Efficacy of High Specific Volume Polysaccharide – A New Type of Dietary Fiber – On Molecular Mechanism of Intestinal Water Metabolism in Rats With Constipation

Abstract

Background The aim of this study was to evaluate the effects of a new type of dietary fiber – high specific volume polysaccharide (HSVP) – on fecal properties, serum vasoactive intestinal peptide (VIP) concentration, intestinal flora count, and expression of the VIP-cAMP-PKA-AQP3 signaling pathway. Marerial/Methods Compound diphenoxylate was used in 48 healthy Wistar rats to establish a constipation model. Rats were divided into a normal control group, a constipation model group, an HSVP low-dose group, an HSVP medium-dose group, an HSVP high-dose group, and a fructose control group. We used colony count method, ELISA, WB, and RT-PCR to determine fecal moisture content, fecal hardness, fecal passage time, serum VIP concentration, number of intestinal bacteria, and VIP-cAMP-PKA-AQP3 signal pathway protein expression. Results The constipation model was established successfully. HSVP (the medium dose was 10% and the high dose was 15%) improved fecal moisture content, reduced hardness, shortened fecal emptying time, increased intestinal bacteria, reduced serum VIP concentration, downregulated cAMP and PKAm RNA transcription, reduced protein expression, and reduced intestinal AQP3 expression. Conclusions HSVP improved constipation, increased the number of intestinal bacteria, and elevated expression of the VIP-cAMP-PKA-AQP3 signaling pathway. The mechanism of HSVP in regulating intestinal water metabolism in constipated rats may occur through the VIP-cAMP-PKA-AQP3 signaling pathway, and be closely related to changes in intestinal bacteria. The important role of the brain-gut-microbiome axis in the pathogenesis of constipation has been confirmed in this study.

Inhibitory Effect of Lactococcus lactis subsp. lactis HFY14 on Diphenoxylate-Induced Constipation in Mice by Regulating the VIP-cAMP-PKA-AQP3 Signaling Pathway

“…Regulating VIP-cAMP-PKA-AQP3 signaling pathway by active substances can inhibit constipation. 44 , 45 At the same time, the study also confirmed that Lactobacillus belongs to a probiotic bacteria, which can be used to regulate the function of the intestine, improve the internal environment of the intestine, regulate the balance of the intestinal microecology, promote the intestinal peristalsis function, and relieve constipation. 46 , 47 None of these studies have yet correlated the effects of probiotics on intestinal water metabolism.…”

Physicochemical properties and bioactivity of polysaccharides from Isaria cicadae Miquel with different extraction processes: effects on gut microbiota and immune response in mice

“…38 In addition, polysaccharide intervention could significantly increase the moisture content of cecal contents and decrease the hardness of intestinal contents, thereby shortening the emptying time of feces to relieve constipation. 39…”

“…Food & Function nal contents, thereby shortening the emptying time of feces to relieve constipation. 39…”

Lactobacillus plantarumKFY02 enhances the relieving effect of gardenoside on montmorillonite induced constipation in mice

“…34 VIP stimulates intestinal peristalsis and promotes gastrointestinal motility. 35 ET maintains normal intestinal function by maintaining vascular tone and cardiovascular stability. 36 SS inhibits the release of gastrointestinal hormones and reduces the gastric emptying speed and smooth muscle contraction, thereby accelerating constipation.…”