Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory damage.The expression of the C-C motif chemokine ligand...Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory damage.The expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after injury.Recent studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for treatment.This review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord injury.Additionally,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted drugs.Nevertheless,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.展开更多
Stromal cell-derived factor-1 and its receptor C-X-C chemokine receptor 4(CXCR4) have been shown to regulate neural regeneration after stroke.Howeve r,whether stromal cell-derived factor-1 receptor CXCR7,which is wide...Stromal cell-derived factor-1 and its receptor C-X-C chemokine receptor 4(CXCR4) have been shown to regulate neural regeneration after stroke.Howeve r,whether stromal cell-derived factor-1 receptor CXCR7,which is widely distributed in the develo ping and adult central nervous system,participates in neural regeneration remains poorly unde rstood.In this study,we established rat models of focal cerebral ischemia by injecting endothelin-1 into the cerebral co rtex and striatum.Starting on day 7 after injury,CXCR7-neutralizing antibody was injected into the lateral ventricle using a micro drug delivery system for 6 consecutive days.Our results showed that CXCR7-neutralizing antibody increased the total length and number of sprouting co rticospinal tra ct fibers in rats with cerebral ischemia,increased the expression of vesicular glutamate transporter 1 and growth-related protein 43,marke rs of the denervated spinal cord synapses,and promoted the differentiation and maturation of oligodendrocyte progenitor cells in the striatum.In addition,CXCR7 antibody increased the expression of CXCR4 in the striatum,increased the protein expression of RAS and ERK1/2 associated with the RAS/ERK signaling pathway,and im proved rat motor function.These findings suggest that CXCR7 improved neural functional recovery after ischemic stroke by promoting axonal regeneration,synaptogenesis,and myelin regeneration,which may be achieved by activation of CXCR4 and the RAS/ERK1/2 signaling pathway.展开更多
BACKGROUND Human-derived mesenchymal stromal cells have been shown to improve cognitive function following experimental stroke.The activity of exosomes has been verified to be comparable to the therapeutic effects of ...BACKGROUND Human-derived mesenchymal stromal cells have been shown to improve cognitive function following experimental stroke.The activity of exosomes has been verified to be comparable to the therapeutic effects of mesenchymal stromal cells.However,the effects of exosomes derived from human umbilical cord mesenchymal stem cells(HUC-MSCs)(ExoCtrl)on post-stroke cognitive impairment(PSCI)have rarely been reported.Moreover,whether exosomes derived from C-C chemokine receptor type 2(CCR2)-overexpressing HUC-MSCs(ExoCCR2)can enhance the therapeutic effects on PSCI and the possible underlying mechanisms have not been studied.AIM To investigate the effects of ExoCtrl on PSCI and whether ExoCCR2 can enhance therapeutic effects on PSCI.METHODS Transmission electron microscopy,qNano®particles analyzer,and Western blotting were employed to determine the morphology and CCR2 expression of ExoCtrl or ExoCCR2.ELISA was used to study the binding capacity of exosomes to CC chemokine ligand 2(CCL2)in vivo.After the intravenous injection of ExoCtrl or ExoCCR2 into experimental rats,the effect of ExoCtrl and ExoCCR2 on PSCI was assessed by Morris water maze.Remyelination and oligodendrogenesis were analyzed by Western blotting and immunofluorescence microscopy.QRT-PCR and immunofluorescence microscopy were conducted to compare the microglia/macrophage polarization.The infiltration and activation of hematogenous macrophages were analyzed by Western blotting and transwell migration analysis.RESULTS CCR2-overexpressing HUC-MSCs loaded the CCR2 receptor into their exosomes.The morphology and diameter distribution between ExoCtrl and ExoCCR2 showed no significant difference.ExoCCR2 bound significantly to CCL2 but ExoCtrl showed little CCL2 binding.Although both ExoCCR2 and ExoCtrl showed beneficial effects on PSCI,oligodendrogenesis,remyelination,and microglia/macrophage polarization,ExoCCR2 exhibited a significantly superior beneficial effect.We also found that ExoCCR2 could suppress the CCL2-induced macrophage migration and activation in vivo and in vitro,compared with ExoCtrl treated group.CONCLUSION CCR2 over-expression enhanced the therapeutic effects of exosomes on the experimental PSCI by promoting M2 microglia/macrophage polarization,enhancing oligodendrogenesis and remyelination.These therapeutic effects are likely through suppressing the CCL2-induced hematogenous macrophage migration and activation.Key words:Cognitive impairment;Stroke;Exosomes;C-C chemokine receptor type 2;Microglia/macrophage polarization;Remyelination.展开更多
