Previous studies have reported age-specific pathological and functional outcomes in young and aged patients suffering spinal cord injury,but the mechanisms remain poorly understood. In this study, we examined mice wit...Previous studies have reported age-specific pathological and functional outcomes in young and aged patients suffering spinal cord injury,but the mechanisms remain poorly understood. In this study, we examined mice with spinal cord injury. Gene expression profiles from the Gene Expression Omnibus database （accession number GSE93561） were used, including spinal cord samples from 3 young injured mice （2–3-months old, induced by Impactor at Th9 level） and 3 control mice （2–3-months old, no treatment）, as well as 2 aged injured mice （15–18-months old, induced by Impactor at Th9 level） and 2 control mice （15–18-months old, no treatment）. Differentially expressed genes （DEGs） in spinal cord tissue from injured and control mice were identified using the Linear Models for Microarray data method,with a threshold of adjusted P 〈 0.05 and ｜logFC（fold change）｜ 〉 1.5. Protein–protein interaction networks were constructed using data from the STRING database, followed by module analysis by Cytoscape software to screen crucial genes. Kyoto encyclopedia of genes and genomes pathway and Gene Ontology enrichment analyses were performed to investigate the underlying functions of DEGs using Database for Annotation, Visualization and Integrated Discovery. Consequently, 1,604 and 1,153 DEGs were identified between injured and normal control mice in spinal cord tissue of aged and young mice, respectively. Furthermore, a Venn diagram showed that 960 DEGs were shared among aged and young mice, while 644 and 193 DEGs were specific to aged and young mice, respectively. Functional enrichment indicates that shared DEGs are involved in osteoclast differentiation, extracellular matrix–receptor interaction, nuclear factor-kappa B signaling pathway, and focal adhesion. Unique genes for aged and young injured groups were involved in the cell cycle （upregulation of PLK1） and complement （upregulation of C3） activation, respectively. These findings were confirmed by functional analysis of genes in modules （common, 4; aged, 2; young, 1） screened from protein–protein interaction networks. Accordingly, cell cycle and complement inhibitors may be specific treatments for spinal cord injury in aged and young mice, respectively.展开更多
After spinal cord injury, dysregulated miRNAs appear and can participate in inflammatory responses, as well as the inhibition of apoptosis and axon regeneration through multiple pathways. However, the functions of miR...After spinal cord injury, dysregulated miRNAs appear and can participate in inflammatory responses, as well as the inhibition of apoptosis and axon regeneration through multiple pathways. However, the functions of miRNAs in spinal cord ischemia-reperfusion injury progression remain unclear. miRCURY LNATM Arrays were used to analyze miRNA expression profiles of rats after 90 minutes of ischemia followed by reperfusion for 24 and 48 hours. Furthermore, subsequent construction of aberrantly expressed miRNA regulatory patterns involved cell survival, proliferation, and apoptosis. Remarkably, the mitogen-activated protein kinase(MAPK) signaling pathway was the most significantly enriched pathway among 24-and 48-hour groups. Bioinformatics analysis and quantitative reverse transcription polymerase chain reaction confirmed the persistent overexpression of miR-22-3 p in both groups. These results suggest that the aberrant miRNA regulatory network is possibly regulated MAPK signaling and continuously affects the physiological and biochemical status of cells, thus participating in the regulation of spinal cord ischemia-reperfusion injury. As such, miR-22-3 p may play sustained regulatory roles in spinal cord ischemia-reperfusion injury. All experimental procedures were approved by the Animal Ethics Committee of Jilin University, China [approval No. 2020(Research) 01].展开更多
