Basso, Beattie And Bresnahan Research Articles

Effects of ganglioside G(M1) and erythropoietin on spinal cord lesions in rats: functional and histological evaluations

OBJECTIVE:To evaluate the functional and histological effects of ganglioside G(M1) and erythropoietin after experimental spinal cord contusion injury.METHODS:Fifty male Wistar rats underwent experimental spinal cord lesioning using an NYU-Impactor device and were randomly divided into the following groups, which received treatment intraperitoneally. The G(M1) group received ganglioside G(M1) (30 mg/kg); the erythropoietin group received erythropoietin (1000 IU/kg); the combined group received both drugs; and the saline group received saline (0.9%) as a control. A fifth group was the laminectomy group, in which the animals were subjected to laminectomy alone, without spinal lesioning or treatment. The animals were evaluated according to the Basso, Beattie and Bresnahan (BBB) scale, motor evoked potential recordings and, after euthanasia, histological analysis of spinal cord tissue.RESULTS:The erythropoietin group had higher BBB scores than the G(M1) group. The combined group had the highest BBB scores, and the saline group had the lowest BBB scores. No significant difference in latency was observed between the three groups that underwent spinal cord lesioning and intervention. However, the combined group showed a significantly higher signal amplitude than the other treatment groups or the saline group (p<0.01). Histological tissue analysis showed no significant difference between the groups. Axonal index was significantly enhanced in the combined group than any other intervention (p<0.01).CONCLUSION:G(M1) and erythropoietin exert therapeutic effects on axonal regeneration and electrophysiological and motor functions in rats subjected to experimental spinal cord lesioning and administering these two substances in combination potentiates their effects.

Therapeutic Potential of Bone Marrow Derived Mesenchymal Stem Cells in Modulating Astroglyosis of Surgical Induced Experimental Spinal Cord Injury

Background: Spinal cord injury (SCI) unsuccessful regeneration was due to glial scar development. It was a major obstacle to axonal restoration. Safe therapeutic intervention by the use of bone marrow derived stem cells (BMMSCs) transplantation applied in the present study could reduce spinal disability. Material and methods: Forty male albino rats were divided into four groups: GI: negative control (n = 10 rats); GII: positive control after SCI (n = 10 rats); GIII: SCI + BM － MSCs intravenous injected and GIV: SCI + BM － MSCs intra lesion injected (n = 10 rats in each group). The samples were taken from spinal cord tissues around the region of injury and were subjected to histological, immunohistochemical assessment. RNA extraction and real time PCR for detection of nerve regeneration and astrocyte response to the injury were also performed. Results: Clinical improvement occurred by the enhancement in the Basso, Beattie and Bresnahan (BBB) score after SCI. Histological examinations showed positive regenerative responses in GIV compared to GIII. Conclusion: BM-MSCs transplantation has a promising role in enhancing the microenvironment for nerve regeneration through stumbling the glial scaring formation and inflammatory response after chronic spinal cord injury especially by using intra-lesion route injection.

Effects of tacrolimus and erythropoietin in experimental spinal cord lesion in rats: functional and histological evaluation.

Study design:Experimental study with rats.Objective:To evaluate functional and histological effects of tacrolimus (FK 506) and erythropoietin (EPO) after experimental spinal cord contusion injury (SCI).Setting:Brazil.Methods:Wistar rats (n=60) were submitted to SCI with the NYU Impactor system. The control group received saline; the EPO group received EPO; the group EPO+FK 506 received EPO associated with tacrolimus and the group FK 506 received tacrolimus only. The Sham group underwent SCI, but did not receive any drug. Locomotor function was evaluated after SCI by BBB (Basso, Beattie and Bresnahan) weekly and by the motor-evoked potential test in 42 days. The spinal cord was histologically evaluated.Results:There was a significant difference between treated and the control groups from the seventh day on for BBB scores, with no difference between the groups EPO and EPO+FK 506 by the end of the study. There were significant differences between groups for necrosis and bleeding, but not for hiperemia, degeneration and cellular infiltrate. Axon neuron count was different between all groups (P=0.001), between EPO+FK 506 and FK 506 (P=0.011) and between EPO+FK 506 and Sham (P=0.002). Amplitude was significantly different between all groups except between control and sham. For latency, there was no difference.Conclusions:This study did not reveal significant differences in the recovery of locomotor function, or in the histological and electrophysiological analysis in animals treated with EPO and tacrolimus after thoracic SCI.

