MicroRNA-365 inhibits the proliferation of vascular smooth muscle cells by targeting cyclin D1

Thyrotropin induces atherosclerosis by upregulating large conductance Ca2+-activated K+ channel subunits

Hypothyroidism is associated with elevated levels of serum thyrotropin (TSH), which have been shown to promote abnormal proliferation of vascular smooth muscle cells and contribute to the development of atherosclerosis. However, the specific mechanisms underlying the TSH-induced abnormal proliferation of vascular smooth muscle cells remain unclear. The objective of this study was to investigate the role of TSH in the progression of atherosclerosis. Our research findings revealed that hypothyroidism can trigger early atherosclerotic changes in the aorta of Wistar rats. In alignment with our in vitro experiments, we observed that TSH induces abnormal proliferation of aortic smooth muscle cells by modulating the expression of α and β1 subunits of large conductance Ca2+-activated K+ (BKCa) channels within these cells via the cAMP/PKA signaling pathway. These results collectively indicate that TSH acts through the cAMP/PKA signaling pathway to upregulate the expression of α and β1 subunits of BKCa channels, thereby promoting abnormal proliferation of arterial smooth muscle cells. These findings may provide a basis for the clinical prevention and treatment of atherosclerosis caused by elevated TSH levels.

Inhibitory Effect of β-Sitosterol on the Ang II-Induced Proliferation of A7r5 Aortic Smooth Muscle Cells

Objective

To explore the effects of β-sitosterol on VSMC proliferation.

Materials and Methods

A7r5 cells were pretreated with 2 µM angiotensin II (Ang II) for 24 hr to establish an excessive VSMC proliferation model, followed by treatment with β-sitosterol for 24 hr. Cells were divided into five groups: control, Ang II, and Ang II + β-sitosterol (2, 4, 8 µM). CCK-8 assay, flow cytometry, and Ad-mCherry-GFP-LC3B assay analyzed cell proliferation, cell cycle, cell apoptosis, and autophagic flux. Additionally, the expression of proteins was detected by the western blotting.

Results

β-Sitosterol effectively inhibited Ang II-induced A7r5 cell proliferation (IC50 : 6.841 µM at 24 hr). It achieved this by arresting cell cycle progression, promoting apoptosis, inhibiting autophagy, and suppressing the contractile-synthetic phenotypic switch. Mechanistically, β-sitosterol downregulated PCNA, Cyclin D1, and Bcl-2, while upregulating pro-caspase 3, cleaved-caspase 3, and Bax to induce cell cycle arrest and apoptosis. Additionally, it suppressed the contractile-synthetic phenotypic transformation by downregulating OPN and upregulating α-SMA. The Ad-mCherry-GFP-LC3B Assay and western blotting revealed β-sitosterol's autophagy inhibitory effects by downregulating LC3, ULK1, and Beclin-1 while upregulating P62 expression. Discussion and Conclusion. This study found for the first time that β-sitosterol could inhibit the proliferation of A7r5 cells induced by Ang II. β-Sitosterol treatment may be recommended as a therapeutic strategy to prevent the cardiovascular diseases.

Association between miR-365 polymorphism and ischemic stroke in a Chinese population

Background

Ischemic stroke (IS) represents a major cause of morbidity and mortality across the globe. The aberrant expression of miR-365 has been found to be implicated in a wide array of human diseases, including atherosclerosis and cancer. Studies on single-nucleotide polymorphisms (SNPs) in miRNA genes can help gain insight into the susceptibility to the condition. This study aimed to examine the relationship between miR-365 SNPs and the risk of IS.

Methods

The study recruited 215 IS patients and 220 controls. The SNPscans genotyping was employed to genotype three polymorphic loci (rs121224, rs30230, and rs178553) of miR-365. The relative expression of miR-365 in peripheral blood mononuclear cells of the patients and controls was determined by using real-time quantitative PCR.

Results

The miR-365 rs30230 polymorphism exhibited a significant association with the risk of developing IS (TC vs. CC: adjusted OR = 0.55, 95% CI: 0.33-0.92, P = 0.022; TT vs. CC: adjusted OR = 0.34, 95% CI: 0.14-0.85, P = 0.021; TC +TT vs. CC: adjusted OR = 0.51, 95% CI: 0.31-0.83, P = 0.007; T vs. C: adjusted OR = 0.57, 95% CI: 0.39-0.83, P = 0.004). Haplotype analysis revealed that the C-T-G haplotype was associated with a decreased risk of IS (OR = 0.68, 95% CI: 0.46-1.00, P = 0.047). Furthermore, miR-365 expression was significantly higher in IS patients than in controls (P < 0.001). Interestingly, patients with rs30230 TC or TT genotypes had lower miR-365 levels compared to their counterparts with CC genotypes (P < 0.001).

Conclusions

The miR-365 rs30230 polymorphism might bear an association with IS susceptibility in the Chinese population, and the rs30230 TC/TT genotype might be a protective factor against IS.

Regulation of the Cell Cycle by ncRNAs Affects the Efficiency of CDK4/6 Inhibition

Cyclin-dependent kinases (CDKs) regulate cell division at multiple levels. Aberrant proliferation induced by abnormal cell cycle is a hallmark of cancer. Over the past few decades, several drugs that inhibit CDK activity have been created to stop the development of cancer cells. The third generation of selective CDK4/6 inhibition has proceeded into clinical trials for a range of cancers and is quickly becoming the backbone of contemporary cancer therapy. Non-coding RNAs, or ncRNAs, do not encode proteins. Many studies have demonstrated the involvement of ncRNAs in the regulation of the cell cycle and their abnormal expression in cancer. By interacting with important cell cycle regulators, preclinical studies have demonstrated that ncRNAs may decrease or increase the treatment outcome of CDK4/6 inhibition. As a result, cell cycle-associated ncRNAs may act as predictors of CDK4/6 inhibition efficacy and perhaps present novel candidates for tumor therapy and diagnosis.

Role of MicroRNAs and their corresponding ACE2/Apelin signaling pathways in hypertension

Hypertension is controlled via the alteration of microRNAs (miRNAs), their therapeutic targets angiotensin II type I receptor (AT1R) and cross talk of signaling pathways. The stimulation of the Ang II/AT1R pathway by deregulation of miRNAs, has also been linked to cardiac remodeling as well as the pathophysiology of high blood pressure. As miRNAs have been associated to ACE2/Apelin and Mitogen-activated protein kinases (MAPK) signaling, it has revealed an utmost protective impact over hypertension and cardiovascular system. The ACE2-coupled intermodulation between RAAS, Apelin system, MAPK signaling pathways, and miRNAs reveal the practicalities of high blood pressure. The research of miRNAs may ultimately lead to the expansion of an innovative treatment strategy for hypertension, which indicates the need to explore them further at the molecular level. Therefore, here we have focused on the mechanistic importance of miRNAs in hypertension, ACE2/Apelin signaling as well as their biological functions, with a focus on interplay and crosstalk between ACE2/Apelin signaling, miRNAs, and hypertension, and the progress in miRNA-based diagnostic techniques with the goal of facilitating the development of new hypertension-controlling therapeutics.

