title: Histone Deacetylase 5 Is Overexpressed in Scleroderma Endothelial Cells and Impairs Angiogenesis via Repression of Proangiogenic Factors.
abstract: Vascular dysfunction represents a disease-initiating event in systemic sclerosis (SSc; scleroderma). Results of recent studies suggest that epigenetic dysregulation impairs normal angiogenesis and can result in abnormal patterns of blood vessel growth. Histone deacetylases (HDACs) control endothelial cell (EC) proliferation and regulate EC migration. Specifically, HDAC-5 appears to be antiangiogenic. This study was undertaken to test whether HDAC-5 contributes to impaired angiogenesis in SSc by repressing proangiogenic factors in ECs.
  
  
  
  Dermal ECs were isolated from patients with diffuse cutaneous SSc and healthy controls. Angiogenesis was assessed using an in vitro Matrigel tube formation assay. An assay for transposase-accessible chromatin using sequencing (ATAC-seq) was performed to assess and localize the genome-wide effects of HDAC5 knockdown on chromatin accessibility.
  
  
  
  The expression of HDAC5 was significantly increased in ECs from patients with SSc compared to healthy control ECs. Silencing of HDAC5 in SSc ECs restored normal angiogenesis. HDAC5 knockdown followed by ATAC-seq assay in SSc ECs identified key HDAC5-regulated genes involved in angiogenesis and fibrosis, such as CYR61, PVRL2, and FSTL1. Simultaneous knockdown of HDAC5 in conjunction with either CYR61, PVRL2, or FSTL1 inhibited angiogenesis in SSc ECs. Conversely, overexpression of these genes individually led to an increase in tube formation as assessed by Matrigel assay, suggesting that these genes play functional roles in the impairment of angiogenesis in SSc.
  
  
  
  Several novel HDAC5-regulated target genes associated with impaired angiogenesis were identified in SSc ECs by ATAC-seq. The results of this study provide a potential link between epigenetic regulation and impaired angiogenesis in SSc, and identify a novel mechanism for the dysregulated angiogenesis that characterizes this disease.
authors.affiliation: University of Michigan, Ann Arbor.
authors.forename: Pei-Suen
authors.initials: PS
authors.lastname: Tsou
authors.affiliation: Oklahoma Medical Research Foundation and University of Oklahoma Health Sciences Center, Oklahoma City.
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Wren
authors.affiliation: University of Michigan, Ann Arbor.
authors.forename: M Asif
authors.initials: MA
authors.lastname: Amin
authors.affiliation: University of Michigan, Ann Arbor.
authors.forename: Elena
authors.initials: E
authors.lastname: Schiopu
authors.affiliation: University of Michigan, Ann Arbor.
authors.forename: David A
authors.initials: DA
authors.lastname: Fox
authors.affiliation: University of Michigan, Ann Arbor.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Khanna
authors.affiliation: University of Michigan, Ann Arbor.
authors.forename: Amr H
authors.initials: AH
authors.lastname: Sawalha
mesh_terms: D000328:Adult; D015153:Blotting, Western; D015815:Cell Adhesion Molecules / Q000235:genetics; D002478:Cells, Cultured; D055515:Cysteine-Rich Protein 61 / Q000235:genetics; D015536:Down-Regulation; D042783:Endothelial Cells / Q000378:metabolism* / Q000502:physiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D038702:Follistatin-Related Proteins / Q000235:genetics; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D006655:Histone Deacetylases / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D000075983:Nectins; D018919:Neovascularization, Physiologic / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D045743:Scleroderma, Diffuse / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology; D012867:Skin / Q000098:blood supply; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: C501848:CCN1 protein, human; D015815:Cell Adhesion Molecules; D055515:Cysteine-Rich Protein 61; D038702:Follistatin-Related Proteins; D000075983:Nectins; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D016222:Fibroblast Growth Factor 2; C448799:FSTL1 protein, human; C404500:HDAC5 protein, human; D006655:Histone Deacetylases