High-fat Diet Mouse Model for Metabolic Disorders

Six-week old, wild type (C57BL/6J) male mice were attained from the Animal Resources Centre (Australia). Mice were randomly allocated into seven groups, 10 each (n = 70). Group-1 was given low fat diet (LFD; healthy) and empty microcapsules, group-2 was given high fat diet (HFD; insulin-resistance) and empty microcapsules, group-3 was given HFD and metformin (200 mg/kg/day), group-4 was given HFD and low dose PB (80 mg/kg/day), group-5 was given HFD and high dose of PB (800 mg/kg/day), group-6 was given HFD and PBUDCA microcapsules (PB: 80 mg/kg/day and UDCA 70 mg/kg/day) and group-7 was given HFD and UDCA microcapsules (70 mg/kg/day). HFD consisted of AIN93M rodent chow enriched in 30% (w/w) lard, 0.5% (w/w) cholesterol and 15% (w/w) fructose (Specialty Feeds, Perth, Australia).
All mice were maintained on half-day dark cycle (22 °C) and with water and food ad libitum. At the end of 6-months experiment, mice were anaesthetized with isoflurane and euthanised by cardiac puncture followed by cervical dislocation. Blood was collected into EDTA tubes and stored on ice. Plasma was separated by short-speed centrifugation at 4 °C and stored at −80 °C. Tissues of different organs were removed at stored in 4% paraformaldehyde (PFA) at −80 °C. The animal experiments were approved by Curtin University Animal Ethics Committee and all experiments were performed according to the Australian Code of Practice for the care and use of animals for scientific purposes.