Brain plasticity, including anatomical changes and functional reorganization, is the physiological basis of functional recovery after spinal cord injury（SCI）. The correlation between brain anatomical changes and fun...Brain plasticity, including anatomical changes and functional reorganization, is the physiological basis of functional recovery after spinal cord injury（SCI）. The correlation between brain anatomical changes and functional reorganization after SCI is unclear. This study aimed to explore whether alterations of cortical structure and network function are concomitant in sensorimotor areas after incomplete SCI. Eighteen patients with incomplete SCI（mean age 40.94 ± 14.10 years old; male：female, 7：11） and 18 healthy subjects（37.33 ± 11.79 years old; male：female, 7：11） were studied by resting state functional magnetic resonance imaging. Gray matter volume（GMV） and functional connectivity were used to evaluate cortical structure and network function, respectively. There was no significant alteration of GMV in sensorimotor areas in patients with incomplete SCI compared with healthy subjects. Intra-hemispheric functional connectivity between left primary somatosensory cortex（BA1） and left primary motor cortex（BA4）, and left BA1 and left somatosensory association cortex（BA5） was decreased, as well as inter-hemispheric functional connectivity between left BA1 and right BA4, left BA1 and right BA5, and left BA4 and right BA5 in patients with SCI. Functional connectivity between both BA4 areas was also decreased. The decreased functional connectivity between the left BA1 and the right BA4 positively correlated with American Spinal Injury Association sensory score in SCI patients. The results indicate that alterations of cortical anatomical structure and network functional connectivity in sensorimotor areas were non-concomitant in patients with incomplete SCI, indicating the network functional changes in sensorimotor areas may not be dependent on anatomic structure. The strength of functional connectivity within sensorimotor areas could serve as a potential imaging biomarker for assessment and prediction of sensory function in patients with incomplete SCI. This trial was registered with the Chinese Clinical Trial Registry（registration number： Chi CTR-ROC-17013566）.展开更多
The mechanism underlying neurogenesis during embryonic spinal cord development involves a specific ligand/receptor interaction,which may be help guide neuroengineering to boost stem cell-based neural regeneration for ...The mechanism underlying neurogenesis during embryonic spinal cord development involves a specific ligand/receptor interaction,which may be help guide neuroengineering to boost stem cell-based neural regeneration for the structural and functional repair of spinal cord injury.Herein,we hypothesized that supplying spinal cord defects with an exogenous neural network in the NT-3/fibroin-coated gelatin sponge(NF-GS)scaffold might improve tissue repair efficacy.To test this,we engineered tropomyosin receptor kinase C(TrkC)-modified neural stem cell(NSC)-derived neural network tissue with robust viability within an NF-GS scaffold.When NSCs were genetically modified to overexpress TrkC,the NT-3 receptor,a functional neuronal population dominated the neural network tissue.The pro-regenerative niche allowed the long-term survival and phenotypic maintenance of the donor neural network tissue for up to 8 weeks in the injured spinal cord.Additionally,host nerve fibers regenerated into the graft,making synaptic connections with the donor neurons.Accordingly,motor function recovery was significantly improved in rats with spinal cord injury(SCI)that received TrkC-modified NSC-derived neural network tissue transplantation.Together,the results suggested that transplantation of the neural network tissue formed in the 3D bioactive scaffold may represent a valuable approach to study and develop therapies for SCI.展开更多
Induced pluripotent stem cells(iPSCs)can be personalized and differentiated into neural stem cells(NSCs),thereby effectively providing a source of transplanted cells for spinal cord injury(SCI).To further improve the ...Induced pluripotent stem cells(iPSCs)can be personalized and differentiated into neural stem cells(NSCs),thereby effectively providing a source of transplanted cells for spinal cord injury(SCI).To further improve the repair efficiency of SCI,we designed a functional neural network tissue based on TrkC-modified iPSC-derived NSCs and a CBD-NT3-modified linear-ordered collagen scaffold(LOCS).We confirmed that transplantation of this tissue regenerated neurons and synapses,improved the microenvironment of the injured area,enhanced remodeling of the extracellular matrix,and promoted functional recovery of the hind limbs in a rat SCI model with complete transection.RNA sequencing and metabolomic analyses also confirmed the repair effect of this tissue from multiple perspectives and revealed its potential mechanism for treating SCI.Together,we constructed a functional neural network tissue using human iPSCs-derived NSCs as seed cells based on the interaction of receptors and ligands for the first time.This tissue can effectively improve the therapeutic effect of SCI,thus confirming the feasibility of human iPSCs-derived NSCs and LOCS for SCI repair and providing a valuable direction for SCI research.展开更多
