Effect of norcantharidin on the proliferation, apoptosis, and cell cycle of human mesangial cells.

Aims: Norcantharidin (NCTD) regulates immune system function and reduces proteinuria. We sought to investigate the effect of NCTD on proliferation, apoptosis and cell cycle of cultured human mesangial cells (HMC) in vitro. Methods: HMC cells were divided into a normal control group, and various concentrations of NCTD group (2.5, 5, 10, 20, or 40 mu g/mL). Cell proliferation was determined by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, apoptosis was detected by Annexin V/propidium iodide (PI) assays, and morphological analysis was performed by Hoechest 33258 staining. Finally, cell cycle was analyzed by flow cytometry. Results: NCTD dose and time dependently inhibits HMC proliferation significantly (p<. 05). Apoptosis dose and time dependently increased after NCTD treatment. Cell-cycle analysis revealed that the number of cells in the G2 phase increased significantly, whereas the fraction of cells in the S phase decreased, especially 24 h after 5 mu g/ml NCTD treatment. Conclusion: NCTD inhibits HMC cell proliferation, induces apoptosis, and affects the cell cycle.