In chow diet, body weight and growth of KO mice was comparable to WT littermates in both sexes (Fig. 2a and Supplementary Fig. 2a). Similarly, there was no observable difference in fed and fasted glucose levels and serum insulin and leptin concentrations (Supplementary Fig. 2b–i). However, unexpectedly, the KO mice exhibited modestly but significantly improved glucose and insulin sensitivity with no difference in insulin levels when the mice were challenged with glucose and insulin (Fig. 2b–d and Supplementary Fig. 2j–k). These results show that deletion of FoxO1 in DA neurons enhanced glucose/insulin sensitivity without affecting the insulin secretion.
