Effects of copper overload in P19 neurons: impairment of glutathione redox homeostasis and crosstalk between caspase and calpain protease systems in ROS-induced apoptosis

Autor: Maja Jazvinšćak Jembrek, Nada Oršolić, Vedrana Radovanović, Josipa Vlainić, Julija Erhardt
Rok vydání: 2014
Předmět:
Teratocarcinoma
Copper Sulfate
Nifedipine
Leupeptins
Apoptosis
General Biochemistry
Genetics and Molecular Biology
Biomaterials
chemistry.chemical_compound
Mice
Copper toxicity
P19 neurons
Glutathione
Lactate dehydrogenase
Calpain
ERK pathway
Adenosine Triphosphate
BAPTA
Cell Line
Tumor
medicine
Animals
Protease Inhibitors
RNA
Messenger
Protein Kinase Inhibitors
Caspase
Chelating Agents
chemistry.chemical_classification
Neurons
Reactive oxygen species
biology
Leupeptin
Metals and Alloys
medicine.disease
Chromatin
Cell biology
Neoplasm Proteins
Oxidative Stress
chemistry
Gene Expression Regulation
Caspases
biology.protein
Dizocilpine Maleate
Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating)
General Agricultural and Biological Sciences
Apoptosis Regulatory Proteins
Reactive Oxygen Species
Oxidation-Reduction
Signal Transduction
Zdroj: Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine. 27(6)
ISSN: 1572-8773
Popis: Copper, a transition metal with essential biological functions, exerts neurotoxic effects when present in excess. The aim of the present study was to better elucidate cellular and molecular mechanisms of CuSO4 toxicity in differentiated P19 neurons. Exposure to 0.5 mM CuSO4 for 24 h provoked moderate decrease in viability, accompanied with barely increased generation of reactive oxygen species (ROS) and caspase-3/7 activity. Glutathione (GSH) and ATP contents were depleted, lactate dehydrogenase inactivated, and glyceraldehyde-3-phosphate dehydrogenase overexpressed. In severely damaged neurons exposed to only two times higher concentration, classical caspase-dependent apoptosis was triggered as evidenced by marked caspase-3/7 activation and chromatin condensation. Multifold increase in ROS, together with very pronounced ATP and GSH loss, strongly suggests impairment of redox homeostasis. At higher copper concentration protease calpains were also activated, and neuronal injury was prevented in the presence of calpain inhibitor leupeptin through the mechanism that affects caspase activation. MK-801 and nifedipine, inhibitors of calcium entry, and H-89 and UO126, inhibitors of PKA and ERK signaling respectively, exacerbated neuronal death only in severely damaged neurons, while ROS-scavenger quercetin and calcium chelator BAPTA attenuated toxicity only at lower concentration. In a dose-dependent manner copper also provoked transcriptional changes of genes involved in intracellular signaling and induction of apoptosis (p53, c-fos, Bcl-2 and Bax). The obtained results emphasize differences in triggered neuronal-death processes in a very narrow range of concentrations and give further insight into the molecular mechanisms of copper toxicity with the potential to improve current therapeutic approaches in curing copper-related neurodegenerative diseases.
Databáze: OpenAIRE
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