NAD+-Consuming Enzymes in the Regulation of Lung Immune Responses

Nicotinamide adenine dinucleotide (NAD+) plays a role as a coenzyme in numerous oxidation-reduction reactions and mediates not only energy metabolism and mitochondrial functions, but also calcium homeostasis, aging, and cell death. Moreover, extensive evidence attests to the great importance of the non-redox functions of NAD+ via NAD+consuming enzymes. Indeed, ADP-ribose transferases, cADP-ribose synthases and sirtuins emerge as NAD+ dependent enzymes with potent regulatory function in many physiological and pathophysiological processes. They have been shown to be involved in several neurological and cardiovascular disorders as well as in cancer and inflammation. In this review we will summarize the current knowledge about function of NAD+-consuming enzymes in the regulation of the immune system with particular emphasis on lung inflammatory disorders.