Improvement of Parkinsonian behavior with co-grafts of Schwann cells and neural stem cells in the rat

BACKGROUND: Due to the lack of autograft transplant rejection, Schwann cells (SCs) can promote the proliferation of embryonic stem cells and the induction of dopaminergic neurons. Mesencephalic stem cells can be induced to produce dopaminergic neurons. The therapeutic effects of co-grafts of SCs and neural stem cells (NSCs) deserves further study and verification in Parkinsonian animal models.OBJECTIVE: To investigate the effects of Schwann cells and mesencephalic NSC co-grafts in Parkinsonian animal models on animal behavior and histology.DESIGN: Randomized controlled experiment.SETTING: Fudan University; Institute of Neuroscience, Chinese Academy of Sciences.MATERIALS: The following animals were obtained from the Experimental Animal Center, Shanghai Institute for Biological Science, Chinese Academy of Sciences: 5 Sprague-Dawley rats, embryonic day (E) 13–16; 16 neonatal Sprague-Dawley rats, postnatal day 1–3; and 18 adult SD rats of both genders. Animal experimentation met animal ethical approval.METHODS: The experiment was performed at the Department of Anatomy, Histology and Embryology, Shanghai Medical Center, Fudan University from September 2005 to January 2007. The mesencephalic NSCs were obtained from the brains of SD rats at E 13–16, and SCs were harvested from the sciatic nerves of neonatal rats at day 1–3. Hemiparkinsonian rats (n =18) were selected for transplantation after estimating rotational behavior in response to apomorphine and were randomly assigned to three groups: control group, NSC group, and co-graft group. There were 6 rats in each group. Either phosphate buffered saline (PBS), NSCs, or SCs plus NSCs were transplanted into the right neostriatum of Parkinsonian rats, respectively.MAIN OUTCOME MEASURES: ① Rotational behavior was induced by apomorphine (0.05 mg/kg, I.p.) 2, 4, 6, 8, and 10 weeks after transplantation, and the number of rotations were counted. ② Differentiation and survival of dopaminergic neurons in the right neostriatum were quantified by tyrosine hydroxylase immunohistochemistry 10 weeks after grafting.RESULTS: All 18 Parkinsonian rats were included in the final analysis,without any loss. ①Rotation behavior and turning: Compared with the control group, the percent of apomorphine-induced rotations were significantly decreased (P < 0.01) in both the NSC group and co-graft group. ②Differentiation and survival of dopaminergic neurons in each group: TH-immunoreactive neurons were detected in the striatum of both the NSC group and co-graft group 10 weeks after transplantation. The neuronal volume, size of the nucleus, and neuronal numbers were larger in the co-graft group compared to the NSC group (P < 0.05).CONCLUSION: SC and NSC co-grafts not only improve Parkinsonian behavior in rats, but also improve the survival of NSCs.     

经尾静脉注入大鼠骨髓间充质多能成体祖细胞向脑缺血灶微环境中的移行及效应

BACKGROUND： Multipotent adult progenitor cells （MAPCs） from the bone marrow have been shown to differentiate into neurons.
OBJECTIVE： To observe migration, survival, and neuronal-like differentiation of MAPCs by tail vein injection. DESIGN, TIME AND SETTING： Randomized, controlled experiment of neural tissue engineering was performed at the Laboratory for Cardio-Cerebrovascular Disease, Hospital of Integrated Traditional and Western Medicine, Tongji Medical College of Huazhong University of Science and Technology between September 2006 and August 2007. MATERIALS： Eighty Sprague Dawley rats, 3-6 months old, underwent cerebral ischemia/reperfusion by thread technique, and were randomly divided into model and MAPCs groups （n = 40）. METHODS： Mononuclear cells were harvested from bone marrow using the FicolI-Paque density gradient centrifugation method. After removing CD45 and glycophorin A-positive cells （GLYA＋） with immunomagnetic beads, CD45 GLYA adult progenitor cells were labeled with bromodeoxyuridine （5-bromo-2-deoxyuridine, BrdU）. A total of 1 mL cell suspension, containing 5 × 10^6 MAPCs, was injected into the MAPCs group through the tail vein. A total of 1 mL normal saline was injected into the model rats.
MAIN OUTCOME MEASURES： After 60 days, BrdU and neuron-specific enolase double-positive cells were observed using immunofluorescence. Cell morphology was observed under electron microscopy, and nerve growth factor mRNA was measured through RT-PCR. In addition, rat neurological functions were measured with behavioral tests.
RESULTS： Immunofluorescence revealed that MAPCs positive for BrdU and neuron specific enolase were found surrounding the ischemic focus in the MAPCs group. Microscopic observation suggested that MAPCs-derived neuronal-like cells connected with other nerve cells to form synapses. Compared with the model animals, the level of nerve growth factor mRNA was significantly upregulated in rats injected with MAPCs （P 〈 0.05）. In addition, rats in the MAPCs group performed better in behavioral tests than the model group on days 28 and 60 （P 〈 0.05）.
CONCLUSION： Transplanted MAPCs migrated to the ischemic region, survived, and differentiated into neuronal-like cells, resulting in stimulation of nerve growth factor mRNA and improved neurological function in ischemic rats.     

