Oxalate deposition on asbestos bodies.

Published

Journal Article

We report on a deposition of oxalate crystals on ferruginous bodies after occupational exposure to asbestos demonstrated in 3 patients. We investigated the mechanism and possible significance of this deposition by testing the hypothesis that oxalate generated through nonenzymatic oxidation of ascorbate by asbestos-associated iron accounts for the deposition of the crystal on a ferruginous body. Crocidolite asbestos (1000 microg/mL) was incubated with 500 micromol H(2)O(2) and 500 micromol ascorbate for 24 hours at 22 degrees C. The dependence of oxalate generation on iron-catalyzed oxidant production was tested with the both the metal chelator deferoxamine and the radical scavenger dimethylthiourea. Incubation of crocidolite, H(2)O(2), and ascorbate in vitro generated approximately 42 nmol of oxalate in 24 hours. Oxalate generation was diminished significantly by the inclusion of either deferoxamine or dimethylthiourea in the reaction mixture. Incubation of asbestos bodies and uncoated fibers isolated from human lung with 500 micromol H(2)O(2) and 500 micromol ascorbate for 24 hours at 22 degrees C resulted in the generation of numerous oxalate crystals. We conclude that iron-catalyzed production of oxalate from ascorbate can account for the deposition of this crystal on ferruginous bodies.

Full Text

Duke Authors

Cited Authors

  • Ghio, AJ; Roggli, VL; Richards, JH; Crissman, KM; Stonehuerner, JD; Piantadosi, CA

Published Date

  • August 2003

Published In

Volume / Issue

  • 34 / 8

Start / End Page

  • 737 - 742

PubMed ID

  • 14506632

Pubmed Central ID

  • 14506632

International Standard Serial Number (ISSN)

  • 0046-8177

Language

  • eng

Conference Location

  • United States