Tetramethylpyrazine Promote Bone Marrow Mesenchymal Stem Cells Migration Into Ischemic Brain Tissue And Its Underlying Mechanisms

Objective To observe the effect of Tetramethylpyrazine promote bone marrow mesenchymal stem cells migration of cerebral ischemic boundary,and to explore its mechanism may be related to the SDF-1/CXCR4 axis.Methods(1)Isolated and cultured BMSCs by the whole bone marrow adherent method,at the third passage,conduct phenotypic identification using Flow cytometry analysis of surface positive antigen of CD29,CD90 and the negative antigen of CD34,CD45,before transplantation BMSCs by BrdU labeling.(2)Rats were subjected to middle cerebral artery occlusion(MCAO)for 90 minutes.sham group,model group,BMSCs group,TMP group(20 mg/kg of TMP and 40 mg/kg of TMP),combined group(20 mg/kg of TMP+BMSCs,40 mg/kg of TMP+BMSCs),n=12,were administered randomly 2 h after ischemia,TMP group and combined group were injected with TMP via intraperitoneal,once daily for 14 days.24 h after ischemia,the sham group and model group were injected with 1 mL PBS,BMSCs group and combined group were injected with rats BMSCs solution of 1 mL(1×106 cells)via the tail vein.(3)Modified neurological severity score(mNSS),adhensive removal test and the corner test were used to evaluate sensorimotor on 1,3,7and 14 days after ischemia.Fourteen days after ischemia,the volume of cerebral infarction were stained with toluidine blue.(4)Fourteen days after ischemia,the expression of BrdU of cerebral ischemia was detected by immunofluorescence.(5)Fourteen days after ischemia,the expression of SDF-1 and CXCR4 was detected by immunofluorescence,the expression of SDF-1,CXCR4 mRNA and protein was examined by real-time fluorescent quantitative PCR and Western blot.Results(1)The whole bone marrow adherent method can obtained the well-growing and get a homogeneous morphology BMSCs.The BMSCs phenotype of the third passage,the positive expression rates of CD29,CD90,CD34 and CD45 were 98.3%,99.5%,0.1%and 1.4%.It’s in line with the characteristics of BMSCs,confirmed the cells we separated were BMSCs.(2)Compared with the BMSCs group,combined group significantly ameliorated neurological dysfunction,the time of adhensive removal and the number of right turn significantly reduced at 3,7 and 14 days after ischemia(P<0.05 or P<0.01).Fourteen days after ischemia,the infarct volume significantly reduced(P<0.05 or P<0.01).(3)Fourteen days after ischemia,the number of BrdU was significantly increased(P<0.05 or P<0.01).(4)Fourteen days after ischemia,combined group the expression of SDF-1,CXCR4 mRNA and protein was significantly increased(P<0.05 or P<0.01).Conclusion(1)TMP and BMSCs combination treatment can improve neurological function and reduce the infarct volume in a rat model of cerebral ischemia.(2)TMP promote BMSCs migration into ischemic brain tissue.(3)TMP promote BMSCs migration into ischemic brain tissue may be related with up-regulated SDF-1/CXCR4 expression.