The effect of spinal cord injury on the expression of TGF-β and TNF-α in rat articular cartilage

Objective: To observe the expression of TGF-β and TNF-α in the spinal cord injured rat model and discuss the significance of the articular cartilage metabolism. Methods: 36 SD female rats were randomly divided into 2 groups: Rats models of spinal cord injury were implemented by Allen method. T10 laminectomy was performed in the control group. Both groups of rats were killed respectively in 1w, 3w and 6w. Hematoxylin-eosin stain was given to each slice in the model group and control group. Immunohistochemical stain was applied by using ABC method in the expression of TGF-β and TNF-α. Those expressed level were performed in image analysis and statistics process. Results: TGF-β and TNF-α were mainly distributed on the surface layer of the articular cartilage, with a weak expression in control group. The expression of TNF-α in the model group was more significant than that in the control group in the 1w, and still remained an evident difference with that in control group until the 6w(P ＜ 0.05). TGF-β expression of the model group had no remarkable difference with the control group in the lw (P ＞ 0.05) and prominently became stronger at 6w(P ＜ 0.05). Conclusion: The expression of TNF-o occurred early in the development of spinal cord injury, and the expression of TGF-β became stronger with the revival of spinal neural function. Both expressions were strengthened in articular cartilage in the 3rd week.     

Effect of expression of TGF-beta and TNF-alpha with Qidan granule treatment in rats by bleomycin-induced pulmonary fibrosis

Objective: To evaluate the therapeutic effects and mechanisms of Qidan granule in blemycinA5-induced pulmonary interstitial fibrosis (PIF)in rats. Methods: PIF models were established by blemycinA5-induced in rats. They were treated by Qidan granule and Hydrocortisone respectively. The pathological changes and collagen protein disposition were observed, and the expression of TGF-β, TNF-α proteins were measured by immunohistochemical technique . Results: The pulmonary alveolitis and fibrosis were alleviated remarkably in Qidan granule group compared with those in the model control group and hydrocortisone group (P <0. 01). The expression of TGF-β and TNF-α protein were higher in Qidan granule group than those in normal group , and were significantly less than those in the model control group and in hydrocortisone group (P < 0. 01). Conclusion: Qidan granule would ameliorate the pulmonary alveolitis and fibrosis. TGF-β and TNF-α might play an important role in the development of alveolitis and fibro     

Expression of IL-βα and TNF-α in MCMV Myocarditis and Its Role

In order to study the expression of IL-β and TNF-α in the myocardium of MCMV myocarditis and their role in the myocardial damages, 60 BALB/C mice of 4 weeks were randomly divided into two groups: 36 were injected intraperitoneally with MCMV and 24 served as control group. Immunohistochemistry was used to detect IL-β and TNF-α expression in the myocardium, and myocardial lesions were observed histopathologically. Histopathological study on the myocardium from infected mice revealed focal or diffuse lesions characterized by inflammatory cells and degeneration or necrosis of myocytes. The myocardial lesion score showed the degree of inflammatory cell infiltration was slight in MCMV myocarditis. The positive staining signals for IL-β and TNF-α proteins which mainly located in the infiltrating inflammatory cells and degenerative or necrotic myocytes were markedly detectable whereas there were no positive findings in the myocardium of control mice. IL-β and TNF-α was expressed in the myocardium of viral myocarditis murine model induced by MCMV. IL-β and TNF-α may play an important role in the pathogenesis of viral myocarditis.     

Expression of β-1,4-galactosyltransferase I in a surgically-induced rat model of knee osteoarthritic synovitis

