对人体有营养物质的健康氨基酸

茶氨酸是铁观音茶叶特有的一种氨基酸，也是茶叶重要的呈味物质之一。

茶氨酸的神经保护作用，特别是在提升认知水平、缓解焦虑、提高睡眠质量、改善抑郁症状等“精神健康”方面，逐渐得到证实。因此，茶氨酸被部分学者称作“幸福氨基酸”。

茶氨酸的神经保护作用

动物实验结果显示，茶氨酸可触发抑郁小鼠的抗抑郁和抗氧化活性效应。

通过双盲、随机对照研究发现，L-茶氨酸能有效影响50 ~ 69 岁参试者的认知功能；通过对30名健康个体的随机对照试验发现，服用L-茶氨酸（200 mg/d）4 周后能够通过抗焦虑作用来改善睡眠质量问题。

相比单独摄入茶氨酸，“茶氨酸复合配方”尤其是茶氨酸和咖啡碱的协同作用，在促进“精神健康”方面更为显著。

在对27 名受试者进行茶氨酸（100 mg） 和咖啡碱（50 mg）联合干预实验发现，受试者的认知水平显著提升。

丨茶氨酸对人脑α波的影响

茶氨酸的延缓衰老作用

在抗衰老模式生物秀丽线虫中，茶氨酸从成虫期干预可以使其平均寿命和最大寿命分别延长约3.6%和3.2%。

在热应激和氧化应激条件下，茶氨酸（100 mg/mL） 显著提高了线虫的平均寿命，2 种条件下分别提高了12.8%和21.3%。茶氨酸可降低空间隔离状态下雄性小鼠大脑皮层氧化损伤水平，提高其存活率。

在强制活动空间环境下，茶氨酸（6 mg/kg）可有效改善速衰小鼠的脑萎缩程度，并维持正常衰老小鼠的脑容积。

因此，安溪铁观音茶氨酸对延缓衰老及预防老年性疾病也具有积极的作用。

茶氨酸的免疫调节作用

据《美国科学院学报》报道，茶氨酸具有提高机体免疫功能和抗感染能力。

火东晓等发现L-茶氨酸抑制细胞因子调节免疫细胞，缓解炎症反应。适宜剂量L-茶氨酸（200 mg/kg）可通过改善肠道发育和健康来调节免疫作用，对肉仔鸡的生长性能产生有益影响。

服用茶氨酸复合制剂可增强人（23.3 mg/kg，口服）和小鼠（120 ~ 700 mg/kg，灌胃） 细胞免疫和体液免疫功能。

在SD雄性大鼠干预实验发现，L-茶氨酸（600 mg/(kg·d)）能够促进肠道绒毛增长，隐窝加深，缓解肠毒素大肠杆菌（E44813）对肠道应激影响。在体外研究发现，茶氨酸可通过提高免疫能力抑制小鼠肝癌细胞增殖。

茶氨酸的代谢调节作用

茶氨酸在动物和人体中还具有显著的抗应激和调节代谢作用。

灌胃干预2周后，L-茶氨酸（50 mg/kg）可以通过下调大鼠小肠中相关基因的表达，抑制葡萄糖、氮的吸收和胰岛素的分泌，改善葡萄糖耐量和胰岛素敏感性，降低乙胺水平和Ⅱ型糖尿病的发病风险。

此外，茶氨酸还能通过增强谷胱甘肽（GSH）及其相关酶抗氧化系统提高对阿霉素（DOX）致大鼠肾毒性的保护作用。

茶氨酸（200 ~ 500 μmol/L）能够有效缓解高剂量EGCG （1 000 μmol/L）对秀丽线虫寿命的健康损害。via：《铁观音茶叶功能成分的健康作用研究新进展》作者：刘仲华等。

Theanine is an amino acid unique to tea and one of the important flavor substances of tea.

The neuroprotective effects of theanine, especially in "mental health" such as improving cognition, relieving anxiety, improving sleep quality, and improving depressive symptoms, have been gradually confirmed. Therefore, theanine is called "happiness amino acid" by some scholars.

Neuroprotective effects of theanine

Animal experiments showed that theanine could trigger antidepressant and antioxidant activity effects in depressed mice.

Through a double-blind, randomized controlled study, it was found that L-theanine can effectively affect the cognitive function of participants aged 50 to 69 years; a randomized controlled trial of 30 healthy individuals found that taking L-theanine (200 mg /d) Can improve sleep quality problems through anxiolytic effects after 4 weeks.

Compared with ingesting theanine alone, the "theanine compound formula", especially the synergistic effect of theanine and caffeine, is more significant in promoting "mental health".

In a combined intervention experiment with theanine (100 mg) and caffeine (50 mg) in 27 subjects, it was found that the cognitive level of the subjects was significantly improved.

丨The effect of theanine on human brain alpha waves

Anti-aging effect of theanine

In the anti-aging model organism C. elegans, theanine intervention from the adult stage can prolong the mean and maximum lifespan by about 3.6% and 3.2%, respectively.

Under heat stress and oxidative stress, theanine (100 mg/mL) significantly increased the mean lifespan of nematodes by 12.8% and 21.3%, respectively. Theanine can reduce the level of oxidative damage in the cerebral cortex of male mice under spatial isolation and improve their survival rate.

In the environment of forced activity space, theanine (6 mg/kg) can effectively improve the degree of brain atrophy in rapidly aging mice, and maintain the brain volume of normal aging mice.

Therefore, theanine also has a positive effect on delaying aging and preventing senile diseases.

Immunomodulatory effects of theanine

According to the "Proceedings of the National Academy of Sciences", theanine has the ability to improve the body's immune function and anti-infection.

Huo Dongxiao et al found that L-theanine inhibits cytokines to regulate immune cells and relieve inflammation. Appropriate doses of L-theanine (200 mg/kg) may have beneficial effects on growth performance in broilers by modulating immune function by improving gut development and health.

Taking the theanine compound preparation can enhance the cellular and humoral immunity of humans (23.3 mg/kg, oral) and mice (120-700 mg/kg, gavage).

In SD male rats intervention experiments, it was found that L-theanine (600 mg/(kg d)) can promote the growth of intestinal villi, deepen the crypts, and alleviate the effect of enterotoxin Escherichia coli (E44813) on intestinal stress. In vitro studies have found that theanine can inhibit the proliferation of liver cancer cells in mice by improving immune ability.

Metabolic regulation of theanine

Theanine also has significant anti-stress and metabolic regulating effects in animals and humans.

After 2 weeks of gavage intervention, L-theanine (50 mg/kg) can inhibit the absorption of glucose and nitrogen and the secretion of insulin by down-regulating the expression of related genes in the small intestine of rats, improve glucose tolerance and insulin sensitivity, and reduce the Ethylamine levels and risk of developing type 2 diabetes.

In addition, theanine can also improve the protective effect of doxorubicin (DOX)-induced nephrotoxicity in rats by enhancing the antioxidant system of glutathione (GSH) and its related enzymes.

Theanine (200 ~ 500 μmol/L) can effectively alleviate the health damage of high-dose EGCG (1 000 μmol/L) on the lifespan of C. elegans. via: "New progress in research on the health effects of functional components of tea" Author: Liu Zhonghua et al.