Assessing neurological and cardiovascular effects caused by pharmaceuticals in river water: Insights from Daphnia magna and Danio rerio embryos.

Pharmaceutical residues in surface waters are an emerging environmental and public health issue, yet their biological impacts on aquatic life remain poorly understood. This study presents a cost-effective bioanalytical framework using Daphnia magna juveniles and zebrafish (Danio rerio) embryos to evaluate neurotoxic and cardiotoxic effects of pharmaceutical mixtures in rivers downstream of wastewater treatment plant (WWTP) effluents. Water samples from three rivers in north-eastern Spain (Besòs, Llobregat, and Onyar) were concentrated up to 5- and 20-fold using solid-phase extraction.

Assessing cisplatin-induced acute toxicity in zebrafish (Danio rerio): a multi-organ perspective at realistic concentrations.

Cisplatin, a widely used platinum-based chemotherapeutic agent, has been detected in hospital effluents and wastewater treatment plant discharges, raising concerns about its potential ecological impact, particularly on aquatic organisms. Despite its significant presence in environmental matrices, limited studies have investigated the effects of cisplatin at concentrations within the lower range of those reported in wastewater treatment plant effluents (< 150 μg/L) on fish health. This study aimed to assess the impact of cisplatin (2, 5, 10 μg/L) on zebrafish (Danio rerio) by evaluating oxidative stress responses and gene expression alterations in critical organs, including the liver, brain, gut, and gills.

Ultra-sensitive UHPLC-MS/MS method for simultaneous quantification of 31 neurochemicals in zebrafish larvae and brain.

The precise determination of neurotransmitters and their metabolites in biological matrices is critical for research on neurological disorders, including those originated by the exposure to neurotoxic chemicals. This study presents an optimized liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for 31 neurochemicals, including neurotransmitters, their metabolites and precursors. The method is aimed at achieving lower limits of detection (LOD) and quantification (LOQ) compared to those currently available, while simultaneously expanding the number of compounds analyzed.

N-Acetylcysteine-Amide Protects Against Acute Acrylamide Neurotoxicity in Adult Zebrafish.

Acrylamide (ACR) is a potent neurotoxicant that disrupts cellular redox homeostasis by depleting reduced glutathione (GSH) and inducing oxidative stress. Despite its well-characterized mechanism, no effective treatments for ACR-induced neurotoxicity currently exist. This study evaluates the therapeutic efficacy of N-acetylcysteine-amide (AD4), a blood-brain barrier (BBB)-permeable derivative of N-acetylcysteine, in a novel severe acute ACR neurotoxicity model in adult zebrafish.

Analytical study, environmental risk assessment, and toxicity-based bioassays of effluents from phosphate fertilizer industry: a case study in Gafsa mining basin (SW Tunisia).

The phosphate fertilizer industry (PFI) in M'dhilla-Gafsa, Tunisia, discharges untreated effluents, creating environmental concerns due to unknown composition and toxic effects, leading to potential ecological and human health risks. This study characterized wastewater from three sampling points (SP1, SP2, SP3), and revealed their high acidity pH (2-3) and salinity (32.5-96.

Motor and Non-Motor Effects of Acute MPTP in Adult Zebrafish: Insights into Parkinson's Disease.

Parkinson's disease (PD), the second most common neurodegenerative disorder, is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta, leading to motor and non-motor symptoms. The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) has been extensively used in different animal species to develop chemical models of PD. This study aimed to evaluate the effects of acute exposure to MPTP (3 × 150 mg/kg, intraperitoneally) on adult zebrafish by assessing the neurochemical, transcriptional, and motor changes associated with PD pathogenesis.

Fluoroquinolone and sulfonamide antibiotics (single and mixtures) impair the motor function of zebrafish larvae at environmentally relevant concentrations.

The occurrence of antibiotics in freshwater is a global concern, with evidence pointing to potential neurotoxic effects after prolonged exposure. However, data on their impact on behavior, particularly at environmentally relevant concentrations, remain limited. This study examined the motor function of zebrafish larvae exposed to single and mixture of antibiotics from the sulfonamide and fluoroquinolone classes.

Zebra_K, a kinematic analysis automated platform for assessing sensitivity, habituation and prepulse inhibition of the acoustic startle response in adult zebrafish.

The acoustic startle response (ASR) is leaded by a sudden and intense acoustic stimulus. ASR has several forms of plasticity, including habituation and sensorimotor gating. Although ASR and its plasticity have been intensively studied in zebrafish (Danio rerio) larvae, information in adult zebrafish is still very scarce.

Analyzing the neurotoxic effects of anatoxin-a and saxitoxin in zebrafish larvae.

Global warming due to climate change, as well as freshwater eutrophication caused by anthropogenic activities are responsible, among other factors, for an increasing occurrence of harmful algal blooms (HABs) in aquatic systems. These can lead to the generation of cyanotoxins, secondary metabolites coming from cyanobacteria, producing adverse effects in living organisms including death. This research aims to study the effects that two neurotoxins, anatoxin-a (ATX-a) and saxitoxin (STX), have on living organisms.

Understanding the impact of environmentally relevant alkyl C12-16 dimethylbenzyl ammonium chloride concentrations on zebrafish health.

