Immuno-metabolic reprogramming in pulmonary fibrosis: Emerging therapeutic targets beyond inflammation

Pulmonary fibrosis is a progressive interstitial lung disease characterized by excessive extracellular matrix deposition, tissue remodeling, and irreversible loss of lung function. Although inflammation contributes to disease progression, increasing evidence indicates that immunometabolic reprogramming is a central driver of fibrotic persistence. Alterations in glycolysis, mitochondrial function, lipid metabolism, and redox homeostasis actively regulate immune responses, fibroblast activation, and epithelial cell dysfunction, thereby sustaining a profibrotic microenvironment. This review synthesizes current advances in understanding how metabolic pathways regulate immune and structural cell behavior during pulmonary fibrosis. Particular emphasis is placed on metabolic checkpoints, including mammalian target of rapamycin (mTOR), AMP-activated protein kinase (AMPK), and nicotinamide adenine dinucleotide (NAD⁺)-dependent signaling, which integrate metabolic and inflammatory responses. We further discuss how mitochondrial dysfunction, hypoxia-inducible factor-1α (HIF-1α), reactive oxygen species (ROS), cellular senescence, and metabolic memory contribute to disease persistence. Emerging evidence supports metabolic crosstalk between immune cells and fibroblasts as a key mechanism driving fibrotic remodeling. Finally, we evaluate therapeutic strategies targeting immunometabolic pathways and discuss current translational challenges, including cellular heterogeneity, pathway redundancy, and limited clinical validation. Collectively, this review highlights immunometabolic regulation as a promising therapeutic framework and identifies opportunities for precision-based interventions in pulmonary fibrosis.