HIF1A and colitis: In an animal colitis model, the systemic administration of Hif1α inhibitor, PX-478, attenuates the protective effects of exogenous H2S and epithelial regeneration in dinitrobenzene sulfonic acid-treated rat colitis model (41), whereas Hif1α activation by DMOG (42, 43), FG-4497 (44) or CG-598 (45) results in enhancement of epithelial barrier functions against animal colitis models.