Drug screening identifies pyrrolidinedithiocarbamate ammonium ameliorating DSS-induced mouse ulcerative colitis via suppressing Th17 differentiation

T helper 17 (Th17) cells play crucial roles in various autoimmune diseases, including ulcerative colitis (UC), which is characterized by widespread inflammation in the mucosa of the colon and rectum. To identify small-molecule compounds capable of inhibiting CD4⁺ T cell differentiation into Th17 cells, we established a screening system. Through drug screening, we found that pyrrolidinedithiocarbamate ammonium (PDTC) effectively inhibits Th17 differentiation. In a dextran sulfate sodium (DSS)-induced UC mouse model, administration of PDTC significantly ameliorated colitis. PDTC treatment decreased the production of proinflammatory mediators and inhibited the proportion of Th17 cells in colitis-afflicted mice by suppressing NF-κB activation. These findings showed that PDTC can alleviate colitis by inhibiting NF-κB activation. The therapeutic effects of PDTC observed in a mouse model of UC provided a rationale for its application in clinical settings.