Intestinal Lipid Metabolism Profiling

Small intestines were collected at 120 min after intragastric administration of triolein (10 μL/g body weight) to 12-h fasted mice, divided into three equal parts (proximal, middle, and distal) and processed as previously described (Cifarelli et al., 2017 (link)). Total triglyceride, cholesterol, and free fatty acids were determined by homogenizing 50 mg of tissue in 2 ml of chloroform:methanol (2:1 v/v). Samples were centrifuged at 12,000 rpm for 10 min at 4°C. An aliquote, 50 μl, was evaporated in a 1.5 ml microcentrifuge tube. Triglyceride and cholesterol were determined by adding 100 μL of reagent to dried lipid extracts followed by incubation for 30 min at room temperature. Level of triglyceride and cholesterol in plasma was determined using Fisher Scientific kits (Fisher Scientific, PA, United States). Non-esterified fatty acid levels in plasma were determined using Wako kit (Wako Chemicals, Richmond, VA, United States) according to the manufacturer’s protocol.