Systemic GADD45β deletion affects metabolic regulation under conditions of heightened lipid metabolism Systemic GADD45β deletion affects metabolic regulation under conditions of heightened lipid metabolism A–GMale GADD45β+/+ (WT; n = 6) or GADD45β−/− (KO; n = 4) mice were fed ad libitum (fed) or fasted for 24 h (fasted) and subsequently refed for 24 h. O2 consumption rate (A), CO2 production rate (B) and respiratory exchange ratio (C) were measured by indirect calorimetry. In a distinct cohort, male GADD45β+/+ (WT; n = 5) or GADD45β−/− (KO; n = 8) were fed ad libitum (fed) or fasted for 24 h (fasted). Serum non‐esterified fatty acids (D) and ketone bodies (E) as well as serum (F) and liver (G) triglycerides (TG) were measured.H–JSerum TG (H), NEFA (I) and blood glucose (BG, J) concentrations during an oral lipid tolerance test in overnight fasted GADD45β+/+ (WT; n = 5) or GADD45β−/− (KO; n = 5) mice.K–NBlood glucose excursion during and intraperitoneal insulin tolerance test (K) as well as fasting blood glucose (L), serum insulin (M) and HOMA‐IR (N) in GADD45β+/+ (WT; n = 6) or GADD45β−/− (KO, n = 9) chronically fed a normal‐ (NFD) or high (HFD)‐fat diet.Data information: Data are mean ± SEM. Effect of genotype, *P < 0.05, **P < 0.01, ***P < 0.001. Effect of nutritional state: #P < 0.05, ##P < 0.01, ###P < 0.001. The statistical test used and respective P‐value outputs can be found in Appendix Table S1. Jessica Fuhrmeister et al. EMBO Mol Med. 2016;8:654-669 © as stated in the article, figure or figure legend