Background There are few reports of a biological role for glycosyltransferases in the infiltration of osteoarthritic synovitis. The aim of this research was to investigate the expression and cellular location of β-1,4-galactosyltransferase Ⅰ （β-1,4-GaIT-Ⅰ） in a surgically-induced rat model of knee osteoarthritis （OA）, and explore the role of β-1,4-GalT-Ⅰ in the pathogenesis of OA.Methods Male Sprague-Dawley rats were randomly divided into three groups： OA group, sham group and normal group. The model of OA was established in the right knees of rats by anterior cruciate ligament transaction （ACLT） with partial medial meniscectomy. Fibroblast-like synoviocytes （FLSs） obtained from normal rat synovial tissue were cultured.The expression of β-1,4-GalT-Ⅰ mRNA in the synovial tissue, articular cartilage and FLSs treated with tumor necrosis factor-α （TNF-α） were assayed by real-time PCR. Western-blotting and immunohistochemisty were used to observe the expression of β-1,4-GalT-Ⅰ at the protein level. Double immunofluorescent staining was used to define the location of the β-1,4-GalT-Ⅰ with macrophage-like synoviocytes, FLSs, neutrophils, and TNF-α in the OA synovium. The alteration of TNF-α in FLSs which were treated with lipopolysaccharide （LPS） and β-1,4-GalT-Ⅰ-Ab were detected by enzyme-linked immunosorbent assay （ELISA）.Results The mRNA and protein expression of β-1,4-GalT-Ⅰ increased in synovial tissue of the OA group compared with the normal and sham groups at two and four weeks after the surgery, however, no significant difference appeared in the articular cartilage. Immunohistochemistry also indicated that the β-1,4-GalT-Ⅰ expression in OA synovium at four weeks after surgery increased sharply compared with the control group. β-1,4-GalT-Ⅰ co-localized with macrophage-like synoviocytes, FLSa, neutrophils and TNF-α in rat OA synovitis. Moreover, in vitro β-1,4-GalT-Ⅰ mRNA in FLSs was affected in a dose- and time-dependent manner in response to TNF-α stimulation. ELISA revealed that the expression of TNF-α was attenuated in FLSs in vitro when treated with anti β-1,4-GalT-Ⅰ antibody.Conclusion β-1,4-GalT-Ⅰ may play an important role in the inflammation process of rat OA synovial tissue which would provide the foundation for further researching into the concrete mechanism of β-1,4-GalT-Ⅰ in OA synovitis.     

Expression of Toll-like receptor 4 in neonatal cord blood mononuclear cells in patients with preeclampsia

The expression of Toll-like receptor 4 (TLR4) in neonatal cord blood mononuclear cells (MNCs) and serum TNF-α were investigated in order to explore the roles of TLR4 in the pathogenesis of preeclampsia.The study enrolled 27 patients suffering from preeclampsia (experimental group) and 21 normal pregnancy patients (control group).After MNCs were separated, the expression of TLR4 mRNA and protein was detected by using real-time quantitative PCR and Western blotting respectively, and the expression of TNF-α by using ELISA.The results showed the TLR4 mRNA level in cord blood MNCs (2-CT:0.07±0.17), TLR4 protein expression level (absorbance ratio:0.81%±0.15%) and TNF-α level (9.5±1.73 pg/mL) were all increased in experimental group as compared with control group with the differences being statistically significant (P<0.05).There was a positive correlation between the expression of TLR4 mRNA and TNF-α in both experimental group and control group (r=0.54 and 0.53, respectively, P<0.05).It was concluded that TLR4 expression in the experimental group of cord blood MNCs was increased and there was a positive correlation between the expression of TLR4 mRNA and TNF-α in both groups.TLR4-mediated release of inflammatory cytokines may be one of the important reasons leading to preeclampsia.     

Upregulation of TNF-α mRNA in hepatic fibrosis rats induced by dimethylnitrosamine

Objective：To observe the expression level of TNF-α mRNA in rats with hepatic fibrosis induced by dimethylnitrosamine （DMN） and to explore its relationship with collagen metabolism and its diagnostic value for hepatic fibrosis.Methods： Twenty-five male Wistar rats were randomly divided into normal control group （n=10） and model group （n=15）. Model rats were induced by DMN for 4 weeks and at final stage were executed. TNF-α mRNA were detected by RT-PCR and the inflammatory necrosis and collagen deposition in hepatic tissue were observed by HE stain and Sirius red stain. The liver functions were determined by automatic biochemical analytic device. The serum marks of liver fibrosis, such as HA, LN and Ⅳ-C were measured with ELISA and RIA. Results： In this study, the rat model of liver fibrosis induced by DMN was successfully constructed. RT-PCR reveals that TNF-α mRNA expression in control group is lower than that of model group. The liver functions of model group were impaired compared with those of the control group （P〈0.01）. Semi-quantitive analysis revealed that TNF-α/β-actin of normal rats was 0.39±0.12, while 0.93±0.05 of model rats. The concentration of HA （434.44±98.81 vs 252.9±26.59 ng/ml, P〈0.01）, LN （70.67±6.32 vs 37.90±5.97 ng/ml, P〈0.01） and Ⅳ-C （79.39±10.52 vs 21.40±4.17 ng/ml, P〈0.01） were significantly increased in the model group as well. Changes of the indexes were similar to the pathological damage of the liver. Conclusion： The results suggested that activation of TNF-α in liver tissues may be the common pathogenic mechanism of liver fibrosis. TNF-α may be a useful index for the diagnosis of hepatic fibrosis which worthies further investigation.     

