title: Low molecular weight thiol amides attenuate MAPK activity and protect primary neurons from Abeta(1-42) toxicity.
abstract: Oxidative stress caused by various stimuli lead to oxidation of glutathione (GSH), the major redox power of the cell. Amyloid beta [Abeta(1-42)] is one of the key components of senile plaques and is involved in the progress initiation and triggers of Alzheimer's disease (AD). Lower GSH levels correlated with the activation of mitogen-activated proteins kinases (MAPK) have been demonstrated in AD, Parkinson's disease (PD) and other neurodegenerative disorders and have been proposed to play a central role in the deterioration of the aging and neurodegenerative brain. In this study, we evaluated the ability of low molecular weight thiol amides, N-acetyl cysteine amide (AD4) that replenishes GSH levels, N-acetyl glycine cysteine amide (AD7) and N-acetyl-Cys-Gly-Pro-Cys-amide (CB4) to protect primary neuronal culture against the oxidative and neurotoxic effects of Abeta(1-42) and to inhibit cisplatin- and hydrogen-peroxide-induced phosphorylation of two MAP kinases (MAPK), p38 and ERK1/2, in NIH3T3 cells. Cell death induced by Abeta(1-42) in primary neuronal cells was reversed by the thiol amides. Likewise, protein oxidation, loss of mitochondrial function and DNA fragmentation all returned to control levels by pretreatment with the three thiol amides. Elevated phosphorylation of ERK1/2 and p38 induced by cisplatin or H2O2 in NIH3T3 cells was lowered by AD4, AD7 and CB4 in a dose-dependent manner. Taken together, these results suggest that the thiol amides AD4, AD7 and CB4 protect neuronal cells against Abeta(1-42) toxicity by attenuating oxidative stress in correlation with inhibiting the MAPK phosphorylation cascade. These results are consistent with the notion that these small molecular thiol amides may play a viable protective role in the oxidative and neurotoxicity induced by Abeta(1-42) in AD brain.
authors.affiliation: Department of Biological Chemistry, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: Orit
authors.initials: O
authors.lastname: Bartov
authors.forename: Rukhsana
authors.initials: R
authors.lastname: Sultana
authors.forename: D Allan
authors.initials: DA
authors.lastname: Butterfield
authors.forename: Daphne
authors.initials: D
authors.lastname: Atlas
mesh_terms: D000111:Acetylcysteine / Q000031:analogs & derivatives / Q000494:pharmacology; D000577:Amides / Q000494:pharmacology*; D016229:Amyloid beta-Peptides / Q000037:antagonists & inhibitors / Q000633:toxicity*; D000818:Animals; D000831:Animals, Newborn; D015153:Blotting, Western / Q000379:methods; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D004151:Dipeptides / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D016166:Free Radical Scavengers / Q000494:pharmacology*; D005978:Glutathione / Q000031:analogs & derivatives; D015227:Lipid Peroxidation / Q000187:drug effects; D051379:Mice; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism*; D008970:Molecular Weight; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D009842:Oligopeptides / Q000494:pharmacology; D010084:Oxidation-Reduction / Q000187:drug effects; D010446:Peptide Fragments / Q000037:antagonists & inhibitors / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013778:Tetrazolium Salts; D013844:Thiazoles; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: D000577:Amides; D016229:Amyloid beta-Peptides; D004151:Dipeptides; D016166:Free Radical Scavengers; C510898:N-acetyl glycine cysteine amide; C510899:N-acetyl-Cys-Gly-Pro-Cys-amide; D009842:Oligopeptides; D010446:Peptide Fragments; D013778:Tetrazolium Salts; D013844:Thiazoles; C075222:amyloid beta-protein (1-42); C002744:3-nitrotyrosine; D014443:Tyrosine; C487056:N-Acetylcysteinamide; D020929:Mitogen-Activated Protein Kinase Kinases; C022616:thiazolyl blue; D005978:Glutathione; D000111:Acetylcysteine