Zhou Z, Yuan Q, Mash DC, Goldman D. Substance-specific and shared transcription and epigenetic changes in the human hippocampus chronically exposed to cocaine and alcohol. Proceedings of the National Academy of Sciences USA 108: 6626

Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20849, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 04/2011; 108(16):6626-31. DOI: 10.1073/pnas.1018514108
Source: PubMed


The hippocampus is a key brain region involved in both short- and long-term memory processes and may play critical roles in drug-associated learning and addiction. Using whole genome sequencing of mRNA transcripts (RNA-Seq) and immunoprecipitation-enriched genomic DNA (ChIP-Seq) coupled with histone H3 lysine 4 trimethylation (H3K4me3), we found extensive hippocampal gene expression changes common to both cocaine-addicted and alcoholic individuals that may reflect neuronal adaptations common to both addictions. However, we also observed functional changes that were related only to long-term cocaine exposure, particularly the inhibition of mitochondrial inner membrane functions related to oxidative phosphorylation and energy metabolism, which has also been observed previously in neurodegenerative diseases. Cocaine- and alcohol-related histone H3K4me3 changes highly overlapped, but greater effects were detected under cocaine exposure. There was no direct correlation, however, between either cocaine- or alcohol-related histone H3k4me3 and gene expression changes at an individual gene level, indicating that transcriptional regulation as well as drug-related gene expression changes are outcomes of a complex gene-regulatory process that includes multifaceted histone modifications.

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