The PGC-1α/NRF1/miR-378a axis protects vascular smooth muscle cells from FFA-induced proliferation, migration and inflammation in atherosclerosis

Local vascular Klotho mediates diabetes-induced atherosclerosis via ERK1/2 and PI3-kinase-dependent signaling pathways

BACKGROUND AND AIMS

Diabetes is one of the major causes of cardiovascular disease (CVD). As high as 29 % of patients with diabetes develop atherosclerosis. Vascular Smooth Muscle Cells (VSMCs) are a key mediator in the pathogenesis of atherosclerosis, generating pro-inflammatory and proliferative characteristics in atherosclerotic lesions.

METHODS

We used human atherosclerotic samples, developed diabetes-induced atherosclerotic mice, and generated loss of function and gain of function in Klotho human aortic smooth muscle cells to investigate the function of Klotho in atherosclerosis.

RESULTS

We found that Klotho expression is decreased in smooth muscle actin-positive cells in patients with diabetes and atherosclerosis. Consistent with human data, we found that Apoe knockout mice with streptozotocin-induced diabetes fed on a high-fat diet showed decreased expression of Klotho in SMCs. Additionally, these mice showed increased expression of TGF-β, MMP9, phosphorylation of ERK and Akt. Further, we utilized primary Human Aortic Smooth Muscle Cells (HASMCs) with d-glucose under dose-response and in time-dependent conditions to study the role of Klotho in these cells. Klotho gain of function and loss of function studies showed that Klotho inversely regulated the expression of atherosclerotic markers TGF-β, MMP2, MMP9, and Fractalkine. Further, High Glucose (HG) induced Akt, and ERK1/2 phosphorylation were enhanced or mitigated by endogenous Klotho deficiency or its overexpression respectively. PI3K/Akt and MAPK/ERK inhibition partially abolished the HG-induced upregulation of TGF-β, MMP2, MMP9, and Fractalkine. Additionally, Klotho knockdown increased the proliferation of HASMCs and enhanced α-SMA and TGF-β expression.

CONCLUSIONS

Taken together, these results indicate that local vascular Klotho is involved in diabetes-induced atherosclerosis, which is via PI3K/Akt and ERK1/2-dependent signaling pathways.

Peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) family in physiological and pathophysiological process and diseases

Peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) family (PGC-1s), consisting of three members encompassing PGC-1α, PGC-1β, and PGC-1-related coactivator (PRC), was discovered more than a quarter-century ago. PGC-1s are essential coordinators of many vital cellular events, including mitochondrial functions, oxidative stress, endoplasmic reticulum homeostasis, and inflammation. Accumulating evidence has shown that PGC-1s are implicated in many diseases, such as cancers, cardiac diseases and cardiovascular diseases, neurological disorders, kidney diseases, motor system diseases, and metabolic disorders. Examining the upstream modulators and co-activated partners of PGC-1s and identifying critical biological events modulated by downstream effectors of PGC-1s contribute to the presentation of the elaborate network of PGC-1s. Furthermore, discussing the correlation between PGC-1s and diseases as well as summarizing the therapy targeting PGC-1s helps make individualized and precise intervention methods. In this review, we summarize basic knowledge regarding the PGC-1s family as well as the molecular regulatory network, discuss the physio-pathological roles of PGC-1s in human diseases, review the application of PGC-1s, including the diagnostic and prognostic value of PGC-1s and several therapies in pre-clinical studies, and suggest several directions for future investigations. This review presents the immense potential of targeting PGC-1s in the treatment of diseases and hopefully facilitates the promotion of PGC-1s as new therapeutic targets.

