OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Jiaji" (EX-B 2) points on the proliferation and differentiation of oligodendrocyte precursor cells in rats with acute incomplete spinal cord injury, and to explore the mechanism of EA on improving motor function of spinal cord injury. METHODS: A total of 72 male SPF SD rats were randomly divided into a sham operation group, a model group, an EA group and a medication group, 18 rats in each group. Each group was further divided into 1-day subgroup, 7-day subgroup and 14-day subgroup, 6 rats in each subgroup. The T acute incomplete spinal cord injury model was established by modified Allen's method in the model group, EA group and medication group. The rats in each group received intraperitoneal injection of 5-bromodeoxyuridine (BrdU, 50 mg/kg), once a day, and each subgroup received continuous injection for 1, 7, 14 times for cell proliferation labeling. The rats in the EA group were treated with EA at "Jiaji" (EX-B 2) points 3-4 mm next the spinous process of the upper and lower segments of the injured spinal cord (T, T) with a frequency of 2 Hz/100 Hz and intensity of 1-2 mA. The muscle twitch at the treatment site was taken as the degree. The treatment was given 20 min each time, once a day. In the medication group, monosialogangliosides (GM1) was injected intraperitoneally (10 mg/kg), once a day. The subgroups of EA group and medication group were treated for 1, 7, 14 times. The score of Basso Beattie Bresnahan (BBB) was used to evaluate the motor function of hind limbs. The co-expression of BrdU/NG2 positive cells was detected by immunofluorescence, and the expression of Olig2 and Sox10 was detected by Western blot. RESULTS: Compared with the sham operation group, the BBB score was decreased 1 day, 7 days and 14 days after operation in the model group (<0.05), the expression of Olig2 and Sox10 was increased (<0.05), and the co-expression of BrdU/NG2 positive cells was increased 7 days and 14 days after operation (<0.05). Seven days and 14 days after operation, the BBB score in the EA group and medication group was higher than that in the model group (<0.05), and the co-expression of BrdU/NG2 in the medication group was higher than that in the model group (<0.05). Fourteen days after operation, the co-expression of BrdU/NG2 in the EA group was higher than that in the model group (<0.05); 1 day, 7 days and 14 days after operation, the expression of Olig2 and Sox10 in the EA group and medication group was higher than that in the model group (<0.05). Compared with the medication group, the co-expression of BrdU/NG2 positive cells in the EA group 14 days after operation was decreased (<0.05); 1 day, 7 days and 14 days after operation, the expression of Olig2 and Sox10 in the EA group was decreased (<0.05). CONCLUSION EA at "Jiaji" (EX-B 2) points could promote the expression of Olig2 and Sox10 after spinal cord injury, which has similar effects with GM1. It could promote the proliferation and differentiation of oligodendrocyte precursor cells into oligodendrocytes, so as to promote the recovery of motor function of rats.
Acupuncture Points ; Animals ; Cell Differentiation ; Cell Proliferation ; Electroacupuncture ; Humans ; Male ; Oligodendrocyte Precursor Cells ; cytology ; Oligodendrocyte Transcription Factor 2 ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; SOXE Transcription Factors ; metabolism ; Spinal Cord ; Spinal Cord Injuries ; therapy

Spinal cord injury (SCI), which is much in the public eye, is still a refractory disease compromising the well-being of both patients and society. In spite of there being many methods dealing with the lesion, there is still a deficiency in comprehensive strategies covering all facets of this damage. Further, we should also mention the structure called the corticospinal tract (CST) which plays a crucial role in the motor responses of organisms, and it will be the focal point of our attention. In this review, we discuss a variety of strategies targeting different dimensions following SCI and some treatments that are especially efficacious to the CST are emphasized. Over recent decades, researchers have developed many effective tactics involving five approaches: (1) tackle more extensive regions; (2) provide a regenerative microenvironment; (3) provide a glial microenvironment; (4) transplantation; and (5) other auxiliary methods, for instance, rehabilitation training and electrical stimulation. We review the basic knowledge on this disease and correlative treatments. In addition, some well-formulated perspectives and hypotheses have been delineated. We emphasize that such a multifaceted problem needs combinatorial approaches, and we analyze some discrepancies in past studies. Finally, for the future, we present numerous brand-new latent tactics which have great promise for curbing SCI.
Animals ; Astrocytes/cytology* ; Axons/physiology* ; Cell Transplantation ; Disease Models, Animal ; Electric Stimulation ; Humans ; Microglia/cytology* ; Motor Neurons/cytology* ; Nerve Regeneration ; Neuroglia/cytology* ; Neuronal Plasticity ; Neurons/cytology* ; Oligodendroglia/cytology* ; Pyramidal Tracts/pathology* ; Recovery of Function ; Regenerative Medicine/methods* ; Spinal Cord Injuries/therapy*

