Spinal Cord Injury Model Group Research Articles

Jisuikang formula promotes spinal cord injury repair in rats by activating the YAP/PKM2 signaling axis in astrocytes

To investigate the effect of Jisuikang formula-medicated serum for promoting spinal cord injury (SCI) repair in rats and explore the possible mechanism. Thirty adult SD rats were randomized into sham-operated group, SCI (induced using a modified Allen method) model group, and Jisuikang formula-medicated serum treatment group. After the operations, the rats were treated with normal saline or Jisuikang by gavage on a daily basis for 14 days, and the changes in hindlimb motor function of the rats was assessed with Basso-Beattie-Bresnahan (BBB) scores and inclined-plate test. The injured spinal cord tissues were sampled from the SCI rat models for single-cell RNA sequencing, and bioinformatics analysis was performed to identify the target genes of Jisuikang, spinal cord injury and glycolysis. In the cell experiment, cultured astrocytes from neonatal SD rat cortex were treated with SOX2 alone or in combination with Jisuikang-medicated serum for 21 days, and the protein expressions of PKM2, p-PKM2 and YAP and colocalization of PKM2 and YAP in the cells were analyzed with Western blotting and immunofluorescence staining, respectively. The SCI rats with Jisuikang treatment showed significantly improved BBB scores and performance in inclined-plate test. At the injury site, high PKM2 expression was detected in various cell types. Bioinformatic analysis identified the HIPPO-YAP signaling pathway as the target pathway of Jisuikang. In cultured astrocytes, SOX2 combined with the mediated serum, as compared with SOX2 alone, significantly increased PKM2, p-PKM2 and YAP expressions and entry of phosphorylated PKM2 into the nucleus, and promoted PKM2 and YAP co-localization in the cells. Jisuikang formula accelerates SCI repair in rats possibly by promoting aerobic glycolysis of the astrocytes via activating the PKM2/YAP axis to induce reprogramming of the astrocytes into neurons.

Long non-coding RNA-small nucleolar RNA host gene 7 regulates inflammatory responses following spinal cord injury by regulating the microRNA-449a/TNF-α-induced protein 3-interacting protein 2 axis

ABSTRACT The current study aimed to explore the anti-inflammatory effects of long non-coding RNA-small nucleolar RNA host gene 7 (lncRNA-SNHG7) and its mechanism in spinal cord injury (SCI) models. SCI models were established both in vivo and in vitro. Reverse transcription-quantitative PCR was performed to determine the expression levels of lncRNA-SNHG7 in SCI models. Bioinformatics analysis and dual-luciferase reporter assays were carried out to confirm the interaction between lncRNA-SNHG7 with microRNA (miR)-499a and TNF-α-induced protein 3-interacting protein 2 (TNIP2). In addition, cell viability, apoptosis, and the secretion of inflammatory cytokines were assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, flow cytometric analysis, and enzyme linked immunosorbent assay (ELISA), respectively. The results showed that lncRNA-SNHG7 was markedly downregulated in the SCI model group. LncRNA-SNHG7 directly bound to miR-499a, which in turn directly targeted TNIP2. In addition, TNIP2 was significantly decreased in SCI rats and lipopolysaccharide (LPS)-treated PC-12 cells. The in vitro results in PC-12 cells revealed that lncRNA-SNHG7 overexpression attenuated neuronal cell death and SCI-mediated inflammatory responses by regulating miR-449a expression. Furthermore, miR-499a knockdown inhibited LPS-induced PC-12 cell injury by targeting TNIP2. In conclusion, lncRNA-SNHG7 modulates the apoptosis and inflammation of PC-12 cells by regulating the miR-449a/TNIP2/NF-κB signaling pathway.

P2Y2 Receptor Mediated Neuronal Regeneration and Angiogenesis to Affect Functional Recovery in Rats with Spinal Cord Injury.

