Electro-acupuncture and its combination with adult stem cell transplantation for spinal cord injury treatment: A summary of current laboratory findings and a review of literature

Advances in acupuncture treatment for tinnitus

Tinnitus is the abnormal perception of sound in the absence of a corresponding external acoustic stimulus, which seriously affects the patients' quality of life, physical and mental health, and the safety of life. There is almost no effective cure for tinnitus, primarily due to its complicated etiopathogenesis and unclear mechanisms. As a major and ancient physical therapy in Traditional Chinese Medicine, acupuncture has been widely used in tinnitus because of its simple operation, rapid effect, and low cost. This paper reviews the relevant literature on the treatment of different kinds of tinnitus by acupuncture, and summarizes the therapeutic efficacy and mechanism of acupuncture on tinnitus, which is expected to provide new ideas and research directions for the study of tinnitus treatment by acupuncture. Tinnitus is the abnormal perception of sound in the absence of a corresponding external acoustic stimulus, which seriously affects the patients' quality of life, physical and mental health, and the safety of life. There is almost no effective cure for tinnitus, primarily due to its complicated etiopathogenesis and unclear mechanisms. As a major and ancient physical therapy in Traditional Chinese Medicine, acupuncture has been widely used in tinnitus because of its simple operation, rapid effect, and low cost. This paper reviews the relevant literature on the treatment of different kinds of tinnitus by acupuncture, and summarizes the therapeutic efficacy and mechanism of acupuncture on tinnitus, which is expected to provide new ideas and research directions for the study of tinnitus treatment by acupuncture.

[Experimental study of M2 microglia transplantation promoting spinal cord injury repair in mice]

Objective

To investigate the effect of M2 microglia (M2-MG) transplantation on spinal cord injury (SCI) repair in mice.

Methods

Primary MG were obtained from the cerebral cortex of 15 C57BL/6 mice born 2-3 days old by pancreatic enzyme digestion and identified by immunofluorescence staining of Iba1. Then the primary MG were co-cultured with interleukin 4 for 48 hours (experimental group) to induce into M2 phenotype and identified by immunofluorescence staining of Arginase 1 (Arg-1) and Iba1. The normal MG were harvested as control (control group). The dorsal root ganglion (DRG) of 5 C57BL/6 mice born 1 week old were co-cultured with M2-MG for 5 days to observe the axon length, the DRG alone was used as control. Forty-two 6-week-old female C57BL/6 mice were randomly divided into sham group ( n=6), SCI group ( n=18), and SCI+M2-MG group ( n=18). In sham group, only the laminae of T 10 level were removed; SCI group and SCI+M2-MG group underwent SCI modeling, and SCI+M2-MG group was simultaneously injected with M2-MG. The survival of mice in each group was observed after operation. At immediate (0), 3, 7, 14, 21, and 28 days after operation, the motor function of mice was evaluated by Basso Mouse Scale (BMS) score, and the gait was evaluated by footprint experiment at 28 days. The spinal cord tissue was taken after operation for immunofluorescence staining, in which glial fibrillary acidic protein (GFAP) staining at 7, 14, and 28 days was used to observe the injured area of the spinal cord, neuronal nuclei antigen staining at 28 days was used to observe the survival of neurons, and GFAP/C3 double staining at 7 and 14 days was used to observe the changes in the number of A1 astrocytes.

Results

The purity of MG in vitro reached 90%, and the most of the cells were polarized into M2 phenotype identified by Arg-1 immunofluorescence staining. M2-MG promoted the axon growth when co-cultured with DRGs in vitro ( P<0.05). All groups of mice survived until the experiment was completed. The hind limb motor function of SCI group and SCI+M2-MG group gradually recovered over time. Among them, the SCI+M2-MG group had significantly higher BMS scores than the SCI group at 21 and 28 days ( P<0.05), and the dragging gait significantly improved at 28 days, but it did not reach the level of the sham group. Immunofluorescence staining showed that compared with the SCI group, the SCI+M2-MG group had a smaller injury area at 7, 14, and 28 days, an increase in neuronal survival at 28 days, and a decrease in the number of A1 astrocytes at 7 and 14 days, with significant differences ( P<0.05).

Conclusion

M2-MG transplantation improves the motor function of the hind limbs of SCI mice by promoting neuron survival and axon regeneration. This neuroprotective effect is related to the inhibition of A1 astrocytes polarization.

