Novel fluorescently labeled peptide compounds for detection of oxidized low-density lipoprotein at high specificity.
The probes for specific detection of oxidized low-density lipoprotein (ox-LDL) in plasma and in atherosclerotic plaques are expected to be useful for the identification, diagnosis, prevention, and treatment for atherosclerosis. In this study, to develop a fluorescent peptide probe for specific detection of ox-LDL, we investigated the interaction of fluorescein isothiocyanate (FITC)-labeled peptides with ox-LDL using polyacrylamide gel electrophoresis. Two heptapeptides (KWYKDGD and KP6) coupled through the ε-amino group of K at the N-terminus to FITC in the presence/absence of 6-amino-n-caproic acid (AC) linker to FITC--(FITC-AC)KP6 and (FITC)KP6--both bound with high specificity to ox-LDL in a dose-dependent manner. In contrast, a tetrapeptide (YKDG) labeled with FITC at the N-terminus and a pentapeptide (YKDGK) coupled through the ε-amino group of K at the C-terminus to FITC did not bind selectively to ox-LDL. Furthermore, (FITC)KP6 and (FITC-AC)KP6 bound with high specificity to the protein in mouse plasma (probably ox-LDL fraction). These findings strongly suggest that (FITC)KP6 and (FITC-AC)KP6 may be effective novel fluorescent probes for specific detection of ox-LDL.
Faculty of Pharmacy, Iwaki Meisei University, 5-5-1, Chuodai-Iino, Iwaki, Fukushima, 970-8551, Japan.
Akira
A
Sato
Hikaru
H
Yamanaka
Keitaro
K
Oe
Yoji
Y
Yamazaki
Keiichi
K
Ebina
D000595:Amino Acid Sequence; D000818:Animals; D002208:Caproates / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry*; D008077:Lipoproteins, LDL / Q000097:blood*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry*; D010084:Oxidation-Reduction; D011485:Protein Binding
D002208:Caproates; D008077:Lipoproteins, LDL; D009842:Oligopeptides; C099252:oxidized low density lipoprotein; C037652:hexanoic acid; D016650:Fluorescein-5-isothiocyanate
Asp-hemolysin; atherosclerosis; fluorescent probe; oxidized LDL; synthetic peptide