Role ofβ₂-Glycoprotein I, LDL-, and Antioxidant Levels in Hypercholesterolemic Elderly Subjects

Abstract

The levels of electronegative low-density lipoprotein (LDL-), LDL cholesterol oxidability, and plasma levels of molecular antioxidants and of beta(2)-glycoprotein I (beta(2) GPI) were studied in a group of 10 hypercholesterolemic (HC) and 10 normocholesterolemic (NC) elderly subjects. HC subjects showed significantly higher levels of cholesterol, LDL cholesterol, LDL-, and beta(2)GPI than NC, whereas high-density lipoprotein cholesterol and alpha-tocopherol levels were lower in HC as compared with NC subjects. Correlations among LDL- levels, LDL oxidation lag time, beta(2)GPI, and antioxidant plasma levels were studied in 100 HC elderly subjects. Lag time for in vitro LDL oxidation positively correlated with ubiquinol-10 levels (p = 0.008), but not with other antioxidants studied or beta(2)GPI. LDL- and alpha-tocopherol levels showed an inverse and significant correlation (p = 0.018). beta(2)GPI and LDL cholesterol levels were correlated (p = 0.001), whereas no significance was found between LDL- and beta(2)GPI levels (p = 0.057). The physiological significance of alpha-tocopherol and ubiquinol-10 levels on LDL- levels, and the presence of high levels of beta(2)-GPI, are discussed in terms of protective mechanisms operating during the overall atherosclerosis process.

Underlying Factors Associated with Anemia in Amazonian Children: A Population-Based, Cross-Sectional Study

“…Serum folate and vitamin B 12 concentrations were measured using commercial fluoroimmunoassays (Perkin Elmer, Wallac Oy, Turku, Finland); values <10 nmol/L and <150 pmol/L were considered diagnostic of folate and vitamin B 12 deficiency, respectively [22]. Serum concentrations of vitamin A (retinol) were measured by standard HPLC methods [23]; concentrations of <0.70 µmol/L were considered diagnostic of vitamin A deficiency [24]. Frozen samples were analyzed within 6 months of collection.…”

C-Reactive Protein Concentration Predicts Change in Body Mass Index during Childhood

“…Plasma ferritin and soluble transferrin receptor were measured with enzyme immunoassays (Ramco, Houston, TX, USA) to determine iron deficiency (soluble transferrin receptor >8.3 mg/L, or ferritin <12 µg/L for children aged up to 5 years or <15 µg/L for those above 5 years) [26). Serum vitamin A (retinol) was measured using standard HPLC methods [27], to determine vitamin A deficiency (<0.70 µmol/L) [28].…”

Aging and oxidative stress

“…Blood samples were taken on heparin, after 12 h fasting. Plasma was separated from red blood cells by conventional centrifugation, was stored (maximum 48 h) for nutritional antioxidants (Gomes et al, 2004), and TBARS (Ohkawa et al, 1979) measurements. Red blood cells were processed for Cu, Zn-superoxide dismutase (McCord and Fridovich, 1969), catalase (Beutler, 1975), and glutathione peroxidase activity measurements.…”