SPF grade Balb/c female mice were used for this experiment. After adaptive feeding for 3 d, the mice were pre-treated orally with different dosages of L-theanine once daily for 30 d. ETEC E44813 intraperitoneal injection was subsequently performed and samples were collected 5h later. The coefficient of liver and spleen, levels of serum alanine aminotranferease (ALT), aspartate aminotransferase (AST) as well as liver homogenate malondialdehyde (MDA), and activities of liver homogenate superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), pathological changes of liver, expressions of serum γ-Interferon (IFN-γ) and Interleukin-4 (IL-4) were studied to explore the protective effects of L-theanine on liver of ETEC immune mouse model. Results show that pretreatment with L-theanine significantly reduced the increase of liver and spleen coefficient caused by ETEC infection|lowered the levels of serum ALT|AST and liver homogenate MDA|increased the activities of liver homogenate SOD|CAT|GSH-Px|decreased the expressions of serum IFN-γ|IL-4|and improved pathological injury of liver tissue. Therefore|it can be concluded that L-theanine is able to prevent ETEC-induced hepatic injury through depressing IFN-γ, IL-4 and inflammatory reaction and enhancing hepatocyte antioxidant abilities.
LIU Qiuling
,
GONG Zhihua
,
CHENG Ling
,
LIU Zunying
,
DENG Yanli
,
CHEN Dong
,
XIAO Wenjun
. Study on the Protective Effect of L-Theanine on the Liver of Mice with Immune Stress Induced by ETEC[J]. Journal of Tea Science, 2016
, 36(5)
: 484
-490
.
DOI: 10.13305/j.cnki.jts.2016.05.006
[1] 李中兴. 诊断细菌学[M]. 香港: 黄河文化出版社, 1992: 286-291.
[2] WHO IRIS.Future directions for research on enterotoxigenic Escherichia coli vaccines for developing countries[J]. Wkly Epidemiol Ree, 2006, 8l(11): 97-104.
[3] Qadri F, Svennerholm A M, Faruque A S, et al.Enterotoxigenic Escherichia coli in developing countries: epidemiology, microbiology, clinical features, treatment, and prevention[J]. Clin Micribiol Rev, 2005, 18(3): 465-483.
[4] 陈盼霖, 周明旭, 朱国强. 产肠毒素大肠杆菌研究进展和面临挑战[J]. 中国预防兽医学报, 2015, 37(10): 813-816.
[5] Qian Liu, Huiying Duan, Jinling Luan, et al.Effects of theanine on growth of human lung cancer and leukemia cells as well as migration and invasion of human lung cancer cells[J]. Cytotechnology, 2009, 59(3): 211-217.
[6] Zhang G, Miura Y, Yakasaki K.Effects of powdered green tea and theanine on tumor growth and endogenous hyperlipidemia in hepatoma-bearing rats[J]. Biosei Biotechnol Biochem, 2002, 66(4): 711-716.
[7] Sugiyama T, Sadzuka Y.Combination of theanine with doxorubicin inhibits hepatic metastasis of M5076 ovarian sarcoma[J]. Clinical Cancer Research, 1999, 5(5): 413-416.
[8] Sadzuka Y, Yamashita Y, Kishimoto S, et al.Glutamate transporter mediated increase of antitumor activity by theanine, an amino acid in green tea[J]. The Pharmaceutical Society of Japan, 2002, 122(11): 995-999.
[9] 雪玲, 程朝辉, 黄才欢, 等. 茶氨酸对小鼠学习记忆能力的影响[J]. 食品科学, 2004, 25(5): 171-173.
[10] 刘显明, 李月芬, 李国平. 茶氨酸对D-半乳糖衰老模型小鼠抗衰老作用的实验研究[J]. 刨伤外科杂志, 2008, 10(3): 257-259.
[11] Anne L Lardner.Neurobiological effects of the green tea constituent theanine and its potential role in the treatment of psychiatric and neurodegenerative disorders[J]. Nutritional Neuroscience, 2014, 17(4): 145-155.
[12] 彭彬, 刘仲华, 林勇, 等. L-茶氨酸改善慢性应激大鼠抑郁行为作用研究[J]. 茶叶科学, 2014, 34(4): 355-363.
[13] 王庆利, 张力军, 吴明春, 等. 茶氨酸对脑缺血损伤大鼠自由基代谢的影响[J]. 实用医学杂志, 2008, 24(11): 1898-1900.
[14] 王玉芬, 秦志祥, 唐振山, 等. 茶氨酸对家兔脑缺血后lL-8和NSE及脑超微结构的影响[J]. 中国医师杂志, 2007, 9(1): 4-6.
[15] 王小雪, 邱隽, 宋宇, 等. 茶氨酸的抗疲劳作用研究[J]. 中国公共卫生, 2002, 18(3): 315-318.
[16] Yokogoshi H, Mochizuki M, Saitoh K.Theanine-induced reduction of brain serotonin concentration in rats[J]. Bioscience Biotechnology Biochemistry, 1998, 62(4): 816-817.
[17] Li G, Ye Y, Kang J, et al.L-Theanine prevents alcoholic liver injury through enhancing the antioxidant capability of hepatocytes[J]. Food Chem Toxicol, 2012, 50(2): 363-372.
[18] 王宝恩, 张定凤. 现代肝脏病学[M]. 北京: 科学出版社, 2003, 67-77.
[19] Sakaguchi S, Furusawa S.Oxidative stress and septic shock: metabolic aspects of oxyfen-derived free radicals generated in the liver during endotoxemia[J]. FEMS Immunol Med Microbiol, 2009, 39(9): 167-177.
[20] 苏磊, 刘志锋. “肠-肝轴”与脓毒症[J]. 中华急诊医学杂志, 2010, 19(2): 124-125.