Acute Toxicity Screening of Novel AChE Inhibitors Using Neuronal Networks on Microelectrode Arrays

• Published in: Neurotoxicology (Park Forest South) Vol. 22; no. 1; pp. 3 - 12
• Main Authors: Keefer, Edward W., Norton, Scott J., Boyle, Nicholas A.J., Talesa, Vincenzo, Gross, Guenter W.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Orlando, FL Elsevier B.V 01.02.2001; Elsevier
• Subjects: AChE; Alzheimer; Animals; Bio-sensors; Biological and medical sciences; bisthiocarbonates; Cholinergic Agonists - pharmacology; Cholinergic Antagonists - pharmacology; Cholinesterase Inhibitors - toxicity; Culture Media; Drug Evaluation, Preclinical; Drug screening; Drug toxicity and drugs side effects treatment; Extracellular multichannel recording; Medical sciences; Mice; Mice, Inbred ICR; Microelectrodes; Neural Networks (Computer); Neurons - drug effects; Pharmacology. Drug treatments; physostigmine; Physostigmine - pharmacology; Prefrontal Cortex - cytology; Substrate-integrated electrode arrays; Synaptic Transmission - drug effects; thiocarbamates; Toxicity: nervous system and muscle; AChE; Extracellular multichannel recording; Bio-sensors; Drug screening; Alzheimer; Substrate-integrated electrode arrays; Animal model; Agonist; Embryo; Toxicity; Central nervous system; Action potential; Esterases; Frontal cortex; Acetylcholinesterase; Dose activity relation; Organic thiocarbonate; Cholinergic receptor; Investigation method; Alkyl; Antagonist; Anticholinesterase agent; Nervous system diseases; Enzyme; Rodentia; Enzyme inhibitor; In vitro; Carboxylic ester hydrolases; Cerebral disorder; Vertebrata; Mammalia; Mouse; Animal; Central nervous system disease; Hydrolases; Brain (vertebrata); Cholinergic transmission
• ISSN: 0161-813X; 1872-9711
• DOI: 10.1016/S0161-813X(00)00014-0

Spontaneously active neuronal networks grown from embryonic murine frontal cortex on substrate integrated electrode arrays with 64 recording sites were used to assess acute neurobiological and toxic effects of a series of seven symmetrical, bifunctional alkylene-linked bis-thiocarbonate compounds designed to possess anticholinesterase activity. Acute functional neurotoxicity in the absence of cytotoxicity was defined as total collapse of spontaneous activity. All of the compounds were characterized as mixed inhibitors of AChE, with K i ’s in the 10 −7–10 −6 M range. The neuronal network assays revealed high repeatability for each compound, but surprisingly diverse effects among these closely related compounds. Six of the seven compounds produced changes in network activity at concentrations of 10–350 μM. Three of the compounds were excitatory, two were biphasic (excitatory at lower concentrations, inhibitory at higher), and one was solely inhibitory. Two of the inhibitory compounds produced irreversible inhibition of activity. Responses of cortical cultures to eserine were compared to the effects produced by the test compounds, with only one of seven providing a close match to the eserine profile. Matching of response patterns allows the classification of new drugs according to their response similarity to well-characterized agents. Spontaneously active neuronal networks reflect the interactions of multiple neurotransmitter and receptor systems, and can reveal unexpected side effects due to secondary binding. Utilizing such networks holds the promise of greater research efficiency through a more rapid recognition of physiological tissue responses.