Pro-oxidant effect of alpha-tocopherol in patients with type 2 diabetes after an oral glucose tolerance test--a randomised controlled trial

Cardiovasc Diabetol. 2007 Feb 22:6:8. doi: 10.1186/1475-2840-6-8.

Abstract

Background: As a part of a larger study investigating the effects of alpha-tocopherol on gene expression in type 2 diabetics we observed a pro-oxidant effect of alpha-tocopherol which we believe may be useful in interpreting outcomes of large intervention trials of alpha-tocopherol.

Methods: 19 type 2 diabetes subjects were randomised into two groups taking either 1200 IU/day of alpha-tocopherol or a matched placebo for 4 weeks. On day 0 and 29 of this study oxidative DNA damage was assessed in mononuclear cells from fasted blood samples and following a 2 h glucose tolerance test (GTT).

Results: On day 0 there was no significant difference in oxidative DNA damage between the two groups or following a GTT. On day 29 there was no significant difference in oxidative DNA damage in fasted blood samples, however following a GTT there was a significant increase in oxidative DNA damage in the alpha-tocopherol treatment group.

Conclusion: High dose supplementation with alpha-tocopherol primes mononuclear cells from patients with type 2 diabetes for a potentially damaging response to acute hyperglycaemia.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • DNA / metabolism
  • DNA Damage*
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / diagnosis*
  • Diabetes Mellitus, Type 2 / genetics*
  • Dose-Response Relationship, Drug
  • Fasting / blood
  • Female
  • Fluorescence
  • Glucose Tolerance Test*
  • Guanine / analogs & derivatives
  • Humans
  • Middle Aged
  • Monocytes / drug effects
  • Monocytes / physiology
  • Oxidants / administration & dosage
  • Oxidants / pharmacology*
  • Oxidation-Reduction / drug effects
  • Time Factors
  • alpha-Tocopherol / administration & dosage
  • alpha-Tocopherol / pharmacology*

Substances

  • Oxidants
  • 8-hydroxyguanine
  • Guanine
  • DNA
  • alpha-Tocopherol