OBJECTIVETo study whether lithium agent produces neuroprotective effect by inhibiting the nerve cell apoptosis of rats after spinal cord injury.

METHODSForty-two male SD rats weighing 200 to 250 g were randomly divided into 3 groups: blank control group(=6) without surgery, normal saline(NS) group(=18) with intraperitoneal injection of NS (40 mg/kg); and Lithium chloride (Licl) group (=18) with intraperitoneal injection of Licl (40 mg/kg). After Allen method modeling, Licl group started intraperitoneal injection of Licl solution (40 mg·kg⁻¹·d⁻¹) within 15 min after operation to the second week. NS group, during the same interval, was injected with a same amount of NS. Postoperative 3, 7, 14 d, BBB scores in each group were measured;the expression of Bcl-2 and Bax protein were observed by immunohistochemisty staining;TUNEL staining was used to observe the nerve cell apoptosis.

RESULTSThe BBB scores in blank control group were 21. Postoperative 7, 14 d, BBB scores of Licl group were higher than that of NS group(<0.05). As for the Bcl-2 protein expression, black control group has a level of 0.081±0.003;7 d and 14 d postoperatively, the level in Licl group was 0.151±0.003, 0.163±0.003 and in NS group, 0.143±0.003, 0.154±0.002, respectively. Licl group showed significantly increased Bcl-2 protein expression(<0.05). As for the Bax protein expression, black control group showed a level of 0.071±0.003; 7 d and 14 d postoperatively, the level in Licl group was 0.121±0.002, 0.106±0.002 and in NS group was 0.126±0.001, 0.120±0.002, respectively. The Bax protein expression is significantly inhibited in the Licl group(<0.05). In nerve cell apoptosis by TUNEL staining, the positive cells were fewer in the black control group with apoptosis index (AI) of 1.98±0.19;while 7d and 14d postoperatively, the AI of Licl group was 13.12±0.69, 4.29±1.00 and of NS group, 18.26±0.87, 5.48±0.70, respectively. Licl group showed significant inhibition of the cell apoptosis(<0.05).

CONCLUSIONSLicl can promote the Bcl-2 protein expression and inhibit the Bax proteins expression in nerve cells of rat after SCI, thereby playing a role in the inhibition of nerve cell apoptosis. This may be one of the mechanisms that Licl can promote the recovery of motor function of rats after SCI.

Animals ; Apoptosis ; Lithium ; pharmacology ; Male ; Neurons ; cytology ; drug effects ; Neuroprotective Agents ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Spinal Cord Injuries ; drug therapy ; bcl-2-Associated X Protein ; metabolism

