SIRT1 and colitis: SIRT1 deletion might be useful in the improvement of disease conditions in colitis via induction of Foxp3 + T-regulatory cells, which are important for intestinal homeostasis.724,725 The loss of SIRT1 in thymic–derived natural Tregs did not affect rescue from autoimmune colitis, although it promoted Foxp3+ development from conventional T cell formation and attenuated autoimmune colitis.724 These conclusions suggest that the deleterious role of SIRT1 in immune-related diseases might be related to different T cell sources.