首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Edaravone has been shown to delay neuronal apoptosis, thereby improving nerve function and the microenvironment after spinal cord injury. Edaravone can provide a favorable environment for the treatment of spinal cord injury using Schwann cell transplantation. This study used rat models of complete spinal cord transection at T9. Six hours later, Schwann cells were transplanted in the head and tail ends of the injury site. Simultaneously, edaravone was injected through the caudal vein. Eight weeks later, the PKH-26-labeled Schwann cells had survived and migrated to the center of the spinal cord injury region in rats after combined treatment with edaravone and Schwann cells. Moreover, the number of PKH-26-labeled Schwann cells in the rat spinal cord was more than that in rats undergoing Schwann cell transplantation alone or rats without any treatment. Horseradish peroxidase retrograde tracing revealed that the number of horseradish peroxidase-positive nerve fibers was greater in rats treated with edaravone combined with Schwann cells than in rats with Schwann cell transplantation alone. The results demonstrated that lower extremity motor function and neurophysiological function were better in rats treated with edaravone and Schwann cells than in rats with Schwann cell transplantation only. These data confirmed that Schwann cell transplantation combined with edaravone injection promoted the regeneration of nerve fibers of rats with spinal cord injury and improved neurological function.  相似文献   

2.
Propofol is a neuroprotective anesthetic. Whether propofol can promote spinal cord injury repair by bone marrow mesenchymal stem cells remains poorly understood. We used rats to investigate spinal cord injury repair using bone marrow mesenchymal stem cell transplantation combined with propofol administration via the tail vein. Rat spinal cord injury was clearly alleviated; a large number of newborn non-myelinated and myelinated nerve fibers appeared in the spinal cord, the numbers of CM-Dil-labeled bone marrow mesenchymal stem cells and fluorogold-labeled nerve fibers were increased and hindlimb motor function of spinal cord-injured rats was markedly improved. These improvements were more prominent in rats subjected to bone marrow mesenchymal cell transplantation combined with propofol administration than in rats receiving monotherapy. These results indicate that propofol can enhance the therapeutic effects of bone marrow mesenchymal stem cell transplantation on spinal cord injury in rats.  相似文献   

3.
The repair effects of bone marrow mesenchymal stem cell transplantation on nervous system damage are not satisfactory. Propofol has been shown to protect against spinal cord injury. Therefore, this study sought to explore the therapeutic effects of their combination on spinal cord injury. Rat models of spinal cord injury were established using the weight drop method. Rats were subjected to bone marrow mesenchymal stem cell transplantation via tail vein injection and/or propofol injection via tail vein using an infusion pump. Four weeks after cell transplantation and/or propofol treatment, the cavity within the spinal cord was reduced. The numbers of PKH-26-positive cells and horseradish peroxidase-positive nerve fibers apparently increased in the spinal cord. Latencies of somatosensory evoked potentials and motor evoked potentials in the hindlimb were noticeably shortened, amplitude was increased and hindlimb motor function was obviously improved. Moreover, the combined effects were better than cell transplantation or propofol injection alone. The above data suggest that the combination of propofol injection and bone marrow mesenchymal stem cell transplantation can effectively improve hindlimb electrophysiological function, promote the recovery of motor funtion, and play a neuroprotective role in spinal cord injury in rats.  相似文献   

4.
Axonal regeneration and fiber regrowth is limited in the adult central nervous system, but research over the last decades has revealed a high intrinsic capacity of brain and spinal cord circuits to adapt and reorganize after smaller injuries or denervation. Short-distance fiber growth and synaptic rewiring was found in cortex, brain stem and spinal cord and could be associated with restoration of sensorimotor functions that were impaired by the injury. Such processes of structural plasticity were initially observed in the corticospinal system following spinal cord injury or stroke, but recent studies showed an equally high potential for structural and functional reorganization in reticulospinal, rubrospinal or propriospinal projections. Here we review the lesion-induced plastic changes in the propriospinal pathways, and we argue that they represent a key mechanism triggering sensorimotor recovery upon incomplete spinal cord injury. The formation or strengthening of spinal detour pathways bypassing supraspinal commands around the lesion site to the denervated spinal cord were identified as prominent neural substrate inducing substantial motor recovery in different species from mice to primates. Indications for the existence of propriospinal bypasses were also found in humans after cortical stroke. It is mandatory for current research to dissect the biological mechanisms underlying spinal circuit remodeling and to investigate how these processes can be stimulated in an optimal way by therapeutic interventions(e.g., fiber-growth enhancing interventions, rehabilitation). This knowledge will clear the way for the development of novel strategies targeting the remarkable plastic potential of propriospinal circuits to maximize functional recovery after spinal cord injury.  相似文献   

