Diterpenoids and triterpenoids from the roots of Tripterygium regelii and their inhibitory effects on colorectal cancer cells

A total of 22 terpenoids including one new triterpenoid ( 1 ), two new diterpenoids ( 2 and 3 ), and 19 known compounds ( 4 – 22 ) were isolated from the roots of Tripterygium regelii . Their structures were identified using NMR and HRESIMS techniques. Antiproliferative activity screening assays revealed that the new compound 2 , along with several known compounds, exhibits potential anti-colorectal cancer efficacy. Further investigations employing flow cytometry, immunofluorescence staining and electron microscopy demonstrated that compound 2 induces the generation of reactive oxygen species (ROS). This, in turn, promotes lipid peroxidation and mitochondrial damage, ultimately enhancing ferroptosis in colorectal cancer cells. These findings underscore the value of compound 2 as a potential candidate for anti-tumor drug development.