Soluble Nogo receptor 1 fusion protein protects neural progenitor cells in rats with ischemic stroke

Soluble Nogo66 receptor-Fc protein(sNgR-Fc)enhances axonal regeneration following central nervous system injury.However,the underlying mechanisms remain unclear.In this study,we investigated the effects of sNgR-Fc on the proliferation and differentiation of neural progenitor cells.The photothrombotic cortical injury model of ischemic stroke was produced in the parietal cortex of Sprague-Dawley rats.The rats with photothrombotic cortical injury were randomized to receive infusion of 400μg/kg sNgR-Fc(sNgR-Fc group)or an equal volume of phosphate-buffered saline(photothrombotic cortical injury group)into the lateral ventricle for 3 days.The effects of sNgR-Fc on the proliferation and differentiation of endogenous neural progenitor cells were examined using BrdU staining.Neurological function was evaluated with the Morris water maze test.To further examine the effects of sNgR-Fc treatment on neural progenitor cells,photothrombotic cortical injury was produced in another group of rats that received transplantation of neural progenitor cells from the hippocampus of embryonic Sprague-Dawley rats.The animals were then given an infusion of phosphate-buffered saline(neural progenitor cells group)or sNgR-Fc(sNgR-Fc+neural progenitor cells group)into the lateral ventricle for 3 days.sNgR-Fc enhanced the proliferation of cultured neural progenitor cells in vitro as well as that of endogenous neural progenitor cells in vivo,compared with phosphate-buffered saline,and it also induced the differentiation of neural progenitor cells into neurons.Compared with the photothrombotic cortical injury group,escape latency in the Morris water maze and neurological severity score were greatly reduced,and distance traveled in the target quadrant was considerably increased in the sNgR-Fc group,indicating a substantial improvement in neurological function.Furthermore,compared with phosphate-buffered saline infusion,sNgR-Fc infusion strikingly improved the survival and differentiation of grafted neural progenitor cells.Our findings show that sNgR-Fc regulates neural progenitor cell proliferation,migration and differentiation.Therefore,sNgR-Fc is a potential novel therapy for stroke and neurodegenerative diseases,The protocols were approved by the Committee on the Use of Live Animals in Teaching and Research of the University of Hong Kong(approval No.4560-17)in November,2015.     

心肌营养素1修饰的神经干细胞移植对癫(癎)持续状态大鼠海马损伤及苔藓纤维发芽的影响

Objective To observe the survival,migration and differentiation of grafted neural stem cells(NSCs)transfected with cardiotrophin-1(CT1)in hippocampus in status epilepticus(SE)rats,and investigate its effect on neuron loss and mossy fiber sprouting(MFS)in hippocampus of SE rats.Methods (1)Lithium-pilocarpine induced SE model rats were divided into 3 groups randomly:CT1-NSCs transplantation group(n=18);NScs transplantation group(n=18)and SE model group(n=18).Another 18 rats served as normal control group.Each group was further divided into 3 time points testing groups(n=6 at each point)corresponding to 1,4 and 8 weeks after transplantation respectively.(2)Under the confocal microscopy,the survival,migration and differentiation of the grafted cells were observed by immunofluorescenee.(3)Morphological changes and neuron loss in the hippocampal CA1 region were examined by Nissl staining.(4)MFS in hippocampal dentate gyrus in rats was obserred by Timm histochemistry.Results(1)At 4 and 8 weeks post-tmusplantation,the numbers of double-labeled NF-200 and EGFP pesitive cells in the CT1-NSCs group were significantly hisher than those in NSCs group.In the former group most of the grafted NSCs migrated away from the needle tract,but in the latter group,grafted ceHs remained at the transplantation site.(2)The numbers of neuron in the hippocampal CA1 region reduced gradually after SE.The numbers of neuron in the CA1 region in CT1-NSCs transplantation rats (68.85±11.49,60.89±12.17 and 51.51±13.34 in 1,4,8 weeks after transplantation respectivelv)were greater than that in NSCs transplantation rats(67.92±10.78,42.56±11.47 and 30.49±10.12).tvalue were 4.650 and 5.334 in 4 and 8 weeks after transplantation(P<0.05).(3)Aberrant MFS in the inner molecular layer of dentate gyrus was observed,and the scores of MFS gradually increased with timelapse.The scores of MFS in CT1-NSCs transplantation rats(0.77±0.04,2.48±0.89 and 2.39±0.82 in 1,4,8 weeks after transplantation respectively)were significant lower than that in NSCs transplantation rats (1.12±0.62,3.17±0.64 and 3.88±0.51,t=6.059,9.511 and 9.728,P<0.05).Conclusions CT1 could promote the survival,migration and differentiation of engrafted NSCs in hippocampud in SE rats.Engrafted NSCs transfected with CT1 have effect on repair of the injured hippocampus,and could inhibit hippocampus MFS in SE rats.     

