Nicotinic acid, pellagra cure

After it had been established that pellagra was a nutritional deficiency disease, the next problem was to discover the missing nutrient. Additional dietary protein was shown to be beneficial, thus it was concluded that pellagra was because of a protein deficiency. This view, and later that it was more specifically from a deficiency of tryptophan, was held for some time. In 1938, Spies and coworkers showed that nicotinic acid would cure pellagra thereafter it was gradually accepted that it was a niacin deficiency disease. 

Pella r, Nia.cin 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). 

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. 

In 1937, Elvehjem and coworkers demonstrated that nicotinic acid cured canine "blacktongue." In the same year it was found to cure human pellagra, a terrible disease characterized by weakness, indigestion, and loss of appetite followed by dermatitis,... 

The history of niacin revolved around trying to find a way to prevent and cure pellegra, the late-stage deficiency disease caused by a niacin deficiency. Pellagra has been a serious nutritional disorder in the United States, mostly in the southeast. Two thousand deaths from pellagra were reported in 1941. This is ironic because nicotinic acid, later knovm as niacin, was first reported during the structure elucidation of the alkaloid nicotine. 

Nicotinic acid (niacin), when its use was introduced, cured hundreds of thousands of pellagra patients of their psychoses, as well as of the physical manifestations of their disease. For this purpose only small doses are required the recommended daily allowance (National Research Council) is 12 milligrams per day (for a 70-kilogram male). In 1939 Cleckley et al. reported the successful treatment of 19 patients, and... 

It was explained above how an antipellagra factor was included in the vitamin B2 complex. However, it was demonstrated that vitamin B2 (riboflavin), isolated from the vitamin B2 complex, did not show antipellagra activity in rats. As a result, the antipellagra factor separated from the vitamin B2 complex was called vitamin Bg [5]. Consequently, the factor that cures human pellagra is clearly different from this vitamin Bg. Thus, as the cure factors for black tongue disease of the dog, which resembles human pellagra, nicotinic acid and nicotinamide were isolated. 

Its previous discovery in yeast, as well as its presence in heart muscle extracts, emphasized the metaboUc significance of nicotinamide. The emergence of nicotinic acid or nicotinamide as a nutritional essential came from the demonstration by Elvehjem et al. that black tongue in dogs could be cured and prevented by its addition to the deficient diet. Simultaneously, FoutS et alJ, Smith et al. and Spies et al. reported the successful treatment of pellagra in human subjects. Its universal occurrence in living tissue and its fundamental role in cellular respiration are now well estabhshedi . 

HISTORY, Nicotinic acid was first discovered and named in 1867, when Huber, a German chemist, prepared it from the nicotine of tobacco. But for the next 70 years it remained idle on the chemist s shelves because no one thought of it, even remotely, as a cure for pellagra. In the meantime, thousands of people died from the disease. 

Deficiency of nicotinic acid may cause pellagra (a special form of dermatitis), diarrhea, and delirium. Interestingly enough, pellagra can be cured by the administration of tryptophan. This proves that the vitamin can be synthesized by the human organism. Pellagra appears endemically only where corn is the main constituent of food. Corn apparently contains a factor that restricts the biosynthesis of the vitamin furthermore, corn protein contains little tryptophan. 

NAD and NADP, which are important in redox reactions, are derivatives of niacin. Niacin is found in cereals in very small amounts, and is especially poor in maize. Pells ra is caused by niacin (B group) deficiency. It affects the skin, GI tract and the CNS. Remember the three Ds dermatitis, diarrhoea and dementia Pellagra can be cured by increasing the protein content of the diet, because nicotinic acid (niacin) can be formed in the body from tryptophan. Untreated deficiency causes death. 

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