Effects of bone marrow mesenchymal stem cells on apoptosis relative proteins of cerebral tissue in brain ischemic rat

Objective To observe the distribution of bone marrow mesenchymal stem cells(MSCs) and the effects on expression of apoptosis relative proteins Caspase 3 and Bcl-2 after intravenous transplanted into ischemic rat brains.Methods MSCs from SD rats were cultivated and proliferated in vitro and marked with CFSE.MSCs were then intravenously transplanted into middle cerebral artery occlusion(MCAO)models of SD rats.The rats were killed at different time points to observe the distribution of MSCs under fluorescence microscoDe as well as the effects on expression of apoptosis relative proteins Caspase 3 and Bcl-2 using immunohistochemical method.Results Density of Caspase 3 in immunohistochemically positive area in transplantion group were(2.81±0.35)%,(3.98±0.67)%,(5.58±0.92)%,(3.51±0.63)%,(1.64±0.29)%in 6,12,24,72 hours and in 7 days,respectively,and decreased significantly compared with those of control group[(3.92±0.44)%,(5.23±0.30)%,(6.89±0.57)%,(4.39±0.57)%,(2.29±0.21)%],the difference being significant(t=4.37,3.34,2.60,2.32,3.90,P＜0.05 or＜0.01).The density of Bcl-2 in immunohistochemically positive area in transplantation group were(4.70±0.16)%,(5.61±0.26)%,(3.00±0.28)%respectively in 6,12 hours and in 7 days,which had improved significantly compared with those of control group[(3.28±0.27)%,(4.54±0.59)%,(2.15±0.62)%],the difference being significant(t=8.32,3.25,2.54,P＜0.05 or＜0.01).Conclusions Bone marrow MSCs can exert protective effects on brain ischemia and reperfusion injury possibly by down-regulating Caspase 3 and up-regulating Bcl-2. Key words: Mesenchymal stem cells; Brain ischemia; Apoptosis