Application and challenges of olfactory ensheathing cells in clinical trials of spinal cord injury

Spinal cord injury (SCI) can lead to severe motor, sensory and autonomic nervous dysfunction, cause serious psychosomatic injury to patients. There is no effective treatment for SCI at present. In recent years, exciting evidence has been obtained in the application of cell-based therapy in basic research. These studies have revealed the fact that cells transplanted into the host can exert the pharmacological properties of treating and repairing SCI. Olfactory ensheathing cells (OECs) are a kind of special glial cells. The application value of OECs in the study of SCI lies in their unique biological characteristics, that is, they can survive and renew for life, give full play to neuroprotection, immune regulation, promoting axonal regeneration and myelination formation. The function of producing secretory group and improving microenvironment. This provides an irreplaceable treatment strategy for the repair of SCI. At present, some researchers have explored the possibility of treatment of OECs in clinical trials of SCI. Although OECs transplantation shows excellent safety and effectiveness in animal models, there is still lack of sufficient evidence to prove the effectiveness of their clinical application in clinical trials. There has been an obvious stagnation in the transformation of OECs transplantation into routine clinical practice, and clinical trials of cell therapy in this field are still facing major challenges and many problems that need to be solved. Therefore, this paper summarized and analyzed the clinical trials of OECs transplantation in the treatment of SCI, and discussed the problems and challenges of OECs transplantation in clinical trials.

Electroacupuncture promotes the repair of the damaged spinal cord in mice by mediating neurocan-perineuronal net

AIMS

This study aimed to investigate the effect of perineuronal net (PNN) and neurocan (NCAN) on spinal inhibitory parvalbumin interneuron (PV-IN), and the mechanism of electroacupuncture (EA) in promoting spinal cord injury (SCI) repair through neurocan in PNN.

METHODS

A mouse model of SCI was established. Sham-operated mice or SCI model mice were treated with chondroitin sulfate ABC (ChABC) enzyme or control vehicle for 2 weeks (i.e., sham+veh group, sham+ChABC group, SCI+veh group, and SCI+ChABC group, respectively), and then spinal cord tissues were taken from the T10 lesion epicenter for RNA sequencing (RNA-seq). MSigDB Hallmark and C5 databases for functional analysis, analysis strategies such as differential expression gene analysis (DEG), Kyoto Encyclopedia of Genes and Genomes (KEGG), gene set enrichment analysis (GSEA), and protein-protein interaction (PPI). According to the results of RNA-seq analysis, the expression of NCAN was knocked down or overexpressed by virus intervention, or/and EA intervention. Polymerase chain reaction (PCR), immunofluorescence, western blot, electrophysiological, and behavioral tests were performed.

RESULTS

After the successful establishment of SCI model, the motor dysfunction of lower limbs, and the expression of PNN core glycan protein at the epicenter of SCI were reduced. RNA-seq and PCR showed that PNN core proteoglycans except NCAN showed the same expression trend in normal and injured spinal cord treated with ChABC. KEGG and GSEA showed that PNN is mainly associated with inhibitory GABA neuronal function in injured spinal cord tissue, and PPI showed that NCAN in PNN can be associated with inhibitory neuronal function through parvalbumin (PV). Calcium imaging showed that local parvalbumin interneuron (PV-IN) activity decreased after PNN destruction, whether due to ChABC treatment or surgical bruising of the spinal cord. Overexpression of neurocan in injured spinal cord can enhance local PV-IN activity. PCR and western blot suggested that overexpression or knockdown of neurocan could up-regulate or down-regulate the expression of GAD. At the same time, the activity of PV-IN in the primary motor cortex (M1) and the primary sensory cortex of lower (S1HL) extremity changed synchronously. In addition, overexpression of neurocan improved the electrical activity of the lower limb and promoted functional repair of the paralyzed hind limb. EA intervention reversed the down-regulation of neurocan, enhanced the expression of PNN in the lesioned area, M1 and S1HL.

CONCLUSION

Neurocan in PNN can regulate the activity of PV-IN, and EA can promote functional recovery of mice with SCI by upregulating neurocan expression in PNN.

Electrical stimulation affects the differentiation of transplanted regionally specific human spinal neural progenitor cells (sNPCs) after chronic spinal cord injury

BACKGROUND

There are currently no effective clinical therapies to ameliorate the loss of function that occurs after spinal cord injury. Electrical stimulation of the rat spinal cord through the rat tail has previously been described by our laboratory. We propose combinatorial treatment with human induced pluripotent stem cell-derived spinal neural progenitor cells (sNPCs) along with tail nerve electrical stimulation (TANES). The purpose of this study was to examine the influence of TANES on the differentiation of sNPCs with the hypothesis that the addition of TANES would affect incorporation of sNPCs into the injured spinal cord, which is our ultimate goal.

