Dietary Fiber Deficiency Compromises Lung Defense to Resistant Klebsiella and Gut Resistance

This study demonstrates that a low fiber diet disrupts gut microbiota composition, impairing lung defenses against antimicrobial-resistant AMR, Klebsiella pneumoniae KP B31 and promoting antibiotic resistance in the gut. Using a mouse model, researchers found that fiber deprivation increased susceptibility to lung infection, worsened lung inflammation, and amplified ampicillin resistant Enterobacteriaceae in the gut post infection. Fecal microbiota transplantation (FMT) from low fiber fed mice to germfree mice replicated the heightened susceptibility, confirming microbiota dependency. Reduced levels of short-chain fatty acids SCFAs, particularly propionate, were observed in low fiber groups, with in vitro assays showing SCFAs, especially butyrate inhibited KP B31 growth. The findings highlight the gut lung axiss role in immune regulation and suggest dietary fiber as a critical modulator of microbial resistance and host defense. This underscores the potential of dietary interventions to mitigate AMR risks by maintaining gut microbiota health.