Effects of insulin on the proliferation and global gene expression profile of A7r5 cells

Insulin contributes to atherosclerosis, but the potential mechanisms are kept unclear. In this study, insulin promoted proliferation of A7r5 cells. Microarray analysis indicated that insulin significantly changed 812 probe sets of genes, including 405 upregulated and 407 downregulated ones (fold change ≥ 1.5 or ≤ - 1.5; p < 0.05). Gene ontology analysis showed that the differentially expressed genes were involved in a number of processes, including the regulation of cell proliferation/migration/cycle, apoptotic process, oxidative stress, inflammatory response, mitogen-activated protein kinase (MAPK) activity, lipid metabolic process and extracellular matrix organization. Moreover, Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated that the genes were involved in biosynthesis of amino acids, fatty acid metabolism, glycolysis/gluconeogenesis, metabolic pathways, regulation of autophagy, cell cycle and apoptosis, as well as the PI3K-Akt, MAPK, mTOR and NF-κB signaling pathways. Additionally, insulin enhanced phosphorylation of MAPK kinase 1/2 and Akt, suggesting activation of the MAPK and PI3K-Akt signaling pathways. Inhibition of ERK1/2 reduced insulin-induced proliferation. This study revealed the proliferative effects of insulin and displayed global gene expression profile of A7r5 cells stimulated by insulin, suggesting new insight into the molecular pathogenesis of insulin promoting atherosclerosis.

Identification of microRNAs and their target gene networks implicated in arterial wall remodelling in giant cell arteritis

OBJECTIVES

To identify dysregulated microRNAs (miRNAs) and their gene targets in temporal arteries from GCA patients, and determine their association with GCA pathogenesis and related arterial wall remodelling.

METHODS

We included 93 formalin-fixed, paraffin-embedded temporal artery biopsies (TABs) from treatment-naïve patients: 54 positive and 17 negative TABs from clinically proven GCA patients, and 22 negative TABs from non-GCA patients. miRNA expression analysis was performed with miRCURY LNA miRNome Human PCR Panels and quantitative real-time PCR. miRNA target gene prediction and pathway enrichment analysis was performed using the miRDB and Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) databases, respectively.

RESULTS

Dysregulation of 356 miRNAs was determined in TAB-positive GCA arteries, among which 78 were significantly under-expressed and 22 significantly overexpressed above 2-fold, when compared with non-GCA controls. Specifically, TAB-positive GCA arteries were characterized by a significant overexpression of 'pro-synthetic' (miR-21-3p/-21-5p/-146a-5p/-146b-5p/-424-5p) and under-expression of 'pro-contractile' (miR-23b-3p/-125a-5p/-143-3p/-143-5p/-145-3p/-145-5p/-195-5p/-365a-3p) vascular smooth muscle cell phenotype-associated regulatory miRNAs. These miRNAs targeted gene pathways involved in the arterial remodelling and regulation of the immune system, and their expression correlated with the extent of intimal hyperplasia in TABs from GCA patients. Notably, the expression of miR-21-3p/-21-5p/-146a-5p/-146b-5p/-365a-3p differentiated between TAB-negative GCA arteries and non-GCA temporal arteries, revealing these miRNAs as potential biomarkers of GCA.

CONCLUSION

Identification of dysregulated miRNAs involved in the regulation of the vascular smooth muscle cell phenotype and intimal hyperplasia in GCA arterial lesions, and detection of their expression profiles, enables a novel insight into the complexity of GCA pathogenesis and implies their potential utilization as diagnostic and prognostic biomarkers of GCA.

MicroRNA bta-miR-365-3p inhibits proliferation but promotes differentiation of primary bovine myoblasts by targeting the activin A receptor type I

Background

MicroRNAs act as post-transcriptional regulators that repress translation or degrade mRNA transcripts. Each microRNA has many mRNA targets and each mRNA may be targeted by several microRNAs. Skeletal muscles express a plethora of microRNA genes that regulate muscle development and function by controlling the expression of protein-coding target genes. To expand our understanding of the role of microRNA, specifically bta-miR-365-3p, in muscle biology, we investigated its functions in regulating primary bovine myoblast proliferation and differentiation.

Results

Firstly, we found that bta-miR-365-3p was predominantly expressed in skeletal muscle and heart tissue in Chinese Qinchuan beef cattle. Quantitative PCR and western blotting results showed that overexpression of bta-miR-365-3p significantly reduced the expression levels of cyclin D1 (CCND1), cyclin dependent kinase 2 (CDK2) and proliferating cell nuclear antigen (PCNA) but stimulated the expression levels of muscle differentiation markers, i.e., MYOD1, MYOG at both mRNA and protein level. Moreover, downregulation of bta-miR-365-3p increased the expression of CCND1, CDK2 and PCNA but decreased the expression of MYOD1 and MYOG at both mRNA and protein levels. Furthermore, flow cytometry, EdU proliferation assays and immunostaining results showed that increased levels of bta-miR-365-3p suppressed cell proliferation but promoted myotube formation, whereas decreased levels of bta-miR-365-3p resulted in the opposite consequences. Finally, we identified that activin A receptor type I (ACVR1) could be a direct target of bta-miR-365-3p. It was demonstrated that bta-miR-365-3p can bind to the 3’UTR of ACVR1 gene to regulate its expression based on dual luciferase gene reporter assays. Consistently, knock-down of ACVR1 was associated with decreased expressions of CDK2, CCND1 and PCNA but increased expression of MYOG and MYOD1 both at mRNA and protein level.

Conclusion

Collectively, these data suggested that bta-miR-365-3p represses proliferation but promotes differentiation of bovine myoblasts through several biological mechanisms involving downregulation of ACVR1.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40104-020-00528-0.

Identification of securinine as vascular protective agent targeting atherosclerosis in vascular endothelial cells, smooth muscle cells, and apolipoprotein E deficient mice

BACKGROUND

Atherosclerosis is a chronic vascular disease and characterized by accumulation within the intima of inflammatory cells, smooth muscle cells, lipid, and connective tissue.

PURPOSE

The purpose of the present study was to identify natural agents that commonly reverse advanced atherosclerotic plaque to early atherosclerotic plaque.

METHODS

Differentially expressed genes (DEGs) were analyzed in silico. The differentially expressed genes from 9 intimal thickening and 8 fibrous cap atheroma tissue which were collected from GEO data were assessed by the connectivity map. Natural candidate securinine, a main compound from Securinega suffruticosa, was selected and administrated 1, 5 mg/kg/day in apolipoprotein-E-deficient (ApoE KO) mice for 18 weeks.

RESULTS

Securinine significantly showed lowered blood pressure and improvement of metabolic parameters with hyperlipidemia. The impairment in vasorelaxation was remarkably decreased by treatment with securinine. H&E staining revealed that treatment with securinine reduced atherosclerotic lesions. Securinine suppressed the expression of adhesion molecules and matrix metalloproteinase-2/-9 in both ApoE KO and vascular endothelial cells (HUVEC). In HUVEC pretreatment with securinine significantly inhibited ROS generation and NF-κB activation. Growth curve assays using the real-time cell analyzer showed that securinine significantly decreased TNF-α-induced aortic smooth muscle cell proliferation and migration in a dose-dependent manner.

CONCLUSION

Securinine may be a potential natural candidate for the treatment of atherosclerosis because it attenuates vascular inflammation and dysfunction as well as vascular lesion.

