DOM FIGURE 2 Comparison of AZD1656 and PF-04991532 (+)/(-) enantiomers with substrate challenge on gene expression in mouse hepatocytes.
A-D. Comparison of (+) and (-) enantiomers of PF-04991532 and AZD1656 on glucokinase activity assayed at 0.5mM glucose (A-B) and gene expression in hepatocytes in MEM with 5mM glucose (C-D). E. Pathway showing xylitol metabolism to fructose 6-P (F6P) and triose phosphates and sites of action of: AZD1656 and PF-04991532 (GKAs); S4048 (inhibitor of G6P hydrolysis); AOA (amino-oxyacetate, inhibitor of oxidation of cytoplasmic NADH). F-N. Hepatocytes from C57BL/6 mice were incubated for either 1h for metabolite analysis (F,G) or 4h for mRNA analysis (H-O) in MEM containing 5mM glucose (5G) and the additions indicated: 10μM AZD1656 (AZD); 10μM PF(+)04991532 (PF); xylitol (2mM, XY); AOA (0.1 mM) or with 25mM glucose without (25G) or with 0.4μM S4048 (25GS). Cell G6P and G3P are expressed as nmol/mg protein and cell ATP as % 5mM glucose control. mRNA levels are normalized to control incubations with 5mM glucose alone. Values are means ± SEM for n=4 (AOA, xylitol) or n=8 (all other conditions) hepatocyte preparations, * P < 0.05 relative to 5mM glucose alone.