RESUMO
BACKGROUND: Depression is a common disease that endangers people's physical and mental health. Traditional Chinese medicine has advantages in treating the emotional and cognitive symptoms of depressive disorders. OBJECTIVE: To study the effects of baicalin on the behavior and to clarify the underlying mechanism through evaluation of the Rac1-LIMK1-cofilin pathway. METHODS: A chronic mild stress (CMS) model of depression was used. Baicalin was administered to the mice for the intervention, and the positive control group was treated with fluoxetine. Behavioral tests were conducted to observe the degree of depressive disorders. Synaptophysin (SYP), postsynaptic density protein-95 (PSD95), brain-derived neurotrophic factor (BDNF), tyrosine kinase receptors (TrkB), Rac1 and cofilin expression was determined using Western blot analysis, and mRNA was quantified using real-time PCR. RESULTS: Mice in the CMS group showed an increase in depression-like behavior (p < 0.01), while mice in the baicalin and fluoxetine groups showed a decrease in depression-like behavior (p < 0.01), compared with the control group. Electron microscopy showed ultrastructural changes in the hippocampal CA3 area of the CMS group, which were alleviated by baicalin treatment. SYP, PSD95, BDNF, TrkB, Rac1 and cofilin protein expression levels were decreased in the CMS group compared with the control group, while these levels were increased in the baicalin and fluoxetine groups (p < 0.01). There was no significant difference among the baicalin and fluoxetine groups (p > 0.05). CONCLUSION: Baicalin markedly alleviated depression-like behavioral changes, exerted effects on SYP, PSD95, BDNF, and TrkB expression, activated the Rac1-cofilin pathway, and subsequently improve synaptic plasticity.
Assuntos
Fatores de Despolimerização de Actina/metabolismo , Comportamento Animal , Depressão/tratamento farmacológico , Flavonoides/uso terapêutico , Quinases Lim/metabolismo , Transdução de Sinais , Estresse Psicológico/tratamento farmacológico , Proteínas rac de Ligação ao GTP/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Doença Crônica , Depressão/complicações , Proteína 4 Homóloga a Disks-Large/genética , Proteína 4 Homóloga a Disks-Large/metabolismo , Flavonoides/química , Flavonoides/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/ultraestrutura , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Neurônios/ultraestrutura , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor trkB/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estresse Psicológico/complicações , Natação , Sinaptofisina/genética , Sinaptofisina/metabolismoRESUMO
Considerable evidence indicates that methionine sulfoxide (MetO) reductase A (MsrA) plays an important role in cytoprotection against oxidative stress and serves as a potential drug target. To screen for MsrA regulators, a rapid and specific assay to monitor MsrA activity is required. Most of current assays for MsrA activity are based on the reduction of radioactive substrates such as [3H]-N-acetyl-MetO or fluorescent derivatives such as dimethylaminoazo-benzenesulfonyl-MetO. However, these assays require extraction procedures and special instruments. Here, we developed a specific colorimetric microplate assay for testing MsrA activity quickly, which was based on the fact that MsrA can catalyze the reduction of methyl sulfoxides and simultaneously oxidize dithiothreitol (DTT), whose color can be produced by reacting with Ellman's reagent (dithio-bis-nitrobenzoic acid, DTNB). The corresponding absorbance change at 412nm was recorded with a microplate reader as the reaction proceeded. This method to monitor MsrA activity is easy to handle. Our findings may serve as a rapid method for the characterization of recombinant enzyme and for the screening of enzyme inhibitors, pharmacological activators, gene expression regulators and novel substrates.
Assuntos
Colorimetria/métodos , Oxirredutases/metabolismo , Animais , Ácido Ditionitrobenzoico , Ditiotreitol/metabolismo , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Estresse Oxidativo , Oxirredutases/antagonistas & inibidores , Oxirredutases/genética , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectrofotometria , Especificidade por Substrato , Sulfóxidos/metabolismoRESUMO
More and more attention in the field of drug discovery has been focused on the neuroprotection of natural compounds from traditional medicinal herbs. Cerebral ischemia is a complex pathological process involving a series of mechanisms, and a framework for the development of neuroprotectants from traditional herb medicine is a promising treatment for cerebral ischemia. Natural compounds with the effects of anti-oxidation, anti-inflammation, calcium antagonization, anti-apoptosis, and neurofunctional regulation exhibit preventive or therapeutic effects on experimental ischemic brain injury. According to the pharmacological mechanisms underlying neuroprotection, we evaluated natural products from traditional medicinal herbs that exhibit protective effects on ischemic brain injury and characterized the promising targets.