Detection of lipid peroxidation in lung and in bronchoalveolar lavage cells and fluid

Our plain-English summary of Detection of lipid peroxidation in lung and in bronchoalveolar lavage cells and fluid, by J.M. Petruska, S.H. Wong, F.W. Sunderman, et al (Free Radical Biology & Medicine, 1990).

The study

• Authors: J.M. Petruska, S.H. Wong, F.W. Sunderman, B.T. Mossman
• Journal: Free Radical Biology & Medicine
• Published: 1990;9(1):51-8
• Cited by: 33 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Inhalation of toxic materials such as asbestos, silica, 100% oxygen, ozone, or nitrogen dioxide may lead to an increased production of reactive oxygen metabolites which may initiate lipid peroxidation. Measurement of lipid peroxidation in cells and fluid obtained by bronchoalveolar lavage (BAL), as well as in lung tissue, may aid in monitoring the development and extent of pulmonary damage after inhalation of a toxic substance. In this study, we employed a sensitive assay for detection of malondialdehyde (MDA), a breakdown product of lipid peroxidation. By separation of the adduct with thiobarbituric acid, using a reverse phase high pressure liquid chromatographic technique, we accurately and sensitively measured the content of MDA in BAL cells, lavage fluid, and lavaged lung tissue homogenates of rats. The amounts of sample required for detection of MDA were small enough possibly to be applied to use with human specimens; in addition, recovery of added MDA was acceptable with all types of samples. Inclusion of a metal chelator in the preparation of samples appeared necessary to prevent metal-catalyzed propagation of lipid peroxidation during the assay. Overall, the method described here using samples from rats may be applicable to detecting lipid peroxidation in BAL samples from humans.

In plain English

This laboratory study described and tested a method for measuring malondialdehyde (MDA), a breakdown product of lipid peroxidation, chemical damage to fats in cells that may follow breathing in toxic materials. The authors adapted an existing high pressure liquid chromatography test to cells and fluid washed out of the lungs (bronchoalveolar lavage) and to lung tissue from young male Fischer 344 rats. The study evaluated the test itself and did not include an asbestos exposure experiment. The method detected MDA in all three sample types, and MDA rose in a straight line with sample amount. Recovery of known amounts of added MDA was 79 to 106%. Lavage fluid contained a second, unidentified substance that the method kept separate from MDA. Samples prepared without the metal-binding chemical EDTA showed higher MDA levels. The authors concluded that the method may be applicable to human lavage samples. In their discussion, they reported that a separate study of theirs found increased MDA in lavage cells and fluid of rats inhaling crocidolite asbestos, but not in rats exposed to titanium dioxide.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Laboratory methods study (animal tissue samples) adapting an existing HPLC test for MDA
• Who was studied: Eight- to nine-week-old male Fischer 344 rats. The total number of rats is not stated; four animals were used in the EDTA comparison.
• Exposure: This study evaluated the measurement method and did not include an asbestos exposure experiment. In the discussion, the authors describe a separate study of theirs, using this method, in which MDA increased in lavage cells and fluid of rats inhaling crocidolite asbestos. This is a cited observation from that other study, not a result of this experiment.
• Main results:
  • The MDA test signal increased in a straight line (significant linear regression, p less than 0.01) with sample amount. This held up to 1 × 10^5 lavage cells per injection, 7.5 microlitres of reconstituted lavage fluid per injection, and 470 micrograms of lung tissue per injection.
  • Recovery of known amounts of MDA added to pooled lavage cell samples, lavage fluid samples and lung tissue samples ranged from 79 to 106%.
  • The salt and buffer solutions used did not interfere with the test. Recovery of standard added to these solutions ranged from 96 to 106%.
  • Only lavage fluid samples showed an additional substance reacting with the test chemical (retention time 14.6 minutes, compared with 3.8 minutes for MDA). The authors had not identified it.
  • Lavage cells and lung tissue prepared in a solution containing EDTA gave lower MDA levels than those prepared in buffer without EDTA (p less than 0.01; 4 samples per group).
  • Repeat measurements of a human reference serum sample gave a coefficient of variance of 3.3%.
  • Not a result of this experiment: in the discussion, the authors report that in their separate study, exposure to titanium dioxide, a nonfibrous particulate, did not cause fibrosis or inflammation and did not raise MDA in lavage cells or fluid.
• The authors' conclusion: The authors concluded that the method, tested here on rat samples, may be applicable to detecting lipid peroxidation in lavage samples from humans. They also concluded that leaving EDTA out of sample preparation may lead to overestimates of lipid peroxidation.

Topics

Medical terms in this study, explained in our Lexicon: Bronchoalveolar Lavage (BAL).

Related studies

• Enhanced lipid peroxidation in lung lavage of rats after inhalation of asbestos — J.M. Petruska, K.O. Leslie, et al. (1991)
• Microsomal lipid peroxidation and oxy-radicals formation are induced by insoluble iron-containing minerals — M. Fontecave, M. Jaouen, et al. (1990)
• Brief inhalation of asbestos compromises superoxide production in cells from bronchoalveolar lavage — J.M. Petruska, J. Marsh, et al. (1990)
• Changes in surfactant in bronchoalveolar lavage fluid after hemithorax irradiation in patients with mesothelioma — M. Hallman, P. Maasilta, et al. (1990)
• Diagnostic value of asbestos bodies in bronchoalveolar lavage fluid — P. De Vuyst, P. Dumortier, et al. (1987)
• Two dimensional protein patterns of bronchoalveolar lavage fluid from non-smokers, smokers, and subjects exposed to asbestos — M. Lindahl, T. Ekström, et al. (1996)

Browse more research in Free Radical Biology & Medicine, or return to medical research.