Intestinal Mucosal Barrier and Gut Microbiota

The intestinal flora and intestinal barrier represent a complex, integrated biological system essential for maintaining systemic homeostasis and protecting the host from luminal pathogens and toxins. The intestinal flora, or gut microbiota, consists of trillions of microorganisms that contribute to metabolic processes, vitamin synthesis, and the maturation of the host immune system (Frontiers in Cellular and Infection Microbiology, 2022). The intestinal barrier is a multi-layered structure comprising a chemical barrier (mucus and antimicrobial peptides), a physical barrier (epithelial cells and tight junctions), and an immunological barrier (gut-associated lymphoid tissue) (Nature Reviews Gastroenterology & Hepatology, 2017). Disruption of this system, often referred to as increased intestinal permeability or "leaky gut," is a key pathogenic factor in various systemic and localized inflammatory conditions, including inflammatory bowel disease (IBD), metabolic syndrome, and nonalcoholic fatty liver disease (NIH/PubMed). Therapeutic strategies targeting this system aim to restore microbial balance through probiotics or fecal transplants and strengthen barrier integrity via trophic factors like GLP-2 analogs or specific enzyme inhibitors (Journal of Gastroenterology and Hepatology, 2007).

Other names

Intestinal floraGut microbiomeIntestinal barrierIntestinal mucosal barrierLeaky gutIntestinal permeabilityGut-liver axis

Modulation of microbial composition and diversity, enhancement of tight junction protein expression (e.g., ZO-1, occludin), stimulation of mucus production by goblet cells, and regulation of mucosal immune responses such as secretory IgA production.