Apelin-13 is a novel endogenous ligand for an angiotensin-like orphan G-protein coupled receptor,and it may be neuroprotective against cerebral ischemia injury.However,the precise mechanisms of the effects of apelin-1...Apelin-13 is a novel endogenous ligand for an angiotensin-like orphan G-protein coupled receptor,and it may be neuroprotective against cerebral ischemia injury.However,the precise mechanisms of the effects of apelin-13 remain to be elucidated.To investigate the effects of apelin-13 on apoptosis and autophagy in models of cerebral ischemia/reperfusion injury,a rat model was established by middle cerebral artery occlusion.Apelin-13(50μg/kg)was injected into the right ventricle as a treatment.In addition,an SH-SY5Y cell model was established by oxygen-glucose deprivation/reperfusion,with cells first cultured in sugar-free medium with 95%N2 and 5%CO2 for 4 hours and then cultured in a normal environment with sugar-containing medium for 5 hours.This SH-SY5Y cell model was treated with 10-7 M apelin-13 for 5 hours.Results showed that apelin-13 protected against cerebral ischemia/reperfusion injury.Apelin-13 treatment alleviated neuronal apoptosis by increasing the ratio of Bcl-2/Bax and significantly decreasing cleaved caspase-3 expression.In addition,apelin-13 significantly inhibited excessive autophagy by regulating the expression of LC3B,p62,and Beclin1.Furthermore,the expression of Bcl-2 and the phosphatidylinositol-3-kinase(PI3K)/Akt/mammalian target of rapamycin(mTOR)pathway was markedly increased.Both LY294002(20μM)and rapamycin(500 nM),which are inhibitors of the PI3K/Akt/mTOR pathway,significantly attenuated the inhibition of autophagy and apoptosis caused by apelin-13.In conclusion,the findings of the present study suggest that Bcl-2 upregulation and mTOR signaling pathway activation lead to the inhibition of apoptosis and excessive autophagy.These effects are involved in apelin-13-induced neuroprotection against cerebral ischemia/reperfusion injury,both in vivo and in vitro.The study was approved by the Animal Ethical and Welfare Committee of Jining Medical University,China(approval No.2018-JS-001)in February 2018.展开更多
Many hypotheses exist regarding the mechanism underlying delayed encephalopathy after acute carbon monoxide poisoning(DEACMP),including the inflammation and immune-mediated damage hypothesis and the cellular apoptosis...Many hypotheses exist regarding the mechanism underlying delayed encephalopathy after acute carbon monoxide poisoning(DEACMP),including the inflammation and immune-mediated damage hypothesis and the cellular apoptosis and direct neuronal toxicity hypothesis;however,no existing hypothesis provides a satisfactory explanation for the complex clinical processes observed in DEACMP.Leucine-rich repeat and immunoglobulin-like domain-containing protein-1(LINGO-1)activates the Ras homolog gene family member A(Rho A)/Rho-associated coiled-coil containing protein kinase 2(ROCK2)signaling pathway,which negatively regulates oligodendrocyte myelination,axonal growth,and neuronal survival,causing myelin damage and participating in the pathophysiological processes associated with many central nervous system diseases.However,whether LINGO-1 is involved in DEACMP remains unclear.A DEACMP model was established in rats by allowing them to inhale 1000 ppm carbon monoxide gas for 40 minutes,followed by 3000 ppm carbon monoxide gas for an additional 20 minutes.The results showed that compared with control rats,DEACMP rats showed significantly increased water maze latency and increased protein and m RNA expression levels of LINGO-1,Rho A,and ROCK2 in the brain.Compared with normal rats,significant increases in injured neurons in the hippocampus and myelin sheath damage in the lateral geniculate body were observed in DEACMP rats.From days 1 to 21 after DEACMP,the intraperitoneal injection of retinoic acid(10 mg/kg),which can inhibit LINGO-1 expression,was able to improve the above changes observed in the DEACMP model.Therefore,the overexpression of LINGO-1 appeared to increase following carbon monoxide poisoning,activating the Rho A/ROCK2 signaling pathway,which may be an important pathophysiological mechanism underlying DEACMP.This study was reviewed and approved by the Medical Ethics Committee of Xiangya Hospital of Central South Hospital(approval No.201612684)on December 26,2016.展开更多
