Urine-derived mesenchymal stem cells-derived exosomes enhances survival and proliferation of aging retinal ganglion cells.

OBJECTIVES: This study was designed to investigate to test the effect of exosomes from urine-derived mesenchymal stem cells (USCs) on the survival and viability of aging retinal ganglion cells (RGCs), and explored the preliminary related mechanisms. METHODS: Primary USCs were cultured and identified by immunofluorescence staining. Aging RGCs models were established by D-galactose treatment and identified by ß-Galactosidase staining. After treatment with USCs conditioned medium (with USCs removal), flow cytometry was performed to examine the apoptosis and cell cycle of RGCs. Cell viability of RGCs was detected by Cell-counting Kit 8 (CCK8) assay. Moreover, gene sequencing and bioinformatics analysis were applied to analyze the genetic variation after medium treatment in RGCs along with the biological functions of differentially expressed genes (DEGs). RESULTS: The number of apoptotic aging RGCs was significantly reduced in USCs medium-treated RGCs. Besides, USCs-derived exosomes exert significant promotion on the cell viability and proliferation of aging RGCs. Further, sequencing data analyzed and identified DEGs expressed in aging RGCs and aging RGCs treated with USCs conditioned medium. The sequencing outcomes demonstrated 117 upregulated genes and 186 downregulated genes in normal RGCs group vs aging RGCs group, 137 upregulated ones and 517 downregulated ones in aging RGCs group vs aging RGCs + USCs medium group. These DEGs involves in numerous positive molecular activities to promote the recovery of RGCs function. CONCLUSIONS: Collectively, the therapeutic potentials of USCs-derived exosomes include suppression on cell apoptosis, enhancement on cell viability and proliferation of aging RGCs. The underlying mechanism involves multiple genetic variation and changes of transduction signaling pathways.

Cellular Localization and Distribution of TGF-ß1, GDNF and PDGF-BB in the Adult Primate Central Nervous System.

The available data on the localization of transforming growth factor beta1 (TGF-ß1), glial cell line-derived neurotrophic factor (GDNF), and platelet-derived growth factor-BB (PDGF-BB) in the adult primate and human central nervous system (CNS) are limited and lack comprehensive and systematic information. This study aimed to investigate the cellular localization and distribution of TGF-ß1, GDNF, and PDGF-BB in the CNS of adult rhesus macaque (Macaca mulatta). Seven adult rhesus macaques were included in the study. The protein levels of TGF-ß1, PDGF-BB, and GDNF in the cerebral cortex, cerebellum, hippocampus, and spinal cord were analyzed by western blotting. The expression and location of TGF-ß1, PDGF-BB, and GDNF in the brain and spinal cord was examined by immunohistochemistry and immunofluorescence staining, respectively. The mRNA expression of TGF-ß1, PDGF-BB, and GDNF was detected by in situ hybridization. The molecular weight of TGF-ß1, PDGF-BB, and GDNF in the homogenate of spinal cord was 25 KDa, 30 KDa, and 34 KDa, respectively. Immunolabeling revealed GDNF was ubiquitously distributed in the cerebral cortex, hippocampal formation, basal nuclei, thalamus, hypothalamus, brainstem, cerebellum, and spinal cord. TGF-ß1 was least distributed and found only in the medulla oblongata and spinal cord, and PDGF-BB expression was also limited and present only in the brainstem and spinal cord. Besides, TGF-ß1, PDGF-BB, and GDNF were localized in the astrocytes and microglia of spinal cord and hippocampus, and their expression was mainly found in the cytoplasm and primary dendrites. The mRNA of TGF-ß1, PDGF-BB, and GDNF was localized to neuronal subpopulations in the spinal cord and cerebellum. These findings suggest that TGF-ß1, GDNF and PDGF-BB may be associated with neuronal survival, neural regeneration and functional recovery in the CNS of adult rhesus macaques, providing the potential insights into the development or refinement of therapies based on these factors.

AQP4 knockout promotes neurite outgrowth via upregulating GAP43 expression in infant rats with hypoxic-ischemic brain injury.

