Increased Lipid Peroxidation in Serum and Low-Density Lipoproteins Associated with Aging in Humans

Abstract

This study was carried out in 140 healthy subjects who were divided into three subgroups of age: young (21-40 years), mature (41-60 years), and elderly (61-85 years) to investigate lipid peroxides and the antioxidant system in serum and low-density lipoproteins (LDL). Serum levels of cholesterol and LDL-cholesterol increased with age. The elderly group was found to have higher polyunsaturated fatty acid (PUFA) levels, thiobarbituric acid reactive substances (TBARS), diene conjugates, and lower cholesterol-adjusted vitamin E levels and antioxidant activity (AOA) as compared to the young group. No age-related difference was detected in serum vitamin C levels. Age correlated positively with serum cholesterol, LDL-cholesterol, PUFA, TBARS, diene conjugates, and negatively with cholesterol-adjusted vitamin E levels and AOA. In addition, endogenous LDL diene conjugate levels and the susceptibility of LDL to copper-induced lipid peroxidation increased in elderly subjects as compared with young subjects. In addition, positive correlations were detected between age and LDL endogenous diene conjugate levels and TBARS formation after copper incubation. However, the susceptibility of whole serum to copper-induced lipid peroxidation did not change in young and elderly subjects. Our results show that endogenous lipid peroxide levels in serum and LDL, and the susceptibility of LDL to copper-induced oxidation, increased with aging in humans.

RETRACTED ARTICLE: Aging decreases rate of docosahexaenoic acid synthesis-secretion from circulating unesterified α-linolenic acid by rat liver

“…In another study in Fischer-344 rats, total plasma PUFA percent composition increased with age (Engler et al 1998). In humans, total unesterified fatty acid concentrations increased with age (Bonadonna et al 1994), as did EPA and DHA concentrations in plasma total lipids (Balkan et al 2002;Fortier et al 2010). The inconsistency in study outcomes may relate to differences in DHA synthesis capacity between rodents and humans (Wang et al 2006), diet, or the fact that most studies measured n-3 PUFA concentrations in plasma total lipid instead of esterified and unesterified fractions (Engler et al 1998;Fortier et al 2010).…”

Evaluation of Salivary Total Antioxidant Capacity in Smokers with Severe Chronic Periodontitis

“…In agreement with this theory, Balkan et al revealed that antioxidant activities in elderly subjects (61 to 85 years old) were lower than young people (32).…”

Effects of oral contraception with ethinylestradiol and drospirenone on oxidative stress in women 18–35 years old

“…Nothing is known about an age-related effect on the studied parameters in this range of age. Increased plasma levels of lipid peroxides and Cu have manly been shown in elderly [65][66][67]. If there is a positive correlation between age and the variables measured, the effect we have seen might be underestimated.…”