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Calcagnotto, M. E.

Publications and source records attributed to Calcagnotto, M. E..

3 recordsLinked to original sources

Neurological effects induced by micro- and nanoplastics in fish: a systematic review and meta-analysis

Plastic is considered an inert material with high durability and minimal to virtually no decomposition. However, when released into the environment, they can degrade into very small particles, forming micro- and nanoplastic particles (MNP). This systematic review and meta-analysis synthesized the evidence from controlled preclinical studies to investigate the neurological effects of MNPs in fish. Following a pre-registered protocol, we searched PubMed, Web of Science, and Scopus for studies exposing fish to virgin MNPs under controlled conditions, reporting behavioral or neurochemical outcomes relevant to central nervous system function. Data were synthesized using a hierarchical random-effects model with robust variance estimation. Fifty-nine studies, comprising 723 comparisons across 13 behavioral and neurochemical outcomes, were included in the meta-analysis. The analysis accounted for correlated effect sizes within shared control groups; and nested identifiers for study, control group, and effect size. Results indicated high heterogeneity and no consistent effect of the MNP exposure on behavioral or neurochemical parameters, except for reduced traveled distance in sensory-motor assays. Meta-regression examined whether developmental stage, exposure duration, and MNP size or concentration moderate these effects. No significant moderators were identified, except for catalase activity, where longer exposure reduced enzyme activity in larvae. The findings should be interpreted with caution, as reporting quality was generally low, with key methodological details often omitted. Additionally, publication bias was found for several outcomes, and influential case analyses revealed that a few studies disproportionately affected the overall estimates. Further studies are needed to clarify the impact of MNPs on fish neurobiology and behavior.

neuroscience↗

Linalool and trans-nerolidol prevent pentylenetetrazole-induced seizures in adult zebrafish

BackgroundLinalool (LIN) and trans-nerolidol (NER) are terpene alcohols found in plant-derived essential oils commonly used in traditional systems of medicine. Both compounds have shown antiseizure, sedative, and antioxidant effects in rodent and in vitro models. Due to their structural similarity, a comparative evaluation of their antiseizure profiles is warranted. This study examined the effects of acute LIN and NER exposure in a pentylenetetrazole (PTZ)-induced seizure model in zebrafish (Danio rerio). MethodsA total of 240 adult zebrafish were randomly assigned to the following groups: blank control (dechlorinated water), vehicle control (1% DMSO), positive control (50 {micro}M diazepam, DZP), and three concentrations of LIN or NER (4, 40, 400 {micro}M). Fish were exposed to treatments for 10 minutes, transferred to a washout beaker with dechlorinated water for 5 minutes, and then transferred to PTZ (10 mM) for 20-minute behavioral recording. Seizure activity was scored by blinded observers (BORIS(R)), and locomotion was analyzed with ANY-maze software. ResultsLIN at 400 {micro}M and NER at 40 and 400 {micro}M significantly prolonged latency to clonic- and tonic-like seizures and reduced seizure severity. Notably, 400 {micro}M NER exceeded DZP in effect size, and 40 {micro}M NER also enhanced locomotor activity. ConclusionLIN and NER delayed progression to severe seizure stages and reduced seizure severity, supporting their antiseizure potential. NER consistently outperformed LIN, demonstrating stronger efficacy than DZP at the highest concentration. Consistent with rodent studies, these findings position both as promising leads for drug development.

neuroscience↗

Chemically-induced epileptic seizures in zebrafish: a systematic review

The use of zebrafish as a model organism is gaining evidence in the field of epilepsy as it may help to understand the mechanisms underlying epileptic seizures. As zebrafish assays became popular, the heterogeneity between protocols increased, making it hard to choose a standard protocol to conduct research while also impairing the comparison of results between studies. We conducted a systematic review to comprehensively profile the chemically-induced seizure models in zebrafish. Literature searches were performed in PubMed, Scopus and Web of Science, followed by a two-step screening process based on inclusion/exclusion criteria. Qualitative data were extracted and a sample of 100 studies was randomly selected for risk of bias assessment. Out of the 1058 studies identified after removing duplicates, 201 met the inclusion criteria. We found that the most common chemoconvulsants used in the reviewed studies were pentylenetetrazole (n = 180), kainic acid (n = 11), and pilocarpine (n = 10), which increase seizure severity in a dose-dependent manner. The main outcomes assessed were seizure scores and locomotion. Significant variability between the protocols was observed for administration route, duration of exposure, and dose/concentration. Of the studies subjected to risk of bias assessment, most were rated as low risk of bias for selective reporting (94%), baseline characteristics of the animals (67%), and blinded outcome assessment (54%). Randomization procedures and incomplete data were rated as unclear in 81% and 68% of the studies, respectively. None of the studies reported the sample size calculation. Overall, these findings underscore the need for improved methodological and reporting practices to enhance reproducibility and reliability of zebrafish models for studying epilepsy. Our study offers a comprehensive overview of the current state of chemically-induced seizure models in zebrafish, highlighting the common chemoconvulsants used and the variability in protocol parameters. This may be particularly valuable to researchers interested in understanding the underlying mechanisms of epileptic seizures and screening potential drug candidates in zebrafish models. HIGHLIGHTS- We systematically reviewed the effects of chemically-induced seizures in zebrafish; - PTZ is the most used epileptic seizure inducer in zebrafish; - More than 50% of the studies fail to report data such as outlier exclusion criteria and sample size estimation; - The results showed a need for better standardization of protocols.

neuroscience↗