Effect of rutin on spinal cord injury through inhibition of the expression of MIP-2 and activation of MMP-9, and downregulation of Akt phosphorylation.

Rutin has extensive pharmacological activities, including antibacterial and anti-inflammatory activities, cooling of the blood to inhibit bleeding, reducing capillary wall fragility and anti-influenza activities. However, whether rutin can ameliorate neuropathic function in spinal cord injury (SCI) in constriction-induced peripheral nerve injury remains to be elucidated. In the present study, the potential protective effects of rutin on SCI rats were investigated. Neurological function was examined using the Basso, Beattie and Bresnahan (BBB) scoring system and by measuring the water content of the spinal cord tissue in SCI rats. SCI-induced programmed cell death was measured using hematoxylin and eosin staining. In addition, the expression of macrophage inflammatory protein-2 (MIP-2) and the activation of matrix metalloproteinase-9 (MMP-9) in the SCI rats were evaluated using ELISA assay kits and zymographic analysis, respectively. The phosphorylation of protein kinase B (p-Akt) was analyzed using a western blot assay. The results demonstrated that administrating rutin began to increase BBB scores and attenuate the spinal cord water content of the SCI rats. Administrating rutin prevented SCI-induced programmed cell death. The SCI rats of in the rutin-treated group were found to exhibit lower expression levels of MIP-2 and p-Akt, reduced MMP-9 activation, compared with the SCI model rats. In conclusion, rutin was demonstrated as a potential protective agent in SCI and enhances the neurotrophic effect by inhibiting the expression of MIP-2 and activation of MMP-9, and downregulating the expression of p-Akt.

Local Delivery of High-Dose Chondroitinase ABC in the Sub-Acute Stage Promotes Axonal Outgrowth and Functional Recovery after Complete Spinal Cord Transection.

Chondroitin sulfate proteoglycans (CSPGs) are glial scar-associated molecules considered axonal regeneration inhibitors and can be digested by chondroitinase ABC (ChABC) to promote axonal regeneration after spinal cord injury (SCI). We previously demonstrated that intrathecal delivery of low-dose ChABC (1 U) in the acute stage of SCI promoted axonal regrowth and functional recovery. In this study, high-dose ChABC (50 U) introduced via intrathecal delivery induced subarachnoid hemorrhage and death within 48 h. However, most SCI patients are treated in the sub-acute or chronic stages, when the dense glial scar has formed and is minimally digested by intrathecal delivery of ChABC at the injury site. The present study investigated whether intraparenchymal delivery of ChABC in the sub-acute stage of complete spinal cord transection would promote axonal outgrowth and improve functional recovery. We observed no functional recovery following the low-dose ChABC (1 U or 5 U) treatments. Furthermore, animals treated with high-dose ChABC (50 U or 100 U) showed decreased CSPGs levels. The extent and area of the lesion were also dramatically decreased after ChABC treatment. The outgrowth of the regenerating axons was significantly increased, and some partially crossed the lesion site in the ChABC-treated groups. In addition, retrograde Fluoro-Gold (FG) labeling showed that the outgrowing axons could cross the lesion site and reach several brain stem nuclei involved in sensory and motor functions. The Basso, Beattie and Bresnahan (BBB) open field locomotor scores revealed that the ChABC treatment significantly improved functional recovery compared to the control group at eight weeks after treatment. Our study demonstrates that high-dose ChABC treatment in the sub-acute stage of SCI effectively improves glial scar digestion by reducing the lesion size and increasing axonal regrowth to the related functional nuclei, which promotes locomotor recovery. Thus, our results will aid in the treatment of spinal cord injury.

