Malondialdehyde-acetaldehyde (MAA) adducted proteins bind to scavenger receptor A in airway epithelial cells
Malondialdehyde-acetaldehyde (MAA) adducted proteins bind to scavenger receptor A in airway epithelial cells
复制标题
DOI：
10.1016/j.alcohol.2014.02.005
复制
发表时间：
2014-08-01
期刊：
影响因子：
2.3
通讯作者：
Wyatt, Todd A.
中科院分区：
文献类型：
--
作者：
Berger, John P.;Simet, Samantha M.;Wyatt, Todd A.
同时暴露在香烟烟雾和乙醇中会产生丙二醛和乙醛，这会导致乙醛加合物蛋白质的形成。我们先前已经证明，支气管上皮细胞暴露于丙二醛-乙醛(MAA)加成的蛋白会增加蛋白激酶C(PKC)的活性和促炎细胞因子的释放。清道夫受体A(SEA)的特定配体岩藻糖胶阻断了这一作用。我们推测MAA加合物蛋白通过SEA与支气管上皮细胞结合。将人支气管上皮细胞(BEAS-2B)暴露于MAA加成蛋白(牛血清白蛋白[BSA-MAA]或表面活性蛋白D[SPD-MAA])和SEA，用共聚焦显微镜、荧光激活细胞分选(FACS)和免疫沉淀等方法检测SEA。气液界面培养的分化小鼠气管上皮细胞(MTEC)检测MAA刺激的PKC活性和角质形成细胞源性趋化因子(KC)的释放。MAA作用3~7min后，特异性细胞表膜染料与上调的SEA共定位，20min后消退。同样，MAA加成的蛋白在3-7分钟内共定位到SEA，随后MAA内化10分钟。这些结果得到了FACS分析的证实，并显示SEA的平均荧光在3分钟后减少。此外，免疫沉淀的SRA样品经MAA处理3min后，Western印迹检测到MAA加合物蛋白的含量增加。MAA可刺激野生型小鼠PRC epsilon介导的KC释放，但不能刺激SEA基因敲除小鼠的KC释放。这些数据表明，在MAA加成蛋白刺激呼吸道上皮细胞释放依赖于PKC的炎性细胞因子之前，肺中的醛加合物蛋白迅速与SEA结合并内化该受体。(C)2014 Elsevier Inc.保留所有权利。
Co-exposure to cigarette smoke and ethanol generates malondialdehyde and acetaldehyde, which can subsequently lead to the formation of aldehyde-adducted proteins. We have previously shown that exposure of bronchial epithelial cells to malondialdehyde-acetaldehyde (MAA) adducted protein increases protein kinase C (PKC) activity and proinflammatory cytokine release. A specific ligand to scavenger receptor A (SEA), fucoidan, blocks this effect. We hypothesized that MAA-adducted protein binds to bronchial epithelial cells via SEA. Human bronchial epithelial cells (BEAS-2B) were exposed to MAA-adducted protein (either bovine serum albumin [BSA-MAA] or surfactant protein D [SPD-MAA]) and SEA examined using confocal microscopy, fluorescent activated cell sorting (FACS), and immunoprecipitation. Differentiated mouse tracheal epithelial cells (MTEC) cultured by air-liquid interface were assayed for MAA-stimulated PKC activity and keratinocyte-derived chemokine (KC) release. Specific cell surface membrane dye co-localized with upregulated SEA after exposure to MAA for 3-7 min and subsided by 20 min. Likewise, MAA-adducted protein co-localized to SEA from 3 to 7 min with a subsequent internalization of MAA by 10 min. These results were confirmed using FACS analysis and revealed a reduced mean fluorescence of SEA after 3 min. Furthermore, increased amounts of MAA-adducted protein could be detected by Western blot in immunoprecipitated SRA samples after 3 min treatment with MAA. MAA stimulated PRC epsilon-mediated KC release in wild type, but not SEA knockout mice. These data demonstrate that aldehyde-adducted proteins in the lungs rapidly bind to SEA and internalize this receptor prior to the MAA-adducted protein stimulation of PKC-dependent inflammatory cytokine release in airway epithelium. (C) 2014 Elsevier Inc. All rights reserved.