Silencing EIF3A ameliorates pulmonary arterial hypertension through HDAC1 and PTEN/PI3K/AKT pathway in vitro and in vivo.

Pulmonary vascular remodeling caused by the excessive proliferation of pulmonary arterial smooth muscle cells (PASMCs) is the hallmark feature of pulmonary arterial hypertension (PAH). Eukaryotic initiation factor 3 subunit A (EIF3A) exhibited proliferative activity in multiple cell types. The present study investigated the role of EIF3A in the progression of PAH. A monocrotaline (MCT)-induced PAH rat model was constructed, and adeno-associated virus type 1 (AAV1) carrying EIF3A shRNA was intratracheally delivered to PAH rats to block EIF3A expression. PASMCs were isolated from rats and treated with PDGF-BB to simulate PASMC proliferation, and shRNA for EIF3 was conducted to investigate the mechanism behind the role of EIF3A in PASMC function in vitro. EIF3A expression was upregulated in pulmonary arteries, and EIF3A inhibition effectively improved pulmonary hypertension and right ventricular hypertrophy and suppressed MCT-induced vascular remodeling in vivo. In addition, we found that genetic knockdown of EIF3A reduced PDGF-triggered proliferation and arrested cell cycle, accompanied by downregulated proliferation-related protein expression in PASMCs. Mechanistically, the histone deacetylase 1 (HDAC1)-mediated PTEN/PI3K/AKT pathway was recognized as a primary mechanism in PAH progression. Silencing EIF3A decreased HDAC1 expression, and further inhibited the excessive proliferation of PASMCs by increasing the phosphatase and tension homolog (PTEN) expression and suppressing the AKT phosphorylation. Notably, HDAC1 expression reversed the effect of silencing EIF3A on PAH and PTEN/PI3K/AKT pathway. Collectively, silencing EIF3A improved PAH by decreasing PASMC proliferation through the HDAC1-mediated PTEN/PI3K/AKT pathway. These findings suggest that targeting EIF3A may represent a potential approach for the treatment of PAH.

Yang HT ，Wang G ，Zhu PC ，Xiao ZY ... -  《-》

A modified Fangji Huangqi decoction ameliorates pulmonary artery hypertension via phosphatidylinositide 3-kinases/protein kinase B-mediated regulation of proliferation and apoptosis of smooth muscle cells in vitro and in vivo.

Pulmonary artery hypertension (PAH) is a progressive and fatal lung disease of multifactorial etiology, which arouses an enhanced interest in PAH disease therapy. Modified Fangji Huangqi decoction (MFJHQ), a traditional Chinese medicine (TCM) formula, has a crucial role in the treatment of PAH. However, the pharmacological roles and mechanisms of MFJHQ on PAH remain unknown. To investigate the effects and potential mechanism of MFJHQ on pulmonary vascular remodeling in PAH. Ultra-performance liquid chromatography (UPLC) was employed to quantitate the principal components in MFJHQ. Rats were treated with MFJHQ by gavage for final 2 weeks in monocrotaline (MCT)-induced PAH rats. RNA-sequencing and network pharmacology analysis were performed to explore the potential mechanism. The primary rat pulmonary artery smooth muscle cells (PASMCs) were utilized to evaluate the regulatory effect of MFJHQ in vitro. Seven active components from MFJHQ were quantitated by UPLC. In rats with MCT-induced PAH, MFJHQ treatment significantly improved hemodynamic parameters, right ventricular hypertrophy index, lung function, and attenuated pulmonary vascular remodeling. Mechanistically, we further confirmed that MFJHQ inhibits MCT-induced phosphatidylinositide 3-kinases/protein kinase B (PI3K/Akt) pathway predicated by network pharmacology and RNA-sequencing analysis to reduce the proliferation of pulmonary arteries and promote pulmonary artery apoptosis in lung tissues. Additionally, MFJHQ hindered the proliferation and migration, and accelerated apoptosis in PDGF-BB-induced PASMCs in vitro, which can be enhanced by the presence of the PI3K inhibitor LY294002. Our results indicated that MFJHQ inhibited MCT-induced pulmonary vascular remodeling by decreasing proliferation and migration of PASMCs and promoting PASMC apoptosis through PI3K/Akt pathway, which provides a novel treatment option for PAH with multi-targeting mechanisms inspired by TCM theory.

Xue Z ，Zhou M ，Liu Y ，Qin H ，Li Y ，Zhu Y ，Yang J ... -  《-》

Plasminogen activator Inhibitor-2 inhibits pulmonary arterial smooth muscle cell proliferation in pulmonary arterial hypertension via PI3K/Akt and ERK signaling.

The proliferation of pulmonary arterial smooth muscle cells (PASMCs) and subsequent pulmonary vascular remodeling leads to pulmonary arterial hypertension (PAH). Understanding the underlying mechanisms and identifying molecules that can suppress PASMCs proliferation is critical for developing effective pharmacological treatment. We previously showed that plasminogen activator inhibitor-2 (PAI-2) inhibited human PASMC (hPASMCs) proliferation in vitro. However, its inhibitory effect on PAH remains to be determined, and the mechanism remains to be illustrated. We compared serum PAI-2 levels between PAH patients and healthy controls, and examined the correlation between PAI-2 level and disease severity. In monocrotaline-induced PAH rats, we examined the effects of exogenous PAI-2 administration on pulmonary vascular remodeling and PAH development. The effect of PAI-2 and potential mechanisms was further examined in cultured hPASMCs. The serum PAI-2 was decreased in PAH patients compared with controls. PAI-2 level was negatively correlated with mean pulmonary arterial pressure and estimated systolic pulmonary arterial pressure in ultrasonic cardiogram, while positively correlated with 6-min walking distance. In rats, administration of exogenous PAI-2 significantly reversed monocrotaline-induced PAH, as indicated by the decrease in right ventricle systolic pressure, right ventricular hypertrophy index and percent media thickness of pulmonary arterioles. Further mechanistic investigation in hPASMCs showed that PAI-2 inhibited cell proliferation by preventing the activation of PI3K/Akt and ERK pathways. PAI-2 is downregulated in PAH patients. PAI-2 attenuates PAH development by suppressing hPASMCs proliferation via the inhibition of PI3K/Akt and ERK pathways. PAI-2 may serve as a potential biomarker and therapeutic target for PAH.

Zhang S ，Wang J ，Qi X ，Tao X ，Xie W ，Wan J ，Shen YH ，Zhai Z ... -  《-》

The novel roles of YULINK in the migration, proliferation and glycolysis of pulmonary arterial smooth muscle cells: implications for pulmonary arterial hypertension.

Wu YC ，Wang WT ，Yang MC ，Su YT ，Yeh JL ，Hsu JH ，Wu JR ... -  《-》

Ligustrazine Suppresses Platelet-Derived Growth Factor-BB-Induced Pulmonary Artery Smooth Muscle Cell Proliferation and Inflammation by Regulating the PI3K/AKT Signaling Pathway.

Huang H ，Kong L ，Luan S ，Qi C ，Wu F ... -  《-》