Oat Fiber Alleviates Loperamide-Induced Constipation in Mice by Modulating Intestinal Barrier Function.

Area of Science:

• Gastroenterology
• Microbiology
• Nutrition Science

Background:

• Constipation is a common gastrointestinal disorder with significant impact on quality of life.
• Dietary fiber, particularly oat fiber, is recognized for its potential role in managing digestive health.
• Understanding the mechanisms by which oat fiber affects gut function is crucial for therapeutic development.

Purpose of the Study:

• To investigate the efficacy of oat fiber in alleviating loperamide-induced constipation in a mouse model.
• To elucidate the underlying mechanisms of oat fiber's action on gastrointestinal physiology and microbiota.

Main Methods:

• Male BALB/c mice were induced with constipation using loperamide.
• Oat fiber was administered intragastrically at low, middle, and high doses for 21 days.
• Key parameters assessed included fecal output, intestinal transit, gastrointestinal peptide levels, gut microbiota composition, and inflammatory markers.

Main Results:

• Oat fiber significantly increased fecal output and water content, and improved intestinal transit time.
• It modulated gastrointestinal peptides, including upregulation of motilin (MTL) and gastrin (GAS), and downregulation of vasoactive intestinal peptide (VIP) and somatostatin (SS).
• Oat fiber reduced inflammatory markers (TNF-α, IL-1β), decreased Aquaporin 8 (AQP8) expression, and enhanced gut microbiota diversity, favoring Firmicutes over Bacteroidetes.

Conclusions:

• Oat fiber demonstrates significant efficacy in ameliorating constipation in mice.
• Its therapeutic effects are mediated through modulation of gastrointestinal regulatory peptides, enhancement of gut microbiota, and reduction of intestinal inflammation and barrier damage.