Pyridine nucleotides in glucose metabolism and diabetes: a review

Abstract

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. This paper reviews current knowledge of the involvement of pyridine nucleotides and their precursors in glucose catabolism in the normal and diabetic state. Reference is also made to the following three current hypotheses for mechanisms underlying diabetic microangiopathy: Chronic glucose overutilization, caused by hyperglycemia, in tissues which lack insulin receptors and therefore are freely permeable to glucose. Enhancement of sorbitol pathway activity with an ensuing decrease in the ratio of NAD/NADH. 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. Copyright © 2000 John Wiley & Sons, Ltd.

Influence of gallic acid on oxidative stress-linked streptozotocin-induced pancreatic dysfunction in diabetic rats

“…LDH is a key metabolic enzyme that reversibly converts pyruvate and NADH, H + into lactate and NAD + . Diabetes is characterized by altered levels of NAD + and NAD + /NADH, H + ratios in metabolism [45]. Our results show that the activity of LDH is low in diabetic pancreas.…”

Effect of oral administration of diphenyl diselenide on antioxidant status, and activity of delta aminolevulinic acid dehydratase and isoforms of lactate dehydrogenase, in streptozotocin-induced diabetic rats

“…However, administration of DPDS significantly relieved this inhibition in the different isoforms of LDH studied. We speculate that increased levels of LDH in diabetic rats may result from the need to regulate the extent of cellular acidosis and respiration, which are markedly increased in diabetes (Yechoor et al 2002;Wahlberg et al 2000).…”

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Vitamin Deficiencies in Humans: Can Plant Science Help?

“…Niacin and nicotinamide serve as dietary precursors for the enzymatic cofactors NAD + and NADP + that are required in many redox reactions and are involved in fatty acid and carbohydrate metabolism (Wahlberg et al, 2000). NAD + is also a critical metabolite in cellular signaling reactions as it serves as a substrate for ADP-ribosyltransferases and ADPribosyl cyclases to generate ADP-ribosylated substrates and cyclic ADP-ribose, respectively (Lepiniec et al, 1995;DoucetChabeaud et al, 2001;Virá g and Szabó , 2002;Hassa et al, 2006;Pollak et al, 2007;Lamb et al, 2011).…”