Possible regenerative effect of exosomes released from adipose-derived stem cells on oleic acid-induced acute lung injury in rats

Acute lung injury (ALI) is a respiratory distress that is a major source of morbidity and mortality in the patient population. The pathogenesis of AAH is explained by destruction of both the vascular endothelium and the alveolar epithelium. Adipose-derived stem cells, also known as adipose-derived mesenchymal stem cells (ASC), are mesenchymal stem cells obtained from adipose tissue by minimally invasive methods that contribute to cell/tissue regeneration and have the ability to differentiate into different types of tissues/cells. On the other hand, exosomes are extracellular vesicles secreted by most cells and involved in intercellular communication, and they contain proteins, DNA, mRNA, miRNA, lncRNA, circRNA, etc. carry molecules. Stem cells and exosomes have been used frequently in respiratory diseases. In this study, the therapeutic effects of adipose-derived stem cells and exosomes isolated from these cells were compared in acute lung injury. For this, lung injury was induced with oleic acid (60 mg/kg) administered intravenously (i.v.) to Wistar Albino rats. When examined histopathologically, according to damage scoring, 1x106 adipose-derived stem cells (i.v.) administered 2.5 hours after the injury provided a visible improvement in the parameters of infiltration, hyperplasia, edema and bleeding that occurred after the damage was created with oleic acid, and exosomes (exosomes obtained from 1x106 cells were obtained) i.v. in 500 µl of PBS) did not reverse the damage caused by oleic acid. Total Antioxidant Level (TAS) and Total Oxidant Level (TOS) of the serum analyzed in cardiac blood could not be evaluated due to hemolysis in the samples. In addition, there was no significant difference in the expression levels of IL-6, IL-10 and VEGF genes between the control, oleic acid, adipose stem cell treatment group and exosome treatment group. As a result, when adipose-derived mesenchymal stem cells and exosomes were evaluated histopathologically in order to create a therapeutic effect in oleic acid-induced lung damage in Wistar Albino male rats, it was found that the adipose stem cell treatment group had a curative effect compared to the exosome treatment group, but did not create a significant difference in the level of gene expression.