calculated according to the manufacturer’s guidelines (Pheno- Master Software, TSE Systems, Bad Homburg, Germany) and normalized to LBM. The respiratory exchange ratio (RER) was estimated by calculating the ratio of VCO2/VO2. Statistical Analysis Data are expressed as means 6 Standard Errors of the Mean (SEM). Area under the curves (AUCs) were calculated using the algorithm provided in the PRISM software package (GraphPad, San Diego, CA). Significance was tested using analysis of variance (ANOVA) with Newman-Keuls hoc test (P,0.05) or Student’s t test (P,0.05) as indicated in figure legends. Supporting Information Figure S1 Het GIP Tg mice didn’t exhibit increased energy expenditure. After 11–12 weeks of feeding, WT and Het GIP Tg mice (16–17 weeks old, n = 4,5/group) were placed in individual cages, and physical activity was assessed during the light and dark cycle. A and B. Energy expenditure in LF (A)- and HF (B) diet-fed Het GIP Tg and WT littermates. C and D. Oxygen consumption in LF (C)- and HF (D) diet-fed Het GIP Tg and WT littermates. E and F. Respiratory exchange rate in LF (E)- and HF (F) diet-fed Het GIP Tg and WT littermates. All data represent the mean 6 S.E.M. and significance was tested using ANOVA with a Newman-Keuls post hoc test, where ** represents p,0.05 vs indicated group; N.S. represents not significant. (TIF) References 1. Doyle M, Egan J (2003) Pharmacological agents that directly modulate insulin secretion. Pharmacological Reviews 55: 105–131. 2. Stumvoll M, Goldstein B, van Haeften T (2005) Type 2 diabetes: principles of pathogenesis and therapy. Lancet 365: 1333–1346. 3. Padwal R, Majumda S, Johnson J, Varney J, McAlister F (2005) A systematic review of drug therapy to delay or prevent type 2 diabetes. Diabetes Care 28: 736– 744. 4. Kahn SE, Haffner SM, Heise MA, Herman WH, Holman RR, et al. (2006) Glycemic durability of rosiglitazone, metformin, or glyburide monotherapy. 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(2008) Targeted ablation of glucose-dependent insulinotropic polypeptide-producing cells in transgenic mice reduces obesity and insulin resistance induced by a high fat diet. J Biol Chem. 283: 18365–76. 27. Fulurija A, Lutz TA, Sladko K, Osto M, Wielinga PY, et al. (2008) Vaccination against GIP for the treatment of obesity. PLoS ONE 3: e3163. 28. Hinke SA, Pauly RP, Ehses J, Kerridge P, Demuth HU, et al. (2000) Role of glucose in chronic desensitization of isolated rat islets and mouse insulinoma (betaTC-3) cells to glucose-dependent insulinotropic polypeptide. J Endocrinol. 165: 281–91. PLoS ONE | www.plosone.org 13 July 2012 | Volume 7 | Issue 7 | e40156