Electrical stimulation combined with neurotrophin 3 promotes proliferation and differentiation of endogenous neural stem cells after spinal cord injury in rats / 中国组织工程研究

ABSTRACT

BACKGROUND: Due to limited access to exogenous neural stem cells, immune rejection and ethical problems, how to activate endogenous neural stem cells and promote their growth, proliferation and differentiation has become an issue of concern. OBJECTIVE: To investigate the effects of electrical stimulation combined with neurotrophin 3 on the proliferation and differentiation of endogenous neural stem cells into neurons after spinal cord injury in rats. METHODS: Ninety-six rats were randomly divided into sham operation (spinal cord exposed only), spinal cord injury, electrical stimulation, and electrical stimulation+neurotrophin groups, 24 rats in each group. A rat model of spinal cord injury was established by modified Allen method in the latter three groups. After the model was established, the rats in the four groups were given corresponding treatments. At 7, 14, 21, and 28 days after modeling, the motor function of hind limbs was evaluated by Basso-Beattie-Bresnahan score. The latency of motor evoked potential was examined by electrophysiology. At 28 days after modeling, samples of the spinal cord were taken for hematoxylin-eosin staining to observe the pathological changes and for immunohistochemical staining to observe the the proliferation and differentiation of endogenous neural stem cells. The study was approved by the Ethics Committee of the Second Hospital of Lanzhou University. RESULTS AND CONCLUSION: (1) Compared with the sham operation group, the Basso-Beattie-Bresnahan score in the spinal cord injury group was significantly decreased (P electrical stimulation group > spinal cord injury group. The expression level of glial fibrillary acidic protein was highest in the spinal cord injury group, followed by electrical stimulation group, and lowest in the electrical stimulation+neurotrophin group. These results show that after electrical stimulation plus neurotrophin 3 intervention, endogenous neural stem cells can proliferate and differentiate into neurons. Pathological damage is significantly alleviated and motor function of hind limbs is significantly improved.