Nandrolone androgenic hormone presents genotoxic effects in different cells of mice

Nandrolone is an androgenicanabolic steroid (AAS) with diverse medical applications but taken indiscriminately by some to rapidly increase muscle mass. The aim of this study was to evaluate the genotoxic and clastogenic potential of nandrolone (deca-durabolin (R)) in vivo in different cells of mice, using the comet assay and micronucleus test, respectively. The animals received subcutaneous injection of the three doses of the steroid (1.0, 2.5 and 5.0?mg kg-1 body weight). Cytotoxicity was assessed by scoring 200 consecutive total polychromatic (PCE) and normochromatic (NCE) erythrocytes (PCENCE ratio). The results showed a significant dose-related increase in the frequency of DNA damage in leukocytes, liver, bone marrow, brain and testicle cells at the three tested doses and a significant increase of the micronucleated polychromatic erythrocytes at all tested doses. Under our experimental conditions, the nandrolone steroid hormone showed genotoxic and clastogenic effects when administered subcutaneously to mice. Copyright (c) 2011 John Wiley & Sons, Ltd.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Evaluation of the genotoxic and antigenotoxic potential of Brassica oleracea L. var. acephala D.C. in different cells of mice

Ethnopharmacological relevance: Brassica oleracea L var. acephala D.C. has been extensively used in Brazilian traditional medicine to treat gastric ulcer.Aim of the study: This study was conducted to evaluate the in vivo genotoxic and/or antigenotoxic potential of a Brassica oleraceae hydroalcoholic extract obtained from the leaves, in different cells of mice.Materials and methods: Analyses were performed using the comet assay, on leukocytes (collected 4 and 24 h after treatment), liver, brain, bone marrow and testicular cells (collected 24 h after treatment), and using the micronucleus test (MN) in bone marrow cells. Eight groups of albino Swiss mice were treated (N=6): control (C), positive control (doxorubicin 80 mg/kg (DXR)), and six experimental groups, which received 500, 1000 and 2000 mg/kg of Brassica oleraceae extract alone by gavage, while a further three groups received the same doses plus DXR (80 mg/kg). We calculated the damage scores, and their averages were compared by ANOVA followed by the Tukey test for multiple comparisons.Results: The results demonstrated that none of the tested doses of Brassica oleraceae extract showed genotoxic effects by the comet assay, or clastogenic effects by the MN test. on the other hand, for all cells evaluated, the three tested doses of the Brassica extract promoted inhibition of DNA damage induced by DXR.Conclusions: Under our experimental conditions, Brassica oleraceae leaf extract showed no genotoxic or clastogenic effects in different cells of mice. However, it did show a significant decrease in DNA damage induced by doxorubicin. It is suggested that the antigenotoxic properties of this extract may be of great pharmacological importance, and may be beneficial for cancer prevention. (C) 2012 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

First cytogenetic characterization of the giant Amazonian catfish Brachyplatystoma filamentosum (Siluriformes, Pimelodidae)

In contrast to the enormous variability of Neotropical fish species, genetic information about many groups is not yet available. Chromosomal studies have greatly contributed to the characterization of several species, providing important data on these animals. We performed the first cytogenetic characterization of the Amazonian fish species Brachyplatystoma filamentosum (Pimelodidae), popularly known as "piraiba". The results revealed a diploid number of 2n = 56 composed of 24 metacentric, 12 submetacentric, and 10 acrocentric chromosomes in both females and males. After silver nitrate treatment (AgNORs) it was possible to visualize the nucleolus organizer region located in the terminal portion of the short arms of subtelocentric chromosome pair 22, presenting size polymorphism. Hybridization with 18S and 5S rDNA probes confirmed the number and location of 18S marks rDNA in pair 22 and differences in the size of signals among homologs. The 5S rDNA genes were localized near the centromere on the short arms of chromosome pair 19. Constitutive heterochromatin (C-bands) were localized predominantly in the terminal regions of the chromosomes, and also occurred in some interstitial and centromeric positions. The chromosomal genetic data obtained in this study contribute to the biological characterization of B. filamentosum, which has economic and ecological importance as the largest freshwater catfish occurring in many rivers of the Amazon and Tocantins-Araguaia basins in Brazil. These results may also be used in to infer relationships among Pimelodidae species.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP