Aziz Moammir Hassan, Afaq Farrukh, Ahmad Nihal
Department of Dermatology, University of Wisconsin, 1300 University Avenue, Madison, WI 53706, USA.
Photochem Photobiol. 2005 Jan-Feb;81(1):25-31. doi: 10.1562/2004-08-13-RA-274.
Nonmelanoma skin cancer is the most frequently diagnosed malignancy in the United States, and multiple exposures to solar ultraviolet (UV) radiation (particularly its UV-B component, 290-320 nm), is its major cause. 'Chemoprevention' by naturally occurring agents is being appreciated as a newer dimension in the management of neoplasia including skin cancer. We recently demonstrated that resveratrol (trans-3, 5, 4-trihydroxystilbene), an antioxidant found in grapes, red wines and a variety of nuts and berries, imparts protection from acute UV-B-mediated cutaneous damages in SKH-1 hairless mice. Understanding the mechanism of resveratrol-mediated protection of UV responses is important. We earlier demonstrated that resveratrol imparts chemopreventive effects against multiple UV-exposure-mediated modulations in (1) cki-cyclin-cdk network, and (2) mitogen activated protein kinase (MAPK)-pathway. This study was conducted to assess the involvement of inhibitor of apoptosis protein family Survivin during resveratrol-mediated protection from multiple exposures of UV-B (180 mJ/cm(2); on alternate days; for a total of seven exposures) radiations in the SKH-1 hairless mouse skin. Our data demonstrated that topical pre-treatment of resveratrol (10 micromol in 200 microl acetone/mouse) resulted in significant inhibition of UV-B exposure-mediated increases in (1) cellular proliferations (Ki-67 immunostaining), (2) protein levels of epidermal cyclooxygenase-2 and ornithine decarboxylase, established markers of tumor promotion, (3) protein and messenger RNA levels of Survivin, and (4) phosphorylation of survivin in the skin of SKH-1 hairless mouse. Resveratrol pretreatment also resulted in (1) reversal of UV-B-mediated decrease of Smac/DIABLO, and (2) enhancement of UV-B-mediated induction of apoptosis, in mouse skin. Taken together, our study suggested that resveratrol imparts chemopreventive effects against UV-B exposure-mediated damages in SKH-1 hairless mouse skin via inhibiting Survivin and the associated events.
非黑色素瘤皮肤癌是美国最常被诊断出的恶性肿瘤,多次暴露于太阳紫外线(UV)辐射(尤其是其UV-B成分,290 - 320纳米)是其主要病因。天然物质的“化学预防”正被视为肿瘤包括皮肤癌治疗中的一个新领域。我们最近证明,白藜芦醇(反式-3,5,4-三羟基芪),一种存在于葡萄、红酒以及各种坚果和浆果中的抗氧化剂,能保护SKH-1无毛小鼠免受急性UV-B介导的皮肤损伤。了解白藜芦醇介导的对紫外线反应的保护机制很重要。我们 earlier证明白藜芦醇对多种紫外线暴露介导的(1)细胞周期蛋白激酶抑制因子-细胞周期蛋白-细胞周期蛋白依赖性激酶网络和(2)丝裂原活化蛋白激酶(MAPK)途径的调节具有化学预防作用。本研究旨在评估凋亡抑制蛋白家族Survivin在白藜芦醇介导的保护SKH-1无毛小鼠皮肤免受多次UV-B(180 mJ/cm²;隔天一次;共七次暴露)辐射中的作用。我们的数据表明,局部预处理白藜芦醇(每只小鼠200微升丙酮中含10微摩尔)可显著抑制UV-B暴露介导的以下各项增加:(1)细胞增殖(Ki-67免疫染色)、(2)表皮环氧化酶-2和鸟氨酸脱羧酶的蛋白水平,这两种是已确定的肿瘤促进标志物、(3)Survivin的蛋白和信使RNA水平以及(4)SKH-1无毛小鼠皮肤中Survivin的磷酸化。白藜芦醇预处理还导致(1)UV-B介导的Smac/DIABLO减少的逆转以及(2)小鼠皮肤中UV-B介导的凋亡诱导增强。综上所述,我们的研究表明白藜芦醇通过抑制Survivin及相关事件,对UV-B暴露介导的SKH-1无毛小鼠皮肤损伤具有化学预防作用。