Mitochondria Meet the Lung Microbiome: A Bidirectional Dialogue in Inflammation and Respiratory Diseases

The respiratory tract is a dynamic biological interface where microbiome, environmental exposure, epithelial integrity, and host metabolic regulation converge to maintain pulmonary homeostasis. Once considered sterile, the lung is now recognized as a low-biomass yet structured microbial ecosystem that contributes to immune calibration, colonization resistance, epithelial barrier function, and tissue resilience. Disruption of this equilibrium, known as pulmonary dysbiosis, has been increasingly associated with acute and chronic lung diseases, including cystic fibrosis, chronic obstructive pulmonary disease, acute respiratory distress syndrome, idiopathic pulmonary fibrosis, asthma, bronchiectasis, and lung cancer. In parallel, mitochondria have emerged as central regulators of pulmonary cell function, extending beyond ATP production to control redox signaling, apoptosis, innate immunity, epithelial repair, and inflammatory responses. This review examines the bidirectional crosstalk between the respiratory microbiome and mitochondria as an integrated pathogenic axis in lung disease. Dysbiotic microbial communities and respiratory pathogens can induce mitochondrial stress through toxins, virulence factors, microbial metabolites, and pattern-recognition receptor activation, leading to mitochondrial alteration and the release of mitochondrial damage-associated molecular patterns. Conversely, dysfunctional mitochondria reshape the pulmonary microenvironment by altering oxygen consumption, nutrient availability, cytokine production, redox balance, and barrier repair, thereby favoring pathogen persistence and chronic inflammation. Understanding mitochondria-microbiome interactions may support precision medicine strategies that integrate microbial, metabolic, inflammatory, and bioenergetic biomarkers to improve the diagnosis, prognosis, and treatment of inflammatory-related lung diseases.