NRF1 knockdown alleviates lipopolysaccharide-induced pulmonary inflammatory injury by upregulating DKK3 and inhibiting the GSK-3β/β-catenin pathway

Excessive inflammatory injury is the main cause of the incidence of severe neonatal pneumonia (NP) and associated deaths. Although dickkopf-3 (DKK3) exhibits anti-inflammatory activity in numerous pathological processes, its role in NP is still unknown. In this study, human embryonic lung WI-38 and MRC-5 cells were treated with lipopolysaccharide (LPS) to induce inflammatory injury of NP in vitro. The expression of DKK3 was downregulated in LPS-stimulated WI-38 and MRC-5 cells. DKK3 overexpression decreased LPS-induced inhibition of cell viability, and reduced LPS-induced apoptosis of WI-38 and MRC-5 cells. DKK3 overexpression also reduced LPS-induced production of pro-inflammatory factors such as ROS, IL-6, MCP-1, and TNF-α. Nuclear respiratory factors 1 (NRF1) knockdown was found to upregulate DKK3 and inactivate the GSK-3β/β-catenin pathway in LPS-injured WI-38 and MRC-5 cells. NRF1 knockdown also suppressed LPS-induced inhibition on cell viability, repressed LPS-induced apoptosis, and inhibited the accumulation of ROS, IL-6, MCP-1, and TNF-α in LPS-injured WI-38 and MRC-5 cells. DKK3 knockdown or re-activation of the GSK-3β/β-catenin pathway reversed the inhibitory effects of NRF1 knockdown on LPS-induced inflammatory injury. In conclusion, NRF1 knockdown can alleviate LPS-triggered inflammatory injury by regulating DKK3 and the GSK-3β/β-catenin pathway.

Myeloid BAF60a deficiency alters metabolic homeostasis and exacerbates atherosclerosis

Atherosclerosis, a leading health concern, stems from the dynamic involvement of immune cells in vascular plaques. Despite its significance, the interplay between chromatin remodeling and transcriptional regulation in plaque macrophages is understudied. We discovered the reduced expression of Baf60a, a component of the switch/sucrose non-fermentable (SWI/SNF) chromatin remodeling complex, in macrophages from advanced plaques. Myeloid-specific Baf60a deletion compromised mitochondrial integrity and heightened adhesion, apoptosis, and plaque development. BAF60a preserves mitochondrial energy homeostasis under pro-atherogenic stimuli by retaining nuclear respiratory factor 1 (NRF1) accessibility at critical genes. Overexpression of BAF60a rescued mitochondrial dysfunction in an NRF1-dependent manner. This study illuminates the BAF60a-NRF1 axis as a mitochondrial function modulator in atherosclerosis, proposing the rejuvenation of perturbed chromatin remodeling machinery as a potential therapeutic target.

MicroRNAs Regulate Function in Atherosclerosis and Clinical Implications

Background

Atherosclerosis is considered the most common cause of morbidity and mortality worldwide. Athermanous plaque formation is pathognomonic of atherosclerosis. The main feature of atherosclerosis is the formation of plaque, which is inseparable from endothelial cells, vascular smooth muscle cells, and macrophages. MicroRNAs, a small highly conserved noncoding ribonucleic acid (RNA) molecule, have multiple biological functions, such as regulating gene transcription, silencing target gene expression, and affecting protein translation. MicroRNAs also have various pharmacological activities, such as regulating cell proliferation, apoptosis, and metabolic processes. It is noteworthy that many studies in recent years have also proved that microRNAs play a role in atherosclerosis.

Methods

To summarize the functions of microRNAs in atherosclerosis, we reviewed all relevant articles published in the PubMed database before June 2022, with keywords "atherosclerosis," "microRNA," "endothelial cells," "vascular smooth muscle cells," "macrophages," and "cholesterol homeostasis," briefly summarized a series of research progress on the function of microRNAs in endothelial cells, vascular smooth muscle cells, and macrophages and atherosclerosis. Results and Conclusion. In general, the expression levels of some microRNAs changed significantly in different stages of atherosclerosis pathogenesis; therefore, MicroRNAs may become new diagnostic biomarkers for atherosclerosis. In addition, microRNAs are also involved in the regulation of core processes such as endothelial dysfunction, plaque formation and stabilization, and cholesterol metabolism, which also suggests the great potential of microRNAs as a therapeutic target.

