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Sulfurtransferases and cyanide detoxification in mouse liver, kidney, and brain

M Wróbel1, H Jurkowska, L Sliwa

  • 1Institute of Medical Biochemistry, Department of Biology, Collegium Medicum UJ, 31-034 Kraków, ul. Kopernika 7, Poland. mbwrobel@cyf-kr.edu.pl

Toxicology Mechanisms and Methods
|December 22, 2009
PubMed

Insights

This study reveals how mouse organs process cyanide. The liver showed impaired detoxification, while the kidney and rhombencephalon brain region utilized sulfurtransferases like rhodanese and cystathionase for defense against cyanide poisoning.

Area of Science:

  • Biochemistry
  • Toxicology
  • Metabolism

Background:

  • Cyanide is a potent toxin that requires detoxification pathways.
  • Sulfurtransferases play a role in sulfur metabolism and detoxification.
  • Understanding organ-specific responses to cyanide is crucial for developing treatments.

Purpose of the Study:

  • To investigate the activity of rhodanese, 3-mercaptopyruvate sulfurtransferase (MPST), and cystathionase in response to cyanide exposure.
  • To assess sulfane sulfur and total sulfur content in various mouse tissues after cyanide administration.
  • To elucidate the role of these enzymes and sulfur compounds in cyanide detoxification across different organs.

Main Methods:

  • Mice were administered a sublethal dose of cyanide (4 mg/kg body weight) intraperitoneally.
  • Enzyme activities (rhodanese, MPST, cystathionase) were measured in liver, kidney, and four brain regions (tele-, meso-, di-, rhombencephalon) at 30 min and 2 h post-injection.
  • Sulfane sulfur and total sulfur content were analyzed in the same tissues.

Main Results:

  • Liver: Cyanide impaired MPST activity and inhibited rhodanese, suggesting compromised detoxification.
  • Kidney: Rhodanese activity increased significantly, and cystathionase activity elevated, indicating their involvement in cyanide detoxification.
  • Rhombencephalon: Increased activity of MPST, cystathionase, and rhodanese, along with stable sulfur levels, suggests a robust defense system. Telencephalon showed increased total sulfur but not sulfane sulfur, possibly involving GSH or cysteine.

Conclusions:

  • Cyanide detoxification mechanisms vary significantly between mouse organs.
  • The kidney and rhombencephalon exhibit active sulfurtransferase-mediated defense against cyanide.
  • The liver's detoxification process appears to be impaired by this cyanide dose, while other brain regions may utilize different sulfur-containing compounds for defense.

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