Potential role of ACE2-related microRNAs in COVID-19-associated nephropathy

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for coronavirus disease (COVID-19), potentially have severe kidney adverse effects. This organ expressed angiotensin-converting enzyme 2 (ACE2), the transmembrane protein which facilitate the entering of the virus into the cell. Therefore, early detection of the kidney manifestations of COVID-19 is crucial. Previous studies showed ACE2 role in various indications of this disease, especially in kidney effects. The MicroRNAs (miRNAs) in this organ affected ACE2 expression. Therefore, this review aims at summarizing the literature of a novel miRNA-based therapy and its potential applications in COVID-19-associated nephropathy. Furthermore, previous studies were analyzed for the kidney manifestations of COVID-19 and the miRNAs role that were published on the online databases, namely MEDLINE (PubMed) and Scopus. Several miRNAs, particularly miR-18 (which was upregulated in nephropathy), played a crucial role in ACE2 expression. Therefore, the antimiR-18 roles were summarized in various primate models that aided in developing the therapy for ACE2 related diseases.

MicroRNA-532-5p protects against atherosclerosis through inhibiting vascular smooth muscle cell proliferation and migration

Background

The present study aimed to explore the expression and clinical value of miR-532-5p in atherosclerosis (AS) patients, and analyze its regulating effect on biological behaviors of vascular smooth muscle cells (VSMCs).

Methods

A total of 103 AS patients and 77 healthy controls were included. The expression level of miR-532-5p was measured using quantitative real-time PCR (qRT-PCR). A receiver operating characteristic (ROC) analysis was counted to assess the diagnostic value of miR-532-5p in AS. CCK-8 and Transwell assay were used to detect the role of miR-532-5p in VSMCs proliferation and migration.

Results

MiR-532-5p was downregulated in AS patients compared with that in healthy controls. Serum miR-532-5p was inversely related to the carotid intima-media thickness (CIMT) in AS patients. A ROC curve was conducted with an area under the curve (AUC) of 0.897, with high sensitivity and specificity. Overexpression of miR-532-5p inhibited cell proliferation and migration in VSMCs, whereas miR-532-5p downregulation had a reverse effect.

Conclusions

Decreased expression of miR-532-5p might be a potential diagnostic biomarker for AS. Overexpression of miR-532-5p inhibits the proliferation and migration of VSMCs. The present results indicate a therapeutic potential of miR-532-5p for AS.

Early Programming of Adult Systemic Essential Hypertension

Cardiovascular diseases are being included in the study of developmental origins of health and disease (DOHaD) and essential systemic hypertension has also been added to this field. Epigenetic modifications are one of the main mechanisms leading to early programming of disease. Different environmental factors occurring during critical windows in the early stages of life may leave epigenetic cues, which may be involved in the programming of hypertension when individuals reach adulthood. Such environmental factors include pre-term birth, low weight at birth, altered programming of different organs such as the blood vessels and the kidney, and living in disadvantageous conditions in the programming of hypertension. Mechanisms behind these factors that impact on the programming include undernutrition, oxidative stress, inflammation, emotional stress, and changes in the microbiota. These factors and their underlying causes acting at the vascular level will be discussed in this paper. We also explore the establishment of epigenetic cues that may lead to hypertension at the vascular level such as DNA methylation, histone modifications (methylation and acetylation), and the role of microRNAs in the endothelial cells and blood vessel smooth muscle which participate in hypertension. Since epigenetic changes are reversible, the knowledge of this type of markers could be useful in the field of prevention, diagnosis or epigenetic drugs as a therapeutic approach to hypertension.

The role of microRNAs in the involvement of vascular smooth muscle cells in the development of atherosclerosis

MicroRNAs (miRNAs) are a class of nonprotein-encoding RNAs of ~22 nucleotides in length that bind to or complement each other with a target gene messenger RNA (mRNA) to promote mRNA degradation or inhibit translation of the target mRNA. The protein required [such as Toll-like receptor (TLR) proteins] is controlled at an optimal level. By affecting protein translation, miRNAs have become powerful regulators of biological processes, including development, differentiation, cell proliferation, and apoptosis. MiRNAs are involved in the regulation of proliferation, migration, and apoptosis of vascular smooth muscle cells (VSMCs), thereby affecting the formation of atherosclerosis (AS). In recent years, the role and mechanism of miRNAs involved in AS development in VSMCs have been studied extensively. In the current study, the results and progress in miRNA research are reviewed.

Overexpression of TGF-β enhances the migration and invasive ability of ectopic endometrial cells via ERK/MAPK signaling pathway

Endometriosis is a common gynecological disease with manifestations of endometrial-like tissue outside the uterus. Transforming growth factor-β (TGF-β) is known to facilitate a series of biological events in many cells, including migration. However, the roles of TGF-β in endometriosis still remain largely unknown. The aim of the present study was to discover the role of TGF-β1 in endometriosis development and progression and its associated mechanisms. It was demonstrated that the expression of TGF-β1 was significantly elevated in endometriosis in comparison with that in normal tissue. Overexpression of TGF-β increased the proliferation and upregulated proliferating cell nuclear antigen and cyclin D1 in endometrial stromal cells (ESCs). Furthermore, TGF-β overexpression also triggered a series of biological events occurring in ESCs, including cell migration and invasion, and activated the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) signaling pathway. The inhibition of the ERK/MAPK pathway reversed the previous effects of TGF-β overexpression. Collectively, the present results indicate that overexpression of TGF-β enhances the migration and invasion of ectopic ESCs via the ERK/MAPK signaling pathway, providing theoretical evidence for the development of new treatment methods targeting the TGF-β-ERK/MAPK signaling pathway for prophylaxis of endometriosis.

MicroRNA-365 promotes the contractile phenotype of venous smooth muscle cells and inhibits neointimal formation in rat vein grafts

The high rate of autologous vein graft failure caused by neointimal hyperplasia remains an unresolved issue in the field of cardiovascular surgery; therefore, it is important to explore new methods for protecting against neointimal hyperplasia. MicroRNA-365 has been reported to inhibit the proliferation of vascular smooth muscle cells (SMCs). This study aimed to test whether adenovirus-mediated miR-365 was able to attenuate neointimal formation in rat vein grafts. We found that miR-365 expression was substantially reduced in vein grafts following engraftment. In vitro, overexpression of miR-365 promoted smooth muscle-specific gene expression and inhibited venous SMC proliferation and migration. Consistent with this, overexpression of miR-365 in a rat vein graft model significantly reduced grafting-induced neointimal formation and effectively improved the hemodynamics of the vein grafts. Mechanistically, we identified that cyclin D1 as a potential downstream target of miR-365 in vein grafts. Specially, to increase the efficiency of miR-365 gene transfection, a 30% poloxamer F-127 gel containing 0.25% trypsin was mixed with adenovirus and spread around the vein grafts to increase the adenovirus contact time and penetration. We showed that adenovirus-mediated miR-365 attenuated venous SMC proliferation and migration in vitro and effectively inhibited neointimal formation in rat vein grafts. Restoring expression of miR-365 is a potential therapeutic approach for the treatment of vein graft failure. © 2019 IUBMB Life, 2019.