MicroRNA regulation of phenotypic transformations in vascular smooth muscle: relevance to vascular remodeling

Alterations in the vascular smooth muscle cells (VSMC) phenotype play a critical role in the pathogenesis of several cardiovascular diseases, including hypertension, atherosclerosis, and restenosis after angioplasty. MicroRNAs (miRNAs) are a class of endogenous noncoding RNAs (approximately 19-25 nucleotides in length) that function as regulators in various physiological and pathophysiological events. Recent studies have suggested that aberrant miRNAs' expression might underlie VSMC phenotypic transformation, appearing to regulate the phenotypic transformations of VSMCs by targeting specific genes that either participate in the maintenance of the contractile phenotype or contribute to the transformation to alternate phenotypes, and affecting atherosclerosis, hypertension, and coronary artery disease by altering VSMC proliferation, migration, differentiation, inflammation, calcification, oxidative stress, and apoptosis, suggesting an important regulatory role in vascular remodeling for maintaining vascular homeostasis. This review outlines recent progress in the discovery of miRNAs and elucidation of their mechanisms of action and functions in VSMC phenotypic regulation. Importantly, as the literature supports roles for miRNAs in modulating vascular remodeling and for maintaining vascular homeostasis, this area of research will likely provide new insights into clinical diagnosis and prognosis and ultimately facilitate the identification of novel therapeutic targets.

Exosomes from human urine-derived stem cells carry NRF1 to alleviate bladder fibrosis via regulating miR-301b-3p/TGFβR1 pathway

Bladder outlet obstruction (BOO) is a common disease that always make the bladder develops from inflammation to fibrosis. This study was to investigate the effect of exosomes from human urine-derived stem cells (hUSCs) on bladder fibrosis after BOO and the underlying mechanism. The BOO mouse model was established by inserting a transurethral catheter, ligation of periurethral wire, and removal of the catheter. Mouse primary bladder smooth muscle cells (BSMCs) were isolated and treated with TGFβ1 to mimic the bladder fibrosis model in vitro. Exosomes from hUSCs (hUSC-Exos) were injected into the bladder of BOO mice and added into the culture of TGFβ1-induced BSMCs. The associated factors in mouse bladder tissues and BSMCs were detected. It was confirmed that the treatment of hUSC-Exos alleviated mouse bladder fibrosis and down-regulated fibrotic markers (a-SMA and collagen III) in bladder tissues and TGFβ1-induced BSMCs. Overexpression of NRF1 in hUSC-Exos further improved the effects of hUSC-Exos on bladder fibrosis both in vivo and in vitro. TGFβR1 was a target of NRF1 and miR-301b-3p, and miR-301b-3p was a target of NRF1. It was next characterized that hUSC-Exos carried NRF1 to up-regulate miR-301B-3p, thereby reducing TGFβR1level. Our results illustrated that hUSC-Exos carried NRF1 to alleviate bladder fibrosis through regulating miR-301b-3p/TGFβR1 pathway.

Phenotypic plasticity of vascular smooth muscle cells in vascular calcification: Role of mitochondria

Vascular calcification (VC) is an important hallmark of cardiovascular disease, the osteo-/chondrocyte phenotype differentiation of vascular smooth muscle cells (VSMCs) is the main cause of vascular calcification. Accumulating evidence shows that mitochondrial dysfunction may ultimately be more detrimental in the VSMCs calcification. Mitochondrial participate in essential cellular functions, including energy production, metabolism, redox homeostasis regulation, intracellular calcium homeostasis, apoptosis, and signal transduction. Mitochondrial dysfunction under pathological conditions results in mitochondrial reactive oxygen species (ROS) generation and metabolic disorders, which further lead to abnormal phenotypic differentiation of VSMCs. In this review, we summarize existing studies targeting mitochondria as a treatment for VC, and focus on VSMCs, highlighting recent progress in determining the roles of mitochondrial processes in regulating the phenotype transition of VSMCs, including mitochondrial biogenesis, mitochondrial dynamics, mitophagy, mitochondrial energy metabolism, and mitochondria/ER interactions. Along these lines, the impact of mitochondrial homeostasis on VC is discussed.

