Adipose mesenchymal stem cells(ADSCs)have protective effects against glutamate-induced excitotoxicity,but ADSCs are limited in use for treatment of optic nerve injury.Studies have shown that the extracellular vesicles...Adipose mesenchymal stem cells(ADSCs)have protective effects against glutamate-induced excitotoxicity,but ADSCs are limited in use for treatment of optic nerve injury.Studies have shown that the extracellular vesicles(EVs)secreted by ADSCs(ADSC-EVs)not only have the function of ADSCs,but also have unique advantages including non-immunogenicity,low probability of abnormal growth,and easy access to target cells.In the present study,we showed that intravitreal injection of ADSC-EVs substantially reduced glutamate-induced damage to retinal morphology and electroretinography.In addition,R28 cell pretreatment with ADSC-EVs before injury inhibited glutamate-induced overload of intracellular calcium,downregulation ofα-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid receptor(AMPAR)subunit GluA2,and phosphorylation of GluA2 and protein kinase C alpha in vitro.A protein kinase C alpha agonist,12-O-tetradecanoylphorbol 13-acetate,inhibited the neuroprotective effects of ADSC-EVs on glutamate-induced R28 cells.These findings suggest that ADSCEVs ameliorate glutamate-induced excitotoxicity in the retina through inhibiting protein kinase C alpha activation.展开更多
Activity-dependent postsynaptic receptor trafficking is critical for long-term synaptic plasticity in the brain, but it is unclear whether this mechanism actually mediates the spinal cord dorsal hom central sensitizat...Activity-dependent postsynaptic receptor trafficking is critical for long-term synaptic plasticity in the brain, but it is unclear whether this mechanism actually mediates the spinal cord dorsal hom central sensitization （a specific form of synaptic plasticity） that is associated with persistent pain. Recent studies have shown that peripheral inflammation drives changes in ct-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor （AMPAR） subunit trafficking in the dorsal horn and that such changes contribute to the hypersensitivity that underlies persistent pain. Here, we review current evi- dence to illustrate how spinal cord AMPARs participate in the dorsal hom central sensitization associated with persistent pain. Understanding these mechanisms may allow the development of novel therapeutic strategies for treating persistent pain.展开更多
Neuropathic pain is of serious clinical concern and only about half of patients achieve partial relief with currently-available treatments,so it is critical to find new drugs for this condition.Recently,the cellsurfac...Neuropathic pain is of serious clinical concern and only about half of patients achieve partial relief with currently-available treatments,so it is critical to find new drugs for this condition.Recently,the cellsurface trafficking of pain-related receptors has been suggested as an important mechanism underlying persistent neuropathic pain.Here,we used the short peptide GluA_（2-3y）,which specifically inhibits the GluA2-dependent endocytosis of a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors,and tested its anti-nociceptive effect in the periaqueductal grey（PAG） of intact rats and rats with neuropathic pain.Intra-PAG injection of 0.15,1.5,7.5,and 15 pmol of GluA_（2-3y） induced dose-dependent increases in hindpaw withdrawal latencies to noxious thermal and mechanical stimuli in intact rats,suggesting that GluA2 cell-surface trafficking in the PAG is involved in pain modulation.Furthermore,GluA_（2-3y） had much stronger anti-nociceptive effects in rats with neuropathic pain induced by sciatic nerve ligation.Interestingly,the intra-PAG injection of 15 pmol GluA_（2-3y） had an analgesic effect similar to 10 ug（35nmol） morphine in rats with neuropathic pain.Taken together,our results suggested that GluA2 trafficking in the PAG plays a critical role in pain modulation,and inhibiting GluA2 endocytosis with GluA_（2-3y） has potent analgesic effects in rats with neuropathic pain.These findings strongly support the recent hypothesis that targeting receptor trafficking could be a new strategy for the treatment of neuropathic pain.展开更多