5.
An important factor in improving functional recovery from spinal cord injury using stem cells is maximizing the number of transplanted cells at the lesion site. Here, we established a contusion model of spinal cord injury by dropping a weight onto the spinal cord at T7–8. Superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells were transplanted into the injured spinal cord via the subarachnoid space. An outer magnetic field was used to successfully guide the labeled cells to the lesion site. Prussian blue staining showed that more bone marrow mesenchymal stem cells reached the lesion site in these rats than in those without magnetic guidance or superparamagnetic iron oxide labeling, and immunofluorescence revealed a greater number of complete axons at the lesion site. Moreover, the Basso, Beattie and Bresnahan(BBB) locomotor rating scale scores were the highest in rats with superparamagnetic labeling and magnetic guidance. Our data confirm that superparamagnetic iron oxide nanoparticles effectively label bone marrow mesenchymal stem cells and impart sufficient magnetism to respond to the external magnetic field guides. More importantly, superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells can be dynamically and non-invasively tracked in vivo using magnetic resonance imaging. Superparamagnetic iron oxide labeling of bone marrow mesenchymal stem cells coupled with magnetic guidance offers a promising avenue for the clinical treatment of spinal cord injury.  相似文献   

6.
We examined the restorative effect of modified biodegradable chitin conduits in combination with bone marrow mesenchymal stem cell transplantation after right spinal cord hemisection injury. Immunohistochemical staining revealed that biological conduit sleeve bridging reduced glial scar formation and spinal muscular atrophy after spinal cord hemisection. Bone marrow mesenchymal stem cells survived and proliferated after transplantation in vivo, and differentiated into cells double-positive for S100(Schwann cell marker) and glial fibrillary acidic protein(glial cell marker) at 8 weeks. Retrograde tracing showed that more nerve fibers had grown through the injured spinal cord at 14 weeks after combination therapy than either treatment alone. Our findings indicate that a biological conduit combined with bone marrow mesenchymal stem cell transplantation effectively prevented scar formation and provided a favorable local microenvironment for the proliferation, migration and differentiation of bone marrow mesenchymal stem cells in the spinal cord, thus promoting restoration following spinal cord hemisection injury.  相似文献   

7.
Clinical studies have shown that hyperbaric oxygen therapy improves motor function in patients with spinal cord injury. In the present study, we explored the mechanisms associated with the recovery of neurological function after hyperbaric oxygen therapy in a rat model of spinal cord injury. We established an acute spinal cord injury model using a modification of the free-falling object method, and treated the animals with oxygen at 0.2 MPa for 45 minutes, 4 hours after injury. The treatment was administered four times per day, for 3 days. Compared with model rats that did not receive the treatment, rats exposed to hyperbaric oxygen had fewer apoptotic cells in spinal cord tissue, lower expression levels of aquaporin 4/9 mRNA and protein, and more NF-200 positive nerve fibers. Furthermore, they had smaller spinal cord cavities, rapid recovery of somatosensory and motor evoked potentials, and notably better recovery of hindlimb motor function than model rats. Our findings indicate that hyperbaric oxygen therapy reduces apoptosis, downregulates aquaporin 4/9 mRNA and protein expression in injured spinal cord tissue, improves the local microenvironment for nerve regeneration, and protects and repairs the spinal cord after injury.  相似文献   