Whole-transcriptome sequencing and ceRNA interaction network of temporomandibular joint osteoarthritis

Purpose: The aim of this study was to conduct a comprehensive transcriptomic analysis to explore the potential biological functions of noncoding RNA (ncRNAs) in temporomandibular joint osteoarthritis (TMJOA). Methods: Whole transcriptome sequencing was performed to identify differentially expressed genes (DEGs) profiles between the TMJOA and normal groups. The functions and pathways of the DEGs were analyzed using Metascape, and a competitive endogenous RNA (ceRNA) network was constructed using Cytoscape software. Results: A total of 137 DEmRNAs, 65 DEmiRNAs, 132 DElncRNAs, and 29 DEcircRNAs were identified between the TMJOA and normal groups. Functional annotation of the DEmRNAs revealed that immune response and apoptosis are closely related to TMJOA and also suggested key signaling pathways related to TMJOA, including chronic depression and PPAR signaling pathways. We identified vital mRNAs, including Klrk1, Adipoq, Cryab, and Hspa1b. Notably, Adipoq expression in cartilage was significantly upregulated in TMJOA compared with normal groups (10-fold, p < 0.001). According to the functional analysis of DEmRNAs regulated by the ceRNA network, we found that ncRNAs are involved in the regulation of autophagy and apoptosis. In addition, significantly DEncRNAs (lncRNA-COX7A1, lncRNA-CHTOP, lncRNA-UFM1, ciRNA166 and circRNA1531) were verified, and among these, circRNA1531 (14.5-fold, p < 0.001) and lncRNA-CHTOP (14.8-fold, p < 0.001) were the most significantly downregulated ncRNAs. Conclusion: This study showed the potential of lncRNAs, circRNAs, miRNAs, and mRNAs may as clinical biomarkers and provides transcriptomic insights into their functional roles in TMJOA. This study identified the transcriptomic signatures of mRNAs associated with immunity and apoptosis and the signatures of ncRNAs associated with autophagy and apoptosis and provides insight into ncRNAs in TMJOA.

Effects of NRF-1 and PGC-1α cooperation on HIF-1α and rat cardiomyocyte apoptosis under hypoxia

BACKGROUND

Hypoxia is a primary inducer of cardiomyocyte injury, its significant marker being hypoxia-induced cardiomyocyte apoptosis. Nuclear respiratory factor-1 (NRF-1) and hypoxia-inducible factor-1α (HIF-1α) are transcriptional regulatory elements implicated in multiple biological functions, including oxidative stress response. However, their roles in hypoxia-induced cardiomyocyte apoptosis remain unknown. The effect HIF-1α, together with NRF-1, exerts on cardiomyocyte apoptosis also remains unclear.

METHODS

We established a myocardial hypoxia model and investigated the effects of these proteins on the proliferation and apoptosis of rat cardiomyocytes (H9C2) under hypoxia. Further, we examined the association between NRF-1 and HIF-1α to improve the current understanding of NRF-1 anti-apoptotic mechanisms.

RESULTS

The results show that NRF-1 and HIF-1α are important anti-apoptotic molecules in H9C2 cells under hypoxia, although their regulatory mechanisms differ. NRF-1 could bind to the promoter region of Hif1a and negatively regulate its expression. Additionally, HIF-1β exhibited competitive binding with NRF-1 and HIF-1α, demonstrating a synergism between NRF-1 and the peroxisome proliferator-activated receptor-gamma coactivator-1α.

CONCLUSION

These results indicate that cardiomyocytes can regulate different molecular patterns to tolerate hypoxia, providing a novel methodological framework for studying cardiomyocyte apoptosis under hypoxia.

