Skip Navigation
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Your Environment. Your Health.

Publication Detail

Title: Organochalcogens inhibit mitochondrial complexes I and II in rat brain: possible implications for neurotoxicity.

Authors: Puntel, Robson Luiz; Roos, Daniel Henrique; Seeger, Rodrigo Lopes; Aschner, Michael; Rocha, João Batista Teixeira

Published In Neurotox Res, (2013 Aug)

Abstract: Organochalcogens, such as organoselenium and organotellurium compounds, can be neurotoxic to rodents. Since mitochondrial dysfunction plays a pivotal role in neurological disorders, the present study was designed to test the hypothesis that rat brain mitochondrial complexes (I, II, I-III, II-III and IV) could be molecular targets of organochalcogens. The results show that organochalcogens caused statistically significant inhibition of mitochondrial complex I activity, which was prevented by preincubation with NADH and fully blunted by reduced glutathione (GSH). Mitochondrial complex II activity remained unchanged in response to (PhSe)₂ treatment. Ebs and (PhTe)₂ caused a significant concentration-dependent inhibition of complex II that was also blunted by GSH. Mitochondrial complex IV activity was not modified by organochalcogens. Collectively, Ebs, (PhSe)₂ and (PhTe)₂ were more effective inhibitors of brain mitochondrial complex I than of complex II, whereas they did not affect complex IV. These observations are consistent with organochalcogens inducing mitochondrial complex I and II inhibition via their thiol-oxidase-like activity, with Ebs, (PhSe)₂ and (PhTe)₂ effectively oxidising critical thiol groups of these complexes.

PubMed ID: 23224748 Exiting the NIEHS site

MeSH Terms: Animals; Brain/drug effects*; Brain/enzymology; Chalcogens/toxicity*; Electron Transport Complex I/antagonists & inhibitors*; Electron Transport Complex I/metabolism; Electron Transport Complex II/antagonists & inhibitors*; Electron Transport Complex II/metabolism; Male; Mitochondrial Membranes/drug effects*; Mitochondrial Membranes/enzymology; Organoselenium Compounds/toxicity*; Rats; Rats, Wistar

to Top