ABSTRACT
Objective To investigate the functional recovery and the effect of CNTF antibody block to the bone marrow mesenchymal stem cells (BMSCs) transplantated by Abdominal aortic on the downstream signaling pathways STAT3/Caspase-9 in spinal cord ischemic reperfusion injury in rats.Methods Adult female SD ratswere assigned randomly to 4 groups. The neurological functional status of the animals was assessed with BBB scores, the Motor evoked potentials (MEP) and Cortical somatosensory evoked potentials (CSEP).The IHC were used to detect the the expressional changes of CNTF, then Western blot and RT-PCR were used to detect the expressional changes of STAT3、p-STAT3、CNTF and Caspase-9 in the ischemic segments of spinal cord.Results Compared with the sham group, in the SCIRI rats, the BBB scores were markedly decreased at all time points (P＜0.01), the latency and the amplitude of MEP and CSEP was longer and lower at 14 d post operation (P＜0.01), and this change was the most significant in the control group the second in the CNTF block group, and the last in the transplantation group, Resutts between each two groups were statistically significant (P＜0.05). At 7 d post operation, compared with the sham group, the immunoreactive products of CNTF were decreased in the CNTF block group (P＜0.05), but were increased (P＜0.05) in the control group and the transplantation group (P＜0.05), and results in the transplantation group were higher than in the control group (P＜0.05). At 7 d post operation, compared with the sham group, the m RNA and protein level of CNTF、STAT3、 p-STAT3 were decreased obviously in CNTF block group (P＜0.05), the levels were increased in the control group and the transplantation group (P＜0.05), and the levels in the transplantation group were higher than that in the control group (P＜0.05); but the m RNA and protein level of Caspase-9 were only decreased in the transplantation group (P＜0.05), the level was increased in the CNTF block group and the control groups (P＜0.05), and the level in the CNTF block group was more significantly increased than that in the control group (P＜0.05). At 14 d post operation, in CNTF block group, the m RNA and protein level of CNTF、STAT3、p-STAT3 were significantly higher than that in the sham group and the control group (P＜0.05), and the m RNA and protein level of caspase-9 was higher than that in the sham group (P＜0.05), but lower than that in the control group (P＜0.05), there were not statistically different in the level of each factor compared with transplantation group (P＞0.05). Conclusions BMSCs, transplanted by the abdominal aorta, can promote the expression of CNTF in the injuried spinal cord and significantly improve the hind limb function recovery by CNTF-mediated signaling pathway downstream of STAT3/Caspase-9 SCIRI in rats, but the role of BMSCs can be weakening by CNTF block that inhibited STAT3/Caspase-9 signaling pathway.