Study on Toxic Effects and Mechanism of Osthole on L02 Cells

OBJECTIVE To investigate the toxic effect of osthole (Ost) on L02 cells and explore its mechanism, which could provide an experimental evidence for the safe and rational application of fructus cnidii and its preparation. METHODS Different concentrations of Ost were applied to L02 cells, MTT assay was used to detect cell activity;the release rate of lactate dehydrogenase (LDH) was analyzed using LDH kits;Hoechst 33342 staining was used to detect cell nucleus morphology;Annexin V/PI staining was used to detect apoptosis;Western blot was utilized to detect the expression of Bcl-2, Bax, pro-caspase-3, cleaved-caspase-3(p17) and p-Histon H3(Ser10). RESULTS The activity of L02 cells decreased under the action of Ost, while the release rate of LDH increased and appeared to be concentration dependent. The cell nucleus treated by Ost were shrunken and fragmented under Hoechst 33342 fluorescence staining. The results of double staining of Annexin V/PI showed that the apoptosis rate increased with the increase of Ost concentration. compared with the control group, after Ost (50, 100, 200 μmol·L^-1) treatment for 24 h, the expression levels of Bcl-2, pro-caspase-3 and p-Histon H3(Ser10) decreased, and the expression levels of Bax and cleaved-caspase-3 increased. CONCLUSION Ost has toxic effects on L02 cells, which appeares a time and concentration dependent manner, as a result it will promote apoptosis and inhibit cell proliferation.