Dextran sodium sulphate

To induce colon carcinoma, mice were injected intraperitoneally with 10 mg/kg body weight of AOM (Azoxymethane-Sigma) dissolved in saline [24 (link)]. Seven days after AOM injection, 2% DSS (Dextran sodium sulphate -Sigma) was given in drinking water for the next seven days, followed by normal water until the 21^st week. At the 21^st week, mice were sacrificed after 1.5 h of BrdU injection (100 mg/kg body weight). For macroscopic examinations, colons were opened longitudinally and fixed overnight in buffered 4% para-formaldehyde. For histological examination, colons were fixed overnight in buffered 4% para-formaldehyde, rolled, embedded in paraffin and sectioned (4 μm thickness). Sections were mounted on positively charged slides (Fisher Scientific) and were stained either with H&E or with anti-BrdU antibodies. Primary antibody was detected with superpicture^™ kit (87-8963- Invitrogen). For apoptosis, TUNEL assay was performed as per the manufacturer’s instructions (Promega). For western blot and real time PCR, proximal colon was collected in PBS, snap frozen in liquid nitrogen and stored at −80°C.

Dextran Sodium Sulphate (DSS, 4%; Sigma-Aldrich) and Paraquat (5mM; Sigma-Aldrich) were used for in vivo stress experiments. Young adult flies were starved for 4hours followed by feeding them with appropriate stressor in 5% sucrose-saturated filter paper. Intestines were dissected 24 or 48 hours after treatment start as indicated in figure legends.
Sodium Arsenite treatment was performed as describe previously [39 (link)]. In short, guts from seven-day-old animals were dissected in Schneider’s media and incubated for 1 hour in Schneider’s media with or without 10mM Sodium Arsenite. Following treatment, guts were washed and processed for regular immunohistochemistry.

Colitis was induced by dextran sodium sulphate (DSS; Sigma-Aldrich). Twelve week old female WT mice and Nur77^-/- mice (10 per group) were exposed to 1.5% of DSS in their drinking water every day for 7 days. The mice were weighed every morning. Mice were sacrificed at day 8.