Neonatal hypoxic-ischemic encephalopathy (NHIE) induces severe cerebral damage and neurological dysfunction, with seldom effective therapy. Aquaporin-4 (AQP4) is involved in aggravating brain damage induced by NHIE. This study aimed to investigate the role of AQP4 underlying the pathogenesis of NHIE. Neonatal Sprague-Dawley rats were used to establish neonatal hypoxic-ischemic (HI) models, and the expression of AQP4 in the cortex, hippocampus, and lung tissues was detected by real-time quantitative polymerase chain reaction as well as Western blot. Primary cortical neurons were cultured for the oxygen-glucose deprivation (OGD) model, and siRNA was used to silence the expression of AQP4. Immunostaining of Tuj1 was performed to observe the axonal growth. CRISPER/Cas9 technology was used to knock out AQP4. The results demonstrated that AQP4 was upregulated in the cortex, hippocampus, and lung tissues in neonatal rats with HI and OGD neurons. Besides, silencing AQP4 promoted axonal growth of OGD neurons, and AQP4 knockout notably improved long-term neurobehavioral impairment. Furthermore, GAP43 was found closely correlated with AQP4 via GeneMANIA prediction. Significant downregulation of GAP43 was induced in OGD neurons, while AQP4 knockout markedly upregulated its expression in rats. This indicated that the depletion of AQP4 may enhance axonal regeneration and promote the long-term neurobehavioral recovery associated with the upregulation of GAP43 expression.

Establishment of Neurobehavioral Assessment System in Tree Shrew SCT Model.

Tree shrews, possessing higher developed motor function than rats, were more suitable to study neurological behavior after spinal cord injury (SCI). Here, we established a feasible behavioral assessment method to detect the degree of ethology recovery in tree shrew subjected to spinal cord transection (SCT). Tree shrews were divided into normal group, sham group, and SCT group. The tree shrew in sham group was subjected to laminectomy without SCI, while the tree shrews in the SCT group were subjected to a complete SCT in thoracic 10 (T10). A novel neurobehavior assessment scale was established, in which, the behavior index including slow advancement, fast advancement, standing, shaking head, voluntary jump, lateral movement, and tail status, was determined, respectively. Meanwhile, magnetic resonance imaging (MRI) was applied to observe the structure of the spinal cord, and diffusion tensor imaging (DTI)-based white matter mapping was used to show the fibers of the spinal cord. As a result, a marked decrease in locomotor function and consciousness was seen in tree shrews with SCT, and the detection of MRI showed the collapsing of nerve fibers after SCT is completely cut and there is corresponding to the behavior change. Together, the present study provided a novel and feasible method that can be used to assess the neurobehavior in SCT model from tree shrews, which may be useful to the SCI translational study in future preclinic trial.

A Novel Role of VEGFC in Cerebral Ischemia With Lung Injury.

Cerebral ischemia (CI) is a severe brain injury resulting in a variety of motor impairments combined with secondary injury in remote organs, especially the lung. This condition occurs due to insufficient blood supply to the brain during infancy. However, it has a molecular linkage that needs to be thoroughly covered. Here, we report on the role of vascular endothelial growth factor C (VEGFC) in lung injury induced by CI. The middle cerebral artery occlusion (MCAO) was depended to establish the animal model of CI. Rats were used and brain ischemia was confirmed through TTC staining. Serum was used for protein chip analysis to study the proteomic interaction. Immunohistochemistry analyses were used to quantify and locate the VEGFC in the lung and brain. The role of VEGFC was detected by siVEGFC technology in SY5Y, HUCEV, and A549 cell lines, under normal and oxygen glucose deprivation (OGD) conditions in vitro. As a result, the TTC staining demonstrated that the model of brain ischemia was successfully established, and MPO experiments reported that lung damage was induced in MCAO rats. VEGFC levels were up-regulated in serum. On the other hand, immunohistochemistry showed that VEGFC increased significantly in the cytoplasm of neurons, the endothelium of small trachea and the lung cells of CI animals. On a functional level, siVEGFC effectively inhibited the proliferation of SY5Y cells and decreased the viability of HUVEC cells in normal cell lines. But under OGD conditions, siVEGFC decreased the growth of HUVEC and increased the viability of A549 cells, while no effect was noticed on SYSY cells. Therefore, we confirmed the different role of VEGFC played in neurons and lung cells in cerebral ischemia-reperfusion injury. These findings may contribute to the understanding the molecular linkage of brain ischemia and lung injury, which therefore provides a new idea for the therapeutic approach to cerebral ischemia-reperfusion.

