LOX-1 Ligands Containing Apolipoprotein B and Carotid Intima-media Thickness in Middle-aged Community-dwelling US Caucasian and Japanese Men

Abstract

Objective-The serum level of LOX-1 ligand containing ApoB (LAB) may reflect atherogenicity better than LDL cholesterol (LDLC), total LDL particles and usual measurement of oxidized LDL. The association between LAB and intima-media thickness (IMT) of carotid artery was investigated by ultrasound in US and Japan men.Methods-Participants were 297 US Caucasian and 310 Japanese men, aged 40 to 49 years without past history of cardiovascular disease. Serum LAB levels were measured by ELISAs with recombinant LOX-1 and monoclonal anti-apolipoprotein B antibody.Address for Correspondence: Tomonori Okamura, Department of Preventive Medicine and Public Health, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan, okamura@z6.keio.jp, Phone: +81-3-5363-3759, Fax: +81-3-3359-3686. Conflict of interestInvestigators of LDL-C Study Group received no remuneration for conducting this study. NIH Public Access

LOX-1 in atherosclerotic disease

“…In a study of 236 healthy male employees [57], after adjustment for age, drinking, physical activity and body mass index (BMI), smoking was positively associated with serum LAB levels, which were significantly higher in heavy smokers (20 cigarettes per day and greater) than in non-smokers. A positive association between LAB quartiles and prevalence of smoking was also observed in US men aged 40-49 years [53]; however, this association was not observed in Japanese men of the same age in whom the prevalence of smoking was very high (49%). The above-mentioned studies suggest that smoking might increase serum levels of sLOX-1 and LAB.…”

“…In US men, serum LAB showed a significant positive association with carotid intima-media thickness (IMT) that was independent of LDLC; however, there was no association between LAB and carotid IMT in Japanese [53]. Furthermore, there was no association between serum sLOX-1 levels and carotid IMT in either population.…”

“…In the ERA JUMP (Electron-Beam Tomography, Risk Factor Assessment Among Japanese and U.S. Men in the Post-World War II Birth Cohort) study [51][52][53], a cross-sectional investigation comparing subclinical atherosclerotic findings between community-dwelling US and Japanese men aged 40-49 years, the serum levels of sLOX-1 and LAB were significantly higher in US men than in Japanese men. In US men, serum LAB showed a significant positive association with carotid intima-media thickness (IMT) that was independent of LDLC; however, there was no association between LAB and carotid IMT in Japanese [53].…”