Our previous studies showed that ferroptosis plays an important role in the acute and subacute stages of spinal cord injury.High intracellular iron levels and low glutathione levels make oligodendrocytes vulnerable to...Our previous studies showed that ferroptosis plays an important role in the acute and subacute stages of spinal cord injury.High intracellular iron levels and low glutathione levels make oligodendrocytes vulnerable to cell death after central nervous system trauma.In this study,we established an oligodendrocyte(OLN-93 cell line)model of ferroptosis induced by RSL-3,an inhibitor of glutathione peroxidase 4(GPX4).RSL-3 significantly increased intracellular concentrations of reactive oxygen species and malondialdehyde.RSL-3 also inhibited the main antiferroptosis pathway,i.e.,SLC7A11/glutathione/glutathione peroxidase 4(xCT/GSH/GPX4),and downregulated acyl-coenzyme A synthetase long chain family member 4.Furthermore,we evaluated the ability of several compounds to rescue oligodendrocytes from ferroptosis.Liproxstatin-1 was more potent than edaravone or deferoxamine.Liproxstatin-1 not only inhibited mitochondrial lipid peroxidation,but also restored the expression of GSH,GPX4 and ferroptosis suppressor protein 1.These findings suggest that GPX4 inhibition induces ferroptosis in oligodendrocytes,and that liproxstatin-1 is a potent inhibitor of ferroptosis.Therefore,liproxstatin-1 may be a promising drug for the treatment of central nervous system diseases.展开更多
Microglia-associated neuroinflammation plays an important role in the pathophysiology of ischemic stroke.Microglial activation and polarization,and the inflammatory response mediated by these cells play important role...Microglia-associated neuroinflammation plays an important role in the pathophysiology of ischemic stroke.Microglial activation and polarization,and the inflammatory response mediated by these cells play important roles in the development,progression and outcome of brain injury after ischemic stroke.Currently,there is no effective strategy for treating ischemic stroke in clinical practice.Therefore,it is clinically important to study the role and regulation of microglia in stroke.In this review,we discuss the involvement of microglia in the neuroinflammatory process in ischemic stroke,with the aim of providing a better understanding of the relationship between ischemic stroke and microglia.展开更多
Autophagy is crucial for maintaining cellular homeostasis,and can be activated after ischemic stroke.It also participates in nerve injury and repair.The purpose of this study was to investigate whether an enriched env...Autophagy is crucial for maintaining cellular homeostasis,and can be activated after ischemic stroke.It also participates in nerve injury and repair.The purpose of this study was to investigate whether an enriched environment has neuroprotective effects through affecting autophagy.A Sprague-Dawley rat model of transient ischemic stroke was prepared by occlusion of the middle cerebral artery followed by reperfusion.One week after surgery,these rats were raised in either a standard environment or an enriched environment for 4 successive weeks.The enriched environment increased Beclin-1 expression and the LC3-II/LC3-I ratio in the autophagy/lysosomal pathway in the penumbra of middle cerebral artery-occluded rats.Enriched environment-induced elevations in autophagic activity were mainly observed in neurons.Enriched environment treatment also promoted the fusion of autophagosomes with lysosomes,enhanced the lysosomal activities of lysosomal-associated membrane protein 1,cathepsin B,and cathepsin D,and reduced the expression of ubiquitin and p62.After 4 weeks of enriched environment treatment,neurological deficits and neuronal death caused by middle cerebral artery occlusion/reperfusion were significantly alleviated,and infarct volume was significantly reduced.These findings suggest that neuronal autophagy is likely the neuroprotective mechanism by which an enriched environment promotes recovery from ischemic stroke.This study was approved by the Animal Ethics Committee of the Kunming University of Science and Technology,China(approval No.5301002013855)on March 1,2019.展开更多
