Spinal cord injury causes accumulation of a large number of leukocytes at the lesion site where they contribute to excessive inflammation.Overproduced chemokines are responsible for the migratory process of the leukoc...Spinal cord injury causes accumulation of a large number of leukocytes at the lesion site where they contribute to excessive inflammation.Overproduced chemokines are responsible for the migratory process of the leukocytes,but the regulatory mechanism underlying the production of chemokines from resident cells of the spinal cord has not been fully elucidated.We examined the protein levels of macrophage migration inhibitory factor and chemokine C-C motif chemokine ligand 2 in a spinal cord contusion model at different time points following spinal cord injury.The elevation of macrophage migration inhibitory factor at the lesion site coincided with the increase of chemokine C-C motif chemokine ligand 2 abundance in astrocytes.Stimulation of primary cultured astrocytes with different concentrations of macrophage migration inhibitory factor recombinant protein induced chemokine C-C motif chemokine ligand 2 production from the cells,and the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine attenuated the stimulatory effect.Further investigation into the underlying mechanism on macrophage migration inhibitory factor-mediated astrocytic production of chemokine C-C motif chemokine ligand 2 revealed that macrophage migration inhibitory factor activated intracellular JNK signaling through binding with CD74 receptor.Administration of the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine following spinal cord injury resulted in the reduction of chemokine C-C motif chemokine ligand 2-recruited microglia/macrophages at the lesion site and remarkably improved the hindlimb locomotor function of rats.Our results have provided insights into the functions of astrocyte-activated chemokines in the recruitment of leukocytes and may be beneficial to develop interventions targeting chemokine C-C motif chemokine ligand 2 for neuroinflammation after spinal cord injury.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
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
Atypical chemokine receptors have recently emerged as important molecular players in health and diseases; they affect chemokine availability and function and impact a multitude of pathophysiological events, including ...Atypical chemokine receptors have recently emerged as important molecular players in health and diseases; they affect chemokine availability and function and impact a multitude of pathophysiological events, including the tumorigenesis process. This family of atypical receptors comprises five members: ACKR1/DARC, ACKR2/D6,ACKR3/CXCR7, ACKR4/CCRL1, and ACKR5/CCRL2. This work evaluated the differential expression of these receptors in prostate cancer using quantitative PCR. Further evaluation of CCRL2 at the protein level confirmed its overexpression in a metastatic cell line and in malignant prostatic tissues from patients. CCRL2, a presumed member of the atypical chemokine receptor family, plays a key role in lung dendritic cell trafficking to peripheral lymph nodes.Recent studies have reported the expression of CCRL2 in different human cancer cell lines and tissues. However, its function and expression in prostate cancer has not been previously addressed.展开更多
The surface antigen CD14 plays an important role in innate immunity, serving as a pattern recognition receptor for lipopolysaccharides (LPS). The aim of this study was to investigate the proliferation, NFκB activatio...The surface antigen CD14 plays an important role in innate immunity, serving as a pattern recognition receptor for lipopolysaccharides (LPS). The aim of this study was to investigate the proliferation, NFκB activation, and chemokine secretion of BEAS-2B cells, a human bronchial epithelial cell line, after LPS stimulation, and some details of inVolved signaling. The presence of CD14 was investigated by flow cytometry. Cell proliferation was measured with a [3H]-thymidine incorporation assay. sCD14, RANTES, and IL-8 concentrations in cell supernatants were measured by ELISA. BEAS-2B cells express CD14 on their surface and secrete soluble CD14 