Behavioral Sensitization Induced by Methamphetamine Causes Differential Alterations in Gene Expression and Histone Acetylation of the Prefrontal Cortex in Rats (Histone acetylation dataset)

Background: Methamphetamine (METH) is one of the most widely abused illicit substances worldwide; unfortunately, its addiction mechanism remains unclear. Based on accumulating evidence, changes in gene expression and chromatin modifications might be related to the persistent effects of METH on the brain. In the present study, we took advantage of METH-induced behavioral sensitization as an animal model that reflects some aspects of drug addiction and examined the changes in gene expression and histone acetylation in the prefrontal cortex (PFC) of adult rats. Methods: We conducted mRNA microarray and chromatin immunoprecipitation (ChIP) coupled to DNA microarray (ChIP-chip) analyses to screen and identify changes in transcript levels and histone acetylation patterns. Functional enrichment analyses, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, were performed to analyze the differentially expressed genes. We then further identified alterations in ANP32A (acidic leucine-rich nuclear phosphoprotein-32A) and POU3F2 (POU domain, class 3, transcription factor 2) using qPCR and ChIP-PCR assays. Results: In the rat model of METH-induced behavioral sensitization, METH challenge caused 275 differentially expressed genes and a number of hyperacetylated genes (821 genes with H3 acetylation and 10 genes with H4 acetylation). Based on mRNA microarray and GO and KEGG enrichment analyses, 24 genes may be involved in METH-induced behavioral sensitization, and 7 were confirmed using qPCR. We further examined the alterations in the levels of the ANP32A and POU3F2 transcripts and histone acetylation at different periods of METH-induced behavioral sensitization. H4 hyperacetylation contributed to the increased levels of ANP32A mRNA and H3/H4 hyperacetylation contributed to the increased levels of POU3F2 mRNA induced by METH challenge-induced behavioral sensitization, but not by acute METH exposure. Conclusions: The present results revealed alterations in transcription and histone acetylation in the rat PFC by METH exposure and provided evidence that modifications of histone acetylation contributed to the alterations in gene expression caused by METH-induced behavioral sensitization.背景：甲基苯丙胺（Methamphetamine, METH）是全球滥用范围最广的违禁精神活性物质之一，但其成瘾机制至今尚未阐明。现有研究证据表明，基因表达与染色质修饰的改变可能与甲基苯丙胺对大脑产生的持久效应密切相关。本研究以甲基苯丙胺诱导的行为敏化作为反映药物成瘾部分特征的动物模型，检测了成年大鼠前额叶皮层（prefrontal cortex, PFC）内的基因表达与组蛋白乙酰化变化。 方法：本研究采用mRNA芯片与染色质免疫共沉淀（chromatin immunoprecipitation, ChIP）联合DNA芯片（ChIP-chip）分析技术，筛选并鉴定转录水平与组蛋白乙酰化模式的改变。通过基因本体论（Gene Ontology, GO）、京都基因与基因组百科全书（Kyoto Encyclopedia of Genes and Genomes, KEGG）等功能富集分析方法，对差异表达基因进行富集分析。随后利用实时定量聚合酶链反应（quantitative polymerase chain reaction, qPCR）与染色质免疫共沉淀-聚合酶链反应（ChIP-PCR）实验，进一步验证了酸性亮氨酸富集核磷蛋白32A（acidic leucine-rich nuclear phosphoprotein-32A, ANP32A）与POU结构域3类转录因子2（POU domain, class 3, transcription factor 2, POU3F2）的表达变化。 结果：在甲基苯丙胺诱导的行为敏化大鼠模型中，甲基苯丙胺激发给药诱导了275个差异表达基因，以及大量高乙酰化基因（821个H3乙酰化基因与10个H4乙酰化基因）。结合mRNA芯片、GO与KEGG富集分析结果，共有24个基因可能参与甲基苯丙胺诱导的行为敏化过程，其中7个经qPCR验证。本研究进一步检测了甲基苯丙胺诱导行为敏化不同阶段中ANP32A、POU3F2的转录水平以及组蛋白乙酰化状态的改变。研究发现，由甲基苯丙胺激发给药诱导的行为敏化可通过H4高乙酰化提升ANP32A的mRNA水平，通过H3/H4高乙酰化提升POU3F2的mRNA水平，但急性甲基苯丙胺暴露并未产生此类效应。 结论：本研究结果揭示了甲基苯丙胺暴露可改变大鼠前额叶皮层的转录与组蛋白乙酰化状态，并证实组蛋白乙酰化修饰参与了甲基苯丙胺诱导行为敏化所导致的基因表达改变。