Spinal cord injury can lead to severe motor,sensory and autonomic nervous dysfunctions.However,there is currently no effective treatment for spinal cord injury.Neural stem cells and progenitor cells,bone marrow mesenc...Spinal cord injury can lead to severe motor,sensory and autonomic nervous dysfunctions.However,there is currently no effective treatment for spinal cord injury.Neural stem cells and progenitor cells,bone marrow mesenchymal stem cells,olfactory ensheathing cells,umbilical cord blood stem cells,adipose stem cells,hematopoietic stem cells,oligodendrocyte precursor cells,macrophages and Schwann cells have been studied as potential treatments for spinal cord injury.These treatments were mainly performed in animals.However,subtle changes in sensory function,nerve root movement and pain cannot be fully investigated with animal studies.Although these cell types have shown excellent safety and effectiveness in various animal models,sufficient evidence of efficacy for clinical translation is still lacking.Cell transplantation should be combined with tissue engineering scaffolds,local drug delivery systems,postoperative adjuvant therapy and physical rehabilitation training as part of a comprehensive treatment plan to provide the possibility for patients with SCI to return to normal life.This review summarizes and analyzes the clinical trials of cell transplantation therapy in spinal cord injury,with the aim of providing a rational foundation for the development of clinical treatments for spinal cord injury.展开更多
MiR-219 and miR-338(miR-219/miR-338)are oligodendrocyte-specific microRNAs.The overexpression of these miRs in oligodendrocyte precursor cells promotes their differentiation and maturation into oligodendrocytes,which ...MiR-219 and miR-338(miR-219/miR-338)are oligodendrocyte-specific microRNAs.The overexpression of these miRs in oligodendrocyte precursor cells promotes their differentiation and maturation into oligodendrocytes,which may enhance axonal remyelination after nerve injuries in the central nervous system(CNS).As such,the delivery of miR-219/miR-338 to the CNS to promote oligodendrocyte precursor cell differentiation,maturation and myelination could be a promising approach for nerve repair.However,nerve injuries in the CNS also involve other cell types,such as microglia and astrocytes.Herein,we investigated the effects of miR-219/miR-338 treatment on microglia and astrocytes in vitro and in vivo.We found that miR-219/miR-338 diminished microglial expression of pro-inflammatory cytokines and suppressed astrocyte activation.In addition,we showed that miR-219/miR-338 enhanced oligodendrocyte precursor cell differentiation and maturation in a scratch assay paradigm that re-created a nerve injury condition in vitro.Collectively,our results suggest miR-219/miR-338 as a promising treatment for axonal remyelination in the CNS following nerve injuries.All experimental procedures were approved by the Institutional Animal Care and Use Committee(IACUC),Nanyang Technological University(approval No.A0309 and A0333)on April 27,2016 and October 8,2016.展开更多
As the average age of the world population increases,more people will face debilitating aging-associated conditions,including dementia and stroke.Not only does the incidence of these conditions increase with age,but t...As the average age of the world population increases,more people will face debilitating aging-associated conditions,including dementia and stroke.Not only does the incidence of these conditions increase with age,but the recovery afterward is often worse in older patients.Researchers and health professionals must unveil and understand the factors behind age-associated diseases to develop a therapy for older patients.Aging causes profound changes in the immune system including the activation of microglia in the brain.Activated microglia promote T lymphocyte transmigration leading to an increase in neuroinflammation,white matter damage,and cognitive impairment in both older humans and rodents.The presence of T and B lymphocytes is observed in the aged brain and correlates with worse stroke outcomes.Preclinical strategies in stroke target either microglia or the lymphocytes or the communications between them to promote functional recovery in aged subjects.In this review,we examine the role of the microglia and T and B lymphocytes in aging and how they contribute to cognitive impairment.Additionally,we provide an important update on the contribution of these cells and their interactions in preclinical aged stroke.展开更多
