Beyond Pellagra-Research Models and Strategies Addressing the Enduring Clinical Relevance of NAD Deficiency in Aging and Disease

Research into the functions of nicotinamide adenine dinucleotide (NAD) has intensified in recent years due to the insight that abnormally low levels of NAD are involved in many human pathologies including metabolic disorders, neurodegeneration, reproductive dysfunction, cancer, and aging. Consequently, the development and validation of novel NAD-boosting strategies has been of central interest, along with the development of models that accurately represent the complexity of human NAD dynamics and deficiency levels. In this review, we discuss pioneering research and show how modern researchers have long since moved past believing that pellagra is the overt and most dramatic clinical presentation of NAD deficiency. The current research is centered on common human health conditions associated with moderate, but clinically relevant, NAD deficiency. In vitro and in vivo research models that have been developed specifically to study NAD deficiency are reviewed here, along with emerging strategies to increase the intracellular NAD concentrations.

Pellagra and the nutritional neuropathies: a neuropathological review

It is now well recognized that many of the syndromes previously described as pellagra, such as nutritional retrobulbar neuropathy, the ataxic, and burning feet syndromes, may occur as isolated manifestations of nutritional deficiency. The term “pellagra,” as it is often used, is no more than a generic title embracing a wide variety of nutritional disorders. The clinical status of the individual deficiency syndromes has been elucidated of late years in America (Spies et al., 1939; Harris, 1941), and with particular regard to the neurological disorders, in groups of prisoners of war in the Far East (Denny Brown, 1947) and Middle East (Spillane, 1947). The majority of the pathological studies of pellagra were completed in the era before advancing biochemical knowledge provided the impetus to further these clinical studies, and this is reflected in the great diversity of neuropathological changes described as “pellagrous.” The extensive literature contains many excellent studies of cases dying from malnutrition, and it now seems possible to attempt a correlation between the pathological findings and the more recently described individual syndromes. A review, therefore, of the neuropathological changes encountered in “pellagra” might be not untimely.

Leprosy with pellagroid features (a case report)

A case of leprosy with pellagroid features is presented. Diagnosis of leprosy was confirmed by bacteriological and histopathological examination. A therapeutic trial with nicotinic acid did not result in any improvement. Occurrence of scaling in leprosy is discussed.