Spatial-temporal Expression Of NDRG2 In Traumatic Brain Injury Mouse And Its Latent Clinical Value

Part?:Spatial-temporal expression of NDRG2 in mouse brain after traumatic brain injuryObjective:To explore the spatial-temporal expression of NDRG2 in mouse brain after traumatic brain injury(TBI)as well as the relationship with cell apoptosis.Materials and methods:Mice(male ICR)TBI model was induced using a modified weight-drop method.The mice were randomly devided into the following groups:sham,TBI6h,TBI 12h,TBI 24h,TBI 48h,TBI 72h,TBI 7day.Western blot was used to detect the changes of NDRG2 levels in the brain samples surrounding the injury site.Immunofluorescence was used to explore the cellular and subcellular locations of NDRG2 as well as its relationship with apoptosis.Results:The results showed that the levels of NDRG2 protein increased significantly from12 hours after TBI,peaked at 24 hours,and gradually declined within a week.The results of immunofluorescence showed that NDRG2 signals were specifically located in astrocytes.Besides,a significant translocation of NDRG2 from cytoplasm to nucleus and a significant increase in number of NDRG2/TUNEL double positive cells were observed after TBI.Conclusion:NDRG2 protein levels significantly increased after TBI from 12h and peaked at24h.NDRG2 proteins were specifically located in astrocytes and its increased protein levels associated with cell apoptosis.These findings indicated that NDRG2 may be involved with apoptosis.Part?:The rise of serum NDRG2 correlates with poor outcome of traumatic brain injury patientsObjective:To investigate the change and clinical significance of serum NDRG2 levels in traumatic brain injury(TBI)patients.Materials and methods:A prospective control study which enrolled 41 TBI patients and 39heathy controls was carried out.Serum samples were collected on day 1?day 2-4?day 5-7after TBI,respectively.Serum NDRG2 levels were measured using commercial ELISA kit.Clinical data of patients were also collected for statistical analysis.Results:1)Compared with healthy controls,serum NDRG2 levels were significantly higher on day 1,day 2-4,day 5-7 after TBI,respectively(p<0.05).2)The results of Spearman linear correlation analysis showed that the serum NDRG2 levels on day 1 correlated with GCS score(r_s=-0.388,p=0.012),pupil response(r_s=0.392,p=0.011),GOS score(r_s=-0.371,p=0.017).3)The results of binary logistic regression showed that the serum NDRG2 level on day 1 was an independent risk factor for poor prognosis of TBI patients.Conclusion:Serum NDRG2 levels correlated with the severity of TBI patients.Besides,the serum NDRG2 level on day 1 after TBI was an independent risk factor for poor prognosis.These findings provide latent clinical value for prognosis evaluation of TBI patients.