Exosome-mediated immunomodulatory and barrier-protective responses of adipose-derived mesenchymal stem cells in oleic acid-induced acute lung injury

Abstract

ABSTRACT Purpose: Acute lung injury (ALI) is a severe pulmonary disorder with limited treatment options. Mesenchymal stem cell-based therapies show regenerative and immunomodulatory potential, but the comparative efficacy of adipose-derived mesenchymal stem cells (ADMSCs) and their exosomes remains unclear. This study evaluated their therapeutic effects in an experimental ALI model. Methods: ADMSCs were isolated from rat adipose tissue and cultured under standard conditions. Exosomes were characterized by flow cytometry (CD9, CD63, CD81), scanning electron microscopy, dynamic light scattering, and zeta potential analysis. ALI was induced in Wistar Albino rats by intravenous administration of 60 mg/kg oleic acid. Treatments were administered 2.5 hours after injury. Lung tissues were examined histopathologically after 24 hours, and mRNA expression levels of interleukin (IL)-6, IL-10, and vascular endothelial growth factor (VEGF) were analyzed. Results: Both ADMSC and exosome treatments significantly reduced lung injury scores compared with the oleic acid group. ADMSCs demonstrated greater histopathological improvement than exosomes, although no significant differences were observed in IL-6, IL-10, or VEGF expression. Conclusion: Both ADMSCs and their exosomes showed therapeutic potential in ALI, with stem cells providing superior histopathological recovery.