基金supported by the National Key R&D Program of China,No.2016YFC1201800(to JFH)the Key Research and Development Program of Hunan Province,Nos.2018SK2090(to JFH),2022SK2079(to JFH)+2 种基金the Natural Science Foundation of Hu nan Province,No.2021JJ30891(to DC)the Human Resource Bank Program of Hunan Province,No.2020TP3003(to JFH)the School-Enterprise Joint Program of Central South University,No.2021XQLH092(to TQD)。
文摘Adipose mesenchymal stem cells(ADSCs)have protective effects against glutamate-induced excitotoxicity,but ADSCs are limited in use for treatment of optic nerve injury.Studies have shown that the extracellular vesicles(EVs)secreted by ADSCs(ADSC-EVs)not only have the function of ADSCs,but also have unique advantages including non-immunogenicity,low probability of abnormal growth,and easy access to target cells.In the present study,we showed that intravitreal injection of ADSC-EVs substantially reduced glutamate-induced damage to retinal morphology and electroretinography.In addition,R28 cell pretreatment with ADSC-EVs before injury inhibited glutamate-induced overload of intracellular calcium,downregulation ofα-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid receptor(AMPAR)subunit GluA2,and phosphorylation of GluA2 and protein kinase C alpha in vitro.A protein kinase C alpha agonist,12-O-tetradecanoylphorbol 13-acetate,inhibited the neuroprotective effects of ADSC-EVs on glutamate-induced R28 cells.These findings suggest that ADSCEVs ameliorate glutamate-induced excitotoxicity in the retina through inhibiting protein kinase C alpha activation.
基金supported by grants from the National Institutes of Health (NS058886 and NS072206)Rita Allen Foundation+1 种基金Mr. David Koch and the Patrick C. Walsh Prostate Cancer Research Fundthe Blaustein Pain Research Fund
文摘Activity-dependent postsynaptic receptor trafficking is critical for long-term synaptic plasticity in the brain, but it is unclear whether this mechanism actually mediates the spinal cord dorsal hom central sensitization （a specific form of synaptic plasticity） that is associated with persistent pain. Recent studies have shown that peripheral inflammation drives changes in ct-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor （AMPAR） subunit trafficking in the dorsal horn and that such changes contribute to the hypersensitivity that underlies persistent pain. Here, we review current evi- dence to illustrate how spinal cord AMPARs participate in the dorsal hom central sensitization associated with persistent pain. Understanding these mechanisms may allow the development of novel therapeutic strategies for treating persistent pain.
基金supported by the National Natural Science Foundation of China (30670658)support from the Minzu University 985 Academic Team-building Fund (YLDX01013, 2015MDTD13C and 25C)the 111 Project of China (B08044)
文摘Neuropathic pain is of serious clinical concern and only about half of patients achieve partial relief with currently-available treatments,so it is critical to find new drugs for this condition.Recently,the cellsurface trafficking of pain-related receptors has been suggested as an important mechanism underlying persistent neuropathic pain.Here,we used the short peptide GluA_（2-3y）,which specifically inhibits the GluA2-dependent endocytosis of a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors,and tested its anti-nociceptive effect in the periaqueductal grey（PAG） of intact rats and rats with neuropathic pain.Intra-PAG injection of 0.15,1.5,7.5,and 15 pmol of GluA_（2-3y） induced dose-dependent increases in hindpaw withdrawal latencies to noxious thermal and mechanical stimuli in intact rats,suggesting that GluA2 cell-surface trafficking in the PAG is involved in pain modulation.Furthermore,GluA_（2-3y） had much stronger anti-nociceptive effects in rats with neuropathic pain induced by sciatic nerve ligation.Interestingly,the intra-PAG injection of 15 pmol GluA_（2-3y） had an analgesic effect similar to 10 ug（35nmol） morphine in rats with neuropathic pain.Taken together,our results suggested that GluA2 trafficking in the PAG plays a critical role in pain modulation,and inhibiting GluA2 endocytosis with GluA_（2-3y） has potent analgesic effects in rats with neuropathic pain.These findings strongly support the recent hypothesis that targeting receptor trafficking could be a new strategy for the treatment of neuropathic pain.