into the supernatant. Cells react on LPS with increased proliferation, activation of NFκB, and the secretion of the pro-inflammatory chemotactic cytokines IL-8 and RANTES, which proves the functionality of the CD14 receptor. Neither CD14 nor sCD14 are regulated by LPS. Specific inhibitors of various intracellular signaling pathways diminish the LPS-induced proliferation and IL-8 secretion: Thus MAP-Kinases p38 and JNK, tyrosine kinases, and PI3-kinase are involved in the signaling cascade from the LPS-CD14-complex on the cell surface to the increased cell proliferation and expression of IL-8;furthermore, ERK 1/2, IRAK 1/4, and the NFκB pathway are inVolved in the latter. The data show the existence and functionality of CD14 receptors on BEAS-2B cells and elucidate the signaling pathways inVolved. LPS is able to increase cell prolife-ration, various cytokines which are dependent on endogenous CD14. Three MAPK pathways, PI3 kinase and tyrosine kinase may be involved. Also CD14 is present/involved which was controversial.展开更多
目的探究利拉鲁肽与西格列汀对早期2型糖尿病肾病(T2DN)患者肾脏血流动力学及中性粒细胞/淋巴细胞比值(NLR)、血清胱抑素C(CysC)、单核细胞趋化因子-1(MCP-1)的影响。方法选取2020年12月—2022年12月邯郸市第一医院内分泌一科收治的早期...目的探究利拉鲁肽与西格列汀对早期2型糖尿病肾病(T2DN)患者肾脏血流动力学及中性粒细胞/淋巴细胞比值(NLR)、血清胱抑素C(CysC)、单核细胞趋化因子-1(MCP-1)的影响。方法选取2020年12月—2022年12月邯郸市第一医院内分泌一科收治的早期T2DN患者110例为研究对象。按随机数排秩法将患者分为对照组(n=55)与观察组(n=55)。对照组予以西格列汀治疗,观察组予以利拉鲁肽联合西格列汀治疗,2组患者均治疗12周。比较2组疗效、血糖指标、双肾主动脉(MRA)和叶间动脉(IRA)的肾脏血流动力学指标、NLR、Cys-C、MCP-1以及不良反应发生情况,分析尿蛋白排泄率(UAER)与血清NLR、CysC、MCP-1的关系。结果观察组总有效率为90.91%,高于对照组的67.27%(χ^(2)/P=9.290/0.002)。治疗12周后,2组HbA_(1c)、FPG、2 h PG水平较治疗前降低,且观察组低于对照组(t/P=4.222/<0.001、6.064/<0.001、6.648/<0.001);2组IRA、MRA的Vdmin、Vsmax较治疗前升高,且观察组较对照组升高更明显(t/P=3.733/<0.001、6.800/<0.001,2.598/0.011、2.043/0.043);2组IRA、MRA的PI、RI较治疗前降低,且观察组较对照组降低更明显(t/P=4.194/<0.001、3.933/<0.001,3.265/0.001、6.171/<0.001);2组UAER、NLR、Cys-C、MCP-1水平较治疗前明显降低,且观察组较对照组降低更明显(t/P=14.534/<0.001、2.609/0.010、9.795/<0.001、6.618/<0.001);Pearson分析,NLR、Cys-C、MCP-1与UAER均呈正相关(r=0.513、0.764、0.685,P均<0.001)。2组不良反应发生率比较差异无统计学意义(χ^(2)/P=0.910/0.340)。结论利拉鲁肽联合西格列汀治疗早期T2DN具有良好疗效,可有效改善肾脏血流动力学,调节NLR、Cys-C、MCP-1水平,保护肾功能。展开更多
基金supported by the China Postdoctoral Science Foundation,No.2020M681689(to YMH)the Basic Scientific Research Projects of Nantong,Nos.JC2020015(to HX)and JC2020041(to YMH)。
文摘Spinal cord injury causes accumulation of a large number of leukocytes at the lesion site where they contribute to excessive inflammation.Overproduced chemokines are responsible for the migratory process of the leukocytes,but the regulatory mechanism underlying the production of chemokines from resident cells of the spinal cord has not been fully elucidated.We examined the protein levels of macrophage migration inhibitory factor and chemokine C-C motif chemokine ligand 2 in a spinal cord contusion model at different time points following spinal cord injury.The elevation of macrophage migration inhibitory factor at the lesion site coincided with the increase of chemokine C-C motif chemokine ligand 2 abundance in astrocytes.Stimulation of primary cultured astrocytes with different concentrations of macrophage migration inhibitory factor recombinant protein induced chemokine C-C motif chemokine ligand 2 production from the cells,and the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine attenuated the stimulatory effect.Further investigation into the underlying mechanism on macrophage migration inhibitory factor-mediated astrocytic production of chemokine C-C motif chemokine ligand 2 revealed that macrophage migration inhibitory factor activated intracellular JNK signaling through binding with CD74 receptor.Administration of the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine following spinal cord injury resulted in the reduction of chemokine C-C motif chemokine ligand 2-recruited microglia/macrophages at the lesion site and remarkably improved the hindlimb locomotor function of rats.Our results have provided insights into the functions of astrocyte-activated chemokines in the recruitment of leukocytes and may be beneficial to develop interventions targeting chemokine C-C motif chemokine ligand 2 for neuroinflammation after spinal cord injury.
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.
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.
