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
Background: Spinal cord injury (SCI) is a worldwide medical concern. This study aimed to elucidate the mechanism underlying protective effect of hyperbaric oxygen (HBO) against SCI-induced neurologic defects in rats v...Background: Spinal cord injury (SCI) is a worldwide medical concern. This study aimed to elucidate the mechanism underlying protective effect of hyperbaric oxygen (HBO) against SCI-induced neurologic defects in rats via exploring the stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor 4 (CXCR4) axis and expression of brain-derived neurotrophic factor (BDNF). Methods: An acute SCI rat model was established in Sprague-Dawley rats using the Allen method. Sixty rats were divided into four groups (w = 15 in each group): sham-operated, SCI, SCI treated with HBO (SCI + HBO), and SCI treated with both HBO and AMD3100 (an antagonist of CXCR4;SCI + HBO + AMD) groups. The rats were treated with HBO twice a day for 3 days and thereafter once a day after the surgery for up to 28 days. Following the surgery, neurologic assessments were performed with the Basso-Bettie-Bresnahan (BBB) scoring system on postoperative day (POD) 7, 14, 21, and 28. Spinal cord tissues were harvested to assess the expression of SDF-1, CXCR4, and BDNF at mRNA and protein levels, using quantitative real-time polymerase chain reaction, Western blot analysis, and histopathologic analysis. Results: HBO treatment recovered SCI-induced descent of BBB scores on POD 14,(1.25±0.75 vs. 1.03 ±0.66, P< 0.05), 21 (5.27± 0.89 vs. 2.56± 1.24, P< 0.05), and 28 (11.35±0.56 vs. 4.23± 1.20, P<0.05) compared with the SCI group. Significant differences were found in the mRNA levels of SDF-1 (mRNA: day 21, SCI + HBO vs. SCI + HBO + AMD, 2.89± 1.60 vs. 1.56±0.98, P<0.05), CXCR4 (mRNA: day 7, SCI + HBO vs. SCI, 2.99± 1.60 vs. 1.31 ±0.98, P<0.05;day 14, SCI + HBO vs. SCI + HBO + AMD, 4.18± 1.60 vs. 0.80±0.34, P<0.05;day 21, SCI + HBO vs. SCI, 2.10±1.01 vs.1.15±0.03, P<0.05), and BDNF (mRNA: day 7, SCI + HBO vs. SCI, 3.04±0.41 vs. 2.75±0.31, P<0.05;day 14, SCI + HBO vs. SCI, 3.88± 1.59 vs. 1.11 ±0.40, P<0.05), indicating the involvement of SDF-1/CXCR4 axis in the protective effect of HBO. Conclusions: HBO might promote the recovery of neurologic func展开更多
Neurodegenerative diseases,including Alzheimer’s disease,Parkinson’s disease,Huntington’s disease and amyotrophic lateral sclerosis,are a group of incurable neurological disorders,characterized by the chronic progr...Neurodegenerative diseases,including Alzheimer’s disease,Parkinson’s disease,Huntington’s disease and amyotrophic lateral sclerosis,are a group of incurable neurological disorders,characterized by the chronic progressive loss of different neuronal subtypes.However,despite its increasing prevalence among the everincreasing aging population,little progress has been made in the coincident immense efforts towards development of therapeutic agents.Research interest has recently turned towards stem cells including stem cells-derived exosomes,neurotrophic factors,and their combination as potential therapeutic agents in neurodegenerative diseases.In this review,we summarize the progress in therapeutic strategies based on stem cells combined with neurotrophic factors and mesenchymal stem cells-derived exosomes for neurodegenerative diseases,with an emphasis on the combination therapy.展开更多
Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postu...Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postural instability,as a result of the progressive loss of nigrostriatal dopaminergic neurons.In addition to this neuronal cell loss,Parkinson’s disease is characterized by the accumulation of intracellular protein aggregates,Lewy bodies and Lewy neurites,composed primarily of the proteinα-synuclein.Although it was first described almost 200 years ago,there are no disease-modifying drugs to treat patients with Parkinson’s disease.In addition to conventional therapies,non-pharmacological treatment strategies are under investigation in patients and animal models of neurodegenerative disorders.Among such strategies,environmental enrichment,comprising physical exercise,cognitive stimulus,and social interactions,has been assessed in preclinical models of Parkinson’s disease.Environmental enrichment can cause structural and functional changes in the brain and promote neurogenesis and dendritic growth by modifying gene expression,enhancing the expression of neurotrophic factors and modulating neurotransmission.In this review article,we focus on the current knowledge about the molecular mechanisms underlying environmental enrichment neuroprotection in Parkinson’s disease,highlighting its influence on the dopaminergic,cholinergic,glutamatergic and GABAergic systems,as well as the involvement of neurotrophic factors.We describe experimental pre-clinical data showing how environmental enrichment can act as a modulator in a neurochemical and behavioral context in different animal models of Parkinson’s disease,highlighting the potential of environmental enrichment as an additional strategy in the management and prevention of this complex disease.展开更多
