Cirsilineol, a natural flavone compound, selectively inhibits IFN-γ/STAT1/T-bet signaling in intestinal CD4+ T cells. Cirsilineol has potent immunosuppressive and anti-tumor properties. Cirsilineol significantly ameliorates trinitro-benzene sulfonic acid (TNBS)-induced T-cell-mediated experimental colitis in mice[1].
Cirsilineol (0.1-10 μM; 96 hours) inhibits single mixed lymphocyte reaction and Concanava A-induced T-cell proliferation in a dose-dependent manner. Cirsilineol (10 μM) does not affect T lymphocyte’s viability. The inhibition of cirsilineol (10 μM) on T-cell proliferation is not due to a cytotoxic activity[1]. Cirsilineol (1-10 μM; pretreatment for 3 hours) completely inhibits IFN-γ-induced Tyr701 phosphorylation of STAT1 and JAK2 activation[1].
cirsilineol (3, 10, and 30 mg/kg) significantly ameliorates TNBS-induced Th1-mediated colitis through inhibiting IFN-γ/STAT1/T-bet signaling in CD4+ T cells.
[1]. Yang Sun, et al. Novel immunomodulatory properties of cirsilineol through selective inhibition of IFN-gamma signaling in a murine model of inflammatory bowel disease. Biochem Pharmacol. 2010 Jan 15;79(2):229-38.