Spinal 5-HT3 receptor mediates nociceptive effect on central neuropathic pain; possible therapeutic role for tropisetron

Objectives: To test the analgesic effect of 5-HT-3 receptor antagonist, tropisetron, in a clip compression injury model of spinal cord pain in rats.Methods: Four weeks post compression of the spinal cord at lumbar level, tropisetron was administered intrathecally at 100 μg and 150 μg dosages. Behavioral tests were assessed before administration. Fifteen minutes after injection, behavioral tests were repeated. Randall-Sellitto and plantar test was used for mechanical and thermal hyperalgesia, respectively. Mechanical and cold allodynia were evaluated by Von Frey filament and acetone droplets, respectively. The analgesic effect of tropisetron was compared with intrathecal administration of salicylate. Locomotor score was evaluated by Basso, Beattie and Bresnahan (BBB) test every week after spinal cord injury.Results: Intrathecal administration of tropisetron, decreased hyperalgesia and mechanical allodynia, but not cold allodynia were observed after compression of the spinal cord.Conclusion: Blockade of 5-HT-3 receptors by tropisetron at the spinal level induces an antinociceptive effect on chronic central neuropathic pain and suggests that this compound may have potential clinical utility for the management of central neuropathic pain, particularly in patients with hyperalgesia and tactile allodynia.

A computerized system for the application of Basso, Beattie and Bresnahan scale in Wistar rats.

OBJECTIVES: To develop and test a computer program to assist researchers in assigning scores in the application of the Basso, Beattie and Bresnahan (BBB) scale and to compare these scores when doing so in free, targeted and automated computer-assisted modes. METHOD: To test the program, the participants used the Impactor methodology recommended by the New York University (USA), in which 12 Wistar rats submitted to spinal cord injury were filmed on the 28th day after the injury. Eight researchers from the Laboratory of Medical Investigation, Faculdade de Medicina da Universidade de São Paulo, SP, Brazil took part in the study. The two heads of the laboratory, with 15 years of experience in the application of the scale, were considered the gold standard. RESULTS: The results of the scale application were not significantly different in relation to the gold standard, considering the mean of the evaluators in each method: free, targeted and automated form (with the help of the computer). CONCLUSIONS: The application of the BBB scale in the automated mode, using the computer program, did not present any difference in relation to the gold standard for all the evaluators. Level of Evidence II, Diagnostic Studies.

Carvacrol protects against spinal cord injury in rats via suppressing oxidative stress and the endothelial nitric oxide synthase pathway.

Carvacrol (CAR) is a naturally occurring phenolic monoterpene and has been demonstrated to possess a spectrum of pharmacological actions. The present study was designed to assess the neuroprotection of CAR against spinal cord injury (SCI) in rats and to identify the underlying mechanisms. SCI was induced using the modified weight‑drop method in Wistar rats. CAR or saline was administered at doses of 25, 50 and 100 mg/kg for 46 days. Neuronal function following SCI was evaluated using the Basso, Beattie and Bresnahan (BBB) locomotor rating scale. Spinal cord edema was assessed by measuring the water content in spinal cord tissues. The oxidative indicators, including malondialdehyde, catalase, superoxide dismutase glutathione peroxidase and 8‑isoprotane as well as endothelial nitric oxide synthase (eNOS) activity and caspase‑3 were measured using corresponding commercial kits. The protein expression of eNOS and B cell lymphoma‑2 (Bcl‑2) as well as Bcl‑2‑associated X protein (Bax) was analyzed by western blot analysis. The SCI‑induced rats demonstrated marked reductions in BBB scores. CAR treatment recovered neurological function with decreasing BBB scores. CAR was found to have inhibitory effects on the water content in the spinal cord, oxidative stress, eNOS, nitric oxide production and apoptosis‑associated molecules, including Bax and caspase‑3 as well as promoting Bcl-2 expression in SCI-induced rats. These results suggested that CAR protects against SCI via mediating oxidative stress and the eNOS signaling pathway.