The aim of this study was to investigate the effect of the P2Y2 receptor (P2Y2R) signaling pathway on neuronal regeneration and angiogenesis during spinal cord injury (SCI). The rats were randomly divided into 3 groups, including the sham+dimethyl sulfoxide (DMSO), SCI+DMSO, and SCI+P2Y2R groups. The SCI animal models were constructed. A locomotor rating scale was used for behavioral assessments. The apoptosis of spinal cord tissues was detected by TUNEL staining. The expression levels of P2Y2R, GFAP, nestin, Tuj1, and CD34 were detected by immunofluorescence staining, and the expression levels of TNF-α, IL-1β, and IL-6 were detected by enzyme-linked immunosorbent assay. The locomotor score in the model group was significantly lower than the sham group. The expression of P2Y2R was increased after SCI. The expression levels of TNF-α, IL-1β, and IL-6 were increased remarkably in the SCI model group compared with the sham group. The P2Y2R inhibitor relieved neuronal inflammation after SCI. Compared with the sham group, the apoptotic rate of spinal cord tissue cells in the model group was significantly increased. The P2Y2R inhibitor reduced the apoptosis of the spinal cord tissue. The expressions of CD34, Tuj1, and nestin in the model group were decreased, while the expressions of GFAP and P2Y2R were increased. The P2Y2R inhibitor reversed their expression levels. The P2Y2R inhibitor could alleviate SCI by relieving the neuronal inflammation, inhibiting the spinal cord tissue apoptosis, and promoting neuronal differentiation and vascular proliferation after SCI. P2Y2R may serve as a target for the treatment of SCI.

The effects of GelMA hydrogel on nerve repair and regeneration in mice with spinal cord injury.

BackgroundTo determine the effects of gelatin methacryloyl (GelMA) hydrogel on nerve repair and regeneration in mice with spinal cord injury (SCI).MethodsA total of 30 ICR mice (6–8 weeks old) were randomly assigned into the control group, the model group, and the experimental group via the random digits table method. There were 10 mice in each group. All mice underwent a T8 laminectomy. For mice in the experimental group and the model group, after the T8 laminectomy, SCI models were constructed by clamping the mice spinal cord tissue for 1 minute using an aneurysm clip (25 g). Additionally, the SCI area of each mouse in the experimental group was locally injected with 0.05–0.7 mL GelMA hydrogel [10% (w/v)] and photocrosslinking was initiated under a blue light source with a wavelength of 405 nm. The exercise performance of each mouse was tested via the bedside mobility scale (BMS) on post-operative days 1, 3, 7, and 14. After 14 days, mice were sacrificed and the dorsal root ganglion (DRG) sensory neurons were isolated and cultured for 3 days in vitro. The axon lengths of the neurons were then evaluated. Immunohistochemical staining was performed to assess the development of syringomyelia in the area. Western blots (WB) and immunofluorescence staining were performed to quantify the expression of glial fibrillary acidic protein (GFAP), growth associated protein (GAP)43, and nestin in the DRG neurons from each group of mice.ResultsCompared with mice in the control group, mice in the SCI model group showed a notable decrease in exercise ability, while the exercise ability of mice in the experimental group recovered markedly after treatment with GelMA hydrogel. Administration of GelMA hydrogel lengthened the axon of DRG neurons in mice and reduced the area of syringomyelia. Furthermore, GelMA hydrogel inhibited scar formation and promoted the recovery of neurological function by upregulating GAP43 and nestin expression and downregulating GFAP expression.ConclusionsIn mice with SCI, local injection of GelMA hydrogel strongly inhibited scar formation, reduced the area of syringomyelia, and promoted nerve regeneration and recovery of limb movement function.

Inhibition of lncRNA H19/miR-370-3p pathway mitigates neuronal apoptosis in an in vitro model of spinal cord injury (SCI).

BackgroundSpinal cord injury (SCI) is the most serious complication of spinal injury, often leading to severe dysfunction of the limbs below the injured segment. Conventional therapy approaches are becoming less and less effective, and gene therapy is a new research direction by now.MethodsThe Sprague-Dawley rats were haphazardly assigned to two groups, namely sham group and SCI model group, and lncRNA H19 and miR-370-3p levels were investigated using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Correlation between lncRNA H19 and miR-370-3p was ascertained by luciferase report assay and RT-qPCR. After transfection with si-H19, miR-370-3p inhibitor, negative controls (NC), or both, primary spinal neurons were subjected to the simulation of lipopolysaccharide (LPS) for inducing in vitro model of SCI. Cell viability, apoptotic rate, caspase-3 activity, Bax and Bcl-2 protein, ROS generation, TNF-α, IL-1β, and IL-6 protein, as well as IκBα and p65 phosphorylation ratio were evaluated adopting 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), apoptosis, caspase-3 activity, ROS generation, and western blot assays, thereby searching for the specific action mechanism on LPS-induced spinal never injury.ResultsSCI resulted in lncRNA H19 higher expression and miR-370-3p lower expression. LPS simulation raised a series of cellular biological changes, such as decreased viability, promoted apoptosis, generated ROS, and released inflammatory factors. lncRNA H19 inhibition reversed above LPS-induced changes. Besides, as the downstream target of lncRNA H19, miR-370-3p was oppositely regulated by lncRNA H19. The above biological changes induced by lncRNA H19 inhibition were reversed by miR-370-3p upregulation. Moreover, lncRNA H19 inhibition could block NF-κB pathway through miR-370-3p upregulation.ConclusionInhibition of lncRNA H19/miR-370-3p mitigated spinal neuron apoptosis in an in vitro model of SCI. This provided the possibility for clinical use of gene therapy.

