Abstract
Most studies of antibodies to oxidized LDL have been undertaken in patients with different diseases and cardiovascular risk factors. However, very few studies have researched the distribution and determining factors of antibodies to oxidized LDL in the general population. A total of 1,354 persons (817 females and 537 males) aged 5–65 years were included in this study. They were selected randomly from the population census of Malaga, in southern Spain. The females had lower levels of total cholesterol and triglycerides and higher levels of HDL-cholesterol and a very significant increase ( P 0.0001) in levels of anti-oxidized LDL [low density lipoprotein modified by malondialdehyde (MDA-LDL)] antibodies but no difference in levels of immune complexes consisting of LDL and IgG antibodies (anti-LDL immune complex). Younger persons (16–35 years) had higher levels of anti-oxidized LDL (MDA-LDL) antibodies than persons older than 35 years ( P 0.05). Levels of immune complexes were significantly higher ( P 0.05) in persons aged 5–15 years than in persons older than 40 years. A very weak association was found between levels of anti-oxidized LDL (MDA-LDL) antibodies and anti-LDL immune complexes. The higher prevalence of anti-oxidized LDL (MDA-LDL) antibodies in females and young persons is in agreement with studies that found an inverse association between atherosclerosis and the level of these antibodies. —Tinahones, F. J., J. M. GomezZumaquero, L. Garrido-Sanchez, E. Garcia-Fuentes, G. RojoMartinez, I. Esteva, M. S. Ruiz de Adana, F. Cardona, and F. Soriguer. Influence of age and sex on levels of anti-oxidized LDL antibodies and anti-LDL immune complexes in the general population. J. Lipid Res. 2005. 46: 452–457. Supplementary key words low density lipoprotein • oxidized low density lipoproteins • atherosclerosis Several lines of evidence have determined that the oxidized products of LDLs are involved in atherogenesis (1, 2). Oxidative modification of LDLs may be a prerequisite for the rapid accumulation of LDLs within macrophages to form foam cells; indeed, oxidized LDL has been found in extracts from atherosclerotic lesions (3). Oxidative modification of LDLs induces the formation of immunogenic epitopes in the LDL molecule, which leads to the formation of antibodies against oxidized LDLs that can be detected in serum (4). These antibodies have been detected in patients with advanced atherosclerotic lesions (5). Levels of anti-oxidized LDL antibodies are increased in patients with coronary atherosclerosis (6, 7), acute myocardial infarction (8), and cerebral or peripheral vascular disease (9), and they have been shown to predict the progression of carotid atherosclerotic lesions (10). Nevertheless, the clinical importance of these autoantibodies is still under discussion. For example, in patients with diabetes, no association has been found between antioxidized LDL antibodies and microvascular complications (11), nor has an association been found between their levels and levels of cholesterol in patients with heterozygous hypercholesterolemia (12) or with the degree of oxidizability in serum (13). In fact, our group found an inverse relation between levels of cholesterol and levels of antioxidized LDL antibodies in the general population (14). Recent studies have found no association between the levels of anti-oxidized LDL antibodies and coronary artery disease (15), and others have detected an inverse relation between IgM autoantibodies to oxidized LDL and carotid artery atherosclerosis (16). The methodological approach for the detection of antioxidized LDL antibodies is subject to much variation. Moreover, oxidized LDL autoantibodies have been found both free and forming immune complexes (17). Thus, difAbbreviations: MDA, malondialdehyde; MDA-LDL, low density lipoprotein modified by malondialdehyde. 1 To whom correspondence should be addressed. e-mail: fjtinahones@terra.es Manuscript received 2 August 2004 and in revised form 22 October 2004 and in re-revised form 8 December 2004. Published, JLR Papers in Press, December 16, 2004. DOI 10.1194/jlr.M400290-JLR200 by gest, on Jne 7, 2013 w w w .j.org D ow nladed fom
Published Version
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