心肌营养素1修饰的神经干细胞移植对癫(癎)持续状态大鼠海马损伤及苔藓纤维发芽的影响

Objective To observe the survival,migration and differentiation of grafted neural stem cells(NSCs)transfected with cardiotrophin-1(CT1)in hippocampus in status epilepticus(SE)rats,and investigate its effect on neuron loss and mossy fiber sprouting(MFS)in hippocampus of SE rats.Methods (1)Lithium-pilocarpine induced SE model rats were divided into 3 groups randomly:CT1-NSCs transplantation group(n=18);NScs transplantation group(n=18)and SE model group(n=18).Another 18 rats served as normal control group.Each group was further divided into 3 time points testing groups(n=6 at each point)corresponding to 1,4 and 8 weeks after transplantation respectively.(2)Under the confocal microscopy,the survival,migration and differentiation of the grafted cells were observed by immunofluorescenee.(3)Morphological changes and neuron loss in the hippocampal CA1 region were examined by Nissl staining.(4)MFS in hippocampal dentate gyrus in rats was obserred by Timm histochemistry.Results(1)At 4 and 8 weeks post-tmusplantation,the numbers of double-labeled NF-200 and EGFP pesitive cells in the CT1-NSCs group were significantly hisher than those in NSCs group.In the former group most of the grafted NSCs migrated away from the needle tract,but in the latter group,grafted ceHs remained at the transplantation site.(2)The numbers of neuron in the hippocampal CA1 region reduced gradually after SE.The numbers of neuron in the CA1 region in CT1-NSCs transplantation rats (68.85±11.49,60.89±12.17 and 51.51±13.34 in 1,4,8 weeks after transplantation respectivelv)were greater than that in NSCs transplantation rats(67.92±10.78,42.56±11.47 and 30.49±10.12).tvalue were 4.650 and 5.334 in 4 and 8 weeks after transplantation(P<0.05).(3)Aberrant MFS in the inner molecular layer of dentate gyrus was observed,and the scores of MFS gradually increased with timelapse.The scores of MFS in CT1-NSCs transplantation rats(0.77±0.04,2.48±0.89 and 2.39±0.82 in 1,4,8 weeks after transplantation respectively)were significant lower than that in NSCs transplantation rats (1.12±0.62,3.17±0.64 and 3.88±0.51,t=6.059,9.511 and 9.728,P<0.05).Conclusions CT1 could promote the survival,migration and differentiation of engrafted NSCs in hippocampud in SE rats.Engrafted NSCs transfected with CT1 have effect on repair of the injured hippocampus,and could inhibit hippocampus MFS in SE rats.     

心肌营养素1修饰的神经干细胞移植对癫(癎)持续状态大鼠海马损伤及苔藓纤维发芽的影响

Objective To observe the survival,migration and differentiation of grafted neural stem cells(NSCs)transfected with cardiotrophin-1(CT1)in hippocampus in status epilepticus(SE)rats,and investigate its effect on neuron loss and mossy fiber sprouting(MFS)in hippocampus of SE rats.Methods (1)Lithium-pilocarpine induced SE model rats were divided into 3 groups randomly:CT1-NSCs transplantation group(n=18);NScs transplantation group(n=18)and SE model group(n=18).Another 18 rats served as normal control group.Each group was further divided into 3 time points testing groups(n=6 at each point)corresponding to 1,4 and 8 weeks after transplantation respectively.(2)Under the confocal microscopy,the survival,migration and differentiation of the grafted cells were observed by immunofluorescenee.(3)Morphological changes and neuron loss in the hippocampal CA1 region were examined by Nissl staining.(4)MFS in hippocampal dentate gyrus in rats was obserred by Timm histochemistry.Results(1)At 4 and 8 weeks post-tmusplantation,the numbers of double-labeled NF-200 and EGFP pesitive cells in the CT1-NSCs group were significantly hisher than those in NSCs group.In the former group most of the grafted NSCs migrated away from the needle tract,but in the latter group,grafted ceHs remained at the transplantation site.(2)The numbers of neuron in the hippocampal CA1 region reduced gradually after SE.The numbers of neuron in the CA1 region in CT1-NSCs transplantation rats (68.85±11.49,60.89±12.17 and 51.51±13.34 in 1,4,8 weeks after transplantation respectivelv)were greater than that in NSCs transplantation rats(67.92±10.78,42.56±11.47 and 30.49±10.12).tvalue were 4.650 and 5.334 in 4 and 8 weeks after transplantation(P<0.05).(3)Aberrant MFS in the inner molecular layer of dentate gyrus was observed,and the scores of MFS gradually increased with timelapse.The scores of MFS in CT1-NSCs transplantation rats(0.77±0.04,2.48±0.89 and 2.39±0.82 in 1,4,8 weeks after transplantation respectively)were significant lower than that in NSCs transplantation rats (1.12±0.62,3.17±0.64 and 3.88±0.51,t=6.059,9.511 and 9.728,P<0.05).Conclusions CT1 could promote the survival,migration and differentiation of engrafted NSCs in hippocampud in SE rats.Engrafted NSCs transfected with CT1 have effect on repair of the injured hippocampus,and could inhibit hippocampus MFS in SE rats.     

