Gut microbiota impact on lung diseases: a mini review of clinical evidence

The gut-lung axis represents a bidirectional communication network through which the gut microbiota (GM) influences respiratory health. This mini-review synthesizes clinical evidence on the role of the GM in lung diseases. We focused exclusively on human clinical trials, randomized controlled trials, meta-analyses, and systematic reviews, sourced from major databases after duplicate removal. The evidence indicates that GM dysbiosis is a significant risk factor for the susceptibility and severity of various respiratory conditions, including asthma, chronic obstructive pulmonary disease (COPD), cystic fibrosis (CF), and infections, such as COVID-19 and pneumonia. Specific microbial signatures and metabolic profiles, particularly involving short-chain fatty acids (SCFAs), are associated with disease states and outcomes. Interventions like probiotics, prebiotics, synbiotics, and fecal microbiota transplantation (FMT) show promise in modulating the GM and improving clinical parameters, though their efficacy can be inconsistent and influenced by confounding factors. In conclusion, the GM is a promising therapeutic target for lung diseases. However, future research must prioritize large-scale, longitudinal clinical trials and deeper mechanistic investigations to establish causality and develop effective, personalized microbiome-based therapies.