VEGF inhibits the inflammation in spinal cord injury through activation of autophagy

Vascular endothelial growth factor (VEGF) is a secreted mitogen associated with angiogenesis and re-vascularization of spinal cord injury (SCI). VEGF has long been thought to be a potent neurotrophic factor for the survival of spinal cord neuron. However, the neuroprotective mechanism of VEGF is still unclear. The aim of this study was to investigate the effect of VEGF on spinal cord injury and its mechanisms. Young male Wistar rats were subjected to SCI and then VEGF165 were injected directly into the lesion epicenter 24 h post injury. We detected Basso, Beattie and Bresnahan (BBB) scores and numbers of motor neuron via Nissl staining. The expressions of autophagy related protein Beclin1 and LC3B were determined by Western blot and RT-PCR. We also detected the contents of inflammation factors interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α) and interleukin-10(IL-10) in LPS (Lipopolysaccharide) treated spinal neuron-glia co-culture by ELISA. We found that VEGF165 administration increased the BBB score and reduced the loss of motor neuron of rats induced by SCI. VEGF decreased the protein expressions of IL-1β, TNF-α and IL-10 and up-regulated the expressions of Beclin1 and LC3B of rats. In the in vitro study, VEGF165 decreased the levels of IL-1β, IL-10 and TNF-a in the medium of LPS treated spinal neuron-glia co-culture, which was partially blocked by 3-MA, the inhibitor of autophagy. In addition, VEGF165 up-regulate the expressions of Beclin1 and LC3B in co-culture cells. The results suggested that VEGF165 attenuated the spinal cord injury by inhibiting the inflammation and increasing the autophagy function.

Effect of neuroglobin gene-modified bone marrow mesenchymal stem cells on spinal cord injury in rats

Objective To observe the protective effect of neuroglobin gene-modified bone marrow mesenchymal stem cells(BMSCs)on spinal cord injury(SCI)in rats and explore the mechanism. Methods Sixty SD rats were randomly divided into saline group, BMSCs group, Neuroglobin(Ngb)/BMSCs group and blank group, given saline, BMSCs-culture medium, BMSCs-culture medium infected with Ngb after SCI,and nothing respectively.Measurements were evaluated by the Basso,Beattie and Bresnahan (BBB)scores at 1st,3rd,7th,14th and 21st day separately Results The BBB scores at 1st and 3rd day in each group were as follows:blank group(2. 76±0. 50,and 3. 70±0. 76),saline group(2. 72±0. 53,and 4. 06±0. 77), BMSCs group(2. 76±0. 71,and 4. 13±0. 76),and Ngb/BMSCs group(2. 79±4. 20,and 4. 20±0. 82). There was no significant difference among groups. At 7th, 14th and 21st day, the BBB scores in each group were gradually increased:blank group(5. 22±0. 64,6. 16±0. 78,and 7. 54±0. 90), saline group(5. 72±0. 94, 7. 61±0. 76, and 10. 87±0. 91), BMSCs group(5. 87±0. 84, 8. 33±0. 94, and 11. 45±1. 02), and Ngb/BMSCs group(6. 52±0. 95, 9. 78±0. 84, and 13. 33±1. 05).There were statistically significant difference between Ngb/BMSCs group and others(P< 0. 05). Conclusion Neuroglobin gene-modified BMSCs can make injured spinal cord supply stable and a high level Ngb in time, which can obviously help recovery of neural function after SCI in rats. Key words: Neuroglobin; Gene modified; Bone marrow mesenchymal stem cells; Spinal cord injury

Comparative Study on the Effects of Ceftriaxone and Monocytes on Recovery after Spinal Cord Injury in Rat.

Comparison between the efficacy of ceftriaxone and monocytes on improvement of neuron protection and functional recovery after spinal cord injury (SCI) in rat. Rats were randomly divided into three groups of ten. Spinal cord injury was performed on rats under general anesthesia using the weight dropping method. Ceftriaxone was injected intraperitoneally 200 mg/kg/day for seven days after SCI. Monocytes were injected 2 × 105 cells 4 days after SCI. Hind limb motor function was assessed using the Basso, Beattie and Bresnahan (BBB) scale. Corticospinal tract (CST) axons were traced by injection of biotin dextran amine (BDA) into the sensorimotor cortex. There were statistically significant differences in BBB scores in ceftriaxone in comparison to both monocytes receiving and control groups. On the other hand there were statistically significant differences in axon counting in both ceftriaxone and monocytes receiving groups in comparison to control group. Our findings suggest that ceftriaxone improves functional recovery more effective than monocytes in rats after SCI. These results are from an experimental model and validation is required for further investigation.