Aging is a physiological event dependent on multiple pathways that are linked to lifespan and processes leading to cognitive decline.This process represents the major risk factor for aging-related diseases such as Alz...Aging is a physiological event dependent on multiple pathways that are linked to lifespan and processes leading to cognitive decline.This process represents the major risk factor for aging-related diseases such as Alzheimer’s disease,Parkinson’s disease,and ischemic stroke.The incidence of all these pathologies increases exponentially with age.Research on aging biology has currently focused on elucidating molecular mechanisms leading to the development of those pathologies.Cognitive deficit and neurodegeneration,common features of aging-related pathologies,are related to the alteration of the activity and levels of neurotrophic factors,such as brain-derived neurotrophic factor,nerve growth factor,and glial cell-derived neurotrophic factor.For this reason,treatments that modulate neurotrophin levels have acquired a great deal of interest in preventing neurodegeneration and promoting neural regeneration in several neurological diseases.Those treatments include both the direct administration of neurotrophic factors and the induced expression with viral vectors,neurotrophins’binding with biomaterials or other molecules to increase their bioavailability but also cell-based therapies.Considering neurotrophins’crucial role in aging pathologies,here we discuss the involvement of several neurotrophic factors in the most common brain aging-related diseases and the most recent therapeutic approaches that provide direct and sustained neurotrophic support.展开更多
Neonatal hypoxic-ischemic encephalopathy continues to be a significant cause of death or neurodevelopmental delays despite standard use of therapeutic hypothermia.The use of stem cell transplantation has recently emer...Neonatal hypoxic-ischemic encephalopathy continues to be a significant cause of death or neurodevelopmental delays despite standard use of therapeutic hypothermia.The use of stem cell transplantation has recently emerged as a promising supplemental therapy to further improve the outcomes of infants with hypoxic-ischemic encephalopathy.After the injury,the brain releases several chemical mediators,many of which communicate directly with stem cells to encourage mobilization,migration,cell adhesion and differentiation.This manuscript reviews the biomarkers that are released from the injured brain and their interactions with stem cells,providing insight regarding how their upregulation could improve stem cell therapy by maximizing cell delivery to the injured tissue.展开更多
The trigeminal root entry zone is the zone at which the myelination switches from peripheral Schwann cells to central oligodendrocytes.Its special anatomical and physiological structure renders it susceptible to nerve...The trigeminal root entry zone is the zone at which the myelination switches from peripheral Schwann cells to central oligodendrocytes.Its special anatomical and physiological structure renders it susceptible to nerve injury.The etiology of most primary trigeminal neuralgia is closely related to microvascular compression of the trigeminal root entry zone.This study aimed to develop an efficient in vitro model mimicking the glial environment of trigeminal root entry zone as a tool to investigate the effects of glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor on the structural and functional integrity of trigeminal root entry zone and modulation of cellular interactions.Primary astrocytes and Schwann cells isolated from trigeminal root entry zone of postnatal rats were inoculated into a two-well silicon culture insert to mimic the trigeminal root entry zone microenvironment and treated with glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor.In monoculture,glial cell line-derived neurotrophic factor promoted the migration of Schwann cells,but it did not have effects on the migration of astrocytes.In the co-culture system,glial cell line-derived neurotrophic factor promoted the bidirectional migration of astrocytes and Schwann cells.Brain-derived neurotrophic factor markedly promoted the activation and migration of astrocytes.However,in the co-culture system,brain-derived neurotrophic factor inhibited the migration of astrocytes and Schwann cells to a certain degree.These findings suggest that glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor are involved in the regulation of the astrocyte-Schwann cell interaction in the co-culture system derived from the trigeminal root entry zone.This system can be used as a cell model to study the mechanism of glial dysregulation associated with trigeminal nerve injury and possible therapeutic interventions.展开更多