Hyperbaric oxygen intervention on expression of hypoxia inducible factor-1α and vascular endothelial growth factor after spinal cord injury models in rats

【Abstract】Objective: To observe the change of expression of Hypoxia inducible factor-1α (HIF-1α) and Vascular endothelial growth factor (VEGF) after spinal cord injury at different time and to investigate the Neuroprotective mechanism of hyperbaric oxygen (HBO) on spinal cord injury (SCI) in rats. Methods: 160 adult Sprague-Dawley rats, weighing between 250g and 300g,were randomly assigned to 4 experimental groups (n=40 per group). SCI group: SCI was created with special NYU impactor of Allen’s by a 25gram-centimeter (GCM) impacting energy on T10 of the spinal cord. SCI HBO group: hyperbaric oxygen therapy after spinal cord injury model was established. Sham operation（SH）group: only laminectomy of T10 and no impact on the spinal cord was done. SH HBO group: hyperbaric oxygen therapy after sham operation. The hindlimb functional recovery was evaluated using Basso Beattie Bresnahan (BBB) score and the expression of HIF-1α and VEGF were observed with fluorescent quantitation PCR and Western-Blot method of six rats picked randomly from each group at different times of 1, 3, 7 and 14 days after operation. Result: Rats in the SCI group and SCI HBO group were paralyzed completely after operation with BBB 0-1 score. Rats in the SH group and SH HBO group could walk after sham operation with BBB 20-21 score. The BBB scores of rats in SCI HBO group was higher than that in SCI group at 7d and 14d time point obviously (P＜0.05);The expression of HIF-1α and VEGF in SCI group and SCI HBO group was higher than in SH group and SH HBO group at any time point obviously (P＜0.05);while the SCI HBO group presented the least expression of HIF-1α at 3d,7d and 14d time points (P＜0.05) and more expression of VEGF at 7d and 14d (P＜0.05) than that of the SCI group with significant difference. Conclusion: The experimental research showed HBO could improve the hind limb functional recovery after SCI in rats;The higher expression of HIF-1α and VEGF could promote repair of damaged spinal cord after SCI;The elevation and duration of the expression of VEGF and the expression of HIF-1α by HBO intervention maybe inversely related in the repair of damaged spinal cord and neuroprotective effect.     

Effect of Coiquhoumia Root on the Expression of Transforming Growth Factor-β in Mesangiai Proliferation Giomerulonephritis Model

Summary： To study the efficacy and the mechanism of Colquhoumia root （ Tripterygium hypoglaucure （Le,vL） Hutch） in the treatment of mesangial proliferation glomerulonephritis （MsPGN）, SD rats were injected with anti-thymoeyte serum （ATS） to make MsPGN model （anti-Thyl model）. The rats were then divided into 3 groups： normal control group, anti-Thyl model group and treatment group. Histopathologieal （HE, PAS）, immunohistoehemieal, RT-PCR technique and computer imaging analysis system were used to evaluate mesangial matrix production, the expression of TGF-β protein and mRNA in the tissues of kidney. Our result showed that proteinuria and the ratio of extraeellular matrix/glomerular capillaries area （ECM/CA） were increased significantly in model group. The expression of both TGF-β protein and mRNA in glomeruli was much higher in model group than in control group （P〈0.01）. After the treatment with Colquhoumia root, proteinuria, ECM/CA and the expression of both TGF-β1 protein and mRNA in glomeruli were significantly decreased in treatment group as compared with those in model group. It is concluded that Colquhoumia root is effective in reducing proteinuria and mesangial matrix proliferation in MsPGN and it may achieve these effects by inhibiting the expressions of TGF-β1 protein and mRNA of mesangial cells.     