Protein Network Analysis of the Serum and Their Functional Implication in Patients Subjected to Traumatic Brain Injury.

Traumatic brain injury (TBI) often leads to severe neurobehavioral impairment, but the underlying molecular mechanism remains to be elucidated. Here, we collected the sera from 23 patients (aged from 19 to 81 years old, third day after TBI as TBI-third group) subjected to TBI from The First Hospital of Kunming City, and the sera from 22 healthy donors (aged from 18 to 81 years old and as control group). Then, three samples from TBI-third group and three samples from control group were subjected to the protein microarray detection, and bioinformatics analysis. Then, enzyme-linked immunosorbent assay (ELISA) was used to verify significantly altered protein levels. Results showed that, when compared with the control group, all significantly differentially expressed proteins [DEPs, P < 0.05, FDR < 0.05, fold change (FC) > 2] contained 172 molecules in the TBI-third group, in which 65 proteins were upregulated, while 107 proteins were downregulated. The biological processes of these DEPs, mostly happened in the extracellular region and the extracellular region parts, are mainly involved in the regulation of cellular process, signaling and signal transduction, cell communication, response to stimuli, the immune system process and multicellular organismal development. Moreover, the essential molecular functions of them are cytokine activity, growth factor activity and morphogen activity. Additionally, the most significant pathways are enriched in cytokine-cytokine receptor interaction and PI3K-Akt signaling pathways among downregulated proteins, and pathways in cancer and cytokine-cytokine receptor interaction among upregulated proteins. Of these, we focused on the NGF, NT-3, IGF-2, HGF, NPY, CRP, MMP-9, and ICAM-2 with a high number of interactors in Protein-Protein Interaction (PPI) Network indicated by bioinformatics report. Furthermore, using ELISA test, we confirmed that all increase in the levels of NGF, NT-3, IGF-2, HGF, NPY, CRP, MMP-9, and ICAM-2 in the serum from TBI patients. Together, we determined the screened protein expressional profiles in serum for TBI patients, in which the cross-network between inflammatory factors and growth factors may play a crucial role in TBI damage and repair. Our findings could contribute to indication for the diagnosis and treatment of TBI in future translational medicine and clinical practice.

Transplantation of Hematopoietic Stem Cells Promotes Functional Improvement Associated with NT-3-MEK-1 Activation in Spinal Cord-Transected Rats.

Transected spinal cord injury (SCT) is a devastating clinical disease that strongly affects a patient's daily life and remains a great challenge for clinicians. Stem-cell therapy has been proposed as a potential therapeutic modality for SCT. To investigate the effects of hematopoietic stem cells (HSCs) on the recovery of structure and function in SCT rats and to explore the mechanisms associated with recovery, 57 adult Sprague-Dawley rats were randomly divided into sham (n = 15), SCT (n = 24), and HSC transplantation groups (n = 15). HSCs (passage 3) labeled by Hoechst 33342, were transplanted intraspinally into the rostral, scar and caudal sites of the transected lesion at 14 days post-operation. Both in vitro and in vivo, HSCs exhibited a capacity for cell proliferation and differentiation. Following HSC transplantation, the animals' Basso, Beattie, and Bresnahan (BBB). locomotion scale scores increased significantly between weeks 4 and 24 post-SCT, which corresponded to an increased number of 5-hydroxytryptamine (5-HT) fibers and oligodendrocytes. The amount of astrogliosis indicated by immunohistochemical staining, was markedly decreased. Moreover, the decreased expression of neurotrophin- 3 (NT-3) and mitogen-activated protein kinase kinase-1 (MEK-1) after SCT was effectively restored by HSC transplantation. The data from the current study indicate that intraspinally administered HSCs in the chronic phase of SCT results in an improvement in neurological function. Further, the results indicate that intraspinally administered HSCs benefit the underlying mechanisms involved in the enhancement of 5-HT-positive fibers and oligogenesis, the suppression of excessive astrogliosis and the upregulation of NT3-regulated MEK-1 activation in the spinal cord. These crucial findings reveal not only the mechanism of cell therapy, but may also contribute to a novel therapeutic target for the treatment of spinal cord injury (SCI).

Bone marrow stromal cells promote neuroplasticity of cerebral ischemic rats via a phosphorylated CRMP2-mediated mechanism.

