Ethanol Extract of Mao Jian Green Tea Attenuates Gastrointestinal Symptoms in a Rat Model of Irritable Bowel Syndrome with Constipation via the 5-hydroxytryptamine Signaling Pathway

• Published in: Foods 2023-03, Vol.12 (5), p.1101
• Main Authors: Wu, Lei, Gao, Liming, Jin, Xiang, Chen, Zhikang, Qiao, Xutong, Cui, Xiting, Gao, Jianhua, Zhang, Liwei
• Format: Article
• Language: English
• Subjects: 5-hydroxytryptamine; Bacteria; Caffeine; Calcium-binding protein; Calmodulin; Care and treatment; Chinese medicine; Constipation; Contraindications; Disease; Distension; Drug dosages; Emptying; Enzymes; Ethanol; ethanol extract; FDA approval; Flavonoids; Food science; Gastric emptying; Gastric motility; gastrointestinal motility; Gastrointestinal symptoms; Gastrointestinal system; Gastrointestinal tract; Green tea; gut microbiota; Health aspects; Intestinal microflora; Intestine; Irritable bowel syndrome; Kinases; Mao Jian Green Tea; Materia medica, Vegetable; Metabolites; Microbiota; Moisture content; Motility; Myosin; Myosin-light-chain kinase; Patients; Permeability; Plant extracts; Polyphenols; Serotonin; Serotonin S4 receptors; Serotonin transporter; Signal transduction; Small intestine; Tea; Tryptophan; Tryptophan hydroxylase; Water content
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods12051101

In a previous study, we demonstrated that the hydro extract of Mao Jian Green Tea (MJGT) promotes gastrointestinal motility. In this study, the effect of MJGT ethanol extract (MJGT_EE) in treating irritable bowel syndrome with constipation (IBS-C) in a rat model constructed via maternal separation combined with an ice water stimulation was investigated. First, a successful model construction was confirmed through the determination of the fecal water content (FWC) and the smallest colorectal distension (CRD) volume. Then, the overall regulatory effects of MJGT_EE on the gastrointestinal tract were preliminarily evaluated through gastric emptying and small intestinal propulsion tests. Our findings indicated that MJGT_EE significantly increased FWC ( < 0.01) and the smallest CRD volume ( < 0.05) and promoted gastric emptying and small intestinal propulsion ( < 0.01). Furthermore, mechanistically, MJGT_EE reduced intestinal sensitivity by regulating the expression of proteins related to the serotonin (5-hydroxytryptamine; 5-HT) pathway. More specifically, it decreased tryptophan hydroxylase (TPH) expression ( < 0.05) and increased serotonin transporter (SERT) expression ( < 0.05), thereby decreasing 5-HT secretion ( < 0.01), activating the calmodulin (CaM)/myosin light chain kinase (MLCK) pathway, and increasing 5-HT receptor (5-HT R) expression ( < 0.05). Moreover, MJGT_EE enhanced the diversity of gut microbiota, increased the proportion of beneficial bacteria, and regulated the number of 5-HT-related bacteria. Flavonoids may play the role of being active ingredients in MJGT_EE. These findings suggest that MJGT_EE could serve as a potential therapeutic pathway for IBS-C.