8.
Bacterial melanin, obtained from the mutant strain of Bacillus Thuringiensis, has been shown to promote recovery after central nervous system injury. It is hypothesized, in this study, that bacterial melanin can promote structural and functional recovery after peripheral nerve injury. Rats subjected to sciatic nerve transection were intramuscularly administered bacterial melanin. The sciatic nerve transected rats that did not receive intramuscular administration of bacterial melanin served as controls. Behavior tests showed that compared to control rats, the time taken for instrumental conditioned reflex recovery was significantly shorter and the ability to keep the balance on the rotating bar was significantly better in bacterial melanin-treated rats. Histomorphological tests showed that bacterial melanin promoted axon regeneration after sciatic nerve injury. These findings suggest that bacterial melanin exhibits neuroprotective effects on injured sciatic nerve, contributes to limb motor function recovery, and therefore can be used for rehabilitation treatment of peripheral nerve injury.  相似文献   

9.
A variety of inflammatory cytokines are involved in spinal cord injury and influence the recovery of neuronal function. In the present study, we established a rat model of acute spinal cord injury by cerclage. The cerclage suture was released 8 or 72 hours later, to simulate decompression surgery. Neurological function was evaluated behaviorally for 3 weeks after surgery, and tumor necrosis factor α immunoreactivity and apoptosis were quantified in the region of injury. Rats that underwent decompression surgery had significantly weaker immunoreactivity of tumor necrosis factor α and significantly fewer apoptotic cells, and showed faster improvement of locomotor function than animals in which decompression surgery was not performed. Decompression at 8 hours resulted in significantly faster recovery than that at 72 hours. These data indicate that early decompression may improve neurological function after spinal cord injury by inhibiting the expression of tumor necrosis factor α.  相似文献   

10.
The protective effects of erythropoietin on spinal cord injury have not been well described. Here, the eukaryotic expression plasmid pc DNA3.1 human erythropoietin was transfected into rat neural stem cells cultured in vitro. A rat model of spinal cord injury was established using a free falling object. In the human erythropoietin-neural stem cells group, transfected neural stem cells were injected into the rat subarachnoid cavity, while the neural stem cells group was injected with non-transfected neural stem cells. Dulbecco's modified Eagle's medium/F12 medium was injected into the rats in the spinal cord injury group as a control. At 1–4 weeks post injury, the motor function in the rat lower limbs was best in the human erythropoietin-neural stem cells group, followed by the neural stem cells group, and lastly the spinal cord injury group. At 72 hours, compared with the spinal cord injury group, the apoptotic index and Caspase-3 gene and protein expressions were apparently decreased, and the bcl-2 gene and protein expressions were noticeably increased, in the tissues surrounding the injured region in the human erythropoietin-neural stem cells group. At 4 weeks, the cavities were clearly smaller and the motor and somatosensory evoked potential latencies were remarkably shorter in the human erythropoietin-neural stem cells group and neural stem cells group than those in the spinal cord injury group. These differences were particularly obvious in the human erythropoietin-neural stem cells group. More CM-Dil-positive cells and horseradish peroxidase-positive nerve fibers and larger amplitude motor and somatosensory evoked potentials were found in the human erythropoietin-neural stem cells group and neural stem cells group than in the spinal cord injury group. Again, these differences were particularly obvious in the human erythropoietin-neural stem cells group. These data indicate that transplantation of erythropoietin gene-modified neural stem cells into the subarachnoid cavity to help repair spinal cord injury and promote the recovery of spinal cord function better than neural stem cell transplantation alone. These findings may lead to significant improvements in the clinical treatment of spinal cord injuries.  相似文献   

11.
Hydrogen can relieve tissue-damaging oxidative stress, inflammation and apoptosis. Injection of hydrogen-rich saline is an effective method for transporting molecular hydrogen. We hypothesized that hydrogen-rich saline would promote the repair of spinal cord injury induced by Allen''s method in rats. At 0.5, 1, 2, 4, 8, 12 and 24 hours after injury, then once daily for 2 weeks, 0.25 mL/kg hydrogen-rich saline was infused into the subarachnoid space through a catheter. Results at 24 hours, 48 hours, 1 week and 2 weeks after injury showed that hydrogen-rich saline markedly reduced cell death, inflammatory cell infiltration, serum malondialdehyde content, and caspase-3 immunoreactivity, elevated serum superoxide dismutase activity and calcitonin gene-related peptide immunoreactivity, and improved motor function in the hindlimb. The present study confirms that hydrogen-rich saline injected within 2 weeks of injury effectively contributes to the repair of spinal cord injury in the acute stage.  相似文献   

