The Neuroprotective Effects Of Inhibition Of Phactr-1PHACTR-1 Protein Expression After Traumatic Brain Injury And Studys Of Mechanisms

Aim: Phosphatase actin regulator-1(PHACTR-1)is a binding protein that regulates actin and protein phosphatase 1,and is expressed in neurons and endothelial cells of brain tissue.Studies had found that the elevated expression of PHACTR-1 could induce subarachnoid hemorrhage and stroke,however,the changes and effects of PHACTR-1 expression after traumatic brain injury(TBI)were unknown.In order to further determine the relationship,we explored the effects of PHACTR-1 protein on neural function after TBI and its specific molecular biological mechanism by establishing animal and in vitro cell injury models.Method: Controlled cortex impact(CCI)model were established in C57 BL / 6 mice to detect the changes of PHACTR-1 protein expression and cell localization.Using three points of subcortical injection of adeno-associated virus,the PHACTR-1 protein was overexpressed and knockdown.Brain water content was determined its protective effect,followed by extravasation of Evans Blue,losses of tight junction protein,expressions of AQP-4 and ICAM-1,the number of activated astrocytes,the typing of microglia,the detection of inflammation-related factors and neuronal apoptosis.At the same time,it was determined the effect of PHACTR-1 protein on the NF-?B signaling pathway.m NSS,rotarod test and water maze test were used to detect the changes of neurological deficits after TBI by the PHACTR-1 protein.Bend.3,HT22 and BV2 cell lines were transfected with lentivirus in vitro,and the models of stretch injury and inflammation inductions were performed to detect the effect of PHACTR-1protein on apoptosis and inflammation-related factors after injury.Result: After the CCI model establishment,the expression of PHACTR-1 protein in brain tissue was increased,and found on endothelial cells,neurons,astrocytes,and microglia.Overexpression of PHACTR-1 protein increased the water content in the brain tissue.After knocking down PHACTR-1 protein,the water content in the brain tissue was decreased.Inhibition of the expression of PHACTR-1 protein could regulate the NF-?B signaling pathway to reduce extravasation of Evans Blue,losses of tight junction proteins,expressions of AQP-4 and ICAM-1,astrocytes and microglia-related neuroinflammation,and apoptosis of nerve cells,thereby improving neurological deficits.In vitro experiments,inhibition of the expression of PHACTR-1protein could reduce the apoptosis of bEnd.3 and HT22 after injury,as well as the expressions of pro-inflammatory factors and increase the expressions of anti-inflammatory factors after activations of BV2 cell inflammation model.Conclusion: Inhibition of PHACTR-1 protein expression in mouse brain tissue could change some pathophysiological damages and reduce neurological deficits after TBI.The results had been further verified in vitro experiments.Therefore,inhibition of PHACTR-1 protein may be a new target for the treatment of TBI.