Identification in human atherosclerotic lesions of GA-pyridine, a novel structure derived from glycolaldehyde-modified proteins
Identification in human atherosclerotic lesions of GA-pyridine, a novel structure derived from glycolaldehyde-modified proteins
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DOI：
10.1074/jbc.m205688200
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发表时间：
2002-12-13
影响因子：
4.8
通讯作者：
Horiuchi, S
中科院分区：
文献类型：
--
作者：
Nagai, R;Hayashi, CM;Horiuchi, S
乙醇醛（GA）是由丝氨酸通过髓过氧化物酶的作用形成的，并与蛋白质反应形成几种产物。其中突出的是N-β-（羧甲基）赖氨酸（CML），其也被称为晚期糖基化终产物之一。由于CML是由广泛的前体形成的，我们试图确定GA与蛋白质反应的独特结构特征。为此，制备了对GA修饰的蛋白质具有特异性的单克隆（GA 5和1A 12）和多克隆（非CML-GA）抗体。这些抗体与GA修饰的BSA和次氯酸修饰的BSA特异性反应，但不与其他醛修饰的BSA反应，表明这些抗体的表位可能是髓过氧化物酶诱导的蛋白质修饰的特异性标记。通过HPLC纯化GA-修饰的N-α-（苄氧羰基）-L-赖氨酸，分离出GA 5-反应性化合物，其化学结构表征为3-羟基-4-羟甲基-1-（5-氨基-5-羧基戊基）吡啶鎓阳离子。该化合物被命名为GA-吡啶，其被1A 12和非CML-GA识别，表明GA-吡啶是GA修饰蛋白中的重要抗原结构。免疫组化研究表明，GA-吡啶的积累在泡沫细胞的细胞质和细胞外的中心区域的粥样硬化在人类动脉粥样硬化病变。这些结果表明，髓过氧化物酶介导的蛋白质修饰通过GA可能有助于动脉粥样硬化。
Glycolaldehyde (GA) is formed from serine by action of myeloperoxidase and reacts with proteins to form several products. Prominent among them is N-epsilon-(carboxymethyl)lysine (CML), which is also known as one of the advanced glycation end products. Because CML is formed from a wide range of precursors, we have attempted to identify unique structures characteristic of the reaction of GA with protein. To this end, monoclonal (GA5 and 1A12) and polyclonal (non-CML-GA) antibodies specific for GA-modified proteins were prepared. These antibodies specifically reacted with GA-modified and with hypochlorous acid-modified BSA, but not with BSA modified by other aldehydes, indicating that the epitope of these antibodies could be a specific marker for myeloperoxidase-induced protein modification. By HPLC purification from GA-modified N-alpha-(carbobenzyloxy)-L-lysine, GA5-reactive compound was isolated, and its chemical structure was characterized as 3-hydroxy-4-hydroxymethyl-l-(5-amino-5-carboxypentyl) pyridinium cation. This compound named as GA-pyridine was recognized both by 1A12 and non-CML-GA, indicating that GA-pyridine is an important antigenic structure in GA-modified proteins. Immunohistochemical studies with GA5 demonstrated the accumulation of GA-pyridine in the cytoplasm of foam cells and extracellularly in the central region of atheroma in human atherosclerotic lesions. These results suggest that myeloperoxidase-mediated protein modification via GA may contribute to atherogenesis.