The Therapeutic Effects of Rehmannia Oral Liquid for the Syndrome of Heat Accumulation with Yin Consumption in Esophagus Cancer Patients Undergoing Radiotherapy——A Report of 60 Cases

Objective: To observe the clinical therapeutic effects of Rehmannia Oral Liquid on the syndrome of heat accumulation with Yin consumption in intermediate or late esophagus cancer patients undergoing radiotherapy. Methods: The IFN-α, TNF-α, IL-1β and TGF-β1 levels in sera were determined by the method of ABC-WLISA before and after the treatment with Rehmannia Oral Liquid. At the same time, the observation was carried out on the patient's general condition, symptoms and signs, barium meal or CT examinations, and biopsy. Another 30 cases of esophagus cancer were treated singly with radiotherapy as the control group. Results: Rehmannia Oral Liquid could obviously improve the patient's general condition, and the symptoms and signs after radiotherapy. Based on the X-ray examination and biopsy, the short-term local control rate of the treatment group and the control group was 70.0% and 40.0% respectively, showing a significant difference (P<0.05). Before the treatment, the level of serum IFN-α of both cancer groups was lower and the levels of TNF-α, IL-1β and TGF-β1 were higher than that of normal group. After treatment, the level of IFN-α in both treatment group and control group increased significantly (P<0.01), and the treatment group improved more obviously than the control group (P<0.05). The level of TNF-α of both groups decreased significantly (P<0.01) after treatment, and the level of IL-1β decreased in treatment group and increased in control group without the significant difference as compared with that before treatment. The level of TGF-β1 was significantly increased in control group (P<0.05) and decreased in treatment group (P>0.05) after treatment. The difference between groups was significant (P<0.05). Conclusion: Rehmannia Oral Liquid can obviously reduce the radiotherapy reaction, improve the quality of life, and raise the therapeutic effects. The action mechanism of the Liquid may lie in balancing the cytokine network and regulating the disordered signal transmission.     

Influence of neurotrophin-3 on Bcl-2 and Bax expressions in spinal cord injury of rats

Objective： To study the protective mechanisms of neurotrophin-3 （NT-3） on the spinal cord injury. Methods：Totally 105 SD rats were randomly divided into 3 groups： control group, experimental group and sham operation group. Rats from the former 2 groups were inflicted to animal model of acute spinal cord injury according to Allen＇s （WD） by situating a thin plastic tube in the subarachnoid space below the injury level for perfusion. Rats in experimental group received 20 ul NT-3 （200 ng） from the tube at 0, 4, 8, 12, 24 h and 3, 7 d after injury, and those in control group got an equal volume of normal saline at the same time. The animals in sham operation group only received opening vertebral plate and tube was put in subarachnoid space. The rats were sacrificed at 4, 8, 12, 24 h and 3, 7, 14 d post injury （n=5）. The expression levels of Bcl-2 and Bax proteins in spinal cord of rats were detected by immunohistochemistry assay. Results： The level of Bax protein in control group significantly increased as compared with those in sham operation group, and the peak reached at 8 h after spinal cord injury. The Bcl-2 proteins were always weakly positive. The Bax proteins in NT-3 group significantly decreased but the Bcl-2 proteins obviously increased as compared with those in control group. Conclusion： NT-3 can protect spinal cord from injury in vivo. One of the mechanisms is that NT-3 can inhibit abnormal expression of Pax protein, and increase the expression of Bcl-2 protein, then inhibit apoptosis after spinal cord injury.     

Effect of Wumeiwan on Cytokines TNF-α, IL-6, IL-8, IL-10 and Expression of NF-κBp65 in Rats with Ulcerative Colitis

The effects of Wumeiwan （WMW） on TNF-α, IL-6, IL-8, IL-10 and NF-κBp65 in rats with ulcerative colitis （UC） were investigated, the curative effectiveness of WMW vs salicylazosulfapyridine （SASP） was compared, and the action mechanism was analyzed. Fifty-Six Sprague-Dawley （SD） rats were randomly divided into four groups （n=14 in each group, with equal ratio of male and female）： normal control group, model group, SASP group, and WMW group. Except normal control group, the rat UC models in the remaining three groups were established using the method of 2.4-dinitrochlorobenzene （DNCB） immunization and acetic acid local enema. The rats in model group, SASP group, and WMW group were treated with distilled water, SASP, and WMW respectively. The changes in the symptoms and signs were observed, and levels of IL-6, IL-8, TNF-α, IL-10 and the expression of NF-κBp65 in the colonic tissues were statistically analyzed. The results showed that the levels of IL-6, IL-8, and TNF-α were significantly increased （P〈0.01）, while those of IL-10 significantly reduced （P〈0.01） after establishment of rat UC models as compared with normal control group. The levels of IL-6, IL-8, and TNF-α were obviously lower, but the level of IL-10 was obviously higher in WMW and SASP groups than those in model group （P〈0.05）. The levels of IL-6, IL-8, and TNF-α were lower, while the level oflL-10 was higher in WMW group than in SASP group. NF-κBp65 was expressed negatively or weakly in normal colonic tissues. The positive expression rate of NF-κBp65 in WMW group and SASP group was obviously lower than in model group （P〈0.01）, and there was significant difference between WMW group and SASP group （P〈0.05）. It was concluded that rat UC model was established successfully. WMW could up-regulate the expression of IL-10, down-regulate the expression of TNF-α, IL-6, IL-8, and inhibit the NF-κBp65 activity to adjust immune function, indicating WMW had better curative effects on UC in rats.     

