2.3. Animals, diets and experimental design
The study was carried out in accordance with the ‘Guide for the Care and Use of Laboratory Animals’ as promulgated by the National Institute of Health, and the protocols approved by the Ethic Committee of Laboratory Animals of the University of Granada (Spain) (Ref. No. 28/03/2016/030). Male C57BL/6J mice (5 weeks old) obtained from Charles River Laboratories (Barcelona, Spain) were housed in a temperature and humidity-controlled facility (22 ± 1°C, 55 ± 10% relative humidity) with a 12-hour light/dark cycle and provided with a free access to tap water. Mice were fed with either a standard chow diet (13% calories from fat, 20% calories from protein and 67% calories from carbohydrate) (Global diet 2014; Harlan Laboratories, Barcelona, Spain) or a HFD in which 60% of its caloric content was derived from fat (Purified diet 230 HF; Scientific Animal Food & Engineering, Augy, France). Mice were randomly assigned to different groups (n =10): control (control diet), obese (HFD) and obese treated (L. fermentum ). Control group received the standard chow while obese groups were fed the HFD. HFD-L. fermentum mice were administered the probiotic L. fermentum at 5x108 CFUs in 100 μl/mouse/day and control mice received PBS. The treatment was followed for 11 weeks, controlling regularly animal body weight, food and water intake.