Niacin pellagra

The water-soluble vitamins comprise the B complex and vitamin C and function as enzyme cofactors. Fofic acid acts as a carrier of one-carbon units. Deficiency of a single vitamin of the B complex is rare, since poor diets are most often associated with multiple deficiency states. Nevertheless, specific syndromes are characteristic of deficiencies of individual vitamins, eg, beriberi (thiamin) cheilosis, glossitis, seborrhea (riboflavin) pellagra (niacin) peripheral neuritis (pyridoxine) megaloblastic anemia, methyhnalonic aciduria, and pernicious anemia (vitamin Bjj) and megaloblastic anemia (folic acid). Vitamin C deficiency leads to scurvy. 

Hartnup disorder exhibits symptoms similar to pellagra (niacin deficiency), characterized by three of the "four D s" diarrhea, dermatitis (a red, scaly rash), dementia (intermittent ataxia), and death... 

Pellagra, Niacin Deficiency. It was 220 years after the first description of pellagra that nicotinic acid was discovered to be the cure for black tongue in dogs (14), a condition suggested by a veterinarian in North Carolina to be similar to human pellagra (15). 

Early 1900s Treatment of histamine shock, pellagra (niacin deficiency) and rickets (vitamin D deficiency) Electrocardiography and cardiac catheterization... 

DEFICIENCY Pellagra. Niacin may be produced from tryptophan (1-8). Niacin deficiency therefore is most likely in persons with low intake of both niacin and tryptophan. People who eat mainly com may develop niacin deficiency as com is low in tryptophan. In pellagra, the patient develops the 3 D s Diarrhea, Dermatitis, and Dementia. Diagnostic testing is difficult and may best be done by seeing improvement with niacin ingestion. 

The reasons for niacin deficiency in individuals nourished on a corn or maize diet are still not clear. Corn is low in niacin and tryptophan, but it is also possible that the niacin in corn forms a chemical complex that cannot be used therefore, the lime treatment of the corn used in Central American diets may be important in preventing pellagra. Niacin is not the active molecule in the body. The importance of niacin, as we have previously seen, stems from its role in NAD and NADP synthesis, and the deficiency can be expected to lead to reduced NAD and NADP concentrations in liver and blood serum. However, the exact significance of this reduction is not clear. Up to now, it has been impossible to establish a direct correlation between the growth rate and the amount of NAD in the liver. 

Pellagra is a disease caused by a deficiency of niacm (C6FI5NO2) in the diet Niacin can be synthesized in the laboratory by the side chain oxidation of 3 methylpyndine with chromic acid or potassium permanganate Suggest a reasonable structure for niacin... 

NADP can be converted to nicotinic acid adenine dinucleotide phosphate (NAADP), which has distinct functions in the regulation of intracellular calcium stores. The studies of these new roles of NAD(P) in metabolism are in their early stages, but they might soon help to better understand and explain the symptoms of niacin deficiency ( pellagra) [1]. 

Niacin is recommended to alleviate pellagra, a disease caused by a deficiency of this vitamin. 

Niacin Nicotinic acid, nicotinamide Coenzyme in oxidation and reduction reactions, functional part of NAD and NADP Pellagra—photosensitive dermatitis, depressive psychosis... 

Niacin was discovered as a nutrient during studies of pellagra. It is not strictly a vitamin since it can be synthesized in the body from the essential amino acid tryptophan. Two compounds, nicotinic acid and nicotinamide, have the biologic activity of niacin its metabolic function is as the nicotinamide ring of the coenzymes NAD and NADP in oxidation-reduction reactions (Figure 45-11). About 60 mg of tryptophan is equivalent to 1 mg of dietary niacin. The niacin content of foods is expressed as mg niacin equivalents = mg preformed niacin + 1/60 X mg tryptophan. Because most of the niacin in cereals is biologically unavailable, this is discounted. 

Pellagra Can Occur as a Result of Disease Despite an Adequate Intake of Tryptophan Niacin... 

A number of genetic diseases that result in defects of tryptophan metabolism are associated with the development of pellagra despite an apparently adequate intake of both tryptophan and niacin. Hartnup disease is a rare genetic condition in which there is a defect of the membrane transport mechanism for tryptophan, resulting in large losses due to intestinal malabsorption and failure of the renal resorption mechanism. In carcinoid syndrome there is metastasis of a primary liver tumor of enterochromaffin cells which synthesize 5-hydroxy-tryptamine. Overproduction of 5-hydroxytryptamine may account for as much as 60% of the body s tryptophan metabolism, causing pellagra because of the diversion away from NAD synthesis. 

