A DJ-1 Based Peptide Attenuates Dopaminergic Degeneration in Mice Models of Parkinson's Disease via Enhancing Nrf2
Fig 1
ND-13 attenuates toxicity of trophic factors depletion, oxidative insults and neurotoxins.
SH-SY5Y, human neuroblastoma cells, were exposed to increasing doses of hydrogen peroxide (H2O2, 0–60 μM), 6-OHDA (0–25 μM) or dopamine (0–10 μM) for 24 hours. ND-13 (4 μM) or vehicle were applied 1 hour before the toxic insults. (A) ND-13 attenuated H2O2-induced cell death, measured by LDH cytotoxicity assay and (B) restored H2O2-induced metabolic changes, measured by Alamar blue. As controls we used cells treated with vehicle (phosphate buffered saline) or short peptides (ND-6 and ND-8) with sequences similar to ND-13, attached to the same cell penetrating peptide as ND-13. (C) ND-13 attenuated 6-OHDA and (D) against dopamine toxicity, as measured by the LDH cytotoxicity assay. (E) ND-13 preserved viability of human neuroblastoma cells SH-SY5Y exposed to trophic factors depletion (done by serum deprivation for 48 hours, * p<0.05 as compared to cell culture with serum, # p<0.05 as compared to cell culture without serum or ND-13). (F) ND-13 does not induce cell proliferation. Human neuroblastoma cells (SH-SY5Y) were exposed to 4 μM ND-13 or vehicle for 24 hours. Cell proliferation was quantified by BrdU assay. No significant differences were observed between ND-13 treated cells and vehicle treated cells. Data are presented as means ± S.D. * p<0.05 as compared to cells exposed to vehicle and the same toxic dose. The experiments were repeated 3 times in triplicates.