scholarly journals Motor improvements enabled by spinal cord stimulation combined with physical training after spinal cord injury: review of experimental evidence in animals and humans

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Ismael Seáñez ◽  
Marco Capogrosso

AbstractElectrical spinal cord stimulation (SCS) has been gaining momentum as a potential therapy for motor paralysis in consequence of spinal cord injury (SCI). Specifically, recent studies combining SCS with activity-based training have reported unprecedented improvements in motor function in people with chronic SCI that persist even without stimulation. In this work, we first provide an overview of the critical scientific advancements that have led to the current uses of SCS in neurorehabilitation: e.g. the understanding that SCS activates dormant spinal circuits below the lesion by recruiting large-to-medium diameter sensory afferents within the posterior roots. We discuss how this led to the standardization of implant position which resulted in consistent observations by independent clinical studies that SCS in combination with physical training promotes improvements in motor performance and neurorecovery. While all reported participants were able to move previously paralyzed limbs from day 1, recovery of more complex motor functions was gradual, and the timeframe for first observations was proportional to the task complexity. Interestingly, individuals with SCI classified as AIS B and C regained motor function in paralyzed joints even without stimulation, but not individuals with motor and sensory complete SCI (AIS A). Experiments in animal models of SCI investigating the potential mechanisms underpinning this neurorecovery suggest a synaptic reorganization of cortico-reticulo-spinal circuits that correlate with improvements in voluntary motor control. Future experiments in humans and animal models of paralysis will be critical to understand the potential and limits for functional improvements in people with different types, levels, timeframes, and severities of SCI.

2019 ◽  
Vol 78 (6) ◽  
pp. 465-473 ◽  
Author(s):  
Mostafa Hosseini ◽  
Arash Sarveazad ◽  
Asrin Babahajian ◽  
Masoud Baikpour ◽  
Alexander R Vaccaro ◽  
...  

Abstract Context Many animal studies have evaluated the role of vitamins in the recovery of motor function after spinal cord injury, but their results have been contradictory and no consensus has been reached. Objective This meta-analysis aimed to investigate the effects of vitamin C and vitamin E on recovery of motor function after spinal cord injury in animal models. Data Sources Two authors independently collected the records of relevant articles published in MEDLINE, Embase, Scopus, and Web of Science through November 2018. Study Selection All studies conducted in animal models to evaluate the therapeutic effects of vitamin C or vitamin E or both on recovery of motor function after spinal cord injury were included. Studies that lacked a control group or a standard treatment, lacked an assessment of motor function, included genetically modified/engineered animals, included animals pretreated with vitamin C or vitamin E, or combined vitamin treatment with other methods, such as cell therapies, were excluded. Data Extraction Data from 10 articles met the inclusion criteria for meta-analysis, conducted in accordance with PRISMA guidelines. Results Daily supplementation with vitamin C (P < 0.0001) and vitamin E (P < 0.0001) significantly improved the recovery of motor function in animals affected by spinal cord injury. Vitamin C supplementation is effective only when administered intraperitoneally (P < 0.0001). Concurrent supplementation with both vitamins does not show better efficacy than treatment with either one alone. Conclusion Administration of vitamin C and vitamin E in animal models of spinal cord injury significantly improves the recovery of motor function.


Author(s):  
Mengdie Hu ◽  
Zhidong Cao ◽  
Dianming Jiang

Background: Spinal cord injury (SCI) is currently not completely curable. Exosomes have been widely used in preclinical studies of spinal cord injury. Here, in this meta-analysis, we focused on evaluating the overall efficacy of therapies based on miRNA-modified exosomes on functional recovery in animal models of SCI.Methods: PubMed, embase and Web of Science library databases were searched. Relevant literature was included, and the random effects model was used to assess the overall effect of the intervention, with outcomes expressed as SMD. The primary outcome included motor function scores. Risk of bias (ROB) was assessed using the ROB tool of the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE). R version 4.1.1software and Review Manager software were used for meta-analysis.Results: A total of 11 preclinical studies were included. The meta-analysis revealed that miRNA-modified exosome therapy was effective in improving motor function scores compared with exosomes alone or control therapy (standardized mean difference: 4.21; 95% confidence interval: 3.39–5.04). There was significant asymmetry in the funnel plot, and trim-and-fill analysis revealed four unpublished studies of motor scores. The quality of all included studies was evaluated with SYRCLE’s ROB tool. The SCI model, administration time and dose had an impact on the effect of the treatment.Conclusion: MiRNA-modified exosomes have shown great potential in the treatment of SCI. Moreover, the efficacy of miRNA-modified exosomes was superior to that of exosomes alone.


Author(s):  
Vladimir A. Smirnov ◽  
Sergey A. Bazanovich ◽  
Mikhail Ya. Yadgarov ◽  
Marina A. Zvyagintseva ◽  
Andrew A. Grin ◽  
...  

In the most of functional studies, various stress tests are used to assess functional improvement following spinal cord injury in animal models. However, available methods of motor function evaluation are not always accurate and unbiased. The main objective of the study was to create a new method of motor activity assessment in minor animal models of spinal cord injury. This method should provide an objective and accurate evaluation of limb motor function in models having severe neurological disorders following contusion spinal cord injury. The swimming test was used as the key behavioral test. To assess the motor function of swimming animals’ hind limbs, we measured angles of hind limbs movements adjusted to the motion direction axis. Then we calculated individual angles dispersion for each joint and limb using the parameters of angles sample dispersion and amplitude-depending dispersion. The current study included two groups of Sprague-Dawley rats: control group and a group of animals having moderate thoracic spinal cord contusion injury. Control animals demonstrated stable dispersion indicators for 6 weeks of follow-up. In the experimental group, a tendency to the improvement of motor function in hind limbs between 1 and 3 weeks was revealed followed by stabilization and preservation of both indicators between 3 and 6 weeks. Provided method based on the measurement of joint angles adjusted to the movement direction axis followed by calculation of indicators of variance of a random variable and amplitude-depending variance can be an effective and objective alternative for motor function evaluation.


