Characterisation of acute murine dextran sodium sulphate colitis: Cytokineprofile and dose dependency

Background/Aims: in our experience with the acute murine dextran sodium sul phate (DSS) model of experimental colitis, we noted both interstrain and in teranimal variations in daily water consumption. One might critically quest ion whether observed differences in injuries are just a dose dependency phe nomenon reflecting variations in DSS intake. To clarify this important topi c, we performed a dose and concentration dependency study of DSS in Balb/c mice. We also determined Th1 and Th2 cytokine levels to compare the cytokin e profile to that from inflammatory bowel disease (IBD). Methods: In four g roups (14 animals each group) different concentrations of DSS (0, 2.5, 5 an d 7.5%) were given for 7 days ad libitum. Mucosal injury of the entire colo n was histologically assessed and graded. Cytokine levels were determined b y competitive quantitative RT-PCR. Results: A linear increase in the crypt damage score was noted with increasing concentrations (0, 4.9 +/- 0.7, 11.9 +/- 0.5 and 18.9 +/- 1.3, respectively), but the total dose of DSS intake did not correlate with mucosal damage. Progressive upregulation in the tran scripts for Th1 cytokines (IL-12, IFN-gamma, IL-1, INF-alpha) was observed with increasing dosage of DSS. Interestingly, an increase in IL-10, but not IL-4 mRNA transcripts was also noted. Discussion: Acute DSS-induced mucosa l injury is dependent on the administered DSS water concentration but not o n the consumed DSS dose. The cytokine profile is a classic Th1 response and is similar to that of various inflammatory conditions in the colon. Conclu sions: Minor variations in fluid consumption do not affect the severity of DSS-induced injury in mice. The acute murine DSS colitis model is useful fo r studying the pathophysiological aspects of colonic inflammatory diseases as IBD and for evaluating new potential therapeutic agents Copyright (C) 20 00 S. Karger AG, Basel.