Quinolinic acid is a product of tryptophan degradation and may serve as a precursor for NAD(+), an important enzymatic cofactor for enzymes such as the DNA repair protein PARP. Pathologic accumulation of quinolinic acid has been found in neurodegenerative disorders including Alzheimer and Huntington disease, where it is thought to be toxic for neurons by activating the N-methyl-D-aspartate (NMD...

Huntington's disease is a chronic neurodegenerative disorder inherited in an autosomal dominant fashion, and characterized as involuntary movement. Quinolinic acid has been used to produce an animal model of Huntington's disease. In the present study, the effect of treadmill exercise on spatial-learning ability and motor coordination focusing on the apoptosis in the hippocampus was investigated...

The effect of kainic and quinolinic acid on cortical cholinergic function was examined following injections of these agents into the nucleus basalis magnocellularis (nbm) or into the frontoparietal cortex. The release of cortical 3H-acetylcholine (3H-ACh), high affinity choline uptake (HACU) and acetylcholinesterase was measured 7 days following injections of saline (control), kainic acid (4.7 ...

Quinolinic acid, a macrophage/microglia-derived excitotoxin fulfills a plethora of functions such as neurotoxin, gliotoxin, and proinflammatory mediator, and it alters the integrity and cohesion of the blood-brain barrier in several pathophysiological states. Beta-trace protein (BTP), a monomeric glycoprotein, is known to indicate cerebrospinal fluid leakage. Thus, the prior aim of this study w...

Since the observation (1) that tryptophan and nicotinic acid are mutually interchangeable, within limits, in supporting the growth of rats, considerable evidence has accumulated which indicates that biosynthesis of nicotinic acid can proceed from tryptophan (2-5). Unequivocal evidence for this transformation was provided by the experiments of Heidelberger et al. (6) who fed labeled tryptophan @...

Melinacidin, a new antibacterial agent, blocked the synthesis of nicotinic acid and its amide in Bacillus subtilis cells. The inhibitory activity of the agent was reversed by nicotinic acid, its amide, or nicotinamide adenine dinucleotides, but not by l-kynurenine, l-3-hydroxykynurenine, l-hydroxyanthranilic acid, or quinolinic acid. These properties indicated that the antibiotic interferes wit...

1. Nicotinylalanine, an inhibitor of kynurenine metabolism, has been shown to elevate brain levels of endogenous kynurenic acid, an excitatory amino acid receptor antagonist. This study examined the potential of nicotinylalanine to influence excitotoxic damage to striatal NADPH diaphorase (NADPH-d) and gamma-aminobutyric acid (GABA)ergic neurones that are selectively lost in Huntington's diseas...

Huntington's Disease (HD) is a common neurodegenerative disorder characterized by motor disturbances, subcortical dementia and psychiatric disturbances. Pathogenesis of HD revolves so far around excitatory amino acids as the primary cause of neuronal loss. However, number of recent reports suggests the involvement of excitotoxicity and oxidative damage. In the present study, first the dose of q...

BACKGROUND The aim of this exploratory study is to gain for the first time a more comprehensive picture of the impact of changes of quinolinic acid concentrations on depressive symptomatology during and after IFN-α therapy. METHODS The quinolinic acid concentrations of 35 HCV patients are examined in a prospective survey over the entire period of IFN-α treatment as well as three months later ...