Effect and mechanism of glycyrrhizin on glial scar formation after spinal cord injury in rats

To explore the effect and potential mechanism of glycyrrhizin (GL) by inhibiting high mobility group box 1 (HMGB1) on glial scar formation after spinal cord injury (SCI) in rats. Seventy-two female Sprague Dawley rats were randomly divided into sham group ( n=12), SCI model group (SCI group, n=36), GL intervention group (SCI+GL group, n=12), and nuclear factor κB (NF-κB) inhibitor [pynolidine dithiocarbamate (PDTC)] intervention group (SCI+PDTC group, n=12). The SCI models of SCI group, SCI+GL group, and SCI+PDTC group were made by modified Allen's method, the sham group was only exposed the spinal cord without any injury. First of all, Basso-Beattie-Bresnahan (BBB) score of hind limbs and slope test were performed in SCI group at 1, 2, and 3 weeks after operation; Western blot was used to detect the expressions of glial fibrillary acidic protein (GFAP) and HMGB1 proteins. Compared with the sham group, the most significant time point in the SCI group was selected for subsequent experiment, in which the most significant glial scar was formed. Then, behavioral tests (BBB score of hind limbs and slope test), histological observation of spinal cord tissue structure, Western blot detection of HMGB1, GFAP, and NF-κB proteins, and immunohistochemical staining observation of GFAP and chondroitin sulfate proteoglycan (CSPG) were used to explore the effect of GL on the formation of glial scar after SCI and its potential mechanism. The BBB score and slope angle of the SCI group increased gradually with time, which were significantly lower than those of the sham group at each time point ( P<0.05). Western blot detection showed that the relative expressions of HMGB1 and GFAP proteins in the SCI group at 1, 2, and 3 weeks after operation were significantly higher than those in sham group ( P<0.05). The change was most obvious at 3 weeks after SCI, therefore the spinal cord tissue was selected for subsequent experiments at this time point. At 3 weeks after operation, compared with the SCI group, BBB score and slope angle of SCI+GL group significantly increased ( P<0.05); the relative expressions of HMGB1, GFAP, and NF-κB proteins detected by Western blot and the expressions of GFAP and CSPG proteins detected by immunohistochemical staining significantly decreased ( P<0.05); the disorder of spinal cord tissue by HE staining improved, inflammatory cell infiltration reduced, and glial scar formation decreased. At 3 weeks after operation, the expressions of NF-κB, GFAP, and CSPG proteins of the SCI+PDTC group significantly reduced when compared with the SCI group ( P<0.05); and the expression of NF-κB protein significantly decreased and the expressions of GFAP and CSPG proteins significantly increased when compared with the SCI+GL group ( P<0.05). After SCI in rats, the application of GL to inhibit the expression of HMGB1 can reduce the expression of GFAP and CSPG in the injured spinal cord, then reduce the formation of glial scars and promote the recovery of motor function of the hind limbs, and GL may play a role in inhibiting glial scar through HMGB1/NF-κB pathway.

Electroacupuncture Promoting Axonal Regeneration in Spinal Cord Injury Rats via Suppression of Nogo/NgR and Rho/ROCK Signaling Pathway.

