Hyperbaric oxygen therapy for the treatment of neonatal hypoxic-ischemic brain damage has been used clinically for many years, but its effectiveness remains controversial. In addition, the mechanism of this potential ...Hyperbaric oxygen therapy for the treatment of neonatal hypoxic-ischemic brain damage has been used clinically for many years, but its effectiveness remains controversial. In addition, the mechanism of this potential neuroprotective effect remains unclear. This study aimed to investigate the influence of hyperbaric oxygen on the proliferation of neural stem cells in the subventricular zone of neonatal Sprague-Dawley rats （7 days old） subjected to hypoxic-ischemic brain damage. Six hours after modeling, rats were treated with hyperbaric oxygen once daily for 7 days. Immunohistochemistry revealed that the number of 5-bromo-2＇-deoxyuridine positive and nestin positive cells in the subventricular zone of neonatal rats increased at day 3 after hypoxic-ischemic brain damage and peaked at day 5. After hyperbaric oxygen treatment, the number of 5-bromo-2＇- deoxyuddine positive and nestin positive cells began to increase at day 1, and was significantly higher than that in normal rats and model rats until day 21. Hematoxylin-eosin staining showed that hyperbaric oxygen treatment could attenuate pathological changes to brain tissue in neonatal rats, and reduce the number of degenerating and necrotic nerve cells. Our experimental findings indicate that hyperbaric oxygen treatment enhances the proliferation of neural stem cells in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage, and has therapeutic potential for promoting neurological recovery following brain injury.展开更多
Sensitive smell discrimination is based on structural plasticity of the olfactory bulb,which depends on migration and integration of newborn neurons from the subventricular zone.In this study,we examined the relations...Sensitive smell discrimination is based on structural plasticity of the olfactory bulb,which depends on migration and integration of newborn neurons from the subventricular zone.In this study,we examined the relationship between neural stem cell status in the subventricular zone and olfactory function in rats with diabetes mellitus.Streptozotocin was injected through the femoral vein to induce type 1 diabetes mellitus in Sprague-Dawley rats.Two months after injection,olfactory sensitivity was decreased in diabetic rats.Meanwhile,the number of Brd U-positive and Brd U＋/DCX＋double-labeled cells was lower in the subventricular zone of diabetic rats compared with agematched normal rats.Western blot results revealed downregulated expression of insulin receptorβ,phosphorylated glycogen synthase kinase 3β,and β-catenin in the subventricular zone of diabetic rats.Altogether,these results indicate that diabetes mellitus causes insulin deficiency,which negatively regulates glycogen synthase kinase 3β and enhances β-catenin degradation,with these changes inhibiting neural stem cell proliferation.Further,these signaling pathways affect proliferation and differentiation of neural stem cells in the subventricular zone.Dysfunction of subventricular zone neural stem cells causes a decline in olfactory bulb structural plasticity and impairs olfactory sensitivity in diabetic rats.展开更多
The subcellular localization of N-methyI-D-aspartic acid receptor subunit 1 in neural stem cells of the subventricular zone of adult rats was detected using electron microscopy, following immunohistochemistry and immu...The subcellular localization of N-methyI-D-aspartic acid receptor subunit 1 in neural stem cells of the subventricular zone of adult rats was detected using electron microscopy, following immunohistochemistry and immunogold-silver double staining. Results confirmed the presence of neural stem cells in the subventricular zone, which is a key neurogenic region in the central nervous system of adult mammals. The expression of N-methyI-D-aspartic acid receptor subunit 1 was higher than that of nestin and mainly distributed in the cell membrane, cytoplasm, rough endoplasmic reticulum and Golgi complex of neural stem cells.展开更多
Objective To analyze proliferation and differentiation of glial fibrillary acid protein(GFAP)-and nestin-positive(GFAP+/nestin+)cells isolated from the subventricular zone following fluid percussion brain injury to de...Objective To analyze proliferation and differentiation of glial fibrillary acid protein(GFAP)-and nestin-positive(GFAP+/nestin+)cells isolated from the subventricular zone following fluid percussion brain injury to determine whether GFAP+/nestin+ cells exhibit characteristics of neural stem cells.Methods Male Sprague-Dawley rats,aged 12 weeks and weighing 200-250 g,were randomly and evenly assigned to normal control group and model group.In the model group,a rat model of fluid percussion brain injury was established.Five days later,subventricular zone tissue was resected from each group and made into single cell suspension.After serum-free neural stem cell medium culture and subsequent serum-induced differentiation,cell type,proliferation and differentiation capacities were determined by immunofluorescence staining and flow cytometry.Results At 3-7 days after fluid percussion brain injury,nestin+/GFAP+ cells in the single cell suspension from the model group significantly outnumbered those from the normal control group(P<0.01).In the model group,an increased number of small neurospheres with smooth cell edge and bulged center formed after primary culture,and were clearly visible with the increase of culture time and medium replacement.After several passages,many clonal spheres were obtained,suggesting strong self-proliferatiing capacity.Neurospheres from the model group differentiated into astrocytes,neurons and oligodendrocytes.Conclusion GFAP+/nestin+ cells isolated from the adult rat subventricular zone after fluid percussion brain injury are thought to be neural stem cells because of their self-renewal and multi-differentiation capacities.展开更多
