Fluid supplementation accelerates epithelial repair during chemical colitis

Area of Science:

• Animal Models
• Inflammatory Bowel Disease Research
• Gastroenterology

Background:

• The dextran sulfate sodium (DSS) model is widely used to study inflammatory bowel disease (IBD) in animals.
• This model causes significant pain and distress, necessitating welfare considerations.
• The potential of fluid supplementation as a welfare intervention requires investigation.

Purpose of the Study:

• To evaluate fluid supplementation as a welfare intervention in the DSS model of colitis.
• To assess the impact of fluid hydration on animal behavior, locomotive activity, and colitis progression.
• To investigate the effects of fluid supplementation on epithelial repair and inflammation.

Main Methods:

• C57Bl/6 female mice received 3% DSS in drinking water to induce acute colitis.
• One group received 1 mL intraperitoneal NaCl injections (fluid-supplemented), while controls did not.
• Behavioral tests (tail suspension, novel object recognition, open field) and histological/molecular analyses (inflammation, proliferation, differentiation markers) were performed.

Main Results:

• Fluid-supplemented mice showed reduced clinical signs of colitis without behavioral or locomotive changes.
• Accelerated epithelial repair was observed, with increased crypt proliferation and ERK1/2 activation.
• Fluid hydration led to more goblet cells, upregulated enterocyte differentiation markers, and reduced inflammation during recovery.

Conclusions:

• Fluid supplementation in DSS-treated mice alters colitis evolution by reducing clinical signs and enhancing epithelial repair.
• Fluid hydration does not appear to reduce stress or improve welfare in this model.
• Routine use of fluid supplementation in DSS-treated mice is not supported by these findings.