PurposeTo observe the changes of Nogo/NgR and Rho/ROCK signaling pathway-related gene and protein expression in rats with spinal cord injury (SCI) treated with electroacupuncture (EA) and to further investigate the possible mechanism of EA for treating SCI.MethodsAllen’s method was used to create the SCI rat model. Sixty-four model rats were further subdivided into four subgroups, namely, the SCI model group (SCI), EA treatment group (EA), blocking agent Y27632 treatment group (Y27632) and EA+blocking agent Y27632 treatment group (EA+Y), according to the treatment received. The rats were subjected to EA and/or blocking agent Y27632 treatment. After 14 days, injured spinal cord tissue was extracted for analysis. The mRNA and protein expression levels were determined by real-time fluorescence quantitative PCR and Western blotting, respectively. Cell apoptosis changes in the spinal cord were evaluated by in situ hybridization. Hindlimb motor function in the rats was evaluated by Basso-Beattie-Bresnahan assessment methods.ResultsExcept for RhoA protein expression, compared with the SCI model group, EA, blocking agent Y27632 and EA+blocking agent Y27632 treatment groups had significantly reduced mRNA and protein expression of Nogo-A, NgR, LINGO-1, RhoA and ROCK II in spinal cord tissues, increased mRNA and protein expression of MLCP, decreased p-MYPT1 protein expression and p-MYPT1/MYPT1 ratio, and caspase3 expression, and improved lower limb movement function after treatment for 14 days (P<0.01 or <0.05). The combination of EA and the blocking agent Y27632 was superior to EA or blocking agent Y27632 treatment alone (P < 0.01 or <0.05).ConclusionEA may have an obvious inhibitory effect on the Nogo/NgR and Rho/ROCK signaling pathway after SCI, thereby reducing the inhibition of axonal growth, which may be a key mechanism of EA treatment for SCI.

Methotrexate remediates spinal cord injury in vivo and in vitro via suppression of endoplasmic reticulum stress-induced apoptosis.

It has been suggested that endoplasmic reticulum stress (ERS) may induce apoptosis following spinal cord injury (SCI). Methotrexate (MTX) has been used as a long-term therapy regimen for rheumatoid arthritis. However, it is not clear whether MTX remediates SCI by inhibiting ERS. In the present study, to establish an in vitro ERS cell model, PC12 cells were pre-incubated with triglycerides (TG). MTT assays revealed that treatment with 1, 2.5, 5 and 10 µM TG decreased PC12 cell viability in a dose-dependent manner. Additionally, MTX treatment significantly reversed the TG-induced decrease in cell viability and increased apoptosis according to the flow cytometry assay (P<0.05). Notably, western blotting indicated that MTX significantly decreased levels of glucose-regulated protein (GRP)78, CCAAT-enhancer-binding protein homologous protein (CHOP) and caspase-12 expression (P<0.05), which were increased following treatment with TG. Furthermore, the in vivo role of MTX in a rat model of SCI was evaluated. The motor behavioral function of rats was improved following treatment with MTX according to Basso, Beattie and Bresnahan scoring (P<0.05). Terminal deoxynucleotidyl-transferase-mediated dUTP nick end staining indicated that there were no apoptotic cells present in sham rats. In the SCI model group, apoptotic cells were observed at day 7; however, the number of apoptotic cells was reduced following an additional 7 days of MTX administration. Furthermore, levels of ERS-associated proteins, including caspase-3, activating transcription factor 6, serine/threonine-protein kinase/endoribonuclease inositol-requiring enzyme 1 α, eukaryotic initiation factor 2 α and GRP78, were significantly increased following SCI; however, administration of MTX for 7 days significantly reversed this effect (P<0.05, P<0.01 and P<0.001). Therefore, MTX may improve SCI by suppressing ERS-induced apoptosis in vitro and in vivo.

Lentivirus-mediated silencing of the CTGF gene suppresses the formation of glial scar tissue in a rat model of spinal cord injury

Background ContextOne of the many reactive changes following a spinal cord injury (SCI) is the formation of a glial scar, a reactive cellular process whereby glial cells accumulate and surround the central nervous system injury sites to seal in the wound. Thus, the inhibition of glial scar is of great importance for SCI recovery. PurposeThis study aimed to explore the effect of lentivirus-mediated silencing of the CTGF gene on the formation of glial scar tissue in a rat model of SCI. Study DesignThis is a prospective study. Study SampleA total of 56 Wistar female rats aged 8 weeks were randomly selected for this study. Outcome MeasuresThe motor function of the rats was assessed using the Basso, Beattie, and Bresnahan (BBB) functional scale, footprint analysis of gait, and the Basso Mouse Scale (BMS). Quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemistry were performed to detect the mRNA and protein expressions of glial fibrillary acidic protein (GFAP), vimentin, fibronectin, and laminin in the spinal cord tissues. MethodsA rat model of SCI was successfully established. Fifty-six male Wistar rats were randomly selected and assigned into four groups (14 rats in each group): the sham operation group, the SCI model group, the negative control (NC) group (SCI rats transfected with empty vector plasmids), and the siRNA-CTGF group (SCI rats transfected with lentivirus CTGF siRNA). ResultsThe SCI rats showed decreased activity and were dragging their bodies while moving. Compared with the sham operation group, the BBB and BMS scores in the SCI model, NC, and siRNA-CTGF groups significantly decreased. However, the BBB and BMS scores in the siRNA-CTGF group were higher than those in the SCI model and NC groups. The mRNA and protein expressions of GFAP, vimentin, fibronectin, and laminin significantly increased in the SCI model, NC, and siRNA-CTGF groups in comparison with those in the sham operation group. Furthermore, the mRNA and protein expressions of GFAP, vimentin, fibronectin, and laminin in the siRNA-CTGF group were lower than those in the SCI model and NC groups 28 days after transfection. ConclusionsThese findings indicate that lentivirus-mediated silencing of the CTGF gene can suppress the formation of glial scar tissue after SCI.

