The injury of serotonin on intestinal epithelium cell renewal of weaned diarrhoea mice

Abstract

Diarrhoea is a common cause of death in children and weaned animals. Recent research has found that serotonin (5-HT) in the gastrointestinal tract plays an important role in regulating growth and the maintenance of mucosa, which protect against diarrhoea. To determine the influence of 5-HT on intestinal epithelium cell renewal under weaned stress diarrhoea, a weaned-stress diarrhoea mouse model was established with senna infusion (15 mL/Kg) via intragastric administration and stress restraint (SR). Mice with an increase in 5-HT were induced by intraperitoneal injection with citalopram hydrobromide (CH, 10 mg/Kg). The results demonstrated that compared with the control animals, diarrhoea appeared in weaned stress mice and the 5-HT content in the small intestine was significantly increased (P<0.05). Further, the caspase-3 cells and cells undergoing apoptosis in the small intestine were significantly increased, but the VH (villus height), V/C (villus height /crypt depth), and PCNA-positive rate significantly decreased. Compared with the control animals, CH increased the intestinal 5-HT content, caspase-3 cells and cells undergoing apoptosis but decreased the VH and V/C. Compared with both control and weaned stress animals, weaned stress animals that were pre-treated with CH showed higher 5-HT concentrations, positive caspase-3 cells and cells undergoing apoptosis but lower VH, V/C and PCNA-positive rate. In vitro, a low concentration of 5-HT inhibit, IEC-6 cell line apoptosis but a higher concentration of 5-HT promoted it. Therefore, weaned stress diarrhoea mice were accompanied by a 5-HT increase in the small intestine and vice versa, and the increase in 5-HT induced by CH caused diarrhoea. In brief, 5-HT and diarrhoea slowed the intestinal epithelium cell renewal and injured the abortion function and mucosal barrier by decreasing VH, V/C and proliferation and increasing epithelium cell apoptosis.

Supplementation of Diet With Different n-3/n-6 PUFA Ratios Ameliorates Autistic Behavior, Reduces Serotonin, and Improves Intestinal Barrier Impairments in a Valproic Acid Rat Model of Autism

“…found that the intestinal and plasma 5-HT levels were higher in the stressed animals, and the elevated 5-HT level could lead to diarrhea. 5-HT and diarrhea delayed the renewal of intestinal epithelial cells and impaired the mucosal barrier and absorption ( 25 ). In autism population and their relatives, the blood 5-HT level increases, implicating the involvement of 5-HT in the pathophysiology of autism ( 26 ).…”

Long-term effect of parasympathetic or sympathetic denervation on intestinal epithelial cell proliferation and apoptosis

“…Since serotonin receptors have also been found to be involved in intestinal epithelial proliferation, upregulation of the receptors after PNS denervation may contribute to the recovery of cell turnover. 43,44 Changes in the specific primary neurotransmitter receptors of the denervated ANS branch are also likely to undergo changes to facilitate recovery of the intestinal epithelial turnover. PNS denervation upregulates the amount of muscarinic acetycholinergic gene expression in the stomach 45 and downregulates the expression in the small intestine 46 The intact branch of the ANS may also participate in the compensation to recover function after denervation.…”

Gardenia Decoction Prevent Intestinal Mucosal Injury by Inhibiting Pro-inflammatory Cytokines and NF-κB Signaling

“…VH and CD of intestinal mucosa are closely related to animal digestion. Detection of VH and CD can judge the degree of intestinal mucosal damage and the ability to repair (Dong et al, 2016). Thus, an increase in VH, V/C or decrease in the CD corresponds to an improvement in the digestion and absorption of nutrients (Hou et al, 2013).…”