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Effects of fluoroquinolones on CYP4501A and 3A in male broilers

Ling-Ling Zhang1, Jun-Ren Zhang, Kuan Guo

  • 1Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.

Research in Veterinary Science
|June 29, 2010
PubMed

Insights

High doses of enrofloxacin and marbofloxacin fluoroquinolones inhibit cytochrome P450 (CYP) enzyme activity and protein levels in broiler chicks. This suggests potential drug-drug interactions, but no changes in mRNA expression were observed.

Area of Science:

  • Pharmacology and Toxicology
  • Veterinary Medicine
  • Biochemistry

Background:

  • Fluoroquinolones are widely used antimicrobials in poultry.
  • Cytochrome P450 (CYP) enzymes are crucial for drug metabolism.
  • Understanding drug interactions is vital for animal health and food safety.

Purpose of the Study:

  • To investigate the inhibitory effects of specific fluoroquinolones on liver CYP1A and CYP3A in broiler chicks.
  • To determine the impact of enrofloxacin, sarafloxacin, and marbofloxacin on CYP enzyme activity, protein, and mRNA levels.
  • To assess the potential for drug-drug interactions in poultry treated with these fluoroquinolones.

Main Methods:

  • Male broiler chicks were administered enrofloxacin, sarafloxacin, or marbofloxacin in drinking water for seven days.
  • CYP1A and CYP3A enzyme activity was assessed using probe drugs (caffeine and dapsone).
  • Western blot analysis and real-time PCR were employed to measure CYP protein and mRNA expression levels.

Main Results:

  • Enrofloxacin significantly increased the elimination half-life of probe drugs and decreased CYP1A and CYP3A protein expression.
  • Marbofloxacin reduced caffeine metabolism and decreased CYP1A protein expression.
  • No significant changes in CYP mRNA expression were observed across all treatment groups.

Conclusions:

  • High doses of enrofloxacin and marbofloxacin inhibit CYP enzyme activity and protein levels in broiler chick liver.
  • Sarafloxacin did not exhibit significant inhibitory effects under the tested conditions.
  • These findings highlight the potential for drug-drug interactions when using enrofloxacin or marbofloxacin concurrently with other substances metabolized by CYP enzymes in poultry.

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