BACKGROUND Massive hepatocyte death is the core event in acute liver failure(ALF).Gasdermin D(GSDMD)-mediated pyroptosis is a type of highly inflammatory cell death.However,the role of hepatocyte pyroptosis and its me...BACKGROUND Massive hepatocyte death is the core event in acute liver failure(ALF).Gasdermin D(GSDMD)-mediated pyroptosis is a type of highly inflammatory cell death.However,the role of hepatocyte pyroptosis and its mechanisms of expanding inflammatory responses in ALF are unclear.AIM To investigate the role and mechanisms of GSDMD-mediated hepatocyte pyroptosis through in vitro and in vivo experiments.METHODS The expression of pyroptosis pathway-associated proteins in liver tissues from ALF patients and a hepatocyte injury model was examined by Western blot.GSDMD short hairpin RNA(shRNA)was used to investigate the effects of downregulation of GSDMD on monocyte chemotactic protein 1(MCP1)and its receptor CC chemokine receptor-2(CCR2)in vitro.For in vivo experiments,we used GSDMD knockout mice to investigate the role and mechanism of GSDMD in a D-galactose/lipopolysaccharide(D-Galn/LPS)-induced ALF mouse model.RESULTS The levels of pyroptosis pathway-associated proteins in liver tissue from ALF patients and a hepatocyte injury model increased significantly.The level of GSDMD-N protein increased most obviously(P<0.001).In vitro,downregulation of GSDMD by shRNA decreased the cell inhibition rate and the levels of MCP1/CCR2 proteins(P<0.01).In vivo,GSDMD knockout dramatically eliminated inflammatory damage in the liver and improved the survival of DGaln/LPS-induced ALF mice(P<0.001).Unlike the mechanism of immune cell pyroptosis that involves releasing interleukin(IL)-1βand IL-18,GSDMDmediated hepatocyte pyroptosis recruited macrophages via MCP1/CCR2 to aggravate hepatocyte death.However,this pathological process was inhibited after knocking down GSDMD.CONCLUSION GSDMD-mediated hepatocyte pyroptosis plays an important role in the pathogenesis of ALF,recruiting macrophages to release inflammatory mediators by upregulating MCP1/CCR2 and leading to expansion of the inflammatory responses.GSDMD knockout can reduce hepatocyte death and inflammatory responses,thus alleviating ALF.展开更多
Previous studies have shown that microglia impact the proliferation and differentiation of neu- rons during hippocampal neurogenesis via the fractalkine/CX3 chemokine receptor i （CX3CRI） signaling pathway. However, ...Previous studies have shown that microglia impact the proliferation and differentiation of neu- rons during hippocampal neurogenesis via the fractalkine/CX3 chemokine receptor i （CX3CRI） signaling pathway. However, whether microglia can influence the maturation and dendritic growth of newborn neurons during hippocampal neurogenesis remains unclear. In the present study, we found that the number of doublecortin-positive cells in the hippocampus was decreased, and the dendritic length and number of intersections in newborn neurons in the hippocampus were reduced in transgenic adult mice with CX3CR1 deficiency （CX3CRl^GFP/GFe）. Furthermore, after experimental seizures were induced with kainic acid in these CX3CRl-deficient mice, the expression of c-fos, a marker of neuronal activity, was reduced compared with wild-type mice. Collectively, the experimental findings indicate that the functional maturation of newborn neu- rons during hippocampal neurogenesis in adult mice is delayed by CX3CR1 deficiency.展开更多
Background: Recent studies indicate that C-X-C motif chemokine receptor 4(CXCR4) and its ligand, C-X-C motif chemokine ligand 12(CXCL12), stimulate expression of the cell cycle regulatory protein Cyclin D1 in neurofib...Background: Recent studies indicate that C-X-C motif chemokine receptor 4(CXCR4) and its ligand, C-X-C motif chemokine ligand 12(CXCL12), stimulate expression of the cell cycle regulatory protein Cyclin D1 in neurofibromatosis 1-associated malignant peripheral nerve sheath tumor(MPNST) cells and promote their proliferation. In this study, we measured the expression of CXCR4, CXCL12, and Cyclin D1 proteins in sporadic MPNST tissues from Chinese patients and investigated their prognostic values.Methods: CXCR4, CXCL12, and Cyclin D1 protein expression in samples from 58 Chinese patients with sporadic MPNST was assessed with immunohistochemical staining.Their prognostic values were evaluated with Kaplan-Meier analysis and a log-rank test. Multivariate Cox regression analysis was used to identify independent prognostic factors.Results: High expression of CXCR4, CXCL12, and Cyclin D1 was observed in 19(32.8%), 32(55.2%), and 16(27.6%)samples, respectively. CXCR4 expression was positively correlated with CXCL12 expression(r = 0.334, P = 0.010) and Cyclin D1 expression(r = 0.309, P = 0.018). Patients with high CXCR4 expression showed longer overall survival than those with low CXCR4 expression(χ~2 = 4.642, P = 0.031).Conclusion: High CXCR4 expression may define a specific subtype of sporadic MPNST with favorable prognosis.展开更多
基金supported by the National Natural Science Foundation of China(Key Program),No.11932013the National Natural Science Foundation of China(General Program),No.82272255+2 种基金Armed Police Force High-Level Science and Technology Personnel ProjectThe Armed Police Force Focuses on Supporting Scientific and Technological Innovation TeamsKey Project of Tianjin Science and Technology Plan,No.20JCZDJC00570(all to XC)。
文摘Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory damage.The expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after injury.Recent studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for treatment.This review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord injury.Additionally,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted drugs.Nevertheless,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.