Niacin (Bj) Dehydrogenases Many Pellagra diarrhea, dementia, dermatitis, and, if not treated, death... 

A deficiency of niacin in the diet results in the disease known as pellagra, characterized by the four D s diarrhea, dermatitis, dementia, and death. In the early years of the twentieth century in the United States, pellagra was common among poor tenant farmers and mill workers in the rural South. The diet there at that time was rich in com that contained little niacin and little available tryptophan from which to synthesize it. 

Niacin, which refers to nicotinic acid and nicotinamide, is the metabolic precursor to three nicotinamide coenzymes. These are essential for the activity of a large number of enzymes catalyzing redox reactions. Pellagra is a niacin deficiency disease. 

Oxidation of nicotine with chromic acid led to the isolation of pyridine-3-carboxylic acid, which was given the trivial name nicotinic acid. We now find that nicotinic acid derivatives, especially nicotinamide, are biochemically important. Nicotinic acid (niacin) is termed vitamin B3, though nicotinamide is also included under the umbrella term vitamin B3 and is the preferred material for dietary supplements. It is common practice to enrich many foodstuffs, including bread, flour, corn, and rice products. Deficiency in nicotinamide leads to pellagra, which manifests itself in diarrhoea, dermatitis, and dementia. 

Nicotinate and nicotinamide, together referred to as niacin, are required for biosynthesis of the coenzymes nicotinamide adenine dinucleotide (NAD"") and nicotinamide adenine dinucleotide phosphate (NADP" ). These both serve in energy and nutrient metabolism as carriers of hydride ions (see pp. 32, 104). The animal organism is able to convert tryptophan into nicotinate, but only with a poor yield. Vitamin deficiency therefore only occurs when nicotinate, nicotinamide, and tryptophan are all simultaneously are lacking in the diet. It manifests in the form of skin damage (pellagra), digestive disturbances, and depression. 

It is used for pellagra (avitaminosis PP), atherosclerosis, liver disease, stomach and duodenum ulcers, and prolonged, nonhealing wounds and ulcers. Synonyms of this drag are niconacid, pemivit, enzycol, niacin, and others. 

Deficiency - Pellagra is a state of niacin deficiency characterized by dermatitis, diarrhea, and dementia (manifestations of mucous membranes, Gl system, and CNS). In severe cases, confusion, delusions, disorientation, and hallucinations may occur. 

Pyridoxine is indicated in vitamin B deficiency, for the treatment of some pyridoxine responsive anemia s and for isoniazid-induced neuropathy. It may relieve symptoms of pellagra when niacin fails. Long-term administration of large doses may produce neurotoxicity manifesting itself in progressive peripheral sensory neuropathy. 

Niacin was initially called pellagra preventing factor. 

Deficiency symptoms In niacin deficiency, pellagra develops. The main... 

Pellagra is often characterized by mental abnormalities such as anxiety, irritability, and depression. The classic symptoms of pellagra are known as the 4 Ds -dementia, diarrhea, dermatitis, and death. Inflammation of mucosal surfaces, weakness, anorexia, and other gastrointestinal disturbances are also seen. Niacin (300 to 500 mg per day) is the definitive therapy. 

Nicotine forms a number of metabolites in the body, mainly in the liver. Approximate 75% of nicotine is oxidized to cotinine, which is the primary nicotine metabolite. Cotinine can be measured in the blood, urine, and saliva and this is used as a measure of nicotine exposure in tobacco users and in those exposed to secondhand smoke. The oxidation of nicotine also produces nicotinic acid. Nicotinic acid is vitamin B3 and has the common name niacin. Niacin deficiency results in a disease called pellagra, which is found in certain malnourished populations. Pellagras symptoms include dermatitis, diarrhea, sensitivity to light, and dementia. 

The classical niacin deficiency disease is pellagra, which is characterized by symptoms including diarrhoea, dermatitis, dementia and eventually death. High-protein diets are rarely deficient in niacin since, in addition to the preformed vitamin, such diets supply sufficient tryptophan to meet dietary requirements. Large doses of niacin can cause the dilation of capillaries, resulting in a painful tingling sensation. 

Dietary Deficiency of Niacin, the Vitamin Form of NAD and NADP, Causes Pellagra... 

FIGURE 13-17 Structures of niacin (nicotinic acid) and its derivative nicotinamide. The biosynthetic precursor of these compounds is tryptophan. In the laboratory, nicotinic acid was first produced by oxidation of the natural product nicotine—thus the name. Both nicotinic acid and nicotinamide cure pellagra, but nicotine (from cigarettes or elsewhere) has no curative activity. 

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