Protective effect of geraniol inhibits inflammatory response, oxidative stress and apoptosis in traumatic injury of the spinal cord through modulation of NF-κB and p38 MAPK.

Geraniol is a type of monoterpenoid with a rose scent and a slightly sweet flavor. It is found in the volatile oil of various plants, and has anti-inflammatory and anti-oxidant effects. The present study aimed to investigate the protective effect of geraniol in inhibiting the inflammatory response, oxidative stress and apoptosis in traumatic spinal cord injury (SCI), as well as to analyze the mechanism underlying its effect. Adult male Sprague-Dawley rats were induced to traumatic SCI through a surgical procedure and were defined as the SCI model group. SCI or normal rats were then administered 250 mg/kg/day geraniol for 4 weeks. The Basso, Beattie and Bresnahan (BBB) test and the spinal cord water content were used to analyze the effect of geraniol against traumatic SCI in rats. The inflammatory response, oxidative stress, and caspase-9 and -3 activities were measured using commercial ELISA kits. In addition, the associated mechanism was analyzed, using western blot analysis to determine the protein expression levels of nuclear factor (NF)-κB and p38 mitogen-activated protein kinase (MAPK). The results of the present study demonstrated that BBB scores were significantly increased and the spinal cord water content was significantly inhibited in SCI rats after 3 weeks of geraniol treatment. Furthermore, the inflammatory response, oxidative stress, and the caspase-9 and -3 activities were significantly suppressed upon treatment with geraniol. Finally, the mechanism of geraniol against traumatic SCI downregulated the NF-κB and p38 MAPK pathways in SCI rats. Therefore, the protective effect of geraniol is suggested to inhibit the inflammatory response, oxidative stress and apoptosis in traumatic SCI through the modulation of NF-κB and p38 MAPK.

Expression of adrenomedullin in rats after spinal cord injury and intervention effect of recombinant human erythropoietin.

The expression of adrenomedullin (ADM) in injured tissue of rat spinal cord was observed and the effect of recombinant human erythropoietin was analyzed. A total of 45 Sprague-Dawley rats were selected and divided into 3 equal groups including, a sham-operation group in which rats received an excision of vertebral plate; a spinal cord injury model group and a recombinant human erythropoietin group in which rats with spinal cord injury received a caudal vein injection of 300 units recombinant human erythropoietin after injury. Hematoxylin and eosin staining was performed to observe the spinal cord injury conditions. Immunohistochemical staining was performed to observe the expression of ADM. Pathologic changes in the group of recombinant human erythropoietin at various times were significantly less severe than those in the group of spinal cord injury model. The expression of ADM was increased particularly in the group of recombinant human erythropoietin (P<0.01). The improved Tarlov scores of the group of spinal cord injury model and the group of recombinant human erythropoietin were lower than those of the sham-operation group at 3, 6 and 9 days (P<0.01). Thus, the recombinant human erythropoietin is capable of alleviating the secondary injury of spinal cord. One of the mechanisms may be achieved by promoting the increase of ADM expression.

Effect of kidney-reinforcing and marrow-beneficial Chinese medicine on bone metabolism-related factors following spinal cord injury in rats.

