Chen Jiaqin, Wang Fei, Zhou Xin, Cao Yun, Li Yansen, Li Chunmei
College of Animal Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, PR China.
College of Animal Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, PR China.
J Therm Biol. 2017 Jul;67:15-21. doi: 10.1016/j.jtherbio.2017.04.012. Epub 2017 Apr 29.
The liver is one of the most crucial organs affected by high ambient temperature. Bama miniature pig show a heat tolerance in hot summer months. However, the physiological condition of liver under high ambient temperature has not been well elucidated in Bama miniature pig. Here we performed an experiment to investigate the effects of high ambient temperature on liver function, redox status and Nrf2 antioxidant pathway in Bama miniature pigs. Twelve pigs were randomly divided into two groups and separately exposed to the neutral temperature (NT, 25°C) and high temperature (HT, 40°C) for 8 days. The hepatic damage marker, such as total bilirubin (TBIL), alkaline phosphatase (AKP), γ-glutamyl transpeptidas (γ-GT), alanine transaminase (ALT) and aspartase transminase (AST), didn't reach statistical significance between NT and HT group. Moreover, abnormal observation of hepatic histology and hepatocyte ultrastructure were not detected in HT group. The activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) as well as glutathione (GSH) content, were dramatically increased after heat exposure. Heat treatment didn't increase hydrogen peroxide (HO) and malondialdehyde (MDA) concentrations. The expression of Nrf2-regulated genes, such as nuclear factor erythroid 2-related factor 2 (Nrf2), NAD(P)H: quinine oxidoreductase 1 (NQO1), superoxide dismutase 1 (SOD1), heme oxygenase-1 (HO-1) and glutamate cysteine ligase catalytic subunit (GCLC), were significantly increased in HT group. Nrf2 protein was accumulated in HT group through immunohistochemical analysis. The current data provide clear evidence that Bama miniature pigs' liver possess great capacity of heat tolerance, which related to activation of Nrf2 antioxidant pathway.
肝脏是受环境高温影响最关键的器官之一。巴马小型猪在炎热的夏季表现出耐热性。然而，高温环境下巴马小型猪肝脏的生理状况尚未得到充分阐明。在此，我们进行了一项实验，以研究环境高温对巴马小型猪肝功能、氧化还原状态和Nrf2抗氧化途径的影响。将12头猪随机分为两组，分别置于中性温度（NT，25°C）和高温（HT，40°C）环境中8天。肝脏损伤标志物，如总胆红素（TBIL）、碱性磷酸酶（AKP）、γ-谷氨酰转肽酶（γ-GT）、丙氨酸转氨酶（ALT）和天冬氨酸转氨酶（AST），在NT组和HT组之间未达到统计学显著差异。此外，HT组未检测到肝脏组织学和肝细胞超微结构的异常观察结果。热暴露后，超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）和过氧化氢酶（CAT）的活性以及谷胱甘肽（GSH）含量显著增加。热处理未增加过氧化氢（HO）和丙二醛（MDA）浓度。HT组中Nrf2调节基因，如核因子红细胞2相关因子2（Nrf2）、NAD（P）H：醌氧化还原酶1（NQO1）、超氧化物歧化酶1（SOD1）、血红素加氧酶-1（HO-1）和谷氨酸半胱氨酸连接酶催化亚基（GCLC）的表达显著增加。通过免疫组织化学分析，HT组中Nrf2蛋白积累。目前的数据提供了明确的证据，表明巴马小型猪的肝脏具有很强的耐热能力，这与Nrf2抗氧化途径的激活有关。
