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Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
Study on the nitric oxide generating effects from aristolochic acid in vitro
1Institute of Nature Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan. saibo421@sina.com
European Journal of Mass Spectrometry (Chichester, England)
|August 30, 2008
Summary
Aristolochic acid (AA) can generate nitric oxide (NO) when metabolized by intestinal bacteria. This NO generation may contribute to the toxicity of aristolochic acid (AA).
Area of Science:
- Biochemistry
- Microbiology
- Toxicology
Background:
- Aristolochic acid (AA) is a nephrotoxic and carcinogenic compound.
- The precise mechanisms underlying AA toxicity are not fully understood.
Purpose of the Study:
- To investigate the nitric oxide (NO)-generating effects of aristolochic acid (AA) in vitro.
- To explore the role of intestinal bacteria in AA metabolism and NO production.
Main Methods:
- An in vitro nitric oxide (NO) assay system based on the Griess reaction was employed.
- Aristolochic acid I (AAI) and aristolochic acid II (AAII) were separated using preparative HPLC.
- Incubation of AAI and AAII with human intestine bacteria (HIB) and rat intestine bacteria (RIB).
- Detection of denitroso metabolites using liquid chromatography/tandem mass spectrometry (LC-MS/MS).
Main Results:
- Nitric oxide (NO) was generated from AAI and AAII upon incubation with intestinal bacteria (HIB and RIB).
- Denitroso metabolites of AAI and AAII were identified in vitro.
- A correlation between AA metabolism by intestinal bacteria and NO generation was observed.
Conclusions:
- Intestinal bacteria metabolize aristolochic acid (AA) to produce nitric oxide (NO).
- This NO generation is a potential mechanism contributing to the toxicity of aristolochic acid (AA).
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