title: Histone deacetylase 4 promotes ubiquitin-dependent proteasomal degradation of Sp3 in SH-SY5Y cells treated with di(2-ethylhexyl)phthalate (DEHP), determining neuronal death.
abstract: Phthalates, phthalic acid esters, are widely used as plasticizers to produce polymeric materials in industrial production of plastics and daily consumable products. Animal studies have shown that di(2-ethylhexyl)phthalate (DEHP) may cause toxic effects in the rat brain. In the present study, chronic exposure to DEHP (0.1-100μM) caused dose-dependent cell death via the activation of caspase-3 in neuroblastoma cells. Intriguingly, this harmful effect was prevented by the pan-histone deacetylase (HDAC) inhibitor trichostatin A, by the class II HDAC inhibitor MC-1568, but not by the class I HDAC inhibitor MS-275. Furthermore, DEHP reduced specificity protein 3 (Sp3) gene expression, but not Sp3 mRNA, after 24 and 48h exposures. However, Sp3 protein reduction was prevented by pre-treatment with MC-1568, suggesting the involvement of class II HDACs in causing this effect. Then, we investigated the possible relationship between DEHP-induced neuronal death and the post-translational mechanisms responsible for the down-regulation of Sp3. Interestingly, DEHP-induced Sp3 reduction was associated to its deacetylation and polyubiquitination. Co-immunoprecipitation studies showed that Sp3 physically interacted with HDAC4 after DEHP exposure, while HDAC4 inhibition by antisense oligodeoxynucleotide reverted the DEHP-induced degradation of Sp3. Notably, Sp3 overexpression was able to counteract the detrimental effect induced by DEHP. Taken together, these results suggest that DEHP exerts its toxic effect by inducing deacetylation of Sp3 via HDAC4, and afterwards, Sp3-polyubiquitination.
authors: Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Via Pansini 5, 80131 Naples, Italy.
authors: Natascia
authors: N
authors: Guida
authors: Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Via Pansini 5, 80131 Naples, Italy.
authors: Giusy
authors: G
authors: Laudati
authors: Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), Napoli, Italy.
authors: Mario
authors: M
authors: Galgani
authors: Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), Napoli, Italy.
authors: Marianna
authors: M
authors: Santopaolo
authors: Department of Preventive Medical Sciences, University Federico II, Via Pansini 5, 80131 Naples, Italy.
authors: Paolo
authors: P
authors: Montuori
authors: Department of Preventive Medical Sciences, University Federico II, Via Pansini 5, 80131 Naples, Italy.
authors: Maria
authors: M
authors: Triassi
authors: Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Via Pansini 5, 80131 Naples, Italy.
authors: Gianfranco
authors: G
authors: Di Renzo
authors: Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Via Pansini 5, 80131 Naples, Italy; Division of Pharmacology, Department of Science and Technology, University of Sannio, Via Port'Arsa 11, 82100 Benevento, Italy. Electronic address: canzon@unisannio.it.
authors: Lorella M T
authors: LM
authors: Canzoniero
authors: Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Via Pansini 5, 80131 Naples, Italy; Division of Pharmacology, Department of Science and Technology, University of Sannio, Via Port'Arsa 11, 82100 Benevento, Italy. Electronic address: cformisa@unisannio.it.
authors: Luigi
authors: L
authors: Formisano
mesh_terms: D000818:Animals; D016923:Cell Death / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D004051:Diethylhexyl Phthalate / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology; D006655:Histone Deacetylases / Q000378:metabolism*; D006801:Humans; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012097:Repressor Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D025801:Ubiquitin / Q000378:metabolism*
chemical_list: D056572:Histone Deacetylase Inhibitors; D012097:Repressor Proteins; D025801:Ubiquitin; D004051:Diethylhexyl Phthalate; D046988:Proteasome Endopeptidase Complex; C400300:HDAC4 protein, human; D006655:Histone Deacetylases
keywords: Acetylation; DEHP; HDAC4; MC-1568; Ubiquitination