基金supported by the National Natural Science Foundation of China,Nos.81401002 (to SSZ),81801 053 (to XQZ)。
文摘Stromal cell-derived factor-1 and its receptor C-X-C chemokine receptor 4(CXCR4) have been shown to regulate neural regeneration after stroke.Howeve r,whether stromal cell-derived factor-1 receptor CXCR7,which is widely distributed in the develo ping and adult central nervous system,participates in neural regeneration remains poorly unde rstood.In this study,we established rat models of focal cerebral ischemia by injecting endothelin-1 into the cerebral co rtex and striatum.Starting on day 7 after injury,CXCR7-neutralizing antibody was injected into the lateral ventricle using a micro drug delivery system for 6 consecutive days.Our results showed that CXCR7-neutralizing antibody increased the total length and number of sprouting co rticospinal tra ct fibers in rats with cerebral ischemia,increased the expression of vesicular glutamate transporter 1 and growth-related protein 43,marke rs of the denervated spinal cord synapses,and promoted the differentiation and maturation of oligodendrocyte progenitor cells in the striatum.In addition,CXCR7 antibody increased the expression of CXCR4 in the striatum,increased the protein expression of RAS and ERK1/2 associated with the RAS/ERK signaling pathway,and im proved rat motor function.These findings suggest that CXCR7 improved neural functional recovery after ischemic stroke by promoting axonal regeneration,synaptogenesis,and myelin regeneration,which may be achieved by activation of CXCR4 and the RAS/ERK1/2 signaling pathway.
基金the National Natural Science Foundation of China,No.81871847 and No.81672261
文摘BACKGROUND Human-derived mesenchymal stromal cells have been shown to improve cognitive function following experimental stroke.The activity of exosomes has been verified to be comparable to the therapeutic effects of mesenchymal stromal cells.However,the effects of exosomes derived from human umbilical cord mesenchymal stem cells(HUC-MSCs)(ExoCtrl)on post-stroke cognitive impairment(PSCI)have rarely been reported.Moreover,whether exosomes derived from C-C chemokine receptor type 2(CCR2)-overexpressing HUC-MSCs(ExoCCR2)can enhance the therapeutic effects on PSCI and the possible underlying mechanisms have not been studied.AIM To investigate the effects of ExoCtrl on PSCI and whether ExoCCR2 can enhance therapeutic effects on PSCI.METHODS Transmission electron microscopy,qNano®particles analyzer,and Western blotting were employed to determine the morphology and CCR2 expression of ExoCtrl or ExoCCR2.ELISA was used to study the binding capacity of exosomes to CC chemokine ligand 2(CCL2)in vivo.After the intravenous injection of ExoCtrl or ExoCCR2 into experimental rats,the effect of ExoCtrl and ExoCCR2 on PSCI was assessed by Morris water maze.Remyelination and oligodendrogenesis were analyzed by Western blotting and immunofluorescence microscopy.QRT-PCR and immunofluorescence microscopy were conducted to compare the microglia/macrophage polarization.The infiltration and activation of hematogenous macrophages were analyzed by Western blotting and transwell migration analysis.RESULTS CCR2-overexpressing HUC-MSCs loaded the CCR2 receptor into their exosomes.The morphology and diameter distribution between ExoCtrl and ExoCCR2 showed no significant difference.ExoCCR2 bound significantly to CCL2 but ExoCtrl showed little CCL2 binding.Although both ExoCCR2 and ExoCtrl showed beneficial effects on PSCI,oligodendrogenesis,remyelination,and microglia/macrophage polarization,ExoCCR2 exhibited a significantly superior beneficial effect.We also found that ExoCCR2 could suppress the CCL2-induced macrophage migration and activation in vivo and in vitro,compared with ExoCtrl treated group.CONCLUSION CCR2 over-expression enhanced the therapeutic effects of exosomes on the experimental PSCI by promoting M2 microglia/macrophage polarization,enhancing oligodendrogenesis and remyelination.These therapeutic effects are likely through suppressing the CCL2-induced hematogenous macrophage migration and activation.Key words:Cognitive impairment;Stroke;Exosomes;C-C chemokine receptor type 2;Microglia/macrophage polarization;Remyelination.
