Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou 450009, China.
Molecules. 2023 Jul 7;28(13):5265. doi: 10.3390/molecules28135265.
Epigallocatechin gallate (EGCG) and kaempferol exhibit cellular antioxidant activity; however, their interactive effects in terms of antioxidant actions and underlying mechanisms remain unclear. In this study, their cytoprotective effects were examined against 2,2-azobis (2-amidinopropane) dihydrochloride solution (ABAP)-induced oxidative stress in HepG2 cells. The results showed that the median effective dose (EC) of the EGCG and kaempferol (6:1.5, c/c) combination was 3.4 ± 0.1 μg/mL, with a combination index (CI) value of 0.54, which represented a significant synergistic effect. Further experiments proved that the combined pretreatment with EGCG and kaempferol exerted protective effects by suppressing reactive oxygen species (ROS) generation, upregulating cellular antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px)) in a dose-dependent manner. The mechanism of synergistic antioxidant effects of EGCG combined with kaempferol may be due to the up-regulation of higher antioxidant enzyme activities that improve the antioxidant capacities and balance the cell oxidative stress. The synergistic antioxidant effect of EGCG and kaempferol can provide a theoretical basis for the development of formulas of functional food ingredients.
没食子酸表没食子儿茶素酯 (EGCG) 和山柰酚具有细胞抗氧化活性; 然而，它们在抗氧化作用及其潜在机制方面的相互作用尚不清楚。本研究考察了 EGCG 和山柰酚（6:1.5，c/c）混合物对 2,2-偶氮双（2-脒基丙烷）二盐酸盐（ABAP）溶液诱导的 HepG2 细胞氧化应激的细胞保护作用。结果表明，EGCG 和山柰酚（6:1.5，c/c）混合物的半数有效剂量（EC）为 3.4 ± 0.1 μg/mL，合并指数（CI）值为 0.54，表现出显著的协同作用。进一步的实验证明，EGCG 和山柰酚联合预处理通过抑制活性氧（ROS）的产生，以剂量依赖性方式上调细胞抗氧化酶活性（超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和谷胱甘肽过氧化物酶（GSH-Px））发挥保护作用。EGCG 与山柰酚协同抗氧化作用的机制可能是由于上调更高的抗氧化酶活性，从而提高抗氧化能力并平衡细胞氧化应激。EGCG 和山柰酚的协同抗氧化作用可为功能性食品成分配方的开发提供理论依据。