A modified compression model of spinal cord injury in rats: functional assessment and the expression of nitric oxide synthases.

Study design:Experimental study.Objectives:To investigate a modified compression model of spinal cord injury (SCI) in adult rats by using a room-air- inflated Fogarty balloon catheter.Setting:Kaohsiung, Taiwan.Methods:The rats were divided into injury, sham-operated and control groups. A 2-French Fogarty catheter was passed from the lumbar spine (L3–L4) epidurally, with a mini-laminectomy under the microscope, to the level of thoracic spine (T6–T7). The actual site of the catheter tip was confirmed with X-ray. The balloon of Fogarty catheter then was inflated with room air, 0.2 ml, for 10 min. Mini-laminectomy was performed without inserting the catheter in the sham-operated group. Quantitative neurological outcomes were evaluated with the Basso, Beattie and Bresnahan (BBB) locomotor rating scale daily. The gene expression of nitric oxide synthases (NOSs) of the spinal cord was investigated at the end of the functional assessment.Results:The mean BBB locomotor scores were 10±1.85 and 10±1.85, respectively, on days 1 and 3 in the injury group, and 21 and 20.29±0.69, respectively, in the sham-operated group. There was a significantly increased gene expression of inducible NOS in the SCI group compared with the sham-operated group and control group. Endothelial NOS gene expression was not significantly different among the groups.Conclusion:The functional and molecular assessments show that this modified balloon-compression technique is a reproducible, simple and inexpensive model of SCI in rats.

Synergistic effects of Buyang Huanwu decoction and embryonic neural stem cell transplantation on the recovery of neurological function in a rat model of spinal cord injury.

The aim of the present study was to investigate the therapeutic effect of a combined treatment of Buyang Huanwu decoction (BYHWD), a well-known formula of traditional Chinese medicine, and neural stem cells (NSCs) on spinal cord injury (SCI) and the associated underlying mechanisms. A SCI model was established by surgery via a complete transection of the T10 vertebra of female Sprague-Dawley rats. Gelatin sponges were used to absorb NSCs labeled with the thymidine analog, 5-bromo-2-deoxyuridine (BrdU), and were transferred into the transected spinal cords. BYHWD was administered once a day by introgastric infusion. Motor functions of the hind limbs were evaluated using the 21-point locomotor rating scale developed by Basso, Beattie and Bresnahan (BBB). The fate of the transplanted NSCs under the various conditions was examined by double immunofluorescence staining, using markers for neurons, astrocytes and oligodendrocytes, with BrdU. Ultrastructural changes of the SCI site following the various treatments were examined under a transmission electron microscope. The number of double positive cells for glial fibrillary acidic protein and BrdU in the BYHWD + NSC group was significantly decreased when compared with that in the NSC group (P<0.05). However, the number of cells that were labeled double positive for myelin basic protein and BrdU, as well as neuron specific enolase and BrdU, was greater in the BYHWD + NSC group when compared with the NSC group. Electron microscopy demonstrated that treatment with BYHWD combined with NSCs significantly alleviated demyelination. Results from the BBB motor function test exhibited a significant improvement in the BYHWD + NSC group when compared with the SCI, BYHWD and NSC only groups. In conclusion, the results demonstrated that the traditional Chinese medicine formula, BYHWD, exerted an effect on the differentiation and migration of NSCs. Combining the administration of BYHWD with NSCs was shown to have a synergistic effect on the recovery of neurological function, mitigating the progress of demyelination or ameliorating the recovery of myelination.

Neuroprotective effects of electroacupuncture on early- and late-stage spinal cord injury.

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

Visual bone marrow mesenchymal stem cell transplantation in the repair of spinal cord injury.

