Ting Zheng, Yi Huang, Hongmei Yao
BACKGROUND: Bronchial asthma (hereafter referred to as asthma) is a heterogeneous disease characterized by chronic airway inflammation, airway hyperresponsiveness (AHR), and reversible airflow limitation. Recent advancements in the "gut-lung" axis concept have elucidated the intricate immunometabolic crosstalk between the gastrointestinal tract and pulmonary system, offering novel insights into the pathogenesis and therapeutic strategies for asthma. OBJECTIVE: Exploring the research progress of the "gut-lung" axis in bronchial asthma, providing new insights into the pathogenesis and treatment of asthma. METHODS: This article reviewed a large number of relevant studies, elucidating the role of the "gut-lung" axis in bronchial asthma, and further discussing the potential of the microbiota in the treatment of bronchial asthma. CONCLUSION: Gut microbiota and their metabolites exert profound effects on pulmonary immune homeostasis through immune modulation, metabolic signaling, and neuroendocrine pathways, which are critically implicated in asthma pathogenesis. Conversely, systemic immune dysregulation in asthma may reciprocally induce intestinal barrier dysfunction. Asthma is a variable disease here. It may be that some of this variability relates to different diets or environmental/gut exposures although this needs to be confirmed in human studies. This review comprehensively delineates the mechanistic role of the gut-lung axis in asthma, encompassing microbiota-immune system interactions, regulatory effects of microbial-derived metabolites such as short-chain fatty acids (SCFAs) and bile acids, and microbiota-targeted therapeutic approaches including probiotics, dietary interventions, and metabolite-based therapies. Furthermore, we also discuss the limitations and future development directions of current research to provide new ideas for precision treatment of asthma.