心肌营养素1修饰的神经干细胞移植对癫(癎)持续状态大鼠海马损伤及苔藓纤维发芽的影响

Objective To observe the survival,migration and differentiation of grafted neural stem cells(NSCs)transfected with cardiotrophin-1(CT1)in hippocampus in status epilepticus(SE)rats,and investigate its effect on neuron loss and mossy fiber sprouting(MFS)in hippocampus of SE rats.Methods (1)Lithium-pilocarpine induced SE model rats were divided into 3 groups randomly:CT1-NSCs transplantation group(n=18);NScs transplantation group(n=18)and SE model group(n=18).Another 18 rats served as normal control group.Each group was further divided into 3 time points testing groups(n=6 at each point)corresponding to 1,4 and 8 weeks after transplantation respectively.(2)Under the confocal microscopy,the survival,migration and differentiation of the grafted cells were observed by immunofluorescenee.(3)Morphological changes and neuron loss in the hippocampal CA1 region were examined by Nissl staining.(4)MFS in hippocampal dentate gyrus in rats was obserred by Timm histochemistry.Results(1)At 4 and 8 weeks post-tmusplantation,the numbers of double-labeled NF-200 and EGFP pesitive cells in the CT1-NSCs group were significantly hisher than those in NSCs group.In the former group most of the grafted NSCs migrated away from the needle tract,but in the latter group,grafted ceHs remained at the transplantation site.(2)The numbers of neuron in the hippocampal CA1 region reduced gradually after SE.The numbers of neuron in the CA1 region in CT1-NSCs transplantation rats (68.85±11.49,60.89±12.17 and 51.51±13.34 in 1,4,8 weeks after transplantation respectivelv)were greater than that in NSCs transplantation rats(67.92±10.78,42.56±11.47 and 30.49±10.12).tvalue were 4.650 and 5.334 in 4 and 8 weeks after transplantation(P<0.05).(3)Aberrant MFS in the inner molecular layer of dentate gyrus was observed,and the scores of MFS gradually increased with timelapse.The scores of MFS in CT1-NSCs transplantation rats(0.77±0.04,2.48±0.89 and 2.39±0.82 in 1,4,8 weeks after transplantation respectively)were significant lower than that in NSCs transplantation rats (1.12±0.62,3.17±0.64 and 3.88±0.51,t=6.059,9.511 and 9.728,P<0.05).Conclusions CT1 could promote the survival,migration and differentiation of engrafted NSCs in hippocampud in SE rats.Engrafted NSCs transfected with CT1 have effect on repair of the injured hippocampus,and could inhibit hippocampus MFS in SE rats.     

心肌营养素1修饰的神经干细胞移植对癫(癎)持续状态大鼠海马损伤及苔藓纤维发芽的影响

Objective To observe the survival,migration and differentiation of grafted neural stem cells(NSCs)transfected with cardiotrophin-1(CT1)in hippocampus in status epilepticus(SE)rats,and investigate its effect on neuron loss and mossy fiber sprouting(MFS)in hippocampus of SE rats.Methods (1)Lithium-pilocarpine induced SE model rats were divided into 3 groups randomly:CT1-NSCs transplantation group(n=18);NScs transplantation group(n=18)and SE model group(n=18).Another 18 rats served as normal control group.Each group was further divided into 3 time points testing groups(n=6 at each point)corresponding to 1,4 and 8 weeks after transplantation respectively.(2)Under the confocal microscopy,the survival,migration and differentiation of the grafted cells were observed by immunofluorescenee.(3)Morphological changes and neuron loss in the hippocampal CA1 region were examined by Nissl staining.(4)MFS in hippocampal dentate gyrus in rats was obserred by Timm histochemistry.Results(1)At 4 and 8 weeks post-tmusplantation,the numbers of double-labeled NF-200 and EGFP pesitive cells in the CT1-NSCs group were significantly hisher than those in NSCs group.In the former group most of the grafted NSCs migrated away from the needle tract,but in the latter group,grafted ceHs remained at the transplantation site.(2)The numbers of neuron in the hippocampal CA1 region reduced gradually after SE.The numbers of neuron in the CA1 region in CT1-NSCs transplantation rats (68.85±11.49,60.89±12.17 and 51.51±13.34 in 1,4,8 weeks after transplantation respectivelv)were greater than that in NSCs transplantation rats(67.92±10.78,42.56±11.47 and 30.49±10.12).tvalue were 4.650 and 5.334 in 4 and 8 weeks after transplantation(P<0.05).(3)Aberrant MFS in the inner molecular layer of dentate gyrus was observed,and the scores of MFS gradually increased with timelapse.The scores of MFS in CT1-NSCs transplantation rats(0.77±0.04,2.48±0.89 and 2.39±0.82 in 1,4,8 weeks after transplantation respectively)were significant lower than that in NSCs transplantation rats (1.12±0.62,3.17±0.64 and 3.88±0.51,t=6.059,9.511 and 9.728,P<0.05).Conclusions CT1 could promote the survival,migration and differentiation of engrafted NSCs in hippocampud in SE rats.Engrafted NSCs transfected with CT1 have effect on repair of the injured hippocampus,and could inhibit hippocampus MFS in SE rats.     