Effect of Electroacupuncture at Acupoints of the Governor Vessel on Aquaporin-4 in Rat with Experimental Spinal Cord Injury

This study is to investigate the effects of electroacupuncture at acupoints of the Governor Vessel（GV） on aquaporin-4 （AQP-4） expression and on functions of the hind limbs in the rat of spinal cord injury. The functions of the hind limbs were detected with BBB scale on the ld, 3d, 7d and 21d after the spinal cord injury, respectively, and AQP-4 expression in the spinal cord was determined with immunohistochemical method and analyzed quantitatively with image analyzer. The results indicated that on the ld after the spinal cord injury, increased AQP-4 expression can be seen significantly in both the gray matter and the white matter of the injured spinal cord, and it reached the peaks on the 3d after the spinal cord injury in both the electroacupuncture group and the spinal cord injury group. However, AQP-4 express was significantly decreased in the electroacupuncture group as compared with that in the control group on 7d, 14d and 21d （P〈0.05 or P〈0.01）. The decrease of AQP-4 expression almost went with the improvement of the neurological function, which suggested that electroacupuncture at the acupoints of the Governor Vessel can inhibit edema of the spinal cord to alleviate the secondary spinal cord injury by means of decreasing the AQP-4 expression after the spinal cord injury, so as to protect the residual normal spinal cord tissues and promote the rebuilding of nervous tissues.     

Regulation of estrogen receptors α and β in human breast carcinoma by exogenous leptin in nude mouse xenograft model

Background It is essential to clarify the interactions of hormones during the progression of human breast cancer. This study examined the effects of exogenous human leptin on estrogen receptor （ER） α and β in human breast tumor tissue in a nude mouse xenograft model. Methods We created nude mice xenografts of MCF-7 human breast cancer cells, and randomly divided them into an experimental group and a control group. The mice in experimental group were injected subcutaneously around tumors with human leptin, while the control group were injected with the same dose of normal saline. A real-time RT-PCR assay was developed to quantify the mRNA of ERα, β in the tumor tissues. Western blotting analyses were used to assess the relative quantities of the ERα , β proteins. Results Leptin-treated xenografted nude mice were successfully established. The amount of ERa mRNA was significantly higher in the leptin group than in the control group （P 〈0.01）, while the amount of ERβ mRNA was significantly lower in the leptin group than in the control group （P 〈0.01）. Western blotting analyses revealed that the ERa protein level was significantly higher in the leptin group than in the control group （P 〈0.01）, while the ERβ protein level was significantly lower in the leptin group than in the control group （P 〈0.01）. Conclusions Nude mouse xenograft model can be safely and serviceably treated with human leptin by subcutaneous injections around tumor. ERα, β were both targets of leptin in breast cancer. Leptin can up-regulate the expression of ERa and down-regulate the expression of the ERβ in human breast tumor.     

