Abstract:

Objective To study the effect of artesunate on inducing mitochondrial apoptosis of myofibro⁃ blasts，the key cells of fibrosis，and to explore the effect on the expression of BCL ⁃2 family. Methods Human pulmonary myofibroblasts model was constructed. CCK⁃8，flow cytometry and JC⁃1 were used to detect the changes of cell activity，apoptosis initiation and apoptosis status of the myofibroblasts treated with artesunate. RT⁃qPCR and western blot were used to detect α⁃SMA and BCL⁃2 family gene expression. Results Human pulmonary myofibro⁃ blasts expressing α⁃SMA were successfully constructed by adding 10 ng/mL TGF⁃β to fibroblasts for 48 h. In artesu⁃ nate treating group，the cell viability of myofibroblasts was significantly decreased（P < 0.001），but the percentage of apoptotic cells（Annexin V+）was significantly increased（P < 0.001）. The red fluorescence intensity decreased significantly in the artesunate group［from（17.58 ± 1.08）to（1.28 ± 0.35）］，especially at 24 ~ 36 h. The red and green fluorescence intensity（JC ⁃1 signal）did not change significantly in the control group. Compared with the control group，the mRNA expression of anti ⁃apoptotic BCL ⁃2 in the artesunate group was significantly decreased （P < 0.001），but the mRNA expression of pro⁃apoptotic BIM（P < 0.01）and PUMA，BMF and HRK（P < 0.05） were increased. The mRNA expression of BAX，BAK，BAD and NOXA did not change significantly. Conclusion Artesunate regulates the pro⁃apoptotic/anti⁃apoptotic balance of mitochondrial BCL⁃2 family by down⁃regulating the expression of gene BCL ⁃2，up ⁃ regulating the expressions of genes BIM，PUMA，BMF and HRK，and triggering the initiation of mitochondrial apoptosis，thereby inducing the apoptosis of human pulmonary myofibroblasts.

Key words:

artesunate, myofibroblasts, the BCL?2 family, mitochondrial apoptosis