Contents lists available at ScienceDirect Experimental Gerontology journal homepage: www.elsevier.com/locate/expgero Early impairment of epigenetic pattern in neurodegeneration: Additional mechanisms behind pyrethroid toxicity Laura Bordoni a , Cinzia Nasuti a , Donatella Fedeli a , Roberta Galeazzi b , Emiliano Laudadio b , Luca Massaccesi b , Gerardo López-Rodas c , Rosita Gabbianelli a, ⁎ a School of Pharmacy, University of Camerino, Camerino 62032, MC, Italy b Department of Life and Environmental Sciences, Polytechnic University of Marche, 60128, AN, Italy c Department of Biochemistry and Molecular Biology, University of Valencia and INCLIVA Biomedical Research Institute, Valencia, Spain ARTICLE INFO Section Editor: Christian Humpel Keywords: Early-life Rats Permethrin-pesticide Epigenetics Neurodegeneration In silico ABSTRACT Permethrin is a synthetic pyrethroid extensively used as anti-woodworm agent and for indoor and outdoor pest control. The main route of human exposure is through fruit, vegetable and milk intake. Low dosage exposure to permethrin during neonatal brain development (from postnatal day 6 to postnatal day 21) leads to dopamine decrease in rat striatum nucleus, oxidative stress and behavioural changes linked to the development of Parkinson's like neurodegeneration later in life. The aim of this study was to evaluate the expression of genes involved in the dopaminergic pathway and epigenetic regulatory mechanisms in adolescent rats treated with permethrin during neonatal brain develop- ment. Furthermore, in order to shed light on the mechanisms associated with molecular impairments, in silico studies were performed. The outcomes show increased expression of genes related to the dopamine-synthesis pathway (Nurr1, Th, Snca), epigenetics (TET proteins and Mecp2) and exposure to toxicants (Pon1 and Pon2) in adolescent rats compared with control group. Furthermore, increased global 5mC and 5hmC levels were observed in the DNA extracted from striatum of early-life treated rats in comparison with controls. FAIRE-qPCR analysis shows that permethrin induces an enrichment of chromatin-free DNA at the level of Th and Nurr1 promoters, and ChIP- qPCR reveals a significant reduction in methylation levels at H3K9me3 position at both Th and Nurr1 promoter regions. In silico studies show that permethrin competes for the same two binding sites of known NURR1 agonists, with a lower binding free energy for permethrin, suggesting an important durable association of permethrin with the orphan receptor. Moreover, alpha-synuclein shows a strong affinity for NURR1, corroborating previous experimental outcomes on the interactions between them. This study focuses on an emerging role of early-life exposure to environmental pollutants in the regulation of late onset diseases through intriguing mechanisms that change crucial epigenetic patterns starting from ado- lescent age. https://doi.org/10.1016/j.exger.2019.06.002 Received 18 January 2019; Received in revised form 3 June 2019; Accepted 3 June 2019 Abbreviations: PERM, Permethrin; 5mC, 5-methylcytosine; 5hmC, 5-hydroxymethylcytosine; TET, Ten-eleven translocation; MeCP2, Methyl-CpG-binding protein; NOAEL, No Observed Adverse Effect Level; PD, Parkinson's disease; PND, Post Natal Day; GSH, Glutathione; GPx, Glutathione peroxidase; CAT, Catalase; SOD, Superoxide dismutase; FAIRE, Formaldehyde-assisted isolation of regulatory elements; aa, aminoacids; PES, Potential Energy Surface; DFT, Density Functional Theory; MD, Molecular Dynamics; RMSD, Root Mean Square Deviation; MM-PBSA, molecular mechanics Poisson-Boltzmann surface area; GB/SA, Generalized Born/ Solvent Accessible Surface model; PDB, Protein Brookhaven Data Bank; LBD, Ligand Binding Domain; NRs, Nuclear Receptors; DNMTs, DNA methyl-transferases; PAR, Predictive Adaptive Response; DOHaD, Developmental Origin of Health and Disease; CREB, cAMP response element-binding protein; PD, Parkinson's-like disease ⁎ Corresponding author. E-mail addresses: laura.bordoni@unicam.it (L. Bordoni), cinzia.nasuti@unicam.it (C. Nasuti), donatella.fedeli@unicam.it (D. Fedeli), r.galeazzi@staff.univpm.it (R. Galeazzi), e.laudadio@staff.univpm.it (E. Laudadio), l.massaccesi@staff.univpm.it (L. Massaccesi), gerardo.lopez@uv.es (G. López-Rodas), rosita.gabbianelli@unicam.it (R. Gabbianelli). Experimental Gerontology 124 (2019) 110629 Available online 05 June 2019 0531-5565/ © 2019 Elsevier Inc. All rights reserved. T