Activating PGC-1α-mediated signaling cascades in the aorta contributes to the amelioration of vascular senescence and atherosclerosis by 2,3,4',5-tetrahydroxystilbene-2-O-β-d-glycoside

BACKGROUND

2,3,4',5-tetrahydroxystilbene-2-O-β-d-glycoside (TSG), the main active polyphenolic component of Polygonum multiflorum, possesses many pharmacological activities. Its anti-aging effect influences a variety of tissues with diverse mechanisms. However, the effectiveness and exact mechanisms of TSG against vascular senescence in atherosclerosis remain unclear. The present study is aimed to investigate the effects of TSG against vascular senescence in atherosclerosis both in vivo and in vitro, and the possible underlying mechanisms focusing on aortic peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α)-mediated signaling cascades which have never been studied.

METHODS

In vivo, 12-mo-old male LDLr-/- mice were randomly separated into control, high-fat diet (HFD), and TSG -treatment groups. At the end of the 12 weeks, the blood samples and aorta tissues of mice were collected for further analysis. In vitro, to mimic the condition of endothelial senescence in hyperlipidemic mice, human aortic endothelial cells (HAECs) were incubated with oxidized low-density lipoprotein (ox-LDL) to induce senescence.

RESULTS

TSG administration improved lipid profiles, ameliorated HFD-exacerbated vascular senescence and atherosclerosis. The protective effect of TSG via inhibiting telomere malfunction, oxidative stress, and mitochondrial damage was found both in vivo and in vitro. Notably, TSG administration increased aortic PGC-1α mRNA and protein expression along with the regulation of its targeted genes TERT, NRF1, TFAM, Mn-SOD, and catalase. Further, by using PGC-1α siRNA in ox-LDL-treated HAECs, it is proved that TSG reduced endothelial senescence, telomere malfunction, oxidative stress, and mitochondrial damage at least partly through activating the PGC-1α pathway.

CONCLUSIONS

These results provide new evidence for TSG in the treatment of atherosclerosis and the activation of aortic PGC-1α is involved in its beneficial effects.

Molecular basis of the association between transcription regulators nuclear respiratory factor 1 and inhibitor of DNA binding protein 3 and the development of microvascular lesions

The prognosis of patients with microvascular lesions remains poor because vascular remodeling eventually obliterates the lumen. Here we have focused our efforts on vessel dysfunction in two different organs, the lung and brain. Despite tremendous progress in understanding the importance of blood vessel integrity, gaps remain in our knowledge of the underlying molecular factors contributing to vessel injury, including microvascular lesions. Most of the ongoing research on these lesions have focused on oxidative stress but have not found major molecular targets for the discovery of new treatment or early diagnosis. Herein, we have focused on elucidating the molecular mechanism(s) based on two new emerging molecules NRF1 and ID3, and how they may contribute to microvascular lesions in the lung and brain. Redox sensitive transcriptional activation of target genes depends on not only NRF1, but the recruitment of co-activators such as ID3 to the target gene promoter. Our review highlights the fact that targeting NRF1 and ID3 could be a promising therapeutic approach as they are major players in influencing cell growth, cell repair, senescence, and apoptotic cell death which contribute to vascular lesions. Knowledge about the molecular biology of these processes will be relevant for future therapeutic approaches to not only PAH but cerebral angiopathy and other vascular disorders. Therapies targeting transcription regulators NRF1 or ID3 have the potential for vascular disease-modification because they will address the root causes such as genomic instability and epigenetic changes in vascular lesions. We hope that our findings will serve as a stimulus for further research towards an effective treatment of microvascular lesions.

PDGF-BB promotes vascular smooth muscle cell migration by enhancing Pim-1 expression via inhibiting miR-214

Background

Several studies have indicated that the platelet-derived growth factor/platelet-derived growth factor receptor (PDGF/PDGFR) pathway is involved in the process of atherosclerosis. However, its underlying mechanism remains to be further elucidated. Serine/threonine-protein kinase pim-1 (Pim-1), a member of serine/threonine-specific kinases, is a pro-oncogene published to be related to cell proliferation, apoptosis, and metastasis of cancer cells. Whether Pim-1 is involved in PDGF/PDGFR pathway-mediated coronary atherosclerotic heart disease remains to be elucidated.

