惠坤,简强,薛柯,朱东宁,安庆,李承新

[摘要]目的：探讨乙酰水杨酸（acetylsalicylic acidASA）在UVB诱导黑素细胞树突形态相关分子Rac1和RhoA表达中的作用。方法：培养正常人表皮黑素细胞系PIG1细胞，将细胞以一定密度接种于平皿中，并随机分为三组，对照组、100mJ UVB照射组及UVB照射后ASA处理组。ASA处理24h后采用RT-PCR 检测Rac1和RhoA mRNA表达的变化及Western blot检测蛋白表达的变化。结果：PIG1细胞经100mJ UVB照射后与对照组相比，促进树突形成的Rac1表达较对照组明显增高，而抑制树突形成的RhoA表达下调；ASA处理可反转UVB照射对Rac1和RhoA的作用， Rac1表达较UVB照射组明显降低，而RhoA表达增高。结论：一定剂量UVB照射后，黑素细胞Rac1表达增高，RhoA表达下调；ASA可以抑制一定剂量UVB照射诱导的黑素细胞树突形态相关分子的改变。

[关键词]黑素细胞；UVB照射；ASA；树突；Rac1；RhoA

[中图分类号]Q813.1[文献标识码]A[文章编号]1008-6455（2012）04-0587-03

Effect of ASA on the expression of the dendrites regulating factors Rac1 and RhoA in melanocytes induced by UVB irradiation

HUI Kun,JIAN Qiang,XUE Ke,ZHU Dong-ning,AN Qing,LI Cheng-xin

(Institute of Dermatology,Xijing Hospital,the Fourth Military Medical University,Xi'an 710032,Shaanxi,China)

Abstract:ObjectiveTo investigate the effect of acetylsalicylic acid (ASA )on the expression of the dendrites regulating factors Rac1 and RhoA in melanocytes induced by UVB Irradiation.MethodsMelanocytes cultured in plates were divided into 3 groups, control group, 100mJ UVB irradiation group and UVB irradiation plus ASA treatment group, respectively.The mRNA expression of Rac1 and RhoA was analysed with real time RT-PCR, and protein expression was assayed by western blotting.ResultsCompared with control group, UVB irradiation enhanced the protein and mRNA expression of Rac1,while decreased the expression of RhoA. However, ASA treatment could inhibit the influence of UVB irradiation on the Rac1 and RhoA. The protein and mRNA expression of Rac1was decreased obviously and expression of RhoA was enhanced after treatment with ASA.ConclusionsUVB irradiation can increase the expression of Rac1 and decrease the expression of RhoA in melanocytes and ASA can suppress these change induced by UVB irradiation.

Key words:melanocyte;UVB irradiation;ASA;Rac1;RhoA;dendrites

色素沉着的过程十分复杂，其中黑素的合成与转运是最为重要的两个环节。UVB照射不仅能够增加黑素合成，本课题组先前的实验证明其还可以明显促进黑素小体的转移及转运。目前有研究表明，乙酰水杨酸（acetyl salicylic acid，ASA）具有淡化色斑的作用，但ASA是否能够影响UVB诱导的黑素小体的转运尚不清楚。本实验检测ASA对UVB诱导黑素细胞树突形态相关分子的影响，探讨ASA在黑素小体转运中的作用。

1材料和方法

1.1材料：永生化的人表皮黑素细胞系PIG1来自美国艾利诺斯州Loyola医学中心，254培养基、HMGS添加剂（Cascade Biologics公司），标准胎牛血清、Trizol核酸提取液（GibcoBRL），ASA、胰蛋白酶（Sigma公司），RT-PCR试剂盒（Takara公司），BCA蛋白定量检测试剂盒（Pierce公司），兔抗人Rac1单抗、鼠抗人RhoA单抗（abcam公司），山羊抗鼠二抗（HRP）（北京中山生物技术有限公司），紫外线光疗仪（上海希格玛公司），辐照度以UVB辐照度监示器标定，UVB剂量=UVB辐照度×时间(s)，均为单次照射。……