NOAA scientists and their colleagues have discovered a biological marker in the blood of laboratory zebrafish and marine mammals that shows when they have been repeatedly exposed to low levels of domoic acid, which is potentially toxic at high levels.
While little is known about how low-level exposure to domoic acid affects marine animals or humans, high-level exposure through eating contaminated seafood can be toxic, and can lead to amnesic shellfish poisoning, with symptoms such as seizures, short-term memory loss and, in rare cases, death. Domoic acid is produced by particular species of marine algae and accumulates in marine animals such as clams and mussels.
The findings are reported in a study published in Public Library of Science journal (PLoS ONE), a peer-reviewed scientific journal. Up until now, the absence of a marker for such chronic exposure has been a barrier to accurately assessing possible effects to humans.
"This study paves the way for creating reliable blood tests for low-level domoic acid exposure, which could help scientists assess the effects of chronic exposure to both wildlife and people who eat seafood," said Kathi Lefebvre, Ph.D., a NOAA fisheries biologist and the lead author of the study. "We don't know yet if the same antibody response we found in the laboratory in zebrafish and naturally exposed California sea lions also occurs in humans. Our next step is to team up with human-health experts to answer that question."
In the NOAA study, scientists injected zebrafish two to four times a month over nine months with low levels of domoic acid in the laboratory. Although the zebrafish appeared healthy after 18 weeks, scientists detected an antibody response for domoic acid in blood samples. Scientists found a similar antibody response in blood samples taken from wild sea lions from central California, confirming that natural exposure to the toxin produces a similar response in marine mammals.
The researchers also found that long-term, low-level exposure to domoic acid does not build tolerance or resistance to it, but instead makes zebrafish more sensitive to the neurotoxin.
Domoic acid was first identified as a shellfish toxin in 1987, after more than 100 people were sickened from eating contaminated mussels harvested off the Canadian province of Prince Edward Island. In 1998, more than 400 California sea lions died on the U.S. west coast after consuming anchovies containing domoic acid.
Since the early 1990s, regular monitoring of shellfish has protected people from amnesic shellfish poisoning caused by high levels of domoic acid.
Lefebvre will continue to work with co-authors, John D. Hansen, Ph.D, an immunologist with the U.S. Geological Survey-Western Fisheries Research Center, Donald R. Smith, Ph.D., a toxicologist at the University of California at Santa Cruz, and David J. Marcinek, Ph.D., a physiologist at the University of Washington, to look for health consequences of low-level exposure to domoic acid using the antibody marker.
The study, "A Novel Antibody-Based Biomarker for Chronic Algal Toxin Exposure and Sub-Acute Neurotoxicity," was conducted by scientists with NOAA, the Marine Mammal Center, the U.S. Geological Survey-Western Fisheries Research Center, the University of Washington and the University of California Santa Cruz, and is available at http://dx.plos.org/10.1371/journal.pone.0036213 Funding for the study was provided by NOAA's Ecology and Oceanography of Harmful Algal Blooms program.
Brian Gorman | EurekAlert!
A better way to measure the stiffness of cancer cells
01.03.2017 | Duke University
Humans have three times more brown body fat
01.03.2017 | Technische Universität München
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.
On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
01.03.2017 | Health and Medicine
01.03.2017 | Physics and Astronomy
01.03.2017 | Life Sciences