PARL and colitis: In vivo experiment, RT-PCR, IHC and western blotting showed that compared with wild-type mice, the mRNA and protein expression level of PARL, PINK1 and Parkin in intestinal mucosa of hsf2−/− DSS colitis mice were significantly changed: the level of PARL was increased, while the level of PINK1 and Parkin were decreased (Figure 5).