Dextran Sodium Sulfate-Induced Colitis Model in Mice

To induce acute experimental colitis, mice were administered 1.5-3.0% (w/v) dextran sodium sulfate (DSS, molecular weight, 36-50 kDa; MP Biomedicals, UK) in their drinking water ad libitum for 7 days followed by 7 days normal water. Parthenolide (PTL) (10 mg/kg) suspended in saline was administered by intraperitoneal (i.p.) injection in PTL+DSS group mice from day 0 to day 14 until the end of experiments. Mice in DSS group underwent i.p. injection of normal saline as a negative control. To avoid abdominal infection caused by i.p. injection, the procedures were strictly performed under sterile conditions. In all colitis models, mice were checked daily for morbidity and body weight was recorded. Each mouse was scored daily for pathological features, including stool consistency, presence of blood stool, and body weight loss. Individual scores were combined to generate the Disease Activity Index (DAI) which was calculated daily for each mouse. The maximum score was 12 based on assigning a 0-4 scoring system for following parameters (Supplementary Table S1).