LC/MS/MS Profiling of Tissue Oxysterols and its Application in Dextran Sodium Sulphate Induced Mouse Colitis Models.

We have developed a workflow to extract, separate, and semi-quantify bioactive oxysterols from mouse colon tissues and fecal matters using solid- and liquid-phase extractions, enzymatic and chemical modifications, and stable-isotope dilution LC/MS/MS. The method was applied to a dextran sodium sulphate (DSS)-induced mouse colitis model, which revealed that one particular dihydroxycholesterol (diOHC), 7α,25-diOHC, was significantly elevated in both colon tissue and fecal matters of mice with colitis compared to that in naïve mice. The extent of 7α,25-diOHC elevation was positively correlated with colitis severity.