Indoleamine 2,3-dioxygenesae-1 (IDO-1) catalyses the initial, rate-limiting step in tryptophan metabolism, thereby regulating tryptophan availability and the formation of downstream metabolites, including picolinic and quinolinic acid. We found that Mycobacterium tuberculosis infection induced marked upregulation of IDO-1 expression in both human and murine macrophages in vitro and in the lungs...

It has been known for many years that tryptophan is converted to niacin by mammals (1) and Neurospora (2) and that 3-hydroxyanthranilate is an intermediate in this conversion (3). The steps between 3-hydrosyanthranilate and niacin have, homever, remained obscure until recently. A very active soluble oxidase present in mammalian kidney and liver converts 3-hydroxyanthranilate to the unstable acy...

We recently reported the use of a chronic dialytic delivery system for intrastriatal administration of quinolinic acid in the rat.” This system produces ~~~e~ration with some characteristics simihtr to posf ntortem brain tissue from Hun~on’s disease patients, including reduced cytochrome oxidase staining, a decreased number of Nissl-stained neurons, and relative sparing of striatal NADPH-diapho...

Previous studies have shown that basal forebrain lesions using different excitotoxins produce similar decreases in cortical choline acetyltransferase, but differential effects on memory. However, basal forebrain cholinergic neurons send efferents to the amygdala and cortex. The present studies compared the effects of several excitotoxins on choline acetyltransferase levels in both of these stru...

fenugreek (trigonella foenum-graecum l.) has a long and respected history of medicinal uses in middle east and persian medicine. the hypocholesterolaemic and hypoglycaemic effects of fenugreek were attributed to its major steroidal sapogenin, diosgenin and its major alkaloid, trigonelline. the knowledge of diosgenin and trigonelline biosynthesis is derived from studies of cholesterol and nicoti...