蛋白酶体抑制对黑素细胞酪氨酸酶表达及输出的影响  

Impact on tyrosinase expression and export from endoplasmic reticulum by inhibition of 26S proteasome

作　　者：许文[1] 林福全[1] 刘继锋[1] 傅丽芳[1] 洪为松[1] 周妙妮[1] 许爱娥[1] 关翠萍[1] 

机构地区：[1]杭州市第三人民医院皮肤科,310009

出　　处：《中华医学杂志》2013年第2期123-127,共5页National Medical Journal of China

基　　金：国家自然科学基金（30800563、81071294）;浙江省自然科学基金（Y2101132、Z2100973）;杭州市科技发展计划（20092133W04）

摘　　要：目的明确蛋白酶体抑制对黑素细胞酪氨酸酶表达及输出的影响。方法Western印迹检测8例白癜风患者和4名健康对照皮肤组织26S蛋白酶体水平。蛋白酶体抑制剂（1actacystin）处理黑素细胞后，四甲基偶氮唑盐（MTr）法测定黑素细胞活性，检测蛋白酶体活性，电镜观察黑素细胞内质网形态，激光共聚焦观察酪氨酸酶与内质网标志蛋白的共定位表达，Western印迹分析26S蛋白酶体和酪氨酸酶表达水平。结果白癜风患者皮损部位26S蛋白酶体表达水平（1．05±0．40）显著低于正常表皮部位（1．82±0．88）和健康对照（1．88±0．16）（P〈0．05），但后二者间差异无统计学意义（P〉0．05）。与未处理组相比，10μmol／Llactacystin处理12h后对黑素细胞开始有显著抑制作用（细胞活性吸光度值：0．999±0．110比1．372±0．127，P〈0．05），蛋白酶体活性显著低于未处理组（0．234±0．019比1，P〈0．01）。lactacystin处理组内质网相对膨胀值显著高于未处理细胞（1．91±0．17比1．17±0．11，P〈0．01）。lactacystin处理组酪氨酸酶与内质网标志蛋白共定位于内质网，而未处理组酪氨酸酶能有效输出于内质网。与未处理组相比，lactacystin处理组酪氨酸酶表达水平显著下降（146±10比269±8，P〈0．01），且酪氨酸酶活性也显著下降（0．159±0．017比0．221±0．019，P〈0．01）。结论白癜风患者皮损处26S蛋白酶体水平显著下降，蛋白酶体抑制引起黑素细胞内质网膨胀，影响酪氨酸酶有效输出于内质网及表达。Objective To determine the impact on tyrosinase expression and export from endoplasmic reticulum by inhibition of 26S proteasome. Methods Western blot was used to detect 26S proteasome from 8 vitiligo patients and 4 healthy controls. Melanocytes were incubated with proteasome inhibitor （lactacystin） and further detected as follows： ceil survival by MTT assay, proteasome activity with fluorescence, uhrastructure observation with electron microscope, co-localization of tyrosinase and calreticulin （endoplasmic reticulum marker） by confocal laser scanning microscopy and 26S proteasome and tyrosinase with Western blot. Results The 26S proteasome expression level from lesions of vitiligo （ 1.05 ± 0.40） was significantly lower than the donor sites （ 1.82 ±0. 88） and the healthy controls （ 1.88 ±0. 16） （P 〈 0. 05）. But no significant difference existed between the latter two groups （ P 〉 0. 05 ）. Compared to the untreated group, a 12-h incubation of 10 Ixmol/L lactacystin showed inhibitory effects on melanocytes （0. 999±0. 110 vs 1. 372 ± 0. 127, P 〈 0. 05 ） and significantly decreased proteasome activity （0. 234 ± 0. 019 vs 1, P 〈 0. 01 ）. Expansion rate of endoplasmic reticulum in the laetacystin group （ 1.91 ± 0. 17 ） was significantly higher than that of the untreated cells （ 1.17 ± 0. 11 ） （ P 〈 0. 05 ）. More tyrosinase co- localized with calreticulin in endoplasmic reticulum in lactaeystin-treated cells was observed than that of the untreated group. Compared with the untreated group, significantly decreased levels of tyrosinase （ 146 ± 10 vs 269 ±8, P 〈 0. 0l ） and tyrosinase activity （ 0. 159 ± 0. 017 vs 0. 221 ± 0. 019, P 〈 0. 0l ） were shown inthe lactacystin group （P 〈 0. 05 ）. Conclusions Significantly decrease of 26S proteasome is found in lesions of vitiligo patients. Inhibition of 26S proteasome may lead to expansion of endoplasmic reticulum of melanocytes, impact export of tyrosinase from melanocyte endoplasmic reticu

关 键 词：白癜风 黑素细胞 一元酚单氧酶 蛋白酶体 

分 类 号：R758.41[医药卫生—皮肤病学与性病学]