Increased susceptibility of low‐density lipoprotein (LDL) to oxidation by γ‐radiolysis with age

Abstract

examine the effect of age on the susceptibility to free radical Abstract The susceptibifity to oxidation of freshly isolated oxidation of LDL. To this end, we compared the susceptibility LDL from healthy normolipidemic individuals in three age groups was estimated by exposure of LDL to ionizing radiation of LDL isolated from healthy, normolipidemic individuals followed by analyses of vitamin E, TBARS, conjugated dienes, toward radiation-induced oxidation in an attempt to find facand fluorescent products. The results clearly showed that LDL tors responsible for the association of atherosclerosis with from elderly subjects was the most susceptible to oxidative aging. damage in vitro. In particular, the greater susceptibifity of LDL from elderly subjects in comparison to that from young subjects may be attributed to the much lower (4-fold) concentration of 2. Materials and methods LDL vitamin E in the elderly subjects. The present study reinforces the notion that the susceptibility of LDL to oxidation 2.1. Reagents increases with age.Acetic acid, sulfuric acid n-butanol, sodium phosphate, thiobarbituric acid, methanol and hexane were purchased from Fisher (Mont-

Detection of Oxidant-Induced Slight Chromosomal Damage in Cells by Subsequent Exposure to X-Rays.

“…10) The results of other researchers who examined the enhanced oxidizability of lipoprotein 7,8) and red blood cells 9) after g-ray exposure in vitro may be in line with the present findings.…”

“…6) This ionizing radiation can be applied as a secondary oxidative stress to amplify slight oxidative damage or oxidative stress occurring in cells or bodies. The g-ray irradiation technique has been used to examine the oxidizability of lipoprotein 7,8) and red blood cells. 9) However, this technique employing ionizing radiation has not been applied for the detection of DNA or chromosome damage, which is important for understanding aging and degenerative diseases.…”

Method of imaging low density lipoproteins by atomic force microscopy

“…Isolation of LDL (1.019 < d < 1.063) and HDL (1.063 < d < 1.21) was performed according to the method of Sattler et al (1994), using a Beckman Optima TLX ultracentrifuge equipped with a TLA 100.4 rotor, in the presence of ethylenediamine tetraacetic acid (0.4 mg/mL) as already described (Khalil et al, 1996(Khalil et al, , 1998. After separation, LDL and HDL were dialyzed overnight at 48C with 10 -2 M sodium phosphate buffer containing 0.15 M NaCl (pH 7.4).…”

Relationship Between the Response to Influenza Vaccination and the Nutritional Status in Institutionalized Elderly Subjects

“…Biochemical-nutritional parameters.-Plasma vitamin E, A and l3-carotene were determined by HPLC as already described (39). Total protein, prealbumin, iron, calcium, TSH, DHEA and DHEAS were measured as routine laboratory tests by the Clinical Biochemistry Laboratory of the University Hospital of Sherbrooke University.…”