-脂氧合酶测定法体外研究抗炎活性。在四氯化碳诱导的大鼠肝损伤中研究抗肝毒性作用。通过蘑菇酪氨酸酶对L-3,4-二羟基苯丙氨酸(L-DOPA)氧化研究FTE及其主要酚类化合物的抗酪氨酸酶活性。进行分子对接研究以确定FTE的主要儿茶素如何与酪氨酸酶相互作用。FTE在低温下表现出最佳保质期,与阳性对照相比,表现出浓度依赖性的抗氧化、抗炎、抗肝毒性和抗酪氨酸酶作用。以2000 mg/kg/天的剂量连续28天用FTE处理大鼠,可使肝组织中四氯化碳诱导的氧化损伤得到逆转,丙氨酸转氨酶水平降低69%,丙二醛水平降低90%。我们的研究结果表明,FTE具有清除自由基的能力,可预防四氯化碳中毒诱导的氧化应激。对接结果与我们的体外数据一致,表明主要儿茶素具有抗酪氨酸酶效力。