Alkyldimethylbenzylammonium chlorides (ADBACs), classified as second-generation quaternary ammonium compounds, are extensively employed across various sectors, encompassing veterinary medicine, food production, pharmaceuticals, cosmetics, ophthalmology, and agriculture. Consequently, significant volumes of ADBAC C12-C16 are discharged into the environment, posing a threat to aquatic organisms. Regrettably, comprehensive data regarding the toxicological characteristics of these compounds remain scarce.

The 10th Anniversary of : Recent Advances in Toxicology Research.

Last year (2023) was the tenth anniversary of [...

Polluted water from a storage dam (Villa Victoria, méxico) induces oxidative damage, AChE activity, embryotoxicity, and behavioral changes in Cyprinus carpio larvae.

The Villa Victoria dam is one of the most important storage reservoirs in Mexico since it distributes water to more than 20 million inhabitants in the Metropolitan Zone of Mexico City. In this dam, the common carp (Cyprinus carpio) is an important food resource for the inhabitants, so the aim of this work was to evaluate the oxidative damage (lipoperoxidation, oxidized proteins, antioxidant enzymes activity and gene expression), AChE, embryotoxicity and behavioral changes in C. carpio embryos and larvae exposed to water from Villa Victoria dam for 24, 48, 72 and 96 h.

Analyzing the Effects of Age, Time of Day, and Experiment on the Basal Locomotor Activity and Light-Off Visual Motor Response Assays in Zebrafish Larvae.

The recent availability of commercial platforms for behavioral analyses in zebrafish larvae based on video-tracking technologies has exponentially increased the number of studies analyzing different behaviors in this model organism to assess neurotoxicity. Among the most commonly used assays in zebrafish larvae are basal locomotor activity (BLA) and visual motor responses (VMRs). However, the effect of different intrinsic and extrinsic factors that can significantly alter the outcome of these assays is still not well understood.

Cardiac and neurobehavioral impairments in three phylogenetically distant aquatic model organisms exposed to environmentally relevant concentrations of boscalid.

Boscalid (2-Chloro-N-(4'-chlorobiphenyl-2-yl) nicotinamide), a pyridine carboxamide fungicide, is an inhibitor of the complex II of the respiration chain in fungal mitochondria. As boscalid is only moderately toxic for aquatic organisms (LC > 1-10 mg/L), current environmental levels of this compound in aquatic ecosystems, in the range of ng/L-μg/L, are considered safe for aquatic organisms. In this study, we have exposed zebrafish (Danio rerio), Japanese medaka (Oryzias latipes) and Daphnia magna to a range of concentrations of boscalid (1-1000 μg/L) for 24 h, and the effects on heart rate (HR), basal locomotor activity (BLA), visual motor response (VMR), startle response (SR), and habituation (HB) to a series of vibrational or light stimuli have been evaluated.

Developmental defects in cognition, metabolic and cardiac function following maternal exposures to low environmental levels of selective serotonin re-uptake inhibitors and tributyltin in Daphnia magna.

Aquatic organisms are exposed to low concentrations of neuro-active chemicals, many of them acting also as neuroendocrine disruptors that can be hazardous during earlier embryonic stages. The present study aims to assess how exposure early in live to environmental low concentrations of two selective serotonin reuptake inhibitors (SSRIs), fluoxetine and sertraline, and tributyltin (TBT) affected cognitive, metabolic and cardiac responses in the model aquatic crustacean Daphnia magna. To that end, newly brooded females were exposed for an entire reproductive cycle (3-4 days) and the response of collected juveniles in the first, second and third consecutive broods, which were exposed, respectively, as embryos, provisioned and un-provisioned egg stages, was monitored.

Short-term exposure to environmental levels of nicotine and cotinine impairs visual motor response in zebrafish larvae through a similar mode of action: Exploring the potential role of zebrafish α7 nAChR.

The current view is that environmental levels of nicotine and cotinine, commonly in the ng/L range, are safe for aquatic organisms. In this study, 7 days post-fertilization zebrafish embryos have been exposed for 24 h to a range of environmental concentrations of nicotine (2.0 ng/L-2.

Analysis of sleep/wake cycles in zebrafish larvae.

Zebrafish larvae are a model organism increasingly used in the study of the effect of neuroactive chemicals on vertebrate sleep/wake cycles. Sleep disturbances have a negative impact on mood, cognition and overall health. Here we present a protocol to assess over 24 h sleep/wake cycles in zebrafish larvae subjected to 12 h light/dark periods in 48-well plates, using video-tracking technologies.

Neurotoxicity Assessment in Adult Danio rerio using a Battery of Behavioral Tests in a Single Tank.

The presence of neuropathological effects proved to be, for many years, the main endpoint for assessing the neurotoxicity of a chemical substance. However, in the last 50 years, the effects of chemicals on the behavior of model species have been actively investigated. Progressively, behavioral endpoints were incorporated into neurotoxicological screening protocols, and these functional outcomes are now routinely used to identify and determine the potential neurotoxicity of chemicals.

Environmental concentrations of tire rubber-derived 6PPD-quinone alter CNS function in zebrafish larvae.

N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6PPD-quinone) is a degradation product of 6PPD, an antioxidant widely used in rubber tires. 6PPD-quinone enters aquatic ecosystems through urban stormwater runoff and has been identified as the chemical behind the urban runoff mortality syndrome in coho salmon. However, the available data suggest that the acute effects of 6PPD-quinone are restricted to a few salmonid species and that the environmental levels of this chemical should be safe for most fish.