2021 ◽  
pp. 096032712110033
Author(s):  
Liying Fan ◽  
Jun Dong ◽  
Xijing He ◽  
Chun Zhang ◽  
Ting Zhang

Spinal cord injury (SCI) is one of the most common destructive injuries, which may lead to permanent neurological dysfunction. Currently, transplantation of bone marrow mesenchymal stem cells (BMSCs) in experimental models of SCI shows promise as effective therapies. BMSCs secrete various factors that can regulate the microenvironment, which is called paracrine effect. Among these paracrine substances, exosomes are considered to be the most valuable therapeutic factors. Our study found that BMSCs-derived exosomes therapy attenuated cell apoptosis and inflammation response in the injured spinal cord tissues. In in vitro studies, BMSCs-derived exosomes significantly inhibited lipopolysaccharide (LPS)-induced PC12 cell apoptosis, reduced the secretion of pro-inflammatory factors including tumor necrosis factor (TNF)-α and IL (interleukin)-1β and promoted the secretion of anti-inflammatory factors including IL-10 and IL-4. Moreover, we found that LPS-induced protein expression of toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and nuclear transcription factor-κB (NF-κB) was significantly downregulated after treatment with BMSCs-derived exosomes. In in vivo studies, we found that hindlimb motor function was significantly improved in SCI rats with systemic administration of BMSCs-derived exosomes. We also observed that the expression of pro-apoptotic proteins and pro-inflammatory factors was significantly decreased, while the expression of anti-apoptotic proteins and anti-inflammatory factors were upregulated in SCI rats after exosome treatment. In conclusion, BMSCs-derived exosomes can inhibit apoptosis and inflammation response induced by injury and promote motor function recovery by inhibiting the TLR4/MyD88/NF-κB signaling pathway, which suggests that BMSCs-derived exosomes are expected to become a new therapeutic strategy for SCI.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Chiaki Yamada ◽  
Aiko Maeda ◽  
Katsuyuki Matsushita ◽  
Shoko Nakayama ◽  
Kazuhiro Shirozu ◽  
...  

Abstract Background Patients with spinal cord injury (SCI) frequently complain of intractable pain that is resistant to conservative treatments. Here, we report the successful application of 1-kHz high-frequency spinal cord stimulation (SCS) in a patient with refractory neuropathic pain secondary to SCI. Case presentation A 69-year-old male diagnosed with SCI (C4 American Spinal Injury Association Impairment Scale A) presented with severe at-level bilateral upper extremity neuropathic pain. Temporary improvement in his symptoms with a nerve block implied peripheral component involvement. The patient received SCS, and though the tip of the leads could not reach the cervical vertebrae, a 1-kHz frequency stimulus relieved the intractable pain. Conclusions SCI-related symptoms may include peripheral components; SCS may have a considerable effect on intractable pain. Even when the SCS electrode lead cannot be positioned in the target area, 1-kHz high-frequency SCS may still produce positive effects.


2021 ◽  
pp. 197140092110268
Author(s):  
Seyedeh Niloufar Rafiei Alavi ◽  
Arian Madani Neishaboori ◽  
Mahmoud Yousefifard

Background As there is no consensus over the efficacy of extracorporeal shockwave therapy in the management of spinal cord injury complications, the current meta-analysis aims to investigate preclinical evidence on the matter. Methods The search strategy was developed based on keywords related to ‘spinal cord injury’ and ‘extracorporeal shockwave therapy’. A primary search was conducted in Medline, Embase, Scopus and Web of Science until the end of 2020. Studies which administered extracorporeal shockwave therapy on spinal cord injury animal models and evaluated motor function and/or histological findings were included. The standardised mean difference with a 95% confidence interval (CI) were calculated. Results Seven articles were included. Locomotion was significantly improved in the extracorporeal shockwave therapy treated group (standardised mean difference 1.68, 95% CI 1.05–2.31, P=0.032). It seems that the efficacy of extracorporeal shockwave therapy with an energy flux density of 0.1 mJ/mm2 is higher than 0.04 mJ/mm2 ( P=0.044). Shockwave therapy was found to increase axonal sprouting (standardised mean difference 1.31, 95% CI 0.65, 1.96), vascular endothelial growth factor tissue levels (standardised mean difference 1.36, 95% CI 0.54, 2.18) and cell survival (standardised mean difference 2.49, 95% CI 0.93, 4.04). It also significantly prevents axonal degeneration (standardised mean difference 2.25, 95% CI 1.47, 3.02). Conclusion Extracorporeal shockwave therapy significantly improves locomotor recovery in spinal cord injury animal models through neural tissue regeneration. Nonetheless, in spite of the promising results and clinical application of extracorporeal shockwave therapy in various conditions, current evidence implies that designing clinical trials on extracorporeal shockwave therapy in the management of spinal cord injury may not be soon. Hence, further preclinical studies with the effort to reach the safest and the most efficient treatment protocol are needed.


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