Use quercetin for pulmonary fibrosis: a preclinical systematic review and meta-analysis.

Background: Pulmonary fibrosis (PF) is an age-related interstitial lung disease, which lacks effective drug treatment at present. Quercetin has been shown to have favorable anti-inflammatory and anti-fibrotic properties, and preliminary evidence suggests its potential efficacy and tolerability in PF patients. However, a comprehensive systematic review and evaluation of the protective effects and potential mechanisms of quercetin in PF models remains to be completed. Therefore, we conducted this study.

Methods: The PubMed, Cochrane Library, Embase, and Web of Science databases were searched up to the April 1, 2024. CAMARADES was the methodological quality assessment tool. And statistical analyses were conducted with R and Stata 16.0. Origin was used for a three-dimensional (3D) dosage-intervention duration-efficacy model for quercetin treatment of PF.

Results: A total of 20 studies, encompassing 44 independent experiments and involving 1019 animals, were included in the analysis. Meta-analysis revealed that quercetin significantly mitigated lung pathological tissue scores and the expression of lung fibrosis markers in PF animal models. Furthermore, quercetin significantly ameliorated inflammatory responses, oxidative stress, epithelial-mesenchymal transition and myofibroblast activation, cell senescence and apoptosis, and the markers expression of extracellular matrix (ECM) deposition. Quercetin did not show significant hepatic and nephrotoxicity. The 3D dosage-intervention duration-efficacy model indicated that a dosing period over 20 days and dosages range of 5-100 mg/kg were appropriate modalities.

Conclusion: Herein, our study highlights the potential of quercetin in the treatment of PF and the available mechanisms.