Is plasma alpha-tocopherol associated with electronegative LDL in obese adolescents?

J Nutr Sci Vitaminol (Tokyo). 2013;59(2):100-7. doi: 10.3177/jnsv.59.100.

Abstract

Obesity has increased in children and adolescents. What is reflected in the early occurrence of cardiometabolic alterations, like hypertension and type 2 diabetes, where the oxLDL formation is stimulated. Various studies have shown that plasma α-tocopherol (α-TP) can protect LDL against oxidation. Nevertheless, the action of plasma α-TP in cardiovascular diseases remains controversial. We conducted a cross-sectional study to evaluate plasma α-TP and its impact on the concentration of LDL(-). Adolescents (n=150) of both sexes were classified into three groups: healthy weight (HW; 50%), overweight (OV; 22%), and obese (OB; 28%). Lipid profile, LDL(-), anti-oxLDL and anti-LDL(-) antibodies, CRP (ELISA) and plasma α-TP (HPLC) were analyzed. Demographic, anthropometric, and food intake data were evaluated. Crude and energy-adjusted intake of vitamin E in the OB group were higher than in the HW group (p<0.001). Crude and energy-adjusted vitamin E intakes were not correlated with plasma α-TP (r=-0.07; p=0.412 and r=-0.064; p=0.467, respectively). Subjects in the OB group had higher TC and LDL-C and lower HDL-C than in the HW and OV groups. C-reactive protein and anti-oxLDL antibodies changed as a function of BMI. The impact of obesity was reinforced by high values for LDL(-) and low content of plasma α-TP in comparison with the HW (p<0.001) and OV groups (p=0.03). This negative profile was maintained for the ratio between α-TP and TC or LDL-C. Plasma α-TP, α-TP/TC and α-TP/LDL-C were negatively associated with LDL(-) and other cardiometabolic risk factors (BMI, WC, AC and anti-oxLDL). Our results demonstrate that obesity in adolescents is associated with high levels of LDL(-) and low plasma α-TP content.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Anthropometry
  • Body Mass Index
  • C-Reactive Protein / metabolism
  • Child
  • Cholesterol, LDL / blood*
  • Cross-Sectional Studies
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / etiology
  • Dietary Carbohydrates / administration & dosage
  • Dietary Fats / administration & dosage
  • Dietary Proteins / administration & dosage
  • Energy Intake
  • Female
  • Humans
  • Hypertension / blood
  • Hypertension / etiology
  • Lipoproteins, LDL / blood
  • Male
  • Obesity / blood*
  • Obesity / complications
  • Overweight / blood
  • Overweight / complications
  • Risk Factors
  • Surveys and Questionnaires
  • alpha-Tocopherol / blood*

Substances

  • Cholesterol, LDL
  • Dietary Carbohydrates
  • Dietary Fats
  • Dietary Proteins
  • Lipoproteins, LDL
  • oxidized low density lipoprotein
  • C-Reactive Protein
  • alpha-Tocopherol