女贞子对培养的黑素细胞酪氨酸酶活性和黑素合成的影响

目的 研究女贞子单体酪醇和齐墩果酸对人黑素细胞的增殖、酪氨酸酶活性及黑素合成的影响。方法 采用MTT法测定细胞增殖情况,多巴氧化法测定酪氨酸酶活性,氢氧化钠裂解法测定黑素含量,半定量RT-PCR检测药物对黑素细胞酪氨酸酶和酪氨酸酶相关蛋白-1 mRNA表达的影响。结果 加入酪醇72h后,各组黑素细胞的酪氨酸酶活性和合成黑素能力明显增强,且呈浓度依赖性;酪氨酸酶和酪氨酸酶相关蛋白-1 mRNA表达量分别比空白对照增加39.10%和99.26%;齐墩果酸也能明显激活酪氨酸酶(P<0.01),促进黑素合成(P<0.05),并使黑素细胞酪氨酸酶和酪氨酸酶相关蛋白-1mRNA表达量分别比加入无水乙醇的对照增加31.88%和17.73%。结论 酪醇和齐墩果酸可能通过上调酪氨酸酶和酪氨酸酶相关蛋白-1 mRNA的表达而增强正常人黑素细胞的黑素合成和酪氨酸酶活性:两者可能是女贞子中影响黑素细胞生物学活性的主要成分。

Effects of Fructus Ligustri Lucidi on the tyrosinase activity and melanogenesis of cultured human melanocytes

Objective To study the effects of tyrosol and oleanolic acid, two monomers of Fructus Ligustri Lucidi on the proliferation, tyrosinase activity and melanogenesis of cultured human melanocytes. Methods The cell proliferation was detected by MTT assay, the tyrosinase activity by dopa oxidase assay, the melanin content by NaOH - assay, and the mRNA level of tyrosinase ( TYR ) and tyrosinase related protein-1 (TRP-1) by RT-PCR. Results Incubation of tyrosol with cultured human melanocytes for 72 hours resulted in a significant stimulation of the tyrosinase activity and melanogenesis in a dose dependent manner. Compared with those in the cells without any treatment, the TYR and TRP-1 mRNA levels in the tyrosol -treated cells increased by 39.10% and 99.26%, respectively. Oleanolic acid also increased tyrosinase activity ( P < 0.01 ) and melanogenesis ( P < 0.05 ), and compared with those in the cells pretreated with absolute alcohol, the mRNA levels of TYR and TRP-1 in the cells pretreated with oleanolic acid increased by 31.88% and 17.73%, respectively. Conclusion The results suggest that tyrosol and oleanolic acid may stimulate tyrosinase activity and melanogenesis of cultured human melanocytes by upregulating the mRNA expression of TYR and TRP-1, and the two monomers may be the main active agents for the effects of Fructus Ligustri Lucidi on melanocytes.