Three rats of six males, surviving 22 to 27.5 months after one or two intragastric doses of the monoester pyrrolizidine alkaloid, heliotrine (230 mg/kg body weight), and pretreatment with nicotinamide (350 mg/kg body weight) by pretreatment with nicotinamide (350 mg/kg body weight) by i.p. injections, developed pancreatic islet-cell tumors, accompanied in one of the rats by transitory cell papi...

The uptake and metabolism of nicotinic acid, nicotinamide, and quinolinic acid at physiological concentrations by perfused rat liver have been studied. At a level of 400 mpmoles per liver, nicotinic acid was a more effective precursor of NAD than was nicotinamide. Labeled NAD in the liver reached maximum levels 10 min after nicotinic acid was added to the perfusate. When nicotinamide was the su...

Phorbol ester-induced promotion of initiated NMRI mouse skin keratinocytes to papillomas could be largely prevented when nicotinamide-like inhibitors of poly(ADP-ribose)polymerase (nicotinamide, benzamide, 3-aminobenzamide) were applied simultaneously with 12-O-tetradecanoylphorbol-13-acetate (TPA). A similar suppression of tumor promotion by nicotinamide analogues was demonstrated in clone 41 ...

Nicotinamide containing cofactors are ubiquitous in biological systems. As a result, when studying nicotinamide dependent systems in vitro or in vivo, isotopically labeled nicotinamide cofactors are often used to reveal the mechanism of the biological system of interest. The reduced form of these cofactors is labile and is sensitive to light, oxygen, pH, temperature and other factors. Consequen...

The purpose of the present study was to examine the ability of nicotinamide to prevent the appearance of neurobehavioral symptoms induced by 3-acetyl pyridine (3-AP) in rats. Nicotinamide in doses of 5,50 and 500 mg/kg was injected immediately after administration of 65 mg/kg 3-AP, and neurobehavioral measurements were made at 6, 12, 24, 48 and 72 hours after injections. The effects of 500 mg/k...

Sir2 enzymes are broadly conserved from bacteria to humans and have been implicated to play roles in gene silencing, DNA repair, genome stability, longevity, metabolism, and cell physiology. These enzymes bind NAD(+) and acetyllysine within protein targets and generate lysine, 2'-O-acetyl-ADP-ribose, and nicotinamide products. To provide structural insights into the chemistry catalyzed by Sir2 ...

Because of its relatively indolent clinical course, chronic lymphocytic leukemia (CLL) offers a versatile model for testing novel therapeutic regimens and drug combinations. Nicotinamide is the main NAD(+) precursor and a direct inhibitor of four classes of enzymes, including the sirtuins. SIRT1, the main member of the sirtuin family, inactivates p53 by deacetylating a critical lysine residue. ...

Hydrogen bonds and halogen bonds operate in concert in the directed assembly of infinite 1-D chains in binary co-crystals of iodine iso-nicotinamide (2 : 2), 1 and tetrafluorodiiodobenzene iso-nicotinamide (1 : 2) 2.

A patient with severe malabsorption due to massive diverticulosis of the small intestine developed an acute encephalopathic syndrome which responded dramatically to intravenous nicotinamide. Various mechanisms are discussed whereby nicotinamide deficiency might have occurred in this clinical context.

INTRODUCTION Vitamin B3 has been shown to play an important role during embryogenesis. Specifically, there is growing evidence that nicotinamide, the biologically active form of vitamin B3, plays a critical role as a morphogen in the differentiation of stem cells to mature cell phenotypes, including those of the central nervous system (CNS). Detailed knowledge of the action of small molecules d...