Involvement of Cd Bioaccumulation in Spinal Deformities Occurrence in Natural Populations of Mediterranean Killifish

UR 09/30: Génétique, Biodiversité et Valorisation des Bioressources, Institut de Biotechnologie, Université de Monastir, Monastir, Tunisia.
Biological trace element research (Impact Factor: 1.75). 10/2008; 128(1):72-81. DOI: 10.1007/s12011-008-8255-z
Source: PubMed


The aim of this study was to investigate the possible influence of environmental exposure to cadmium (Cd) on the spinal deformities occurrence in the Mediterranean killifish, Aphanius fasciatus (Pisces: Cyprinodontidae). For this purpose, some indicators of skeletal bone mineralization, Cd, and calcium (Ca) concentrations in spinal column as well as bioaccumulation of Cd from the water and the sediment have been compared in normal and deformed fish collected from polluted (S1) and nonpolluted (S2) areas in the Gulf of Gabès in Tunisia. When compared to the normal fish, the deformed fish showed signs of spinal column demineralization such as significant decrease in the ash weight/dry weight ratio, percentage of nonorganic components content, and Ca concentration. Cd concentrations in spinal column and liver were significantly higher in deformed fish than in normal fish. A highly significant negative correlation (r = -0.915, p < 0.01) between Cd and Ca concentrations was noted in spinal column of deformed fish. Bioaccumulation factors of Cd in the liver from the water and the sediment in deformed fish were also significantly higher (p < 0.0001) than in normal fish from S1 and S2. These findings suggest that the ability to accumulate large amount of Cd may represent a potential risk to induce spinal deformities in natural populations of Mediterranean killifish.

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Available from: Imed Messaoudi, Sep 16, 2014
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    • "In aquatic animals, Cd exposure has been shown to change plasma stress parameters (i.e 62 cortisol, glucose) (Garcia-Santos et al., 2011, Lin et al., 2011 and Pratap and Wendelaar Bonga, 63 1990), interfere in ion regulation (Firat and Kargin, 2010, McGeer et al., 2000 and Pratap et al., 64 1989), inhibit enzyme activities (Lionetto et al., 2000 and Sastry and Subhadra, 1985), and cause 65 skeletal deformities and calcium (Ca) balance disturbances (Kessabi et al., 2009 and Muramoto, 66 1981). In fact, Cd exposure has been associated with disruption of important ions like "
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    • "While, skeletal malformations in aquaculture appear to be related to a complex interaction of genetic, procedural and infectious/immunological factors (Lall and Lewis-McCrea, 2007; Aunsmo et al., 2008, 2009; Bardon et al., 2009), the presence of deformities in natural populations are most likely related to pollution (Lemly, 2002; Kessabi et al., 2009; Messaoudi et al., 2009a). Indeed, it has been suggested that spinal deformities in natural populations of fish serve as a biomarkers of environmental pollution (De La Cruz-Aguero and Perezgomez-Alvarez, 2001; Antunes and Lopes Da Cunha, 2002; Xuan Yang, 2004). "
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    • "For instance, skeletal deformities in European smelts (Osmerus eperlanus) from the Elbe Estuary in Germany have been attributed to high concentrations of this element in the liver (Pohl 1990). Moreover, recent studies reported an association between spinal deformities and the bioaccumulation of some metals like Cd 2? and Zn in natural populations of the grass goby (Zosterisessor ophiocephalus) and Mediterranean killifish (Aphanius fasciatus) collected from the Gulf of Gabes in Tunisia (Kessabi et al. 2009; Messaoudi et al. 2009). Laboratory studies performed by Cheng et al. (2000) and Sassi et al. (2010) established a correlation between Cd 2? contamination and the occurrence of skeletal deformities at early stages of fish development (embryos and juveniles). "
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