Selective β3-adrenoceptor agonist reduces energy intake and elevates GDF15 levels in lean and diet-induced obese mice

β3-Adrenoceptors (β3ARs) are expressed in the adipose tissue, the brain, and the bladder. In rodents, selective β3AR agonists have been shown to reduce normal chow intake through central and peripheral mechanisms. However, the impact of β3AR agonists on nutritional balance, as well as the relative contribution of each organ system to this effect, remains elusive. In this study, we aimed to determine whether the peripheral effect of β3AR agonists on food intake is nutrient-specific or energy in general using food choice experiments that allow for independent analysis of energy and nutrients. Mice were presented with two different diet options (normal diet [ND] vs. high-sucrose diet [HSD], high-fat diet [HFD], or high-protein diet [HPD]), and the effects of the β3AR agonist CL316,243 on the intake of these diets were examined. Treatment with CL316,243 reduced total energy intake, primarily through decreased consumption of HSD, HFD, and HPD. Accordingly, CL316,243 reduced food intake in a non-nutrient-specific manner, resulting in decreased caloric intake. In addition, CL316,243 increased plasma levels of fibroblast growth factor 21 (FGF21) and growth differentiation factor 15 (GDF15). In the ND vs. HSD food choice test, CL316,243 reduced HSD intake, even in liver-specific Fgf21 knockout mice. Furthermore, CL316,243 reduced food intake in mice with diet-induced obesity. These findings suggest that the CL316,243-mediated reduction in HSD intake occurs independently of liver-derived FGF21. Moreover, elevated plasma GDF15 levels were positively associated with reduced food intake induced by CL316,243.