The precise role of neural plasticity under pathological conditions remains not well understood. It appears to be well accepted, however, that changes in the ability of neurons to express plasticity accompany neurolog...The precise role of neural plasticity under pathological conditions remains not well understood. It appears to be well accepted, however, that changes in the ability of neurons to express plasticity accompany neurological diseases. Here, we discuss recent experimental evidence, which suggests that synaptic plasticity induced by a pathological stimulus, i.e., ischemic long-term-potentiation(i LTP) of excitatory synapses, could play an important role for post-stroke recovery by influencing the post-lesional reorganization of surviving neuronal networks.展开更多
Inflammation and coagulation are tightly interconnected in the pathophysiology of neuronal diseases.Thrombin,a pro-coagulant serine protease is associated with neurodegeneration and its indirect inhibitor,activated pr...Inflammation and coagulation are tightly interconnected in the pathophysiology of neuronal diseases.Thrombin,a pro-coagulant serine protease is associated with neurodegeneration and its indirect inhibitor,activated protein C(aPC),is considered neuroprotective.While levels of thrombin and aPC activity are readily measured in the blood,similar assays in the cerebrospinal fluid(CSF)have not been described.The aim of this study was to establish a specific and sensitive enzymatic assay to measure both thrombin and aPC activity in the CSF.CSF was collected from 14 patients with suspected normal pressure hydrocephalus served as a control group,while seven patients with central nervous system infections served as an acute neuro-inflammatory study group and one sample of CSF following traumatic lumbar puncture served as a positive control.Thrombin and aPC activities were measured by fluorescence released by specific proteolytic cleavage in the presence of endopeptidase and amino-peptidase inhibitors to ensure specificity.Specificity of the method was verified by thrombin and serine-protease inhibitors N-alpha-((2-naphthylsulfinyl)glycyl)-DL-p-amidinophenylalanylpiperidine and phenylmethanesulfonyl fluoride.Inhibition of thrombin activity by CSF samples and levels of specific thrombin inhibitors were also assessed.Thrombin and aPC activities were reliably measured and were significantly higher in the CSF of patients with central nervous system infections compared to normal pressure hydrocephalus controls,suggesting the involvement of these factors in neuro-inflammation.CSF thrombin activity levels in the presence of known thrombin concentration were high in patients with central nervous system infections,and low in normal pressure hydrocephalus patients.Quantification of endogenous thrombin inhibitors protease nexin 1,amyloid precursor protein and anti-thrombin III in CSF by western blot indicated a significant elevation of amyloid precursor protein in infectious CSF.In conclusion,this study describes a novel and sensitive assay aimed at the detection of thrombin and aPC activity in CSF.This method may be useful for measuring these factors that reflect degenerative and protective influences of coagulation on neurological disorders.The study procedure was approved by the Ethics Committee of the Chaim Sheba Medical Center(approval No.4245-17-SMC)on October 18,2018.展开更多
基金supported by German Israeli Foundation(G-1317-418.13/2015 to AV and NM)
文摘The precise role of neural plasticity under pathological conditions remains not well understood. It appears to be well accepted, however, that changes in the ability of neurons to express plasticity accompany neurological diseases. Here, we discuss recent experimental evidence, which suggests that synaptic plasticity induced by a pathological stimulus, i.e., ischemic long-term-potentiation(i LTP) of excitatory synapses, could play an important role for post-stroke recovery by influencing the post-lesional reorganization of surviving neuronal networks.
文摘Inflammation and coagulation are tightly interconnected in the pathophysiology of neuronal diseases.Thrombin,a pro-coagulant serine protease is associated with neurodegeneration and its indirect inhibitor,activated protein C(aPC),is considered neuroprotective.While levels of thrombin and aPC activity are readily measured in the blood,similar assays in the cerebrospinal fluid(CSF)have not been described.The aim of this study was to establish a specific and sensitive enzymatic assay to measure both thrombin and aPC activity in the CSF.CSF was collected from 14 patients with suspected normal pressure hydrocephalus served as a control group,while seven patients with central nervous system infections served as an acute neuro-inflammatory study group and one sample of CSF following traumatic lumbar puncture served as a positive control.Thrombin and aPC activities were measured by fluorescence released by specific proteolytic cleavage in the presence of endopeptidase and amino-peptidase inhibitors to ensure specificity.Specificity of the method was verified by thrombin and serine-protease inhibitors N-alpha-((2-naphthylsulfinyl)glycyl)-DL-p-amidinophenylalanylpiperidine and phenylmethanesulfonyl fluoride.Inhibition of thrombin activity by CSF samples and levels of specific thrombin inhibitors were also assessed.Thrombin and aPC activities were reliably measured and were significantly higher in the CSF of patients with central nervous system infections compared to normal pressure hydrocephalus controls,suggesting the involvement of these factors in neuro-inflammation.CSF thrombin activity levels in the presence of known thrombin concentration were high in patients with central nervous system infections,and low in normal pressure hydrocephalus patients.Quantification of endogenous thrombin inhibitors protease nexin 1,amyloid precursor protein and anti-thrombin III in CSF by western blot indicated a significant elevation of amyloid precursor protein in infectious CSF.In conclusion,this study describes a novel and sensitive assay aimed at the detection of thrombin and aPC activity in CSF.This method may be useful for measuring these factors that reflect degenerative and protective influences of coagulation on neurological disorders.The study procedure was approved by the Ethics Committee of the Chaim Sheba Medical Center(approval No.4245-17-SMC)on October 18,2018.