中药单体对黑色素瘤细胞增殖的抑制作用及对酪氨酸酶活性的影响

摘要

目的:研究五种中药单体对人恶性黑色素瘤细胞A375体外增殖的影响和对细胞内酪氨酸酶活性的作用.方法:将具有美白功效的五种中药单体(熊果苷、丹参素、芦荟大黄素、姜黄素和丹参酮ⅡA)分别与A375细胞作用.MTT比色法观察这五种中药单体对A375细胞体外增殖的影响;多巴速率氧化法研究这些中药单体对A375细胞内酪氨酸酶活性的作用.结果:五种中药单体对A375细胞增殖均有抑制作用,且呈浓度依赖性(P<0.05).熊果苷、丹参素、芦荟大黄素、姜黄素均可抑制A375细胞内酪氨酸酶的活性;且作用48 h后,高浓度的熊果苷和丹参素仍可显著抑制酪氨酸酶活性(P<0.05),而芦荟大黄素及姜黄素虽对酪氨酸酶活性仍有抑制作用,但无统计学差异.丹参酮ⅡA在不同浓度下均未检测到对酪氨酸酶活性的抑制作用.结论:五种中药单体对A375细胞增殖均有抑制作用,且呈浓度依赖性;一定浓度的熊果苷和丹参素对A375细胞增殖抑制的同时亦可显著抑制细胞内酪氨酸酶活性;而芦荟大黄素、姜黄素、丹参酮ⅡA对细胞内酪氨酸酶活性均未见明显抑制作用.我们推测对酪氨酸酶活性的抑制作用可能是具有美白功效的中药单体熊果苷和丹参素抑制A375细胞增殖的作用机理之一,而芦荟大黄素、姜黄素及丹参酮ⅡA可能是通过其他机制来抑制细胞增殖.%Objective:To investigate the effects of five Chinese herbal medicine monomers on the proliferation and tyrosinase activity of the human malignant melanoma cell line A375.Methods:Melanoma cell A375 was treated with the Chinese medicine monomers(arbutin,Danshensu,aloe-emodin,curcumin and tanshinone ⅡA).Cell prolifera-tion was examined by MTT assay.Tyrosinase activity was detected by measuring the oxidation rate of levo-dopa(L-DOPA).Results:All five Chinese medicine monomers showed dose-dependent inhibition of A375 cell proliferation at various concentrations(P<0.05).Arbutin,Danshensu,aloe-emodin and curcumin inhibited tyrosinase activity. After 48 h,high concentrations of both arbutin and Danshensu could continue to inhibit tyrosinase activity significantly (P<0.05),while tanshinoneⅡA failed to inhibit tyrosinase activity at a variety of concentrations.Conclusion:Chi-nese herbal medicine monomers(arbutin,Danshensu,aloe-emodin,curcumin and tanshinone ⅡA)inhibited A375 cell proliferation in a dose-dependent manner,while only arbutin and Danshensu inhibit tyrosinase activity signifi-cantly.We speculated that the inhibition effect of tyrosinase activity could be a conceivable mechanism for the anti-melanoma function of arbutin and Danshensu,while aloe-emodin,curcumin and tanshinone ⅡA may inhibit A375 cell proliferation through other mechanisms.