TY - JOUR T1 - Heterocyclic Thioureylenes Protect from Calcium-Dependent Neuronal Cell Death JF - Molecular Pharmacology JO - Mol Pharmacol SP - 667 LP - 676 DO - 10.1124/mol.108.052183 VL - 75 IS - 3 AU - Matjaz Humar AU - Christine Graetz AU - Martin Roesslein AU - Ulrich Goebel AU - Klaus K. Geiger AU - Bernd Heimrich AU - Benedikt H. J. Pannen Y1 - 2009/03/01 UR - http://molpharm.aspetjournals.org/content/75/3/667.abstract N2 - Calcium-dependent cell death occurs in neurodegenerative diseases and ischemic or traumatic brain injury. We analyzed whether thioureylenes can act in a neuroprotective manner by pharmacological suppression of calcium-dependent pathological pathways. In human neuroblastoma (SK-N-SH) cells, thioureylenes (thiopental, carbimazole) inhibited the calcium-dependent neuronal protein phosphatase (PP)-2B, the activation of the proapoptotic transcription factor nuclear factor of activated T-cells, BAD-induced initiation of caspase-3, and poly-(ADP-ribose)-polymerase cleavage. Caspase-3-independent cell death was attenuated by carbimazole and the protein kinase C (PKC) δ inhibitor rottlerin by a PP-2B-independent mechanism. Neuroprotective effects were mediated by the redox-active sulfur of thioureylenes. Furthermore, we observed that the route of calcium mobilization was differentially linked to caspase-dependent or independent cell death and that BAD dephosphorylation did not necessarily induce intrinsic caspase activation. In addition, a new 30- to 35-kDa caspase-3 fragment with an unknown function was identified. In organotypic hippocampal slice cultures, thioureylenes inhibited caspase-3 activation or reduced N-methyl-d-aspartate and kainic acid receptor-mediated cell death that was independent of caspase-3. Because prolonged inhibition of caspase-3 resulted in caspase-independent cellular damage, different types of cell death must be taken under therapeutic consideration. Here we show that thioureylenes in combination with PKCδ inhibitors might represent a promising therapeutic approach to attenuate neuronal damage. The American Society for Pharmacology and Experimental Therapeutics ER -