Background Functional electrical stimulation （FES） is known to promote the recovery of motor function in rats with ischemia and to upregulate the expression of growth factors which support brain neurogenesis.In this...Background Functional electrical stimulation （FES） is known to promote the recovery of motor function in rats with ischemia and to upregulate the expression of growth factors which support brain neurogenesis.In this study,we investigated whether postischemic FES could improve functional outcomes and modulate neurogenesis in the subventricular zone （SVZ） after focal cerebral ischemia.Methods Adult male Sprague-Dawley rats with permanent middle cerebral artery occlusion （MCAO） were randomly assigned to the control group,the placebo stimulation group,and the FES group.The rats in each group were further assigned to one of four therapeutic periods （1,3,7,or 14 days）.FES was delivered 48 hours after the MCAO procedure and divided into two 10-minute sessions on each day of treatment with a 10-minute rest between them.Two intraperitoneal injections of bromodeoxyuridine （BrdU） were given 4 hours apart every day beginning 48 hours after the MCAO.Neurogenesis was evaluated by immunofluorescence staining.Wnt-3 which is strongly implicated in the proliferation and differentiation of neural stem cells （NSCs） was investigated by Western blotting analysis.The data wera subjected to oneway analysis of variance （ANOVA）,followed by a Tukey/Kramer or Dunnett post hoc test.Results FES significantly increased the number of BrdU-positive cells and BrdU/glial flbrillary acidic protein doublepositive neural progenitor cells in the SVZ on days 7 and 14 of the treatment （P 〈0.05）.The number of BrdU/doublecortin （DCX） double-positive migrating neuroblast cells in the ipsilateral SVZ on day 14 of the FES treatment group （（522.77±33.32） cells/mm2） was significantly increased compared with the control group （（262.58±35.11） cells/mm2,P 〈0.05） and the placebo group （（266.17±47.98） cells/mm2,P 〈0.05）.However,only a few BrdU/neuron-specific nuclear protein-positive cells were observed by day 14 of the treatment.At day 7,Wnt-3 was upregulated in the ipsilateral SVZs of the rats receiving FES （（0.44±0.05）%） compared with those of the control group rats （（0.31±0.02）%,P 〈0.05） or the placebo group rats （（0.31±0.04）%,P 〈0.05）.At day 14,the corresponding values were （0.56±0.05）% in the FES group compared with those of the control group rats （（0.50±0.06）%,P 〈0.05） or the placebo group rats （（0.48±0.06）%,P 〈0.05）.Conclusion FES augments the proliferation,differentiation,and migration of NSCs and thus promotes neurogenesis,which may be related to the improvement of neurological outcomes.展开更多
BACKGROUND： The origin and classification of neural stem cells （NSCs） has been a subject of intense investigation for the past two decades. Efforts to categorize NSCs based on their location, function and expressio...BACKGROUND： The origin and classification of neural stem cells （NSCs） has been a subject of intense investigation for the past two decades. Efforts to categorize NSCs based on their location, function and expression have established that these cells are a heterogeneous pool in both the embryonic and adult brain. The discovery and additional characterization of adult NSCs has introduced the possibility of using these cells as a source for neuronal and glial replacement following injury or disease. To understand how one could manipulate NSC developmental programs for therapeutic use, additional work is needed to elucidate how NSCs are programmed and how signals during development are interpreted to determine cell fate. OBJECTIVE： This review describes the identification, classification and characterization of NSCs within the large neurogenic niche of the ventricular-subventricular zone （V-SVZ）. METHODS： A literature search was conducted using Pubmed including the keywords ＂ventricular-subventricular zone,＂ ＂neural stem cell,＂ ＂heterogeneity,＂ ＂identity＂ and/or ＂single cell＂ to find relevant manuscripts to include within the review. A special focus was placed on more recent findings using single-cell level analyses on neural stem cells within their niche（s）. RESULTS： This review discusses over 20 research articles detailing findings on V-SVZ NSC heterogeneity, over 25 articles describing fate determinants of NSCs, and focuses on 8 recent publications using distinct single-cell analyses of neural stem cells including fl0w cytometry and RNA-seq. Additionally, over 60 manuscripts highlighting the markers expressed on cells within the NSC lineage are included in a chart divided by cell type. CONCLUSIONS： Investigation of NSC heterogeneity and fate decisions is ongoing. Thus far, much research has been conducted in mice however, findings in human and other mammalian species are also discussed here. Implications of NSC heterogeneity established in the embryo for the properties of NSCs in the adult brain are explored, including how these cells may be redirected after injury or genetic manipulation.展开更多