心肌营养素1修饰的神经干细胞移植对癫(癎)持续状态大鼠海马损伤及苔藓纤维发芽的影响

Objective To observe the survival,migration and differentiation of grafted neural stem cells(NSCs)transfected with cardiotrophin-1(CT1)in hippocampus in status epilepticus(SE)rats,and investigate its effect on neuron loss and mossy fiber sprouting(MFS)in hippocampus of SE rats.Methods (1)Lithium-pilocarpine induced SE model rats were divided into 3 groups randomly:CT1-NSCs transplantation group(n=18);NScs transplantation group(n=18)and SE model group(n=18).Another 18 rats served as normal control group.Each group was further divided into 3 time points testing groups(n=6 at each point)corresponding to 1,4 and 8 weeks after transplantation respectively.(2)Under the confocal microscopy,the survival,migration and differentiation of the grafted cells were observed by immunofluorescenee.(3)Morphological changes and neuron loss in the hippocampal CA1 region were examined by Nissl staining.(4)MFS in hippocampal dentate gyrus in rats was obserred by Timm histochemistry.Results(1)At 4 and 8 weeks post-tmusplantation,the numbers of double-labeled NF-200 and EGFP pesitive cells in the CT1-NSCs group were significantly hisher than those in NSCs group.In the former group most of the grafted NSCs migrated away from the needle tract,but in the latter group,grafted ceHs remained at the transplantation site.(2)The numbers of neuron in the hippocampal CA1 region reduced gradually after SE.The numbers of neuron in the CA1 region in CT1-NSCs transplantation rats (68.85±11.49,60.89±12.17 and 51.51±13.34 in 1,4,8 weeks after transplantation respectivelv)were greater than that in NSCs transplantation rats(67.92±10.78,42.56±11.47 and 30.49±10.12).tvalue were 4.650 and 5.334 in 4 and 8 weeks after transplantation(P<0.05).(3)Aberrant MFS in the inner molecular layer of dentate gyrus was observed,and the scores of MFS gradually increased with timelapse.The scores of MFS in CT1-NSCs transplantation rats(0.77±0.04,2.48±0.89 and 2.39±0.82 in 1,4,8 weeks after transplantation respectively)were significant lower than that in NSCs transplantation rats (1.12±0.62,3.17±0.64 and 3.88±0.51,t=6.059,9.511 and 9.728,P<0.05).Conclusions CT1 could promote the survival,migration and differentiation of engrafted NSCs in hippocampud in SE rats.Engrafted NSCs transfected with CT1 have effect on repair of the injured hippocampus,and could inhibit hippocampus MFS in SE rats.     

心肌营养素1修饰的神经干细胞移植对癫(癎)持续状态大鼠海马损伤及苔藓纤维发芽的影响

Objective To observe the survival,migration and differentiation of grafted neural stem cells(NSCs)transfected with cardiotrophin-1(CT1)in hippocampus in status epilepticus(SE)rats,and investigate its effect on neuron loss and mossy fiber sprouting(MFS)in hippocampus of SE rats.Methods (1)Lithium-pilocarpine induced SE model rats were divided into 3 groups randomly:CT1-NSCs transplantation group(n=18);NScs transplantation group(n=18)and SE model group(n=18).Another 18 rats served as normal control group.Each group was further divided into 3 time points testing groups(n=6 at each point)corresponding to 1,4 and 8 weeks after transplantation respectively.(2)Under the confocal microscopy,the survival,migration and differentiation of the grafted cells were observed by immunofluorescenee.(3)Morphological changes and neuron loss in the hippocampal CA1 region were examined by Nissl staining.(4)MFS in hippocampal dentate gyrus in rats was obserred by Timm histochemistry.Results(1)At 4 and 8 weeks post-tmusplantation,the numbers of double-labeled NF-200 and EGFP pesitive cells in the CT1-NSCs group were significantly hisher than those in NSCs group.In the former group most of the grafted NSCs migrated away from the needle tract,but in the latter group,grafted ceHs remained at the transplantation site.(2)The numbers of neuron in the hippocampal CA1 region reduced gradually after SE.The numbers of neuron in the CA1 region in CT1-NSCs transplantation rats (68.85±11.49,60.89±12.17 and 51.51±13.34 in 1,4,8 weeks after transplantation respectivelv)were greater than that in NSCs transplantation rats(67.92±10.78,42.56±11.47 and 30.49±10.12).tvalue were 4.650 and 5.334 in 4 and 8 weeks after transplantation(P<0.05).(3)Aberrant MFS in the inner molecular layer of dentate gyrus was observed,and the scores of MFS gradually increased with timelapse.The scores of MFS in CT1-NSCs transplantation rats(0.77±0.04,2.48±0.89 and 2.39±0.82 in 1,4,8 weeks after transplantation respectively)were significant lower than that in NSCs transplantation rats (1.12±0.62,3.17±0.64 and 3.88±0.51,t=6.059,9.511 and 9.728,P<0.05).Conclusions CT1 could promote the survival,migration and differentiation of engrafted NSCs in hippocampud in SE rats.Engrafted NSCs transfected with CT1 have effect on repair of the injured hippocampus,and could inhibit hippocampus MFS in SE rats.     