促红细胞生成素通过降低TSP-1和TGF-β表达对脊髓损伤保护作用的研究

Background Erythropoietin (EPO) functions as a tissue-protective cytokine in addition to its crucial hormonal role in red cell production and neuron protection. This study was designed to determine the erythropoietin neuron protection on experimental spinal cord trauma injury (SCI) rats by exploring the level of thrombospondin-1(TSP-1) and transforming growth factor-β (TGF-β) in the development of rats’ spinal cord injury (SCI) model. Methods Sixty Sprague–Dawley (SD) rats were divided into three groups at random (the sham operation control group, SCI group and erythropoietin treatment group). Using a weight-drop contusion SCI model in SCI group and erythropoietin treatment group, then rats were sacrificed at 24 h and 7d. BBB scores were checked as locomotor function. Pathological changes were also explored by H-E staining. The expression of TSP-1 and TGF-β were determined by immunohistochemistry staining analysis and Western Blot analysis respectively. Results Slighter locomotor dysfunction and more quickly recovered as their higher BBB scores were found in erythropoietin treatment group than that in SCI group (P < 0.01). Pathological observation also showed progressive disruption of the dorsal white and few neurons regeneration in SCI rats. TSP-1 and TGF-β expression increased at 24 h and 7 d after SCI in the injured segment. We observed TSP-1 and TGF-β expression was higher in the SCI group than in erythropoietin treatment group. Samples of spinal cord from the animals demonstrated a TSP-1 optical density of 112.2 ± 6.8 and TSP-1 positive cells were 5.7 ± 1.3 respectively. After injury, TSP-1 optical density and cell number increased to 287.2 ± 14.3 and 23.2 ± 2.6/mm2 at 24 h, 232.1 ± 13.2 and 15.2 ± 2.3/mm2 at 7 d. As to EPO treatment rats, the TSP-1 optical density and cell number decreased to 213.1 ± 11.6 and 11.9 ± 1.6/mm2 at 24 h, 189.9 ± 10.5 and 9.3 ± 1.5/mm2 at 7 d while comparing to the SCI rats (P < 0.01). TGF-β immunohistochemistry staining we couldn’t found it in sham-operated group rats. In SCI rats, optical density and positive neuron number were 291.4 ± 15.2 and 28.8 ± 4.9/mm2 at 24 h, 259.1 ± 12.3 and 23.9 ± 4.1/mm2 at 7 d, and also decreased in EPO treatment rats with 222.8 ± 11.9 and 13.7 ± 2.1/mm2 at 24 h, 196.5 ± 9.7 and 8.7 ± 2.2/mm2 at 7 d (P < 0.01). Conclusion Elevating expression of TSP-1 and TGF-β can be found in the injured segment of the spinal cord at 24h and 7d after injury, erythropoietin treatment effectively prevents pathological alterations from severer spinal cord injury via reduction the expression of TSP-1 and TGF-β.     

Effects of cold-damp and hot-damp environment on VEGF and IL-1 expression in joint cartilage cells in adjuvant arthritis in rats

OBJECTIVE:To study the effects of environmental factors on the degree of injury and expression of vascular endothelial growth factor(VEGF) and interleukin-1(IL-1) in cartilage cells of the joint in a rat model of adjuvant arthritis(AA).METHODS:SD rats aged 10 months were randomly divided into 4 groups that varied by temperature and humidity housing conditions and induction of AA:a control group,a model group,a cold-damp group,and a hot-damp group.All groups except the control group were induced with AA.After 4 w,VEGF and IL-1 expression in cartilage cells of ankle joints of hind limbs were observed.RESULTS:Mean area,optical density,and numbers of VEGF-and IL-1-positive cells in the model group,the cold-damp group,and the hot-damp group were significantly higher than that of the control group(all P<0.05).Optical density and positive cell numbers in the cold-damp group and the hot-damp group were significantly higher than that of the model group(all P<0.05).Optical density and positive cell numbers in the hot-damp group were significantly higher than that of the cold-damp group.Bone in the hot-damp and cold-damp groups was severely injured.CONCLUSION:Environmental factors such as high humidity combined with either high or low temperature increase the severity of damage and expression of VEGF and IL-1 in cartilage cells of joints in rats induced with AA.     

Human neural stem cells promote corticospinal axons regeneration and synapse reformation in injured spinal cord of rats

