Eugenol mitigates pulmonary fibrosis in mice by modulating gut–lung microbiota and reducing inflammation

The increasing incidence of pulmonary fibrosis (PF) poses a serious threat to patient survival, and effective treatments are lacking. Eugenol, known for its anti-fibrotic properties, has not been extensively studied for PF treatment. The aim of this study was to explore potential drugs for the treatment of pulmonary fibrosis and the use of plant-derived compounds with proven anti-hepatic fibrosis effects. We evaluated the therapeutic effect of eugenol in a bleomycin-induced mouse model of PF and examined its mechanisms, focusing on pathological changes and gut-lung microbiota. Oral eugenol significantly reduced mortality and decreased inflammatory markers, α-SMA, and collagen I and fibronectin, while restoring the diversity and homeostasis of the gut and lung microbiota in mice. The potential anti-fibrotic effects of oral eugenol may involve multiple mechanisms, including its anti-inflammatory property and its close association with the restoration of gut-lung microbial homeostasis, suggesting its promise as a clinical treatment.