title: Epigenetically modified nucleotides in chronic heroin and cocaine treated mice.
abstract: Epigenetic changes include the addition of a methyl group to the 5' carbon of the cytosine ring, known as DNA methylation, which results in the generation of the fifth DNA base, namely 5-methylcytosine. During active or passive demethylation, an intermediate modified base is formed, 5-hydroxymethylcytosine. We have currently quantified 5-methylcytosine and 5-hydroxymethylcytosine in the liver and brain of mice treated with cocaine or heroin, using liquid chromatography/tandem mass spectrometry (LC-MS/MS). Our results show that global 5-methylcytosine levels are not affected by heroin or cocaine administration, neither in the liver nor in the brain. However, 5-hydroxymethylcytosine levels are reduced in the liver following cocaine administration, while they are not affected by cocaine in the brain or by heroin administration in the liver and the brain. Elucidation of the epigenetic phenomena that takes place with respect to drug abuse and addiction, via quantitative analysis of different modified bases, may enable a better understanding of the underlying mechanisms and may lead to more personalized and effective treatment options.
authors: Department of Occupational Safety and Health, Chung Shan Medical University, Taichung 402, Taiwan; Department of Occupational Medicine, Chung Shan Medical University Hospital, Taichung 402, Taiwan.
authors: Mu-Rong
authors: MR
authors: Chao
authors: Laboratory of Forensic Medicine and Toxicology, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.
authors: Domniki
authors: D
authors: Fragou
authors: Sleep, Chronobiology & Addiction Group, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK.
authors: Panos
authors: P
authors: Zanos
authors: Department of Public Health, Chung Shan Medical University, Taichung 402, Taiwan.
authors: Chiung-Wen
authors: CW
authors: Hu
authors: Sleep, Chronobiology & Addiction Group, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK.
authors: Alexis
authors: A
authors: Bailey
authors: Laboratory of Biological Chemistry, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.
authors: Sofia
authors: S
authors: Kouidou
authors: Laboratory of Forensic Medicine and Toxicology, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece. Electronic address: kovatsi@hotmail.com.
authors: Leda
authors: L
authors: Kovatsi
mesh_terms: D044503:5-Methylcytosine / Q000032:analysis* / Q000031:analogs & derivatives; D000818:Animals; D001921:Brain / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects; D003042:Cocaine / Q000633:toxicity*; D003596:Cytosine / Q000031:analogs & derivatives* / Q000032:analysis; D004305:Dose-Response Relationship, Drug; D044127:Epigenesis, Genetic / Q000187:drug effects*; D003932:Heroin / Q000633:toxicity*; D008099:Liver / Q000737:chemistry / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL
chemical_list: C011865:5-hydroxymethylcytosine; D044503:5-Methylcytosine; D003932:Heroin; D003596:Cytosine; D003042:Cocaine
keywords: 5-Hydroxymethylcytosine; 5-Methylcytosine; Addiction; Cocaine; Epigenetics; Heroin