Influences of PM2.5 on gut physiology, microbiota and metabolites

PM 2.5 (fine particulate matter) has become a significant contributor to global health risks. Emerging evidence links PM 2.5 exposure to chronic diseases via gut-mediated pathways, including systemic inflammation and oxidative stress. These processes disrupt intestinal barrier integrity (e.g., reducing occluding and ZO-1 expression) and increase intestinal permeability, facilitating harmful substance translocation within the organism. Crucially, PM 2.5 exposure significantly alters gut microbiota composition: increasing Lactobacillus , Parabacteroides , Firmicutes and Akkermansia abundance, while decreasing Bacteroidetes and short-chain fatty acid (SCFA)-producing bacteria (e.g., Prevotella ). Concomitant metabolite disturbances feature impaired SCFA synthesis and phosphatidylcholine metabolic dysregulation. These microbiota and metabolite shift collectively impair gut-brain axis function. Therefore, enhanced PM 2.5 pollution control is vital for gut health maintenance and disease prevention. This review summarizes the impact of PM 2.5 on gut structure, microbiota, metabolites and their mechanistic links to systemic health. • ·Exposure to PM 2.5 significantly altered the gut physiology and function. • ·PM 2.5 exposure impact gut microbiota and metabolites. • ·PM 2.5 exposure disrupts the interaction between gut microbiota and metabolites.