Spinal cord injury results in the permanent loss of function, causing enormous personal, social and economic problems. Even though neural regeneration has been proven to be a natural mech- anism, central nervous syste...Spinal cord injury results in the permanent loss of function, causing enormous personal, social and economic problems. Even though neural regeneration has been proven to be a natural mech- anism, central nervous system repair mechanisms are ineffective due to the imbalance of the inhibitory and excitatory factors implicated in neuroregeneration. Therefore, there is growing re- search interest on discovering a novel therapeutic strategy for effective spinal cord injury repair. To this direction, cell-based delivery strategies, biomolecule delivery strategies as well as scaf- fold-based therapeutic strategies have been developed with a tendency to seek for the answer to a combinatorial approach of all the above. Here we review the recent advances on regenerativel neural engineering therapies for spinal cord injury, aiming at providing an insight to the most promising repair strategies, in order to facilitate future research conduction.展开更多
The lymphatic vasculature forms an organized network that covers the whole body and is involved in fluid homeostasis,metabolite clearance,and immune surveillance.The recent identification of functional lymphatic vesse...The lymphatic vasculature forms an organized network that covers the whole body and is involved in fluid homeostasis,metabolite clearance,and immune surveillance.The recent identification of functional lymphatic vessels in the meninges of the brain and the spinal cord has provided novel insights into neurophysiology.They emerge as major pathways for fluid exchange.The abundance of immune cells in lymphatic vessels and meninges also suggests that lymphatic vessels are actively involved in neuroimmunity.The lymphatic system,through its role in the clearance of neurotoxic proteins,autoimmune cell infiltration,and the transmission of pro-inflammatory signals,participates in the pathogenesis of a variety of neurological disorders,including neurodegenerative and neuroinflammatory diseases and traumatic injury.Vascular endothelial growth factor C is the master regulator of lymphangiogenesis,a process that is critical for the maintenance of central nervous system homeostasis.In this review,we summarize current knowledge and recent advances relating to the anatomical features and immunological functions of the lymphatic system of the central nervous system and highlight its potential as a therapeutic target for neurological disorders and central nervous system repair.展开更多
创伤后的神经胶质增生导致硫酸软骨素蛋白聚糖(CSPG)的显著表达,从而抑制轴突生长和再生。甲基强地松龙(MP),一种合成的糖皮质激素,在急性脊髓损伤(SCI)的治疗中有神经保护作用和抗炎效应。但是,MP对于CSPG在活性胶质细胞中的表达的作...创伤后的神经胶质增生导致硫酸软骨素蛋白聚糖(CSPG)的显著表达,从而抑制轴突生长和再生。甲基强地松龙(MP),一种合成的糖皮质激素,在急性脊髓损伤(SCI)的治疗中有神经保护作用和抗炎效应。但是,MP对于CSPG在活性胶质细胞中的表达的作用尚不清楚。本文用a-氨基-3-羟基-5-甲基-4-异恶唑丙酸酯(AM-PA)诱导星形胶质细胞再活化,用环噻嗪模拟SCI的兴奋性中毒刺激。AMPA治疗后,星形胶质细胞再活化的标志物-胶质纤维酸性蛋白(GFAP)、CSPG神经聚糖和磷酸盐的表达都显著上调。AMPA治疗星形胶质细胞的条件培养液强烈抑制大鼠背根神经节中神经元的轴突生长,但这种作用能被MP的预处理所逆转。此外,MP下调成年SCI大鼠中GFAP和CSPG的表达,对抗RU486的糖皮质激素受体(GR)和GR si RNA能逆转MP对GFAP和神经聚糖表达的抑制作用。这些结果提示,MP能在兴奋性中毒损伤后通过GR介导的星形胶质细胞再活化下调和GSPG表达抑制来改善神经修复,促进轴突生长。展开更多
基金supported by the National Natural Science Foundation of China,Nos.81870948(to BB),81671276(to BHC),81501018(to CMW)the Natural Science Foundation of Shandong Province of China,No.ZR2014HL040(to BHC)Program Supporting Foundation for Teachers’Research of Jining Medical University of China,No.JYFC2018KJ003(to SSD).