METHODS

Chronically injured athymic nude rats were allocated to one of three treatment groups: injury only, sNPC only, or sNPC + TANES. Rats were sacrificed at 16 weeks post-transplantation, and tissue was processed and analyzed utilizing standard histological and tissue clearing techniques. Functional testing was performed. All quantitative data were presented as mean ± standard error of the mean. Statistics were conducted using GraphPad Prism.

RESULTS

We found that sNPCs were multi-potent and retained the ability to differentiate into mainly neurons or oligodendrocytes after this transplantation paradigm. The addition of TANES resulted in more transplanted cells differentiating into oligodendrocytes compared with no TANES treatment, and more myelin was found. TANES not only promoted significantly higher numbers of sNPCs migrating away from the site of injection but also influenced long-distance axonal/dendritic projections especially in the rostral direction. Further, we observed localization of synaptophysin on SC121-positive cells, suggesting integration with host or surrounding neurons, and this finding was enhanced when TANES was applied. Also, rats that were transplanted with sNPCs in combination with TANES resulted in an increase in serotonergic fibers in the lumbar region. This suggests that TANES contributes to integration of sNPCs, as well as activity-dependent oligodendrocyte and myelin remodeling of the chronically injured spinal cord.

CONCLUSIONS

Together, the data suggest that the added electrical stimulation promoted cellular integration and influenced the fate of human induced pluripotent stem cell-derived sNPCs transplanted into the injured spinal cord.

Electroacupuncture for acute transverse myelitis following viral infection: A case report

BACKGROUND

Electroacupuncture (EA) has a positive effect on neurological repair and functional recovery following spinal cord disease. However, evidence of its effectiveness in acute transverse myelitis (ATM) cases is limited.

PATIENT PRESENTATION

A 48-year-old woman experienced headache and fever for 5 days, followed by a sudden onset of back pain, lower limb paralysis, and urinary and bowel dysfunction. The patient received intravenous medications. However, she did not experience improvement in clinical symptoms. She subsequently underwent acupuncture treatment. She regained walking ability and experienced improved bladder function and bowel control after 36 sessions of EA treatment.

METHODS

CARE guidelines informed the case study report. The MRC and ICIQ-UI-SF scores were used to verify changes in lower-extremity muscle strength and urination after EA treatment. Qualitative information was collected using feedback tables.

CONCLUSION

Pharmacological treatment for ATM lacks clear advantages because of its complex pathophysiological mechanisms. Hence, EA could be recommended as a promising treatment modality for ATM.

Potential therapeutic effect of olfactory ensheathing cells in neurological diseases: neurodegenerative diseases and peripheral nerve injuries

Neurological diseases are destructive, mainly characterized by the failure of endogenous repair, the inability to recover tissue damage, resulting in the increasing loss of cognitive and physical function. Although some clinical drugs can alleviate the progression of these diseases, but they lack therapeutic effect in repairing tissue injury and rebuilding neurological function. More and more studies have shown that cell therapy has made good achievements in the application of nerve injury. Olfactory ensheathing cells (OECs) are a special type of glial cells, which have been proved to play an important role as an alternative therapy for neurological diseases, opening up a new way for the treatment of neurological problems. The functional mechanisms of OECs in the treatment of neurological diseases include neuroprotection, immune regulation, axon regeneration, improvement of nerve injury microenvironment and myelin regeneration, which also include secreted bioactive factors. Therefore, it is of great significance to better understand the mechanism of OECs promoting functional improvement, and to recognize the implementation of these treatments and the effective simulation of nerve injury disorders. In this review, we discuss the function of OECs and their application value in the treatment of neurological diseases, and position OECs as a potential candidate strategy for the treatment of nervous system diseases.

Acupuncture acupoints of spine and lower limb for pediatric backbend-induced thoracic spinal cord injury: Four case reports and literature review

BACKGROUND

Backbend-induced pediatric thoracic spinal cord injury without radiologic abnormality (BBPT-SCIWORA) in children is rare in clinical practice and leads to lower limb motor dysfunction. There are few clinical studies on BBPT-SCIWORA and even fewer on treatments for BBPT-SCIWORA-induced lower limb motor dysfunction.

OBJECTIVE

To explore the therapeutic effect of acupuncture at bilateral spine acupoints combined with lower limb acupoints in BBPT-SCIWORA.

