Neural Growth Factor Stimulates Proliferation of Spinal Cord Derived-Neural Precursor/Stem Cells

OBJECTIVE: Recently, regenerative therapies have been used in clinical trials (heart, cartilage, skeletal). We don't make use of these treatments to spinal cord injury (SCI) patients yet, but regenerative therapies are rising interest in recent study about SCI. Neural precursor/stem cell (NPSC) proliferation is a significant event in functional recovery of the central nervous system (CNS). However, brain NPSCs and spinal cord NPSCs (SC-NPSCs) have many differences including gene expression and proliferation. The purpose of this study was to investigate the influence of neural growth factor (NGF) on the proliferation of SC-NPSCs. METHODS: NPSCs (2×10⁴) were suspended in 100 µL of neurobasal medium containing NGF-7S (Sigma-Aldrich) and cultured in a 96-well plate for 12 days. NPSC proliferation was analyzed five times for either concentration of NGF (0.02 and 2 ng/mL). Sixteen rats after SCI were randomly allocated into two groups. In group 1 (SCI-vehicle group, n=8), animals received 1.0 mL of the saline vehicle solution. In group 2 (SCI-NGF group, n=8), the animals received single doses of NGF (Sigma-Aldrich). A dose of 0.02 ng/mL of NGF or normal saline as a vehicle control was intra-thecally injected daily at 24 hour intervals for 7 days. For Immunohistochemistry analysis, rats were sacrificed after one week and the spinal cords were obtained. RESULTS: The elevation of cell proliferation with 0.02 ng/mL NGF was significant (p<0.05) but was not significant for 2 ng/mL NGF. The optical density was increased in the NGF 0.02 ng/mL group compared to the control group and NGF 2 ng/mL groups. The density of nestin in the SCI-NGF group was significantly increased over the SCI-vehicle group (p<0.05). High power microscopy revealed that the density of nestin in the SCI-NGF group was significantly increased over the SCI-vehicle group. CONCLUSION: SC-NPSC proliferation is an important pathway in the functional recovery of SCI. NGF enhances SC-NPSC proliferation in vitro and in vivo. NGF may be a useful option for treatment of SCI patients pending further studies to verify the clinical applicability.

Transplantation of NGF modified umbilical cord mesenchymal stem cells improves neurological deficits in rats subjected to brain trauma / 中华行为医学与脑科学杂志

Objective To investigate the effect of NGF gene modified umbilical cord mesenchymal stem cells (UCMSC) transplantation on neurological functional improvement in traumatic brain rats. Methods Cerebral contusion model in motor-sensory cortex in rats was established by a weight hammer falling method. UCMSC were culutred and transferred with NGF gene. After NGF expression and activity was identified,the NGF gene modified UCMSC were engrafted into injured brain. The neurological function was evaluated 2 weeks after brain injury. And the NGF immunostaining was also performed to explore the level of NGF expression. Results Severe neurological dysfunction( 10.50 ± 0.53 )occurred in rats after traumatic brain injury, while the UCMSC transplantaion led to a significant functional improvement( 7.75 ± 0. 71 )(P ＜ 0. 01 ). Moreover, the best functional improvement was found in rats receiveing UCMSC grafts modified with NGF gene (5.38 ± 0. 52 ) (P ＜ 0.01 ). Conclusion NGF gene modified UCMSC transplantation can improve neural behavior in rats with brain trauma.

Effect of Behavior Training on the Expression of Neural Growth Factor in the Dentate Gyrus in Rats with Left Lateral Hippocampal Infarction / 中国康复理论与实践

@#ObjectiveTo study the effect of behavior training on the expression of neural growth factor(NGF) in the dentate gyrus(DG) in rats with left lateral hippocampal infarction.Methods102 SD rats were randomized into fore-training,3 d,7 d,14 d,21 d,28 d,35 d,42 d,49 d training groups,fore-immobilization, 3 d、7 d,14 d,21 d,28 d,35 d,42 d,49 d immobilization groups and control group.Behavior training and immobilization were performed at 1st day after the infarction.Immunohistochemistry was used to detect the expression of NGF in the DG at different points of time.ResultsThe expression of NGF is certain in the normal DG of rats.The expression of NGF increased after infarction.However,the expression of NGF had obviously increased in fore-training groups compared with that in fore-immobilization groups.ConclusionBehavior training can accelerate the expression of NGF in the DG of rats with left hippocampal infarction.

Experimental study of rat bone marrow stromal cell proliferation and differentiation in vitro / 医学研究生学报

Objective:To study the conditions of in vitro proliferation and differentiation of rat bone marrow stromal cells(MSC) for its application in transplantation.Methods:MSC were obtained by flushing the shaft with DMEM using a sterile syringe,dissociated by density gradient centrifuge,and cultured in the medium containing DMEM and 10% fatal bovine serum(FBS).Then we added neural growth factors into the medium and observed their influence on MSC proliferation,differentiation and survival by phase contrast microscopy.Immunocytochemistry was used to identify cell types.Results:MSC cultured in medium containing DMEM/ 10% FBS/ neural growth factors proliferated quickly.The neuron-like cells appeared at 7-9 d with the expression of neurone specific enolase(NSE) at(52?9.2)% and glial fibrillary acidic protein(GFAP) at(15?7)%,and could survive more than 7 days;In contrast,cells induced by ?-mercaptoethanol(BME) died gradually after 24 hours.Conclusion:MSC can not only proliferate and differentiate into neuron-like cells effectively in the medium containing neural growth factors but also survive longer.