A decrease of intracellular ATP is compensated by increased respiration and acidification at sub-lethal parathion concentrations in murine embryonic neuronal cells: Measurements in metabolic cell-culture chips

• Published in: Toxicology letters Vol. 207; no. 2; pp. 182 - 190
• Main Authors: Buehler, S.M., Stubbe, M., Gimsa, U., Baumann, W., Gimsa, J.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 30-11-2011; Elsevier
• Subjects: Adenosine Triphosphate - analysis; Adenosine Triphosphate - physiology; Animal experiment replacement; Animals; ATP; Biological and medical sciences; Cell Adhesion - drug effects; Cell Respiration - drug effects; Dose-Response Relationship, Drug; Hormesis; Lab-On-A-Chip Devices; Lab-on-chip system; Medical sciences; Metabolism; Mice - embryology; Microelectrodes; Neurons - chemistry; Neurons - drug effects; Neurons - metabolism; Neurotoxicity; Non-invasive online monitoring; Parathion - toxicity; Pesticides, fertilizers and other agrochemicals toxicology; Toxicity Tests - instrumentation; Toxicity Tests - methods; Toxicology; DMEM; SD; Neurotoxicity; P/S; FBS; MC; Animal experiment replacement; IC50; PDL; SM; Non-invasive online monitoring; Hormesis; ISFET; MM; PBS; AChE; CM; IDES; Metabolism; ES; MEPC; DIV; Lab-on-chip system; MMT; GABA; Parathion; Cell culture; Insecticide; Toxicity; Acidification; Quantitative analysis; Nervous system diseases; Pesticides; Rodentia; System on a chip; In vitro; Vertebrata; Lethal concentration; Sublethal dose; Mammalia; Neuron; Decrease; Mouse; Surveillance; Embryonic cell; Animal; Non invasive method; Alternative method; Organophosphorus compounds; Intracellular; Respiration; ATP
• ISSN: 0378-4274; 1879-3169
• DOI: 10.1016/j.toxlet.2011.09.005

► In vitro test strategy for cell-metabolic effects of toxins with murine embryonic, primary cortex cells (MEPCs). ► Cell-chips were used for the on-line registration of the parathion effect on respiration, acidification and cell adhesion. ► IC50 values were 100μM (respiration), 65μM (acidification), 54μM (adhesion), and 33μM (intracellular ATP-level). ► While ATP-level and cell adhesion showed a simple logistic decay, respiration and acidification were increased at low doses. ► This is a result of cellular regulation induced by the uncoupling of cellular respiration by parathion and its metabolites.
We present a label-free in vitro method for testing the toxic potentials of chemical substances using primary neuronal cells. The cells were prepared from 16-day-old NMRI mouse embryos and cultured on silicon chips (www.bionas.de) under the influence of different parathion concentrations with sensors for respiration (Clark-type oxygen electrodes), acidification (pH-ISFETs) and cell adhesion (interdigitated electrode structures, IDES). After 12 days in vitro, the sensor readouts were simultaneously recorded for 350min in the presence of parathion applying a serial 1:3 dilution. The parathion-dependent data was fitted by logistic functions. IC50 values of approximately 105μM, 65μM, and 54μM were found for respiration, acidification, and adhesion, respectively. An IC50 value of approximately 36μM was determined from the intracellular ATP-levels of cells, which were detected by an ATP-luminescence assay using micro-well plates. While the intracellular ATP level and cell adhesion showed no deviation from a simple logistic decay, increases of approximately 29% in the respiration and 15% in the acidification rates above the control values were found at low parathion concentrations, indicating hormesis. These increases could be fitted by a modified logistic function. We believe that the label-free, continuous, multi-parametric monitoring of cell-metabolic processes may have applications in systems-biology and biomedical research, as well as in environmental monitoring. The parallel characterization of IC50 values and hormetic effects may provide new insights into the metabolic mechanisms of toxic challenges to the cell.