title: A novel biomarker for hyperglycemia, MRX isolated from hydrolysate of glycated proteins.
abstract: Long-lived proteins can undergo non-enzymatic glycation to form highly crosslinked structures with characteristic fluorescence during aging and diabetes processes. In this paper, a typical fluorophore, named Maillard reaction product X (MRX), was isolated from the hydrolysate of glycated proteins. MRX could be formed by incubation of bovine serum albumin with glucose, followed by acid hydrolysis. The structure of MRX was determined to be 8-hydroxy-5-methyldihydrothiazolo[3,2-alpha] pyridinium-3-carboxylate. MRX was also found to be formed by the incubation of cysteine and arginine with glucose, followed by hydrolysis. We found the formation of MRX in the recently developed genetically diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and compared them with that in the control Long-Evans Tokushima Otsuka (LETO) rats. Significantly higher levels of MRX were observed from the serum (p < 0.005) and urinary protein (p < 0.001) of OLETF rats in comparison with those of LETO rats. MRX must be a potential candidate as a biomarker for hyperglycemia.
authors.affiliation: Laboratory of Food and Biodynamics, Nagoya University School of Agricultural Sciences, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Oya
authors.forename: H
authors.initials: H
authors.lastname: Kumon
authors.forename: H
authors.initials: H
authors.lastname: Kobayashi
authors.forename: M
authors.initials: M
authors.lastname: Akiba
authors.forename: T
authors.initials: T
authors.lastname: Hosokawa
authors.forename: N
authors.initials: N
authors.lastname: Kakimoto
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Morimitsu
authors.forename: T
authors.initials: T
authors.lastname: Osawa
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood / Q000737:chemistry / Q000652:urine; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000235:genetics / Q000652:urine; D005456:Fluorescent Dyes / Q000737:chemistry / Q000302:isolation & purification; D006023:Glycoproteins / Q000097:blood / Q000737:chemistry* / Q000652:urine; D006031:Glycosylation; D006868:Hydrolysis; D006943:Hyperglycemia / Q000097:blood* / Q000652:urine*; D015416:Maillard Reaction; D008297:Male; D011726:Pyridinium Compounds / Q000737:chemistry* / Q000302:isolation & purification; D051381:Rats; D013844:Thiazoles / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: C112445:8-hydroxy-5-methyldihydrothiazolo(3,2-a)pyridinium-3-carboxylate; D015415:Biomarkers; D005456:Fluorescent Dyes; D006023:Glycoproteins; D011726:Pyridinium Compounds; D013844:Thiazoles