Anti-inflammatory Effect Of MicroRNA-19b-3p In Human Adipose-derived Stem Cell Exosome And Its Application In Animal Model Of Acute Liver Failure

Objective: Previously,high throughput sequencing showed that exosomes derived from human adipose stem cells(hASCs)could inhibit inflammation and chemotaxis-related signaling pathways in liver tissues of rats with acute liver failure(ALF)This study aims to explore the possible mechanism of the anti-inflammatory effect of microRNAs(miRNAs)with anti-inflammatory effects overexpressed in exosomes.Methods: 1.The effects of miRNAs with anti-inflammatory effects overexpressed in exosomes on the release of reactive oxygen species(ROS),inflammatory factors(IL-1a,IL-6 and TNF-a)and apoptotic rate of macrophages activated by D-galactosamine hydrochloride(D-gal)and lipopolysaccharide(LPS)were detected by confocal microscopy,ELISA and flow cytometry,and the miRNAs with the strongest anti-inflammatory effect were screened.2.ALF rats induced by D-gal/LPS were treated with exosomes or over-expressed of the strongest anti-inflammatory miRNA exosomes,respectively.or Lentiviral preconditioning with over-expression of the strongest anti-inflammatory effect of miRNA in rats and D-gal/LPS was used to induce ALF.The survival rate,liver function and the changes of “P47phox-ROS-inflammatory factors(IL-10,IL-1a,IL-6,TNF-?)” pathway in liver tissue were observed.Result: Among the six anti-inflammatory miRNAs highly expressed in exosomes,the anti-inflammatory effect of miRNA-19b-3p on activated macrophages was the strongest.The expression of P47 phox,ROS,IL-1a,IL-6 and TNF-? in activated macrophages was significantly inhibited by free or exosome form of miRNA-19b-3p,and the expression of IL-10,an inflammatory inhibitory cytokine,was also promoted.Over-expression of miRNA-19b-3p exosome therapy or over-expression of miRNA-19b-3p lentivirus pretreatment significantly improved the general condition,24-hour survival rate and pathological changes of liver tissues in rats with ALF,and restricted the expression of P47 phox,ROS and a variety of inflammatory and chemokines in liver tissues.Conclusion: The exosomes overexpressing miRNA-19b-3p can inhibit the expression of inflammatory factors and chemokines by inhibiting the P47phox-ROS pathway in activated macrophages or liver tissues of ALF rats,thus improving the survival rate of ALF rats.