The present study aimed to investigate the effect of traditional Chinese kidney reinforcing and marrow-beneficial medicine (KRMB) on the prevention and treatment of abnormal bone metabolism and osteoporosis (OP) resulting from spinal cord injury (SCI). Rat models of OP following SCI were surgically established. The rats were randomly divided into five groups: Normal; sham operation + KRMB; normal + KRMB; SCI + KRMB; and SCI model group. Bone mineral density (BMD), and the expression of bone gamma-carboxyglutamic-acid containing protein (BGP), hepcidin mRNA and bone sialoprotein (BSP) were recorded at 1, 2, 4, 6, 8 and 10 weeks after the operation. BMD expression in the SCI model group was significantly lower compared with the normal, sham + KRMB and normal + KRMB groups at 4, 6, 8 and 10 weeks (P<0.01), and was significantly lower than that in the SCI + KRMB group at 6 (P<0.05), 8 and 10 weeks (P<0.01). The level of serum BGP in the SCI model group was significantly higher compared with the normal, sham + KRMB and normal + KRMB groups at each time point (P<0.01), and lower than the SCI + KRMB group (P<0.01). The SCI + KRMB group was significantly higher than the normal, sham operation + KRMB and normal + KRMB groups (P<0.01). Hepcidin mRNA expression in the rat livers in the normal, sham + KRMB and normal + KRMB group was significantly higher than that in the SCI + KRMB group and SCI model group at each time point (P<0.01). Hepcidin mRNA expression in the SCI + KRMB group was significantly higher than that in the SCI model group at 1 week (P<0.01), and significantly higher than the SCI model group at 2, 4, 6, 8 and 10 weeks (P<0.01). BSP expression in the SCI model group was significantly higher than that in the normal, sham + KRMB and normal + KRMB groups at each time point (P<0.01). BSP expression in SCI model group was higher than that in the SCI + KRMB group at 1 (P<0.05), 2, 4, 6, 8 and 10 weeks (P<0.01). In conclusion, KRMB traditional Chinese medicine may have a curative effect on secondary OP resulting from SCI.

Treatment with bone marrow mesenchymal stem cells combined with plumbagin alleviates spinal cord injury by affecting oxidative stress, inflammation, apoptotis and the activation of the Nrf2 pathway.

The aim of the present study was to investigate the protective effect exerted by bone marrow mesenchymal stem cells (BMSCs) in combination with plumbagin on spinal cord injury (SCI) and explore the mechanism behind this protective effect. Firstly, BMSCs were extracted from male Sprague-Dawley rats, cultured in vitro, and identified by hematoxylin. Sprague-Dawley rats were then randomly divided into a control group, SCI model group, BMSC-treated group, a plumbagin-treated group, and a BMSC and plumbagin-treated group. After treatment with BMSCs combined with plumbagin, a Basso, Beattie and Bresnahan (BBB) test was carried out and the spinal cord water content was examined in order to analyze the effect of BMSCs combined with plumbagin on SCI. The myeloperoxidase (MPO), superoxide dismutase (SOD), malondialdehyde (MDA), nuclear factor-κB (NF-κB) p65 unit, tumor necrosis factor-α (TNF-α) levels were also detected. Moreover, nuclear factor erythroid 2‑related factor 2 (Nrf2), phosphoinositide 3-kinase (PI3K), phosphorylated (p-)Akt, p-p38 mitogen-activated protein kinase (MAPK), and p-extracellular-signal-regulated kinase (ERK) protein expression levels were measured using western blot analysis. Treatment with BMSCs combined with plumbagin significantly improved locomotor recovery and reduced the spinal cord water content after SCI. The increased MPO, MDA, NF-κB p65 and TNF-α levels were significantly suppressed and the decreased SOD was significantly increased in SCI rats. The suppression of Nrf2, p-Akt and p-ERK, as well as the promotion of p-p38 MAPK, were reversed by treatment with BMSCs combined with plumbagin. These effects suggest that treatment with BMSCs combined with plumbagin alleviates SCI through its effects on oxidative stress, inflammation, apoptotis and activation of the Nrf2 pathway.

Neuroprotective effects of the Buyang Huanwu decoction on functional recovery in rats following spinal cord injury

Background: The Buyang Huanwu decoction (BYHWD) is a traditional Chinese herbal prescription and has been used in China to treat spinal cord injury (SCI) for hundreds of years. Clinical trials have shown that BYHWD improves the outcome of SCI in clinical trials, but the mechanisms are not known. This study observed the neuroprotective effects of BYHWD on spinal nerve cells after SCI and investigated possible mechanisms.Materials and methods: Forty female Wistar rats were randomized equally to four groups treated by sham injury, SCI, BYHWD, or methylprednisolone (MP). The Basso, Beattie, and Bresnahan (BBB) score was used to evaluate hind-limb locomotor function. Neuron apoptosis was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling staining and caspase-3, Bax, and Bcl-2 mRNA and protein expression were evaluated by real-time quantitative polymerase chain reaction and Western blotting, respectively.Results: In the sham group, walking was mildly abnormal after anesthesia but recovered completely in 2 days. The BBB score in the SCI model group was significantly different from that in the sham group. The BBB scores of rats in both the BYHWD and MP groups were significantly higher than scores of rats in the SCI group. BYHWD had an antiapoptosis effect, as shown by significant decreases in expression of caspase-3 and Bax and increase in Bcl-2 expression.Conclusion: BYHWD treatment restored hind-limb motor function of rats with SCI. The neuroprotective effect of BYHWD was associated with modulation of the expression of apoptosis-related proteins.

