Premium
A Redox Insensitive Triple Cysteine Mutant of SirT1 Rescues Oxidative Stress induced Apoptosis
Author(s) -
Shao Di,
Fry Jessica,
Zee Rebecca,
Kumar Vikas,
Pimentel David,
Cohen Richard,
Bachschmid Markus
Publication year - 2013
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.27.1_supplement.993.2
Subject(s) - oxidative stress , nad+ kinase , sirtuin 1 , chemistry , acetylation , apoptosis , sirtuin , oxidative phosphorylation , histone deacetylase , hek 293 cells , inflammation , histone , microbiology and biotechnology , biochemistry , biology , enzyme , downregulation and upregulation , immunology , gene
Sirtuin 1 (SirT1) is a NAD + ‐dependent class III histone deacetylase that orchestrates cell cycle progression, energy metabolism and aging. SirT1 activity is modulated by [NAD + ]/[NADH] ratio and post translational modifications. Oxidative stress is a hallmark of metabolic disease and inflammation that contributes to the progression of pathology in part through oxidative post‐translational modification (OPTM) of proteins. HepG2 (liver carcinoma) and HEK293 (transformed embryonic kidney) cells were treated with increasing levels of oxidants (H 2 O 2 , Cys‐NO) or high palmitate high glucose (HPHG) to mimic conditions of metabolic disease. We found that SirT1 activity was inhibited without change in protein expression in both an activity assay and by p53 acetylation measured by western and by PUMA luciferase activity. The oxidant‐induced increase in apoptosis was ameliorated by overexpression of a mutant SirT1 that cannot be oxidized on three critical cysteine thiols that we found are reversibly modified by HPHG, Cys‐NO and H 2 O 2 , suggesting that thiol oxidation on SirT1 in metabolic disease contributes to pathology. NIH PO1 HL 068758, R37 HL104017 ; NHLBI HHSN268201000031C