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Modulation of irinotecan-induced genomic DNA damage by theanine

Sabry Attia1

  • 1Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, PO Box 2457, Riyadh, Saudi Arabia. attiasm@ksu.edu.sa

Food and Chemical Toxicology : an International Journal Published for the British Industrial Biological Research Association
|March 15, 2012
PubMed

Insights

Theanine protects mouse bone marrow cells from irinotecan-induced DNA damage. This chemoprotective effect is linked to theanine

Area of Science:

  • Biochemistry
  • Genotoxicology
  • Pharmacology

Background:

  • Irinotecan is a chemotherapy drug that can cause genomic DNA damage.
  • Oxidative stress is implicated in irinotecan-induced genotoxicity.
  • Theanine is an amino acid with potential antioxidant properties.

Purpose of the Study:

  • To investigate the chemoprotective activity of theanine against irinotecan-induced genomic DNA damage in mouse bone marrow cells.
  • To explore the underlying mechanisms of theanine's protective effects.

Main Methods:

  • Mice were treated with theanine and/or irinotecan.
  • Genomic damage was assessed using chromosomal aberrations, DNA damage assays, micronuclei formation, and mitotic activity.
  • Oxidative DNA stress markers (8-hydroxydeoxyguanosine, lipid peroxidation, glutathione levels) were measured.

Main Results:

  • Theanine was found to be neither genotoxic nor cytotoxic in mice.
  • Theanine pretreatment significantly reduced irinotecan-induced genomic damage in a dose-dependent manner.
  • Theanine ameliorated irinotecan-induced oxidative DNA stress markers.

Conclusions:

  • Theanine exhibits chemoprotective activity against irinotecan-induced genomic damage in mouse bone marrow.
  • The protective mechanism involves modulating cellular antioxidant levels and mitigating oxidative DNA stress.
  • Theanine offers a potential strategy to protect against irinotecan genotoxicity.

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