Mechanism underlying rat hepatocyte apoptosis regulated by exosomes derived from bone marrow mesenchymal stem cells

Zheng Rongjiong; Deng Zerun; Han Dan; Sun Lihua

doi:10.12307/2023.916

Abstract：BACKGROUND:Bone marrow mesenchymal stem cells(BMSCs)can release a large number of exosomes(Exos).The effect of Exos derived from BMSCs on hepatocyte apoptosis and the specific mechanism has not been fully clarified. OBJECTIVE:To explore the effect of miR-21-5p carried by Exos derived from BMSCs on apoptosis of rat liver cells and its mechanism. METHODS:Rat BMSCs were isolated and miR-21-5p NC or miR-21-5p inhibitor was transfected into BMSCs.The Exos were extracted by ultracentrifugation and named(BMSCs+miR-21-5p NC)-Exos and(BMSCs+miR-21-5p inhibitor)-Exos.BMSCs-derived Exos were co-cultured with rat hepatocytes to observe the effect of inhibiting miR-21-5p expression on the apoptosis of rat hepatocytes.The targeting relationship between miR-21-5p and PIK3R1 was verified by double luciferase reporter gene detection.TUNEL was used to detect the effect of miR-21-5p directly targeting PIK3R1 in Exos to activate the PI3K/AKT signaling pathway on hepatocyte apoptosis in BRL rats. RESULTS AND CONCLUSION:(1)The double luciferase reporting system confirmed that when PI3KR1 wild type vector and miR-21-5p mimics co-transfected 293T cells,the luciferase activity decreased significantly compared with the PI3KR1 mutant vector co-transfected group,indicating that miR-21-5p could target PIK3R1.(2)TUNEL test results showed that compared with(BMSCs+miR-21-5p NC)-Exos group,(BMSCs+miR-21-5p inhibitor)-Exos treatment significantly increased the apoptosis rate.Compared with the(BMSCs+miR-21-5p NC)-Exos group,after the addition of AKT inhibitor LY294002,the apoptosis rate was significantly increased.(3)The results indicate that Exos may inhibit the apoptosis of BRL rat hepatocytes through miR-21-5p,in which miR-21-5p directly targets PIK3R1 to activate PI3K/AKT signaling pathway.