Figure 2

Colitis is associated with downregulation of colonic Sirt6 expression in mice and humans. For (A) the mouse colitis model, wild-type C57BL/6J mice (male, 8–10 wks old) were given drinking water containing 3.5% DSS for up to 7 d. Colonic tissues were collected at the indicated time points (n = 5 per time point). For (B) human samples, mucosal biopsies from the sigmoid colons of health individuals (n = 17) and UC patients (n = 15) were obtained through diagnostic colonoscopy procedures. Tissue samples were processed for assessment of expression of Sirt6 protein with (A) Western blot or (B) mRNA, as described in Materials and Methods. (A) Sirt6 protein levels in colon during development of DSS-induced colitis in mice. Upper panel: autoradiograph of a representative immunoblot. Lower panel: densitometric analysis of the immunoblot data (normalized to β-actin). (B) Relative expression of SIRT6 mRNA in the sigmoid colon biopsies of healthy individuals and UC patients. Results are expressed as mean ± SEM. *, P < 0.05 versus 0 d.