RESUMEN
<p><b>OBJECTIVE</b>The neuroprotective effect of erythropoietin (EPO) against 1-methyl-4-phenylpyridinium (MPP(+))-induced oxidative stress in cultured PC12 cells, as well as the underlying mechanism, were investigated.</p><p><b>METHODS</b>PC12 cells impaired by MPP(+) were used as the cell model of Parkinson's disease. Methyl thiazolyl tetrazolium (MTT) was used to assay the viability of the PC12 cells exposed to gradient concentrations of EPO, and the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay was used to analyze the apoptosis ratio of PC12 cells. The expression of Bcl-2 and Bax in PC12 cells were examined by Western blot, and the reactive oxygen species (ROS), the mitochondrial transmembrane potential and the activity of caspase-3 in each group were detected by spectrofluorometer.</p><p><b>RESULTS</b>Treatment of PC12 cells with MPP(+) caused the loss of cell viability, which may be associated with the elevation in apoptotic rate, the formation of ROS and the disruption of mitochondrial transmembrane potential. It was also shown that MPP(+) significantly induced the upregulation of Bax/Bcl-2 ratio and the activation of caspase-3. In contrast, EPO significantly reversed these responses and had the maximum protective effect at 1 U/mL.</p><p><b>CONCLUSION</b>The inhibitive effect of EPO on the MPP(+)-induced cytotoxicity may be ascribed to its anti-oxidative property and anti-apoptotic activity, and EPO may provide a useful therapeutic strategy for treatment of neurodegenerative diseases such as Parkinson's disease.</p>
Asunto(s)
Animales , Ratas , 1-Metil-4-fenilpiridinio , Toxicidad , Análisis de Varianza , Apoptosis , Caspasa 3 , Metabolismo , Supervivencia Celular , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Eritropoyetina , Farmacología , Citometría de Flujo , Métodos , Herbicidas , Toxicidad , Etiquetado Corte-Fin in Situ , Métodos , Potencial de la Membrana Mitocondrial , Fármacos Neuroprotectores , Farmacología , Células PC12 , Proteínas Proto-Oncogénicas c-bcl-2 , Genética , Metabolismo , Especies Reactivas de Oxígeno , Metabolismo , Sales de Tetrazolio , Tiazoles , Proteína X Asociada a bcl-2 , Genética , MetabolismoRESUMEN
Objective To observe the activating effect of ciliary neurotrophic factor (CNTF) on astrocyte in vitro. Methods Astrocytes cultured purely from newborn rats. Cerebral cortex was raised in normal and serum deprivation condition with different concentrations (in ng/ml: 0, 2, 20, or 200) of CNTF. After cultured for 24 h, the shape and the cell cycle of astrocytes were examined by immunocytochemistry and flow cytometer, respectively. Results The immunoactivity of glial fibrillary acidic protein (GFAP) and the nuclear size of astrocytes were increased when CNTF was applied, whether cells were cultured in medium with or without serum. CNTF promoted astrocytes to enter the cell cycle in medium with serum, but had no this effect in medium without serum. Conclusion In medium without serum, astrocytes could differentiate into activated state cells with CNTF application, but could not proliferate; in medium with serum, astrocytes could proliferate with aid of CNTF.