12.
The mechanism involved in neural regeneration after spinal cord injury is unclear. The myelin-derived protein Nogo-A, which is specific to the central nervous system, has been identified to negatively affect the cytoskeleton and growth program of axotomized neurons. Studies have shown that Nogo-A exerts immediate and chronic inhibitory effects on neurite outgrowth. In vivo, inhibitors of Nogo-A have been shown to lead to a marked enhancement of regenerative axon extension. We established a spinal cord injury model in rats using a free-falling weight drop device to subsequently investigate Nogo-A expression. Nogo-A mR NA and protein expression and immunoreactivity were detected in spinal cord tissue using real-time quantitative PCR, immunohistochemistry and western blot analysis. At 24 hours after spinal cord injury, Nogo-A protein and mR NA expression was low in the injured group compared with control and sham-operated groups. The levels then continued to drop further and were at their lowest at 3 days, rapidly rose to a peak after 7 days, and then gradually declined again after 14 days. These changes were observed at both the mR NA and protein level. The transient decrease observed early after injury followed by high levels for a few days indicates Nogo-A expression is time dependent. This may contribute to the lack of regeneration in the central nervous system after spinal cord injury. The dynamic variation of Nogo-A should be taken into account in the treatment of spinal cord injury.  相似文献   

13.
Paired immunoglobulin-like receptor B(Pir B) is a functional receptor of myelin-associated inhibitors for axonal regeneration and synaptic plasticity in the central nervous system, and thus suppresses nerve regeneration. The regulatory effect of Pir B on injured nerves has received a lot of attention. To better understand nerve regeneration inability after spinal cord injury, this study aimed to investigate the distribution of Pir B(via immunofluorescence) in the central nervous system and peripheral nervous system 10 days after injury. Immunoreactivity for Pir B increased in the dorsal root ganglia, sciatic nerves, and spinal cord segments. In the dorsal root ganglia and sciatic nerves, Pir B was mainly distributed along neuronal and axonal membranes. Pir B was found to exhibit a diffuse, intricate distribution in the dorsal and ventral regions. Immunoreactivity for Pir B was enhanced in some cortical neurons located in the bilateral precentral gyri. Overall, the findings suggest a pattern of Pir B immunoreactivity in the nervous system after unilateral spinal transection injury, and also indicate that Pir B may suppress repair after injury.  相似文献   

14.
Spinal cord injury results in the permanent loss of function, causing enormous personal, social and economic problems. Even though neural regeneration has been proven to be a natural mechanism, central nervous system repair mechanisms are ineffective due to the imbalance of the inhibitory and excitatory factors implicated in neuroregeneration. Therefore, there is growing research interest on discovering a novel therapeutic strategy for effective spinal cord injury repair. To this direction, cell-based delivery strategies, biomolecule delivery strategies as well as scaffold-based therapeutic strategies have been developed with a tendency to seek for the answer to a combinatorial approach of all the above. Here we review the recent advances on regenerative/neural engineering therapies for spinal cord injury, aiming at providing an insight to the most promising repair strategies, in order to facilitate future research conduction.  相似文献   