激肽释放酶促进实验性大鼠大脑皮质梗死后内源性神经干细胞的增殖、迁移和分化

目的 观察外源性激肽释放酶对大鼠皮质梗死后内源性神经再生的影响.方法 用易卒中型肾血管性高血压大鼠,随机分为局灶性大脑皮质梗死+激肽释放酶治疗组、大脑皮质梗死+溶剂对照组和假手术对照组,所有大鼠均腹腔注射5-溴脱氧尿嘧啶核苷(BrdU)用以标记新增殖细胞.分别在不同时间点行神经功能评分后处死大鼠,测脑梗死灶体积,并观察梗死侧侧脑室下区(SVZ)BrdU+、BrdU+/DCX+表达以及梗死灶周BrdU+、BrdU+/NeuN+表达.结果 与溶剂对照组及假手术对照组相比,激肽释放酶治疗促进了术后不同时间点梗死侧SVZ BrdU+、BrdU+/DCX+和梗死灶周BrdU+、BrdU+/NeuN+表达(术后7 d SVZ BrdU+分别为304.0±73.9、167.0±32.2和56.0±12.2,分别q=7.165、12.916、5.751,均P<0.05;SVZ BrdU+/DCX+分别为225.0±13.6、98.0±9.6和23.0±5.6,分别q=30.731、48.735和18.004,均P<0.01;梗死灶周BrdU+为490.0±82.0、308.0±51.5和49.0±9.5,分别q=7.920、19.184、11.264,均P<0.01;术后14 d梗死灶周BrdU+/NeuN+为21.0±3.4和13.0±2.6,t=4.568,P=0.001),并促进了神经功能恢复.结论 外源性激肽释放酶可促进大鼠皮质梗死后内源性神经干细胞活化,并改善神经功能.     

脑卒中后抑郁大鼠海马原位增殖的新生细胞存活和分化状态

目的 观察脑卒中后抑郁(post-stroke depression,PSD)大鼠海马原位增殖新生细胞的存活和分化.方法 采用左侧大脑中动脉阻塞(MCAO)联合慢性不可预见温和应激刺激(chronicmild stress,CMS)及孤养法建立PSD模型,将雄性SD大鼠分为假手术、脑卒中、CMS和PSD组.每组均为18只.采取免疫组织化学、荧光双标染色及共聚焦成像动态检测,比较各研究组大鼠左侧海马齿状回溴脱氧尿苷嘧啶(BrdU)及其与神经元特异性核蛋白(NeuN)或胶质纤维酸性蛋白(GFAP)共表达.结果 与脑卒中组(232.2±8.6、123.7±2.6、136.2±2.6)相比,PSD组大鼠左侧(伤侧)海马齿状回BrdU+细胞数在脑梗死后第21(156.2±2.5)、30(70.2±2.0)和45天(81.2±1.1)均明显减少(t=28.83、52.2、62.08,均P<0.01),但仍高于假手术组.与脑卒中组(79.3%±2.8%、87.7%±4.6%)相比,PSD组大鼠左侧(伤侧)海马齿状回BrdU+/NeuN+细胞比例在脑梗死后第30(69.0%±3.4%)和45天(78.3%±2.4%)均明显减少(t=5.871、4.403,均P<0.01).BrdU+/GFAP+细胞比例在脑梗死后30和45 d均明显增加(t=4.226、8.945,P<0.01).结论 PSD大鼠脑卒中后海马齿状回原位增殖的新生细胞存活降低,分化为神经元的比例下降,胶质细胞比例增加.     

TRPC1沉默对脑缺血大鼠神经干细胞迁移的影响

目的探讨瞬时受体电位通道1(TRPC1)沉默对脑缺血大鼠内源性神经干细胞增殖、迁移和分化的影响。方法 SD大鼠分为假手术组、脑缺血组、TRPC1沉默组(脑缺血+TRPC1沉默)和阴性对照组,以脑室内注射siRNA沉默TRPC1,以线栓法制作大鼠大脑中动脉脑缺血(MCAO)模型,脑缺血模型制作成功后,腹腔内注射Brdu标记内源性神经干细胞,分别于48 h、4 w后处死大鼠,行Brdu免疫组化染色、免疫荧光双标染色(Brdu/GFAP、Brdu/Neun)观察NSC的增殖、迁移和分化情况。结果脑缺血后48 h,脑缺血组和TRPC1沉默组SVZ区Brdu阳性表达均较假手术组明显增多(P0.01),但TRPC1沉默组Brdu阳性细胞数较缺血组低(P0.01)。脑缺血4 w后,缺血组与假手术组相比,皮质区具有更多的Brdu阳性细胞(P0.01),同样TRPC1沉默组Brdu阳性细胞数多于假手术组,但明显低于脑缺血组(P0.01);免疫荧光双标染色发现,脑缺血各组Brdu/GFAP、Brdu/Neun双阳性细胞的数量均比假手术组明显增高,但TRPC沉默组双阳性细胞显著少于脑缺血组和阴性对照组(P0.01)。结论 TRPC1沉默显著影响脑缺血大鼠SVZ区NSC的增殖、向脑缺血区迁移及向成熟细胞的分化。     

Temporal profile of stem cell division, migration, and differentiation from subventricular zone to olfactory bulb after transient forebrain ischemia in gerbils.

The stage of neurogenesis can be divided into three steps: proliferation, migration, and differentiation. To elucidate their detailed relations after ischemia, the three steps were comprehensively evaluated, in the subventricular zone (SVZ) through the rostral migratory stream (RMS) to the olfactory bulb (OB), in adult gerbil brain after 5 minutes of transient forebrain ischemia. Bromodeoxyuridine (BrdU), highly polysialylated neural cell adhesion molecule (PSA-NCAM), neuronal nuclear antigen (NeuN), and glial fibrillary acidic protein (GFAP) were used as markers for proliferation, migration, and differentiation, respectively. The number of BrdU-labeled cells that coexpressed PSA-NCAM and the size of PSA-NCAM-positive cell colony increased in the SVZ with a peak at 10 d after transient ischemia. In the RMS, the number of BrdU-labeled cells that coexpressed PSA-NCAM increased, with a delayed peak at 30 d, when the size of RMS itself became larger and the number of surrounding GFAP-positive cells increased. In the OB, BrdU + NeuN double positive cells were detected at 30 and 60 d. NeuN staining and terminal deoxynucleotidyl dUTP nick-end labeling staining showed no neuronal cell loss around the SVZ, and in the RMS and the OB after transient ischemia. These findings indicate that transient forebrain ischemia enhances neural stem cell proliferation in the SVZ without evident neuronal cell loss, and has potential neuronal precursor migration with activation of GFAP-positive cells through the RMS to the OB.     

