Role of AMPK-mediated mitochondrial fusion and fission in inhibiting P2X7 receptor anti-hypoxia/reoxygenation injury of neurons

ObjectiveTo investigate the role of mitochondrial fusion and fission regulated by AMPK in the protective effects of inhibiting P2X7 receptor against hypoxia/reoxygenation injury in neurons.

MethodsThe primary neurons were cultured, and randomly divided into the Control group, hypoxia/reoxygenation(H/R) group, H/R+Bright Blue G(BBG) group, H/R+BBG+Dorsomorphin group.The viability of neurons was assessed using Calcein-AM/PI kit, the ROS level was detected using ROS kit, the morphology of mitochondrial morphology was detected using Mito Tracker TM Green FM kit, and the expression levels of p-AMPK, p-Drp1 and Mfn2 were detected using Western blotting.

ResultsCompared with Control group, the death rate, mitochondrial fission and level of ROS in neurons increased significantly in H/R group.After pretreated with BBG, the death rate, fission of mitochondrial and level of ROS in neurons with H/R injury decreased significantly, while the protective effects of inhibitor of AMPK Dorsomorphin on neurons with H/R injury were attenuated(P < 0.01).Compared with the Control group, the results of Western blotting showed that the expression levles of p-AMPK and Mfn2 decreased significantly, while the expression level of p-Drp1 increased markedly in H/R group(P < 0.01).After pretreated with BBG, the expression levels of p-AMPK and Mfn2 increased significantly, while the expression level of p-Drp1 decreased markedly.The inhibitor of AMPK Dorsomorphin weakened the BBG increasing the expression levels of p-PMAK and Mfn2 in H/R injured neurons and decreas the expression level of p-Drpl(P < 0.01).

ConclusionsThe inhibition of P2X7 receptor can reduce the damage of neurons induced by H/R injury through inhibiting mitochondrial fission to promote mitochondrial fusion, which may be involved in the activation of AMPK.