Anti-inflammatory and anti-apoptosis activity of taraxasterol in ulcerative colitis in vitro and in vivo

Ulcerative colitis is closely associated with colorectal cancer, the long-standing chronic inflammation being the key etiology of ulcerative colitis. The aim of the present study was to identify the anti-inflammatory and anti-apoptosis activity of taraxasterol in ulcerative colitis. MTT assay was used to obtain the optimal concentrations of lipopolysaccharide (LPS) and taraxasterol for cell treatments in vitro. A mouse model of colitis was established via dextran sodium sulphate (DSS) administration. Levels of IL-6 and TNF-alpha were detected through ELISA. Flow cytometry and western blotting were used to detect apoptosis and related protein expression levels, respectively. Hematoxylin and eosin staining was performed to detect the pathological damage. The results from the MTT assay identified the optimal concentration of LPS and taraxasterol, and ELISA results demonstrated that taraxasterol treatment decreased the expression levels of IL-6 and TNF-alpha in vitro and in vivo, in a dose-dependent manner. Taraxasterol treatment inhibited apoptosis, and reduced the protein levels of p53, Bcl-2 associated X (BAX) and caspase-3. Finally, pathological damages were reduced in colonic tissues of mice treated with taraxasterol. Taken together, taraxasterol treatment markedly inhibited inflammation and apoptosis in ulcerative colitis. Therefore, taraxasterol may be a promising agent for decreasing the inflammatory response in ulcerative colitis and other inflammation-related diseases.