Sources and implications of NADH/NAD(+) redox imbalance in diabetes and its complications

• Published in: Diabetes, metabolic syndrome and obesity Vol. 9; no. Issue 1; pp. 145 - 153
• Main Authors: Wu, Jinzi, Jin, Zhen, Zheng, Hong, Yan, Liang-Jun
• Format: Journal Article
• Language: English
• Published: New Zealand Taylor & Francis Ltd 01.01.2016; Dove Medical Press
• Subjects: Apoptosis; Chinese medicine; Dehydrogenases; Diabetes; Enzymes; Fatty acids; Glucose; Hyperglycemia; Insulin resistance; Liver diseases; Metabolism; NADH/NAD+ redox imbalance; Oxidation; oxidative damage; Oxidative stress; Pathogenesis; poly ADP ribosylation; polyol pathway; Proteins; Review; Rodents; sirtuins; Smooth muscle; polyol pathway; mitochondria; sirtuins; poly ADP ribosylation; reactive oxygen species; complex I; oxidative damage; oxidative stress
• ISSN: 1178-7007; 1178-7007
• DOI: 10.2147/dmso.s106087

NAD(+) is a fundamental molecule in metabolism and redox signaling. In diabetes and its complications, the balance between NADH and NAD(+) can be severely perturbed. On one hand, NADH is overproduced due to influx of hyperglycemia to the glycolytic and Krebs cycle pathways and activation of the polyol pathway. On the other hand, NAD(+) can be diminished or depleted by overactivation of poly ADP ribose polymerase that uses NAD(+) as its substrate. Moreover, sirtuins, another class of enzymes that also use NAD(+) as their substrate for catalyzing protein deacetylation reactions, can also affect cellular content of NAD(+). Impairment of NAD(+) regeneration enzymes such as lactate dehydrogenase in erythrocytes and complex I in mitochondria can also contribute to NADH accumulation and NAD(+) deficiency. The consequence of NADH/NAD(+) redox imbalance is initially reductive stress that eventually leads to oxidative stress and oxidative damage to macromolecules, including DNA, lipids, and proteins. Accordingly, redox imbalance-triggered oxidative damage has been thought to be a major factor contributing to the development of diabetes and its complications. Future studies on restoring NADH/NAD(+) redox balance could provide further insights into design of novel antidiabetic strategies.