N-epsilon-(carboxyethyl)lysine, a product of the chemical modification of proteins by methylglyoxal, increases with age in human lens proteins
N-epsilon-(carboxyethyl)lysine, a product of the chemical modification of proteins by methylglyoxal, increases with age in human lens proteins
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DOI：
10.1042/bj3240565
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发表时间：
1997-06-01
影响因子：
4.1
通讯作者：
Baynes, JW
中科院分区：
文献类型：
--
作者：
Ahmed, MU;Frye, EB;Baynes, JW
晚期糖基化终产物和糖基氧化产物，如N-β-（羧甲基）赖氨酸（CML）和戊糖苷，随着年龄的增长在长寿命组织蛋白中积累，并与组织蛋白的老化和糖尿病、动脉粥样硬化和其他疾病的病理学发展有关。在本文中，我们描述了一种新的晚期糖基化终产物，N-羧乙基赖氨酸（CEL），它是在甲基乙二醛与模型化合物和蛋白质RNase和胶原蛋白中的赖氨酸残基反应过程中形成的。在人透镜蛋白中也检测到浓度与CML相似的CEL，并且与CML浓度平行地随年龄增加。尽管CEL在丙酮醛和磷酸丙糖与赖氨酸和蛋白质的反应期间以最高产率形成，但它也在戊糖、抗坏血酸和其他糖与赖氨酸和RNA酶的反应中形成。我们建议CML和CEL的水平和它们在组织蛋白和尿液中的比例将提供组织中乙二醛和甲基乙二醛浓度的指数，疾病中谷胱甘肽稳态和二羰基代谢的改变，以及衰老和疾病中组织蛋白中晚期糖基化终产物的来源。
Advanced glycation end-products and glycoxidation products, such as N-epsilon-(carboxymethyl)lysine (CML) and pentosidine, accumulate in long-lived tissue proteins with age and are implicated in the aging of tissue proteins and in the development of pathology in diabetes, atherosclerosis and other diseases. In this paper we describe a new advanced glycation end-product, N-epsilon(carboxyethyl)lysine (CEL), which is formed during the reaction of methylglyoxal with lysine residues in model compounds and in the proteins RNase and collagen. CEL was also detected in human lens proteins at a concentration similar to that of CML, and increased with age in parallel with the concentration of CML. Although CEL was formed in highest yields during the reaction of methylglyoxal and triose phosphates with lysine and protein, it was also formed in reactions of pentoses, ascorbate and other sugars with lysine and RNase. We propose that levels of CML and CEL and their ratio to one another in tissue proteins and in urine will provide an index of glyoxal and methylglyoxal concentrations in tissues, alterations in glutathione homoeostasis and dicarbonyl metabolism in disease, and sources of advanced glycation end-products in tissue proteins in aging and disease.