Fig. 3.

Central GLP-1R activation decreases body weight and shifts combustion from carbohydrates towards fat in DIO mice. After 12 weeks of high-fat feeding, mice were treated for 5 days with i.c.v. exendin-4 (n = 10) or vehicle (control n = 6, pair-fed n = 9). Body weight gain (a) and food intake (b) were determined. Lean (crossed area) and fat (no cross) mass were measured (c). During the treatment period, mice were housed in metabolic cages. Fatty acid oxidation (d), carbohydrate oxidation (e), RER (f) and energy expenditure (g) were calculated from O₂ uptake and CO₂ excretion. (h) Magnitude of physical activity in arbitrary units. Values are mean ± SD. *p < 0.05, **p < 0.01 and ***p < 0.001 compared with control. ^† p < 0.05 and ^††† p < 0.001 compared with pair-fed control. White bars/continuous lines, control; black bars/dotted lines, exendin-4; grey bars/dashed lines, pair-fed controls. AU, arbitrary units; CH, carbohydrate; EE, energy expenditure; FA, fatty acid