Collapsin response mediator protein 2 (CRMP2), an important protein involved in axonal growth and the maintenance of neuronal membrane integrity, has proved to be altered in nervous system diseases. This study was aimed to investigate the role of CRMP2 in bone marrow stromal cells (BMSCs) treating rats with cerebral ischemia. BMSCs were isolated from shaft of the femurs, tibiae, and humeri and were intra-carotid administrated immediately after middle cerebral artery occlusion (MCAO). Modified Neurological Severity Scores (mNSS) was conducted at 3, 7, 14dpo and the electrophysiologic evaluation was evaluated at 14dpo. Then all rats were sacrificed and brain tissues were harvested for RT-PCR, Western blot and Immunohistochemistry analysis. We found BMSCs treatment significantly improved the neurobehavioral performance impaired by ischemic brain injury, accompanied with the notably increasing levels of Synaptophysin (SYP) and Growth associated protein 43 (GAP43). We also found the protein level of phosphorylated CRMP2 (p-CRMP2) and phosphorylation-mediated protein including Glycogen synthase kinase 3 Beta (GSK3ß), Cyclin-dependent kinase 5 (CDK5) were dramatically downregulated in ischemic rats following BMSCs transplant. Furthermore, the GSK3ß-mediated factors including neurotrophic and signaling factors were all significantly upregulated in BMSCs-treated group. On the basis of these findings, we suggest that the neuroplasticity effect of BMSCs on cerebral ischemia may be associated with the phosphorylated modulation of CRMP2.

[Changes of the Expression of Brain Derived Neurotrophic Factors in Rats Trachea Induced by Acrolein Exposure].

OBJECTIVE: To investigate expressional changes of brain derived neurotrophic factor (BDNF) in the trachea of rats with acrolein inhalation. METHODS: Twenty two SD rats were divided into 2 groups: the rats in experimental group were subjected to acrolein inhalation for the induce of trachea inflammatory injury, while the rats with saline (NS) inhalation were as control. All the rats were sacrificed in 1,3,6 weeks after acrolein (n = 11 at each time point) or saline inhalation (n = 11 at each time point), the samples of trachea epithelium were harvested. The immunohistochemistry and in situ hybridization was performed to detect the location of BDNF protein and mRNA in trachea. The expression of BDNF mRNA in the trachea tissues were determined by RT-PCR. RESULTS: There are positive cells in epithelium of trachea for BDNF protein and mRNA, with cytoplasm staining. The expression of BDNF mRNA in the trachea was increased at 1 week after acrolein inhalation (P < 0.05, vs. control group), then decreased along with the time and reached to the same level as control group at 3 weeks, then last to 6 weeks (P > 0.05). CONCLUSION: The inflammatory injury in trachea induced by acrolein exposure could be associated with the increased expression of BDNF. BDNF may be one of the crucial inflammatory factors in the process of inflammatory reaction in trachea with acrolein stimulation.

Intrathecal injection of lentivirus-mediated glial cell line-derived neurotrophic factor RNA interference relieves bone cancer-induced pain in rats.

Bone cancer pain is a common symptom in cancer patients with bone metastases and the underlying mechanisms are largely unknown. The aim of this study is to explore the endogenous analgesic mechanisms to develop new therapeutic strategies for bone-cancer induced pain (BCIP) as a result of metastases. MRMT-1 tumor cells were injected into bilateral tibia of rats and X-rays showed that the area suffered from bone destruction, accompanied by an increase in osteoclast numbers. In addition, rats with bone cancer showed apparent mechanical and thermal hyperalgesia at day 28 after intratibial MRMT-1 inoculation. However, intrathecal injection of morphine or lentivirus-mediated glial cell line-derived neurotrophic factor RNAi (Lvs-siGDNF) significantly attenuated mechanical and thermal hyperalgesia, as shown by increases in paw withdrawal thresholds and tail-flick latencies, respectively. Furthermore, Lvs-siGDNF interference not only substantially downregulated GDNF protein levels, but also reduced substance P immunoreactivity and downregulated the ratio of pERK/ERK, where its activation is crucial for pain signaling, in the spinal dorsal horn of this model of bone-cancer induced pain. In this study, Lvs-siGDNF gene therapy appeared to be a beneficial method for the treatment of bone cancer pain. As the effect of Lvs-siGDNF to relieve pain was similar to morphine, but it is not a narcotic, the use of GDNF RNA interference may be considered as a new therapeutic strategy for the treatment of bone cancer pain in the future.

