Axons in central nervous system （CNS） do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord iniury. Both intrinsic and extrinsic factors are responsible for the regeneration fail- u...Axons in central nervous system （CNS） do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord iniury. Both intrinsic and extrinsic factors are responsible for the regeneration fail- ure, Although intensive research efforts have been invested on extrinsic regeneration inhibitors, the extent to which glial inhibitors contribute to the regeneration failure in viva still remains elusive. Recent exper- imental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals. In this review, we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons. Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neu- rons is enhanced by a preceding injury to the peripheral branches, we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of en- hanced regeneration capacity. Neuron-derived chemokine （C-C motif） ligand 2 （CCL2） seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype, which we designate as regeneration-associated macrophages （RAMs）. Ma- nipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury, suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries.展开更多
Both cholinergic dysfunction and protein citrullination are the hallmarks of rheumatoid arthritis(RA),but the relationship between the two phenomena remains unclear.We explored whether and how cholinergic dysfunction ...Both cholinergic dysfunction and protein citrullination are the hallmarks of rheumatoid arthritis(RA),but the relationship between the two phenomena remains unclear.We explored whether and how cholinergic dysfunction accelerates protein citrullination and consequently drives the development of RA.Cholinergic function and protein citrullination levels in patients with RA and collageninduced arthritis(CIA)mice were collected.In both neuron-macrophage coculture system and CIA mice,the effect of cholinergic dysfunction on protein citrullination and expression of peptidylarginine deiminases(PADs)was assessed by immunofluorescence.The key transcription factors for PAD4 expression were predicted and validated.Cholinergic dysfunction in the patients with RA and CIA mice negatively correlated with the degree of protein citrullination in synovial tissues.The cholinergic or alpha7 nicotinic acetylcholine receptor(a7nAChR)deactivation and activation resulted in the promotion and reduction of protein citrullination in vitro and in vivo,respectively.Especially,the activation deficiency of a7nAChR induced the earlier onset and aggravation of CIA.Furthermore,deactivation of a7nAChR increased the expression of PAD4 and specificity protein-3(SP3)in vitro and in vivo.Our results suggest that cholinergic dysfunction-induced deficient a7nAChR activation,which induces the expression of SP3 and its downstream molecule PAD4,accelerating protein citrullination and the development of RA.展开更多
文摘Axons in central nervous system （CNS） do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord iniury. Both intrinsic and extrinsic factors are responsible for the regeneration fail- ure, Although intensive research efforts have been invested on extrinsic regeneration inhibitors, the extent to which glial inhibitors contribute to the regeneration failure in viva still remains elusive. Recent exper- imental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals. In this review, we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons. Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neu- rons is enhanced by a preceding injury to the peripheral branches, we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of en- hanced regeneration capacity. Neuron-derived chemokine （C-C motif） ligand 2 （CCL2） seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype, which we designate as regeneration-associated macrophages （RAMs）. Ma- nipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury, suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries.
基金supported by the“Double First-Class”University Project(CPU2022QZ31,China)。
文摘Both cholinergic dysfunction and protein citrullination are the hallmarks of rheumatoid arthritis(RA),but the relationship between the two phenomena remains unclear.We explored whether and how cholinergic dysfunction accelerates protein citrullination and consequently drives the development of RA.Cholinergic function and protein citrullination levels in patients with RA and collageninduced arthritis(CIA)mice were collected.In both neuron-macrophage coculture system and CIA mice,the effect of cholinergic dysfunction on protein citrullination and expression of peptidylarginine deiminases(PADs)was assessed by immunofluorescence.The key transcription factors for PAD4 expression were predicted and validated.Cholinergic dysfunction in the patients with RA and CIA mice negatively correlated with the degree of protein citrullination in synovial tissues.The cholinergic or alpha7 nicotinic acetylcholine receptor(a7nAChR)deactivation and activation resulted in the promotion and reduction of protein citrullination in vitro and in vivo,respectively.Especially,the activation deficiency of a7nAChR induced the earlier onset and aggravation of CIA.Furthermore,deactivation of a7nAChR increased the expression of PAD4 and specificity protein-3(SP3)in vitro and in vivo.Our results suggest that cholinergic dysfunction-induced deficient a7nAChR activation,which induces the expression of SP3 and its downstream molecule PAD4,accelerating protein citrullination and the development of RA.
