DNA damage in the kidney tissue cells of the fish Rhamdia quelen after trophic contamination with aluminum sulfate.

Even though aluminum is the third most common element present in the earth's crust, information regarding its toxicity remains scarce. It is known that in certain cases, aluminum is neurotoxic, but its effect in other tissues is unknown. The aim of this work was to analyze the genotoxic potential of aluminum sulfate in kidney tissue of the fish Rhamdia quelen after trophic contamination for 60 days. Sixty four fish were subdivided into the following groups: negative control, 5 mg, 50 mg and 500 mg of aluminum sulfate per kg of fish. Samples of the posterior kidney were taken and prepared to obtain mitotic metaphase, as well as the comet assay. The three types of chromosomal abnormalities (CA) found were categorized as chromatid breaks, decondensation of telomeric region, and early separation of sister chromatids. The tests for CA showed that the 5 mg/kg and 50 mg/kg doses of aluminum sulfate had genotoxic potential. Under these treatments, early separation of the sister chromatids was observed more frequently and decondensation of the telomeric region tended to increase in frequency. We suggest that structural changes in the proteins involved in DNA compaction may have led to the decondensation of the telomeric region, making the DNA susceptible to breaks. Moreover, early separation of the sister chromatids may have occurred due to changes in the mobility of chromosomes or proteins that keep the sister chromatids together. The comet assay confirmed the genotoxicity of aluminum sulfate in the kidney tissue of Rhamdia quelen at the three doses of exposure.

Assessment of the genotoxic, antigenotoxic, and cytotoxic activities of the ethanolic fruit extract of Solanum lycocarpum A. St. Hill. (Solanaceae) by micronucleus test in mice.

Solanum lycocarpum A. St. Hill. (Family Solanaceae), popularly known in Brazil as lobeira, is a common weed in the Brazilian Cerrado vegetation. The fruits of this species have been used in Brazil for culinary purposes and in folk medicine as a sedative, diuretic, antiepileptic, antispasmodic, hypoglycemic, and hypocholesterolemic agent as well as in the control of obesity. Due to the spreading use of this plant as a therapeutic resource and food, the present study aimed to evaluate the genotoxic, antigenotoxic, and cytotoxic effects of S. lycocarpum ethanolic fruit extract using the mouse bone marrow micronucleus test. Both genotoxicity and antigenotoxicity of this ethanolic fruit extract were evaluated by using the frequency of micronucleated polychromatic erythrocytes, whereas cytotoxicity was assessed by the polychromatic and normochromatic erythrocytes ratio. Our results indicated that although S. lycocarpum ethanolic fruit extract did not exhibit genotoxic effect in mice bone marrow, both cytotoxic and antigenotoxic actions were evidenced at all tested doses.