Combined Bone Mesenchymal Stem Cell and Olfactory Ensheathing Cell Transplantation Promotes Neural Repair Associated With CNTF Expression in Traumatic Brain-Injured Rats.

This study examined the role of bone mesenchymal stem cell (BMSC) and olfactory ensheathing cell (OEC) cografting on neural function and underlying molecular mechanisms in acute stage of traumatic brain injury (TBI) rats. Eighty Sprague-Dawley (SD) female rats were randomly divided into five groups (n = 16 per category): sham operated group (Sham), weight-drop-induced TBI group (TBI), BMSC transplantation group (BMSC), OEC transplantation group (OEC), and cotransplantation group (CO). Eight rats were randomly selected from each group for behavioral and morphological assessment. Another category (n = 8 rats) was employed in the genetic expression detection. BMSCs were isolated from GFP mice and identified by CD44 antibody. OECs were isolated from the SD rats, identified by P75 antibody and labeled by Hoechst 33342. They were then transplanted into the surrounding tissue of the epicenter of TBI rats. The result of neurological severity scores revealed that BMSC or OEC transplantation alone and BMSC and OEC cografting significantly ameliorated the neurological deficits of TBI rats. Quantitative immunohistochemical analysis showed that graft-recipient animals possessed dramatically more neurons and regenerated axons and smaller amounts of astrocytes than controls 14 days posttransplantation (p < 0.05). However, the expressional level of ciliary neurotrophic factor significantly decreased in the cografting group as determined by RT-PCR (p < 0.05), and the Janus kinase/signal transducer and activator of transcription pathway was significantly activated at 7 days after cell transplantation (p < 0.05). This study is the first to report the role of cotransplantation of BMSCs and OECs in the therapy of TBI and explore its potential molecular mechanisms, therefore providing the important morphological and molecular biological evidence for the clinical application of BMSC and/or OEC transplantation in TBI.

Effects of Governor Vessel electroacupuncture on the systematic expressions of NTFs in spinal cord transected rats.

This study evaluated the effects Governor Vessel electroacupuncture (GVEA) on the systematic regulation of neurotrophic factors (NTFs) in the spinal segments caudal (CSS) to the site of transection in rats subjected to spinal cord transection (SCT). Using RT-PCR, we amazingly found the gene expressions of NGF, IGF-1, FGF-2, CNTF, PDGF, TGF-ß1, TrkA, TrkB and TrkC were downregulated following GVEA treatment. However, the number of GAP-43 and Synaptophysin profiles in the CSS in the GVEA rats showed a significant increase, compared with non-EA animals, although both the 5-HT and corticospinal fibers have no statistical differences in the CSS. Simultaneously, there was significant recovery in hindlimb locomotor and sensory functions after GVEA treatment. Therefore, these findings challenge the past view that GVEA promotes functional restoration, which is linking to the up-regulation of NTFs in rats subjected to SCT. The present findings may give some novel indication on the mechanism of acupuncture for the treatment of SCI.

[Human umbilic mesenchymal stromal cells repairs diabetic foot in rats associated with VEGF expressional change].

UNLABELLED: OBJECTITVE: To explore the mechanism of human umbilic mesenchymal cells (HUMSCs) implantation for the treatment of diabetic foot in rats associate with vascular endothelia growth factor (VEGF) expression changes. METHODS: After diabetic foot model in rats were established by administration of streptozotozin (STZ) in intraperitoneal injection (2 weeks), ulceration in foot was induced by incision injury combined with swearing staphylococcus aureas. Then, HUMSCs were smeared on the ulceration of foot in diabetic rats. Ten days later, the densities of blood vessel and the level of VEGF expression were determined by using immunohistochemistry, RT-PCR and Western blot. RESULTS: HUMSC grafts reduced significantly the volume of ulceration in diabetic foot rats (P < 0.05). RT-PCR and Western blot showed that VEGF and its mRNA were significantly upregulated (P < 0.05). VEGF immunstaining was found in blood vessels and the densities of blood vessels in HUMSC group were increased significantly (P < 0.05). CONCLUSION: HUMSC implantation showed a positive role in promoting the recovery of the ulceration in foot with diabetic rats.

