Salusin-β contributes to vascular remodeling associated with hypertension via promoting vascular smooth muscle cell proliferation and vascular fibrosis

Functional and Proteomic Investigations Reveal Major Royal Jelly Protein 1 Associated with Anti-hypertension Activity in Mouse Vascular Smooth Muscle Cells

Vascular smooth muscle cells (VSMCs) are a major cell type of the arterial wall and their functionality is associated with blood pressure regulation. Although royal jelly (RJ) has reported effects on anti-hypertension, the mechanism of blood pressure regulation by major royal jelly protein 1 (MRJP1), the most abundant RJ protein, is still unknown. The mrjp1 gene was inserted into mouse VSMCs to investigate how MRJP1 influences VSMC functionality by functional and proteomic analysis. The expression of MRJP1 in VSMCs significantly reduced cell contraction, migration, and proliferation, suggesting a potential role in decreasing hypertension via action on VSMCs. These anti-hypertension activities were further observed in the changes of the proteome setting of mouse VSMCs. Among 675 different proteins after MRJP1 expression, 646 were down-regulated and significantly enriched in pathways implicated in VSMC contraction and migration, which suggest MRJP1 lowers VSMC contraction and migration by inhibiting muscle filament movement. The down-regulated proteins also enriched pathways in proliferation, indicating that MRJP1 hinders VSMC proliferation by reducing the supply of energy and genetic material. This is the first report integrating MRJP1 into VSMC, revealing the function and mechanism correlated with anti-hypertensive activity. This offers a therapeutic potential to control hypertension by gene-therapy using bee-products.

miR-145 mediated the role of aspirin in resisting VSMCs proliferation and anti-inflammation through CD40

Background

Aspirin (ASA) is the most widely used medicine to prevent cardiovascular diseases; however, the mechanisms by which ASA exerts its anti-proliferative effect remain not fully understood. This study was designed to investigate whether miR-145 is involved in the regulation of vascular smooth muscle cells’ (VSMCs) proliferation and to determine the anti-inflammatory effects of ASA via its regulation of CD40 to provide a new theoretical basis for the pharmacological effect of aspirin.

Methods

The TNF-α induced proliferation model of VSMCs was divided into different groups with or without aspirin. Cell proliferation was detected by EdU; Real-time PCR was used to detect the mRNA expression of miR-145, CD40, and Calponin, a VSMCs differentiation marker gene. Western blot was used to detect the protein expression of CD40; ELISA was used to determine the concentrations of the inflammatory cytokine IL-6 in cell supernatants.

Results

The proliferation of VSMCs was stimulated by TNF-α and accompanied by decreased levels of Calponin. TNF-α also decreased the levels of miR-145 and increased the levels of CD40 and IL-6. Pretreatment with 20 μg/mL of aspirin in VSMCs could partially block the above-mentioned effects induced by TNF-α. The protective effects of ASA in VSMCs were reversed by a pretreatment with a miR-145 inhibitor. We also found that the expression of miR-145 in peripheral blood mononuclear cells in ischemic stroke patients was significantly increased after a 10-day treatment with aspirin.

Conclusion

miR-145 is involved in the anti-proliferation and anti-inflammation effects of aspirin on VSMCs by inhibiting the expression of CD40.

Salusin-β Promotes Vascular Smooth Muscle Cell Migration and Intimal Hyperplasia After Vascular Injury via ROS/NFκB/MMP-9 Pathway

AIMS

Media-to-intima migration of vascular smooth muscle cells (VSMCs) is critical to intimal thickening in atherosclerosis and restenosis after coronary angioplasty. The aim of this study is to determine the effects of salusin-β on VSMC migration and intimal hyperplasia after vascular injury and the underlying mechanism.

