MicroRNA-21 Attenuates Hepatocyte Hypoxia/Reoxygenation Injury Via PTEN/PI3K/Akt Signaling Pathway

Objective: To observe the regulatory role and the mechanism involved of MicroRNA-21 in mouse primary hepatocytes during hypoxia/reoxygenation injury(H/R).Methods:Primary mouse hepatocytes were isolated and divide into four groups:a control group,a H/R group(H/R),a vehicle group(transfected Lipofectamine 2000 then subjected to H/R),a miR-21+H/R group(transfected agomir-21 then subjected to H/R),The expression of miR-21 was detected with Real-time PCR,Flow cytometry(FCM)was used to examine apoptosis of the groups.The expression of PTEN/PI3K/Akt signaling pathway related proteins were detected by Western blot.In order to find out the regulatory effects of miR-21 on PTEN,PI3 K inhibitor was given after transfected agomir-21 and then subjected to H/R.FCM was used to examine apoptosis of the groups.The expression of PTEN/PI3K/Akt signaling pathway related proteins detected by Western blot.Results:Compared with control group,the expression of miR-21 increased in H/R group,vehicle group and miR-21+H/R group.The apoptotic rate of the miR-21+H/R group was lower than the H/R group or the vehic le group and overexpression of miR-21 produced a inhibitive effect on the expression of PTEN,then increased Akt phosphorylation.The Bcl-2/Bax and the expression of Bcl-2 was increased and caspase-3 was downregulated in the miR-21+H/R group than the H/R group or the vehicle group.But if the cells were treated by PI3 K inhibitor after transfected agomir-21,The apoptotic rate of it was higher than the miR-21+H/R group.The expression of P-Akt and Bcl-2 and the Bc l-2/Bax was decreased than the miR-21+H/R group.And caspase-3 of the duplex treatment group was upregulated.Conclusion: MiR-21 can alleviate cell apoptosis induced by H/R.miR-21 may protect hepatocyte from the hypoxia/ reoxygenation injury via inhibit the expression of PTEN.