Poly-lactic acid and agarose gelatin play an active role in the recovery of spinal cord injury

Objective To investigate the role of poly-lactic acid and agarose gelatin in promoting the functional recovery of the injured spinal cord. Methods Poly-lactic acid ( PLA) or agarose was embedded in the space between two stumps of the hemisectioned spinal cord. Immunohistochemistry was used to show astroglia proliferation and the infiltration of RhoA-positive cells. Locomotor activity recovery was evaluated by testing the function of hindlimbs. Results Astrogli-as and RhoA labeled non-neuronal cells accumulated in the area adjacent to the implant, while the number of RhoA-positive cells was decreased dramatically in the absence of implant. Animals implanted with agarose gelatin recovered more quickly than those with PLA, concomitant with a higher survival rate of the neurons. Conclusion Both PLA and agarose gelatin benefited the recovery of spinal cord after injury by providing a scaffold for astroglia processes. Modulation of the rigidity, pore size and inner structure of PLA and agarose gelatin might make these biodegradable materials more effective in the regeneration of the central nervous system (CNS).

针刺通过增加前额叶皮层突触蛋白的表达对两种抑郁症动物模型的快速抗抑郁作用

Objective:To investigate the effect of acupuncture onset time and synaptic structure in two different models of depression.Methods:A total of 150 healthy male adult SPF C57BL/6J mice were divided into five time-point groups:1 h,3 h,6 h,12 h and 24 h.Each time-point group was further divided into three groups:the model,scopolamine and acupuncture groups with 10 rats each.Rats were given forced swimming stimulation(15 min,once)before the intervention.A total of 200 healthy male adult specific pathogen-free(SPF)Sprague-Dawley(SD)rats were divided into 30 normal rats,and 170 modelling ones.A total of 90 rats were successfully modeled,and were randomly divided into three time-point groups:1 h,6 h and 24 h.And each time-point group was further divided into the normal,model,scopolamine,and acupuncture group.Chronic unpredictable mild stress(CUMS)combined with individual feeding was used to establish the depressed rat model.The sucrose preference test(SPT)and open field test(OFT)were used to evaluate the success of the model.There were 10 rats in each group.The acupuncture intervention was performed once for 20 min on"Baihui(GV20)","Yintang(GV29)","Hegu(LI4)",and"Taichong(LR3)"without any other operations for the corresponding animals.Other groups were given corresponding medications.According to different time points,the forced swimming test(FST)was conducted in mice,and the FST and novelty-suppressed feeding test(NSFT)were measured in rats.Monoamine neurotransmitters(NE,DA,DOPAC,5-HT,5-HIAA,HVA)in the prefrontal cortex and hippocampus were detected with high performance liquid chromatography(HPLC).The expression of synapsin I,PSD95,p-mTOR,mTOR,and BDNF in the prefrontal cortex and hippocampus was determined by western blot.Results:At the 1 h time point,compared with the model group,the immobility time was significantly decreased in the acupuncture group(P<0.05).At 3 h,6 h,12 h,and 24 h,compared with the model group,the immobility time was significantly reduced in both scopolamine and acupuncture groups(P<0.05).At the 1 h time point,compared with the normal group,the immobility time of FST and the latency to feed were significantly increased in the model group(P<0.05).Compared with the model group,the immobility time of FST showed a significant reduction in the acupuncture group(P<0.05).At the 6h and 24 h time points,compared with the normal group,the immobility time of FST and the latency to feed were significantly increased in the model group(P<0.05).Compared with the model group,the immobility time of FST was significantly decreased in the scopolamine and acupuncture groups(P<0.05).At the 1 h and 24 h time points,compared with the normal group,the expression levels of 5-HT,5-HIAA,NE,DA,DOPAC,and HVA of the prefrontal cortical and hippocampal tissues were significantly reduced in the model group(P<0.05).At the 1 h and 24 h time points,compared with the model group,the expression levels of synapsin I,PSD95,p-mTOR,and BDNF of the prefrontal cortex were significantly increased in the acupuncture group(P<0.05).At the 1 h and 24 h time points,compared with the normal group,the expression levels of synapsin I,PSD95,p-mTOR,and BDNF of the prefrontal cortex were significantly reduced in the model group(P<0.05).Compared with the model group,the expression levels of synapsin I,PSD95,p-mTOR,and BDNF of the prefrontal cortex were significantly increased in the acupuncture group(P<0.05).At the 1 h and 24 h time points,compared with the normal group,the expression levels of synapsin I,PSD95,p-mTOR,and BDNF of the hippocampal tissues were significantly reduced in the model group(P<0.05).Compared with the model group,the expression levels of synapsin I,PSD95,p-mTOR,and BDNF of the hippocampus were not significantly different in the acupuncture group(P>0.05).Conclusion:Acupuncture may play a rapid antidepressant effect by increasing the expression of synaptic plasticity proteins in the prefrontal cortex.