CASE PRESENTATION

This study reported four cases of BBPT-SCIWORA after dancing, two of which received a unique medium-frequency electroacupuncture treatment. They were all females aged between 5 and 12 years old. They were diagnosed with BBPT-SCIWORA by magnetic resonance imaging (MRI), transferred to the rehabilitation department for lower limb dysfunction, and received rehabilitation treatments and acupuncture. Cases 1 and 2 received acupuncture treatment for lower limb acupoints, while Cases 3 and 4 received acupuncture treatment at the bilateral spine acupoints beside the lesion and lower limb acupoints. Cases 3 and 4 achieved better American spinal injury association (AIS) grades and lower extremity motor scores (LEMS) than Cases 1 and 2 after treatment.

CONCLUSION

Acupuncture treatment of beside bilateral spine acupoints plus lower limb acupoints therapy might facilitate early lower limb motor function recovery in children with BBPT-SCIWORA.

Activating Endogenous Neurogenesis for Spinal Cord Injury Repair: Recent Advances and Future Prospects

After spinal cord injury (SCI), endogenous neural stem cells are activated and migrate to the injury site where they differentiate into astrocytes, but they rarely differentiate into neurons. It is difficult for brain-derived information to be transmitted through the injury site after SCI because of the lack of neurons that can relay neural information through the injury site, and the functional recovery of adult mammals is difficult to achieve. The development of bioactive materials, tissue engineering, stem cell therapy, and physiotherapy has provided new strategies for the treatment of SCI and shown broad application prospects, such as promoting endogenous neurogenesis after SCI. In this review, we focus on novel approaches including tissue engineering, stem cell technology, and physiotherapy to promote endogenous neurogenesis and their therapeutic effects on SCI. Moreover, we explore the mechanisms and challenges of endogenous neurogenesis for the repair of SCI.

Tail nerve electrical stimulation promoted the efficiency of transplanted spinal cord-like tissue as a neuronal relay to repair the motor function of rats with transected spinal cord injury

Following transected spinal cord injury (SCI), there is a critical need to restore nerve conduction at the injury site and activate the silent neural circuits caudal to the injury to promote the recovery of voluntary movement. In this study, we generated a rat model of SCI, constructed neural stem cell (NSC)-derived spinal cord-like tissue (SCLT), and evaluated its ability to replace injured spinal cord and repair nerve conduction in the spinal cord as a neuronal relay. The lumbosacral spinal cord was further activated with tail nerve electrical stimulation (TNES) as a synergistic electrical stimulation to better receive the neural information transmitted by the SCLT. Next, we investigated the neuromodulatory mechanism underlying the action of TNES and its synergism with SCLT in SCI repair. TNES promoted the regeneration and remyelination of axons and increased the proportion of glutamatergic neurons in SCLT to transmit brain-derived neural information more efficiently to the caudal spinal cord. TNES also increased the innervation of motor neurons to hindlimb muscle and improved the microenvironment of muscle tissue, resulting in effective prevention of hindlimb muscle atrophy and enhanced muscle mitochondrial energy metabolism. Tracing of the neural circuits of the sciatic nerve and tail nerve identified the mechanisms responsible for the synergistic effects of SCLT transplantation and TNES in activating central pattern generator (CPG) neural circuits and promoting voluntary motor function recovery in rats. The combination of SCLT and TNES is expected to provide a new breakthrough for patients with SCI to restore voluntary movement and control their muscles.

Thoracic Jia-Ji electro-acupuncture mitigates low skeletal muscle atrophy and improves motor function recovery following thoracic spinal cord injury in rats

OBJECTIVES

The goal of this study was to determine whether electro-acupuncture (EA) stimulation might protect the motor endplate, minimize muscle atrophy in the hind limbs, and enhance functional recovery of rats with spinal cord injury (SCI).

METHODS

Sprague-Dawley adult female rats (n = 30) were randomly assigned into Sham, SCI, and EA + SCI groups (n = 10 each). Rats in the Sham and SCI groups were bound in prone position only for 30 min, and rats in the EA + SCI group were treated with electro-acupuncture. The EA was conducted from the first day after surgery, lasted for 30 mins, once every day for 28 consecutive days.

RESULTS

EA significantly prevented motor endplate degeneration, improved electrophysiological function, and ameliorated hindlimb muscle atrophy after SCI. Meanwhile, EA upregulated Tuj-1 expression, downregulated GFAP expression, and reduced glial scar formation. Additionally, after 4 weeks of EA treatment, the serum of SCI rats exhibited a reduced inflammatory response.

