Han Xiao-Dong, Zhang Yan-Yan, Wang Ke-Lei, Huang Yong-Pan, Yang Zhong-Bao, Liu Zhi
Department of Anesthesia, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
Medical College, Yan'an University, Yan'an, Shaanxi 716000, China.
Oncotarget. 2017 Jun 21;8(39):65302-65312. doi: 10.18632/oncotarget.18582. eCollection 2017 Sep 12.
Arsenic exposure produces hepatotoxicity. The common mechanism determining its toxicity is the generation of oxidative stress. Oxidative stress induced by arsenic leads to the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. (-)-Epigallocatechin-3-gallate (EGCG) possesses a potent antioxidant capacity and exhibits extensive pharmacological activities. This study aims to evaluate effects of EGCG on arsenic-induced hepatotoxicity and activation of Nrf2 pathway. Plasma activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase were measured; Histological analyses were conducted to observe morphological changes; Biochemical indexes such as oxidative stress (Catalase (CAT), malonyldialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), reactive oxygen species (ROS)), Nrf2 signaling related genes () were assessed. The results showed that EGCG inhibited arsenic-induced hepatic pathological damage, liver ROS level and MDA level. Arsenic decreases the antioxidant enzymes SOD, GPX, and CAT activity and the decrease was inhibited by treatment of EGCG. Furthermore, EGCG attenuated the retention of arsenic in liver tissues and improved the expressions of Nrf2 signaling related genes (). These findings provide evidences that EGCG may be useful for reducing hepatotoxicity associated with oxidative stress by the activation of Nrf2 signaling pathway. Our findings suggest a possible mechanism of antioxidant EGCG in preventing hepatotoxicity, which implicate that EGCG may be a potential treatment for arsenicosis therapy.
砷暴露会产生肝毒性。决定其毒性的常见机制是氧化应激的产生。砷诱导的氧化应激会导致核因子红细胞2相关因子2(Nrf2)信号通路的激活。(-)-表没食子儿茶素-3-没食子酸酯(EGCG)具有强大的抗氧化能力,并展现出广泛的药理活性。本研究旨在评估EGCG对砷诱导的肝毒性及Nrf2信号通路激活的影响。检测了血浆中丙氨酸氨基转移酶、天冬氨酸氨基转移酶、碱性磷酸酶和乳酸脱氢酶的活性;进行组织学分析以观察形态学变化;评估了氧化应激(过氧化氢酶(CAT)、丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽(GSH)、活性氧(ROS))、Nrf2信号相关基因等生化指标。结果表明,EGCG抑制了砷诱导的肝脏病理损伤、肝脏ROS水平和MDA水平。砷降低了抗氧化酶SOD、GPX和CAT的活性,而EGCG处理可抑制这种降低。此外,EGCG减轻了肝脏组织中砷的潴留,并改善了Nrf2信号相关基因的表达。这些发现提供了证据,表明EGCG可能通过激活Nrf2信号通路来减轻与氧化应激相关的肝毒性。我们的研究结果提示了抗氧化剂EGCG预防肝毒性的可能机制,这意味着EGCG可能是治疗砷中毒的一种潜在疗法。