Culture of Rat Primary Cortical Cells for Microelectrode Array (MEA) Recordings to Screen for Acute and Developmental Neurotoxicity.

Neurotoxicity testing of chemicals, drug candidates, and environmental pollutants still relies on extensive in vivo studies that are very costly, time-consuming, and ethically debated due to the large number of animals typically used. Currently, rat primary cortical cultures are widely used for in vitro neurotoxicity studies, as they closely resemble the in vitro brain with respect to the diversity of cell types, their physiological functions, and the pathological processes that they undergo. Common in vitro assays for neurotoxicity screening often focus on very target-specific endpoints such as morphological, biochemical, or electrophysiological changes, and such narrow focus can hamper translation and interpretation.

Applicability of hiPSC-Derived Neuronal Cocultures and Rodent Primary Cortical Cultures for In Vitro Seizure Liability Assessment.

Seizures are life-threatening adverse drug reactions which are investigated late in drug development using rodent models. Consequently, if seizures are detected, a lot of time, money and animals have been used. Thus, there is a need for in vitro screening models using human cells to circumvent interspecies translation.

Towards animal-free neurotoxicity screening: Applicability of hiPSC-derived neuronal models for in vitro seizure liability assessment.

A sizeable proportion of drug attrition is due to drug-induced seizures. Current available animal models frequently fail to predict human seizure liability. Therefore, there is a need for in vitro alternatives, preferably based on human-derived neurons to circumvent interspecies translation.

Human iPSC-derived neuronal models for in vitro neurotoxicity assessment.

Neurotoxicity testing still relies on ethically debated, expensive and time consuming in vivo experiments, which are unsuitable for high-throughput toxicity screening. There is thus a clear need for a rapid in vitro screening strategy that is preferably based on human-derived neurons to circumvent interspecies translation. Recent availability of commercially obtainable human induced pluripotent stem cell (hiPSC)-derived neurons and astrocytes holds great promise in assisting the transition from the current standard of rat primary cortical cultures to an animal-free alternative.

Chronic 14-day exposure to insecticides or methylmercury modulates neuronal activity in primary rat cortical cultures.

There is an increasing demand for in vitro test systems to detect neurotoxicity for use in chemical risk assessment. In this study, we evaluated the applicability of rat primary cortical cultures grown on multi-well micro-electrode arrays (mwMEAs) to detect effects of chronic 14-day exposure to structurally different insecticides or methylmercury on neuronal activity (mean spike rate; MSR). Effects of chronic exposure to α-cypermethrin, endosulfan, carbaryl, chlorpyrifos(-oxon), methylmercury or solvent control [14days exposure, initiated after baseline recording at day in vitro (DIV)7] were studied in five successive recordings between DIV10 and DIV21.

Organic solvent-induced changes in membrane geometry in human SH-SY5Y neuroblastoma cells - a common narcotic effect?

Exposure to organic solvents may cause narcotic effects. At the cellular level, these narcotic effects have been associated with a reduction in neuronal excitability caused by changes in membrane structure and function. In order to critically test whether changes in membrane geometry contribute to these narcotic effects, cultured human SH-SY5Y neuroblastoma cells have been exposed to selected organic solvents.

In Vitro Developmental Neurotoxicity Following Chronic Exposure to 50 Hz Extremely Low-Frequency Electromagnetic Fields in Primary Rat Cortical Cultures.

Exposure to 50-60 Hz extremely low-frequency electromagnetic fields (ELF-EMFs) has increased considerably over the last decades. Several epidemiological studies suggested that ELF-EMF exposure is associated with adverse health effects, including neurotoxicity. However, these studies are debated as results are often contradictory and the possible underlying mechanisms are unknown.

Detection of marine neurotoxins in food safety testing using a multielectrode array.

Scope: At the European level, detection of marine neurotoxins in seafood is still based on ethically debated and expensive in vivo rodent bioassays. The development of alternative methodologies for the detection of marine neurotoxins is therefore of utmost importance. We therefore investigated whether and to what extent a multielectrode array (MEA) approach can be used as an in vitro alternative for screening of marine neurotoxins potentially present in seafood.

Characterization of calcium responses and electrical activity in differentiating mouse neural progenitor cells in vitro.

In vitro methods for developmental neurotoxicity (DNT) testing have the potential to reduce animal use and increase insight into cellular and molecular mechanisms underlying chemical-induced alterations in the development of functional neuronal networks. Mouse neural progenitor cells (mNPCs) differentiate into nervous system-specific cell types and have proven valuable to detect DNT using biochemical and morphological techniques. We therefore investigated a number of functional neuronal parameters in primary mNPCs to explore their applicability for neurophysiological in vitro DNT testing.

Hexabromocyclododecane inhibits depolarization-induced increase in intracellular calcium levels and neurotransmitter release in PC12 cells.

Environmental levels of the brominated flame retardant (BFR) hexabromocyclododecane (HBCD) have been increasing. HBCD has been shown to cause adverse effects on learning and behavior in mice, as well as on dopamine uptake in rat synaptosomes and synaptic vesicles. For other BFRs, alterations in the intracellular Ca(2+) homeostasis have been observed.

Hydroxylation increases the neurotoxic potential of BDE-47 to affect exocytosis and calcium homeostasis in PC12 cells.

Background: Oxidative metabolism, resulting in the formation of hydroxylated polybrominated diphenyl ether (PBDE) metabolites, may enhance the neurotoxic potential of brominated flame retardants.

Objective: Our objective was to investigate the effects of a hydroxylated metabolite of 2,2',4,4'-tetra-bromodiphenyl ether (BDE-47; 6-OH-BDE-47) on changes in the intracellular Ca2+ concentration ([Ca2+]i) and vesicular catecholamine release in PC12 cells.

Methods: We measured vesicular catecholamine release and [Ca2+]i using amperometry and imaging of the fluorescent Ca2+-sensitive dye Fura-2, respectively.

A noncompetitive, sequential mechanism for inhibition of rat alpha4beta2 neuronal nicotinic acetylcholine receptors by carbamate pesticides.

The mechanism by which carbamate pesticides inhibit rat alpha4beta2 nicotinic acetylcholine (ACh) receptors (nAChRs) expressed in Xenopus laevis oocytes has been investigated using the two-electrode voltage clamp technique. Carbaryl, S-ethyl N,N-dipropylthiocarbamate (EPTC), and fenoxycarb inhibit ACh-induced ion currents in a concentration-dependent way. EPTC and fenoxycarb inhibit ion currents induced by 1 mM ACh with 3-fold to 5-fold higher potency than ion currents induced by 1 microM ACh.