Neuroprotective effect of apigenin in rats after contusive spinal cord injury

Apigenin, a common plant flavonoid, has been extensively studied and showed a wide variety of beneficial effects. The aim of this study was to determine the therapeutic efficacy of starting apigenin treatment 3day after spinal cord injury (SCI) in rat and to investigate the underlying mechanism. SCI was induced using the modified weight-drop method in Sprague-Dawley rats. The SCI animals were randomly assigned to five groups: sham control group, SCI model group, the methylprednisolone sodium succinate (MPSS) group, the 10mg/kg apigenin treatment group and the 20mg/kg apigenin treatment group. First, neuronal function after SCI was evaluated with Basso Beattie Bresnahan locomotor rating scale (BBB) and the result showed that injured animals treated with apigenin showed a significant increase in BBB scores. To explore the underlying mechanism, antioxidative effect of apigenin was assessed by measuring malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities after SCI. Apigenin treatment reversed the decrease of SOD and GSH-Px activity, and the increase of MDA level caused by SCI, suggesting its antioxidative role in response to the injury. In addition, apigenin treatment decreased serum interleukin-1β, tumor necrosis factor-α and intercellular adhesion molecule-1 release after SCI, suggesting an anti-inflammatory effect of apigenin. Finally, apigenin treatment affected the expression level of apoptosis-related gene Bax, Bcl-2 and caspase-3, which indicated its antiapoptosis role after SCI. Our data suggest that apigenin significantly promotes the recovery of rat neuronal function after SCI, which is associated with its antioxidative, anti-inflammatory and antiapoptotic properties.

Therapeutic effects of NogoA vaccine and olfactory ensheathing glial cell implantation on acute spinal cord injury

Therapeutic effects of NogoA vaccine and olfactory ensheathing glial cell implantation on acute spinal cord injury Zhicheng Zhang, Fang Li, Tiansheng Sun, Dajiang Ren, Xiumei Liu PLA Institute of Orthopedics, Beijing Army General Hospital, Beijing, People&#39;s Republic of China Background: Many previous studies have focused on the effects of IN-1, a monoclonal antibody that neutralizes Nogo (a neurite growth inhibitory protein), on neurologic regeneration in spinal cord injury (SCI). However, safety problems and the short half-life of the exogenous antibody are still problematic. In the present study, the NogoA polypeptide was used as an antigen to make a therapeutic NogoA vaccine. Rats were immunized with this vaccine and were able to secrete the polyclonal antibody before SCI. The antibody can block NogoA within the injured spinal cord when the antibody gains access to the spinal cord due to a compromised blood&ndash;spinal cord barrier. Olfactory ensheathing glial cell transplantation has been used in a spinal cord contusion model to promote the recovery of SCI. The present study was designed to verify the efficacy and safety of NogoA polypeptide vaccine, the effects of immunotherapy with this vaccine, and the synergistic effects of the vaccine and olfactory ensheathing glial cells in repair of SCI. Methods: A 13-polypeptide fragment of NogoA was synthesized. This fragment was then coupled with keyhole limpet hemocyanin to improve the immunogenicity of the polypeptide vaccine. Immunization via injection into the abdominal cavity was performed in rats before SCI. The serum antibody level and ability of the vaccine to bind with Nogo were detected by enzyme-linked immunosorbent assay. The safety of the vaccine was evaluated according to the incidence and severity of experimental autoimmune encephalomyelitis. Olfactory ensheathing glia cells were obtained, purified, and subsequently implanted into a Wistar rat model of thoracic spinal cord contusion injury. The rats were divided into four groups, ie, an SCI model group, an olfactory ensheathing glia group, a vaccine group, and a combined treatment group. Animal behavior, histopathology, and axonal regeneration were compared between the four treatment groups. Results: The antibody against the polypeptide was detected in rat serum by enzyme-linked immunosorbent assay. Experimental autoimmune encephalomyelitis was not found in the immunized rats. Three months after injury, Basso, Beattie, Bresnahan scores and nerve fiber counts in biotinylated dextran amine nerve tracing studies were significantly better in the combined treatment group than in the other groups. Conclusion: The polypeptide NogoA vaccine can stimulate the humoral immune system to produce antibodies against the NogoA polypeptide. The binding reaction between the antibody and antigen was shown in ex vivo experiments. No evidence was found to suggest a relationship between NogoA vaccination and increased risk of experimental autoimmune encephalomyelitis. The combined strategy of olfactory ensheathing glial cell implantation and NogoA vaccination may promote regeneration of axons and functional recovery in the spinal cord contusion injury model. This study may provide a new strategy for combining modalities to enhance axonal regeneration and a better balance of the CNS microenvironment after SCI. Keywords: spinal cord injury, immunotherapy, cell transplantation, olfactory ensheathing glial cells, NogoA, vaccine