The microRNAs Regulating Vascular Smooth Muscle Cell Proliferation: A Minireview

Vascular smooth muscle cell (VSMC) proliferation plays a critical role in atherosclerosis. At the beginning of the pathologic process of atherosclerosis, irregular VSMC proliferation promotes plaque formation, but in advanced plaques VSMCs are beneficial, promoting the stability and preventing rupture of the fibrous cap. Recent studies have demonstrated that microRNAs (miRNAs) expressed in the vascular system are involved in the control of VSMC proliferation. This review summarizes recent findings on the miRNAs in the regulation of VSMC proliferation, including miRNAs that exhibit the inhibition or promotion of VSMC proliferation, and their targets mediating the regulation of VSMC proliferation. Up to now, most of the studies were performed only in cultured VSMC. While the modulation of miRNAs is emerging as a promising strategy for the regulation of VSMC proliferation, most of the effects of miRNAs and their targets in vivo require further investigation.

PDGFBB promotes proliferation and migration via regulating miR-1181/STAT3 axis in human pulmonary arterial smooth muscle cells

Platelet-derived growth factor (PDGF) can induce hyperproliferation of pulmonary artery smooth muscle cells (PASMCs), which is a key causative factor to the occurrence and progression of pulmonary arterial hypertension (PAH). We previously identified that miR-1181 is significantly downregulated by PDGFBB in human PASMCs. In this work, we further explore the function of miR-1181 and underlying regulatory mechanisms in PDGF-induced PASMCs. First, the expression pattern of miR-1181 was characterized under PDGFBB treatment, and PDGF receptor/PKCβ signaling was found to repress miR-1181 expression. Then, gain- and loss-of-function experiments were respectively conducted and revealed the prominent role of miR-1181 in inhibiting PASMC proliferation and migration. Flow cytometry analysis suggested that miR-1181 regulated the PASMC proliferation through influencing the cell cycle transition from G0/G1 to S phase. Moreover, we exhibited that miR-1181 targeting STAT3 formed a regulatory axis to modulate PASMC proliferation. Finally, serum miR-1181 expression was also observed to be reduced in adult and newborn patients with PAH. Overall, this study provides novel findings that the miR-1181/STAT3 axis mediated PDGFBB-induced dysfunction in human PASMCs, implying a potential use of miR-1181 as a therapeutic and diagnostic candidate for the vascular remodeling diseases.

Exercise Training-Induced Changes in MicroRNAs: Beneficial Regulatory Effects in Hypertension, Type 2 Diabetes, and Obesity

MicroRNAs are small non-coding RNAs that regulate gene expression post-transcriptionally. They are involved in the regulation of physiological processes, such as adaptation to physical exercise, and also in disease settings, such as systemic arterial hypertension (SAH), type 2 diabetes mellitus (T2D), and obesity. In SAH, microRNAs play a significant role in the regulation of key signaling pathways that lead to the hyperactivation of the renin-angiotensin-aldosterone system, endothelial dysfunction, inflammation, proliferation, and phenotypic change in smooth muscle cells, and the hyperactivation of the sympathetic nervous system. MicroRNAs are also involved in the regulation of insulin signaling and blood glucose levels in T2D, and participate in lipid metabolism, adipogenesis, and adipocyte differentiation in obesity, with specific microRNA signatures involved in the pathogenesis of each disease. Many studies report the benefits promoted by exercise training in cardiovascular diseases by reducing blood pressure, glucose levels, and improving insulin signaling and lipid metabolism. The molecular mechanisms involved, however, remain poorly understood, especially regarding the participation of microRNAs in these processes. This review aimed to highlight microRNAs already known to be associated with SAH, T2D, and obesity, as well as their possible regulation by exercise training.

MicroRNA-365 targets multiple oncogenes to inhibit proliferation, invasion, and self-renewal of aggressive endometrial cancer cells

Background

MicroRNA-365 (miR-365) has been reported to be a tumor suppressor miRNA. However, the role of miR-365 in progression of endometrial cancer (EC) has not been explored, in this study, we have found that re-expression of miRNA-365 inhibits cell proliferation, causes apoptosis and senescence.

Materials and methods

Overexpression of miR-365 attenuated cell migration and invasion, inhibited sphere-forming capacity, and enhanced the chemosensitivity to paclitaxel. In silico prediction tools identified the potential targets of miR-365.

Results

We identified EZH2 and FOS as targets of miR-365 and found that downregulating these genes imitated the tumor suppressive effect of miR-365. The outcomes of the study suggested that a reverse correlation existed between low miR-365 and overexpression of FOS and EZH2 in EC tissue specimens.

Conclusion

The study concludes that miR-365 acts as an important tumor suppressor and contributes by suppressing cell invasiveness, proliferation, and self-renewal in cancer cell lines by regulating multiple oncogenes. We establish that miR-365-EZH2/FOS pathway is an important target for treating EC.

Luteolin Inhibits Vascular Smooth Muscle Cell Proliferation and Migration by Inhibiting TGFBR1 Signaling

Vascular smooth muscle cell (VSMC) proliferation and migration play a critical role in the development of arterial remodeling during various vascular diseases including atherosclerosis, hypertension, and related diseases. Luteolin is a food-derived flavonoid that exerts protective effects on cardiovascular diseases. Here, we investigated whether transforming growth factor-β receptor 1 (TGFBR1) signaling underlies the inhibitory effects of luteolin on VSMC proliferation and migration. We found that luteolin reduced the proliferation and migration of VSMCs, specifically A7r5 and HASMC cells, in a dose-dependent manner, based on MTS and EdU, and Transwell and wound healing assays, respectively. We also demonstrated that it inhibited the expression of proliferation-related proteins including PCNA and Cyclin D1, as well as the migration-related proteins MMP2 and MMP9, in a dose-dependent manner by western blotting. In addition, luteolin dose-dependently inhibited the phosphorylation of TGFBR1, Smad2, and Smad3. Notably, adenovirus-mediated overexpression of TGFBR1 enhanced TGFBR1, Smad2, and Smad3 activation in VSMCs and partially blocked the inhibitory effect of luteolin on TGFBR1, Smad2, and Smad3. Moreover, overexpression of TGFBR1 rescued the inhibitory effects of luteolin on the proliferation and migration of VSMCs. Additionally, molecular docking showed that this compound could dock onto an agonist binding site of TGFBR1, and that the binding energy between luteolin and TGFBR1 was -10.194 kcal/mol. Simulations of molecular dynamics showed that TGFBR1-luteolin binding was stable. Collectively, these data demonstrated that luteolin might inhibit VSMC proliferation and migration by suppressing TGFBR1 signaling.

