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Do Val-da Silva R.A.,University of Sao Paulo | Peixoto-Santos J.E.,University of Sao Paulo | Kandratavicius L.,University of Sao Paulo | Kandratavicius L.,National Institute of Science and Technology for Translational Medicine | And 14 more authors.
Frontiers in Pharmacology | Year: 2017

The present study reports the behavioral, electrophysiological, and neuropathological effects of cannabidiol (CBD), a major non-psychotropic constituent of Cannabis sativa, in the intrahippocampal pilocarpine-induced status epilepticus (SE) rat model. CBD was administered before pilocarpine-induced SE (group SE+CBDp) or before and after SE (group SE+CBDt), and compared to rats submitted only to SE (SE group), CBD, or vehicle (VH group). Groups were evaluated during SE (behavioral and electrophysiological analysis), as well as at days one and three post-SE (exploratory activity, electrophysiological analysis, neuron density, and neuron degeneration). Compared to SE group, SE+CBD groups (SE+CBDp and SE+CBDt) had increased SE latency, diminished SE severity, increased contralateral afterdischarge latency and decreased relative powers in delta (0.5-4 Hz) and theta (4-10 Hz) bands. Only SE+CBDp had increased vertical exploratory activity 1-day post SE and decreased contralateral relative power in delta 3 days after SE, when compared to SE group. SE+CBD groups also showed decreased neurodegeneration in the hilus and CA3, and higher neuron density in granule cell layer, hilus, CA3, and CA1, when compared to SE group. Our findings demonstrate anticonvulsant and neuroprotective effects of CBD preventive treatment in the intrahippocampal pilocarpine epilepsy model, either as single or multiple administrations, reinforcing the potential role of CBD in the treatment of epileptic disorders. © 2017 Do Val-da Silva, Peixoto-Santos, Kandratavicius, De Ross, Esteves, De Martinis, Alves, Scandiuzzi, Hallak, Zuardi, Crippa and Leite.

Senger M.R.,Oswaldo Cruz Institute FIOCRUZ | Senger M.R.,Federal University of Rio Grande do Sul | Seibt K.J.,Pontifical Catholic University of Rio Grande do Sul | Seibt K.J.,National Institute of Science and Technology for Translational Medicine | And 7 more authors.
Cell Biology and Toxicology | Year: 2011

Aluminum is a metal that is known to impact fish species. The zebrafish has been used as an attractive model for toxicology and behavioral studies, being considered a model to study environmental exposures and human pathologies. In the present study, we have investigated the effect of aluminum exposure on brain acetylcholinesterase activity and behavioral parameters in zebrafish. In vivo exposure of zebrafish to 50 μg/L AlCl3 for 96 h at pH 5.8 significantly increased (36%) acetylthiocholine hydrolysis in zebrafish brain. There were no changes in acetylcholinesterase (AChE) activity when fish were exposed to the same concentration of AlCl3 at pH 6.8. In vitro concentrations of AlCl3 varying from 50 to 250 μM increased AChE activity (28% to 33%, respectively). Moreover, we observed that animals exposed to AlCl3 at pH 5.8 presented a significant decrease in locomotor activity, as evaluated by the number of line crossings (25%), distance traveled (14.1%), and maximum speed (24%) besides an increase in the absolute turn angle (12.7%). These results indicate that sublethal levels of aluminum might modify behavioral parameters and acetylcholinesterase activity in zebrafish brain. © Springer Science+Business Media B.V. 2011.

Lemes G.A.F.,Grande Rio University | Kist L.W.,Pontifical Catholic University of Rio Grande do Sul | Bogo M.R.,Pontifical Catholic University of Rio Grande do Sul | Bogo M.R.,National Institute of Science and Technology for Translational Medicine | Yunes J.S.,Grande Rio University
Journal of Venomous Animals and Toxins Including Tropical Diseases | Year: 2015

Background: Toxic cyanobacterial blooms are recurrent in Patos Lagoon, in southern Brazil. Among cyanotoxins, [D-Leu1] microcystin-LR is the predominant variant whose natural cycle involves water and sediment compartments. This study aimed to identify and isolate from sediment a bacterial strain capable of growing on [D-Leu1] microcystin-LR. Sediment and water samples were collected at two distinct aquatic spots: close to the Oceanographic Museum (P1), in Rio Grande City, and on São Lourenço Beach (P2), in São Lourenço do Sul City, southern Brazil.Methods: [D-Leu1] microcystin-LR was isolated and purified from batch cultures ofMicrocystis aeruginosastrain RST9501. Samples of water and sediment from Rio Grande and São Lourenço do Sul were collected. Bacteria from the samples were allowed to grow in flasks containing solely [D-Leu1] microcystin-LR. This strain named DMSX was isolated on agar MSM with 8 g L-1glucose and further purified on a cyanotoxin basis growth. Microcystin concentration was obtained by using the ELISA immunoassay for microcystins whereas bacterial count was performed by epifluorescence microscopy. The genusPseudomonaswas identified by DNA techniques.Results: Although several bacterial strains were isolated from the samples, only one, DMXS, was capable of growing on [D-Leu1] microcystin-LR. The phylogenetic analysis of the 16S rRNA gene from DMXS strain classified the organism asPseudomonas aeruginosa. DMXS strain incubated with [D-Leu1] microcystin-LR lowered the amount of toxin from 1 μg.L-1to < 0.05 μg.L-1. Besides, an increase in the bacterial count-from 71 × 105bacteria.mL-1to 117 × 105bacteria.mL-1-was observed along the incubation.Conclusions: The use of bacteria isolated from sediment for technological applications to remove toxic compounds is viable. Studies have shown that sediment plays an important role as a source of bacteria capable of degrading cyanobacterial toxins. This is the first Brazilian report on a bacterium-of the genusPseudomonas-that can degrade [D-Leu1] microcystin-LR, the most frequent microcystin variant in Brazilian freshwaters. © 2015 Lemes et al.; licensee BioMed Central.

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