Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.1.1.37 (DNA methyltransferase)
 4,983 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Phosphatase and tensin homolog (PTEN) plays an important role in the pathogenesis of hypoxic pulmonary hypertension (HPH). A decrease in PTEN expression is associated with the hypermethylation of its promoter. However, whether the demethylation of the PTEN gene could attenuate HPH remains unknown. 5-Aza-2'-deoxycytidine (5-Aza-dC) is a DNA methyltransferase (DNMT) inhibitor. The present study was designed to investigate the effects and mechanisms of 5-Aza-dC on HPH. The proliferation, migration and apoptosis of rat pulmonary artery smooth muscle cells (PASMCs) induced by hypoxia and treated with 5-Aza-dC were detected. The expression of PTEN and DNMTs and the PTEN methylation status of PASMCs were detected. SD rats were randomly divided into normal group, hypoxia group and hypoxia + 5-Aza-dC group. The expression of PTEN was decreased, the expression of DNMTs was increased, and the methylation status of PTEN was increased in hypoxia-induced PASMCs. However, 5-Aza-dC can rescue the decreased PTEN, inhibit DNMT levels in a dose-dependent manner and suppress PTEN methylation. Furthermore, the demethylation of PTEN, which was induced by 5-Aza-dC, inhibited the proliferation, migration and promoted apoptosis in PASMCs. In vivo studies further demonstrated that the expression of PTEN, mean pulmonary artery pressure and right ventricular hypertrophy index in HPH rats was attenuated by 5-Aza-dC. 5-Aza-dC also suppressed the expression of DNMTs and PTEN methylation in the lungs of HPH rats. These results indicated that PTEN promoter methylation status is involved in HPH. 5-Aza-dC, as a DNMT inhibitor, has the potential to attenuate HPH via demethylation of the PTEN promoter.
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PMID:5-Aza-2'-deoxycytidine, a DNA methylation inhibitor, attenuates hypoxic pulmonary hypertension via demethylation of the PTEN promoter. 3108 36

DNA methylation plays critical roles in vascular pathology of pulmonary hypertension (PH). The underlying mechanism, however, remains undetermined. Here, we demonstrate that global DNA methylation was elevated in the lungs of PH rat models after monocrotaline administration or hypobaric hypoxia exposure. We showed that DNA methyltransferase 3B (DNMT3B) was up-regulated in both PH patients and rodent models. Furthermore, Dnmt3b -/- rats exhibited more severe pulmonary vascular remodeling. Consistently, inhibition of DNMT3B promoted proliferation/migration of pulmonary artery smooth muscle cells (PASMCs) in response to platelet-derived growth factor-BB (PDGF-BB). In contrast, overexpressing DNMT3B in PASMCs attenuated PDGF-BB-induced proliferation/migration and ameliorated hypoxia-mediated PH and right ventricular hypertrophy in mice. We also showed that DNMT3B transcriptionally regulated inflammatory pathways. Our results reveal that DNMT3B is a previously undefined mediator in the pathogenesis of PH, which couples epigenetic regulations with vascular remodeling and represents a therapeutic target to tackle PH.
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PMID:DNA methyltransferase 3B deficiency unveils a new pathological mechanism of pulmonary hypertension. 3329 33