Methods

We established a cell model of PDGF-BB-stimulated smooth muscle cells using A7r5 cells. Transwell assay was used to detect the potential of cell migration and invasion. The targeted regulation of Pim-1 by miR-214 was confirmed by luciferase assay. Rescue experiments were performed to determine the role of the PDGF-BB/miR-214/Pim-1 axis on the cell migration of smooth muscle cells by including PDGF-BB treatment, and the overexpression of miR-214 and Pim-1. Quantitative polymerase chain reaction (qPCR) was used to examine the gene expression and western blot was performed to detect the protein expression.

Results

Our data indicated that PDGF-BB could effectively enhance smooth muscle cell migration. We also showed Pim-1 was a target of miR-214 in A7r5 cells. The expression of Pim-1 was shown to be upregulated by PDGF-BB via suppression of the expression of miR-214. Moreover, overexpression miR-214 inhibited PDGF-BB-stimulated Pim-1 expression and smooth muscle cell migration via modulating epithelial-mesenchymal transition (EMT), but no change on cell cycle. However, overexpression of Pim-1 reversed miR-214-blocked cell migration by promoting the activation of the STAT3, AKT, and ERK signaling pathways.

Conclusions

Our data suggested that the PDGF/miR-214/Pim-1 axis could be a potential target for coronary atherosclerotic heart disease.

Serumal Lipidomics Reveals the Anti-inflammatory Effect of Flax Lignans and Sinapic Acid in High-Fat-Diet-Fed Mice

Flax lignans (SDG) and sinapic acid (SA) both have the function of antioxidation and anti-inflammation. However, previous studies have focused mainly on biochemical measurements, gene expression analysis, and clinical assessments. There are limited studies that systematically reveal the underlying mechanism of the anti-inflammation effect of SDG or SA from the lipidomic point of view. Herein, the integrated lipidomic profiling platform was used for the analysis of free fatty acids (FFAs), phospholipids (PLs), triacylglycerols (TAGs), and oxylipins in high-fat (HF)-diet-fed mice after SDG or SA administration. Dietary supplementation of SDG or SA downregulated the levels of total TAGs and FFAs in the ApoE^-/- mice model. Furthermore, 28 potential lipids were screened out and considered as key evaluation factors to understand the anti-inflammation function and mechanism of SDG and SA. The results indicated that the anti-inflammatory effect of SDG and SA was principally exerted via regulation of lipid homeostasis.

Metabolic Syndrome in an Aging Society - Role of Oxidant-Antioxidant Imbalance and Inflammation Markers in Disentangling Atherosclerosis

INTRODUCTION

The prevalence of metabolic syndrome among the elderly population is growing. The elements of metabolic syndrome in an aging society are currently being researched. Atherosclerosis is a slow process in which the first symptoms may be observed after many years. The mechanisms underlying the progression of atherosclerosis are oxidative stress and inflammation. Inflammation and oxidative stress are associated with the increased incidence of metabolic syndrome. Taking the above into consideration, metabolic syndrome is thought to be a clinical equivalent of atherosclerosis.

AIM

The aim of this paper is to review the impact of the interplay of oxidant-antioxidant and inflammation markers in metabolic syndrome in general as well as its components in the pathophysiology which underlies development of atherosclerosis in elderly individuals.

METHODS

A systematic scan of online resources designed for elderly (≥65 years) published from 2005 to the end of 2020 were reviewed. This was supplemented with grey literature and then all resources were narratively analyzed. The analysis included the following terms: "atherosclerosis or metabolic syndrome" and "oxidative stress or inflammation" and "elderly" to find reports of atherosclerotic disease from asymptomatic to life-threatening among the elderly population with metabolic syndrome .