RESULTS

In vitro, salusin-β promoted VSMC migration, which was attenuated by matrix metalloproteinase (MMP)-9 inhibition. Inhibition or knockdown of p65-nuclear factor kappa beta (NFκB) in VSMCs suppressed salusin-β-induced MMP-9 expression and VSMC migration. Salusin-β increased NADPH oxidase 2 (NOX2) expression and reactive oxygen species (ROS) production, which were prevented by NOX2-small interfering RNA (siRNA) transfection. Salusin-β-induced p65-NFκB translocation, MMP-9 expression, and VSMC migration were inhibited by ROS scavenger, NADPH oxidase inhibitor, or NOX2-siRNA. In vivo, carotid artery ligation-induced vascular injury resulted in intimal hyperplasia in injured artery in rats. Salusin-β was upregulated in the injured carotid arteries of rats, which was attributed to reduced miR-133a-3p expression. Knockdown of salusin-β with siRNA attenuated the vascular injury-induced intimal thickening, p65-NFκB nuclear translocation, and NOX2 and MMP-9 expressions in rats.

INNOVATION

Salusin-β is a critical modulator in VSMC migration and neointima formation in response to vascular injury.

CONCLUSIONS

Salusin-β promotes VSMC migration and vascular injury-induced intimal hyperplasia via MMP-9 accumulation due to NOX2 activation, followed by ROS production, IκBα phosphorylation and degradation, and p65-NFκB translocation. We propose that salusin-β may be important in the VSMC migration and neointima of some vascular diseases. Antioxid. Redox Signal. 24, 1045-1057.

Salusin-β contributes to vascular inflammation associated with pulmonary arterial hypertension in rats

OBJECTIVE

Inflammation is closely linked to pulmonary arterial hypertension (PAH). Salusin-β, a bioactive peptide, has been reported to participate in vascular inflammation. We therefore hypothesized that salusin-β contributes to monocrotaline (MCT)-induced PAH in rats.

METHODS

Male Sprague-Dawley rats were treated with MCT (60 mg kg(-1), single intraperitoneal injection). Salusin-β expression in the lungs of the MCT-treated rats was evaluated using immunofluorescence staining, western blot, and real-time PCR. For salusin-β blockade assay, rats injected with MCT were given a chronic infusion of anti-salusin-β immunoglobulin G (IgG) (salusin-β blocker, 1.0 μg kg(-1) h(-1)) or isotype-matched control IgG. Four weeks after MCT+anti-salusin-β treatment, the effects of salusin-β blockade were determined using hemodynamics, western blot, real-time PCR, and immunohistochemical detection. The effect of salusin-β on human pulmonary arterial endothelial cell (HPAEC) function was detected by adhesion and tube formation experiments in vitro.

RESULTS

Salusin-β expression was significantly increased in the lungs of the MCT-treated rats, and immunofluorescence results showed that salusin-β was predominantly expressed in pulmonary macrophages and vascular endothelial cells. Salusin-β blockade significantly ameliorated PAH by acting against pulmonary vascular remodeling, decreasing macrophage infiltration, and reducing pro-inflammatory cytokine expression and nuclear factor-kappa B (NF-κB) activity in the lungs of the MCT-treated rats. In addition, salusin-β could induce cell adhesion and accelerate angiogenesis by activating the NF-κB pathway and promoting pro-inflammatory cytokine expression in the cultured HPAECs. This effect was suppressed by addition of the NF-κB inhibitor, N-acetyl-L-cysteine.

CONCLUSIONS

Salusin-β plays a crucial role in the development of MCT-induced PAH models.

Long non-coding RNA ATB promotes growth and epithelial-mesenchymal transition and predicts poor prognosis in human prostate carcinoma

Long non-coding RNAs (lncRNAs) have been identified to be critical mediators in various tumors associated with cancer progression. Long non-coding RNA activated by TGF-β (lncRNA-ATB) is a stimulator of epithelial-mesenchymal transition (EMT) and serves as a novel prognostic biomarker for hepatocellular carcinoma. However, the biological role and clinical significance of lncRNA-ATB in human prostate cancer have yet to be fully elucidated. The present study was designed to explore the expression of lncRNA-ATB in human prostate cancer patients and the role of lncRNA-ATB in prostate cancer cells. We showed that lncRNA-ATB expression was significantly upregulated in tumor tissues in patients with prostate cancer in comparison with adjacent non-tumor tissues. Further analysis indicted that high lncRNA-ATB expression may be an independent prognostic factor for biochemical recurrence (BCR)-free survival in prostate cancer patients. Overexpression of lncRNA-ATB promoted, and knockdown of lncRNA-ATB inhibited the growth of prostate cancer cells via regulations of cell cycle regulatory protein expression levels. In addition, lncRNA-ATB stimulated epithelial-mesenchymal transition (EMT) associated with ZEB1 and ZNF217 expression levels via ERK and PI3K/AKT signaling pathways. These results indicated that lncRNA-ATB may be considered as a new predictor in the clinical prognosis of patients with prostate cancer. Overexpression of lncRNA-ATB exerts mitogenic and EMT effects of prostate cancer via activation of ERK and PI3K/AKT signaling pathways.