Background Axonal regeneration in lesioned mammalian central nervous system is abortive, and this causes permanent disabilities in individuals with spinal cord injuries. This paper studied the action of neural stem cell （NSC） in promoting corticospinal axons regeneration and synapse reformation in rats with injured spinal cord. Methods NSCs were isolated from the cortical tissue of spontaneous aborted human fetuses in accordance with the ethical request. The cells were discarded from the NSC culture to acquire NSC-conditioned medium. Sixty adult Wistar rats were randomly divided into four groups （n=15 in each）： NSC graft, NSC medium, graft control and medium control groups. Microsurgical transection of the spinal cord was performed in all the rats at the T11. The NSC graft group received stereotaxic injections of NSCs suspension into both the spinal cord stumps immediately after transection; graft control group received DMEM injection. In NSC medium group, NSC-conditioned medium was administered into the spinal cord every week; NSC culture medium was administered to the medium control group. Hindlimb motor function was assessed using the BBB Locomotor Rating Scale. Regeneration of biotin dextran amine （BDA） labeled corticospinal tract was assessed. Differentiation of NSCs and the expression of synaptophysin at the distal end of the injured spinal cord were observed under a confocal microscope. Group comparisons of behavioral data were analyzed with ANOVA. Results NSCs transplantation resulted in extensive growth of corticospinal axons and locomotor recovery in adult rats after complete spinal cord transection, the mean BBB scores reached 12.5 in NSC graft group and 2.5 in graft control group （P〈 0.05）. There was also significant difference in BBB score between the NSC medium （11.7） and medium control groups （3.7, P〈 0.05）. BDA traces regenerated fibers sprouted across the lesion site and entered the caudal part of the spinal cord. Synaptophysin expression colocalized with BDA positive axons and neurons distal to the injury site. Transplanted cells were found to migrate into the lesion, but not scatter along the route of axon grows. The cells differentiated into astrocytes or oligodendrocytes, but not into the neurons after transplantation. Furthermore, NSC medium administration did not limit the degree of axon sprouting and functional recovery of the injured rats compared to the NSC graft group. Conclusions Human embryonic neural stem cells can promote functional corticospinal axons regeneration and synapse reformation in the injured spinal cord of rats. The action is mainly through the nutritional effect of the stem cells on the spinal cord.     

Protection of erythropoietin on experimental spinal cord injury by reducing the expression of thrombospondin-1 and transforming growth factor-β

Background Erythropoietin （EPO） functions as a tissue-protective cytokine in addition to its crucial hormonal role in red cell production and neuron protection. This study aimed to determine the neuron protective effect of erythropoietin on experimental rats enduring spinal cord injury （SCI） by assessing thrombospondin-1 （TSP-1） level and transforming growth factor-β （TGF-β） in the development of a rat model of SCI. Methods Sixty Sprague-Dawley rats were randomly assigned to three groups： sham operation control group, SCI group and EPO treatment group. By using a weight-drop contusion SCI model, the rats in the SCI group and EPO treatment group were sacrificed at 24 hours and 7 days subsequently. The Basso, Beattie, and Bresnahan （BBB） scores were examined for locomotor function. Pathological changes were observed after HE staining. The expressions of thrombospondin-2 （TSP-1） and TGF-β were determined by immunohistochemical staining and Western blotting. Results Slighter locomotor dysfunction was discovered and it was recovered abruptly as higher BBB scores were found in the EPO treatment group than in the SCI group （P 〈0.01）. Pathologically, progressive disruption of the dorsal white matter and regeneration of a few neurons were also observed in SCI rats. TSP-1 and TGF-β expression increased at 24 hours and 7 days after SCI in the injured segment, and it was higher in the SCI group than in the EPO treatment group. Spinal cord samples from the animals demonstrated a TSP-1 optical density of 112.2±6.8 and TSP-1 positive cells of 5.7±1.3 respectively. After injury, the TSP-1 optical density and cell number increased to 287.2±14.3/mm^2 and 23.2±2.6/mm^2 at 24 hours and to 232.1±13.2/mm^2 and 15.2±2.3/mm^2 at 7 days respectively. When EPO treated rats compared with the SCI rats, the TSP-1 optical density and cell number decreased to 213.1 ±11.6/mm^2 and 11.9±1.6/mm^2 at 24 hours and to 189.9±10.5/mm^2 and 9.3±1.5/mm^2 at 7 days, respectively （P 〈0.01）. In the SCI rats, the TGF-β optical density and positive neuron number were 291.4±15.2/mm^2 and 28.8±4.9/mm^2 at 24 hours and 259.1±12.3/mm^2 and 23.9±4.1/mm^2 at 7 days respectively. They decreased in the EPO treated rats to 222.8±11.9/mm^2 and 13.7±2.1/mm^2 at 24 hours and to 196.5±9.7/mm^2 and 8.7±2.2/mm^2 at 7 days （P 〈0.01）. Conclusions Increased expression of TSP-1 and TGF-β can be found in the injured segment of the spinal cord at 24 hours and 7 days after injury. EPO treatment can effectively prevent pathological alterations from severe spinal cord injury by reduced expression of TSP-1 and TGF-β.