Increased cerebral oxidative damage and decreased antioxidant defenses in ovariectomized and sham-operated rats supplemented with vitamin A

Cell Biol Toxicol. 2012 Oct;28(5):317-30. doi: 10.1007/s10565-012-9226-x. Epub 2012 Jul 18.

Abstract

Previous studies have linked oxidative stress with aging and aging-related processes, including menopause. Abnormalities in the redox state similar to those observed in menopausal women can be modeled experimentally with rat ovariectomy. The aim of the present study was to investigate the effects of vitamin A (retinol palmitate) supplementation (500 or 1,500 IU kg(-1) day(-1) for 30 days) on behavioral parameters and brain redox profile in ovariectomized (OVX) and sham-operated rats. Ovariectomy caused pronounced uterine atrophy and decreased locomotor/exploratory activity. Moreover, we found increased hypothalamic and frontal cortex superoxide dismutase/catalase (SOD/CAT) ratio and decreased hippocampal thiol content, accompanied by increased frontal cortex lipid oxidative damage (TBARS) in OVX rats. Vitamin A at 1,500 IUkg(-1) day(-1) decreased exploratory behavior and decreased total hippocampal thiol content in sham-operated rats, increased hippocampal SOD/CAT ratio and decreased total antioxidant potential in the hippocampus of both sham and OVX groups, and increased cortical TBARS levels in OVX rats. Thus, vitamin A may induce a pro-oxidant state in discrete brain regions of sham-operated and OVX rats. These results suggest some caution regarding the use of high doses of vitamin A supplementation during menopause.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / adverse effects*
  • Catalase / metabolism
  • Cerebral Cortex / drug effects*
  • Cerebral Cortex / metabolism
  • Dietary Supplements / adverse effects*
  • Exploratory Behavior / drug effects
  • Female
  • Hippocampus / drug effects*
  • Hippocampus / metabolism
  • Humans
  • Hypothalamus / drug effects*
  • Hypothalamus / metabolism
  • Lipid Peroxidation / drug effects
  • Menopause / metabolism
  • Models, Animal
  • Motor Activity / drug effects
  • Ovariectomy
  • Oxidative Stress
  • Rats
  • Rats, Wistar
  • Superoxide Dismutase / metabolism
  • Thiobarbituric Acid Reactive Substances / analysis
  • Vitamin A / adverse effects*

Substances

  • Antioxidants
  • Thiobarbituric Acid Reactive Substances
  • Vitamin A
  • Catalase
  • Superoxide Dismutase