Synphilin-1 exhibits trophic and protective effects against Rotenone toxicity

Neuroscience. 2010 Jan 20;165(2):455-62. doi: 10.1016/j.neuroscience.2009.10.042.

Abstract

Synphilin-1 is a cytoplasmic protein with unclear function. Synphilin-1 has been identified as an interaction partner of alpha-synuclein. The interaction between synphilin-1 and alpha-synuclein has implications in Parkinson's disease. In this study, we stably overexpressed human synphilin-1 in mouse N1E-115 neuroblastoma cells. We found that overexpression of synphilin-1 shortened cell growth doubling time and increased neurite outgrowth. Knockdown of endogenous synphilin-1 caused neuronal toxicity and shortened neurite outgrowth. We further found that synphilin-1 increased activation of the extracellular signal-regulated kinases (ERK1/2) and mediated neurite outgrowth. Rotenone, mitochondrial complex I inhibitor, has been shown previously to induce dopaminergic neurodegeneration and Parkinsonism in rats and Drosophila. We found that Rotenone induced apoptotic cell death in N1E-115 cells via caspase-3 activation and poly (ADP-ribose) polymerase (PARP) cleavage. Overexpression of synphilin-1 significantly reduced Rotenone-induced cell death, caspase-3 activation and PARP cleavage. The results indicate that synphilin-1 displays trophic and protective effects in vitro, suggesting that synphilin-1 may play a protective role in Parkinson's disease (PD) pathogenesis and may lead to a potential therapeutic target for PD intervention.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects*
  • Apoptosis / physiology
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Caspase 3 / metabolism
  • Cell Enlargement
  • Cell Line, Tumor
  • Cell Proliferation
  • Electron Transport Complex I / antagonists & inhibitors*
  • Gene Knockdown Techniques
  • Humans
  • Intracellular Signaling Peptides and Proteins
  • Mice
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase 3 / metabolism
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Neurites / physiology
  • Neurons / drug effects*
  • Neurons / physiology
  • Poly (ADP-Ribose) Polymerase-1
  • Poly(ADP-ribose) Polymerases / metabolism
  • Rotenone / pharmacology*
  • Time Factors
  • Transfection

Substances

  • Carrier Proteins
  • Intracellular Signaling Peptides and Proteins
  • Nerve Tissue Proteins
  • SNCAIP protein, human
  • Sncaip protein, mouse
  • Rotenone
  • Parp1 protein, mouse
  • Poly (ADP-Ribose) Polymerase-1
  • Poly(ADP-ribose) Polymerases
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • Casp3 protein, mouse
  • Caspase 3
  • Electron Transport Complex I