Glutathione S-transferase-dependent conjugation of leukotriene a4-methyl ester to leukotriene C4-methyl ester in mammalian skin

Rajesh Agarwal, Haider Raza, David L. Allyn, David R. Bickers, Hasan Mukhtar

Research output: Contribution to journalArticlepeer-review

12 Citations (Scopus)

Abstract

The glutathione S-transferase (GST)-dependent conjugation of reduced glutathione (GSH) with leukotriene A4 (LTA4)-methyl ester in rodent and human skin was investigated. Incubation of [3H]LTA4-methyl ester (1 nmole, ≈200,000 dpm) with cytosol prepared from rat, mouse and human skin or with affinity purified GST from rat skin cytosol in the presence of GSH resulted in the formation of LTC4-methyl ester. Maximum enzyme activity was observed in rat skin followed by mouse and human skin. With heat-denatured cytosol or in the absence of GSH, the product formation was negligible. GST purified from rat skin cytosol by GSH-agarose affinity chromatography exhibited a several-fold increase in the specific activity of enzyme with 1-chloro-2,4-dinitrobenzene (55-fold), ethacrynic acid (67-fold) and LTA4-methyl ester (12-fold) as substrates. Western blot analysis of the affinity purified GST indicated a predominant expression of the Pi class of GST isozyme followed by Mu and Alpha classes of isozymes. The formation of LTC4-methyl ester was established by its radioactivity profile on high pressure liquid chromatography and absorption spectroscopy. These results suggest that, in addition to xenobiotic metabolism, cutaneous GSTs may also be capable of metabolizing physiological substrates such as LTA4.

Original languageEnglish
Pages (from-to)2047-2053
Number of pages7
JournalBiochemical Pharmacology
Volume44
Issue number10
DOIs
Publication statusPublished - Nov 17 1992
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Pharmacology

Fingerprint

Dive into the research topics of 'Glutathione S-transferase-dependent conjugation of leukotriene a4-methyl ester to leukotriene C4-methyl ester in mammalian skin'. Together they form a unique fingerprint.

Cite this