L-茶氨酸改善热应激引起的小鼠组织损伤和氧化逆境

摘要

以SPF级Slca/KM雄性小鼠作为实验对象,在恒温恒湿模拟气候箱进行热处理,灌喂干预不同剂量L-茶氨酸,考察L-茶氨酸对小鼠采食量、体重变化、空肠切片病理情况、器官指数、血清谷丙转氨酶(ALT)与谷草转氨酶(AST)活性、血清肿瘤坏死因子(TNF-α)、白细胞介素6(IL-6)和干扰素-γ(IFN-γ)含量、肝组织丙二醛(MDA)含量、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)活性以及肝组织病理学变化的影响,以探讨L-茶氨酸改善热处理引起的小鼠组织损伤和氧化逆境作用.结果表明,L-茶氨酸能在一定程度上促进热处理小鼠采食量和体重的增加,降低肝脏和脾脏器官指数,降低血清ALT、AST酶活性,抑制血清炎症介质TNF-α、IL-6、IFN-γ 的含量,降低肝组织MDA含量,提高SOD、GSH-Px、CAT酶活性,减轻热处理对空肠及肝脏组织的损伤,且以L-茶氨酸中剂量处理效果较好.说明L-茶氨酸具有改善热处理引起的小鼠组织损伤和氧化逆境的作用,主要表现为提高小鼠营养物质吸收能力、减少炎性细胞因子表达,以及降低氧化损伤.%The effects of different dosages of L-theanine on SPF grade Balb/KM male mice under heat treatment, including feed intake, weight, organs index, histopathological features of jejunum, activities of serum alanine aminotranferease (ALT) and aspartate aminotransferase (AST), contents of tumor necrosis factor (TNF-α), interleukin-6 (IL-6), interferon-γ (IFN-γ) in serum, content of liver homogenate malondialdehyde (MDA), activities of liver homogenate superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and histopathological features of liver tissue were studied. Results showed that pretreatment with different dosages of L-theanine increased the feed intake and body weight of the mice, enhanced the activities of liver homogenate SOD, CAT, GSH-Px, decreased the index of liver and spleen, damages in the jejunum, activities of serum ALT, AST, contents of TNF-α, IL-6 and IFN-γ in serum, content of liver homogenate MDA and attenuated the damages of liver by heat treatment. The best attenuating effect of L-theanine on damages was under middle dosage treatment. It suggests that L-theanine mainly improves the absorptive capacity, reduces the expressions of inflammatory cytokines and oxidative damage in mice, which finally attenuate the tissue and oxidative damages caused by heat stress.