Resveratrol treatment reduces the vulnerability of SH-SY5Y cells and cortical neurons overexpressing SOD1-G93A to Thimerosal toxicity through SIRT1/DREAM/PDYN pathway

• Published in: Neurotoxicology (Park Forest South) 2019-03, Vol.71, p.6-15
• Main Authors: Laudati, Giusy, Mascolo, Luigi, Guida, Natascia, Sirabella, Rossana, Pizzorusso, Vincenzo, Bruzzaniti, Sara, Serani, Angelo, Di Renzo, Gianfranco, Canzoniero, Lorella M.T., Formisano, Luigi
• Format: Article
• Language: English
• Subjects: Alanine; Amyotrophic lateral sclerosis; Animals; Cell death; Cell Death - drug effects; Cell Line, Tumor; Cell survival; Cerebral Cortex - drug effects; Cerebral Cortex - metabolism; Copper; Deacetylation; DREAM; Enkephalins - metabolism; Exposure; Gene expression; Glycine; Humans; Immunoprecipitation; Kv Channel-Interacting Proteins - metabolism; Mercury; Mutation; Neurons; Neurons - drug effects; Neurons - metabolism; Neuroprotection; Neurotoxicity; Pollutants; Prodynorphin; Protein Precursors - metabolism; Proteins; Rats, Wistar; Reduction; Repressor Proteins - metabolism; Resveratrol; Resveratrol - administration & dosage; Signal Transduction; Signs and symptoms; siRNA; SIRT1 protein; Sirtuin 1 - metabolism; SOD1; Superoxide dismutase; Superoxide Dismutase - metabolism; Superoxide Dismutase-1 - metabolism; Survival; Thimerosal; Thimerosal - toxicity; Toxicity; Transfection; Zinc
• ISSN: 0161-813X; 1872-9711
• DOI: 10.1016/j.neuro.2018.11.009

[Display omitted] •Thimerosal, at non-toxic concentration, reduced cell survival in SOD1-G93 A cells.•Thimerosal induced neurotoxicity by activating the SIRT1/DREAM/PDYN pathway.•Resveratrol prevented Thimerosal-induced cell death. In humans, mutation of glycine 93 to alanine of Cu++/Zn++ superoxide dismutase type-1 (SOD1-G93 A) has been associated to some familial cases of Amyotrophic Lateral Sclerosis (ALS). Several evidence proposed the involvement of environmental pollutants that like mercury could accelerate ALS symptoms. SH-SY5Y cells stably transfected with SOD1 and G93 A mutant of SOD1 constructs were exposed to non-toxic concentrations (0.01 μM) of ethylmercury thiosalicylate (thimerosal) for 24 h. Interestingly, we found that thimerosal, in SOD1-G93 A cells, but not in SOD1 cells, reduced cell survival. Furthermore, thimerosal-induced cell death occurred in a concentration dependent-manner and was prevented by the Sirtuin 1 (SIRT1) activator Resveratrol (RSV). Moreover, thimerosal decreased the protein expression of transcription factor Downstream Regulatory Element Antagonist Modulator (DREAM), but not DREAM gene. Interestingly, DREAM reduction was blocked by co-treatment with RSV, suggesting the participation of SIRT1 in determining this effect. Immunoprecipitation experiments in SOD1-G93 A cells exposed to thimerosal demonstrated that RSV increased DREAM deacetylation and reduced its polyubiquitination. In addition, RSV counteracted thimerosal-enhanced prodynorphin (PDYN) mRNA, a DREAM target gene. Furthermore, cortical neurons transiently transfected with SOD1-G93 A construct and exposed to thimerosal (0.5 μM/24 h) showed a reduction of DREAM and an up-regulation of the prodynorphin gene. Importantly, both the treatment with RSV or the transfection of siRNA against prodynorphin significantly reduced thimerosal-induced neurotoxicity, while DREAM knocking-down potentiated thimerosal-reduced cell survival. These results demonstrate the particular vulnerability of SOD1-G93 A neuronal cells to thimerosal and that RSV via SIRT1 counteracts the neurodetrimental effect of this toxicant by preventing DREAM reduction and prodynorphin up-regulation.