文摘Atypical chemokine receptors have recently emerged as important molecular players in health and diseases; they affect chemokine availability and function and impact a multitude of pathophysiological events, including the tumorigenesis process. This family of atypical receptors comprises five members: ACKR1/DARC, ACKR2/D6,ACKR3/CXCR7, ACKR4/CCRL1, and ACKR5/CCRL2. This work evaluated the differential expression of these receptors in prostate cancer using quantitative PCR. Further evaluation of CCRL2 at the protein level confirmed its overexpression in a metastatic cell line and in malignant prostatic tissues from patients. CCRL2, a presumed member of the atypical chemokine receptor family, plays a key role in lung dendritic cell trafficking to peripheral lymph nodes.Recent studies have reported the expression of CCRL2 in different human cancer cell lines and tissues. However, its function and expression in prostate cancer has not been previously addressed.
文摘The surface antigen CD14 plays an important role in innate immunity, serving as a pattern recognition receptor for lipopolysaccharides (LPS). The aim of this study was to investigate the proliferation, NFκB activation, and chemokine secretion of BEAS-2B cells, a human bronchial epithelial cell line, after LPS stimulation, and some details of inVolved signaling. The presence of CD14 was investigated by flow cytometry. Cell proliferation was measured with a [3H]-thymidine incorporation assay. sCD14, RANTES, and IL-8 concentrations in cell supernatants were measured by ELISA. BEAS-2B cells express CD14 on their surface and secrete soluble CD14 into the supernatant. Cells react on LPS with increased proliferation, activation of NFκB, and the secretion of the pro-inflammatory chemotactic cytokines IL-8 and RANTES, which proves the functionality of the CD14 receptor. Neither CD14 nor sCD14 are regulated by LPS. Specific inhibitors of various intracellular signaling pathways diminish the LPS-induced proliferation and IL-8 secretion: Thus MAP-Kinases p38 and JNK, tyrosine kinases, and PI3-kinase are involved in the signaling cascade from the LPS-CD14-complex on the cell surface to the increased cell proliferation and expression of IL-8;furthermore, ERK 1/2, IRAK 1/4, and the NFκB pathway are inVolved in the latter. The data show the existence and functionality of CD14 receptors on BEAS-2B cells and elucidate the signaling pathways inVolved. LPS is able to increase cell prolife-ration, various cytokines which are dependent on endogenous CD14. Three MAPK pathways, PI3 kinase and tyrosine kinase may be involved. Also CD14 is present/involved which was controversial.
文摘目的探究利拉鲁肽与西格列汀对早期2型糖尿病肾病(T2DN)患者肾脏血流动力学及中性粒细胞/淋巴细胞比值(NLR)、血清胱抑素C(CysC)、单核细胞趋化因子-1(MCP-1)的影响。方法选取2020年12月—2022年12月邯郸市第一医院内分泌一科收治的早期T2DN患者110例为研究对象。按随机数排秩法将患者分为对照组(n=55)与观察组(n=55)。对照组予以西格列汀治疗,观察组予以利拉鲁肽联合西格列汀治疗,2组患者均治疗12周。比较2组疗效、血糖指标、双肾主动脉(MRA)和叶间动脉(IRA)的肾脏血流动力学指标、NLR、Cys-C、MCP-1以及不良反应发生情况,分析尿蛋白排泄率(UAER)与血清NLR、CysC、MCP-1的关系。结果观察组总有效率为90.91%,高于对照组的67.27%(χ^(2)/P=9.290/0.002)。治疗12周后,2组HbA_(1c)、FPG、2 h PG水平较治疗前降低,且观察组低于对照组(t/P=4.222/<0.001、6.064/<0.001、6.648/<0.001);2组IRA、MRA的Vdmin、Vsmax较治疗前升高,且观察组较对照组升高更明显(t/P=3.733/<0.001、6.800/<0.001,2.598/0.011、2.043/0.043);2组IRA、MRA的PI、RI较治疗前降低,且观察组较对照组降低更明显(t/P=4.194/<0.001、3.933/<0.001,3.265/0.001、6.171/<0.001);2组UAER、NLR、Cys-C、MCP-1水平较治疗前明显降低,且观察组较对照组降低更明显(t/P=14.534/<0.001、2.609/0.010、9.795/<0.001、6.618/<0.001);Pearson分析,NLR、Cys-C、MCP-1与UAER均呈正相关(r=0.513、0.764、0.685,P均<0.001)。2组不良反应发生率比较差异无统计学意义(χ^(2)/P=0.910/0.340)。结论利拉鲁肽联合西格列汀治疗早期T2DN具有良好疗效,可有效改善肾脏血流动力学,调节NLR、Cys-C、MCP-1水平,保护肾功能。