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

The Effects of Adipose Tissue-Derived Mesenchymal Stem Cell Transplantation During the Acute and Subacute Phases Following Spinal Cord Injury.

To investigate the effectiveness of rat adipose tissue-derived (rAT) mesenchymal stem cell (MSC) transplantation on the functional restoration and regeneration of spinal cord injury (SCI). Six of 48 Wistar albino rats were sacrificed to obtain MSCs, and the remaining rats were divided randomly into six groups. SCI was performed using the clip compression method. The control and transplantation groups were injected with physiological saline and a rAT-MSC suspension at the injury sites, respectively. Each animal was evaluated using the Basso, Beattie and Bresnahan (BBB) rating system and sacrificed at 28 days post-injury period (p.i.). The regeneration process was evaluated based on immunostaining against β3-tubulin, BDNF, CNTF, and CNPase. rAT-MSC transplantation into the SCI site substantially improved the tissue regeneration and functional recovery (p < 0.05). However, the rAT-MSC transplantation at 9 days p.i. was not more efficient on functional recovery than the transplantation immediately after injury. The expression of β3-tubulin, BDNF and CNTF at the injury site indicated the potential for functional regeneration. The adaptive nature of rat-MSCs enabled the remodulation and regeneration of the lesion site, decreasing the importance of transplantation time in the treatment of SCI.

An Acute Growth Factor Treatment that Preserves Function after Spinal Cord Contusion Injury

Inflammation of the spinal cord after traumatic spinal cord injury (SCI) leads to destruction of healthy tissue. This "secondary degeneration" is more damaging than the initial physical damage and is the major contributor to permanent loss of functions. In our previous study, we showed that combined delivery of two growth factors, vascular endothelial growth factor and platelet-derived growth factor, significantly reduced secondary degeneration after hemisection injury of the spinal cord in the rat. Growth factor treatment reduced the size of the lesion cavity at 30 days, compared to control animals, and further reduced the cavity at 90 days in treated animals, whereas in control animals the lesion cavity continued to increase in size. Growth factor treatment also reduced astrogliosis and reduced macroglia/macrophage activation around the injury site. Treatment with individual growth factors alone had similar effects to control treatments. The present study investigated whether growth factor treatment would improve locomotor behavior after spinal contusion injury, a more relevant pre-clinical model of SCI. The growth factors were delivered for the first 7 days to the injury site by osmotic minipump. Locomotor behavior was monitored at 1-28 days after injury using the Basso, Beattie and Bresnahan (BBB) score and at 30 days using automated gait analysis. Treated animals had BBB scores of 18; control animals scored 10. Treated animals had significantly reduced lesion cavities and reduced macroglia/macrophage activation around the injury site. We conclude that growth factor treatment preserved spinal cord tissues after contusion injury, thereby allowing functional recovery. This treatment has the potential to significantly reduce the severity of human spinal cord injuries.

Repair of the injured spinal cord by implantation of a synthetic degradable block copolymer in rat

The present study is designed to assess the properties of a new degradable PLA-b-PHEMA block copolymer hydrogel and its therapeutic effectiveness after implantation following a thoracic spinal cord hemisection on rats. Degradable characteristics and porous aspect of the scaffold are respectively analyzed by the evaluation of its mass loss and by electron microscopy. The biomaterial toxicity is measured through in vitro tests based on motoneuron survival and neurite growth on copolymer substrate. Functional measurements are assessed by the Basso, Beattie and Bresnahan (BBB) and the Dynamic Weight Bearing (DWB) tests during 8 weeks post-surgery. Histological analyses are achieved to evaluate the presence of blood vessels and axons, the density of the glial scar, the inflammatory reaction and the myelination at the lesion site and around it. The results indicate that the synthetic PLA-b-PHEMA block copolymer is a non-toxic and degradable biomaterial that provides support for regenerating axons and seems to limit scar tissue formation. Additionally, the implantation of the porous PLA-b-PHEMA scaffold enhances locomotor improvement. The observed functional recovery highlights the potential benefits of plain tissue engineering material, which can further be optimized by bioactive molecule functionalization or transplanted cell encapsulation.