Dental pulp stem cells(DPSCs) secrete neurotrophic factors which may play an important therapeutic role in neural development, maintenance and repair. To test this hypothesis, DPSCs-conditioned medium(DPSCs-CM) was co...Dental pulp stem cells(DPSCs) secrete neurotrophic factors which may play an important therapeutic role in neural development, maintenance and repair. To test this hypothesis, DPSCs-conditioned medium(DPSCs-CM) was collected from 72 hours serum-free DPSCs cultures. The impact of DPSCs-derived factors on PC12 survival, growth, migration and differentiation was investigated. PC12 cells were treated with nerve growth factor(NGF), DPSCs-CM or co-cultured with DPSCs using Transwell inserts for 8 days. The number of surviving cells with neurite outgrowths and the length of neurites were measured by image analysis. Immunocytochemical staining was used to evaluate the expression of neuronal markers NeuN, microtubule associated protein 2(MAP-2) and cytoskeletal marker βIII-tubulin. Gene expression levels of axonal growth-associated protein 43 and synaptic protein Synapsin-I, NeuN, MAP-2 and βIII-tubulin were analysed by quantitative polymerase chain reaction(qRT-PCR). DPSCs-CM was analysed for the neurotrophic factors(NGF, brain-derived neurotrophic factor [BDNF], neurotrophin-3, and glial cell-derived neurotrophic factor [GDNF]) by specific ELISAs. Specific neutralizing antibodies against the detected neurotrophic factors were used to study their exact role on PC12 neuronal survival and neurite outgrowth extension. DPSCs-CM significantly promoted cell survival and induced the neurite outgrowth confirmed by NeuN, MAP-2 and βIII-tubulin immunostaining. Furthermore, DPSCsCM was significantly more effective in stimulating PC12 neurite outgrowths than live DPSCs/PC12 co-cultures over the time studied. The morphology of induced PC12 cells in DPSCs-CM was similar to NGF positive controls;however, DPSCs-CM stimulation of cell survival was significantly higher than what was seen in NGF-treated cultures. The number of surviving PC12 cells treated with DPSCs-CM was markedly reduced by the addition of anti-GDNF, whilst PC12 neurite outgrowth was significantly attenuated by anti-NGF, anti-GDNF and anti-BDNF antibodies. These findi展开更多
Glial cell line-derived neurotrophic factor(GDNF),a disease-modifying drug for Parkinson’s disease(PD)is in Phase 2 clinical trials(EudraCT number:2011-003866-34),however it is administered by direct intrastriatal de...Glial cell line-derived neurotrophic factor(GDNF),a disease-modifying drug for Parkinson’s disease(PD)is in Phase 2 clinical trials(EudraCT number:2011-003866-34),however it is administered by direct intrastriatal delivery via stereotaxy,which is accompanied with intracranial infection,brain tissue damage,and other complications.In addition,because of complex administration routes,clinical trials of GDNF have yielded contrary results,largely due to differences in dose and concentration brought by intracranial device.Herein,a small molecular agonist SC79 was screened to open blood-brain barrier(BBB)and promote GDNF liposomes to get into brain.SC79 reversibly reduces the expression of claudin-5,one of dominant tight junctions of BBB.Animal study showed SC79 promoted liposomes to enter into brain parenchyma 2.43 times more than that of the control.Motor deficits of PD mice receiving SC79 and brain-targeted GDNF liposomes were recovered by 36.70%and tyrosine hydroxylase positive neurons in striatum were restored by 39.90%.Our combination therapy effectively avoids the side effects such as secondary infection and uneven delivery caused by intracranial injection,improving patients’compliance and providing valuable research ideas for the clinic.展开更多
Neovascularization and angiogenesis in the brain are important physiological processes for normal brain development and repair/regeneration following insults. Integrins are cell surface adhesion receptors mediating im...Neovascularization and angiogenesis in the brain are important physiological processes for normal brain development and repair/regeneration following insults. Integrins are cell surface adhesion receptors mediating important function of cells such as survival, growth and development during tissue organization, differentiation and organogenesis. In this study, we used an integrin-binding array platform to identify the important types of integrins and their binding peptides that facilitate adhesion, growth, development, and vascular-like network formation of rat primary brain microvascular endothelial cells. Brain microvascular endothelial cells were isolated from rat brain on post-natal day 7. Cells were cultured in a custom-designed integrin array system containing short synthetic peptides binding to 16 types of integrins commonly expressed on cells in vertebrates. After 7 days of culture, the brain microvascular endothelial cells were processed for immunostaining with markers for endothelial cells including von Willibrand factor and platelet endothelial cell adhesion molecule. 5-Bromo-2′-dexoyuridine was added to the culture at 48 hours prior to fixation to assess cell proliferation. Among 16 integrins tested, we found that α5β1, αvβ5 and αvβ8 greatly promoted proliferation of endothelial cells in culture. To investigate the effect of integrin-binding peptides in promoting neovascularization and angiogenesis, the binding peptides to the above three types of integrins were immobilized to our custom-designed hydrogel in three-dimensional(3 D) culture of brain microvascular endothelial cells with the addition of vascular endothelial growth factor. Following a 7-day 3 D culture, the culture was fixed and processed for double labeling of phalloidin with von Willibrand factor or platelet endothelial cell adhesion molecule and assessed under confocal microscopy. In the 3 D culture in hydrogels conjugated with the integrin-binding peptide, brain microvascular endothelial cells formed interconnected vascular-like展开更多
