[Experimental study on artesunate inducing apoptosis of hypertrophic scar fibroblasts]

To study the effect and mechanism of the apoptosis of hypertrophic scar fibroblasts (HSF) induced by artesunate (Art).

HSFs were isolated and cultured from human earlobe scars by the tissue adherence method. The 3th to 5th generation cells were harvested and divided into two groups. HSF was cultured with normal medium in control group and with medium containing 60, 120 and 240 mg/L (5 ml) Art in experimental group. Apoptosis and cell cycle were identified by light microscopy, electronmicroscopy and flow cytometry. Then, HSF was cultured with normal medium in control group and with medium containing 30, 60 and 120 mg/L Art in experimental group. The changes of intracellular calcium concentration were observed.

The primary HSF was fusiform in shape and adherent. The vimentin positive expression was analyzed by immunocytochemistry. Art could induce apoptosis of HSF in the range of 60-240 mg/L under inverted microscope. The effect was dose- and time-dependent. Clumping of nuclear chromatin showed margination in the experimental group. And the disaggregation of the nucleolus were observed under electronmicroscopy. There were significant differences in the proportion of HSF apoptosis and HSF at G0-G1, S, G2-M stages between the two groups (P < 0.05). Apoptotic peak was shown in experimental group by flow cytometry. The peak became more evident as Art concentration increased. The intracellular calcium concentration elevated markedly in HSF with 30-120 mg/L Art treatment for 24 hours, showing significant differences between the two groups (P < 0.05).

The Art facilitates HSF cells apoptosis in vitro by the change of cell cycle. It is suggested that intracellular calcium variation may be one of the mechanisms of HSF apoptosis induced by Art.