title: MS-275 inhibits aroclor 1254-induced SH-SY5Y neuronal cell toxicity by preventing the formation of the HDAC3/REST complex on the synapsin-1 promoter.
abstract: Polychlorinated biphenyl (PCB) exposure has been associated with neurodegenerative diseases, such as Parkinson's disease, amyotrophic lateral sclerosis, and dementia. Neuronal death elicited by the PCB mixture Aroclor 1254 (A1254) has been attributed to an increase in RE-1-silencing transcription factor (REST), which, in turn, correlates with a decrease in the synapsin-1 promoter gene. Although histone deacetylase (HDAC) inhibitors are known to be neuroprotective in several neurologic disorders, the core mechanisms governing this effect are not yet understood. Here, to examine how HDAC class I [N-(2-aminophenyl)-4-[N-(pyridin-3-yl-methoxycarbonyl)aminomethyl]-benzamide (MS-275)] and HDAC class II [3-[5-(3-(3-fluorophenyl)-3-oxopropen-1-yl)-1-methyl-1H-pyrrol-2-yl]-N-hydroxy-2-propenamide (MC-1568)] inhibitors prevent A1254-induced neuronal cell death, we exposed SH-SY5Y neuroblastoma cells to A1254. Exposure to A1254 (30.6 μM) for 24 and 48 hours resulted in a time-dependent cell death. Indeed, after 48 hours, MS-275, but not MC-1568, reverted A1254-induced cell death in a dose-dependent manner. Furthermore, A1254 significantly increased HDAC3, but not HDAC1 or HDAC2. Interestingly, REST physically interacted with HDAC3 after A1254 exposure. Chromatin immunoprecipitation assays revealed that MS-275 reverted the increased levels of HDAC3 binding and decreased acetylation of histone H3 within the synapsin-1 promoter region, thus reverting synapsin-1 mRNA reduction. Moreover, REST knockdown by small interfering RNA (siRNA) prevented HDAC3 from binding to the synapsin-1 promoter. Likewise, HDAC3 siRNA significantly reduced A1254-induced cell toxicity in SH-SY5Y cells and cortical neurons. Hence, this study demonstrates that inhibition of HDAC class I attenuates A1254-induced neuronal cell death by preventing HDAC3 binding and histone deacetylation within the synapsin-1 promoter region.
authors.affiliation: Division of Pharmacology, Department of Science and Technology, University of Sannio, Benevento, Italy (L.F., L.M.T.C.); and Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Naples, Italy (L.F., N.G., G.L., L.M., G.D.R., L.M.T.C.) cformisa@unisannio.it.
authors.forename: Luigi
authors.initials: L
authors.lastname: Formisano
authors.affiliation: Division of Pharmacology, Department of Science and Technology, University of Sannio, Benevento, Italy (L.F., L.M.T.C.); and Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Naples, Italy (L.F., N.G., G.L., L.M., G.D.R., L.M.T.C.).
authors.forename: Natascia
authors.initials: N
authors.lastname: Guida
authors.affiliation: Division of Pharmacology, Department of Science and Technology, University of Sannio, Benevento, Italy (L.F., L.M.T.C.); and Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Naples, Italy (L.F., N.G., G.L., L.M., G.D.R., L.M.T.C.).
authors.forename: Giusy
authors.initials: G
authors.lastname: Laudati
authors.affiliation: Division of Pharmacology, Department of Science and Technology, University of Sannio, Benevento, Italy (L.F., L.M.T.C.); and Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Naples, Italy (L.F., N.G., G.L., L.M., G.D.R., L.M.T.C.).
authors.forename: Luigi
authors.initials: L
authors.lastname: Mascolo
authors.affiliation: Division of Pharmacology, Department of Science and Technology, University of Sannio, Benevento, Italy (L.F., L.M.T.C.); and Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Naples, Italy (L.F., N.G., G.L., L.M., G.D.R., L.M.T.C.).
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Di Renzo
authors.affiliation: Division of Pharmacology, Department of Science and Technology, University of Sannio, Benevento, Italy (L.F., L.M.T.C.); and Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, "Federico II" University of Naples, Naples, Italy (L.F., N.G., G.L., L.M., G.D.R., L.M.T.C.).
authors.forename: Lorella M T
authors.initials: LM
authors.lastname: Canzoniero
mesh_terms: D000107:Acetylation; D001549:Benzamides / Q000494:pharmacology*; D015153:Blotting, Western; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D020111:Chlorodiphenyl (54% Chlorine) / Q000633:toxicity*; D047369:Chromatin Immunoprecipitation; D055785:Gene Knockdown Techniques; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology*; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D006801:Humans; D009474:Neurons / Q000187:drug effects*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011725:Pyridines / Q000494:pharmacology*; D034741:RNA, Small Interfering / Q000494:pharmacology; D060888:Real-Time Polymerase Chain Reaction; D012097:Repressor Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics; D016704:Synapsins / Q000235:genetics*; D000099229:RE1-Silencing Transcription Factor; D000099186:Histone Deacetylase 3
chemical_list: D001549:Benzamides; D020111:Chlorodiphenyl (54% Chlorine); D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases; D006657:Histones; D011725:Pyridines; D034741:RNA, Small Interfering; D012097:Repressor Proteins; D016704:Synapsins; D000099229:RE1-Silencing Transcription Factor; D000099186:Histone Deacetylase 3; C118739:entinostat