Calcium signaling mechanisms disrupt the cytoskeleton of primary astrocytes and neurons exposed to diphenylditelluride

Background: Diphenylditelluride (PhTe)(2) is a potent neurotoxin disrupting the homeostasis of the cytoskeleton. Methods: Cultured astrocytes and neurons were incubated with ((PhTe)(2), receptor antagonists and enzyme inhibitors followed by measurement of the incorporation of [32P]orthophosphate into intermediate filaments (IFs). Results: ((PhTe)(2) caused hyperphosphorylation of glial fibrillary acidic protein (GFAP), vimentin and neurofilament subunits (NFL, NFM and NFH) from primary astrocytes and neurons, respectively. These mechanisms were mediated by N-methyl-D-aspartate (NMDA) receptors, L-type voltage-dependent calcium channels (L-VDCCs) as well as metabotropic glutamate receptors upstream of phospholipase C (PLC). Upregulated Ca2+ influx activated protein kinase A (PKA) and protein kinase C (PKC) in astrocytes causing hyperphosphorylation of GFAP and vimentin. Hyperphosphorylated (IF) together with RhoA-activated stress fiber formation, disrupted the cytoskeleton leading to altered cell morphology. In neurons, the high intracellular Ca2+ levels activated the MAPKs, Erk and p38MAPK, beyond PKA and PKC, provoking hyperphosphorylation of NFM, NFH and NFL. Conclusions: Our findings support that intracellular Ca2+ is one of the crucial signals that modulate the action of ((PhTe)(2) in isolated cortical astrocytes and neurons modulating the response of the cytoskeleton against the insult. General significance: Cytoskeletal misregulation is associated with neurodegeneration. This compound could be a valuable tool to induce molecular changes similar to those found in different pathologies of the brain. (C) 2016 Elsevier B.V. All rights reserved.