MiR-147b influences vascular smooth muscle cell proliferation and migration via targeting YY1 and modulating Wnt/β-catenin activities

Cardiovascular disease is the leading cause of death worldwide. Dysregulation of microRNAs (miRNAs) has been found to be associated with cardiovascular diseases such as atherosclerosis. In the present study, we examined the role of miR-147b in the proliferation and migration of vascular smooth muscle cells (VSMCs). Quantitative real-time PCR was performed to determine the expression levels of miR-147b and Yin Yang 1 (YY1) mRNA. CCK-8, transwell migration and wound healing assays were used to determine cell proliferation and migration of VSMCs, respectively. Luciferase reporter assay confirmed the downstream target of miR-147b. The protein level of YY1 was measured by western blot analysis. Platelet-derived growth factor-bb (PDGF-bb) treatment promoted cell proliferation and increased miR-147b expression in VSMCs. Overexpression of miR-147b enhanced cell proliferation and migration of VSMCs, while knock-down of miR-147b suppressed cell proliferation and migration of VSMCs or PDGF-bb-treated VSMCs. Further, bioinformatics prediction and luciferase reporter assay showed that YY1 was a downstream target of miR-147b, and miR-147b negatively regulated the mRNA and protein expression of YY1 in VSMCs. Overexpression of YY1 inhibited cell proliferation and migration of VSMCs and attenuated the effects of miR-147b overexpression on cell proliferation and migration. In addition, overexpression of miR-147b increased the Wnt/β-catenin signaling activities in VSMCs. In conclusion, our results suggest that miR-147b plays important roles in the control of cell proliferation and migration of VSMCs possibly via targeting YY1.

Deciphering Non-coding RNAs in Cardiovascular Health and Disease

After being long considered as “junk” in the human genome, non-coding RNAs (ncRNAs) currently represent one of the newest frontiers in cardiovascular disease (CVD) since they have emerged in recent years as potential therapeutic targets. Different types of ncRNAs exist, including small ncRNAs that have fewer than 200 nucleotides, which are mostly known as microRNAs (miRNAs), and long ncRNAs that have more than 200 nucleotides. Recent discoveries on the role of ncRNAs in epigenetic and transcriptional regulation, atherosclerosis, myocardial ischemia/reperfusion (I/R) injury and infarction (MI), adverse cardiac remodeling and hypertrophy, insulin resistance, and diabetic cardiomyopathy prompted vast interest in exploring candidate ncRNAs for utilization as potential therapeutic targets and/or diagnostic/prognostic biomarkers in CVDs. This review will discuss our current knowledge concerning the roles of different types of ncRNAs in cardiovascular health and disease and provide some insight on the cardioprotective signaling pathways elicited by the non-coding genome. We will highlight important basic and clinical breakthroughs that support employing ncRNAs for treatment or early diagnosis of a variety of CVDs, and also depict the most relevant limitations that challenge this novel therapeutic approach.

Cardiovascular Risk Factors and Markers

Cardiovascular risk is assessed for the prediction and appropriate management of patients using collections of identified risk markers obtained from clinical questionnaire information, concentrations of certain blood molecules (e.g., N-terminal proB-type natriuretic peptide fragment and soluble receptors of tumor-necrosis factor-α and interleukin-2), imaging data using various modalities, and electrocardiographic variables, in addition to traditional risk factors.

LncRNA BANCR facilitates vascular smooth muscle cell proliferation and migration through JNK pathway

Deregulated migration and proliferation of vascular smooth muscle cells (VSMCs) acts a crucial role in the pathogenesis of many cardiovascular diseases such as atherosclerosis, coronary heart disease and hypertension. Long noncoding RNAs (lncRNAs) play crucial functional roles in a lot of biological processes such as cell development, cell proliferation, differentiation and invasion. In our study, we demonstrated that the BANCR expression level was upregulated in the atherosclerotic plaques tissues compared to in the normal vessels tissues. TNF-α could emhance the VSMCs proliferation. The expression level of BANCR and p-JNK were upregulated and activated in the proliferating VSMCs. Overexpression of BANCR enhanced VSMCs proliferation and migration. Elevated expression of BANCR induced JNK activation, which can be decreased by the specific JNK inhibitor SP600125. We demonstrated that ectopic expression of BANCR increased the VSMCs proliferation and migration through activating JNK pathway. These data suggested that lncRNA BANCR acts a crucial role in the regulating VSMCs proliferation and migration partly by activating the JNK pathway.

MicroRNA-217 suppresses homocysteine-induced proliferation and migration of vascular smooth muscle cells via N-methyl-D-aspartic acid receptor inhibition

Hyperhomocysteine has become a critical risk for atherosclerosis and can stimulate proliferation and migration of vascular smooth muscle cells (VSMCs). N-methyl-D-aspartic acid receptor (NMDAR) is a receptor of homocysteine and mediates the effects of homocysteine on VSMCs. Bioinformatics analysis has shown NMDAR is a potential target of microRNA-217 (miR-217), which exerts multiple functions in cancer tumorigenesis and carotid plaque progression. In this study, we sought to investigate the role of miR-217 in VSMCs phenotype transition under homocysteine exposure and elucidate its effect on atherosclerotic plaque formation. After treating with several doses of homocysteine (0-8 × 10(-4)  mol/L) for 24 hours, the expression of miR-217 in HA-VSMCs and rat aortic VSMCs was not altered. Intriguingly, the expression of NMDAR mRNA and protein was reduced by homocysteine in a dose-dependent manner. Transfection of miR-217 mimic significantly inhibited the proliferation and migration of VSMCs with homocysteine treatment, while transfection of miR-217 inhibitor promoted VSMCs migration. Moreover, miR-217 mimic down-regulated while miR-217 inhibitor up-regulated NMDAR protein expression but not NMDAR mRNA expression. Through luciferase reporter assay, we showed that miR-217 could directly bind to the 3'-UTR of NMDAR. MiR-217 mimic transfection also released the inhibition of cAMP-response element-binding protein (CREB)-PGC-1α signalling induced by homocysteine. Additionally, restoration of PGC-1α expression via AdPGC-1α infection markedly suppressed VSMCs proliferation through the degradation of NADPH oxidase (NOX1) and reduction of reactive oxygen species (ROS). Collectively, our study identified the role of miR-217 in regulating VSMCs proliferation and migration, which might serve as a target for atherosclerosis therapy.

MicroRNA‑146a promotes the proliferation of rat vascular smooth muscle cells by downregulating p53 signaling

The present study aimed to detect and verify gene expression profile differences for microRNA (miR)‑146a and its role in the proliferation of vascular smooth muscle cells (VSMCs). Artificially synthesized miR‑146a mimics, miR‑146 inhibitor, scramble‑miRNA or PBS was transfected into cultured primary rat VSMCs in vitro. Reverse transcription‑quantitative polymerase chain reaction confirmed that the miR‑146a expression level was significantly decreased in VSMCs treated with miR‑146a inhibitor (P<0.01). Cell Counting Kit‑8 was used to determine the proliferation ability, which demonstrated that proliferation was significantly decreased in VSMCs treated with miR‑146a inhibitor (P<0.01). Microarray expression profiling analysis revealed that the p53 signal pathway was upregulated in VSMCs treated with the miR‑146a inhibitor. Compared with untransfected VSMCs, the mRNA and protein expression levels of caspase‑3 and phosphatase and tensin homolog (PTEN) in p53 signal transduction pathway did not exhibit a significant difference (P>0.05); however, the mRNA and protein expression levels of p53 were significantly decreased in cells transfected with miR‑146a mimics and increased in miR‑146a inhibitor transfected cells (both P<0.01). The mRNA and protein expression levels of cyclin D1 significantly increased in miR‑146a mimics transfected cells and decreased in cells transfected with the miR‑146a inhibitor (both P<0.05). The present data indicated that miR‑146a may promote the proliferation of rat VSMCs by downregulating p53 and upregulating cyclin D1 expression.

