Pyridine nucleotides in glucose metabolism and diabetes: a review.

"Nicotinamide adenine dinucleotide (NAD) and its derivatives NADH, NADP and NADPH have regulatory functions in the generation of triose phosphates and pyruvate from glucose. In many studies of the influence of the diabetic state on relationships between pyridine nucleotide and glucose metabolism, the focus has been on the sorbitol pathway.

Less attention has been paid to other aspects of the role of pyridine nucleotides in pyruvate formation from glucose, in particular the effects of the NAD precursors nicotinamide and nicotinic acid on glucose metabolism.

Reference is also made to the following three current hypotheses for mechanisms underlying diabetic microangiopathy:

1. Chronic glucose overutilization, caused by hyperglycemia, in tissues which lack insulin receptors and therefore are freely permeable to glucose.
2. Enhancement of sorbitol pathway activity with an ensuing decrease in the ratio of NAD/NADH.
3. Enhanced utilization of both glucose and pyridine nucleotides in formation of triose phosphates and pyruvate.

Therapy with NAD precursors like nicotinamide might have corrective effects on these proposed biochemical aberrations, thereby retarding progression of microangiopathy.

About the Authors

Wahlberg G, Adamson U, Svensson J. (2000). Pyridine nucleotides in glucose metabolism and diabetes: a review. Diabetes Metab Res Rev 2000 Jan-Feb;16(1):33-42. Research Unit, Serafen Health Centre, Karolinska Institutet at Danderyd Hospital, Stockholm, Sweden.