文摘Apelin-13 is a novel endogenous ligand for an angiotensin-like orphan G-protein coupled receptor,and it may be neuroprotective against cerebral ischemia injury.However,the precise mechanisms of the effects of apelin-13 remain to be elucidated.To investigate the effects of apelin-13 on apoptosis and autophagy in models of cerebral ischemia/reperfusion injury,a rat model was established by middle cerebral artery occlusion.Apelin-13(50μg/kg)was injected into the right ventricle as a treatment.In addition,an SH-SY5Y cell model was established by oxygen-glucose deprivation/reperfusion,with cells first cultured in sugar-free medium with 95%N2 and 5%CO2 for 4 hours and then cultured in a normal environment with sugar-containing medium for 5 hours.This SH-SY5Y cell model was treated with 10-7 M apelin-13 for 5 hours.Results showed that apelin-13 protected against cerebral ischemia/reperfusion injury.Apelin-13 treatment alleviated neuronal apoptosis by increasing the ratio of Bcl-2/Bax and significantly decreasing cleaved caspase-3 expression.In addition,apelin-13 significantly inhibited excessive autophagy by regulating the expression of LC3B,p62,and Beclin1.Furthermore,the expression of Bcl-2 and the phosphatidylinositol-3-kinase(PI3K)/Akt/mammalian target of rapamycin(mTOR)pathway was markedly increased.Both LY294002(20μM)and rapamycin(500 nM),which are inhibitors of the PI3K/Akt/mTOR pathway,significantly attenuated the inhibition of autophagy and apoptosis caused by apelin-13.In conclusion,the findings of the present study suggest that Bcl-2 upregulation and mTOR signaling pathway activation lead to the inhibition of apoptosis and excessive autophagy.These effects are involved in apelin-13-induced neuroprotection against cerebral ischemia/reperfusion injury,both in vivo and in vitro.The study was approved by the Animal Ethical and Welfare Committee of Jining Medical University,China(approval No.2018-JS-001)in February 2018.
文摘Many hypotheses exist regarding the mechanism underlying delayed encephalopathy after acute carbon monoxide poisoning(DEACMP),including the inflammation and immune-mediated damage hypothesis and the cellular apoptosis and direct neuronal toxicity hypothesis;however,no existing hypothesis provides a satisfactory explanation for the complex clinical processes observed in DEACMP.Leucine-rich repeat and immunoglobulin-like domain-containing protein-1(LINGO-1)activates the Ras homolog gene family member A(Rho A)/Rho-associated coiled-coil containing protein kinase 2(ROCK2)signaling pathway,which negatively regulates oligodendrocyte myelination,axonal growth,and neuronal survival,causing myelin damage and participating in the pathophysiological processes associated with many central nervous system diseases.However,whether LINGO-1 is involved in DEACMP remains unclear.A DEACMP model was established in rats by allowing them to inhale 1000 ppm carbon monoxide gas for 40 minutes,followed by 3000 ppm carbon monoxide gas for an additional 20 minutes.The results showed that compared with control rats,DEACMP rats showed significantly increased water maze latency and increased protein and m RNA expression levels of LINGO-1,Rho A,and ROCK2 in the brain.Compared with normal rats,significant increases in injured neurons in the hippocampus and myelin sheath damage in the lateral geniculate body were observed in DEACMP rats.From days 1 to 21 after DEACMP,the intraperitoneal injection of retinoic acid(10 mg/kg),which can inhibit LINGO-1 expression,was able to improve the above changes observed in the DEACMP model.Therefore,the overexpression of LINGO-1 appeared to increase following carbon monoxide poisoning,activating the Rho A/ROCK2 signaling pathway,which may be an important pathophysiological mechanism underlying DEACMP.This study was reviewed and approved by the Medical Ethics Committee of Xiangya Hospital of Central South Hospital(approval No.201612684)on December 26,2016.