MicroRNA-137 and microRNA-195* inhibit vasculogenesis in brain arteriovenous malformations

OBJECTIVE

Brain arteriovenous malformations (AVMs) are the most common cause of nontraumatic intracerebral hemorrhage in young adults. The genesis of brain AVM remains enigmatic. We investigated microRNA (miRNA) expression and its contribution to the pathogenesis of brain AVMs.

METHODS

We used a large-scale miRNA analysis of 16 samples including AVMs, hemangioblastoma, and controls to identify a distinct AVM miRNA signature. AVM smooth muscle cells (AVMSMCs) were isolated and identified by flow cytometry and immunohistochemistry, and candidate miRNAs were then tested in these cells. Migration, tube formation, and CCK-8-induced proliferation assays were used to test the effect of the miRNAs on phenotypic properties of AVMSMCs. A quantitative proteomics approach was used to identify protein expression changes in AVMSMCs treated with miRNA mimics.

RESULTS

A distinct AVM miRNA signature comprising a large portion of lowly expressed miRNAs was identified. Among these miRNAs, miR-137 and miR-195* levels were significantly decreased in AVMs and constituent AVMSMCs. Experimentally elevating the level of these microRNAs inhibited AVMSMC migration, tube formation, and survival in vitro and the formation of vascular rings in vivo. Proteomics showed the protein expression signature of AVMSMCs and identified downstream proteins regulated by miR-137 and miR-195* that were key signaling proteins involved in vessel development.

INTERPRETATION

Our results indicate that miR-137 and miR-195* act as vasculogenic suppressors in AVMs by altering phenotypic properties of AVMSMCs, and that the absence of miR-137 and miR-195* expression leads to abnormal vasculogenesis. Ann Neurol 2017;82:371-384.

miR-4632 mediates PDGF-BB-induced proliferation and antiapoptosis of human pulmonary artery smooth muscle cells via targeting cJUN

MicroRNAs (miRNAs) can regulate the proliferative status of pulmonary artery smooth muscle cells (PASMCs), which is a core factor modulating pulmonary vascular remodeling diseases, such as atherosclerosis and pulmonary arterial hypertension (PAH). Our previous work has shown that miR-4632, a rarely reported miRNA, is significantly downregulated in platelet-derived growth factor (PDGF)-BB-stimulated human pulmonary artery smooth muscle cells (HPASMCs), yet its cell function and the underlying molecular mechanisms remain to be elucidated. Here, we find that miR-4632 is highly expressed in HPASMCs and its expression significantly decreased in response to different stimuli. Functional studies revealed that miR-4632 inhibited proliferation and promoted apoptosis of HPASMCs but had no effects on cell contraction and migration. Furthermore, the cJUN was identified as a direct target gene of miR-4632, while knockdown of cJUN was necessary for miR-4632-mediated HPASMC proliferation and apoptosis. In addition, the downregulation of miR-4632 by PDGF-BB was found to associate with histone deacetylation through the activation of PDGF receptor/phosphatidylinositol 3'-kinase/histone deacetylase 4 signaling. Finally, the expression of miR-4632 was reduced in the serum of patients with PAH. Overall, our results suggest that miR-4632 plays an important role in regulating HPASMC proliferation and apoptosis by suppression of cJUN, providing a novel therapeutic miRNA candidate for the treatment of pulmonary vascular remodeling diseases. It also implies that serum miR-4632 has the potential to serve as a circulating biomarker for PAH diagnosis.

Silencing miR-16 Expression Promotes Angiotensin II Stimulated Vascular Smooth Muscle Cell Growth

miRNAs are a class of non-coding endogenous small RNAs that control gene expression at the posttranscriptional level and involved in cell proliferation, migration and differentiation. Dysregulation of miRNA expression is involved in a variety of human diseases including cardiovascular diseases. miRNAs have been shown to regulate vascular smooth muscle cell (VSMC) function and play vital roles in hypertension, restenosis and atherosclerosis. Here we reported that miR-16 as one of miRNAs in the miR-15 family was highly expressed in vascular smooth muscle cells (VSMCs) and involved in angiotensin II (Ang II) mediated VSMC signaling pathways. Ang II downregulated miR-16 expression in VSMCs. Lentiviral vector mediated miR-16 knockdown promoted Ang II-induced cell proliferation and migration. Moreover, silencing miR-16 enhanced Ang II induced cell cycle associated gene expression and promoted Ang II-activated cell proliferative pathways ERK1/2 and p38. Our finding demonstrated for the first time that miR-16 was a potential therapeutic target by participating in the Ang II-associated multiple signaling pathways in cardiovascular diseases.

MicroRNA-365 accelerates cardiac hypertrophy by inhibiting autophagy via the modulation of Skp2 expression

Evidence is emerging of a tight link between cardiomyocyte autophagy and cardiac hypertrophy (CH). Sustained exposure to stress leads CH to progress to heart failure. Several miRNAs have been described in heart failure, and miRNA-based therapeutic approaches are being pursued. Although microRNA-365 (miR-365) has been testified as a positive modulator of CH, the specific mechanism remains unclear. In the present study, we observed that miR-365 expression was up-regulated in hypertrophic cardiomyocytes both in vivo and in vitro, and was accompanied by dysregulation of autophagy. We found that miR-365 negatively modulates autophagy in hypertrophic cardiomyocytes by targeting Skp2. Overexpression of Skp2 promoted autophagy and rescued CH induced by Ang-II; conversely, Skp2 knockdown further inhibited autophagy and CH. Furthermore, we found that the activation of mammalian target of rapamycin (mTOR) signaling was regulated by Skp2 following Ang-II treatment, as indicated by the up-regulation of p-S6K and p-4EBP1 levels. The inactivation of mTOR by rapamycin completely abolished the Ang-II-induced inhibition of autophagy. In conclusion, our study provides substantial evidence that miR-365 and its target gene Skp2 play a functional role in CH and suggests the development of novel therapeutic options based on miR-365 and Skp2.

A spleen tyrosine kinase inhibitor attenuates the proliferation and migration of vascular smooth muscle cells

Background

Pathologic vascular smooth muscle cell (VSMC) proliferation and migration after vascular injury promotes the development of occlusive vascular disease. Therefore, an effective chemical agent to suppress aberrant proliferation and migration of VSMCs can be a potential therapeutic modality for occlusive vascular disease such as atherosclerosis and restenosis. To find an anti-proliferative chemical agent for VSMCs, we screened an in-house small molecule library, and the selected small molecule was further validated for its anti-proliferative effect on VSMCs using multiple approaches, such as cell proliferation assays, wound healing assays, transwell migration assays, and ex vivo aortic ring assay.

Results

Among 43 initially screened small molecule inhibitors of kinases that have no known anti-proliferative effect on VSMCs, a spleen tyrosine kinase (Syk) inhibitor (BAY61-3606) showed significant anti-proliferative effect on VSMCs. Further experiments indicated that BAY61 attenuated the VSMC proliferation in both concentration- and time-dependent manner, and it also significantly suppressed the migration of VSMCs as assessed by both wound healing assays and transwell assays. Additionally, BAY61 suppressed the sprouting of VSMCs from endothelium-removed aortic rings.

