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
Severe acute respiratory syndrome coronavirus 2(SARSCoV-2)infection has been extensively shown to cause many neurological sequelae,and cognitive deficits(known as“brain fog”)may particularly and widely occur even in...Severe acute respiratory syndrome coronavirus 2(SARSCoV-2)infection has been extensively shown to cause many neurological sequelae,and cognitive deficits(known as“brain fog”)may particularly and widely occur even in individuals with mild symptoms[1].Peripheral hyperinflammation as well as central nervous system(CNS)local immune responses may synergistically contribute to brain autoimmune injury.In addition to the direct neuroinvasion of SARS-CoV-2 and nonimmune effects such as severe systemic hypoxemia and vascular thrombosis,the central mechanism by which SARSCoV-2 accelerates cognitive-related symptoms may be related to immune effects[2].However,the precise neuroinflammatory mechanisms of SARS-CoV-2 infection have not been fully established.Fernández-Casta-da et al.[3]provided direct evidence and unique insights into the potential mechanism of cognitive impairment in mild respiratory coronavirus disease 2019(COVID-19)cases.展开更多
Mounting evidence supports an important role of chemokines, produced by spinal cord astrocytes, in promoting central sensitization and chronic pain. In particular, CCL2 （C-C motif chemokine ligand 2） has been shown ...Mounting evidence supports an important role of chemokines, produced by spinal cord astrocytes, in promoting central sensitization and chronic pain. In particular, CCL2 （C-C motif chemokine ligand 2） has been shown to enhance N-methyl-D-aspartate （NMDA）-induced currents in spinal outer lamina II （Iio） neurons. However, the exact molecular, synaptic, and cellular mechanisms by which CCL2 modulates central sensitization are still unclear. We found that spinal injection of the CCR2 antagonist RS504393 attenuated CCL2- and inflammation-induced hyperalgesia. Single-cell RT-PCR revealed CCR2 expres- sion in excitatory vesicular glutamate transporter subtype 2-positive （VGLUT2＋） neurons. CCL2 increased NMDA- induced currents in CCR2＋/VGLUT2＋ neurons in lamina IIo; it also enhanced the synaptic NMDA currents evoked by dorsal root stimulation; and furthermore, it increased the total and synaptic NMDA currents in somatostatin- expressing excitatory neurons. Finally, intrathecal RS504393 reversed the long-term potentiation evoked in the spinal cord by C-fiber stimulation. Our findings suggest that CCL2 directly modulates synaptic plasticity in CCR2- expressing excitatory neurons in spinal lamina Iio, and this underlies the generation of central sensitization in patho- logical pain.展开更多
Inflammation,which is mediated by leukocyte trafficking and activation,plays a prominent role in the pathogenesis of acute and chronic liver injury.Chemokines are critical mediators involved in the migration of leukoc...Inflammation,which is mediated by leukocyte trafficking and activation,plays a prominent role in the pathogenesis of acute and chronic liver injury.Chemokines are critical mediators involved in the migration of leukocytes into the diseased liver via binding to their G protein-coupled receptors.CeC motif ligand 5(CCL5)belongs to the CC-chemokine family and is secreted by several hepatic cell pop-ulations including hepatocytes,macrophages,hepatic stellate cells,and endothelial cells upon activation.CCL5 regulates the recruitment and migration of T cells(via CCR5)and NK cells(via CCR1).Moreover,CCL5 activates and stimulates T cell proliferation and cytokine production,sequentially regulating in-flammatory responses.Accumulating studies have identified crucial effects of CCL5 both in liver-disease patients and in experimental models,in which CCL5 is elevated and displays distinct effects according to pathological conditions.In this review,we discussed the crucial functions of CCL5 in liver diseases,including acute liver failure,hepatic ischemia-reperfusion injury,acute liver failure,acute and viral hepatitis,alcoholic liver disease,non-alcoholic fatty liver disease,fibrosis,and hepatocellular carcinoma.Continued understanding the roles of CCL5 in liver disease and their mechanisms of activation are indispensable for the development of effective clinical therapeutics.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 grants from the National Natural Science Foundation of China(82001240)Natural Science Foundation of Heilongjiang Province(YQ2021H011)+1 种基金China Postdoctoral Science Foundation(2020M670925,2022T150172)Postdoctoral Foundation of Heilongjiang Province(LBHZ19027,LBH-TZ2019).