Micro RNA-491-5 p(miR-491-5 p) plays an important role in regulating cell proliferation and migration;however,the effect of miR-491-5 p on neovascularization after traumatic brain injury remains poorly understood.In t...Micro RNA-491-5 p(miR-491-5 p) plays an important role in regulating cell proliferation and migration;however,the effect of miR-491-5 p on neovascularization after traumatic brain injury remains poorly understood.In this study,a controlled cortical injury model in C57 BL/6 mice and an oxygen-glucose deprivation model in microvascular endothelial cells derived from mouse brain were established to simulate traumatic brain injury in vivo and in vitro,respectively.In the in vivo model,quantitative real-time-polymerase chain reaction results showed that the expression of miR-491-5 p increased or decreased following the intracerebroventricular injection of an miR-491-5 p agomir or antagomir,respectively,and the expression of miR-491-5 p decreased slightly after traumatic brain injury.To detect the neuroprotective effects of miR-491-p,neurological severity scores,Morris water maze test,laser speckle techniques,and immunofluorescence staining were assessed,and the results revealed that miR-491-5 p downregulation alleviated neurological dysfunction,promoted the recovery of regional cerebral blood flow,increased the number of lectin-stained microvessels,and increased the survival of neurons after traumatic brain injury.During the in vitro experiments,the potential mechanism of miR-491-5 p on neovascularization was explored through quantitative real-time-polymerase chain reaction,which showed that miR-491-5 p expression increased or decreased in brain microvascular endothelial cells after transfection with an miR-491-5 p mimic or inhibitor,respectively.Dual-luciferase reporter and western blot assays verified that metallothionein-2 was a target gene for miR-491-5 p.Cell counting kit 8(CCK-8) assay,flow cytometry,and 2′,7′-dichlorofluorescein diacetate(DCFH-DA) assay results confirmed that the downregulation of miR-491-5 p increased brain microvascular endothelial cell viability,reduced cell apoptosis,and alleviated oxidative stress under oxygen-glucose deprivation conditions.Cell scratch assay,Transwell assay,tube forma展开更多
Brain(leptomeningeal) metastasis is one of the most common and severe complications of lung cancer. This article interprets expert consensus on the treatment advice for brain(leptomeningeal) metastasis of lung cancer,...Brain(leptomeningeal) metastasis is one of the most common and severe complications of lung cancer. This article interprets expert consensus on the treatment advice for brain(leptomeningeal) metastasis of lung cancer, expounding on its epidemiology, diagnostic standards, efficacy assessment, treatment advice, and other aspects.展开更多
The transplantation of human umbilical cord mesenchymal stem cells(hUC-MSCs)can promote hypoxic-ischemic brain damage(HIBD)nerve repair,but finding suitable seed cells to optimize transplantation and improve treatment...The transplantation of human umbilical cord mesenchymal stem cells(hUC-MSCs)can promote hypoxic-ischemic brain damage(HIBD)nerve repair,but finding suitable seed cells to optimize transplantation and improve treatment efficiency is an urgent problem to be solved.In this study,we induced hUC-MSCs into dedifferentiated hUC-MSCs(De-hUC-MSCs),and the morphology,stem cell surface markers,proliferation and tri-directional differentiation ability of the De-hUC-MSCs and hUC-MSCs were detected.A whole-gene chip was utilized for genome cluster,gene ontology and KEGG pathway analyses of differentially expressed genes.De-hUC-MSCs were transplanted into HIBD rats,and behavioral experiments and immunofluorescence assays were used to assess the therapeutic effect.A lentivirus vector for human stromal cell-derived factor-1(hSDF-1a)was constructed,and the role of hSDF-1a in the neuroprotective effect and mechanism of De-hUC-MSCs was verified.De-hUC-MSCs displayed similar cell morphology,stem cell surface marker expression,cell proliferation and even three-dimensional differentiation ability as hUC-MSCs but exhibited greater treatment potential in vivo.The reprogramming mechanism of hSDF-1a participated in the dedifferentiation process.By successfully constructing a stable hSDF-1a cell line,we found that De-hUC-MSCs might participate in nerve repair through the hSDF-1a/CXCR4/PI3K/Akt pathway.De-hUC-MSCs reprogramming of endogenous hSDF-1a expression may mediate the hSDF-1a/CXCR4/PI3K/Akt pathway involved in nerve repair in HIBD rats.展开更多
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.