The present study aimed to explore the potential of the sodium hyaluronate-CNTF (ciliary neurotrophic factor) scaffold in activating endogenous neurogenesis and facilitating neural network re-formation after the adult...The present study aimed to explore the potential of the sodium hyaluronate-CNTF (ciliary neurotrophic factor) scaffold in activating endogenous neurogenesis and facilitating neural network re-formation after the adult rat spinal cord injury (SCI). After completely cutting and removing a 5-mm adult rat T8 segment, a sodium hyaluronate-CNTF scaffold was implanted into the lesion area. Dil tracing and immunofluorescence staining were used to observe the proliferation, differentiation and integration of neural stem cells (NSCs) after SCI. A planar multielectrode dish system (MED64) was used to test the electrophysiological characteristics of the regenerated neural network in the lesioned area. Electrophysiology and behavior evaluation were used to evaluate functional recovery of paraplegic rat hindlimbs. The Dil tracing and immunofluorescence results suggest that the sodium hyaluronate-CNTF scaffold could activate the NSCs originating from the spinal cord ependymal, and facilitate their migration to the lesion area and differentiation into mature neurons, which were capable of forming synaptic contact and receiving glutamatergic excitatory synaptic input. The MED64 results suggest that functional synapsis could be established among regenerated neurons as well as between regenerated neurons and the host tissue, which has been evidenced to be glutamatergic excitatory synapsis. The electrophysiology and behavior evaluation results indicate that the paraplegic rats’ sensory and motor functions were recovered in some degree. Collectively, this study may shed light on paraplegia treatment in clinics.展开更多
基金supported by the National Science Fund for Distinguished Young Scientists of China,No.81601052
文摘Previous studies have reported age-specific pathological and functional outcomes in young and aged patients suffering spinal cord injury,but the mechanisms remain poorly understood. In this study, we examined mice with spinal cord injury. Gene expression profiles from the Gene Expression Omnibus database （accession number GSE93561） were used, including spinal cord samples from 3 young injured mice （2–3-months old, induced by Impactor at Th9 level） and 3 control mice （2–3-months old, no treatment）, as well as 2 aged injured mice （15–18-months old, induced by Impactor at Th9 level） and 2 control mice （15–18-months old, no treatment）. Differentially expressed genes （DEGs） in spinal cord tissue from injured and control mice were identified using the Linear Models for Microarray data method,with a threshold of adjusted P 〈 0.05 and ｜logFC（fold change）｜ 〉 1.5. Protein–protein interaction networks were constructed using data from the STRING database, followed by module analysis by Cytoscape software to screen crucial genes. Kyoto encyclopedia of genes and genomes pathway and Gene Ontology enrichment analyses were performed to investigate the underlying functions of DEGs using Database for Annotation, Visualization and Integrated Discovery. Consequently, 1,604 and 1,153 DEGs were identified between injured and normal control mice in spinal cord tissue of aged and young mice, respectively. Furthermore, a Venn diagram showed that 960 DEGs were shared among aged and young mice, while 644 and 193 DEGs were specific to aged and young mice, respectively. Functional enrichment indicates that shared DEGs are involved in osteoclast differentiation, extracellular matrix–receptor interaction, nuclear factor-kappa B signaling pathway, and focal adhesion. Unique genes for aged and young injured groups were involved in the cell cycle （upregulation of PLK1） and complement （upregulation of C3） activation, respectively. These findings were confirmed by functional analysis of genes in modules （common, 4; aged, 2; young, 1） screened from protein–protein interaction networks. Accordingly, cell cycle and complement inhibitors may be specific treatments for spinal cord injury in aged and young mice, respectively.