15.
Resistance mechanisms of rho-associated kinase (ROCK) inhibitors are associated with the enhanced expression of cyclooxygenase-2 (COX-2). The therapeutic effects of ROCK on nervous system diseases might be enhanced by COX-2 inhibitors. This study investigated the synergistic effect of the combined use of the ROCK inhibitor fasudil and a COX-2 inhibitor celecoxib on spinal cord injury in a rat model established by transecting the right half of the spinal cord at T11. Rat models were orally administrated with celecoxib (20 mg/kg) and/or intramuscularly with fasudil (10 mg/kg) for 2 weeks. Results demonstrated that the combined use of celecoxib and fasudil significantly decreased COX-2 and Rho kinase II expression surrounding the lesion site in rats with spinal cord injury, improved the pathomorphology of the injured spinal cord, and promoted the recovery of motor function. Moreover, the effects of the drug combination were better than celecoxib or fasudil alone. This study demonstrated that the combined use of fasudil and celecoxib synergistically enhanced the functional recovery of injured spinal cord in rats.  相似文献   

16.
Saponins extracted from Panax notoginseng are neuroprotective, but the mechanisms underlying this effect remain unclear. In the present study, we established a rat model of thoracic(T10) spinal cord transection, and injected Panax notoginseng saponins(100 mg/kg) or saline 30 minutes after injury. Locomotor functions were assessed using the Basso, Beattie, and Bresnahan(BBB) scale from 1 to 30 days after injury, and immunohistochemistry was carried out in the ventral horn of the spinal cord at 1 and 7 days to determine expression of nerve growth factor(NGF) and brain-derived neurotrophic factor(BDNF). Our results show that at 7–30 days post injury, the BBB score was higher in rats treated with Panax notoginseng saponins than in those that received saline. Furthermore, at 7 days, more NGF- and BDNF-immunoreactive neurons were observed in the ventral horn of the spinal cord of rats that had received Panax notoginseng saponins than in those that received saline. These results indicate that Panax notoginseng saponins caused an upregulation of NGF and BDNF in rats with spinal cord transection, and improved hindlimb motor function.  相似文献   

17.
Diffusion tensor imaging is a sensitive way to reflect axonal necrosis and degeneration, glial cell regeneration and demyelination following spinal cord injury, and to display microstructure changes in the spinal cord in vivo. Diffusion tensor imaging technology is a sensitive method to diagnose spinal cord injury; fiber tractography visualizes the white matter fibers, and directly displays the structural integrity and resultant damage of the fiber bundle. At present, diffusion tensor imaging is restricted to brain examinations, and is rarely applied in the evaluation of spinal cord injury. This study aimed to explore the fractional anisotropy and apparent diffusion coefficient of diffusion tensor magnetic resonance imaging and the feasibility of diffusion tensor tractography in the evaluation of complete spinal cord injury in rats. The results showed that the average combined scores were obviously decreased after spinal cord transection in rats, and then began to increase over time. The fractional anisotropy scores after spinal cord transection in rats were significantly lower than those in normal rats(P 0.05); the apparent diffusion coefficient was significantly increased compared with the normal group(P 0.05). Following spinal cord transection, fractional anisotropy scores were negatively correlated with apparent diffusion coefficient values(r = –0.856, P 0.01), and positively correlated with the average combined scores(r = 0.943, P 0.01), while apparent diffusion coefficient values had a negative correlation with the average combined scores(r = –0.949, P 0.01). Experimental findings suggest that, as a non-invasive examination, diffusion tensor magnetic resonance imaging can provide qualitative and quantitative information about spinal cord injury. The fractional anisotropy score and apparent diffusion coefficient have a good correlation with the average combined scores, which reflect functional recovery after spinal cord injury.  相似文献   

18.
The signaling mechanisms underlying ischemia-induced nerve cell apoptosis are poorly understood. We investigated the effects of apoptosis-related signal transduction pathways following ischemic spinal cord injury, including extracellular signal-regulated kinase (ERK), serine-threonine protein kinase (Akt) and c-Jun N-terminal kinase (JNK) signaling pathways. We established a rat model of acute spinal cord injury by inserting a catheter balloon in the left subclavian artery for 25 minutes. Rat models exhibited notable hindlimb dysfunction. Apoptotic cells were abundant in the anterior horn and central canal of the spinal cord. The number of apoptotic neurons was highest 48 hours post injury. The expression of phosphorylated Akt (p-Akt) and phosphorylated ERK (p-ERK) increased immediately after reperfusion, peaked at 4 hours (p-Akt) or 2 hours (p-ERK), decreased at 12 hours, and then increased at 24 hours. Phosphorylated JNK expression reduced after reperfusion, increased at 12 hours to near normal levels, and then showed a downward trend at 24 hours. Pearson linear correlation analysis also demonstrated that the number of apoptotic cells negatively correlated with p-Akt expression. These findings suggest that activation of Akt may be a key contributing factor in the delay of neuronal apoptosis after spinal cord ischemia, particularly at the stage of reperfusion, and thus may be a target for neuronal protection and reduction of neuronal apoptosis after spinal cord injury.  相似文献   

