Linked Life Data

19592460

Source:http://linkedlifedata.com/resource/pubmed/id/19592460

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2009-9-28
pubmed:abstractText
Angiotensin-converting enzyme (ACE) enhances the proliferation and migration of pulmonary artery smooth muscle cells (PASMCs), which contribute to the pathogenesis of hypoxic pulmonary hypertension (HPH). Previous reports have demonstrated that hypoxia upregulates ACE expression, but the underlying mechanism is unknown. Here, we found that ACE is persistently upregulated in PASMCs on the transcriptional level during hypoxia. Hypoxia-inducible factor 1alpha (HIF-1alpha), a key transcription factor activated during hypoxia, was able to upregulate ACE protein expression under normoxia, whereas knockdown of HIF-1alpha expression in PASMCs inhibited hypoxia-induced ACE upregulation. Furthermore, HIF-1alpha can bind and transactivate the ACE promoter directly. Therefore, we report that ACE is a novel target of HIF-1alpha. Recently, a homolog of ACE, ACE2, was reported to counterbalance the function of ACE. In contrast to ACE, we found that ACE2 mRNA and protein levels increased during the early stages of hypoxia and decreased to near-baseline levels at the later stages after HIF-1alpha accumulation. Thus HIF-1alpha inhibited ACE2 expression, and the accumulated ANG II catalyzed by ACE is a key mediator in the downregulation of ACE2 by HIF-1alpha. Moreover, a reduction of ACE2 expression in PASMCs by RNA interference was accompanied by significantly enhanced proliferation and migration during hypoxia. We conclude that ACE is directly regulated by HIF-1alpha, whereas ACE2 is regulated in a bidirectional way during hypoxia and may play a protective role during the development of HPH. In sum, these findings contribute to the understanding of the pathogenesis of HPH.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1522-1504
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
297
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
L631-40
pubmed:meshHeading
pubmed-meshheading:19592460-Angiotensin II, pubmed-meshheading:19592460-Anoxia, pubmed-meshheading:19592460-Blotting, Western, pubmed-meshheading:19592460-Cell Movement, pubmed-meshheading:19592460-Cell Proliferation, pubmed-meshheading:19592460-Cells, Cultured, pubmed-meshheading:19592460-Chromatin Immunoprecipitation, pubmed-meshheading:19592460-Fluorescent Antibody Technique, pubmed-meshheading:19592460-Humans, pubmed-meshheading:19592460-Hypertension, Pulmonary, pubmed-meshheading:19592460-Hypoxia-Inducible Factor 1, alpha Subunit, pubmed-meshheading:19592460-Muscle, Smooth, Vascular, pubmed-meshheading:19592460-Myocytes, Smooth Muscle, pubmed-meshheading:19592460-Peptidyl-Dipeptidase A, pubmed-meshheading:19592460-Pulmonary Artery, pubmed-meshheading:19592460-RNA, Messenger, pubmed-meshheading:19592460-RNA, Small Interfering, pubmed-meshheading:19592460-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:19592460-Transcription, Genetic
pubmed:year
2009
pubmed:articleTitle
Role of HIF-1alpha in the regulation ACE and ACE2 expression in hypoxic human pulmonary artery smooth muscle cells.
pubmed:affiliation
Dept. of Respiratory Medicine, Ruijin Hospital, Medical School of Shanghai Jiaotong Univ., No. 197, Second Ruijin Rd., Shanghai 200025, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't