Role of histone deacetylases in regulation of phenotype of ovine newborn pulmonary arterial smooth muscle cells.
OBJECTIVE
Pulmonary arterial hypertension, characterized by pulmonary vascular remodelling and vasoconstriction, is associated with excessive proliferative changes in pulmonary vascular walls. However, the role of HDACs in the phenotypic alteration of pulmonary arterial smooth muscle cells (PASMC) is largely unknown.


METHODS
Pulmonary arterial smooth muscle cells were isolated from newborn sheep. Cell cycle analysis was performed by flow cytometry. mRNA and protein expression were measured by real-time PCR and Western blot analysis. Wound-healing scratch assay was used to measure cell migration. Contractility of newborn PASMCs was determined by gel contraction assay. Chromatin immunoprecipitation was used to examine histone modifications along the p21 promoter region. Global DNA methylation was measured by liquid chromatography-mass spectroscopy.


RESULTS
Inhibition of class I and class II HDACs by apicidin and HDACi VIII suppressed proliferation of newborn PASMC and induced cell cycle arrest in G1 phase. Acetyl H3 levels were higher in newborn PASMC treated with apicidin and HDACi VIII. This was accompanied by increased expression of p21 and reduced expression of CCND1 but not p53. HDAC inhibition altered histone codes around the p21 promoter region in NPASMC. Apicidin inhibited serum-induced cell migration, and modulated profiling of expression of genes encoding pro-oxidant and antioxidant enzymes. Contractility and global DNA methylation levels of newborn PASMCs were also markedly modulated by apicidin.


CONCLUSIONS
Our results demonstrate that class I HDACs are clearly involved in phenotypic alteration of newborn PASMC.
Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, 60612, USA.
Q
Q
Yang
M J
MJ
Dahl
K H
KH
Albertine
R
R
Ramchandran
M
M
Sun
J U
JU
Raj
D000107:Acetylation / Q000187:drug effects; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D059447:Cell Cycle Checkpoints / Q000187:drug effects / Q000235:genetics; D002465:Cell Movement / Q000187:drug effects / Q000235:genetics; D049109:Cell Proliferation / Q000187:drug effects; D019938:Cyclin D1 / Q000235:genetics / Q000378:metabolism; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism; D019175:DNA Methylation / Q000187:drug effects / Q000235:genetics; D065627:Familial Primary Pulmonary Hypertension; D016193:G1 Phase / Q000187:drug effects / Q000235:genetics; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism*; D006657:Histones / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006976:Hypertension, Pulmonary / Q000235:genetics / Q000378:metabolism; D007231:Infant, Newborn; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism*; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D010641:Phenotype; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000235:genetics; D011651:Pulmonary Artery / Q000187:drug effects / Q000378:metabolism*; D012756:Sheep; D059467:Transcriptome / Q000187:drug effects / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
D000975:Antioxidants; D050759:Cyclin-Dependent Kinase Inhibitor p21; D056572:Histone Deacetylase Inhibitors; D006657:Histones; D016159:Tumor Suppressor Protein p53; D019938:Cyclin D1; D006655:Histone Deacetylases