db/db Mice Exhibit Features of Human Type 2 Diabetes That Are Not Present in Weight-Matched C57BL/6J Mice Fed a Western Diet

Figure 7

Derangements in the skeletal muscle and liver fat oxidation occur in db/db mice, while diet-induced obesity only negatively impacts skeletal muscle fat oxidation. Using [1-¹⁴C] palmitate (100 μM), substrate switching was assessed by measuring complete (CO₂) and incomplete (acid soluble metabolite (ASM)) fat oxidation ± varying doses of pyruvate as a competing substrate. Assays were run using homogenates from mixed gastrocnemius (MG) skeletal muscle (a, b, e, f) and liver (c, d, g, h) from diet-induced (control diet versus Western diet for 20 weeks; a–d) and a genetically obese model (db/+ versus db/db mice aged 14 weeks; e–h) of obesity. per group; means ± SEM. versus control; versus control; versus control; versus control by two-way repeated measures ANOVA with Bonferroni post hoc test for multiple comparisons.