Indomethacin treatment prior to pentylenetetrazole-induced seizures downregulates the expression of il1b and cox2 and decreases seizure-like behavior in zebrafish larvae.

Patrícia Gonçalves Barbalho,Claudia Vianna Maurer-Morelli,Iscia Lopes-Cendes

doi:10.1186/s12868-016-0246-y

Patrícia Gonçalves Barbalho, Claudia Vianna Maurer-Morelli + Show 1 more

Open Access

https://doi.org/10.1186/s12868-016-0246-y

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Journal: BMC neuroscience	Publication Date: Mar 9, 2016
Citations: 50	License type: cc-by

Affiliation: Universidade Estadual de Campinas

Abstract

BackgroundIt has been demonstrated that the zebrafish model of pentylenetetrazole (PTZ)-evoked seizures and the well-established rodent models of epilepsy are similar pertaining to behavior, electrographic features, and c-fos expression. Although this zebrafish model is suitable for studying seizures, to date, inflammatory response after seizures has not been investigated using this model. Because a relationship between epilepsy and inflammation has been established, in the present study we investigated the transcript levels of the proinflammatory cytokines interleukin-1 beta (il1b) and cyclooxygenase-2 (cox2a and cox2b) after PTZ-induced seizures in the brain of zebrafish 7 days post fertilization. Furthermore, we exposed the fish to the nonsteroidal anti-inflammatory drug indomethacin prior to PTZ, and we measured its effect on seizure latency, number of seizure behaviors, and mRNA expression of il1b, cox2b, and c-fos. We used quantitative real-time PCR to assess the mRNA expression of il1b, cox2a, cox2b, and c-fos, and visual inspection was used to monitor seizure latency and the number of seizure-like behaviors.ResultsWe found a short-term upregulation of il1b, and we revealed that cox2b, but not cox2a, was induced after seizures. Indomethacin treatment prior to PTZ-induced seizures downregulated the mRNA expression of il1b, cox2b, and c-fos. Moreover, we observed that in larvae exposed to indomethacin, seizure latency increased and the number of seizure-like behaviors decreased.ConclusionsThis is the first study showing that il1b and cox-2 transcripts are upregulated following PTZ-induced seizures in zebrafish. In addition, we demonstrated the anticonvulsant effect of indomethacin based on (1) the inhibition of PTZ-induced c-fos transcription, (2) increase in seizure latency, and (3) decrease in the number of seizure-like behaviors. Furthermore, anti-inflammatory effect of indomethacin is clearly demonstrated by the downregulation of the mRNA expression of il1b and cox2b. Our results are supported by previous evidences suggesting that zebrafish is a suitable alternative for studying inflammation, seizures, and the effect of anti-inflammatory compounds on seizure suppression.

Highlights

It has been demonstrated that the zebrafish model of pentylenetetrazole (PTZ)-evoked seizures and the well-established rodent models of epilepsy are similar pertaining to behavior, electrographic features, and c-fos expression
The mRNA expression of cox2a and cox2b in the brain of zebrafish larvae after PTZ‐induced seizures Because no significant differences were found in the mRNA expression of il1b pertaining to longer time periods, we chose to evaluate the temporal expression profile of cox2a and cox2b 0.05, 1, and 6 h after PTZ-induced seizures
Our results revealed that indomethacin treatment prior to PTZ-induced seizures downregulated the mRNA expression of il1b, cox2b, and c-fos

Summary

Introduction

It has been demonstrated that the zebrafish model of pentylenetetrazole (PTZ)-evoked seizures and the well-established rodent models of epilepsy are similar pertaining to behavior, electrographic features, and c-fos expression. Zebrafish experimental models are widely accepted for investigating human diseases, including epilepsy [1,2,3,4] Importance of this animal model is mainly based on its remarkable features combining exceptionally simple genetic manipulations, which are ideal for forward and reverse genetic investigations, and easy phenotype assessment in a short period of time. Other advantages of this fish species are as follows: low maintenance cost, easy breeding, high fecundity, external fertilization and development, short generation time, and transparency during embryonic and larval stage. Zebrafish are sensitive to common anticonvulsant drugs; they are widely used for the high throughput screening of novel antiepileptic drugs (AEDs) [7,8,9,10,11,12,13]

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