title: Highly stable, fluorescence-labeled heptapeptides substituted with a D-amino acid for the specific detection of oxidized low-density lipoprotein in plasma.
abstract: Probes that can detect oxidized low-density lipoprotein (ox-LDL) in plasma and in atherosclerotic plaques can be useful for the diagnosis, prevention, and treatment of atherosclerosis. Recently, we have reported that two heptapeptides (Lys-Trp-Tyr-Lys-Asp-Gly-Asp, KP6) coupled to fluorescein isothiocyanate (FITC) through the ε-amino group of N-terminus Lys in the absence/presence of 6-amino-n-caproic acid (AC) linker to FITC-(FITC)KP6 and (FITC-AC)KP6-can be useful as fluorescent probes for the specific detection of ox-LDL. In this study, to develop the fluorescent peptides with high plasma stability for the specific detection of ox-LDL, we investigated the interaction of (FITC)KP6 and (FITC-AC)KP6 substituted with D-Lys at the N-terminus-(FITC)dKP6 and (FITC-AC)dKP6-with ox-LDL, and the in vitro stability of these peptides in mouse plasma. (FITC)dKP6 and (FITC-AC)dKP6 bound with high specificity to ox-LDL in a dose-dependent manner, and also to ox-LDL in the mouse plasma. Furthermore, (FITC)dKP6 was more stable than (FITC)KP6 in mouse plasma (102.1% versus 69.0% remained after 1 h). These findings strongly suggest that (FITC)dKP6 and (FITC-AC)dKP6 may be effective fluorescent probes with higher plasma stability than (FITC)KP6 and (FITC-AC)KP6 for the specific detection of ox-LDL.
authors: Faculty of Pharmacy, Iwaki Meisei University, 5-5-1, Chuodai-Iino, Iwaki, Fukushima, 970-8551, Japan.
authors: Akira
authors: A
authors: Sato
authors: Hikaru
authors: H
authors: Yamanaka
authors: Keitaro
authors: K
authors: Oe
authors: Izumi
authors: I
authors: Yokoyama
authors: Yoji
authors: Y
authors: Yamazaki
authors: Keiichi
authors: K
authors: Ebina
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry*; D008077:Lipoproteins, LDL / Q000097:blood*; D008239:Lysine / Q000737:chemistry*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry*; D055550:Protein Stability
chemical_list: D008077:Lipoproteins, LDL; D009842:Oligopeptides; C099252:oxidized low density lipoprotein; D016650:Fluorescein-5-isothiocyanate; D008239:Lysine
keywords: D-amino acid; atherosclerosis; fluorescent probe; oxidized LDL; plasma stability; synthetic peptide