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Epilepsy is one of the most common neurological diseases, and current antiepileptic drugs fail to suppress seizure occurrence in around one third of epileptic patients. Curcumin is a phytochemical with promising effects on epilepsy treatment. However, its application has been hindered by its low bioavailability. In order to improve curcumin’s anti-seizure properties, increasing its bioavailability, here we proposed to micronize the compound through supercritical carbon dioxide processing, a suitable green chemistry technique to prepare and modify material properties. Here we investigated the anti-seizure potential of the classical antiepileptic drug valproate, curcumin in its natural state, and micronized curcumin in a PTZ-induced seizure model in zebrafish (Danio rerio). Concerning seizure development, valproate, curcumin and micronized curcumin showed protective effects, slowing seizure development both in larvae and adult animals. Nevertheless, considering the occurrence of the tonic-clonic seizure stage, only valproate and micronized curcumin reduced it, both in larvae and adult zebrafish, unlike non-processed curcumin. Our obtained results are very promising, since micronized curcumin showed effects that are similar to a classic antiepileptic drug, reducing seizure occurrence and slowing seizure progression.

The Sinos River, in southern Brazil, is polluted by industrial discharges and untreated urban wastes. Fish genotoxicity biomarkers are valuable parameters for environmental risk assessment. In this study, we used the comet assay to detect genotoxicity due to multiple sources of pollution in the peripheral blood of a native fish species (Hyphessobrycon luetkenii). In addition, we analysed possible DNA damage from aluminum, lead, chromium, copper, nickel, iron and zinc contamination. Water samples were collected seasonally from three sampling sites and the fish were assessed under laboratory conditions. Water chemical analysis showed an increased level of aluminum and iron in most of the samples at sites 2 and 3, located in the middle and lower river course, respectively. The index of DNA damage assessed by the comet assay demonstrated no significant differences in different seasons or at the different sampling sites, while the frequency of cells with DNA damage was higher in water samples collected at sites 1 and 2 during the spring season. None of the metals studied seems to be associated with the increase in the frequency of cells with DNA damage observed during the spring season. The results of this study indicate that the Sinos River is contaminated with substances that are genotoxic to fish, including the waters near the river spring.Keywords: genotoxicity, river pollution, biomarkers, metals. Avaliação da genotoxicidade da água do rio dosSinos utilizando o ensaio cometa em peixes ResumoO rio dos Sinos, no sul do Brasil, é poluído tanto por descargas industriais como por resíduos urbanos não tratados. Os biomarcadores de genotoxicidade em peixes são parâmetros valiosos para a determinação de risco ambiental. Neste estudo, utilizamos o ensaio cometa em sangue periférico de um peixe nativo (Hyphessobrycon luetkenii) para detectar a genotoxicidade devido a múltiplas fontes de poluição. Além disso, analisamos a possível influência da contaminação por alumínio, chumbo, cromo, cobre, níquel, ferro e zinco sobre o dano de DNA. Amostras de água foram coletadas sazonalmente em três pontos de coleta e os peixes foram expostos sob condições de laboratório. A análise química da água mostrou níveis elevados de alumínio e ferro na maioria das amostras dos pontos 2 e 3, localizados nos cursos médio e inferior do rio, respectivamente. O índice de dano de DNA estimado pelo ensaio cometa não demonstrou diferenças significativas tanto entre estações como entre pontos de coleta, enquanto que a frequência de células com dano de DNA apresentou valores superiores nas amostras de água coletadas durante a primavera nos pontos 1 e 2. Nenhum dos metais estudados parece estar associado com o aumento na frequência de células com dano de DNA observado durante a primavera. Os resultados deste estudo indicam que o rio dos Sinos está contaminado com substâncias genotóxicas para os peixes, incluindo as águas próximas à nascente do rio. results. Moreover, genotoxicity assays in fish erythrocytes has not been used to evaluate the genot...

Despite the extensive knowledge about the effects of acute restraint stress (ARS) in rodents, zebrafish research is still elementary in this field, and the consequences of stress on purinergic system are unclear. Therefore, we evaluated the effects of ARS on behavior, biochemical, and molecular parameters in zebrafish brain. Animals were submitted to a 90 min ARS protocol and tested for anxiety levels, exploratory behavior, and memory performance. Furthermore, we analyzed ectonucleotidase and adenosine deaminase activities and their gene expression profile, as well as transcription of adenosine receptors. ARS increased anxiety, but did not impair locomotion or cognition. ARS significantly increased ATP hydrolysis, decreased cytosolic ADA activity, and changed the entpd and adora gene expression. In conclusion, ARS disturbed zebrafish behavior, and we hypothesize that the augmentation in adenosine-mediated signaling may be a strategy to reestablish homeostasis and normal behavior after a stressful event.