[Effect of human umbilici mesenchymal stromal cells implantation on the BDNF expression in diabetic foot rats].

UNLABELLED: OBJECTITVE: To investigate the effect of human umbilici mesenchymal cells (HUMSCs) implantation on the brain derived neurotrophic factor (BDNF) expression in diabetic foot rats. METHODS: SD rats were divided into three groups (n = 12): normal group, diadetic foot model group and HUMSC treatment group. Diabetic foot model in rats was established, then prepared HUMSC were implanted on the diabetic foot ulcers in rats, and control ones were administrated with saline only. The area of ulceration, sensory function, BDNF expression and its localization were determined by using morphology, physiological function measurement, RT-PCR and immunohistochemistry assay. RESULT: Siglificantly decreased area of ulceration in diabetic foot rats of HUMSC implantation group was observed. This was simultaneously companied with the sensory function improvement (P < 0.05). RT-PCR showed that BDNF mRNA expression was significantly up regulated (P < 0.05). BDNF immunstaining was located in epithelia tissue and the protein level of BDNF was markedly increased (P < 0.05). CONCLUSION: HUMSC implantation maybe an effective strategy on the treatment of ulceration in diabetic foot rats, and the possible mechanism may involve in BDNF expression.

[Implication of BDNF expression in transected spinal cord of rats].

OBJECTIVE: To explore the change of brain derived neurotrophic factor (BDNF) expression and its relationship with the neurological behavior after spinal cord transection (SCT) in rats. METHODS: 66 adult SD rats were assigned randomly to sham operation group and SCT group. Rats in SCT group were subjected T10-T11 spinal cord transection and allowed to survived 1 d, 3 d, 7 d, 14 d, 21 d and 28 d. BBB scores in hindlimbs were observed at 0, 7, 14, 21 and 28 days post operation (dpo). The BDNF expression was determined by using ELISA (28 d) and RT-PCR (each time point) techniques. The localization of BDNF and its mRNA at sham and 28 d after SCT was also observed by immunohistochemistry and in situ hybridization. RESULTS: After SCT, the motor function in hindlimbs disappear immediately. The BBB scores get a gradual recovery from 14 dpo to 28 dpo, when compared with that of former timepoint (P < 0.05). BDNF and its mRNA were located in cytoplasma and neurites. The level of BDNF mRNA (indicated by RT-PCR) was upregulated at 14 days after SCT than that in 1 and 3 dpo (P< 0. 05). The contents of BDNF in the injuried spinal cords at 28 dpo were increased than that in the sham operation group (P < 0.05). CONCLUSION: Neuroplasticity has occurred in rats subjected to SCT, and the mechanism may be involved in the increase of BDNF expression in the spinal cord with the time going.

[Changes of BDNF expression in neurons in traumatic brain injury rats].

OBJECTIVE: To investigate changes of brain derived neurotrophic factor (BDNF) expression in neurons in traumatic brain injury (TBI) rats. METHODS: Adult SD rats were divided into sham and operated group resulted from hammer fall contusion (30 cm high, 50 g weight). Thirteen rats in each group were used. Some of animals (n = 6 in each group) were used to perform immunohistochemistry and in situ hybridization, and the other (n = 7) was used for RT-PCR. After NSS assessment was determined at 1, 3, 8, 13 days, TBI rats were sacrificed, brain tissues were then harvested to measure BDNF level. Data were analyzed by using statistic method. RESULTS: A increased NSS scores (P < 0.05) was observed after TBI, which implied the significant neurobehavioral changes in rats. But a gradual decreasing NSS scores (P < 0.05) was also observed along with time prolonged. Severe neurological severity function was seen following TBI, and it presents a gradual improvement indicated by decreasing NSS scores, despite BDNF mRNA level in whole brain tissue did not present a significant change, the BDNF expression (indicated by optical density values analysis) in subcellular structure, known as neurons, exhibited a significant increase, when compared with that of sham group (P < 0.05). This could simultaneously accompany with the decrease in the number of neurons in TBI rats. CONCLUSION: TBI rats exhibit a neuroplasticity with the BDNF upregulation in neurons following injury.