19.
高压氧联合神经干细胞移植治疗大鼠脊髓损伤   总被引:1,自引:0,他引:1  
背景:单纯神经干细胞移植已应用于对受损脊髓组织的修复。 目的:以神经干细胞移植同时应用高压氧治疗大鼠脊髓损伤,观察联合作用对脊髓损伤大鼠运动功能恢复的影响。 方法:雌性SD大鼠60只,以半切法制成胸段脊髓半横断大鼠模型。随机分成单纯损伤组、神经干细胞移植组及高压氧治疗组,每组20只。伤后第4周取材行病理切片苏木精-伊红染色及BrdU免疫组织化学染色,第8周取材行辣根过氧化物酶示踪,透射电镜观察轴突的再生情况,通过体感诱发电位观察神经电生理恢复情况。造模后1,2,4,6,8周进行BBB评分和斜板实验等运动功能检测。 结果与结论:观察伤后4周病理切片,单纯损伤组未见神经轴索通过,神经干细胞移植组可见少量神经轴索样结构,高压氧治疗组可见较多神经轴索样结构。BrdU的阳性细胞数及辣根过氧化物酶阳性神经纤维数,高压氧治疗组最多,神经干细胞移植组次之,单纯损伤组最少,且各组之间差异有显著性意义(P < 0.05)。透射电镜下神经干细胞移植组、高压氧治疗组正中横断面可见新生的无髓及有髓神经纤维。高压氧治疗组大鼠体感诱发电位的潜伏期短于神经干细胞移植组,波幅高于神经干细胞移植组(P < 0.05),明显优于单纯损伤组(P < 0.01)。伤后4周神经干细胞移植组、高压氧治疗组大鼠后肢运动功能均有较明显恢复,高压氧治疗组较神经干细胞移植组恢复快(P < 0.05);单纯损伤组亦有所恢复,但程度较轻。提示神经干细胞移植对于脊髓损伤大鼠后肢功能的恢复有促进作用,联合应用高压氧有协同效果。  相似文献   

20.
Previous studies have shown that the neurite growth inhibitor Nogo-A can cause secondary neural damage by activating Rho A. In the present study, we hypothesized that electroacupuncture promotes neurological functional recovery after spinal cord injury by inhibiting Rho A expression. We established a rat model of acute spinal cord injury using a modification of Allen's method. The rats were given electroacupuncture treatment at Dazhui(Du14), Mingmen(Du4), Sanyinjiao(SP6), Huantiao(GB30), Zusanli(ST36) and Kunlun(BL60) acupoints with a sparsedense wave at a frequency of 4 Hz for 30 minutes, once a day, for a total of 7 days. Seven days after injury, the Basso, Beattie and Bresnahan(BBB) locomotor scale and inclined plane test scores were significantly increased, the number of apoptotic cells in the spinal cord tissue was significantly reduced, and Rho A and Nogo-A m RNA and protein expression levels were decreased in rats given electroacupuncture compared with rats not given electroacupuncture. Four weeks after injury, pathological tissue damage in the spinal cord at the site of injury was alleviated, the numbers of glial fibrillary acidic protein- and neurofilament 200-positive fibers were increased, the latencies of somatosensory-evoked and motor-evoked potentials were shortened, and their amplitudes were increased in rats given electroacupuncture. These findings suggest that electroacupuncture treatment reduces neuronal apoptosis and decreases Rho A and Nogo-A m RNA and protein expression at the site of spinal cord injury, thereby promoting tissue repair and neurological functional recovery.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号