It has long been asserted that failure to recover from central nervous system diseases is due to the system's intricate structure and the regenerative incapacity of adult neurons.Yet over recent decades,numerous s...It has long been asserted that failure to recover from central nervous system diseases is due to the system's intricate structure and the regenerative incapacity of adult neurons.Yet over recent decades,numerous studies have established that endogenous neurogenesis occurs in the adult central nervous system,including humans'.This has challenged the long-held scientific consensus that the number of adult neurons remains constant,and that new central nervous system neurons cannot be created or renewed.Herein,we present a comprehensive overview of the alterations and regulatory mechanisms of endogenous neurogenesis following central nervous system injury,and describe novel treatment strategies that to rget endogenous neurogenesis and newborn neurons in the treatment of central nervous system injury.Central nervous system injury frequently results in alterations of endogenous neurogenesis,encompassing the activation,proliferation,ectopic migration,diffe rentiation,and functional integration of endogenous neural stem cells.Because of the unfavorable local microenvironment,most activated neural stem cells diffe rentiate into glial cells rather than neurons.Consequently,the injury-induced endogenous neurogenesis response is inadequate for repairing impaired neural function.Scientists have attempted to enhance endogenous neurogenesis using various strategies,including using neurotrophic factors,bioactive materials,and cell reprogramming techniques.Used alone or in combination,these therapeutic strategies can promote targeted migration of neural stem cells to an injured area,ensure their survival and diffe rentiation into mature functional neurons,and facilitate their integration into the neural circuit.Thus can integration re plenish lost neurons after central nervous system injury,by improving the local microenvironment.By regulating each phase of endogenous neurogenesis,endogenous neural stem cells can be harnessed to promote effective regeneration of newborn neurons.This offers a novel approach for treating central nervous system injury.展开更多
基金supported by Guangdong Province Science Research Project,No.B30502
文摘Hyperbaric oxygen therapy for the treatment of neonatal hypoxic-ischemic brain damage has been used clinically for many years, but its effectiveness remains controversial. In addition, the mechanism of this potential neuroprotective effect remains unclear. This study aimed to investigate the influence of hyperbaric oxygen on the proliferation of neural stem cells in the subventricular zone of neonatal Sprague-Dawley rats （7 days old） subjected to hypoxic-ischemic brain damage. Six hours after modeling, rats were treated with hyperbaric oxygen once daily for 7 days. Immunohistochemistry revealed that the number of 5-bromo-2＇-deoxyuridine positive and nestin positive cells in the subventricular zone of neonatal rats increased at day 3 after hypoxic-ischemic brain damage and peaked at day 5. After hyperbaric oxygen treatment, the number of 5-bromo-2＇- deoxyuddine positive and nestin positive cells began to increase at day 1, and was significantly higher than that in normal rats and model rats until day 21. Hematoxylin-eosin staining showed that hyperbaric oxygen treatment could attenuate pathological changes to brain tissue in neonatal rats, and reduce the number of degenerating and necrotic nerve cells. Our experimental findings indicate that hyperbaric oxygen treatment enhances the proliferation of neural stem cells in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage, and has therapeutic potential for promoting neurological recovery following brain injury.
基金partly supported by the National Natural Science Foundation of China,No.81370448,81570725
文摘Sensitive smell discrimination is based on structural plasticity of the olfactory bulb,which depends on migration and integration of newborn neurons from the subventricular zone.In this study,we examined the relationship between neural stem cell status in the subventricular zone and olfactory function in rats with diabetes mellitus.Streptozotocin was injected through the femoral vein to induce type 1 diabetes mellitus in Sprague-Dawley rats.Two months after injection,olfactory sensitivity was decreased in diabetic rats.Meanwhile,the number of Brd U-positive and Brd U＋/DCX＋double-labeled cells was lower in the subventricular zone of diabetic rats compared with agematched normal rats.Western blot results revealed downregulated expression of insulin receptorβ,phosphorylated glycogen synthase kinase 3β,and β-catenin in the subventricular zone of diabetic rats.Altogether,these results indicate that diabetes mellitus causes insulin deficiency,which negatively regulates glycogen synthase kinase 3β and enhances β-catenin degradation,with these changes inhibiting neural stem cell proliferation.Further,these signaling pathways affect proliferation and differentiation of neural stem cells in the subventricular zone.Dysfunction of subventricular zone neural stem cells causes a decline in olfactory bulb structural plasticity and impairs olfactory sensitivity in diabetic rats.