文摘Background: Spinal cord injury (SCI) is a worldwide medical concern. This study aimed to elucidate the mechanism underlying protective effect of hyperbaric oxygen (HBO) against SCI-induced neurologic defects in rats via exploring the stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor 4 (CXCR4) axis and expression of brain-derived neurotrophic factor (BDNF). Methods: An acute SCI rat model was established in Sprague-Dawley rats using the Allen method. Sixty rats were divided into four groups (w = 15 in each group): sham-operated, SCI, SCI treated with HBO (SCI + HBO), and SCI treated with both HBO and AMD3100 (an antagonist of CXCR4;SCI + HBO + AMD) groups. The rats were treated with HBO twice a day for 3 days and thereafter once a day after the surgery for up to 28 days. Following the surgery, neurologic assessments were performed with the Basso-Bettie-Bresnahan (BBB) scoring system on postoperative day (POD) 7, 14, 21, and 28. Spinal cord tissues were harvested to assess the expression of SDF-1, CXCR4, and BDNF at mRNA and protein levels, using quantitative real-time polymerase chain reaction, Western blot analysis, and histopathologic analysis. Results: HBO treatment recovered SCI-induced descent of BBB scores on POD 14,(1.25±0.75 vs. 1.03 ±0.66, P< 0.05), 21 (5.27± 0.89 vs. 2.56± 1.24, P< 0.05), and 28 (11.35±0.56 vs. 4.23± 1.20, P<0.05) compared with the SCI group. Significant differences were found in the mRNA levels of SDF-1 (mRNA: day 21, SCI + HBO vs. SCI + HBO + AMD, 2.89± 1.60 vs. 1.56±0.98, P<0.05), CXCR4 (mRNA: day 7, SCI + HBO vs. SCI, 2.99± 1.60 vs. 1.31 ±0.98, P<0.05;day 14, SCI + HBO vs. SCI + HBO + AMD, 4.18± 1.60 vs. 0.80±0.34, P<0.05;day 21, SCI + HBO vs. SCI, 2.10±1.01 vs.1.15±0.03, P<0.05), and BDNF (mRNA: day 7, SCI + HBO vs. SCI, 3.04±0.41 vs. 2.75±0.31, P<0.05;day 14, SCI + HBO vs. SCI, 3.88± 1.59 vs. 1.11 ±0.40, P<0.05), indicating the involvement of SDF-1/CXCR4 axis in the protective effect of HBO. Conclusions: HBO might promote the recovery of neurologic func
基金Supported by the Social Development Project of Jiangsu Science and Technology Department,No.BE2015721。
文摘Neurodegenerative diseases,including Alzheimer’s disease,Parkinson’s disease,Huntington’s disease and amyotrophic lateral sclerosis,are a group of incurable neurological disorders,characterized by the chronic progressive loss of different neuronal subtypes.However,despite its increasing prevalence among the everincreasing aging population,little progress has been made in the coincident immense efforts towards development of therapeutic agents.Research interest has recently turned towards stem cells including stem cells-derived exosomes,neurotrophic factors,and their combination as potential therapeutic agents in neurodegenerative diseases.In this review,we summarize the progress in therapeutic strategies based on stem cells combined with neurotrophic factors and mesenchymal stem cells-derived exosomes for neurodegenerative diseases,with an emphasis on the combination therapy.
文摘Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postural instability,as a result of the progressive loss of nigrostriatal dopaminergic neurons.In addition to this neuronal cell loss,Parkinson’s disease is characterized by the accumulation of intracellular protein aggregates,Lewy bodies and Lewy neurites,composed primarily of the proteinα-synuclein.Although it was first described almost 200 years ago,there are no disease-modifying drugs to treat patients with Parkinson’s disease.In addition to conventional therapies,non-pharmacological treatment strategies are under investigation in patients and animal models of neurodegenerative disorders.Among such strategies,environmental enrichment,comprising physical exercise,cognitive stimulus,and social interactions,has been assessed in preclinical models of Parkinson’s disease.Environmental enrichment can cause structural and functional changes in the brain and promote neurogenesis and dendritic growth by modifying gene expression,enhancing the expression of neurotrophic factors and modulating neurotransmission.In this review article,we focus on the current knowledge about the molecular mechanisms underlying environmental enrichment neuroprotection in Parkinson’s disease,highlighting its influence on the dopaminergic,cholinergic,glutamatergic and GABAergic systems,as well as the involvement of neurotrophic factors.We describe experimental pre-clinical data showing how environmental enrichment can act as a modulator in a neurochemical and behavioral context in different animal models of Parkinson’s disease,highlighting the potential of environmental enrichment as an additional strategy in the management and prevention of this complex disease.