基金supported by the National Natural Science Foundation of China,Nos.81672171(to XY),81972074(to XY),81930070(to SQF),81620108018(to SQF),and 81772342(to GZN)the National Key R&D Program of China,No.2019YFA0112100(to SQF)the Natural Science Foundation of Tianjin of China,No.19JCZDJC34900(to XY)。
文摘Our previous studies showed that ferroptosis plays an important role in the acute and subacute stages of spinal cord injury.High intracellular iron levels and low glutathione levels make oligodendrocytes vulnerable to cell death after central nervous system trauma.In this study,we established an oligodendrocyte(OLN-93 cell line)model of ferroptosis induced by RSL-3,an inhibitor of glutathione peroxidase 4(GPX4).RSL-3 significantly increased intracellular concentrations of reactive oxygen species and malondialdehyde.RSL-3 also inhibited the main antiferroptosis pathway,i.e.,SLC7A11/glutathione/glutathione peroxidase 4(xCT/GSH/GPX4),and downregulated acyl-coenzyme A synthetase long chain family member 4.Furthermore,we evaluated the ability of several compounds to rescue oligodendrocytes from ferroptosis.Liproxstatin-1 was more potent than edaravone or deferoxamine.Liproxstatin-1 not only inhibited mitochondrial lipid peroxidation,but also restored the expression of GSH,GPX4 and ferroptosis suppressor protein 1.These findings suggest that GPX4 inhibition induces ferroptosis in oligodendrocytes,and that liproxstatin-1 is a potent inhibitor of ferroptosis.Therefore,liproxstatin-1 may be a promising drug for the treatment of central nervous system diseases.
基金This work was supported by the National Natural Science Foundation of China,Nos.31871169(to YT),81600040(to APW)Key Project of Department of Education of Hunan Province,China,No.18A243(to APW)+1 种基金Innovation Guidance Project of Hunan Province,China,No.2018SK51606(to SXG)the Natural Science Foundation of Hunan Province of China,No.2017JJ3279(to APW).
文摘Microglia-associated neuroinflammation plays an important role in the pathophysiology of ischemic stroke.Microglial activation and polarization,and the inflammatory response mediated by these cells play important roles in the development,progression and outcome of brain injury after ischemic stroke.Currently,there is no effective strategy for treating ischemic stroke in clinical practice.Therefore,it is clinically important to study the role and regulation of microglia in stroke.In this review,we discuss the involvement of microglia in the neuroinflammatory process in ischemic stroke,with the aim of providing a better understanding of the relationship between ischemic stroke and microglia.
基金This work was supported by the National Natural Science Foundation of China,Nos.81660383(to YHD),81860411(to HYH),81960418(to YHD)Yunnan Ten Thousand Talents Plan Young&Elite Talents Project of China,No.YNWR-QNBJ-2018-034(to YHD)+1 种基金Applied Basic Research Foundation of Yunnan Province of China,Nos.2017FB113(to YHD),2019FB098(to HYH)Science Research Fund of Yunnan Provincial Department of Education of China,No.2018JS016(to HYH).
文摘Autophagy is crucial for maintaining cellular homeostasis,and can be activated after ischemic stroke.It also participates in nerve injury and repair.The purpose of this study was to investigate whether an enriched environment has neuroprotective effects through affecting autophagy.A Sprague-Dawley rat model of transient ischemic stroke was prepared by occlusion of the middle cerebral artery followed by reperfusion.One week after surgery,these rats were raised in either a standard environment or an enriched environment for 4 successive weeks.The enriched environment increased Beclin-1 expression and the LC3-II/LC3-I ratio in the autophagy/lysosomal pathway in the penumbra of middle cerebral artery-occluded rats.Enriched environment-induced elevations in autophagic activity were mainly observed in neurons.Enriched environment treatment also promoted the fusion of autophagosomes with lysosomes,enhanced the lysosomal activities of lysosomal-associated membrane protein 1,cathepsin B,and cathepsin D,and reduced the expression of ubiquitin and p62.After 4 weeks of enriched environment treatment,neurological deficits and neuronal death caused by middle cerebral artery occlusion/reperfusion were significantly alleviated,and infarct volume was significantly reduced.These findings suggest that neuronal autophagy is likely the neuroprotective mechanism by which an enriched environment promotes recovery from ischemic stroke.This study was approved by the Animal Ethics Committee of the Kunming University of Science and Technology,China(approval No.5301002013855)on March 1,2019.