Conclusion

The present study identified a Syk kinase inhibitor as a potent VSMC proliferation and migration inhibitor and warrants further studies to elucidate its underlying molecular mechanisms, such as its primary target, and to validate its in vivo efficacy as a therapeutic agent for restenosis and atherosclerosis.

miR-365 targets β-arrestin 2 to reverse morphine tolerance in rats

Morphine tolerance is a challenging clinical problem that limits its clinical application in pain treatment. Non-coding microRNAs (miRNAs) modulate gene expression in a post transcriptional manner, and their dysregulation causes various diseases. However, the significance of miRNAs in morphine tolerance is still poorly understood. In the present study, we hypothesized that microRNA-365 (miR-365) is a key functional small RNA that reverses morphine tolerance through regulation of β-arrestin 2 in rats. Here, microarray analysis and quantitative real-time PCR showed that miR-365 was robustly decreased in the spinal cord after chronic morphine administration. In situ hybridization and immunochemistry double staining showed that miR-365 was expressed in neurons of the spinal cord. We identified β-arrestin 2 as the target gene of miR-365 by bioinformatics analysis and luciferase reporter assay. The data showed that overexpression of miR-365 prevented and reversed established morphine tolerance, and increased expression of miR-365 caused a decrease in expression of β-arrestin 2 protein. miR-365 downregulation is involved in the development and maintenance of morphine tolerance through regulation of β-arrestin 2, and miR-365 upregulation provides a promising and novel approach for treatment of morphine tolerance.

MiR-328 targeting PIM-1 inhibits proliferation and migration of pulmonary arterial smooth muscle cells in PDGFBB signaling pathway

MicroRNAs (miRNAs) have been recognized to mediate PDGF-induced cell dysregulation, but their exact functions remain to be elucidated. By using a sensitive S-Poly(T) Plus qRT-PCR method, the expression profiling of 1,078 miRNAs were investigated in pulmonary artery smooth muscle cells (PASMCs) with or without PDGFBB stimulation. MiR-328 was found as a prominent down-regulated miRNA, displaying a specific dose- and time-dependent downregulation upon PDGFBB exposure. Functional analyses revealed that miR-328 could inhibit PASMCs proliferation and migration both with and without PDGFBB treatment. The Ser/Thr-protein kinase-1 (PIM-1) was identified as a direct target of miR-328, and functionally confirmed by a rescue experiment. In addition, the decrease of miR-328 by PDGFBB might be due to the increased expression of DNA methylation transferase 1 (DNMT1) and DNA methylation. Finally, serum miR-328 level was downregulated in PAH patients associated with congenital heart disease (CHD- PAH). Overall, this study provides critical insight into fundamental regulatory mechanism of miR-328 in PDGFBB-activited PASMCs via targeting PIM- 1, and implies the potential of serum miR-328 level as a circulating biomarker for CHD- PAH diagnosis.

Hydroxymethylation of microRNA-365-3p Regulates Nociceptive Behaviors via Kcnh2

DNA 5-hydroxylmethylcytosine (5hmC) catalyzed by ten-eleven translocation methylcytosine dioxygenase (TET) occurs abundantly in neurons of mammals. However, the in vivo causal link between TET dysregulation and nociceptive modulation has not been established. Here, we found that spinal TET1 and TET3 were significantly increased in the model of formalin-induced acute inflammatory pain, which was accompanied with the augment of genome-wide 5hmC content in spinal cord. Knockdown of spinal TET1 or TET3 alleviated the formalin-induced nociceptive behavior and overexpression of spinal TET1 or TET3 in naive mice produced pain-like behavior as evidenced by decreased thermal pain threshold. Furthermore, we found that TET1 or TET3 regulated the nociceptive behavior by targeting microRNA-365-3p (miR-365-3p). Formalin increased 5hmC in the miR-365-3p promoter, which was inhibited by knockdown of TET1 or TET3 and mimicked by overexpression of TET1 or TET3 in naive mice. Nociceptive behavior induced by formalin or overexpression of spinal TET1 or TET3 could be prevented by downregulation of miR-365-3p, and mimicked by overexpression of spinal miR-365-3p. Finally, we demonstrated that a potassium channel, voltage-gated eag-related subfamily H member 2 (Kcnh2), validated as a target of miR-365-3p, played a critical role in nociceptive modulation by spinal TET or miR-365-3p. Together, we concluded that TET-mediated hydroxymethylation of miR-365-3p regulates nociceptive behavior via Kcnh2.

SIGNIFICANCE STATEMENT

Mounting evidence indicates that epigenetic modifications in the nociceptive pathway contribute to pain processes and analgesia response. Here, we found that the increase of 5hmC content mediated by TET1 or TET3 in miR-365-3p promoter in the spinal cord is involved in nociceptive modulation through targeting a potassium channel, Kcnh2. Our study reveals a new epigenetic mechanism underlying nociceptive information processing, which may be a novel target for development of antinociceptive drugs.

Redox signaling, Nox5 and vascular remodeling in hypertension

Purpose of review

Extensive data indicate a role for reactive oxygen species (ROS) and redox signaling in vascular damage in hypertension. However, molecular mechanisms underlying these processes remain unclear, but oxidative post-translational modification of vascular proteins is critical. This review discusses how proteins are oxidatively modified and how redox signaling influences vascular smooth muscle cell growth and vascular remodeling in hypertension. We also highlight Nox5 as a novel vascular ROS-generating oxidase.

Recent findings

Oxidative stress in hypertension leads to oxidative imbalance that affects vascular cell function through redox signaling. Many Nox isoforms produce ROS in the vascular wall, and recent findings show that Nox5 may be important in humans. ROS regulate signaling by numerous processes including cysteine oxidative post-translational modification such as S-nitrosylation, S-glutathionylation and sulfydration. In vascular smooth muscle cells, this influences cellular responses to oxidative stimuli promoting changes from a contractile to a proliferative phenotype.

Summary

In hypertension, Nox-induced ROS production is increased, leading to perturbed redox signaling through oxidative modifications of vascular proteins. This influences mitogenic signaling and cell cycle regulation, leading to altered cell growth and vascular remodeling in hypertension.

Noncoding RNAs in smooth muscle cell homeostasis: implications in phenotypic switch and vascular disorders

Vascular smooth muscle cells (SMC) are a highly specialized cell type that exhibit extraordinary plasticity in adult animals in response to a number of environmental cues. Upon vascular injury, SMC undergo phenotypic switch from a contractile-differentiated to a proliferative/migratory-dedifferentiated phenotype. This process plays a major role in vascular lesion formation and during the development of vascular remodeling. Vascular remodeling comprises the accumulation of dedifferentiated SMC in the intima of arteries and is central to a number of vascular diseases such as arteriosclerosis, chronic obstructive pulmonary disease or pulmonary hypertension. Therefore, it is critical to understand the molecular mechanisms that govern SMC phenotype. In the last decade, a number of new classes of noncoding RNAs have been described. These molecules have emerged as key factors controlling tissue homeostasis during physiological and pathological conditions. In this review, we will discuss the role of noncoding RNAs, including microRNAs and long noncoding RNAs, in the regulation of SMC plasticity.

Gingerol Inhibits Serum-Induced Vascular Smooth Muscle Cell Proliferation and Injury-Induced Neointimal Hyperplasia by Suppressing p38 MAPK Activation

Purpose:

Gingerol inhibits growth of cancerous cells; however, its role in vascular smooth muscle cell (VSMC) proliferation is not known. The present study investigated the effect of gingerol on VSMC proliferation in cell culture and during neointima formation after balloon injury.