文摘Aging is a physiological event dependent on multiple pathways that are linked to lifespan and processes leading to cognitive decline.This process represents the major risk factor for aging-related diseases such as Alzheimer’s disease,Parkinson’s disease,and ischemic stroke.The incidence of all these pathologies increases exponentially with age.Research on aging biology has currently focused on elucidating molecular mechanisms leading to the development of those pathologies.Cognitive deficit and neurodegeneration,common features of aging-related pathologies,are related to the alteration of the activity and levels of neurotrophic factors,such as brain-derived neurotrophic factor,nerve growth factor,and glial cell-derived neurotrophic factor.For this reason,treatments that modulate neurotrophin levels have acquired a great deal of interest in preventing neurodegeneration and promoting neural regeneration in several neurological diseases.Those treatments include both the direct administration of neurotrophic factors and the induced expression with viral vectors,neurotrophins’binding with biomaterials or other molecules to increase their bioavailability but also cell-based therapies.Considering neurotrophins’crucial role in aging pathologies,here we discuss the involvement of several neurotrophic factors in the most common brain aging-related diseases and the most recent therapeutic approaches that provide direct and sustained neurotrophic support.
文摘Neonatal hypoxic-ischemic encephalopathy continues to be a significant cause of death or neurodevelopmental delays despite standard use of therapeutic hypothermia.The use of stem cell transplantation has recently emerged as a promising supplemental therapy to further improve the outcomes of infants with hypoxic-ischemic encephalopathy.After the injury,the brain releases several chemical mediators,many of which communicate directly with stem cells to encourage mobilization,migration,cell adhesion and differentiation.This manuscript reviews the biomarkers that are released from the injured brain and their interactions with stem cells,providing insight regarding how their upregulation could improve stem cell therapy by maximizing cell delivery to the injured tissue.
基金supported by the National Natural Sclence Foundation of China in 2021No.82171213+1 种基金the Natural Science Foundation of Fujian Province in 2019No.2019J01289 (both to DSL)
文摘The trigeminal root entry zone is the zone at which the myelination switches from peripheral Schwann cells to central oligodendrocytes.Its special anatomical and physiological structure renders it susceptible to nerve injury.The etiology of most primary trigeminal neuralgia is closely related to microvascular compression of the trigeminal root entry zone.This study aimed to develop an efficient in vitro model mimicking the glial environment of trigeminal root entry zone as a tool to investigate the effects of glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor on the structural and functional integrity of trigeminal root entry zone and modulation of cellular interactions.Primary astrocytes and Schwann cells isolated from trigeminal root entry zone of postnatal rats were inoculated into a two-well silicon culture insert to mimic the trigeminal root entry zone microenvironment and treated with glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor.In monoculture,glial cell line-derived neurotrophic factor promoted the migration of Schwann cells,but it did not have effects on the migration of astrocytes.In the co-culture system,glial cell line-derived neurotrophic factor promoted the bidirectional migration of astrocytes and Schwann cells.Brain-derived neurotrophic factor markedly promoted the activation and migration of astrocytes.However,in the co-culture system,brain-derived neurotrophic factor inhibited the migration of astrocytes and Schwann cells to a certain degree.These findings suggest that glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor are involved in the regulation of the astrocyte-Schwann cell interaction in the co-culture system derived from the trigeminal root entry zone.This system can be used as a cell model to study the mechanism of glial dysregulation associated with trigeminal nerve injury and possible therapeutic interventions.
