青蒿琥酯诱导瘢痕成纤维细胞凋亡的实验研究

目的探讨青蒿琥酯（artesunate，Art）诱导皮肤瘢痕成纤维细胞凋亡的作用及机制。方法取自愿捐献的人耳垂增生性瘢痕，采用组织块贴壁法进行细胞培养。经免疫组织化学染色鉴定后，取第3～5代成纤维细胞，采用含60、120和240mg／LArt培养液各5ml培养作为实验组，仅加入等量的培养液作为对照组。于倒置显微镜及透射电镜观察，采用流式细胞仪观察细胞凋亡及细胞周期。另取第3～5代成纤维细胞，实验组采用30、60和120mg／LArt培养液，对照组仅加入等量的培养液，观察细胞内钙离子的变化。结果原代成纤维细胞呈典型的梭形贴壁生长，免疫组织化学鉴定细胞波形蛋白呈阳性表达；倒置显微镜下观察Art在60～240mg／L浓度范围内抑制成纤维细胞生长且呈剂量及时间依赖性，细胞出现凋亡征象；透射电镜观察，各实验组出现染色质浓缩，沿着核膜排列，甚至核碎裂现象。细胞周期分析显示各实验组与对照组比较，凋亡细胞比例、处于G0～G1、S、G2～M期细胞数差异均有统计学意义（P〈0．05），实验组均出现典型的凋亡峰，且随药物浓度增加，峰值越大。Art在30～120mg／L作用成纤维细胞24h可引起细胞内钙离子浓度持续增加，与对照组比较，差异有统计学意义（P〈0．05）。结论Art通过作用于成纤维细胞周期诱导细胞凋亡，细胞内钙离子浓度升高可能是其诱导成纤维细胞凋亡的机制之一。

EXPERIMENTAL STUDY ON ARTESUNATE INDUCING APOPTOSIS OF HYPERTROPHIC SCAR FIBROBLASTS

OBJECTIVE: To study the effect and mechanism of the apoptosis of hypertrophic scar fibroblasts (HSF) induced by artesunate (Art). METHODS: 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. RESULTS: 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). CONCLUSION: 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.