基金the Natural Science Foundation of Universities in Jiangsu Province,No.07KJB310119the Natural Science Foundation of Jiangsu Province,No.BK2009087
文摘The subcellular localization of N-methyI-D-aspartic acid receptor subunit 1 in neural stem cells of the subventricular zone of adult rats was detected using electron microscopy, following immunohistochemistry and immunogold-silver double staining. Results confirmed the presence of neural stem cells in the subventricular zone, which is a key neurogenic region in the central nervous system of adult mammals. The expression of N-methyI-D-aspartic acid receptor subunit 1 was higher than that of nestin and mainly distributed in the cell membrane, cytoplasm, rough endoplasmic reticulum and Golgi complex of neural stem cells.
基金supported by the National Natural Science Foundation of China(No.30371442)New Teachers Foundation of Ministry of Education(No.20070698073)
文摘Objective To analyze proliferation and differentiation of glial fibrillary acid protein(GFAP)-and nestin-positive(GFAP+/nestin+)cells isolated from the subventricular zone following fluid percussion brain injury to determine whether GFAP+/nestin+ cells exhibit characteristics of neural stem cells.Methods Male Sprague-Dawley rats,aged 12 weeks and weighing 200-250 g,were randomly and evenly assigned to normal control group and model group.In the model group,a rat model of fluid percussion brain injury was established.Five days later,subventricular zone tissue was resected from each group and made into single cell suspension.After serum-free neural stem cell medium culture and subsequent serum-induced differentiation,cell type,proliferation and differentiation capacities were determined by immunofluorescence staining and flow cytometry.Results At 3-7 days after fluid percussion brain injury,nestin+/GFAP+ cells in the single cell suspension from the model group significantly outnumbered those from the normal control group(P<0.01).In the model group,an increased number of small neurospheres with smooth cell edge and bulged center formed after primary culture,and were clearly visible with the increase of culture time and medium replacement.After several passages,many clonal spheres were obtained,suggesting strong self-proliferatiing capacity.Neurospheres from the model group differentiated into astrocytes,neurons and oligodendrocytes.Conclusion GFAP+/nestin+ cells isolated from the adult rat subventricular zone after fluid percussion brain injury are thought to be neural stem cells because of their self-renewal and multi-differentiation capacities.
文摘Background Functional electrical stimulation （FES） is known to promote the recovery of motor function in rats with ischemia and to upregulate the expression of growth factors which support brain neurogenesis.In this study,we investigated whether postischemic FES could improve functional outcomes and modulate neurogenesis in the subventricular zone （SVZ） after focal cerebral ischemia.Methods Adult male Sprague-Dawley rats with permanent middle cerebral artery occlusion （MCAO） were randomly assigned to the control group,the placebo stimulation group,and the FES group.The rats in each group were further assigned to one of four therapeutic periods （1,3,7,or 14 days）.FES was delivered 48 hours after the MCAO procedure and divided into two 10-minute sessions on each day of treatment with a 10-minute rest between them.Two intraperitoneal injections of bromodeoxyuridine （BrdU） were given 4 hours apart every day beginning 48 hours after the MCAO.Neurogenesis was evaluated by immunofluorescence staining.Wnt-3 which is strongly implicated in the proliferation and differentiation of neural stem cells （NSCs） was investigated by Western blotting analysis.The data wera subjected to oneway analysis of variance （ANOVA）,followed by a Tukey/Kramer or Dunnett post hoc test.Results FES significantly increased the number of BrdU-positive cells and BrdU/glial flbrillary acidic protein doublepositive neural progenitor cells in the SVZ on days 7 and 14 of the treatment （P 〈0.05）.The number of BrdU/doublecortin （DCX） double-positive migrating neuroblast cells in the ipsilateral SVZ on day 14 of the FES treatment group （（522.77±33.32） cells/mm2） was significantly increased compared with the control group （（262.58±35.11） cells/mm2,P 〈0.05） and the placebo group （（266.17±47.98） cells/mm2,P 〈0.05）.However,only a few BrdU/neuron-specific nuclear protein-positive cells were observed by day 14 of the treatment.At day 7,Wnt-3 was upregulated in the ipsilateral SVZs of the rats receiving FES （（0.44±0.05）%） compared with those of the control group rats （（0.31±0.02）%,P 〈0.05） or the placebo group rats （（0.31±0.04）%,P 〈0.05）.At day 14,the corresponding values were （0.56±0.05）% in the FES group compared with those of the control group rats （（0.50±0.06）%,P 〈0.05） or the placebo group rats （（0.48±0.06）%,P 〈0.05）.Conclusion FES augments the proliferation,differentiation,and migration of NSCs and thus promotes neurogenesis,which may be related to the improvement of neurological outcomes.
