Figure 2.

Redox state changes induced by the polyol pathway hyperactivity under high glucose conditions. Nicotinomide adenoside dinucleotide phosphate (NADPH) consumption during the first step catalyzed by aldose reductase (AR) suppresses the activities of glutathione reductase (GR) and nitric oxide synthase (NOS), which leads to the reduction in glutathione (GSH) and NO, respectively. NADH upregulation during the second step catalyzed by SDH increases the activities of NADH oxidase and PKCβ. GAP: glyceraldehyde 3-phosphate, DHAP: dihydroxyacetone phosphate. Red and blue arrows indicate increases and decreases in the amount or activity of molecules, respectively.