Mounting evidence supports an important role of chemokines, produced by spinal cord astrocytes, in promoting central sensitization and chronic pain. In particular, CCL2 (C-C motif chemokine ligand 2) has been shown to enhance N-methyl-D-aspartate (NMDA)-induced currents in spinal outer lamina II (IIo) neurons. However, the exact molecular, synaptic, and cellular mechanisms by which CCL2 modulates central sensitization are still unclear. We found that spinal injection of the CCR2 antagonist RS504393 attenuated CCL2- and inflammation-induced hyperalgesia. Single-cell RT-PCR revealed CCR2 expression in excitatory vesicular glutamate transporter subtype 2-positive (VGLUT2) neurons. CCL2 increased NMDA-induced currents in CCR2/VGLUT2 neurons in lamina IIo; it also enhanced the synaptic NMDA currents evoked by dorsal root stimulation; and furthermore, it increased the total and synaptic NMDA currents in somatostatin-expressing excitatory neurons. Finally, intrathecal RS504393 reversed the long-term potentiation evoked in the spinal cord by C-fiber stimulation. Our findings suggest that CCL2 directly modulates synaptic plasticity in CCR2-expressing excitatory neurons in spinal lamina IIo, and this underlies the generation of central sensitization in pathological pain.
Animals ; Benzoxazines ; pharmacology ; therapeutic use ; Chemokine CCL2 ; antagonists & inhibitors ; genetics ; metabolism ; pharmacology ; Excitatory Amino Acid Agents ; pharmacology ; Excitatory Amino Acid Agonists ; pharmacology ; Female ; Freund's Adjuvant ; toxicity ; Hyperalgesia ; chemically induced ; metabolism ; prevention & control ; Long-Term Potentiation ; drug effects ; physiology ; Luminescent Proteins ; genetics ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Transgenic ; Myelitis ; chemically induced ; drug therapy ; metabolism ; Neurons ; drug effects ; Pain Management ; Somatostatin ; genetics ; metabolism ; Spinal Cord ; cytology ; Spiro Compounds ; pharmacology ; therapeutic use ; Vesicular Glutamate Transport Protein 2 ; genetics ; metabolism ; Vesicular Inhibitory Amino Acid Transport Proteins ; genetics ; metabolism

To investigate the role of spinal interleukin-6-Janus kinase 2 (IL-6-JAK2) signaling transduction pathway in regulating astrocytes activation during the maintenance of bone cancer pain (BCP).
 Methods: NCTC 2472 fibrosarcoma cells were injected into the femur marrow cavity in C3H/HeNCrlVr male mice to establish BCP model and they were replaced by the equal volume of α-MEM in the sham model. The paw withdrawal latency (PWL) was measured after inoculation of tumor cells. The lumbar enlargement of spinal cord (L3-L5) was isolated, and Real-time RT-PCR and Western blot were used to detect the expression of spinal glial fibrillary acidic protein (GFAP) and JAK2 mRNA and protein, respectively. The expression level of spinal GFAP mRNA indirectly reflect astrocytes activation level. Pain behaviors and spinal cord GFAP mRNA and protein expression were observed at the given time points after intrathecal administration of JAK2 antagonist AG-490.
 Results: The PWL at 10, 14, 21 d after operation in BCP model group were significantly shorter than that in the sham group (P<0.05); the spinal GFAP and JAK2 mRNA and protein levels were higher in the BCP model group in comparison to mice in the sham group (P<0.05); intrathecal injection of JAK2 agonist AG-490 (30 or 90 nmol) significantly alleviated PWL, and downregulated the expression of spinal GFAP mRNA and protein (P<0.05).
 Conclusion: The IL-6-JAK2 signaling pathway plays an important role in maintaining the BCP by regulating the expression of GFAP in the spinal cord. Intrathecal injection of AG-490 can reduce the BCP, and inhibit the activation of IL-6-JAK2 signaling pathway, which may be one of the mechanisms for spinal astrocyte activation.
Animals ; Astrocytes ; pathology ; Bone Neoplasms ; complications ; Hyperalgesia ; drug therapy ; etiology ; Injections, Spinal ; Male ; Mice ; Mice, Inbred C3H ; Rats, Sprague-Dawley ; Spinal Cord ; cytology ; pathology ; Tyrphostins ; administration & dosage

OBJECTIVETo investigate the rebound depolarization of substantia gelatinosa (SG) neurons in rat spinal dorsal horn and explore its modulatory mechanisms to provide better insights into rebound depolarization-related diseases.

METHODSParasagittal slices of the spinal cord were prepared from 3- to 5-week-old Sprague-Dawley rats. The electrophysiologic characteristics and responses to hyperpolarization stimulation were recorded using whole-cell patch-clamp technique. The effects of hyperpolarization-activated cyclic nucleotide gated cation (HCN) channel blockers and T-type calcium channel blockers on rebound depolarization of the neurons were studied.