[Effect of methylprednisolone on neurological behavior and the BDNF and NMDA receptor expression after traumatic spinal cord injury in rats].

OBJECTIVE: To study the effect of methylprednisolone on spinal cord injury rats' neural behavior and the expression of brain derived neurotrophic factor (BDNF) and N-methyl-D-aspartic acid (NMDA). METHODS: To establish rat model of spinal cord injury (SCI), the rats were randomly divided into sham operation group, SCI group and methylprednisolone group (n = 16 in each group). Eight rats were used for the behavioral assessment and BDNF measurement,the other eight animals was for the NMDA receptor test in each group. Within 8 h spinal cord contusion, methylprednisolone (50 mg/kg) was injected for methylprednisolone group, then after that the intramuscular injection of methylprednisolone was per day reduction in 10 mg/kg, till 5 days. By using immunohistochemical staining, the distribution of BDNF in the spinal cord and positive cell localization was observed and the number of positive cells were counted. The NMDA receptor affinity (Kd) and maximum binding amount (Bmax) were measured with [3H] MK-801 radioligand method, and the rat hind limb functional was also evaluated with BBB score analysis. RESULTS: Both the number of BDNF positive cells and the BBB score in methylprednisolone group was significant higher than that of SCI group; While increased receptor affinity (Kd) and decreased Bmax for NMDA receptor in methylprednisolone group was seen less than in SCI group (P < 0.05). CONCLUSION: Methylprednisolone can improve the function of rat hind limb, increase BDNF level and decreased NMDA receptor expression after spinal cord injury.

[Effect of gold belt on the BDNF and NMDA receptor expression and behaviour changes in rats following traumatic spinal cord injury].

OBJECTIVE: To study the effects of gold belt (GB), a Chinese Herbal, on behavioral changes and brain derived neutrophic factor (BDNF) expression and N-methyl-D-aspartic acid (NMDA) receptor level in rats subjected to spinal cord injury (SCI). METHODS: Adult male SD rats were randomly divided into three groups: (1) Sham group; (2) Spinal cord injury group (SCI group); (3) Spinal cord injury followed with gold belt treatment (gold belt 50 mg/(kg x d), intragastric gavage once daily for 7 days) group (GB group). The Basso, Beattie and Bresnahan (BBB) locomotor scale method was performed to evaluate the hindlimb motor function in the days 0, 3, 10 and 28. After 13 days, 8 rats in each group were treated with 1% sodium pentobarbital (30 mg/kg), myoloid tissue in T10 position was taken and stored in liquid nitrogen to detect NMDA receptor affinity and maximum binding amount (Bmax) with radioligand binding assay. After 28 days, rats were sacrificed and the spinal cords were harvested for immunohistochemistry to observe the localization of BDNF in the ventral and dorsal horn of the spinal cord. RESULTS: After spinal cord contusion, GB resulted in a significant increase on the number of BDNF positive neurons compared with traumatic group, and increased BBB score and decreased NMDA receptor were also found in GB group. Whereas decreased BDNF expression, NMDA receptor affininty (Kd) were observed in traumatic injury group. CONCLUSION: The gold belt treatment could effectively improve motor function, increase expression of BDNF, reduce the level of NMDA receptors in SCI rats. These data suggested that the gold belt played a role in the neuroplasticity after spinal cord injury.

[Regulation of BDNF expression in traumatic brain injury rats subjected single neucleated cell transplantation].

OBJECTIVE: To investigate the effect of single neucleated cells transplantation on the neurological function and brain derived neurotrophic factor (BDNF) expression in traumatic brain injury (TBI) rats. METHODS: TBI rats were established by hammer fall method from 30 cm height with 50 g weight. Single neucleated cells/ karyocytes from bone marrow were separated and prepared by ficoll medium, then transplanted into pericontusional tissues in the brain. Neurological function severity scores (NSS) were recorded at 1, 3, and 7 days post operation (dpo). The pericontusional tissues were harvested at 7 dpo to analyze the BDNF localization, expressional level. RESULTS: Single neucleated cell transplantation decreased NSS significantly, compared with TBI rats without cell implantation (P < 0.05). BDNF expression was upregulated and mainly found in neurons. CONCLUSION: The present study showed the single karyocytes transplantation could improve neurological function and the mechanism is possibly linked to the BDNF expression.