Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postu...Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postural instability,as a result of the progressive loss of nigrostriatal dopaminergic neurons.In addition to this neuronal cell loss,Parkinson’s disease is characterized by the accumulation of intracellular protein aggregates,Lewy bodies and Lewy neurites,composed primarily of the proteinα-synuclein.Although it was first described almost 200 years ago,there are no disease-modifying drugs to treat patients with Parkinson’s disease.In addition to conventional therapies,non-pharmacological treatment strategies are under investigation in patients and animal models of neurodegenerative disorders.Among such strategies,environmental enrichment,comprising physical exercise,cognitive stimulus,and social interactions,has been assessed in preclinical models of Parkinson’s disease.Environmental enrichment can cause structural and functional changes in the brain and promote neurogenesis and dendritic growth by modifying gene expression,enhancing the expression of neurotrophic factors and modulating neurotransmission.In this review article,we focus on the current knowledge about the molecular mechanisms underlying environmental enrichment neuroprotection in Parkinson’s disease,highlighting its influence on the dopaminergic,cholinergic,glutamatergic and GABAergic systems,as well as the involvement of neurotrophic factors.We describe experimental pre-clinical data showing how environmental enrichment can act as a modulator in a neurochemical and behavioral context in different animal models of Parkinson’s disease,highlighting the potential of environmental enrichment as an additional strategy in the management and prevention of this complex disease.展开更多
Objective Glutamic acid decarboxylase 2(GAD65) is a gamma-aminobutyric acid(GABA) synthetase.This study aimed to construct a recombinant lentivirus-rGAD65(rLV-rGAD65) vector containing the cDNA of rat GAD65(rGA...Objective Glutamic acid decarboxylase 2(GAD65) is a gamma-aminobutyric acid(GABA) synthetase.This study aimed to construct a recombinant lentivirus-rGAD65(rLV-rGAD65) vector containing the cDNA of rat GAD65(rGAD65) and assess its functional activity in vitro and in vivo.Methods cDNA of rGAD65 was amplified by RT-PCR and subcloned into the LV vector,forming the rLV-GFP-rGAD65 plasmid.The recombinant lentivirus particles(rLVrGAD65) were packaged by the LV Helper-Free System and the titer was measured.Primary rat lung fibroblasts were transfected with rLV-rGAD65.The expression of rGAD65 in fibroblasts was detected by immunocytochemistry and western blot and the level of GABA in the medium was assessed by high-performance liquid chromatograph(HPLC).In vivo,rLV-rGAD65 was injected into the subthalamic nucleus(STN) of Sprague-Dawley rats using stereotaxic methods,and rGAD65 protein levels in the STN were assessed by immunohistochemistry and Western blot,while the GABA concentration in the substantia nigra pars reticulata(SNr) was assayed by HPLC.Results The sequence of rGAD65 cDNA was in accord with that in GenBank.The amino-acid sequence of rGAD65 had no mutations and the titer of rLVrGAD65 reached 6.8 × 108/mL.The efficiency of infection of fibroblasts was 80%,and the concentration of GABA in the medium was(48.14 ± 9.35) nmol/L.In vivo,rGAD65 expression was detected in the STN,and the concentration of GABA in the SNr increased from(5.95 ± 1.09) to(12.44 ± 3.79) nmol/g tissue.Conclusion The recombinant LVGFP-rGAD65 vector was successfully constructed.rLV-rGAD65-infected primary fibroblasts in vitro and the expressed rGAD65 catalyzed the formation of GABA from glutamic acid.In vivo,the concentration of GABA in the SNr was increased after rLV-rGAD65 injection into the STN.展开更多
文摘Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postural instability,as a result of the progressive loss of nigrostriatal dopaminergic neurons.In addition to this neuronal cell loss,Parkinson’s disease is characterized by the accumulation of intracellular protein aggregates,Lewy bodies and Lewy neurites,composed primarily of the proteinα-synuclein.Although it was first described almost 200 years ago,there are no disease-modifying drugs to treat patients with Parkinson’s disease.In addition to conventional therapies,non-pharmacological treatment strategies are under investigation in patients and animal models of neurodegenerative disorders.Among such strategies,environmental enrichment,comprising physical exercise,cognitive stimulus,and social interactions,has been assessed in preclinical models of Parkinson’s disease.Environmental enrichment can cause structural and functional changes in the brain and promote neurogenesis and dendritic growth by modifying gene expression,enhancing the expression of neurotrophic factors and modulating neurotransmission.In this review article,we focus on the current knowledge about the molecular mechanisms underlying environmental enrichment neuroprotection in Parkinson’s disease,highlighting its influence on the dopaminergic,cholinergic,glutamatergic and GABAergic systems,as well as the involvement of neurotrophic factors.We describe experimental pre-clinical data showing how environmental enrichment can act as a modulator in a neurochemical and behavioral context in different animal models of Parkinson’s disease,highlighting the potential of environmental enrichment as an additional strategy in the management and prevention of this complex disease.
文摘Objective Glutamic acid decarboxylase 2(GAD65) is a gamma-aminobutyric acid(GABA) synthetase.This study aimed to construct a recombinant lentivirus-rGAD65(rLV-rGAD65) vector containing the cDNA of rat GAD65(rGAD65) and assess its functional activity in vitro and in vivo.Methods cDNA of rGAD65 was amplified by RT-PCR and subcloned into the LV vector,forming the rLV-GFP-rGAD65 plasmid.The recombinant lentivirus particles(rLVrGAD65) were packaged by the LV Helper-Free System and the titer was measured.Primary rat lung fibroblasts were transfected with rLV-rGAD65.The expression of rGAD65 in fibroblasts was detected by immunocytochemistry and western blot and the level of GABA in the medium was assessed by high-performance liquid chromatograph(HPLC).In vivo,rLV-rGAD65 was injected into the subthalamic nucleus(STN) of Sprague-Dawley rats using stereotaxic methods,and rGAD65 protein levels in the STN were assessed by immunohistochemistry and Western blot,while the GABA concentration in the substantia nigra pars reticulata(SNr) was assayed by HPLC.Results The sequence of rGAD65 cDNA was in accord with that in GenBank.The amino-acid sequence of rGAD65 had no mutations and the titer of rLVrGAD65 reached 6.8 × 108/mL.The efficiency of infection of fibroblasts was 80%,and the concentration of GABA in the medium was(48.14 ± 9.35) nmol/L.In vivo,rGAD65 expression was detected in the STN,and the concentration of GABA in the SNr increased from(5.95 ± 1.09) to(12.44 ± 3.79) nmol/g tissue.Conclusion The recombinant LVGFP-rGAD65 vector was successfully constructed.rLV-rGAD65-infected primary fibroblasts in vitro and the expressed rGAD65 catalyzed the formation of GABA from glutamic acid.In vivo,the concentration of GABA in the SNr was increased after rLV-rGAD65 injection into the STN.