RESULTS

The work summarizes articles that were applicable to this study, including systematic reviews, qualitative studies and opinion pieces. Current knowledge focuses on monitoring the inflammation and oxidant-antioxidant imbalance in disentangling atherosclerosis in patients diagnosed with metabolic syndrome. The population-based studies described inflammation, increased oxidative stress and weak antioxidant defense systems as the mechanisms underlying atherosclerosis development. Moreover, there are discussions that these targets could potentially be a point of intervention to reduce the development of atherosclerosis in the elderly, especially those with altered glucose and lipid metabolism. Specific markers may be used as an approach for the prevention and lifestyle modification of atherosclerotic disease in such population.

CONCLUSION

Metabolic syndrome and its components are important contributors in the progression of atherosclerotic disease in the elderly population but constant efforts should be made to broaden our knowledge of elderly groups who are the most susceptible for the development of atherosclerosis complications.

microRNAs involved in psoriasis and cardiovascular diseases

Psoriasis is a chronic inflammatory disease involving the skin. Both genetic and environmental factors play a pathogenic role in psoriasis and contribute to the severity of the disease. Psoriasis, in fact, has been associated with different comorbidities such as diabetes, metabolic syndrome, gastrointestinal or kidney diseases, cardiovascular disease (CVD), and cerebrovascular diseases (CeVD). Indeed, life expectancy in severe psoriasis is reduced by up to 5 years due to CVD and CeVD. Moreover, patients with severe psoriasis have a higher prevalence of traditional cardiovascular (CV) risk factors, including dyslipidemia, diabetes, smoking, and hypertension. Further, systemic inflammation is associated with oxidative stress increase and induces endothelial damage and atherosclerosis progression. Different miRNA have been already described in psoriasis, both in the skin tissues and in the blood flow, to play a role in the progression of disease. In this review, we will summarize and discuss the most important miRNAs that play a role in psoriasis and are also linked to CVD.

Pathophysiology of Atherosclerotic Plaque Development-Contemporary Experience and New Directions in Research

Atherosclerotic plaque is the pathophysiological basis of important and life-threatening diseases such as myocardial infarction. Although key aspects of the process of atherosclerotic plaque development and progression such as local inflammation, LDL oxidation, macrophage activation, and necrotic core formation have already been discovered, many molecular mechanisms affecting this process are still to be revealed. This minireview aims to describe the current directions in research on atherogenesis and to summarize selected studies published in recent years-in particular, studies on novel cellular pathways, epigenetic regulations, the influence of hemodynamic parameters, as well as tissue and microorganism (microbiome) influence on atherosclerotic plaque development. Finally, some new and interesting ideas are proposed (immune cellular heterogeneity, non-coding RNAs, and immunometabolism) which will hopefully bring new discoveries in this area of investigation.

Long non-coding RNA LOC285194 inhibits proliferation and migration but promoted apoptosis in vascular smooth muscle cells via targeting miR-211/PUMA and TGF-β1/S100A4 signal

Long non-coding RNA LOC285194 (LOC285194) has reported to regulate vascular smooth muscle cells (VSMCs) proliferation and apoptosis in vitro and in vivo. Here we aimed to determine the role of LOC285194 in the proliferation, migration and apoptosis of VSMCs and its underlying mechanisms. A7r5 cells were transfected with Lv-LOC285194 or control Lv-NC for 24-72 h, or small interfering RNA targeting S100A4 (S100A4 siRNA) for 24-48 h, or co-transfected with Lv-LOC285194 and PUMA siRNA for 72 h, or treated with miR-211 inhibitor or co-transfected with Lv-LOC285194 and miR-211 mimics for 72 h. A7r5 cells were also treated with transforming growth factor - β(TGF-β) (5 ng/ml) after Lv-LOC285194 transfection for 24 h. The relationship between LOC285194 and TGF-β was confirmed using luciferase reporter assay. Cell proliferation and cell apoptosis were analyzed by Cell Counting Kit-8 (CCK-8) assay, ELISA and TUNEL staining. LOC285194 and miR-211 expression were detected by qPCR assay. S100A4, pro-apoptotic and anti-apoptotic protein were detected by Western blot assay. LOC285194 inhibited cell proliferation, invasion and migration and promoted cell apoptosis accompanied by upregulation of PUMA and downregulation of miR-211 and S100A4. Targeting PUMA reversed the effect of LOC285194 on cell apoptosis and proliferation. miR-211 mimic inhibited LOC285194-induced PUMA upregulation and decreased LOC285194-induced cell apoptosis. TGF-β (5 ng/ml) treatment reversed S100A4 siRNA or LOC285194-induced S100A4 expression. Luciferase reporter assay showed that TGF-β was the target of LOC285194. LOC285194 inhibits proliferation and promoted apoptosis in vascular smooth muscle cells via targeting miR-211/PUMA signal; In addition, LOC285194 decreased cell invasion and migration by targeting TGF-β1/S100A4 signal.

