title: Oxidation of serum low-density lipoprotein (LDL) and antioxidant status in young and elderly humans.
abstract: The incidence of atherosclerosis increases with age, as do various indices of free-radical mediated damage, e.g., lipid peroxidation. Because lipid peroxidation plays a prominent role in lipoprotein oxidation, likely a prelude to atherosclerosis, we compared the susceptibility of lipoproteins to oxidation in young (19-30 years) and elderly (59-86 years) groups. Although we found no significant differences in serum malondialdehyde (MDA) or oxidized LDL antibodies (OLAB) between young and elderly lipoproteins, MDA was directly related to OLAB regardless of age (r = 0.322, p = 0.005) and there was a trend for lower OLAB levels (30.5%, p = 0.079) in the elderly compared to the young population. Overall, serum antioxidant status was either similar or greater in the elderly group compared to the young group, likely reflecting antioxidant supplementation by the elderly group. OLAB was inversely related to Vitamin C (r = -0.310, p = 0.008) and Vitamin E intake (r = -0.277, p = 0.018) from foods and supplements. Serum levels of Vitamin C and Vitamin E were significantly higher (18.5%, p = 0.021 and 58.1 %, p < 0.001, respectively) in the elderly group compared to the young group and the ratio of Vitamin E to Vitamin C was significantly higher (30.4%, p = 0.042) in the serum of the elderly group. Oxidation of serum LDL and antioxidant status were not affected by age; however, the ratio of serum Vitamin E to Vitamin C was higher in the elderly group which may affect Vitamin E recycling.
authors.affiliation: Department of Nutrition, Mail Stop 142, University of Nevada, Reno 89557, USA.
authors.forename: Yukiko K
authors.initials: YK
authors.lastname: Nakamura
authors.forename: Marsha H
authors.initials: MH
authors.lastname: Read
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Elias
authors.forename: Stanley T
authors.initials: ST
authors.lastname: Omaye
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000378:metabolism*; D000975:Antioxidants / Q000378:metabolism*; D001205:Ascorbic Acid / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood*; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D010084:Oxidation-Reduction; D014810:Vitamin E / Q000097:blood
chemical_list: D000975:Antioxidants; D008078:Cholesterol, LDL; D014810:Vitamin E; D008315:Malondialdehyde; D001205:Ascorbic Acid