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Rocha C.A.M.,Federal University of Para | Pessoa C.M.F.,Federal University of Para | Rodrigues C.A.C.,Federal Rural University of Amazonia | Pinheiro R.H.S.,Federal Rural University of Amazonia | And 3 more authors.
Ecotoxicology and Environmental Safety | Year: 2016

Maintaining water quality within tolerable limits is a basic need of the riverside communities in the Amazon. Using endemic aquatic organisms as biological models is useful for monitoring the environment. In this study, potential cytotoxic and genotoxic damages in Plagioscion squamosissimus (commonly known as silver croaker) from the Marajó Archipelago were evaluated using a flow cytometry assay and a survey of micronuclei (MN) frequency as well as other nuclear abnormalities (NA). P. squamosissimus specimens were collected at four locations in the Marajó Archipelago. Blood samples from these fish were used in the flow cytometry assay and piscine micronucleus test, and the resulting data were analyzed using analysis of variance (ANOVA). We did not observe a difference in the erythrocyte cell cycle distribution among the samples (P=0.9992), which suggests the absence of cytotoxic agent-induced apoptosis. The piscine micronucleus test exhibited differences in the samples from São Sebastião da Boa Vista (SSBV), and those from Anajás produced the highest mutagenicity indices. The MN frequencies were low for all groups, but the groups exhibited significantly different frequencies (P=0.0033). Reniform nuclei, nuclei with extensions, and lobed nuclei were combined and considered NA. The frequency differences for these NA were significant among sampling sites (P <0.0001). This report is the first to use flow cytometry in fish to evaluate cytotoxic agent-induced apoptosis. The micronucleus test results indicate the presence of pollutants that can change the genetic material of the fish studied. We also demonstrate that the Amazonian fish P. squamosissimus is important not only as a comestible species but also as an adequate model for biomonitoring in aquatic environments. © 2016 Elsevier Inc.

Pamplona S.,Federal University of Para | Sa P.,Federal University of Para | Lopes D.,Hospital Universitario Barros Barreto | Costa E.,Hospital Universitario Barros Barreto | And 5 more authors.
Molecules | Year: 2015

Swietenia macrophylla (mahogany) is a highly valued timber species, whereas the leaves are considered to be waste product. A total of 27 phenolic compounds were identified in aqueous extracts from mahogany leaves by comparing retention times and mass spectra data with those of authentic standards using LC-ESI-MS/MS. Polyphenols play an important role in plants as defense mechanisms against pests and pathogens and have potent antioxidant properties. In terms of health applications, interest has increased considerably in naturally occurring antioxidant sources, since they can retard the progress of many important neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. The antioxidant capacities of two aqueous extracts, M1 (decoction) and M2 (infusion), were measured using TEAC and Folin-Ciocalteau methods. Additionally, M1 was used in order to investigate its potential cytoprotective effects on an in vitro model of neurodegeneration, by using primary cerebellar cultures exposed to methyl mercury (MeHg). Under experimental sub-chronic conditions (72 h), concomitant exposure of the same cultures to MeHg and M1 extract resulted in a statistically significant increase in cell viability in all three concentrations tested (10, 50 and 100 μg/mL), strongly suggesting that due to its high content of antioxidant compounds, the M1 extract provides significant cytoprotection against the MeHg-induced in vitro neurotoxicity. © 2015 by the authors; licensee MDPI, Basel, Switzerland.

De Oliveira D.G.,Federal University of Para | De Almeida C.M.C.,Federal University of Para | E Silva C.Y.Y.,Federal University of Para | Arruda M.S.P.,Federal University of Para | And 5 more authors.
Journal of the Brazilian Chemical Society | Year: 2012

Five new flavonoids, 5,3'-dihydroxy-4'-methoxy-2",2"- dimethylchromene-(5",6":6,7)- dihydroflavonol (1), 5,3'-dihydroxy-7,4'-dimethoxy-6,8-dimethylallyl-dihydroflavonol (2), 5,3'-dihydroxy-4'-methoxy-8-allyl-2",2"-dimethylchromene-(5", 6":6,7) flavanone (3), 5,3'-dihydroxy-7,4'-dimethoxy-6,8-dimethylallyl- flavanone (4), 3,5,3'-trihydroxy-7,4'-dimethoxy- 6,8-dimethylallyl-flavanol (5), together with the stilbenes 4-methoxylonchocarpene (6) and lonchocarpene (7) were isolated from the leaves of Deguelia utilis. Their chemical structures were established on the basis of NMR (nuclear magnetic resonance) spectral data and HRESITOF MS (electrospray ionization-high resolution time-of-flight mass spectrometry). Also, in order to investigate potential cytoprotective effects of these flavonoids, we used a fraction eluted with hexane:EtOAc containing all seven flavonoids, in an in vitro model of neurodegeneration, using hippocampal primary cultures from neonatal (PND2-P3) rats exposed to rotenone, a mitochondrial complex I inhibitor. There was a significant reduction in cell viability (19.4 ± 1.6%) when the cultures were exposed to 30 nmol L-1 rotenone for 72 h. Concomitant exposure of the cultures to the FR3 (5 mu;g mL-1) and 30 nmol L-1 rotenone resulted in values of cell viability similar to control groups (99.6 ± 4.8%), strongly suggesting a cytoprotective effect for this flavonoid-rich fraction. © 2012 Sociedade Brasileira de Quimica.

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