基金supported by the National Natural Science Foundation of China,No.81350013(to XYY)。
文摘After spinal cord injury, dysregulated miRNAs appear and can participate in inflammatory responses, as well as the inhibition of apoptosis and axon regeneration through multiple pathways. However, the functions of miRNAs in spinal cord ischemia-reperfusion injury progression remain unclear. miRCURY LNATM Arrays were used to analyze miRNA expression profiles of rats after 90 minutes of ischemia followed by reperfusion for 24 and 48 hours. Furthermore, subsequent construction of aberrantly expressed miRNA regulatory patterns involved cell survival, proliferation, and apoptosis. Remarkably, the mitogen-activated protein kinase(MAPK) signaling pathway was the most significantly enriched pathway among 24-and 48-hour groups. Bioinformatics analysis and quantitative reverse transcription polymerase chain reaction confirmed the persistent overexpression of miR-22-3 p in both groups. These results suggest that the aberrant miRNA regulatory network is possibly regulated MAPK signaling and continuously affects the physiological and biochemical status of cells, thus participating in the regulation of spinal cord ischemia-reperfusion injury. As such, miR-22-3 p may play sustained regulatory roles in spinal cord ischemia-reperfusion injury. All experimental procedures were approved by the Animal Ethics Committee of Jilin University, China [approval No. 2020(Research) 01].
基金supported by a grant from Tsinghua University Initiative Scientific Research Program,No.2014081266,20131089382the National Natural Science Foundation of China,No.61171002,60372023
文摘Brain plasticity, including anatomical changes and functional reorganization, is the physiological basis of functional recovery after spinal cord injury（SCI）. The correlation between brain anatomical changes and functional reorganization after SCI is unclear. This study aimed to explore whether alterations of cortical structure and network function are concomitant in sensorimotor areas after incomplete SCI. Eighteen patients with incomplete SCI（mean age 40.94 ± 14.10 years old; male：female, 7：11） and 18 healthy subjects（37.33 ± 11.79 years old; male：female, 7：11） were studied by resting state functional magnetic resonance imaging. Gray matter volume（GMV） and functional connectivity were used to evaluate cortical structure and network function, respectively. There was no significant alteration of GMV in sensorimotor areas in patients with incomplete SCI compared with healthy subjects. Intra-hemispheric functional connectivity between left primary somatosensory cortex（BA1） and left primary motor cortex（BA4）, and left BA1 and left somatosensory association cortex（BA5） was decreased, as well as inter-hemispheric functional connectivity between left BA1 and right BA4, left BA1 and right BA5, and left BA4 and right BA5 in patients with SCI. Functional connectivity between both BA4 areas was also decreased. The decreased functional connectivity between the left BA1 and the right BA4 positively correlated with American Spinal Injury Association sensory score in SCI patients. The results indicate that alterations of cortical anatomical structure and network functional connectivity in sensorimotor areas were non-concomitant in patients with incomplete SCI, indicating the network functional changes in sensorimotor areas may not be dependent on anatomic structure. The strength of functional connectivity within sensorimotor areas could serve as a potential imaging biomarker for assessment and prediction of sensory function in patients with incomplete SCI. This trial was registered with the Chinese Clinical Trial Registry（registration number： Chi CTR-ROC-17013566）.
基金the Chinese National Natural Science Foundation of China(81891003)the National Key R&D Program of China(2017YFA0104700)and the 111 Project for Academic Exchange Program(B13037)to Y.S.Zeng+2 种基金the Foundation of Guangdong Province(2017B020210012)to Y.S.Zeng and X.Zengthe Co-innovation Foundation of Guangzhou City(201704020221)to Y.S.Zeng,X.Zeng,and G.Lithe Start-up Foundation of Guangdong Province(Grant No.2018A030310113)to G.Li.
