Study On Schwann-Like Cell Conditioned Medium To Protect Neurons Against Cerebral Ischemia-Reperfusion Injury

BackgroundSchwann cells(SCs)involved in the formation of myelin sheath in peripheral nerves play an important role in neuronal survival and axon regeneration.After nerve injury,SCs form longitudinal continuous cell cords that guide axon regeneration by proliferating and migrating.In addition,SCs can also secrete some active factors,including nerve growth factor,neurotrophic factor and antioxidant enzymes,which can induce axon regeneration,promote neuronal survival and provide a good microenvironment for nerve regeneration.SCS derivatives may be an effective meterials for the treatment of ischemic stroke due to their high efficacy and safety.ObjectivesTo investigate the effect and mechanism of Schwann-like cell conditioned medium(SCLC-CM)on improving neurological function,alleviating tissue damage,inhibiting oxidative stress,cerebral infarction and cerebral edema,and improving neuronal survival after impairment of cerebral ischemia-reperfusion in rats.Methods(1)Human embryonic stem cell derived-neural stem cells(h ESC-NSCs)differentiated into Schwann-like cells(SCLCs)and SCLC-CM was collected by vacuum freeze-drying.(2)The damage model of cerebral ischemia-reperfusion was developed in rats and SCLC-CM was injected into brain by stereotaxic apparatus.(3)The neurological function of rats was assessed by neuroligical score and open field test.(4)Brain tissue injury was assessed by brain water content,infarct volume and neuronal apoptosis.(5)The oxygen-glucose deprivation(OGD)model was established in vitro,the levels of oxidative stress and cell apoptosis in PC12 cells were detected.(6)SCLC-CM was detected by mass spectrometry and bioinformatics analysis was performed on the data of mass spectrometry to predict the main functional protein of which exogenous recombinant protein and neutralizing antibody were used for verification.Results(1)SCLC-CM promoted the rehabilitation of neurological functions and alleviated the injury of brain tissue in rats with cerebral ischemia-reperfusion.(2)SCLC-CM reduced neuronal apoptosis and promoted axon regeneration in rats with cerebral ischemia-reperfusion.(3)SCLC-CM alleviated oxidative stress damage in OGD-induced PC12 cells.(4)SCLC-CM significantly reduced the cell apoptosis after OGD injury in PC12 cells.(5)Bioinformatics analysis of mass spectrometry revealed high enrichment of antioxidant enzymes in SCLC-CM.(6)The recombinant protein and neutralizing antibody of PRDX6 confirmed that PRDX6 functioned via regulating the PTEN/PI3K/ AKT pathway.Conclusions(1)SCLC-CM can reduce oxidative stress injury,inhibit neuronal apoptosis,and promote the recovery of neurological function.(2)SCLC-CM can inhibit neuronal apoptosis via scavenging ROS and activating the PTEN/PI3K/AKT pathway by antioxidant enzyme PRDX6.