文摘Severe acute respiratory syndrome coronavirus 2(SARSCoV-2)infection has been extensively shown to cause many neurological sequelae,and cognitive deficits(known as“brain fog”)may particularly and widely occur even in individuals with mild symptoms[1].Peripheral hyperinflammation as well as central nervous system(CNS)local immune responses may synergistically contribute to brain autoimmune injury.In addition to the direct neuroinvasion of SARS-CoV-2 and nonimmune effects such as severe systemic hypoxemia and vascular thrombosis,the central mechanism by which SARSCoV-2 accelerates cognitive-related symptoms may be related to immune effects[2].However,the precise neuroinflammatory mechanisms of SARS-CoV-2 infection have not been fully established.Fernández-Casta-da et al.[3]provided direct evidence and unique insights into the potential mechanism of cognitive impairment in mild respiratory coronavirus disease 2019(COVID-19)cases.
基金supported by grants from the National Natural Science Foundation of China(31400949,81502102,31471059,81371498,and 31371121)NIH R01,USA Grants(DE17794,DE22743,and NS87988)
文摘Mounting evidence supports an important role of chemokines, produced by spinal cord astrocytes, in promoting central sensitization and chronic pain. In particular, CCL2 （C-C motif chemokine ligand 2） has been shown to enhance N-methyl-D-aspartate （NMDA）-induced currents in spinal outer lamina II （Iio） neurons. However, the exact molecular, synaptic, and cellular mechanisms by which CCL2 modulates central sensitization are still unclear. We found that spinal injection of the CCR2 antagonist RS504393 attenuated CCL2- and inflammation-induced hyperalgesia. Single-cell RT-PCR revealed CCR2 expres- sion in excitatory vesicular glutamate transporter subtype 2-positive （VGLUT2＋） neurons. CCL2 increased NMDA- induced currents in CCR2＋/VGLUT2＋ neurons in lamina IIo; it also enhanced the synaptic NMDA currents evoked by dorsal root stimulation; and furthermore, it increased the total and synaptic NMDA currents in somatostatin- expressing excitatory neurons. Finally, intrathecal RS504393 reversed the long-term potentiation evoked in the spinal cord by C-fiber stimulation. Our findings suggest that CCL2 directly modulates synaptic plasticity in CCR2- expressing excitatory neurons in spinal lamina Iio, and this underlies the generation of central sensitization in patho- logical pain.
基金This work was supported by the National Natural Science Foundation of China(81873582 and 81670562 to X.Kong).
文摘Inflammation,which is mediated by leukocyte trafficking and activation,plays a prominent role in the pathogenesis of acute and chronic liver injury.Chemokines are critical mediators involved in the migration of leukocytes into the diseased liver via binding to their G protein-coupled receptors.CeC motif ligand 5(CCL5)belongs to the CC-chemokine family and is secreted by several hepatic cell pop-ulations including hepatocytes,macrophages,hepatic stellate cells,and endothelial cells upon activation.CCL5 regulates the recruitment and migration of T cells(via CCR5)and NK cells(via CCR1).Moreover,CCL5 activates and stimulates T cell proliferation and cytokine production,sequentially regulating in-flammatory responses.Accumulating studies have identified crucial effects of CCL5 both in liver-disease patients and in experimental models,in which CCL5 is elevated and displays distinct effects according to pathological conditions.In this review,we discussed the crucial functions of CCL5 in liver diseases,including acute liver failure,hepatic ischemia-reperfusion injury,acute liver failure,acute and viral hepatitis,alcoholic liver disease,non-alcoholic fatty liver disease,fibrosis,and hepatocellular carcinoma.Continued understanding the roles of CCL5 in liver disease and their mechanisms of activation are indispensable for the development of effective clinical therapeutics.