Repair of Spinal Cord Injury (SCI) Using Bone Marrow Stromal Cell Transfected with Adenoviral Vector Expressing Glial derived Neurotropic Factor (GDNF) in a Rat SCI Model

Back ground Subsequent to spinal cord injury many pathological changes may occur that could lead to inappropriate environment for repair. The Most important of such changes is the death of neurons. Exogenous administration of growth factors that modulate neuronal survival, synaptic plasticity, and neurotransmission has been proposed as a potential therapeutic treatment for SCI. Among these growth factors, GDNF is a peptide with pleiotropic survival and growth-promoting effects on neurons. In addition, GDNF induces the growth of motor and sensory axons and inhibits neuronal apoptosis. Adult stem cells may provide new strategies to treat SCI. Among various types of candidate stem cells, bone marrow stromal cells (BMSC) are promising because they have shown potential to neuronal differentiation and repair in damaged spinal cord. In this study, we aimed to improve results of treatment using combination of BMSC and GDNF features. Methods: Rats were divided randomly into four groups of six. Spinal cord injury was then performed under general anesthesia using the weight dropping method. The BMSCs were injected on 3th day of post-spinal cord injury. Group one included rats receiving normal saline, group two received BMSC, group three received BMSC infected with adenoviruses encoding the beta-galactosidase gene, and group four received BMSC infected with adenoviruses encoding the GDNF gene. A Basso, Beattie and Bresnahan (BBB) score test was performed for a period of four weeks. Two weeks before the end of BBB, biotin dextran amine was injected intracerebrally followed by tissue staining at the end of the fourth week. Results: There was a significant difference in BBB scores between groups one and four (p<0.05). BBB scale improved to 12.8 points group one, while it was 8.6 in the control. There were no significant differences between other groups. There were significant differences in axon counting between group one and other groups (p<0.0001). Also, there were significant differences in axon counting between group four with groups two and three (p<0.0001). Conclusion: Combined use of these methods (GDNF expressing BMSCs) showed better results in comparison with BMSC alone. In this study the two methods were used simultaneously. The time of injection of BMSCs is very important and so we suggest that other injection times be tested. Key words: BMSC, GDNF, Gene Therapy, Spinal cord injury.

Effect of asiatic acid on oxidative stress after acute spinal cord injury in rats

Objective To observe the effect of asiatic aicd treatment on acute spinal cord injury in rats.Methods Forty-five SD rats were randomly divided into a sham-operation group,model control group and asiatic acid treatment group.Functional outcome measurements were evaluated by the Basso,Beattie and Bresnahan (BBB) score at 24,48 and 72 h.The sections were stained with hematoxylin and eosin for morphological and histopathological analyses.The reactive oxidative species and inflammatory factor were detected.Results The BBB score was significantly higher in the asiatic acid treatment group (6.70 ± 1.09 and 9.58 ±2.81) than in the model control group (3.05 ±0.98 and 4.55 ±0.65) at 48 h and 72 h (P ＜ 0.05).Compared to the model control,HE staining showed the histopathological performance was improved greatly in rat spinal cord in asiatic acid treatment group.At the three time points,tissue malondialdehyde (MDA) content in asiatic acid treatment group [(6.42 ± 0.15),(6.17 ± 0.25) and (5.48 ± 0.33) nmol/ml] was statistically significantly lower than in the model group [(7.55 ±0.37),(7.61 ± 0.24) and (6.59 ±0.22) nmol/ml].The superoxide dismutase (SOD) activity in the asiatic acid treatment group [(220.55 ±3.76),(231.44 ±4.88) and (235.98 ±5.26) U/mg] was higher than in the model group [(180.31 ±4.68,175.32 ±3.45 and 170.51 ±3.44) U/mg] at the three time points.After injury,tissue myeloperoxidase (MPO) and IL contents were increased,and showed a significant difference between the model control group and asiatic acid treatment group at the three time points.Conclusion The present study suggests that asiatic acid exerts neuroprotection by reducing oxidative stress. Key words: Asiatic acid; Spinal cord injury; Oxidative stress