Human embryonic neural stem cell transplantation increases subventricular zone cell proliferation and promotes peri‐infarct angiogenesis after focal cerebral ischemia

Neurogenesis and angiogenesis are two important processes that may contribute to the repair of brain injury after stroke. This study was designed to investigate whether transplantation of human embryonic neural stem cells (NSCs) into cortical peri‐infarction 24 h after ischemia effects cell proliferation in the subventricular zone (SVZ) and angiogenesis in the peri‐infarct zone. NSCs were prepared from embryonic human brains at 8 weeks gestation. Focal cerebral ischemia was induced by permanent occlusion of the middle cerebral artery of adult rats. Animals were randomly divided into two groups (n = 30, each) at 24 h after ischemia: NSC‐grafted and medium‐grafted groups. Toluidine blue staining and 5′‐bromo‐2′‐deoxyuridine (BrdU) or von Willebrand factor (vWF) immunohistochemistry were performed at 7, 14 and 28 days after transplantation. NSC transplantation increased the number of BrdU‐positive cells in the ischemic ipsilateral SVZ compared with the medium control at 7 days (P < 0.01). This difference in SVZ cell proliferation persisted at 14 days (P < 0.01), but was not significant at 28 days (P > 0.05). In addition, angiogenesis, as indicated by BrdU and vWF staining in cortical peri‐infarct regions, was augmented by 46% and 65% in NSC‐grafted rats versus medium‐grafted rats at 7 and 14 days, respectively (P < 0.05). However, this increase became non‐significant at 28 days (P > 0.05). Our results indicate that NSC transplantation enhances endogenous cell proliferation in the SVZ and promotes angiogenesis in the peri‐infarct zone, even if it is performed in the acute phase of ischemic injury.     

雌激素对大鼠脑缺血再灌注神经干细胞内源性激活的实验研究

目的探讨雌激素对脑缺血再灌注神经干细胞(neural stem cell,NSC)内源性激活的作用.方法将44只雄性大鼠随机分成假手术组、对照组和实验组.采用传统的线栓法制备大鼠大脑中动脉闭塞再灌注模型,实验组大鼠腹腔注射苯甲酸雌二醇,对照组腹腔注射生理盐水,通过免疫组织化学技术标记大鼠海马齿状回颗粒下层(subgranular zone,SGZ)、侧脑室室下层(subventricular zone,SVZ)以及梗死皮质周边区在缺血再灌注3、7、11、18 d的5-溴脱氧尿嘧啶核苷(bromodeoxyuridine,BrdU)阳性细胞,并采用HPIAS图像分析系统进行分析.结果正常成年大鼠脑组织SGZ和SVZ存在少量Brdu阳性细胞,对照组脑缺血再灌注3 d SGZ、SVZ和梗死皮质周边Brdu阳性细胞的数量开始增多,7 d达到高峰,11d后开始减少,18 d进一步下降.实验组与对照组相比,在各个时间点均能显著提高BrdU阳性细胞的数量(P＜0.01),而且增殖可以持续11d.结论脑缺血再灌注可激活脑内NSC的增殖,雌激素可以促进脑缺血再灌注多个区域NSC的增殖.     

Adult subventricular zone neuronal precursors continue to proliferate and migrate in the absence of the olfactory bulb.

Neurons continue to be born in the subventricular zone (SVZ) of the lateral ventricles of adult mice. These cells migrate as a network of chains through the SVZ and the rostral migratory stream (RMS) into the olfactory bulb (OB), where they differentiate into mature neurons. The OB is the only known target for these neuronal precursors. Here, we show that, after elimination of the OB, the SVZ and RMS persist and become dramatically larger. The proportion of dividing [bromodeoxyuridine (BrdU)-labeled] or dying (pyknotic or terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end-labeled) cells in the RMS was not significantly affected at 3 d or 3 weeks after bulbectomy (OBX). However, by 3 months after OBX, the percentage of BrdU-labeled cells in the RMS decreased by half and that of dying cells doubled. Surprisingly, the rostral migration of precursors continued along the RMS after OBX. This was demonstrated by focal microinjections of BrdU and grafts of SVZ cells carrying LacZ under the control of a neuron-specific promoter gene. Results indicate that the OB is not essential for proliferation and the directional migration of SVZ precursors.     

