title: Inhibition of histone deacetylase reduces transcription of NADPH oxidases and ROS production and ameliorates pulmonary arterial hypertension.
abstract: Excessive levels of reactive oxygen species (ROS) and increased expression of NADPH oxidases (Nox) have been proposed to contribute to pulmonary artery hypertension (PAH) and other cardiovascular diseases (CVD). Nox enzymes are major sources of ROS but the mechanisms regulating changes in Nox expression in disease states remain poorly understood. Epigenetics encompasses a number of mechanisms that cells employ to regulate the ability to read and transcribe DNA. Histone acetylation is a prominent example of an epigenetic mechanism regulating the expression of numerous genes by altering chromatin accessibility. The goal of this study was to determine whether inhibition of histone deacetylases (HDAC) affects the expression of Nox isoforms and reduces pulmonary hypertension. In immune cells, we found that multiple HDAC inhibitors robustly decreased Nox2 mRNA and protein expression in a dose-dependent manner concomitant with reduced superoxide production. This effect was not restricted to Nox2 as expression of Nox1, Nox4 and Nox5 was also reduced by HDAC inhibition. Surprisingly, Nox promoter-luciferase activity was unchanged in the presence of HDAC inhibitors. In macrophages and lung fibroblasts, ChIP experiments revealed that HDAC inhibitors block the binding of RNA polymerase II and the histone acetyltransferase p300 to the Nox2, Nox4 and Nox5 promoter regions and decrease histones activation marks (H3K4me3 and H3K9ac) at these promoter sites. We further show that the ability of CRISPR-ON to drive transcription of Nox1, Nox2, Nox4 and Nox5 genes is blocked by HDAC inhibitors. In a monocrotaline (MCT) rat model of PAH, multiple HDAC isoforms are upregulated in isolated pulmonary arteries, and HDAC inhibitors attenuate Nox expression in isolated pulmonary arteries and reduce indices of PAH. In conclusion, HDAC inhibitors potently suppress Nox gene expression both in vitro and in vivo via epigenetically regulating chromatin accessibility.
authors: Department of Forensic Medicine, Nanjing Medical University, Nanjing, Jiangsu 210029 China; Vascular Biology Center, Augusta University, Augusta, GA 30912, USA. Electronic address: fchen@augusta.edu.
authors: Feng
authors: F
authors: Chen
authors: Vascular Biology Center, Augusta University, Augusta, GA 30912, USA.
authors: Xueyi
authors: X
authors: Li
authors: Vascular Biology Center, Augusta University, Augusta, GA 30912, USA.
authors: Emily
authors: E
authors: Aquadro
authors: Vascular Biology Center, Augusta University, Augusta, GA 30912, USA.
authors: Stephen
authors: S
authors: Haigh
authors: Department of Pharmacology, Augusta University, Augusta, GA 30912, USA.
authors: Jiliang
authors: J
authors: Zhou
authors: Vascular Biology Center, Augusta University, Augusta, GA 30912, USA.
authors: David W
authors: DW
authors: Stepp
authors: Vascular Biology Center, Augusta University, Augusta, GA 30912, USA; Department of Medicine, Augusta University, Augusta, GA 30912, USA.
authors: Neal L
authors: NL
authors: Weintraub
authors: Department of Pharmacology, Augusta University, Augusta, GA 30912, USA.
authors: Scott A
authors: SA
authors: Barman
authors: Vascular Biology Center, Augusta University, Augusta, GA 30912, USA; Department of Pharmacology, Augusta University, Augusta, GA 30912, USA. Electronic address: dfulton@augusta.edu.
authors: David J R
authors: DJR
authors: Fulton
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D002460:Cell Line; D042783:Endothelial Cells; D044127:Epigenesis, Genetic; D005347:Fibroblasts; D017930:Genes, Reporter; D057809:HEK293 Cells; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology*; D006655:Histone Deacetylases / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D006976:Hypertension, Pulmonary / Q000139:chemically induced / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D016686:Monocrotaline; D000074662:NADPH Oxidase 2 / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012319:RNA Polymerase II / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors / Q000378:metabolism; D015398:Signal Transduction; D014158:Transcription, Genetic / Q000187:drug effects*; D050880:p300-CBP Transcription Factors / Q000235:genetics / Q000378:metabolism; D000099224:p300-CBP-Associated Factor
chemical_list: D000959:Antihypertensive Agents; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases; D007527:Isoenzymes; D008156:Luciferases; D016686:Monocrotaline; D000074662:NADPH Oxidase 2; D012319:RNA Polymerase II; D017382:Reactive Oxygen Species; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor; C500593:Cybb protein, rat
keywords: Epigenetics; Histone deacetylases; NADPH oxidase; Pulmonary artery hypertension