Journal of Functional Foods (Jan 2020)

Effects of l-theanine on glutamine metabolism in enterotoxigenic Escherichia coli (E44813)-stressed and non-stressed rats

  • An Liu,
  • Zhihua Gong,
  • Ling Lin,
  • Wei Xu,
  • Tuo Zhang,
  • Sheng Zhang,
  • Yinhua Li,
  • Jinhua Chen,
  • Wenjun Xiao

Journal volume & issue
Vol. 64
p. 103670

Abstract

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l-theanine, a non-protein-derived amino acid, is widely used as a functional ingredient in foods. Here, we evaluated the in vivo effects of l-theanine on glutamine metabolism in healthy rats and in a stressed rat model, which was established by infecting rats with enterotoxigenic Escherichia coli (E44813). The results showed that l-theanine significantly enhanced the synthesis of glutamine and stabilized the intestinal tract in healthy rats. In E44813-stressed rats, l-theanine could replace l-glutamine, thereby alleviating intestinal stress by reducing the expression of inflammatory factors, enhancing the activities of antioxidant enzymes, and regulating glutamine metabolism by modulating its synthesis. Treatment with a combination of l-theanine and l-glutamine was superior to treatment with l-glutamine alone in enhancing the activity of antioxidant enzymes, reducing the expression of inflammatory factors, and increasing the intestinal villi height and crypt depth.

Keywords