文摘BACKGROUND： The origin and classification of neural stem cells （NSCs） has been a subject of intense investigation for the past two decades. Efforts to categorize NSCs based on their location, function and expression have established that these cells are a heterogeneous pool in both the embryonic and adult brain. The discovery and additional characterization of adult NSCs has introduced the possibility of using these cells as a source for neuronal and glial replacement following injury or disease. To understand how one could manipulate NSC developmental programs for therapeutic use, additional work is needed to elucidate how NSCs are programmed and how signals during development are interpreted to determine cell fate. OBJECTIVE： This review describes the identification, classification and characterization of NSCs within the large neurogenic niche of the ventricular-subventricular zone （V-SVZ）. METHODS： A literature search was conducted using Pubmed including the keywords ＂ventricular-subventricular zone,＂ ＂neural stem cell,＂ ＂heterogeneity,＂ ＂identity＂ and/or ＂single cell＂ to find relevant manuscripts to include within the review. A special focus was placed on more recent findings using single-cell level analyses on neural stem cells within their niche（s）. RESULTS： This review discusses over 20 research articles detailing findings on V-SVZ NSC heterogeneity, over 25 articles describing fate determinants of NSCs, and focuses on 8 recent publications using distinct single-cell analyses of neural stem cells including fl0w cytometry and RNA-seq. Additionally, over 60 manuscripts highlighting the markers expressed on cells within the NSC lineage are included in a chart divided by cell type. CONCLUSIONS： Investigation of NSC heterogeneity and fate decisions is ongoing. Thus far, much research has been conducted in mice however, findings in human and other mammalian species are also discussed here. Implications of NSC heterogeneity established in the embryo for the properties of NSCs in the adult brain are explored, including how these cells may be redirected after injury or genetic manipulation.
基金supported by the National Natural Science Foundation of ChinaNos.82272171 (to ZY),82271403 (to XL),31971279 (to ZY),81941011 (to XL),31730030 (to XL)。
文摘It has long been asserted that failure to recover from central nervous system diseases is due to the system's intricate structure and the regenerative incapacity of adult neurons.Yet over recent decades,numerous studies have established that endogenous neurogenesis occurs in the adult central nervous system,including humans'.This has challenged the long-held scientific consensus that the number of adult neurons remains constant,and that new central nervous system neurons cannot be created or renewed.Herein,we present a comprehensive overview of the alterations and regulatory mechanisms of endogenous neurogenesis following central nervous system injury,and describe novel treatment strategies that to rget endogenous neurogenesis and newborn neurons in the treatment of central nervous system injury.Central nervous system injury frequently results in alterations of endogenous neurogenesis,encompassing the activation,proliferation,ectopic migration,diffe rentiation,and functional integration of endogenous neural stem cells.Because of the unfavorable local microenvironment,most activated neural stem cells diffe rentiate into glial cells rather than neurons.Consequently,the injury-induced endogenous neurogenesis response is inadequate for repairing impaired neural function.Scientists have attempted to enhance endogenous neurogenesis using various strategies,including using neurotrophic factors,bioactive materials,and cell reprogramming techniques.Used alone or in combination,these therapeutic strategies can promote targeted migration of neural stem cells to an injured area,ensure their survival and diffe rentiation into mature functional neurons,and facilitate their integration into the neural circuit.Thus can integration re plenish lost neurons after central nervous system injury,by improving the local microenvironment.By regulating each phase of endogenous neurogenesis,endogenous neural stem cells can be harnessed to promote effective regeneration of newborn neurons.This offers a novel approach for treating central nervous system injury.
基金This work was supported by Grant from National Natural ScienceFoundation of China (30200291, 30170300) and Natural Science Foundation of Shaanxi Province,China(2002C250,2001SM63).
