Amphibians as Model Organisms for Study Environmental Genotoxicity

Abstract

Abstract. Animals, the silent sentinels, stand watch over the world's environmental health. Everyday, animals demonstrate intricate connections between them, us and our surroundings. Amphibians are vertebrates and include approximately 4400 existing species. Amphibians are in most cases, small, diverse and sensitive to environmental variability. They can be good indicators of habitat diversity, biological variety and local stressors on the environment. They are bathed in both water and air. They live outdoors on land and water and their skin, larvae and unshelled eggs are constantly exposed and in contact with the substances in their surroundings. We searched Web of Science and references of relevant publications to evidence the application of amphibians, especially Xenopus laevis as model animal in ecotoxicology.

Toxic and genotoxic effects of the imazethapyr-based herbicide formulation Pivot H® on montevideo tree frog Hypsiboas pulchellus tadpoles (Anura, Hylidae)

“…The SCGE test has become extensively valuable as a biomarker in amphibians to monitor contaminated areas (in situ assay) (Burlibasa and Gavrila, 2011;Maselli et al, 2010), as well as for the screening of xenobiotics after direct or indirect exposure (in vivo assay) (Mouchet et al, 2007;Nikoloff et al, 2014b;Pérez-Iglesias et al, 2014;Ruiz de Arcaute et al, 2014). We observed that, regardless of the length of treatment, IMZT acute exposure within the 0.39-1.17 mg/L concentration range increased the frequency of primary DNA lesions estimated by alkaline SCGE, a result opposite that of the MN test.…”

Detecting genomic damages in the frog Dendropsophus minutus: preserved versus perturbed areas

“…The results for genotoxicity obtained in this study are in agreement with Gonçalves et al (2013), using four species of toads sampled in natural and degraded areas, including D. minutus. Previous studies showed that amphibians, especially tadpoles, are one of the most sensitive vertebrate groups to evaluate the genotoxic effects of pesticides (Govindarajulu 2008;Burlibasa and Gavrila 2011).…”

“…These features make them excellent bioindicators of environmental quality (Ralph and Petras 1997;Gauthier et al 2003;Frenzilli et al 2009;Yin et al 2009;Burlibasa and Gavrila 2011;Valencia et al 2011;Gonçalves et al 2013).…”

Amphibian sperm DNA fragmentation

“…Given their unique anatomy, amphibians are particularly sensitive to fluctuations in environmental conditions; their exposed and permeable skin coupled with a dependence on water for breeding means that they often react adversely to changes in the environment before higher-order vertebrates (Burlibasa and Gavrila 2011). Additionally, the potential for a high rate of mutagenic change or impaired spermatogenesis in the testes means that amphibian sperm chromatin structural integrity (including sperm chromatin quality) could be a useful index of environmental toxicity on the reproductive system; this study has provided the technical basis and protocols by which the integrity of amphibian sperm chromatin might be evaluated as such an index.…”

“…The unique anatomy and physiology of amphibians leaves them particularly sensitive to fluctuations in environmental conditions. Their highly porous skin coupled with a dependence on water for breeding means they often react adversely to changes in the environment before that of higher order vertebrates Burlibasa and Gavrila 2011). Accordingly, amphibians have been described as a sentinel species for modelling the effects of climate change and environmental damage (Kloas and Lutz 2006;Burlibasa and Gavrila 2011;Valencia et al 2011).…”