基金supported by 2019 Scientific Research Project of Traditional Chinese Medicine in Gansu Province of China,No.GZK-2019-46(to XWK and YBL)。
文摘Spinal cord injury can lead to severe motor,sensory and autonomic nervous dysfunctions.However,there is currently no effective treatment for spinal cord injury.Neural stem cells and progenitor cells,bone marrow mesenchymal stem cells,olfactory ensheathing cells,umbilical cord blood stem cells,adipose stem cells,hematopoietic stem cells,oligodendrocyte precursor cells,macrophages and Schwann cells have been studied as potential treatments for spinal cord injury.These treatments were mainly performed in animals.However,subtle changes in sensory function,nerve root movement and pain cannot be fully investigated with animal studies.Although these cell types have shown excellent safety and effectiveness in various animal models,sufficient evidence of efficacy for clinical translation is still lacking.Cell transplantation should be combined with tissue engineering scaffolds,local drug delivery systems,postoperative adjuvant therapy and physical rehabilitation training as part of a comprehensive treatment plan to provide the possibility for patients with SCI to return to normal life.This review summarizes and analyzes the clinical trials of cell transplantation therapy in spinal cord injury,with the aim of providing a rational foundation for the development of clinical treatments for spinal cord injury.
基金supported by the Singapore National Research Foundation under its NMRC-CBRG grants(Project award number:NMRC/CBRG/0096/2015) and administered by the Singapore Ministry of Health’s National Medical Research Councilpartially supported by the MOE Academic Research Funding(AcRF) Tier 1 grant(RG148/14) and Tier 2 grant(MOE2015-T2-1-023)
文摘MiR-219 and miR-338(miR-219/miR-338)are oligodendrocyte-specific microRNAs.The overexpression of these miRs in oligodendrocyte precursor cells promotes their differentiation and maturation into oligodendrocytes,which may enhance axonal remyelination after nerve injuries in the central nervous system(CNS).As such,the delivery of miR-219/miR-338 to the CNS to promote oligodendrocyte precursor cell differentiation,maturation and myelination could be a promising approach for nerve repair.However,nerve injuries in the CNS also involve other cell types,such as microglia and astrocytes.Herein,we investigated the effects of miR-219/miR-338 treatment on microglia and astrocytes in vitro and in vivo.We found that miR-219/miR-338 diminished microglial expression of pro-inflammatory cytokines and suppressed astrocyte activation.In addition,we showed that miR-219/miR-338 enhanced oligodendrocyte precursor cell differentiation and maturation in a scratch assay paradigm that re-created a nerve injury condition in vitro.Collectively,our results suggest miR-219/miR-338 as a promising treatment for axonal remyelination in the CNS following nerve injuries.All experimental procedures were approved by the Institutional Animal Care and Use Committee(IACUC),Nanyang Technological University(approval No.A0309 and A0333)on April 27,2016 and October 8,2016.
基金supported by 16POST27490032 American Heart Association post-doctoral fellowshipNational Institute of Neurological Disorders and Stroke Exploratory Neuroscience Research Grant R21 NS114836-01A1 (to AC)
文摘As the average age of the world population increases,more people will face debilitating aging-associated conditions,including dementia and stroke.Not only does the incidence of these conditions increase with age,but the recovery afterward is often worse in older patients.Researchers and health professionals must unveil and understand the factors behind age-associated diseases to develop a therapy for older patients.Aging causes profound changes in the immune system including the activation of microglia in the brain.Activated microglia promote T lymphocyte transmigration leading to an increase in neuroinflammation,white matter damage,and cognitive impairment in both older humans and rodents.The presence of T and B lymphocytes is observed in the aged brain and correlates with worse stroke outcomes.Preclinical strategies in stroke target either microglia or the lymphocytes or the communications between them to promote functional recovery in aged subjects.In this review,we examine the role of the microglia and T and B lymphocytes in aging and how they contribute to cognitive impairment.Additionally,we provide an important update on the contribution of these cells and their interactions in preclinical aged stroke.
