LncRNA KCNQ10T1 shuttled by bone marrow mesenchymal stem cell-derived exosome inhibits sepsis via regulation of miR-154-3p/RNF19A axis.

This study aims to discuss the role of exosomes KCNQ10T1 derived from bone marrow mesenchymal stem cells (BMMSCs) in sepsis and to further investigate its potential molecular mechanisms. Exosomes extracted from BMMSCs are identified by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blot. Fluorescence labeling is applied to detect the internalization of exosomes in receptors. The proliferation ability, migration ability, and invasion ability of HUVECs are determined by CCK-8, EdU, wound healing, and Transwell. The levels of inflammatory cytokines in sepsis cells are quantitatively detected by ELISA. Kaplan-Meier survival curve is used to describe the overall survival. RT-qPCR is used to detect mRNA expression of related genes. Bioinformatics analysis is performed to search the downstream target of KCNQ1OT1 and miR-154-3p and the interaction is verified by luciferase reporter assay. Exosomes derived from BMMSCs alleviated the toxicity in sepsis cell models and animal models. In mice with septic cell models, exosomal KCNQ10T1 was down-regulated and associated with lower survival. Overexpression of KCNQ10T1 inhibited the proliferation and metastasis of LPS-induced HUVECs. Further research illustrated that miR-154-3p was the downstream target gene of KCNQ1OT1 and RNF19A was the downstream target gene of miR-154-3p. Importantly, functional research findings indicated that KCNQ1OT1 regulated sepsis progression by targeting miR-154-3p/RNF19A axis. Our study demonstrates that the exosomal KCNQ1OT1 suppresses sepsis via mediating miR-154-3p/RNF19A, which provides a latent target for sepsis treatment.