울릉 마가목의 클로로겐산 이성체의 최종당화산물의 생성 저해 및 라디칼 소거 활성

Abstract

Advanced glycation end product (AGE) formation and reactive oxygen species are potential therapeutic targets for the prevention of diabetic nephropathy and other pathogenic complications. Activity-guided isolation of an ethylacetate-soluble portion of 80% methanolic extract from fruits of Sorbus commixta of the Ulleung Island origin using AGE formation inhibition assay led to the isolation and identification of three caffeoylquinic acid derivatives of a previously known structure, 3-O-caffeoylquinic acid (neochlorogenic acid; 1), 4-O-caffeoylquinic acid (cryptochlorogenic acid; 2), and 5-O-caffeoylquinic acid (chlorogenic acid; 3). The structures of these compounds were confirmed by interpretation of nuclear magnetic resonance and mass spectrometry data. Among the isolates, the major metabolite, neochlorogenic acid (1) showed the most potent inhibitory effect against AGE formation with an IC50 value of 167.5±3.5 μM. Furthermore, all isolated chlorogenic acid isomers were evaluated for their radical scavenging activity against peroxynitrite, and structurally related isomers 1, 2, and 3 exhibited potent inhibitory effects in this radical scavenging assay. This result suggests that the monocaffeoyl quinic acid derivatives isolated from S. commixta might be beneficial for the regulation of diabetic complications and related diseases.