Szwergold Benjamin S
Department of Medicine, Dartmouth Medical School, Hanover, NH, USA.
Biochem Biophys Res Commun. 2005 Oct 14;336(1):36-41. doi: 10.1016/j.bbrc.2005.08.033.
There are numerous publications describing the positive effects of carnosine (beta-alanyl-histidine) and anserine (beta-alanyl-1-N-methyl-histidine) on cell and organ function. Of special interest to us is the fact that these dipeptides act to retard and (in one instance) reverse non-enzymatic glycation. To date, the primary explanation for these anti-glycating effects has been the fact that carnosine and anserine can serve as alternative and competitive glycation targets, thereby protecting proteins from this deleterious process. In this paper, we document another mechanism by which these two peptides can retard or reverse glycation. The process involves decomposition of the very first intermediates of the non-enzymatic glycation cascade (aldosamines a.k.a. Schiff bases) by nucleophilic attack of carnosine and/or anserine on the preformed aldosamine such as glucosyl-lysine. If future research shows this reaction is to be physiologically important, this mechanism could explain some of the beneficial effects of carnosine and anserine as anti-glycating agents.
有大量出版物描述了肌肽（β-丙氨酰组氨酸）和鹅肌肽（β-丙氨酰-1-N-甲基组氨酸）对细胞和器官功能的积极影响。我们特别感兴趣的是，这些二肽具有延缓（在一个实例中是逆转）非酶糖基化的作用。迄今为止，对这些抗糖基化作用的主要解释是，肌肽和鹅肌肽可以作为替代性的竞争性糖基化靶点，从而保护蛋白质免受这一有害过程的影响。在本文中，我们记录了这两种肽延缓或逆转糖基化的另一种机制。该过程涉及肌肽和/或鹅肌肽对预先形成的醛糖胺（如葡糖基赖氨酸）进行亲核攻击，分解非酶糖基化级联反应的最初中间体（醛糖胺，又称席夫碱）。如果未来的研究表明这种反应在生理上很重要，那么这种机制可以解释肌肽和鹅肌肽作为抗糖基化剂的一些有益作用。
