Linked Life Data

20169435

Source:http://linkedlifedata.com/resource/pubmed/id/20169435

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2010-12-24
pubmed:abstractText
Methylmercury (MeHg) and polychlorinated biphenyls (PCBs) are widespread environmental pollutants commonly found as contaminants in the same food sources. Even though their neurotoxic effects are established, the mechanisms of action are not fully understood. In the present study, we have used the mouse hippocampal neuronal cell line HT22 to investigate the mechanisms of neuronal death induced by MeHg, PCB 153, and PCB 126, alone or in combination. All chemicals induced cell death with morphological changes compatible with either apoptosis or necrosis. Mitochondrial functions were impaired as shown by the significant decrease in mitochondrial Ca²+ uptake capacity and ATP levels. MeHg, but not the PCBs, induced loss of mitochondrial membrane potential and release of cytochrome c into the cytosol. Also, pre-treatment with the antioxidant MnTBAP was protective only against cell death induced by MeHg. While caspase activation was absent, the Ca²+-dependent proteases calpains were activated after exposure to MeHg or the selected PCBs. Furthermore, lysosomal disruption was observed in the exposed cells. Accordingly, pre-treatment with the calpain specific inhibitor PD150606 and/or the cathepsin D inhibitor Pepstatin protected against the cytotoxicity of MeHg and PCBs, and the protection was significantly enhanced when the two inhibitors were combined. Simultaneous exposures to lower doses of MeHg and PCBs suggested mostly antagonistic interactions. Taken together, these data indicate that MeHg and PCBs induce caspase-independent cell death via parallel activation of calpains and lysosomal proteases, and that in this model oxidative stress does not play a major role in PCB toxicity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1476-3524
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
19
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
183-94
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Hippocampal neurons exposed to the environmental contaminants methylmercury and polychlorinated biphenyls undergo cell death via parallel activation of calpains and lysosomal proteases.
pubmed:affiliation
Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden. Roshan.Tofighi@ki.se
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't