Distributional pattern of zinc, cadmium, mercury, and selenium in livers of Hooded Seal (Cystophora cristata)

Nielsen, Christian Overgaard; Dietz, Runé

doi:10.1007/bf02789141

Cited by 86 publications

(7 citation statements)

References 2 publications

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“…Moreover, many studies have reported Hg and Se to be correlated in a molar ratio of 1:1, as in HgSe (e.g. Koeman et al 1973, Nielsen & Dietz 1990, Wagemann et al 1998. The molar ratio of Hg:Se in the liver of grey seals from the Faroe Islands was ~1 (Fig.…”

Section: Toxicological Aspectsmentioning

confidence: 96%

Trace element bioaccumulation in grey seals Halichoerus grypus from the Faroe Islands

Bustamante¹,

Morales²,

Mikkelsen³

et al. 2004

Mar. Ecol. Prog. Ser.

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Grey seals Halichoerus grypus were sampled in the Faroe Islands archipelago during the summers of 1993 to 1995. Concentrations of Cd, Cu, Hg, Se and Zn were measured in the liver, kidney and muscle of 68 seals. All elements except Zn exhibited lowest concentrations in the muscle. The liver contained the highest concentrations of Cu, Hg, Se and Zn, while the kidney contained the highest Cd concentrations. However, trace element concentrations within the tissues were influenced by sex and age. Thus, females had clearly higher Cd concentrations than males. Age was the most important factor influencing the concentration of Cd, Hg and Se in the liver, and of Cd and Hg in the kidney. A strong positive correlation between Cd, Hg and Zn in the kidney suggests the presence of a detoxification process involving metallothionein proteins. Similarly, a strong positive correlation between Hg and Se and a molecular Hg:Se ratio close to 1 in the liver suggests a demethylation process leading to the formation of mercuric selenide granules. High Hg concentrations could be related to fish consumption by the grey seal, but a piscivorous diet could not be responsible for the very high Cd concentrations. This suggests that the seals' diet changes during the year, and may include a significant proportion of cephalopods in seasons other than summer. Finally very high Cd concentrations in grey seal tissues compared to other grey seal populations also suggest that the Faroe Islands are subject to sub-arctic influences.

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Section: Toxicological Aspectsmentioning

confidence: 96%

Trace element bioaccumulation in grey seals Halichoerus grypus from the Faroe Islands

Bustamante¹,

Morales²,

Mikkelsen³

et al. 2004

Mar. Ecol. Prog. Ser.

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“…HgSe granules (tiemannite) have been identified in the liver of seabirds, marine mammals and humans (Martoja & Berry 1980, Pelletier 1985, Hansen et al 1989, Nigro & Leonzio 1996. Moreover, many studies also reported that Hg and Se are correlated in a 1:1 molar ratio as in HgSe (Koeman et al 1973, Nielsen & Dietz 1990, Law et al 1997, Wagemann et al 1998. G. macrorhynchus and K. breviceps from New Caledonia had a Hg:Se molar ratio close to 1 and a low percentage of organic Hg in liver (Fig.…”

Section: Detoxification Processesmentioning

confidence: 98%

Trace elements in two odontocete species (Kogia breviceps and Globicephala macrorhynchus) stranded in New Caledonia (South Pacific)

Bustamante

Garrigue²,

Breau

et al. 2003

Environmental Pollution

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Liver, muscle and blubber tissues of two short-finned pilot whales (Globicephala macrorhynchus) and two pygmy sperm whales(Kogia breviceps) stranded on the coast of New Caledonia have been analysed for 12 trace elements (Al, Cd, Co, Cr, Cu. Fe, organic and total Hg, Mn, Ni, Se, V, and Zn). Liver was shown to be the most important accumulating organ for Cd, Cu, Fe, Hg, Se, and Zn in both species, G. macrorhynchus having the highest Cd, Hg, Se and Zn levels. In this species, concentrations of total Hg are particularly elevated, reaching up to 1452 microg g(-1) dry wt. Only a very low percentage of the total Hg was organic. In both species,the levels of Hg are directly related to Se in liver. Thus, a molar ratio of Hg:Se close to 1.0 was found for all specimens, except for the youngest K. breviceps. Our results suggest that G. macrorhynchus have a physiology promoting the accumulation of high levels of naturally occurring toxic elements. Furthermore, concentrations of Ni, Cr and Co are close to or below the detection limit in the liver and muscles of all specimens. This suggests that mining activity in New Caledonia, which typically elevates the levels of these contaminants in the marine environment, does not seem to be a significant source of contamination for these pelagic marine mammals.

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“…As a result, the pH of the intestine reduces. In acidic pH, inorganic calcium [27,28,29], magnesium [29], iron [27], manganese [36], magnesium [37], boron [38], and copper and zinc [39] salts become soluble. This process promotes the colonic absorption of inorganic minerals to the gut.…”

Section: Osteoporosismentioning

confidence: 99%

Biological Activities of Lactose-Based Prebiotics and Symbiosis with Probiotics on Controlling Osteoporosis, Blood-Lipid and Glucose Levels

et al. 2018

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Lactose-based prebiotics are synthesized by enzymatic- or microbial- biotransformation of lactose and have unique functional values. In this comprehensive review article, the biochemical mechanisms of controlling osteoporosis, blood-lipid, and glucose levels by lactose-based prebiotics and symbiosis with probiotics are reported along with the results of clinical investigations. Interaction between lactose-based prebiotics and probiotics reduces osteoporosis by (a) transforming insoluble inorganic salts to soluble and increasing their absorption to gut wall; (b) maintaining and protecting mineral absorption surface in the intestine; (c) increasing the expression of calcium-binding proteins in the gut wall; (d) remodeling osteoclasts and osteoblasts formation; (e) releasing bone modulating factors; and (f) degrading mineral complexing phytic acid. Lactose-based prebiotics with probiotics control lipid level in the bloodstream and tissue by (a) suppressing the expressions of lipogenic- genes and enzymes; (b) oxidizing fatty acids in muscle, liver, and adipose tissue; (c) binding cholesterol with cell membrane of probiotics and subsequent assimilation by probiotics; (d) enzymatic-transformations of bile acids; and (e) converting cholesterol to coprostanol and its defecation. Symbiosis of lactose-based prebiotics with probiotics affect plasma glucose level by (a) increasing the synthesis of gut hormones plasma peptide-YY, glucagon-like peptide-1 and glucagon-like peptide-2 from entero-endocrine L-cells; (b) altering glucose assimilation and metabolism; (c) suppressing systematic inflammation; (d) reducing oxidative stress; and (e) producing amino acids. Clinical investigations show that lactose-based prebiotic galacto-oligosaccharide improves mineral absorption and reduces hyperlipidemia. Another lactose-based prebiotic, lactulose, improves mineral absorption, and reduces hyperlipidemia and hyperglycemia. It is expected that this review article will be of benefit to food technologists and medical practitioners.

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Distributional pattern of zinc, cadmium, mercury, and selenium in livers of Hooded Seal (Cystophora cristata)

Cited by 86 publications

References 2 publications

Trace element bioaccumulation in grey seals Halichoerus grypus from the Faroe Islands

Trace element bioaccumulation in grey seals Halichoerus grypus from the Faroe Islands

Trace elements in two odontocete species (Kogia breviceps and Globicephala macrorhynchus) stranded in New Caledonia (South Pacific)

Biological Activities of Lactose-Based Prebiotics and Symbiosis with Probiotics on Controlling Osteoporosis, Blood-Lipid and Glucose Levels

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