Antiproliferative and cell apoptosis-inducing activities of compounds from Buddleja davidii in Mgc-803 cells

Ten compounds were extracted and isolated from B. davidii, among which colchicine was identified in B. davidii for the first time. The inhibitory activities of these compounds were investigated in Mgc-803, Bcap-37 cells in vitro by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, and the results showed that luteolin and colchicine had potent inhibitory activities against the growth of Mgc-803 cells. Subsequent fluorescence staining and flow cytometry analysis indicated that these two compounds could induce apoptosis in Mgc-803 cells. The results also showed that the percentages of early apoptotic cells (Annexin V+/PI-, where PI is propidium iodide) and late apoptotic cells (Annexin V+/PI+) increased in a dose- and time-dependent manner. After 36 h of incubation with luteolin at 20 μM, the percentages of cells were approximately 15.4% in early apoptosis and 43.7% in late apoptosis; after 36 h of incubation with colchicine at 20 μM, the corresponding values were 7.7% and 35.2%, respectively.Colchicine and luteolin from B. davidii have potential applications as adjuvant therapies for treating human carcinoma cells. These compounds could also induce apoptosis in tumor cells.Buddleja belongs to the Loganiaceae family and has a pantropical distribution across South Asia, Africa, and America [1]. This genus comprises approximately 100 species of wood perennials and shrubs. The roots, leaves, and flowers of various species of Buddleja are used in folk medicine in several parts of the world [2]. Various bioactivities, including antimicrobial activity against Staphylococcus aureus, as well as antihepatotoxic, antirheumatic, antiprotozoal, and antifungal properties of isolated compounds from Buddleja have been reported [3-10]. The application of the poultice or lotion of a number of species of Buddleja to treat wounds has also been documented [11,12].Buddleja davidii is a perennial herbaceous plant widely distributed in the Chinese provinces of Yunnan,