CONCLUSION

These findings suggest that EA can preserve the motor endplate and reduce muscular atrophy. In addition, EA has been shown to improve the function of upper and lower neurons, reduce glial scar formation, suppress systemic inflammation, and improve axon regeneration.

Multimodal Repair of Spinal Cord Injury With Mesenchymal Stem Cells

Spinal cord injury (SCI) is a result of a devastating injury to the central nervous system. Currently, there is no effective treatment available for these patients. The possible use of mesenchymal stem cell (MSC)-based treatment for SCI has been the focus of extensive investigations and is increasingly moving from the bench to bedside. Both experimental observations and clinical studies have shown the safety and efficacy of MSCs in managing SCI. However, the exact mechanism by which MSCs contribute to the repair of the injured spinal cord remains to be elucidated. In this review, we aim to summarize current research findings about the role of MSCs in improving complex pathology after SCI. MSCs exert a multimodal repair mechanism targeting multiple events in the secondary injury cascade. Our recent results showing the perineurium-like differentiation of surviving MSCs in the injured spinal cord may further the understanding of the fate of transplanted MSCs. These findings provide fundamental support for the clinical use of MSCs in SCI patients. Under experimental conditions, combining novel physical, chemical, and biological approaches led to significant improvements in the therapeutic efficacy of MSCs. These findings hold promise for the future of cell-based clinical treatment of SCI.

Transcription Profiling of a Revealed the Potential Molecular Mechanism of Governor Vessel Electroacupuncture for Spinal Cord Injury in Rats

OBJECTIVE

This study aimed to identify differentially expressed genes (DEGs) by transcriptome analysis to elucidate a potential mechanism by which governor vessel electroacupuncture (GV-EA) promotes neuronal survival, axonal regeneration, and functional recovery after complete transection spinal cord injury (SCI).

METHODS

Sham, control, or GV-EA group adult female Sprague Dawley rats underwent a complete transection SCI protocol. SCI area RNA-seq investigated the DEGs of coding and noncoding RNAs 7 days post-SCI. Gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) enrichment analyses were used to classify DEGs functions, to explain a possible molecular mechanism. Immunofluorescence and BBB (Basso, Beattie, and Bresnahan) score were used to verify a GV-EA treatment effect following SCI.

RESULTS

GV-EA treatment could regulate the expression of 173 mRNA, 260 lncRNA, and 153 circRNA genes among these DEGs resulted by SCI. GO enrichment analysis showed that the DEGs were most enriched in membrane, actin binding, and regulation of Toll-like receptor signaling pathway. KEGG pathway analysis showed enriched pathways (e.g. , Toll-like receptors, MAPK, Hippo signaling). According to the ceRNA network, miR-144-3p played a regulatory role by interacting with lncRNA and circRNA. GV-EA also promoted the injured spinal cord neuron survival, axonal regeneration, and functional improvement of hind limb locomotion.

CONCLUSION

Results of our RNA-seq suggest that post-SCI GV-EA may regulate characteristic changes in transcriptome gene expression, potential critical genes, and signaling pathways, providing clear directions for further investigation into the mechanism of GV-EA in subacute SCI treatment. Moreover, we found that GV-EA promotes neuronal survival, nerve fiber extension, and motor function recovery in subacute SCI.

Effects of Zinc, Magnesium, and Iron Ions on Bone Tissue Engineering

Large-sized bone defects are a great challenge in clinics and considerably impair the quality of patients' daily life. Tissue engineering strategies using cells, scaffolds, and bioactive molecules to regulate the microenvironment in bone regeneration is a promising approach. Zinc, magnesium, and iron ions are natural elements in bone tissue and participate in many physiological processes of bone metabolism and therefore have great potential for bone tissue engineering and regeneration. In this review, we performed a systematic analysis on the effects of zinc, magnesium, and iron ions in bone tissue engineering. We focus on the role of these ions in properties of scaffolds (mechanical strength, degradation, osteogenesis, antibacterial properties, etc.). We hope that our summary of the current research achievements and our notifications of potential strategies to improve the effects of zinc, magnesium, and iron ions in scaffolds for bone repair and regeneration will find new inspiration and breakthroughs to inspire future research.

Effects of Electroactive materials on nerve cell behaviors and applications in peripheral nerve repair

Peripheral nerve damage can lead to loss of function or even complete disability, which bring about a huge burden on both the patient and society. Regulating nerve cell behavior and...