The Neuroprotective Effect Of Aerobic Exercise On Ischemic Brain Injury And Its Mechanism Through The SET Domain Protein 3 Signaling Pathway

Objective: 1.To explore the role and mechanism of SETD3 in ischemic brain injury2.To explore the role of SETD3 in aerobic exercise after strokeMethods: Middle cerebral artery occlusion/reperfusion(MCAO/R)model were used in the research;SETD3 c DNA lentivirus or sh RNA lentivirus were injected into rat brain by stereotactic injection to overexpress or knock down SETD3;Neurological severity scores(NSS)were used to evaluate the neurological function of rats;The rats were trained with electric treadmill.These four methods are implemented at animal level.The infarct size was analyzed by the 2,3,5-triphenyltetrazoliumchloride(TTC)staining;Immunofluorescence were used to detect the expression of SETD3.These two methods are implemented at the organ level.Cell activity detection and lactate dehydrogenase(LDH)release test were used to detect neuronal survival;The expression of SETD3 protein in neurons was overexpressed or knocked down by lentivirus transfection;Mitochondrial function was evaluated by Adenosine triphosphate(ATP)release test,mitochondrial membrane potential and reactive oxygen species(ROS)detection.This part of the experiment was carried out at the cellular level.The methods of western blot(WB)were used to detect the expression of SETD3,PTEN,P-Akt,β-actin.The experiment was carried out at the molecular level.Results: In the first part of this project,we studied whether SETD3 plays a protective role in cerebral ischemia-reperfusion injury and its mechanism.SETD3 participates in the process of ischemia/reperfusion-induced injury.The expression of SETD3 was significantly decreased after ischemia-reperfusion injury of animal models and OGD/reoxygenation(OGD/R),a in vitro model of neuronal ischemia-reperfusion;Overexpression of SETD3 plays a protective role in vitro and vivo model of ischemia-reperfusion injury;SETD3 plays a neuroprotective effect by regulating mitochondrial function in vivo model of neuronal reperfusion injury;SETD3 plays a role in mitochondrial function by regulating actin polymerization in vivo model of neuronal reperfusion injury;SETD3 mediates actin polymerization to play a neuroprotective role in vivo and vitro reperfusion injury models under the regulation of PTEN.In the second part of this project,we studied whether aerobic exercise exerts neuroprotective effect through SETD3 molecular pathway.Aerobic exercise has a neuroprotective effect and up-regulates the expression of SETD3 after cerebral ischemia-reperfusion injury;Down-regulation of SETD3 attenuates the neuroprotective effect of aerobic exercise on rats after ischemic brain injury.Conclusion:This research discovered that SETD3 promoted neuronal survival by preserving mitochondrial function through regulating actin polymerization.In addition,we found that the expression of SETD3 is regulated by PTEN.Aerobic exercise promotes neuroprotection against cerebral ischemia–reperfusion injury via the upregulation of SETD3.Therefore,SETD3 signaling pathway is one of the important molecular mechanisms of aerobic exercise in alleviating cerebral ischemia-reperfusion injury.These findings provide a new theoretical basis for the basic mechanism of aerobic exercise training in stroke,and provide translational medicine reference for rehabilitation training to improve the treatment of neurological dysfunction after stroke.