RESULTSA total of 63 SG neurons were recorded. Among them, 23 neurons showed no rebound depolarization, 19 neurons showed rebound depolarization without spikes, and 21 neurons showed rebound depolarization with spikes. The action potential thresholds of the neurons without rebound depolarization were significantly higher than those of the neurons with rebound depolarization and spikes (-28.7∓1.6 mV vs -36.0∓2.0 mV, P<0.05). The two HCN channel blockers CsCl and ZD7288 significantly delayed the latency of rebound depolarization with spike from 45.9∓11.6 ms to 121.6∓51.3 ms (P<0.05) and from 36.2∓10.3 ms to 73.6∓13.6 ms (P<0.05), respectively. ZD7288 also significantly prolonged the latency of rebound depolarization without spike from 71.9∓35.1 ms to 267.0∓68.8 ms (P<0.05). The T-type calcium channel blockers NiCl2 and mibefradil strongly decreased the amplitude of rebound depolarization with spike from 19.9∓6.3 mV to 9.5∓4.5 mV (P<0.05) and from 26.1∓9.4 mV to 15.5∓5.0 mV (P<0.05), respectively. Mibefradil also significantly decreased the amplitude of rebound depolarization without spike from 14.3∓3.0 mV to 7.9∓2.0 mV (P<0.05).

CONCLUSIONNearly two-thirds of the SG neurons have rebound depolarizations modulated by HCN channel and T-type calcium channel.

Action Potentials ; Animals ; Calcium Channel Blockers ; pharmacology ; Calcium Channels, T-Type ; Cell Polarity ; Cesium ; pharmacology ; Chlorides ; pharmacology ; Cyclic Nucleotide-Gated Cation Channels ; antagonists & inhibitors ; Neurons ; cytology ; Patch-Clamp Techniques ; Pyrimidines ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Spinal Cord Dorsal Horn ; cytology ; Substantia Gelatinosa ; cytology

Chronic spinal cord compression is the common clinical prognosis with various outcomes, but the affecting factors and mechanisms still remain unexplored. The structure and function of neurovascular unit manifest great significance in the central nervous system diseases. This paper discusses matrix metalloproteinase (MMP) impact on the stability of the neural vascular unit, by directly decomposing extracellular matrix, inducing the glial cell migration, activating angiogenesis, regulating function of blood spinal cord barrier, and put forward the MMP may be the key points in regulation of spinal cord neurovascular unit structure and function change to affect the outcome of chronic oppressive cervical spinal cord.
Cell Movement ; Humans ; Matrix Metalloproteinases ; physiology ; Nerve Compression Syndromes ; diagnosis ; enzymology ; Neurons ; cytology ; Prognosis ; Spinal Cord Injuries ; diagnosis ; enzymology

OBJECTIVETo observe the effects of mecobalamin on the expression of apoptosis-related proteins, Bax and Bcl-2, in neurons after peripheral nerve injury, and to explore the role of neuron apoptosis in peripheral nerve regeneration after injury.

METHODSThirty healthy adult male wistar rats were randomly divided into sham-operation group, model group, and mecobalamin group, with 10 rats in each group. A rat model of left sciatic nerve semi-injury was established using forceps. Rats in the mecobalamin group were fed mecobalamin, while rats in the sham-operation group and model group were given the same dose of normal saline. The protein expression of Bax and Bcl-2 in neurons was measured at 14 days after operation. A semi-quantitative analysis of Bax and Bcl-2 proteins was performed by image analysis technology.

RESULTSThe model group had significantly increased Bax protein expression and significantly reduced Bcl-2 protein expression in spinal cord anterior horn motor neurons and ganglion sensory neurons compared with the sham-operation group (P<0.05). Compared with the model group and sham-operation group, the mecobalamin group had significantly reduced Bax protein expression and significantly increased Bcl-2 protein expression in spinal cord anterior horn motor neurons and ganglion sensory neurons (P<0.05).

CONCLUSIONMecobalamin has anti-apoptotic effect, and it contributes to neurological function recovery possibly by inhibiting the death of injured neurons.