Method and Results:

Rat VSMCs or carotid arteries were harvested at 15 minutes, 30 minutes, 1, 6, 12, and 24 hours of fetal bovine serum (FBS; 10%) stimulation or balloon injury, respectively. Gingerol prevented FBS (10%)-induced proliferation of VSMCs in a dose-dependent manner (50 μmol/L-400 μmol/L). The FBS-induced proliferating cell nuclear antigen (PCNA) upregulation and p27Kip1 downregulation were also attenuated in gingerol (200 μmol/L) pretreated cells. Fetal bovine serum-induced p38 mitogen-activated protein kinase (MAPK) activation, PCNA upregulation, and p27Kip1 downregulation were abrogated in gingerol (200 μmol/L) and p38 MAPK inhibitor (SB203580, 10 μmol/L) pretreated cells. Balloon injury induced time-dependent p38 MAPK activation in the carotid artery. Pretreatment with gingerol (200 μmol/L) significantly attenuated injury-induced p38 MAPK activation, PCNA upregulation, and p27Kip1 downregulation. After 14 days of balloon injury, intimal thickening, neointimal proliferation, and endothelial dysfunction were significantly prevented in gingerol pretreated arteries. In isolated organ bath studies, gingerol (30 nmol/L-300 μmol/L) inhibited phenylephrine-induced contractions and induced dose-dependent relaxation of rat thoracic aortic rings in a partially endothelium-dependent manner.

Conclusion:

Gingerol prevented FBS-induced VSMC proliferation and balloon injury-induced neointima formation by regulating p38 MAPK. Vasodilator effect of gingerol observed in the thoracic aorta was partially endothelium dependent. Gingerol is thus proposed as an attractive agent for modulating VSMC proliferation, vascular reactivity, and progression of vascular proliferative diseases.

The short and long of noncoding sequences in the control of vascular cell phenotypes

The two principal cell types of importance for normal vessel wall physiology are smooth muscle cells and endothelial cells. Much progress has been made over the past 20 years in the discovery and function of transcription factors that coordinate proper differentiation of these cells and the maintenance of vascular homeostasis. More recently, the converging fields of bioinformatics, genomics, and next generation sequencing have accelerated discoveries in a number of classes of noncoding sequences, including transcription factor binding sites (TFBS), microRNA genes, and long noncoding RNA genes, each of which mediates vascular cell differentiation through a variety of mechanisms. Alterations in the nucleotide sequence of key TFBS or deviations in transcription of noncoding RNA genes likely have adverse effects on normal vascular cell phenotype and function. Here, the subject of noncoding sequences that influence smooth muscle cell or endothelial cell phenotype will be summarized as will future directions to further advance our understanding of the increasingly complex molecular circuitry governing normal vascular cell differentiation and how such information might be harnessed to combat vascular diseases.

Mechanisms and therapeutic potential of microRNAs in hypertension

Hypertension is the major risk factor for the development of stroke, coronary artery disease, heart failure and renal disease. The underlying cellular and molecular mechanisms of hypertension are complex and remain largely elusive. MicroRNAs (miRNAs) are short, noncoding RNA fragments of 22-26 nucleotides and regulate protein expression post-transcriptionally by targeting the 3'-untranslated region of mRNA. A growing body of recent research indicates that miRNAs are important in the pathogenesis of arterial hypertension. Herein, we summarize the current knowledge regarding the mechanisms of miRNAs in cardiovascular remodeling, focusing specifically on hypertension. We also review recent progress of the miRNA-based therapeutics including pharmacological and nonpharmacological therapies (such as exercise training) and their potential applications in the management of hypertension.

The ACE2/Apelin Signaling, MicroRNAs, and Hypertension

The renin-angiotensin aldosterone system (RAAS) plays a pivotal role in the development of hypertension. Angiotensin converting enzyme 2 (ACE2), which primarily metabolises angiotensin (Ang) II to generate the beneficial heptapeptide Ang-(1-7), serves as a negative regulator of the RAAS. Apelin is a second catalytic substrate for ACE2 and functions as an inotropic and cardiovascular protective peptide. The physiological effects of Apelin are exerted through binding to its receptor APJ, a seven-transmembrane G protein-coupled receptor that shares significant homology with the Ang II type 1 receptor (AT1R). The deregulation of microRNAs, a class of short and small noncoding RNAs, has been shown to involve cardiovascular remodeling and pathogenesis of hypertension via the activation of the Ang II/AT1R pathway. MicroRNAs are linked with modulation of the ACE2/Apelin signaling, which exhibits beneficial effects in the cardiovascular system and hypertension. The ACE2-coupled crosstalk among the RAAS, the Apelin system, and microRNAs provides an important mechanistic insight into hypertension. This paper focuses on what is known about the ACE2/Apelin signaling and its biological roles, paying particular attention to interactions and crosstalk among the ACE2/Apelin signaling, microRNAs, and hypertension, aiming to facilitate the exploitation of new therapeutic medicine to control hypertension.

microRNAs Distinctively Regulate Vascular Smooth Muscle and Endothelial Cells: Functional Implications in Angiogenesis, Atherosclerosis, and In-Stent Restenosis

Endothelial cells (EC) and vascular smooth muscle cells (VSMC) are the main cell types within the vasculature. We describe here how microRNAs (miRs)--noncoding RNAs that can regulate gene expression via translational repression and/or post-transcriptional degradation--distinctively modulate EC and VSMC function in physiology and disease. In particular, the specific roles of miR-126 and miR-143/145, master regulators of EC and VSMC function, respectively, are deeply explored. We also describe the mechanistic role of miRs in the regulation of the pathophysiology of key cardiovascular processes including angiogenesis, atherosclerosis, and in-stent restenosis post-angioplasty. Drawbacks of currently available therapeutic options are discussed, pointing at the challenges and potential clinical opportunities provided by miR-based treatments.

Stigmasterol protects against Ang II-induced proliferation of the A7r5 aortic smooth muscle cell-line

Excessive proliferation of vascular smooth muscle cells is a crucial event in the pathogenesis of several cardiovascular diseases, including atherosclerosis and restenosis.

MicroRNAs in atherosclerosis

Micro-ribonucleic acids (miRNAs) are a class of endogenous non-coding ribonucleic acids that regulate gene expression. MiRNAs have been shown to act as key regulators in the vascular system, with wide-ranging physio-pathological effects. Atherosclerotic disease is a leading cause of morbidity and mortality worldwide. This review presents current knowledge on miRNAs implicated in atherosclerosis susceptibility, development and progression. They are involved in cell phenotype switching, response to shear stress, cell senescence, adhesion molecule expression, macrophage response to oxidised low-density lipoprotein, Toll-like receptor 4 expression, neointimal lesion formation, plaque angiogenesis and cellular cholesterol homeostasis. Clinically, early work has demonstrated the utility of miRNAs for differentiating patients with arterial disease from controls and predicting future cardiac events; this highlights potential diagnostic and prognostic roles. MiRNA involvement in the crucial stages of atherosclerosis promises new hope in treating arterial disease. However, issues regarding multiple miRNA targets, stability and delivery continue to present challenges.