HDAC1 and inflammatory bowel disease: Correspondingly, the expression levels of HDAC2 and HDAC3 proteins were approximately 1.7 (for HDAC2)- and 1.5 (for HDAC3)-fold higher in IBD model mice compared with normal ones (Figure 3F,G), and no significant change was observed in the expression levels of HDAC1 proteins in IBD model mice (Figure 3E).