Animals ; Apoptosis ; Male ; Neurons ; cytology ; drug effects ; Peripheral Nerve Injuries ; metabolism ; pathology ; Proto-Oncogene Proteins c-bcl-2 ; Rats ; Rats, Wistar ; Sciatic Nerve ; pathology ; Spinal Cord ; cytology ; Vitamin B 12 ; analogs & derivatives ; pharmacology ; bcl-2-Associated X Protein ; metabolism

OBJECTIVETo explore the effect of electro-acupuncture to improve the bladder function after acute spinal cord injury in rats and its possible mechanism.

METHODSSixty healthy adult male SD rats of SPF grade, with body weight of 220 to 250 g, one week after feeding adaptation, were randomly divided into sham operation group, model group, electro-acupuncture group, electro-acupuncture control group with 15 rats in each group. Sham operation group underwent no stimulation, and the moderate damage model of spinal cord injury were made in other three groups according to modified Allens method. The model group were not treated, electro-acupuncture group were treated with electro-acupuncture on Zhibianxue and Shuidaoxue, and electro-acupuncture control group were treated with electro-acupuncture on 0.5 inch next to Zhibianxue and Shuidaoxue. The frequency of 2/100 Hz, current of 1 mA, stimulation time of 15 min, once a day, left and right alternately stimulate every time, for a total of 7 times. The changes of residual urine volume and urine output in rats at the 1st and the 7th days after operation were observed. And 7 d later, the rats were sacrificed and the injured spinal cord were taken out to observe the apoptosis, and to detect the changes of Bcl-2, Bax, Bad content.

RESULTSAfter modeling,the rats of three groups showed different bladder dysfunction. In electro-acupuncture group and electro-acupuncture control group, the residual urine volume of the 7th day after operation was significant lower than the 1st day after operation (P < 0.001), and there was statistically significant difference on the 7th day after operation between two groups (P < 0.001). Compared with model group, the urine output of electro-acupuncture group and electro-acupuncture control group was significantly increased on the 7th day after operation, and there was sig- nificant difference between electro-acupuncture group and electro-acupuncture control group (P < 0.001). Electro-acupuncture can inhibit apoptosis of spinal cord neurons by TUNEL detection. Postoperative at 7 d, the rate of nerve cell apoptosis in electro -acupuncture group and electro-acupuncture control group was significant increased than model group (P < 0.01, P < 0.05), and there was significant difference between electro-acupuncture group and electro-acupuncture control group (P < 0.005). Compared with model group, the positive expression rate of Bax, Bad decreased (P < 0.01, P < 0.05), and Bcl-2 increased (P < 0.01) in electro-acupuncture group and electro-acupuncture control group,there was significant difference between electro-acupuncture group and electro-acupuncture control group (P < 0.01).

CONCLUSIONElectro-acupuncture can obviously promote the repair of acute spinal cord injury,its mechanism may be through increasing Bcl-2, inhibiting the expression of Bax, Bad, which inhibits the apoptosis of spinal cord neurons.

Animals ; Apoptosis ; Electroacupuncture ; Immunohistochemistry ; In Situ Nick-End Labeling ; Male ; Neurons ; cytology ; physiology ; Rats ; Rats, Sprague-Dawley ; Spinal Cord Injuries ; pathology ; physiopathology ; therapy ; Urinary Bladder ; physiopathology

Spinal cord injury is a serious disabling disease caused by a series of internal and external factors in the field of orthopaedics and neuroscience, which is a big problem for doctors all over the world. Lithium has been used to treat dipolar disorder for over 100 years. It has been reported that lithium is benefit for brain neuron. The treatment effect for spinal cord injury gets more and more attention. Researches indicate that lithium is benefit for spinal cord injury by protecting neuron,reducing after-injury inflammation increasing the produce and release of neurotrophins, stimulating neurogenesis, enhancing autophagy and inhibiting apoptosis. This article summaries advances in mechanism of treatment for spinal cord injury with lithium by reviewing and analyzing researches. Therapy combined with lithium has a good application prospect.
Animals ; Apoptosis ; drug effects ; Humans ; Lithium ; therapeutic use ; Neurons ; cytology ; drug effects ; Spinal Cord Injuries ; drug therapy ; physiopathology