基金funded by the Program "IKY(Greek State Scholarships Foundation)Scholarships" from funds of the Operational Program "Education and Lifelong Learning"the European Social Fund(ESF)of the National Strategic Reference Framework(NSRF),2007-2013+2 种基金funded by Scholarships from the A.G.Leventis Foundationa Scholarship from John S.Latsis Public Benefit Foundationa special Scholarship from the Faculty of Medicine of the University of Thessaly(Greece)
文摘Spinal cord injury results in the permanent loss of function, causing enormous personal, social and economic problems. Even though neural regeneration has been proven to be a natural mech- anism, central nervous system repair mechanisms are ineffective due to the imbalance of the inhibitory and excitatory factors implicated in neuroregeneration. Therefore, there is growing re- search interest on discovering a novel therapeutic strategy for effective spinal cord injury repair. To this direction, cell-based delivery strategies, biomolecule delivery strategies as well as scaf- fold-based therapeutic strategies have been developed with a tendency to seek for the answer to a combinatorial approach of all the above. Here we review the recent advances on regenerativel neural engineering therapies for spinal cord injury, aiming at providing an insight to the most promising repair strategies, in order to facilitate future research conduction.
基金supported by the Key Program of the National Natural Science Foundation of ChinaNo.82030071+1 种基金the Science and Technology Major Project of ChangshaNo.kh2103008 (both to JZH)
文摘The lymphatic vasculature forms an organized network that covers the whole body and is involved in fluid homeostasis,metabolite clearance,and immune surveillance.The recent identification of functional lymphatic vessels in the meninges of the brain and the spinal cord has provided novel insights into neurophysiology.They emerge as major pathways for fluid exchange.The abundance of immune cells in lymphatic vessels and meninges also suggests that lymphatic vessels are actively involved in neuroimmunity.The lymphatic system,through its role in the clearance of neurotoxic proteins,autoimmune cell infiltration,and the transmission of pro-inflammatory signals,participates in the pathogenesis of a variety of neurological disorders,including neurodegenerative and neuroinflammatory diseases and traumatic injury.Vascular endothelial growth factor C is the master regulator of lymphangiogenesis,a process that is critical for the maintenance of central nervous system homeostasis.In this review,we summarize current knowledge and recent advances relating to the anatomical features and immunological functions of the lymphatic system of the central nervous system and highlight its potential as a therapeutic target for neurological disorders and central nervous system repair.
文摘创伤后的神经胶质增生导致硫酸软骨素蛋白聚糖(CSPG)的显著表达,从而抑制轴突生长和再生。甲基强地松龙(MP),一种合成的糖皮质激素,在急性脊髓损伤(SCI)的治疗中有神经保护作用和抗炎效应。但是,MP对于CSPG在活性胶质细胞中的表达的作用尚不清楚。本文用a-氨基-3-羟基-5-甲基-4-异恶唑丙酸酯(AM-PA)诱导星形胶质细胞再活化,用环噻嗪模拟SCI的兴奋性中毒刺激。AMPA治疗后,星形胶质细胞再活化的标志物-胶质纤维酸性蛋白(GFAP)、CSPG神经聚糖和磷酸盐的表达都显著上调。AMPA治疗星形胶质细胞的条件培养液强烈抑制大鼠背根神经节中神经元的轴突生长,但这种作用能被MP的预处理所逆转。此外,MP下调成年SCI大鼠中GFAP和CSPG的表达,对抗RU486的糖皮质激素受体(GR)和GR si RNA能逆转MP对GFAP和神经聚糖表达的抑制作用。这些结果提示,MP能在兴奋性中毒损伤后通过GR介导的星形胶质细胞再活化下调和GSPG表达抑制来改善神经修复,促进轴突生长。
