Avaliação dos efeitos citogenotóxicos da diamina cadaverina, presente no necrochorume, por meio de ensaios com sistemas testes in vitro e in vivo

• Ano de defesa: 2016
• Autor(a) principal: Hara, Raquel Vaz [UNESP]
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Allium cepa; Cultura de células; Ratos Wistar; Citotoxicidade; Genotoxicidade; Mutagenicidade; Estresse oxidativo
• Link de acesso: http://hdl.handle.net/11449/144608

The decomposition of bodies is considered a pollution resource due to the production of an organic liquid denominated as necrochorume that, besides compromising the environment, it can cause serious problems to human health. In the composition of this liquid, the amine cadaverine can be found (C5H14N2), a highly toxic substance, produced during putrefaction of organic tissues of the bodies in decomposition. Whereas the cemeteries are disposal locals for dead bodies and that the decomposition of the bodies generates toxic substances, like cadaverine, the evaluation of the compromising of the environment, which can be unleashed by this contaminant, becomes very important. Therefore, the present study aimed to evaluate the cytotoxic, genotoxic, mutagenic and oxidative effects of different concentrations of the diamine cadaverine, by ecotoxicological assays performed with the test systems in vitro and in vivo. Three different test organisms were used: Allium cepa, HepG2 and Speedy cells maintained in culture and Wistar rats. With the A. cepa organism, tests for chromosomal aberrations and micronucleus in meristematic cells were applied, which are indicatives of genotoxic and mutagenic effects respectively. The concentrations of 61,5, 184,5 e 307,5, 430,5 e 553,5 mg/L were tested. The elevated frequency of chromosomal adherence and binucleated cells infer an aneugenic action to the cadaverine. Besides, there was no statistically significant difference in the Mitotic Index (MI) values and to the Mutagenicity Index (MutI). Regarding the resazurin assay, performed with cell culture, by using human hepatoma cells (HepG2) and amphibian cells (Speedy), it was possible to observe that the cadaverine was cytotoxic for both cell lines, though, the Speedy cells were more sensible than the HepG2 cells. The comet assay performed with the same cell lines did not show significant damages on the DNA. However, in the cytokinesis-block micronucleus technique there was a significant increase in the frequency of nuclear buds (HepG2 – 184,5 e 307,5 mg/L; Speedy – 30,75, 61,5 e 123,0 mg/L), nuclear bridges (Speedy – 30,75, 61,5 e 123,0 mg/L) and MN (HepG2 – 184,5 e 307,5 mg/L; Speedy – 123,0 mg/L), which indicates a genotoxic and mutagenic action to this diamine. The assays with male Wistar rats were performed by oral administration of the cadaverine, in doses of 15, 30 e 60 mg/kg/day, for an exposition period of 56 consecutive days. To investigate the genotoxic potential in rats, the comet assay was performed with peripheral blood and, from the measurements of the intensity, length and moment of the tail, it was possible to observe that the cadaverine did not cause a significant difference in the DNA breaks when compared to the negative control. By the MN test with bone marrow cells was possible to observe that the cadaverine did not induce cytotoxicity because there was not a significant difference in the Polychromatic Erythrocytes (PCE)/Normochromatic Erythrocytes (NCE) rate. To the MN frequency in PCE, there was a significant increase in the animals treated with the concentration of 30 mg/Kg of cadaverine, considered as an indicative of genomic instability. From these results, we can infer, again, an aneugenic action of the cadaverine. Lastly, the ability of the cadaverine to induce changes in the redox balance of the hepatic cells of Wistar rats was evaluated. The sulfhydryl groups (-SH), GSH levels, the activity of the CAT, SOD, GST enzymes and the lipidic peroxidation (TBARS) were quantified. It was possible to observe a significant increase of the values quantified in the assays to evaluate sulfhydryl groups (-SH), in the group treated with 15 mg/Kg of cadaverine. Although some results have not shown statistically significant difference, it was observed a slight decrease in the GSH levels and an increase in the MDA levels for all tested concentrations. These data indicate that the decrease in the GSH can generate oxygen-reactive species (ERO), which result in the lipidic peroxidation in the liver. Regarding the activity of the enzymes CAT, SOD and GST, there were not significant results for none of the tested concentrations. Thus, the results suggest that the cadaverine can present cytotoxic, genotoxic, mutagenic and oxidative effects, depending on the tested organism. Thereby, by the applied methods in this research, it was also possible to infer some action mechanisms and, thus, contribute to the knowledge of the cadaverine’s toxicity, once that a few studies have been performed in the ecotoxicological area.