Direct and Simple Fluorescence Detection Method for Oxidized Lipoproteins

摘要

The quantification of low-density lipoprotein (LDL) andnhigh-density lipoprotein (HDL) is currently one of thenmost important clinical measurements for characterizingnmetabolic syndrome. However, recent studies have revealednadditional factors that may be more stronglynassociated with the coronary heart disease than simplenmeasurement of LDL or HDL levels, such as small densen(sd) LDL particles and oxidized LDL or HDL particles.nAlthough several methods using enzyme-antibody detectionnsystems or fluorescent probes have been devised toncharacterize these factors, such methods are expensivento implement for clinical measurements. Here, we presentna straightforward analytical method for direct quantitationnof oxidized lipoproteins by fluorescence spectrometry,nwith excitation in the UV (365 ( 10 nm) or visible (470n( 10 nm) range and emission detected at 450 ( 30 nmnor 535 ( 15 nm. This method can be readily applied fornclinical measurement in patients with dyslipidemia usingnonly 1 μL of 1 mg/mL of lipoprotein and without the neednfor any expensive detection antibodies. Using this newntechnique, biological samples from patients with dyslipidemianshowed higher fluorescence intensities than samplesnfrom normal subjects when detecting oxidized LDL andnlight HDL (d ) 1.063-1.125 g/mL), whereas samplesnfrom patients with dyslipidemia showed lower fluorescencenintensities than samples from normal subjects whennmeasuring oxidized heavy HDL (d ) 1.125-1.210 g/mL)nlevels.