文摘The mechanism underlying neurogenesis during embryonic spinal cord development involves a specific ligand/receptor interaction,which may be help guide neuroengineering to boost stem cell-based neural regeneration for the structural and functional repair of spinal cord injury.Herein,we hypothesized that supplying spinal cord defects with an exogenous neural network in the NT-3/fibroin-coated gelatin sponge(NF-GS)scaffold might improve tissue repair efficacy.To test this,we engineered tropomyosin receptor kinase C(TrkC)-modified neural stem cell(NSC)-derived neural network tissue with robust viability within an NF-GS scaffold.When NSCs were genetically modified to overexpress TrkC,the NT-3 receptor,a functional neuronal population dominated the neural network tissue.The pro-regenerative niche allowed the long-term survival and phenotypic maintenance of the donor neural network tissue for up to 8 weeks in the injured spinal cord.Additionally,host nerve fibers regenerated into the graft,making synaptic connections with the donor neurons.Accordingly,motor function recovery was significantly improved in rats with spinal cord injury(SCI)that received TrkC-modified NSC-derived neural network tissue transplantation.Together,the results suggested that transplantation of the neural network tissue formed in the 3D bioactive scaffold may represent a valuable approach to study and develop therapies for SCI.
基金supported by the National Natural Science Foundation of China(82071399)National Key Research and Development Program of China(2023YFC2412504,2016YFC1101502)Key Research and Development Program of Hunan Province(2021DK2003,2021SK2016).
文摘Induced pluripotent stem cells(iPSCs)can be personalized and differentiated into neural stem cells(NSCs),thereby effectively providing a source of transplanted cells for spinal cord injury(SCI).To further improve the repair efficiency of SCI,we designed a functional neural network tissue based on TrkC-modified iPSC-derived NSCs and a CBD-NT3-modified linear-ordered collagen scaffold(LOCS).We confirmed that transplantation of this tissue regenerated neurons and synapses,improved the microenvironment of the injured area,enhanced remodeling of the extracellular matrix,and promoted functional recovery of the hind limbs in a rat SCI model with complete transection.RNA sequencing and metabolomic analyses also confirmed the repair effect of this tissue from multiple perspectives and revealed its potential mechanism for treating SCI.Together,we constructed a functional neural network tissue using human iPSCs-derived NSCs as seed cells based on the interaction of receptors and ligands for the first time.This tissue can effectively improve the therapeutic effect of SCI,thus confirming the feasibility of human iPSCs-derived NSCs and LOCS for SCI repair and providing a valuable direction for SCI research.
基金supported by the State Key Program of the National Natural Science Foundation of China (31130022,31320103903, 31271037 & 31670988)the International Cooperation in Science and Technology Project of the Ministry of Science and Technology of China (2014DFA30640)+2 种基金the National Ministry of Education Special Fund for Excellent Doctoral Dissertation (201356)the Special Fund for Excellent Doctoral Dissertation of Beijing (20111000601)the Special Funds for Beijing Base Construction & Talent Cultivation (171100002217066)
文摘The present study aimed to explore the potential of the sodium hyaluronate-CNTF (ciliary neurotrophic factor) scaffold in activating endogenous neurogenesis and facilitating neural network re-formation after the adult rat spinal cord injury (SCI). After completely cutting and removing a 5-mm adult rat T8 segment, a sodium hyaluronate-CNTF scaffold was implanted into the lesion area. Dil tracing and immunofluorescence staining were used to observe the proliferation, differentiation and integration of neural stem cells (NSCs) after SCI. A planar multielectrode dish system (MED64) was used to test the electrophysiological characteristics of the regenerated neural network in the lesioned area. Electrophysiology and behavior evaluation were used to evaluate functional recovery of paraplegic rat hindlimbs. The Dil tracing and immunofluorescence results suggest that the sodium hyaluronate-CNTF scaffold could activate the NSCs originating from the spinal cord ependymal, and facilitate their migration to the lesion area and differentiation into mature neurons, which were capable of forming synaptic contact and receiving glutamatergic excitatory synaptic input. The MED64 results suggest that functional synapsis could be established among regenerated neurons as well as between regenerated neurons and the host tissue, which has been evidenced to be glutamatergic excitatory synapsis. The electrophysiology and behavior evaluation results indicate that the paraplegic rats’ sensory and motor functions were recovered in some degree. Collectively, this study may shed light on paraplegia treatment in clinics.
