Li Chengjian, Tong Haiou, Yan Qiongxian, Tang Shaoxun, Han Xuefeng, Xiao Wenjun, Tan Zhiliang
National Research Center of Engineering Technology for Utilization of Botanical Functional Ingredients from Botanicals, Provincial Co-Innovation Center for Utilization of Botanical Function Ingredients, Hunan Agricultural University, Changsha, Hunan, China (mainland).
Key Laboratory of Agro-ecological Processes in Subtropical Region, Hunan Research Center of Livestock & Poultry Sciences, South-Central Experimental Station of Animal Nutrition and Feed Science in Ministry of Agriculture, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, Hunan, China (mainland).
Med Sci Monit. 2016 Feb 28;22:662-9. doi: 10.12659/msm.897077.
BACKGROUND This study aimed to investigate the regulatory effects of L-theanine on secretion of immune cytokines, hormones, and neurotransmitters, and mRNA expression of phospholipase C (PLC) in rats, and to explore its regulatory mechanism in immune function. MATERIAL AND METHODS Sixty-four Sprague-Dawley rats received daily intragastric infusion of different doses of L-theanine solution [0, 50 (LT), 200 (MT), and 400 (HT) mg/kg BW]. Cytokines, immunoglobulins, and hormones in the serum, neurotransmitters, and mRNA expression of PLC in the relevant tissues were assayed. RESULTS L-theanine administration increased the splenic organ index and decreased the contents of ILs-4/6/10 and the ratio of IL-4/IFN-γ in the serum. High-dose L-theanine administration increased the levels of dopamine and 5-hydroxytryptamine in the pituitary and hippocampus, resulting in decrease in corticosterone level in the serum. L-theanine administration decreased the mRNA expressions of PLC isomers in the liver and PLC-γ1 and PLC-δ1 in the spleen. Interestingly, mRNA expressions of PLC-β1 in the spleen and PLC isomers mRNA in the heart were up-regulated by L-theanine administration. CONCLUSIONS Administration of 400 mg/kg BWL-theanine improved immune function of the rats by increasing the splenic weight, altering the Th2/Th1 cytokine balance, decreasing the corticosterone level in the serum, elevating dopamine and 5-hydroxytryptamine in the brain, and regulating the mRNA expression of PLC isomers in the heart.
背景 本研究旨在探讨L-茶氨酸对大鼠免疫细胞因子、激素和神经递质分泌以及磷脂酶C（PLC）mRNA表达的调节作用，并探讨其在免疫功能中的调节机制。
材料与方法 将64只Sprague-Dawley大鼠每日灌胃不同剂量的L-茶氨酸溶液[0、50（低剂量组，LT）、200（中剂量组，MT）和400（高剂量组，HT）mg/kg体重]。检测血清中的细胞因子、免疫球蛋白、激素、神经递质以及相关组织中PLC的mRNA表达。
结果 给予L-茶氨酸可增加脾脏器官指数，降低血清中白细胞介素-4/6/10的含量以及白细胞介素-4/干扰素-γ的比值。高剂量L-茶氨酸给药可增加垂体和海马中多巴胺和5-羟色胺的水平，导致血清中皮质酮水平降低。给予L-茶氨酸可降低肝脏中PLC异构体以及脾脏中PLC-γ1和PLC-δ1的mRNA表达。有趣的是，给予L-茶氨酸可上调脾脏中PLC-β1以及心脏中PLC异构体mRNA的表达。
结论 给予400mg/kg体重的L-茶氨酸可通过增加脾脏重量、改变Th2/Th1细胞因子平衡、降低血清中皮质酮水平、提高脑中多巴胺和5-羟色胺水平以及调节心脏中PLC异构体的mRNA表达来改善大鼠的免疫功能。
