title: Morphometric assessment of toxicant induced neuronal degeneration in full and restricted contact co-cultures of embryonic cortical rat neurons and astrocytes: using m-Dinitrobezene as a model neurotoxicant.
abstract: With m-Dinitrobenzene (m-DNB) as a selected model neurotoxicant, we demonstrate how to assess neurotoxicity, using morphology based measurement of neurite degeneration, in a conventional "full-contact" and a modern "restricted-contact" co-culture of rat cortical neurons and astrocytes. In the "full-contact" co-culture, neurons and astrocytes in complete physical contact are "globally" exposed to m-DNB. A newly emergent "restricted-contact" co-culture is attained with a microfluidic device that polarizes neuron somas and neurites into separate compartments, and the neurite compartment is "selectively" exposed to m-DNB. Morphometric analysis of the neuronal area revealed that m-DNB exposure produced no significant change in mean neuronal cell area in "full-contact" co-cultures, whereas a significant decrease was observed for neuron monocultures. Neurite elaboration into a neurite exclusive compartment in a compartmentalized microfluidic device, for both monocultures (no astrocytes) and "restricted" co-cultures (astrocytes touching neurites), decreased with exposure to increasing concentrations of m-DNB, but the average neurite area was higher in co-cultures. By using co-culture systems that more closely approach biological and architectural complexities, and the directionality of exposure found in the brain, this study provides a methodological foundation for unraveling the role of physical contact between astrocytes and neurons in mitigating the toxic effects of chemicals such as m-DNB.
authors.affiliation: Toxicology Program, School of Public Health, University of Michigan, Ann Arbor, MI 48109, United States. Electronic address: dixangel@umich.edu.
authors.forename: Angela R
authors.initials: AR
authors.lastname: Dixon
authors.affiliation: Toxicology Program, School of Public Health, University of Michigan, Ann Arbor, MI 48109, United States. Electronic address: philbert@umich.edu.
authors.forename: Martin A
authors.initials: MA
authors.lastname: Philbert
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000187:drug effects*; D001369:Axons / Q000187:drug effects; D002540:Cerebral Cortex / Q000166:cytology* / Q000196:embryology; D018920:Coculture Techniques; D004136:Dinitrobenzenes / Q000633:toxicity*; D007150:Immunohistochemistry; D046210:Microfluidic Analytical Techniques; D009410:Nerve Degeneration / Q000139:chemically induced* / Q000473:pathology; D016501:Neurites / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D051381:Rats
chemical_list: D004136:Dinitrobenzenes; C017906:3-dinitrobenzene
keywords: Co-culture; Cortical astrocytes; Cortical neurons; Microfluidic; Morphology; m-Dinitrobezene (m-DNB)