MicroRNA-520c-3p targeting of RelA/p65 suppresses atherosclerotic plaque formation

Atherosclerosis is a chronic inflammatory disease, and it's the leading cause of death worldwide. Dysregulation of microRNAs (miRNAs) has been found to be associated with atherosclerosis. miR-520c-3p has been implicated in several types of cancer. However, little is known about the role of miR-520c-3p in atherosclerosis. In this study, we found that miR-520c-3p agomir decreased atherosclerotic plaque size, collagen content, the quantity of PCNA-positive cell and RelA/p65 expression of vascular smooth muscle cells (VSMCs) in the aortic valve of apoE^-/- mice in vivo. The possible mechanisms of the protective effects of miR-520c-3p on atherosclerotic mice were then investigated in VSMCs. in vitro experiments showed that miR-520c-3p expressions were significantly reduced in human aortic vascular smooth muscle cell (HASMCs) treated with platelet-derived growth factor (PDGF-BB). miR-520c-3p mimics repress PDGF-BB-mediated the proliferation, migration and decrease in the percentage of cells in G2/M phase, which was associated with downregulation of RelA/p65. Mechanistically, miRNA pull-down, luciferase reporter and mRNA stability assays confirmed miR-520c-3p mimics was able to directly target 3'-UTR of RelA/p65 mRNA and decreased half-life of RelA/p65 mRNA in HASMCs. Overexpression of RelA/p65 reversed the inhibition of cell proliferation induced by miR-520c-3p mimics in HASMCs. In conclusion, our findings suggest that miR-520c-3p inhibits PDGF-BB-mediated the proliferation and migration of HASMCs by targeting RelA/p65, which may provide potential therapeutic strategies in atherosclerosis treatment.

CTBP1‑AS2 inhibits proliferation and induces autophagy in ox‑LDL‑stimulated vascular smooth muscle cells by regulating miR‑195‑5p/ATG14

Atherosclerosis (AS) is a chronic progressive disease caused by injury and functional changes in vascular smooth muscle cells (VSMCs). Long non‑coding RNAs (lncRNAs) are pivotal regulators in AS development. The present study aimed to explore the roles and molecular mechanisms of lncRNA CTBP1‑AS2 in AS progression. A dual‑luciferase reporter assay confirmed that miR‑195‑5p is a downstream target miRNA of lncRNA CTBP1‑AS2 and miR‑195‑5p was increased in AS. The expression levels of miR‑195‑5p and CTBP1‑AS2 in the serums of patients with AS and human aorta vascular smooth muscle cells was increased or decreased, respectively, following treatment with oxidized low‑density lipoprotein (ox‑LDL). Functional experiments showed that the overexpression of lncRNA CTBP1‑AS2 inhibited the proliferation of HA‑VSMCs and promoted their autophagy following ox‑LDL treatment. This effect could be reversed by treatment with ROC‑325, the inhibitor of autophagy, or miR‑195‑5p mimics. Autophagy related 14 (ATG14) was identified to be a target of miR‑195‑5p, and lncRNA CTBP1‑AS2 promoted ATG14 expression by serving as a competing endogenous RNA of miR‑195‑5p. The present study revealed that lncRNA CTBP1‑AS2 may serve a role in AS by inhibiting the proliferation and promoting the autophagy of VSMCs through ATG14 modulation via miR‑195‑5p. These data may provide a novel therapeutic target for AS.