Zonarol reduces the apoptotic activity of the colonic epithelium in mice with DSS-induced UC.

A) A small but substantial number of apoptotic epithelial cells (TUNEL staining) in crypts were identified in each group of mice 15 days after the administration of DSS (n = 6 mice per group). The number of TUNEL+ (green-stained in nuclei) large intestinal epithelial cells in the zonarol-treated mice was significantly larger than that in the normal control mice on day 15 post-DSS administration, but was smaller than that in the DSS positive control mice. B) Double-IF staining confirmed that these TUNEL+ apoptotic cells (green-stained in nuclei) were CK20+ colonic epithelial cells in the crypts (red-stained in cytoplasm). Scale bars = 100 µm (medium-power view); and 25 µm (high-power view). The values are the means ± SE. *P