Induction of micronucleated cells in the shed skin of salamanders (Ambystoma sp.) treated with colchicine or cyclophosphamide

Abstract

The micronucleus (MN) assay can be used to detect the genotoxic effects of chemical agents in virtually any cell that divides frequently. Salamanders (Ambystoma sp.) are amphibians that can be easily maintained and bred in the laboratory and spontaneously shed their skin every 2.5-4 days. In this present study, we have evaluated the usefulness of this shed skin for the MN assay. We exposed salamanders to different concentrations of both the aneugen colchicine (COL) and the clastogen cyclophosphamide (CP) and we determined the frequency of micronucleated cells (MNCs) in their sheds. Fragments of shed skin were placed on clean slides, fixed, stained, observed with a light microscope, and the number of MNCs was counted. The MNC frequency was increased significantly by all doses of COL and CP tested, administered either as single or repeated exposures. The presence of MNCs in the shed skin and the speed of sloughing lead us to propose that the sheds of Ambystoma sp., or other amphibians that slough their skin, are suitable alternative models for detecting genotoxic exposures relevant to aquatic environments.

Micronucleus test on Triturus carnifex as a tool for environmental biomonitoring

“…This study is the first to report the frequencies of micronucleated erythrocytes in postmetamorphic adults salamanders as the micronucleus test has been so far performed on blood samples from larvae only [Siboulet et al, ]. The frequencies of micronucleated erythrocytes in peripheral blood detected in the present work are comparable to those assessed in anurans [Marques et al, ; Bosch et al, ] while the frequencies of micronucleated cells observed in shed skins samples are similar to those observed by Zamora‐Perez et al [] in the axolotl (Caudata: Ambystoma ). These findings seem to suggest that background MN frequencies may be comparable among amphibian species.…”

Micronucleated erythrocyte frequencies in old and new world primates: Measurement of micronucleated erythrocyte frequencies in peripheral blood ofCallithrix jacchus as a model for evaluating genotoxicity in primates

“…A highly proliferating tissue like blood is required to carry out this assay [Lähdetie, 1983;Shuilin and Baker, 1989;Schmezer et al, 1990;Torres-Bugarín et al, 1998;Zamora-Perez et al, 2004], and only a drop of blood is needed to measure micronucleus (MN) frequencies in peripheral blood, so that it is not necessary to kill the animal [Zúñiga-González et al, 1998;Zúñiga-González et al, 2001b]. In some species, spontaneous MNEs can be observed in peripheral blood [Zúñiga et al, 1996a;Zúñiga et al, 2000;Zúñiga-González et al, 2001a], because the reticuloendothelial system inefficiently removes them from the circulation.…”

Increased micronuclei and nuclear abnormalities in buccal mucosa and oxidative damage in saliva from patients with chronic and aggressive periodontal diseases

“…MN originate from chromosome fragments or whole chromosomes that lag behind in anaphase during nuclear division . The evaluation of MN detects both clastogenic and aneugenic events . The presence of MN is an indicator of the effect of mutagenic or genotoxic agents, especially micronucleogenic compounds .…”