Influence of mercury and selenium chemistries on the progression of cardiomyopathy in pygmy sperm whales, Kogia breviceps.
More than half of pygmy sperm whales (Kogia breviceps) that strand exhibit signs of cardiomyopathy (CMP). Many factors may contribute to the development of idiopathic CMP in K. breviceps, including genetics, infectious agents, contaminants, biotoxins, and dietary intake (e.g. selenium, mercury, and pro-oxidants). This study assessed trace elements in K. breviceps at various stages of CMP progression using fresh frozen liver and heart samples collected from individuals that stranded along US Atlantic and Gulf coasts between 1993 and 2007. Standard addition calibration and collision cell inductively coupled plasma mass spectrometry (ICP-MS) were employed for total Se analysis and pyrolysis atomic absorption (AA) was utilized for total Hg analysis to examine if the Se/Hg detoxification pathway inhibits the bioavailability of Se. Double spike speciated isotope dilution gas chromatography ICP-MS was utilized to measure methyl Hg and inorganic Hg. Immunoblot detection and colorimetric assays were used to assess protein oxidation status. Data collected on trace elements, selenoproteins, and oxidative status were evaluated in the context of animal life history and other complementary histological information to gain insight into the biochemical pathways contributing to the development of CMP in K. breviceps. Cardiomyopathy was only observed in adult pygmy sperm whales, predominantly in male animals. Both Hg:Se molar ratios and overall protein oxidation were greater in males than females and increased with progression of CMP.
Analytical Chemistry Division, National Institute of Standards and Technology, Hollings Marine Laboratory, Charleston, SC 29412, USA. colleen.bryan@nist.gov
Colleen E
CE
Bryan
W Clay
WC
Davis
Wayne E
WE
McFee
Carola A
CA
Neumann
Jennifer
J
Schulte
Gregory D
GD
Bossart
Steven J
SJ
Christopher
D000375:Aging / Q000378:metabolism; D000818:Animals; D001682:Biological Availability; D009202:Cardiomyopathies / Q000378:metabolism* / Q000473:pathology; D018450:Disease Progression; D004785:Environmental Pollutants / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics / Q000633:toxicity; D005260:Female; D006321:Heart / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008628:Mercury / Q000737:chemistry / Q000378:metabolism* / Q000493:pharmacokinetics / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects; D012643:Selenium / Q000737:chemistry / Q000378:metabolism* / Q000493:pharmacokinetics / Q000633:toxicity*; D012727:Sex Characteristics; D014907:Whales / Q000378:metabolism*
D004785:Environmental Pollutants; D008628:Mercury; D012643:Selenium