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Subacute effects of methyl parathion on antioxidant defense systems and lipid peroxidation in rats

Ismail Celik1, Huseyin Suzek

  • 1Yüzüncü Yil University, Faculty of Science and Letters, Department of Biology, 65080 Van, Turkey. icelik@yyu.edu.tr

Food and Chemical Toxicology : an International Journal Published for the British Industrial Biological Research Association
|June 24, 2008
PubMed

Insights

Methyl parathion (MP) exposure increased malondialdehyde (MDA) and altered the antioxidant defense system (ADS) in rats. These findings highlight MP

Area of Science:

  • Toxicology
  • Biochemistry
  • Environmental Health

Background:

  • Methyl parathion (MP) is an organophosphate insecticide with known toxicity.
  • Understanding its effects on oxidative stress and antioxidant systems is crucial for risk assessment.

Purpose of the Study:

  • To investigate the impact of sublethal methyl parathion dosages on malondialdehyde (MDA) levels and the antioxidant defense system (ADS) in rat tissues.
  • To assess the effects of chronic MP exposure on reduced glutathione (GSH), glutathione reductase (GR), superoxide dismutase (SOD), and glutathione-S-transferase (GST).

Main Methods:

  • Rats were exposed to 19 mM and 38 mM methyl parathion (MP) in drinking water for 28 days.
  • Malondialdehyde (MDA) content and key antioxidant enzymes (GSH, GR, SOD, GST) were measured in various tissues.

Main Results:

  • MP significantly increased MDA in most tissues, except lungs.
  • SOD levels decreased in lungs but increased in erythrocytes.
  • GR activity decreased in erythrocytes, lungs, and liver (at 38 mM).
  • GST activity increased in most tissues (except liver at 38 mM).
  • GSH levels were significantly depleted in most tissues, excluding lungs.

Conclusions:

  • Sublethal methyl parathion administration promotes malondialdehyde accumulation.
  • MP exposure significantly disrupts the antioxidant defense system in rats.
  • These alterations indicate oxidative stress induced by methyl parathion exposure.

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