Neuroprotective effect of salidroside on hemisection-induced spinal cord injury in rats

The effect of salidroside on hemisection-induced spinal cord injury (SCI) in rats was investigated. The Sprague Dawley (SD) rats were randomly divided into six groups: Sham control group, SCI model group, the methylprednisolone sodium succinate (MPSS) group, the salidroside-low dosage group, the salidroside-moderate dosage group and the salidroside-high dosage group. The SD rats were hemisected at spinal cord at the T8 vertebra to establish SCI models. 24 h after operation, different dosage of salidroside increased the superoxide anion (O2−) level and superoxide dismutase (SOD) activity, and reduced malondialdehyde (MDA) content. Noticeably, salidroside at the 100 mg/kg dosage exhibited similar effects as MPSS, which has been frequently used for clinical acute SCI. These results suggested that salidroside can significantly suppress oxidation in acute SCI. Key words: Salidroside, spinal cord injury (SCI), oxidation.

English

The effect of salidroside on inflammatory factors in rats with hemisection-induced spinal cord injury (SCI) was studied. The Sprague-Dawley (SD) rats were divided into six groups: Sham control group, SCI model group, the methylprednisolone sodium succinate (MPSS) treatment group, the salidroside-low dosage treatment group, the salidroside-moderate dosage treatment group and the salidroside-high dosage treatment group. The C2 hemisection method was developed to establish SCI models. 24 h after operation, different dosage of salidroside treatment inhibited some inflammatory factors such as, interleukin-1 beta (IL-1β), tumor necrosis factor alpha (TNF-α) and Intercellular adhesion molecule 1 (ICAM-1). These results suggested that salidroside can significantly inhibit the increased inflammatory factors in acute SCI. Key words: Salidroside, spinal cord injury (SCI), inflammatory factors.

The effect of astaxanthin (AST) on Neurotrophin-3 (NT-3) expression in rats after compressive spinal cord injury (SCI)”

A great deal of this research has been centered on the neuroprotective benefits of astaxanthin. However, no studies have suggested that astaxanthin has therapeutic potential for SCI and the mechanisms underlying astaxanthin neuroprotection are not fully understood. The aim of this study was to determine the therapeutic efficacy of starting astaxanthin treatment 1 day after compressive spinal cord injury (SCI) in rat and to investigate the underlying mechanism. The SD rats were randomly divided into four groups namely: Sham control group, SCI model group, the methylprednisolone sodium succinate (MPSS) group and the astaxanthin treatment group. Western blot analysis and Reverse transcription-polymerase chain reaction (RT-PCR) were performed to detect the expression of the Neurotrophin-3 (NT-3). Noticeably, astaxanthin at the 80 mg/kg dosage exhibited similar effects as MPSS, which has been frequently used for clinical acute SCI. These results suggested that astaxanthin could increase the expression of NT-3 in SCI. Key words: Astaxanthin, spinal cord injury, neurotrophin-3.

Effect of salidroside on Bcl-2/Bax protein levels in rats with hemisection- induced spinal cord injury

The effect of salidroside on Bcl-2/Bax protein levels in rats with hemisection-induced spinal cord injury (SCI) was studied. The Sprague Dawley (SD) rats were randomly divided into six groups: Sham operation group, SCI model group, methylprednisolone sodium succinate (MPSS) treatment group, salidroside-low dosage treatment group, salidroside-moderate dosage treatment group, and salidroside-high dosage treatment group. The SD rats were hemisected at the spinal cord, at the T8 vertebra to establish SCI model. 24 h after operation, different dosage of salidroside increased and reduced the protein levels. Noticeably, salidroside at the 100 mg/kg dosage exhibited similar effects as MPSS, which has been frequently used for clinical acute SCI. These results suggested that salidroside can significantly inhibit apoptosis in acute SCI. Key words: Salidroside, spinal cord injury (SCI), Bcl-2/Bax, apoptosis.