Transgenic Mouse Models for Adipose Research

The PPARγ-tTA, TRE-Cre, Sox2-Cre, floxed ERα, TRE-H2B-GFP, R26R-RFP and R26R-lacZ mice were maintained as described and used to generate controls, mutants and lineage reporter mouse lines^{29 (link)–31 (link)}. AdipoTrak mice are defined as PPARγ-tTA; TRE-Cre; TRE-H2B-GFP. AT-ERαKO mutants are homozygous for ERα^f/f allele, while controls are homozygous for ERα^+/+ or lack TRE-Cre regardless of ERα alleles. The mice were housed in a temperature-controlled environment using a 12:12 light/dark cycle, and chow and water were provided ad libitum. The mice were fed either normal chow (4% fat, Harlan-Teklad, Madison, WI) or HFD (60%, Harlan Teklad). Fat content was measured using a minispec mq10 NMR Analyzer (Bruker). For glucose and insulin tolerance tests, 1.25 mg glucose or 1.5 mU Humalog (Lilly)/g mouse weight was injected intraperitoneally (IP) after a 5-h fast; blood glucose levels were measured at the indicated intervals^{31 (link),57 (link)}. BrdU was IP injected (100 mg kg⁻¹ body mass) or provided in the drinking water (0.5 mg ml⁻¹ in 1% sucrose). Sera insulin was measured by using an ELISA kit in the metabolic core. Veterinary care was provided by Division of Comparative Medicine. Animals were maintained under UT Southwestern Medical Center Animal Care and Use Committee guidelines according to current NIH guidelines under animal protocol 2010–0015.