基金funded by Egyptian Cultural and Educational Bureau in London,Egyptian mission sector and ministry of higher education in Egypt(grant No.GAM2649)。
文摘Dental pulp stem cells(DPSCs) secrete neurotrophic factors which may play an important therapeutic role in neural development, maintenance and repair. To test this hypothesis, DPSCs-conditioned medium(DPSCs-CM) was collected from 72 hours serum-free DPSCs cultures. The impact of DPSCs-derived factors on PC12 survival, growth, migration and differentiation was investigated. PC12 cells were treated with nerve growth factor(NGF), DPSCs-CM or co-cultured with DPSCs using Transwell inserts for 8 days. The number of surviving cells with neurite outgrowths and the length of neurites were measured by image analysis. Immunocytochemical staining was used to evaluate the expression of neuronal markers NeuN, microtubule associated protein 2(MAP-2) and cytoskeletal marker βIII-tubulin. Gene expression levels of axonal growth-associated protein 43 and synaptic protein Synapsin-I, NeuN, MAP-2 and βIII-tubulin were analysed by quantitative polymerase chain reaction(qRT-PCR). DPSCs-CM was analysed for the neurotrophic factors(NGF, brain-derived neurotrophic factor [BDNF], neurotrophin-3, and glial cell-derived neurotrophic factor [GDNF]) by specific ELISAs. Specific neutralizing antibodies against the detected neurotrophic factors were used to study their exact role on PC12 neuronal survival and neurite outgrowth extension. DPSCs-CM significantly promoted cell survival and induced the neurite outgrowth confirmed by NeuN, MAP-2 and βIII-tubulin immunostaining. Furthermore, DPSCsCM was significantly more effective in stimulating PC12 neurite outgrowths than live DPSCs/PC12 co-cultures over the time studied. The morphology of induced PC12 cells in DPSCs-CM was similar to NGF positive controls;however, DPSCs-CM stimulation of cell survival was significantly higher than what was seen in NGF-treated cultures. The number of surviving PC12 cells treated with DPSCs-CM was markedly reduced by the addition of anti-GDNF, whilst PC12 neurite outgrowth was significantly attenuated by anti-NGF, anti-GDNF and anti-BDNF antibodies. These findi
基金supported by the National Natural Science Foundation of China(No.81973267)Natural Science Foundation of Zhejiang Province(No.LD19H300001).
文摘Glial cell line-derived neurotrophic factor(GDNF),a disease-modifying drug for Parkinson’s disease(PD)is in Phase 2 clinical trials(EudraCT number:2011-003866-34),however it is administered by direct intrastriatal delivery via stereotaxy,which is accompanied with intracranial infection,brain tissue damage,and other complications.In addition,because of complex administration routes,clinical trials of GDNF have yielded contrary results,largely due to differences in dose and concentration brought by intracranial device.Herein,a small molecular agonist SC79 was screened to open blood-brain barrier(BBB)and promote GDNF liposomes to get into brain.SC79 reversibly reduces the expression of claudin-5,one of dominant tight junctions of BBB.Animal study showed SC79 promoted liposomes to enter into brain parenchyma 2.43 times more than that of the control.Motor deficits of PD mice receiving SC79 and brain-targeted GDNF liposomes were recovered by 36.70%and tyrosine hydroxylase positive neurons in striatum were restored by 39.90%.Our combination therapy effectively avoids the side effects such as secondary infection and uneven delivery caused by intracranial injection,improving patients’compliance and providing valuable research ideas for the clinic.
基金supported by NIH grant RO1 NS093985 (to DS, NZ, XW) and RO1 NS101955 (to DS)the VCU Microscopy Facility,supported,in part,by funding from NIH-NCI Cancer Center Support Grant P30 CA016059。
文摘Neovascularization and angiogenesis in the brain are important physiological processes for normal brain development and repair/regeneration following insults. Integrins are cell surface adhesion receptors mediating important function of cells such as survival, growth and development during tissue organization, differentiation and organogenesis. In this study, we used an integrin-binding array platform to identify the important types of integrins and their binding peptides that facilitate adhesion, growth, development, and vascular-like network formation of rat primary brain microvascular endothelial cells. Brain microvascular endothelial cells were isolated from rat brain on post-natal day 7. Cells were cultured in a custom-designed integrin array system containing short synthetic peptides binding to 16 types of integrins commonly expressed on cells in vertebrates. After 7 days of culture, the brain microvascular endothelial cells were processed for immunostaining with markers for endothelial cells including von Willibrand factor and platelet endothelial cell adhesion molecule. 5-Bromo-2′-dexoyuridine was added to the culture at 48 hours prior to fixation to assess cell proliferation. Among 16 integrins tested, we found that α5β1, αvβ5 and αvβ8 greatly promoted proliferation of endothelial cells in culture. To investigate the effect of integrin-binding peptides in promoting neovascularization and angiogenesis, the binding peptides to the above three types of integrins were immobilized to our custom-designed hydrogel in three-dimensional(3 D) culture of brain microvascular endothelial cells with the addition of vascular endothelial growth factor. Following a 7-day 3 D culture, the culture was fixed and processed for double labeling of phalloidin with von Willibrand factor or platelet endothelial cell adhesion molecule and assessed under confocal microscopy. In the 3 D culture in hydrogels conjugated with the integrin-binding peptide, brain microvascular endothelial cells formed interconnected vascular-like
