Gastric stability and oral bioavailability of colistin sulfate in pigs challenged or not with Escherichia coli O149: F4 (K88)

Res Vet Sci. 2015 Oct:102:173-81. doi: 10.1016/j.rvsc.2015.08.005. Epub 2015 Aug 9.

Abstract

The aim of the present study was to investigate the in vitro gastric stability of colistin sulfate (CS) and its antimicrobial activity against Escherichia coli and to study the impact of ETEC O149: F4 (K88) infection in pigs on CS intestinal absorption. The stability profile of CS was evaluated in a simulated gastric fluid (SGF). Antimicrobial activity of CS and its degradation products were examined in a 96-well polystyrene microplate model. The effect of experimental infection with ETEC O149: F4 on CS intestinal absorption was determined by quantification of CS systemic concentration using a validated LC-MS/MS method. A rapid degradation of CS accompanied by an increase in CS antimicrobial activity by comparison with non-degraded CS (P<0.0001) was observed in SGF. Additionally, CS levels were not quantifiable in systemic circulation using a highly sensitive method and concurrent oral challenge did not affect CS absorption in an induction model of subclinical post-weaning diarrhea (PWD).

Keywords: Antimicrobial activity; Colistin sulfate; E. coli; Gastric stability; Intestinal absorption; Pigs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacokinetics
  • Anti-Bacterial Agents / therapeutic use*
  • Biological Availability
  • Colistin / pharmacokinetics
  • Colistin / therapeutic use*
  • Diarrhea / microbiology
  • Diarrhea / veterinary
  • Enterotoxigenic Escherichia coli / drug effects*
  • Escherichia coli Infections / drug therapy
  • Escherichia coli Infections / microbiology
  • Escherichia coli Infections / veterinary*
  • Swine
  • Swine Diseases / drug therapy
  • Swine Diseases / microbiology*
  • Tandem Mass Spectrometry

Substances

  • Anti-Bacterial Agents
  • Colistin