基金Supported by the National Natural Science Foundation of China,No.81570543 and No.81560104
文摘BACKGROUND Massive hepatocyte death is the core event in acute liver failure(ALF).Gasdermin D(GSDMD)-mediated pyroptosis is a type of highly inflammatory cell death.However,the role of hepatocyte pyroptosis and its mechanisms of expanding inflammatory responses in ALF are unclear.AIM To investigate the role and mechanisms of GSDMD-mediated hepatocyte pyroptosis through in vitro and in vivo experiments.METHODS The expression of pyroptosis pathway-associated proteins in liver tissues from ALF patients and a hepatocyte injury model was examined by Western blot.GSDMD short hairpin RNA(shRNA)was used to investigate the effects of downregulation of GSDMD on monocyte chemotactic protein 1(MCP1)and its receptor CC chemokine receptor-2(CCR2)in vitro.For in vivo experiments,we used GSDMD knockout mice to investigate the role and mechanism of GSDMD in a D-galactose/lipopolysaccharide(D-Galn/LPS)-induced ALF mouse model.RESULTS The levels of pyroptosis pathway-associated proteins in liver tissue from ALF patients and a hepatocyte injury model increased significantly.The level of GSDMD-N protein increased most obviously(P<0.001).In vitro,downregulation of GSDMD by shRNA decreased the cell inhibition rate and the levels of MCP1/CCR2 proteins(P<0.01).In vivo,GSDMD knockout dramatically eliminated inflammatory damage in the liver and improved the survival of DGaln/LPS-induced ALF mice(P<0.001).Unlike the mechanism of immune cell pyroptosis that involves releasing interleukin(IL)-1βand IL-18,GSDMDmediated hepatocyte pyroptosis recruited macrophages via MCP1/CCR2 to aggravate hepatocyte death.However,this pathological process was inhibited after knocking down GSDMD.CONCLUSION GSDMD-mediated hepatocyte pyroptosis plays an important role in the pathogenesis of ALF,recruiting macrophages to release inflammatory mediators by upregulating MCP1/CCR2 and leading to expansion of the inflammatory responses.GSDMD knockout can reduce hepatocyte death and inflammatory responses,thus alleviating ALF.
文摘Previous studies have shown that microglia impact the proliferation and differentiation of neu- rons during hippocampal neurogenesis via the fractalkine/CX3 chemokine receptor i （CX3CRI） signaling pathway. However, whether microglia can influence the maturation and dendritic growth of newborn neurons during hippocampal neurogenesis remains unclear. In the present study, we found that the number of doublecortin-positive cells in the hippocampus was decreased, and the dendritic length and number of intersections in newborn neurons in the hippocampus were reduced in transgenic adult mice with CX3CR1 deficiency （CX3CRl^GFP/GFe）. Furthermore, after experimental seizures were induced with kainic acid in these CX3CRl-deficient mice, the expression of c-fos, a marker of neuronal activity, was reduced compared with wild-type mice. Collectively, the experimental findings indicate that the functional maturation of newborn neu- rons during hippocampal neurogenesis in adult mice is delayed by CX3CR1 deficiency.
基金supported by the National Nature Science Foundation of China(81372872 to Jilong Yang,81672650 to Ze Zhu,and 81402215 to Xiaoling Du)funds from the University Cancer Foundation via the Sister Institution Network Fund(to Jilong Yang)
文摘Background: Recent studies indicate that C-X-C motif chemokine receptor 4(CXCR4) and its ligand, C-X-C motif chemokine ligand 12(CXCL12), stimulate expression of the cell cycle regulatory protein Cyclin D1 in neurofibromatosis 1-associated malignant peripheral nerve sheath tumor(MPNST) cells and promote their proliferation. In this study, we measured the expression of CXCR4, CXCL12, and Cyclin D1 proteins in sporadic MPNST tissues from Chinese patients and investigated their prognostic values.Methods: CXCR4, CXCL12, and Cyclin D1 protein expression in samples from 58 Chinese patients with sporadic MPNST was assessed with immunohistochemical staining.Their prognostic values were evaluated with Kaplan-Meier analysis and a log-rank test. Multivariate Cox regression analysis was used to identify independent prognostic factors.Results: High expression of CXCR4, CXCL12, and Cyclin D1 was observed in 19(32.8%), 32(55.2%), and 16(27.6%)samples, respectively. CXCR4 expression was positively correlated with CXCL12 expression(r = 0.334, P = 0.010) and Cyclin D1 expression(r = 0.309, P = 0.018). Patients with high CXCR4 expression showed longer overall survival than those with low CXCR4 expression(χ~2 = 4.642, P = 0.031).Conclusion: High CXCR4 expression may define a specific subtype of sporadic MPNST with favorable prognosis.