Neural stem cell proliferation and differentiation in a neonatal rat model of hypoxia/ischemia injury Acupuncture at Ren, Du, and urinary bladder meridians

BACKGROUND: Acupuncture improves the prognosis of neonatal hypoxic-ischemic encephalopathy (HIE). However, the cytological mechanism of acupuncture therapy remains poorly understood. In situ neural stem cell (NSC) proliferation theory proposes that the proliferation and differentiation of NSCs plays an important role in HIE treatment with acupuncture. OBJECTIVE: To investigate NSC proliferation and differentiation in the brain of a rat model of HIE during acupuncture at Ren, Du, and urinary bladder meridians. DESIGN, TIME AND SETTING: A randomized, controlled animal experiment was performed at the Central Laboratory of Shantou University Medical College from July 2005 to June 2009. MATERIALS: A 32~# 1-cun stainless steel acupuncture needle was purchased from Suzhou Acupuncture Supplies Co. Ltd., China. METHODS: A total of 90 Sprague-Dawley rats, aged 7 days, were randomly assigned to acupuncture, model and normal groups, with 30 animals in each group. Animals in acupuncture and model groups were subjected to left common carotid artery ligation followed by hypoxia for 2 hours to establish neonatal HIE models. Acupuncture group rats underwent acupuncture at Ren, Du, and urinary bladder meridians, once a day. MAIN OUTCOME MEASURES: The number, appearance, and distribution of bromodeoxyuridine (BrdU)-positive cells in the cerebral cortex and hippocampus of each group were compared. In addition, NSC differentiation in the occipital cortex and hippocampal dentate gyrus 40 days following model establishment was detected. RESULTS: BrdU-positive cells were dispersed in the cerebral cortex and hippocampus. The number of BrdU-positive cells in occipital cortex and hippocampal dentate gyrus of HIE rats remained unchanged following 3 and 7 days of acupuncture, but a significant increase was detected on days 14 and 28 (P < 0.01 or P < 0.05). At 40 days, immunofluorescence showed that a majority of BrdU-positive cells were co-lableled with the neuron marker, and neuron specific enolase, and a few were co-labeled with the astrocyte marker, and glial fibrillary acidic protein. CONCLUSION: Acupuncture at Ren, Du, and urinary bladder meridians promoted NSC proliferation in the occipital cortex and hippocampal dentate gyrus of HIE rats. Moreover, acupuncture-induced neoformative NSCs mostly differentiated into neurons.     

大鼠脑出血后内源性神经干细胞激活和增殖的实验研究

目的 观察大鼠脑出血模型内源性神经干细胞(NSCs)的激活、增殖情况及其对神经行为学表现的影响.方法 将72只SD大鼠按单双号分为脑出血组和假手术组.每组36只.脑出血组利用立体定向技术,将一定量的Ⅳ型胶原酶用微量进样器分别精确注入大鼠内囊诱导脑出血模型.假手术组注射等量体积的PBS.分别于术后1、7、14、21、28和35 d观察大鼠的神经功能表现.所有大鼠处死前1 d腹腔内注射5.溴脱氧尿嘧啶(BrdU),免疫组织化学方法动态检测大鼠脑内巢蛋白(nestin)和BrdU的表达.结果 假手术组大鼠脑内未见nestin和BrdU的表达.脑出血组血肿周围基底节和脑室下区可见nestin和BrdU的表达.脑出血后7 d后开始明显增加.14 d达高峰,21 d开始下降.28d恢复正常.脑出血后l～35d大鼠神经功能无明显恢复,与内源性NSCs的增殖程度无明显相关.结论 脑出血可导致内源性NSCs的激活和诱导其增殖:然而这种状态下NSCs的增殖能力和内源性NSCs对脑出血后神经功能缺损的修复均有限.     

重复经颅磁刺激对脑梗死大鼠梗死侧皮质内源性神经干细胞激活、增殖的影响

目的研究重复经颅磁刺激(rTMS)对脑梗死大鼠神经功能恢复及梗死侧皮质内源性神经干细胞激活、增殖的影响。方法将72只雄性SD大鼠随机分为模型组、假刺激组、rTMS组,每组24只,各组根据脑梗死后不同时间点再分为1、7、14、21 d四个亚组,每个亚组6只。采用线栓法制作左侧大脑中动脉闭塞脑梗死模型。rTMS组于动物清醒后当天即给予每天2次、每次30个脉冲的rTMS治疗(频率为0.5 Hz,场强为1.33 T);假刺激组模拟rTMS固定大鼠头部放置线圈但不给予脉冲磁刺激;模型组不给任何治疗。各组在规定的时间点应用改良的神经功能缺损评分(mNSS)进行神经功能评定,治疗结束前24 h腹腔注射5-溴脱氧尿嘧啶核苷(BrdU),应用免疫组织化学技术检测梗死侧皮质巢蛋白(nestin)及BrdU表达阳性细胞的数量。结果 rTMS组脑梗死后7、14、21 d mNSS评分明显低于假刺激组及模型组同时间点大鼠(P<0.05),假刺激组及模型组大鼠脑梗死后不同时间点mNSS评分差异不明显(P>0.05)。脑梗死后1d模型组、假刺激组和rTMS组梗死灶周围皮质均可见nestin及BrdU阳性细胞,7 d达高峰。和假刺激组及模型组同时间点相比,rTMS组7、14、21 d nestin及BrdU阳性细胞数量明显增多,两者比较差异明显(P<0.05)。结论 rTMS能促进脑梗死大鼠神经功能恢复,机制可能与rTMS治疗能促进脑梗死周围内源性神经干细胞的激活及增殖有关。