Overexpression Of Pgc-1α Influence Mitochondrial Signal Transduction Of Dopaminergic Neurons

BackgroundParkinson’s disease is a common neurodegenerative disease in the elderly.Mitochondrial dysfunction plays an important role in the pathogenesis of PD. There are many factors involved in the pathogenesis of PD, include environmental and genetic aspects, and mitochondrial dysfunction is a common pathway. PGC-1α( peroxisome proliferator-activated receptor 1 alpha) is a powerful transcription factor which interactive with multiple transcription factors,such as ERRα, NRF-1/NRF-2.PGC-1α widely involves in regulation of mitochondrial biogenesis, oxidative stress,cell metabolism and gene expression through enhancing activity of transcription factors and / or promoting their expression.Currently there are partly research on the role of PGC-1α in the PD. And the effect of PGC-1α signal transduction on biological activity of mitochondria in PD is unclear.ObjectiveTo research the overexpression of PGC-1α to protect SH-SY5 Y cells from mitochondrial damage induced by MPP+, and analyzing it’s signal transduction mechanisms.Methods1. Establishment of cell model: according to the optimal Adenovirus infection coefficient(MOI=100) and the concentration of MPP+(1000μmol/L) from early experiments, we establish the cell model of overexpression and PD.2. To detect the expression level of PGC-1α in each experimental group by Western blot and Real-time PCR.3. To detect the content of cytochrome C from cytoplasm and mitochondria of SH-SY5 Y cell by ELISA.4. To detect the expression level of ERRα, NRF-1 and NRF-2 by Western blot.5. To observe distribution of PGC-1α in SH-SY5 Y cell in normal condition and MPP+ intervention by Fluorescence confocal.Results1.The result of Western blot and Real-time PCR found that protein level and transcription level of PGC-1α in overexpression group are Significantly higher than Ad-GFP group and blank control group, realizing the overexpression of PGC-1α in SH-SY5 Y cells.2.The content of cytochrome C by ELISA display that pretreatment of PGC-1αoverexpression could reduce release of cytochrome C from the mitochondrial to cytosol in SH-SY5 Y cell.3.The result of Western blot show that the trend of protein level of ERRα and NRF-1and are consist with the trend of PGC-1α, but the protein level of NRF-2 in the presence of MPP+ and overexpression groups has no obvious change.4.The result of Fluorescence confocal shows that under normal circumstances,PGC-1α almost distributed in nucleus of SH-SY5 Y cell; while in the gradually increasing concentration of MPP+, PGC-1α is gradually appeared by microdose in the cytoplasm of SH-SY5 Y cell.Conclusions1.In this experiment, the cellular damaged by MPP+ was used as the model for PD,which is a traditional PD external model. adenovirus has a higher infection rate of SH-SY5 Y cell, Ad-GFP-PGC-1α adenovirus realizes the high expression of PGC-1αin SH-SY5 Y cell, and provide experimental basis for further study of effect on PGC-1α in PD cell model.2.Overexpression of PGC-1α can promote the stability of mitochondrial membrane,and reduce the release of cytochrome C to resist oxidative stress on mitochondrial damage induced by MPP+.3.The increasing expression of PGC-1α promotes the expression of nuclear transcription factors ERRα and NRF-1. According to the result, we can conclude that the PGC-1α may reduce oxidative stress damage induced by MPP+ mainly through the ERRα and NRF-1 pathway.