Role of RASEF hypermethylation in cigarette smoke-induced pulmonary arterial smooth muscle remodeling

Abstract

Background Pulmonary hypertension (PH) is a progressive and fatal disease. While cigarette smoke can change DNA methylation status, the role of such molecular alterations in smoke-associated PH is unclear. Methods A PH rat model was developed by exposing animals to cigarette smoke for 3 months. Right ventricular systolic pressure was measured with a right heart catheter. Histological changes (right ventricular hypertrophy index, medial wall thickness in pulmonary arteries (PAs)) and DNMT1 protein levels in rat PAs or primary human PA smooth muscle cells (HPASMCs) exposed to cigarette smoke extract were assessed. Methylation sequencing and MassArray® were used to detect genomic and RASEF promoter methylation status, respectively. After DNMT1 knockdown and cigarette smoke extract exposure, HPASMCs behavior (proliferation, migration) and RASEF methylation status were examined; RASEF mRNA expression was evaluated by real-time-polymerase chain reaction. RASEF overexpression viral vectors were used to assess the impact of RASEF on rat PH and HPASMCs remodeling. Results Higher right ventricular systolic pressure, medial wall thickness, and right ventricular hypertrophy index values were observed in the smoking group rats. Smoke exposure increased DNMT1 expression and RASEF methylation levels in rat PAs and HPASMCs. Cigarette smoke extract induced HPASMCs behavioral changes and RASEF hypermethylation followed by silencing, while DNMT1 knockdown markedly inhibited these changes. RASEF overexpression distinctly inhibited PH and HPASMCs remodeling, possibly through phospho-AKT (Ser473), PCNA, and MMP9 downregulation. Conclusions Cigarette smoke caused PA remodeling in PH rats related to RASEF hypermethylation. These results expand our understanding of key epigenetic mechanisms in cigarette smoke-associated PH and potentially provide a novel therapeutic target for PH. Electronic supplementary material The online version of this article (10.1186/s12931-019-1014-1) contains supplementary material, which is available to authorized users.

Protective effects of astragaloside IV against hypertension-induced vascular remodeling involves the DNMT1 and TET2 signaling pathway

“…DNMT1 has also been implicated in the pulmonary arterial remodeling in pulmonary hypertension. SD rats exposed to cigarette smoke developed pulmonary hypertension and exhibited upregulation of DNMT1 [11]. The current results demonstrated that an increased DNMT1 protein level was observed in rat aorta and VSMCs treated with Ang II.…”

“…Dysregulation of DNMT1 is associated with vascular diseases [9]. For example, a high-fat diet was shown to induce the expression of DNMT1 in rat aorta [10]; DNMT1 was upregulated in pulmonary smooth muscle cells in cigarette smoke-induced pulmonary hypertensive rats [11]. An increased DNMT1 expression level was found in VSMCs treated with homocysteine [12].…”

The preventive and therapeutic effects of AAV1‐KLF4‐shRNA in cigarette smoke‐induced pulmonary hypertension

“…The latter three groups were administrated by intratracheal injection of saline, AAV1 carrying control vector or AAV1 carrying the KLF4-shRNA as we described previously. 20 30 days after the intratracheal administration, the latter three groups underwent whole body exposure to CS for another 4 months.…”

“…In the prevention protocol, 44 rats were randomly assigned to one of four groups: sham (n = 8), saline (n = 12), AAV1‐control vector (n = 12) or AAV1‐KLF4‐shRNA (n = 12). The latter three groups were administrated by intratracheal injection of saline, AAV1 carrying control vector or AAV1 carrying the KLF4‐shRNA as we described previously 20 . 30 days after the intratracheal administration, the latter three groups underwent whole body exposure to CS for another 4 months.…”

Large Rab GTPases: Novel Membrane Trafficking Regulators with a Calcium Sensor and Functional Domains

“…Rab45/RASEF expression is regulated by promoter methylation of the Rab45/RASEF gene. Cigarette smoking induces DNA methylation in the promoter region of the Rab45/RASEF gene in arterial smooth muscle cells [54]. A mutation in the Rab45/RASEF promoter region causes methylation and low RASEF expression in uveal melanoma, suggesting that Rab45/RASEF acts as a tumor suppressor gene [48].…”