The Study Of BMSCs Graft In Combination With VEGF On The Nerve Cells Apoptosis And The Neural Functional Recovery After Spinal Cord Injury In Rats

Objective: To explore the effect of marrow-derived mesenchymal stem cells (BMSCs)transplantation in combination with repeated intrathecal injection of vascularendothelial growth factor (VEGF) on nerve cells apoptosis and repair of spinal cordinjury after acute spinal cord injury in rats.Methods：Using the method of density gradient centrifugation to get rat BMSCs.Selection of140adult health Sprague-Dawley (SD) rats,weight200-250g,all are male.Establishing the model of spinal cord injury (SCI) in SD rats by compressive clampon thoracic10spinal cord. Create operation control group (group A), BMSCstransplantation group (group B), VEGF group (group C), BMSCs transplantationcombined with VEGF group (group D), randomly assigned only35rats in each group.Randomly select5rats from each group,1d before surgery, postoperative1d,3d,7d,14d and21d and28d, adopting the double-blind rating of BBB movement functiontests, and for28days after spinal cord injury, adopting the method ofimmunohistochemical staining to detcet NF200changes.Then according to theobservation time point, divide each group into postoperative4h,8h,1d,3d,7d,14d group, randomly assigned only5in each group. In postoperative4h,8h,1d,3d,7dand14d to take out the damage segmental spinal cord tissue,using the method ofRT-PCR to detect gene expression changes of bax and bcl-2, at each time point fiverats. By way of the analysis of variance and LSD-t test for statistical annalysis toprocess the acquired data.Results：(1)The cells derived from density gradient centrifugation can subculture andamplification in ritro,using flow cytometry instrument testing confirmed that theacquied cells are rats BMSCs.(2)SD rats’s SCI models were successfully set up, BBBAtransplantation groups had no significant difference with that of normal groups(p>0.05),2w,3w, and4w point B、C and D was significantly higher than A,statistically significant differences(P<0.05); D was higher than B and C, there are significant difference(P<0.05).(3)After SCI,bax and bcl-2protein expression level ineach group were increased, but more increased in bax gene. Compared with group A,the bcl-2protein of group B and group C expresse more quantity(P<0.05), the baxprotein express less(P<0.05), the bcl-2protein expresse high quantity than group Band C(P<0.05),while bax protein expression decrease(P<0.05).(4)NFimmunohistochemical results confirm that the average grey balue butyl of group Dwas obviously lower than the other three groups, with a statistically significantdifference(P<0.05).Conclusion:(1)BMSCs and VEGF can promote the expression of NF, that wasbeneficial to the recovery of neural function;(2)BMSCs,VEGF by way of regulatingapoptosis gene bax and bcl-2to protect and promote the repair of SCI.(3)BMSCstransplantation combine application of VEGF can ptomote the repair of the acte SCI,and they have synergy, the effect of combination is superior to a single application.