Nicotinamide adenine dinucleotide (NAD(+)) is an endogenous enzyme cofactor and cosubstrate that has effects on diverse cellular and physiologic processes, including reactive oxygen species generation, mitochondrial function, apoptosis, and axonal degeneration. A major goal is to identify the NAD(+)-regulated cellular pathways that may mediate these effects. Here we show that the dynamic assemb...

Sirtuins are critical players within multiple cellular pathways such as stress response, apoptosis and energy metabolism. They are associated with metabolic and degenerative diseases, the pathogenesis of cancer and are key elements in the regulation of cellular life span. From within the 7 known human sirtuins, SIRT3 recently stepped out of the shadow of SIRT1 showing strong effects on stress r...

SIRT3 and SIRT5 have been shown to regulate mitochondrial fatty acid oxidation but the molecular mechanisms behind the regulation are lacking. Here, we demonstrate that SIRT3 and SIRT5 both target human very long-chain acyl-CoA dehydrogenase (VLCAD), a key fatty acid oxidation enzyme. SIRT3 deacetylates and SIRT5 desuccinylates K299 which serves to stabilize the essential FAD cofactor in the ac...

Dear Sir, We read with interest the recent article by Toledo et al. [1]. In their study, the authors found that mRNA levels for SIRT1 were increased in muscle from tumor-bearing rats and that SIRT3mRNA levels were unchanged. In the discussion of the results, the authors stated that the observation of unchanged SIRT3 “is in contrast with that of Alamdari et al. [39] showing an upregulation of SI...

August 9, 2016 e77 CORRPONDENCE CORRPONDENCE To the Editor: We read with interest the article by Lai and coworkers1 published in Circulation about the favorable cardiovascular and metabolic effects of inorganic nitrite and metformin in patients with pulmonary hypertension in heart failure with preserved ejection fraction. Accumulating studies have demonstrated the therapeutic effects of stimula...

Nicotinamide phosphoribosyltransferase (NAMPT) catalyzes the rate-limiting step of nicotinamide adenine dinucleotide (NAD(+)) synthesis. NAMPT expression promotes angiogenesis, DNA synthesis, cell growth and survival, and mitochondrial biogenesis and function. Sirtuin-3 (SIRT3) is an NAD(+)-dependent deacetylase which functions in conjunction with mitochondrial NAMPT to promote cell survival fo...

SIRT3, SIRT4, and SIRT5 are mitochondrial deacylases that impact multiple facets of energy metabolism and mitochondrial function. SIRT3 activates several mitochondrial enzymes, SIRT4 represses its targets, and SIRT5 has been shown to both activate and repress mitochondrial enzymes. To gain insight into the relative effects of the mitochondrial sirtuins in governing mitochondrial energy metaboli...

The escalating prevalence of the metabolic syndrome has coincided with the emergence of a lifestyle that replaces physical activity with overindulgence. In this setting, excess nutrients continuously bombard the major metabolic organs, leaving resident cells to cope with a steady influx of superfluous carbon fuel. The molecular consequences of energy surplus are far-reaching. Among these, growi...

PURPOSE The sirtuin gene family has been linked with tumourigenesis, in both a tumour promoter and suppressor capacity. Information regarding the function of sirtuins in pancreatic cancer is sparse and equivocal. We undertook a novel study investigating SIRT1-7 protein expression in a cohort of pancreatic tumours. The aim of this study was to establish a protein expression profile for SIRT1-7 i...

Recovered blood supply after cerebral ischemia for a certain period of time fails to restore brain function, with more severe dysfunctional problems developing, called cerebral ischemia-reperfusion injury (CIR). CIR involves several extremely complex pathophysiological processes in which the interactions between key factors at various stages have not been fully elucidated. Mitochondrial dysfunc...