基金supported by the National Natural Science Foundation of China,Nos.82071397 (to XCS),82071332 (to ZDG)the Youth Fund of the National Natural Science Foundation of China,No.81801230 (to JJZ)the Excellent Scientific Research Talents Fund of the First Affiliated Hospital of Chongqing Medical University,China (to JJZ)。
文摘Micro RNA-491-5 p(miR-491-5 p) plays an important role in regulating cell proliferation and migration;however,the effect of miR-491-5 p on neovascularization after traumatic brain injury remains poorly understood.In this study,a controlled cortical injury model in C57 BL/6 mice and an oxygen-glucose deprivation model in microvascular endothelial cells derived from mouse brain were established to simulate traumatic brain injury in vivo and in vitro,respectively.In the in vivo model,quantitative real-time-polymerase chain reaction results showed that the expression of miR-491-5 p increased or decreased following the intracerebroventricular injection of an miR-491-5 p agomir or antagomir,respectively,and the expression of miR-491-5 p decreased slightly after traumatic brain injury.To detect the neuroprotective effects of miR-491-p,neurological severity scores,Morris water maze test,laser speckle techniques,and immunofluorescence staining were assessed,and the results revealed that miR-491-5 p downregulation alleviated neurological dysfunction,promoted the recovery of regional cerebral blood flow,increased the number of lectin-stained microvessels,and increased the survival of neurons after traumatic brain injury.During the in vitro experiments,the potential mechanism of miR-491-5 p on neovascularization was explored through quantitative real-time-polymerase chain reaction,which showed that miR-491-5 p expression increased or decreased in brain microvascular endothelial cells after transfection with an miR-491-5 p mimic or inhibitor,respectively.Dual-luciferase reporter and western blot assays verified that metallothionein-2 was a target gene for miR-491-5 p.Cell counting kit 8(CCK-8) assay,flow cytometry,and 2′,7′-dichlorofluorescein diacetate(DCFH-DA) assay results confirmed that the downregulation of miR-491-5 p increased brain microvascular endothelial cell viability,reduced cell apoptosis,and alleviated oxidative stress under oxygen-glucose deprivation conditions.Cell scratch assay,Transwell assay,tube forma
文摘Brain(leptomeningeal) metastasis is one of the most common and severe complications of lung cancer. This article interprets expert consensus on the treatment advice for brain(leptomeningeal) metastasis of lung cancer, expounding on its epidemiology, diagnostic standards, efficacy assessment, treatment advice, and other aspects.
基金supported by the National Natural Science of China(grant number 81601973)。
文摘The transplantation of human umbilical cord mesenchymal stem cells(hUC-MSCs)can promote hypoxic-ischemic brain damage(HIBD)nerve repair,but finding suitable seed cells to optimize transplantation and improve treatment efficiency is an urgent problem to be solved.In this study,we induced hUC-MSCs into dedifferentiated hUC-MSCs(De-hUC-MSCs),and the morphology,stem cell surface markers,proliferation and tri-directional differentiation ability of the De-hUC-MSCs and hUC-MSCs were detected.A whole-gene chip was utilized for genome cluster,gene ontology and KEGG pathway analyses of differentially expressed genes.De-hUC-MSCs were transplanted into HIBD rats,and behavioral experiments and immunofluorescence assays were used to assess the therapeutic effect.A lentivirus vector for human stromal cell-derived factor-1(hSDF-1a)was constructed,and the role of hSDF-1a in the neuroprotective effect and mechanism of De-hUC-MSCs was verified.De-hUC-MSCs displayed similar cell morphology,stem cell surface marker expression,cell proliferation and even three-dimensional differentiation ability as hUC-MSCs but exhibited greater treatment potential in vivo.The reprogramming mechanism of hSDF-1a participated in the dedifferentiation process.By successfully constructing a stable hSDF-1a cell line,we found that De-hUC-MSCs might participate in nerve repair through the hSDF-1a/CXCR4/PI3K/Akt pathway.De-hUC-MSCs reprogramming of endogenous hSDF-1a expression may mediate the hSDF-1a/CXCR4/PI3K/Akt pathway involved in nerve repair in HIBD rats.