Salusin-β induces foam cell formation and monocyte adhesion in human vascular smooth muscle cells via miR155/NOX2/NFκB pathway

Vascular smooth muscle cells (VSMCs) are indispensible components in foam cell formation. Salusin-β is a stimulator in the progression of atherosclerosis. Here, we showed that salusin-β increased foam cell formation evidenced by accumulation of lipid droplets and intracellular cholesterol content, and promoted monocyte adhesion in human VSMCs. Salusin-β increased the expressions and activity of acyl coenzyme A:cholesterol acyltransferase-1 (ACAT-1) and vascular cell adhesion molecule-1 (VCAM-1) in VSMCs. Silencing of ACAT-1 abolished the salusin-β-induced lipid accumulation, and silencing of VCAM-1 prevented the salusin-β-induced monocyte adhesion in VSMCs. Salusin-β caused p65-NFκB nuclear translocation and increased p65 occupancy at the ACAT-1 and VCAM-1 promoter. Inhibition of NFκB with Bay 11-7082 prevented the salusin-β-induced ACAT-1 and VCAM-1 upregulation, foam cell formation and monocyte adhesion in VSMCs. Scavenging ROS, inhibiting NADPH oxidase or knockdown of NOX2 abolished the effects of salusin-β on ACAT-1 and VCAM-1 expressions, p65-NFκB nuclear translocation, lipid accumulation and monocyte adhesion in VSMCs. Salusin-β increased miR155 expression, and knockdown of miR155 prevented the effects of salusin-β on ACAT-1 and VCAM-1 expressions, p65-NFκB nuclear translocation, lipid accumulation, monocyte adhesion and ROS production in VSMCs. These results indicate that salusin-β induces foam formation and monocyte adhesion via miR155/NOX2/NFκB-mediated ACAT-1 and VCAM-1 expressions in VSMCs.

Endogenous sulfur dioxide alleviates collagen remodeling via inhibiting TGF-β/Smad pathway in vascular smooth muscle cells

The study was designed to investigate the role of endogenous sulfur dioxide (SO₂) in collagen remodeling and its mechanisms in vascular smooth muscle cells (VSMCs). Overexpression of endogenous SO₂ synthase aspartate aminotransferase (AAT) 1 or 2 increased SO₂ levels and inhibited collagen I and III expressions induced by transforming growth factor (TGF)-β1 in VSMCs. In contrast, AAT1 or AAT2 knockdown induced a severe collagen deposition in TGF-β1-treated VSMCs. Furthermore, AAT1 or AAT2 overexpression suppressed procollagen I and III mRNA, upregulated matrix metalloproteinase (MMP)-13 expression, downregulated tissue inhibitors of MMP-1 level, and vice versa. Mechanistically, AAT1 or AAT2 overexpression inhibited phosphorylation of type I TGF-β receptor (TβRI) and Smad2/3 in TGF-β1-stimulated VSMCs. Whereas SB431542, an inhibitor of TGF-β1/Smad signaling pathway, attenuated excessive collagen deposition induced by AAT knockdown. Most importantly, ectopically expressing AAT or exogenous addition of 100 μM SO₂ blocked AAT deficiency-aggravated collagen accumulation in TGF-β1-stimulatd VSMCs, while no inhibition was observed at 100 μM ethyl pyruvate. These findings indicated that endogenous SO₂ alleviated collagen remodeling by controlling TGF-β1/TβRI/Smad2/3-mediated modulation of collagen synthesis and degradation.