雷公藤红素下调HL-60细胞P-Akt与Cyclin D1蛋白表达及其诱导细胞凋亡的效应

本研究探讨雷公藤红素诱导HL-60细胞凋亡及其可能的作用机制。以不同浓度雷公藤红素(0.25-8.0μmol/L)分别作用于HL-60细胞24-72小时,采用MTT法检测细胞增殖活性;TUNEL荧光染色、流式细胞术观察雷公藤红素对HL-60细胞凋亡及周期的影响;Western blot、RT-PCR法分别检测雷公藤红素对HL-60细胞内Akt(P-Akt)及其下游分子Cyclin D1的蛋白、基因的表达水平。结果表明,雷公藤红素能明显抑制HL-60细胞增殖,具有浓度依赖和时间依赖性。此外,雷公藤红素以浓度依赖性方式诱导HL-60细胞凋亡,并伴随明显的凋亡细胞形态学改变。雷公藤红素的凋亡诱导可能与其诱导HL-60细胞周期阻滞于G0/G1期有关。雷公藤红素对P-Akt及CyclinD1蛋白及基因表达水平均有不同程度的抑制作用,该抑制作用呈明显的量效和时效关系。结论:雷公藤红素明显抑制HL-60细胞的增殖,并诱导其凋亡,其抗白血病效应可能与其下调P-Akt和Cyclin D1蛋白表达有关。

Celastrol Down-Regulates Expression of P-Akt and Cyclin D1 in HL-60 Cells and Induces Apoptosis

The aim of this study was to investigate the effect of Celastrol on induction of HL-60 cell apoptosis and its possible mechanism. The proliferative activity of HL-60 cells treated with 0.25 - 8.0 μmol/L of Celastrnl for 24 - 72 hours was assayed by MTT method, the effects of Celastrol on apoptosis and cell cycle of HL-60 were detected by TUNEL staining and flow cytometry with Annexin V-FITC/PI double labeling, the expression of pAkt and cyclin D1 at protein and gene level in HL-60 cells treated with Celastrol were measured by Western blot and RT-PCR. The results showed that the Celastrol could obviously inhibit the proliferation of HL-60 cells in concentration-and time-dependent manners, the IC50 value of Celastrol for 24 hours was 6.21 ± 0. 242 μmol/L. The Celastrol concentration-dependently induced the apoptosis of HL-60 cells, accompanying with morphological changes of apoptotic cells, which may be related with arrest of cells in G0/G1 phase. The Celastrol suppressed the expression of pAkt and Cyclin D1 in HL-60 cells to a varying degree which showed obvious concentration-and time-dependent manners. It is concluded that the Celastrol inhibits the proliferation and induced the apoptosis of HL-60 cells. Its mechanism may be related with downregulation of p-Act and cyclin D1 expressions.