The basic helix-loop-helix(bHLH)transcription factor,DEC1,provides neuroprotection from apoptosis induced by MPP^+ through PI3K/Akt pathway in SHSY5Y cells

OBJECTIVE To determine the role of the basic helix-loop-helix(b HLH)transcription factor,differentiated embryonic chondrocyte gene 1(DEC1),in the apoptosis induced by 1-methyl-4-phenylpyridiniumion(MPP+)in SH-SY5Y cells.METHODS SH-SY5Y cells were treated with different concentrations of MPP+for 24or 48 h.The cell inhibition and apoptosis were measured by MTT and DAPI staining.DEC1,the apoptosis-related proteins and PI3K/Akt/GSK3β/β-catenin signaling were determined by Western blotting.The expression of DEC1was regulated by overexpression and sh RNA.RESULTS MPP+induces apoptosis along with decreasing of DEC1expression in SH-SY5Y cells.Overexpression or knockdown of DEC1 can alleviate or enhance the cell inhibition induced by MPP+.And overexpression of DEC1 can alleviate the increased cleaved caspase 3/caspase 3 but not alleviate Bax/Bcl-2 induced by MPP+.Meanwhile,MPP+represses PI3Kp110α,p-Akt/Akt,p-GSK-3β/GSK-3βandβ-catenin expression,which is accompanied by decreasing DEC1 expressions.It is confirmed that the activator or inhibitor of PI3K/Akt/GSK-3βpathway can alleviate or enhance the repression of PI3K/Akt/GSK3β/β-catenin signaling cascade induced by MPP+.Further study,we find that overexpression of DEC1 alone can increase PI3Kp110α,p-Akt/Akt,p-GSK-3β/GSK-3β,andβ-catenin expression.More importantly,overexpression of DEC1 significantly alleviates the decreased levels of PI3Kp110α,p-Akt/Akt,p-GSK-3β/GSK-3β,andβ-catenin induced by MPP+.CONCLUSION DEC1 provides neuroprotection from apoptosis induced by MPP+through PI3K/Akt pathway in SH-SY5Y cells.Promisingly,DEC1 is a candidate gene that may provide a novel therapeutic approach for the treatment of Parkinson disease.