Liu Dongmei, Zhang Xiaoli, Jiang Li, Guo Yun, Zheng Changqing
Department of Rheumatology and Immunology, Shengjing Hospital, China Medical University, Shenyang 110004, People's Republic of China.
Department of Gastroenterology, Shengjing Hospital, China Medical University, Shenyang 110004, People's Republic of China.
Acta Histochem. 2014 May;116(4):654-62. doi: 10.1016/j.acthis.2013.12.002. Epub 2013 Dec 26.
(-)-Epigallocatechin-3-gallate (EGCG) is the most abundant polyphenolic compound present in green tea and has been shown to possess anti-inflammatory and anti-oxidative properties. In this study, we investigated the protective effects of EGCG against concanavalin A (ConA)-induced liver injury and the underlying mechanisms. EGCG (5 mg/kg) was administered orally by gavage to mice twice daily for 10 days before an intravenous injection of ConA. We found that EGCG effectively rescued lethality, improved hepatic pathological damage, and decreased serum levels of alanine aminotransaminase (ALT) in ConA-challenged mice. Furthermore, EGCG also significantly prevented the release of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-4, and IL-6 in serum, reduced malondialdehyde (MDA) levels, and restored glutathione (GSH) content and superoxide dismutase (SOD) activity in liver tissues from ConA-challenged mice. Finally, nuclear factor (NF)-κB activation and expression levels of Toll-like receptor (TLR) 2, TLR4 and TLR9 protein in liver tissues were significantly inhibited by EGCG pretreatment. Taken together, our data suggest that EGCG possesses hepatoprotective properties against ConA-induced liver injury through its anti-inflammatory and anti-oxidant actions.
(-)-表没食子儿茶素-3-没食子酸酯(EGCG)是绿茶中含量最丰富的多酚类化合物,已被证明具有抗炎和抗氧化特性。在本研究中,我们研究了EGCG对刀豆蛋白A(ConA)诱导的肝损伤的保护作用及其潜在机制。在静脉注射ConA前10天,每天两次给小鼠经口灌胃给予EGCG(5mg/kg)。我们发现EGCG有效挽救了ConA攻击小鼠的致死率,改善了肝脏病理损伤,并降低了血清丙氨酸氨基转移酶(ALT)水平。此外,EGCG还显著抑制了血清中肿瘤坏死因子(TNF)-α、干扰素(IFN)-γ、白细胞介素(IL)-4和IL-6的释放,降低了丙二醛(MDA)水平,并恢复了ConA攻击小鼠肝脏组织中的谷胱甘肽(GSH)含量和超氧化物歧化酶(SOD)活性。最后,EGCG预处理显著抑制了肝脏组织中核因子(NF)-κB的激活以及Toll样受体(TLR)2、TLR4和TLR9蛋白的表达水平。综上所述,我们的数据表明EGCG通过其抗炎和抗氧化作用对ConA诱导的肝损伤具有肝保护特性。