Background: We hypothesized that the severity of dextran sodium sulfate (DSS)-induced colitis could differ between DSS preparations of the same molecular weight, and that this difference may be affected by the sulfur content. To test this, we used three DSS preparations of similar molecular weights but with different sulfur contents.
Methods: Three DSS preparations with molecular weights of 40,000 to 50,000 were tested: MP Biomedicals (MP Bio), USB (USB), and The Lab Depot (The Lab). Epithelial cell lines were used to assess the levels of poly (ADP-ribose) polymerase (PARP) in the presence of 2.0% DSS in vitro. Eight-week-old female C57/B6 mice were fed 2.0% DSS in water for 1 week, and then sacrificed to investigate the effects of the DSS preparations in vivo.
Results: In vitro experiments using CaCo-2 and CMT-93 cells revealed decreased PARP levels from all DSS preparations. Notably, the PARP level was significantly decreased in CaCo-2 cells treated with DSS from USB as compared to The Lab Mice treated with The Lab DSS had significantly decreased body weight losses on day 7 as compared to mice receiving DSS from MP Bio and USB. This result was supported by their DAI score, colon weight/length ratio, and histological scores.
Conclusion: The severity of colitis can differ between similar DSS preparations of the same molecular weight range. This difference in colitogenic properties may be affected by the total sulfur content of each DSS preparation.