Fishing out the proteomic changes in salmon exposed to drugs
November 21, 2014 § Leave a comment
Pharmaceutical compounds in waterways have become a growing environmental concern. Researchers want to know how the human and veterinary drugs affect fish and other aquatic animals as well as how these drug-bearing animals affect the food chain on which we rely.
In a paper just out in the journal Molecular & Cellular Proteomics, investigators analyzed how three common human drugs affect Atlantic salmon. They chose to study Atlantic salmon because wild stocks of the fish are dwindling. Water quality is thought to be one cause of the decline.
The investigators studied the pain-killer acetaminophen, the hypertension drug atenolol, and epilepsy and antidepression drug carbamazepine. These drugs represent different classes of pharmaceuticals.
By carrying out proteomics based on mass spectrometry, the investigators found that exposure to environmentally relevant concentrations of the three drugs changed the protein-expression profile in the livers of the salmon.
In particular, the investigators observed that levels of enzymes involved in energy metabolism, such as mitochondrial ATP synthase, acetyl-CoA acetyltransferase, and glyceraldehydes-3-phosphate dehydrogenase, changed. The first author on the paper, Miriam Hampel at the Andalusian Centre for Marine Science and Technology in Spain, says that it was surprising to see changes in protein-expression levels in the fish even in the presence of low concentrations of the drugs.
Hampel and colleagues now want to see how molecular mechanisms in which these enzymes are involved are affected. As Hampel explains, the most important step will be “to link these and similar findings with physiological effects in exposed organisms that could indicate long-term ecological effects.”
The ecological effects are not just limited to the Atlantic salmon, notes Hampel. “Humans are also more and more exposed to these compounds through drinking water,” she says.