MicroRNA-217 attenuates intima-media complex thickness of ascending aorta measured by ultrasound bio-microscopy and inhibits inflammation and lipid metabolism in atherosclerotic models of ApoE-/- mice

Bacteroides fragilis Supplementation Deteriorated Metabolic Dysfunction, Inflammation, and Aorta Atherosclerosis by Inducing Gut Microbiota Dysbiosis in Animal Model

Background: The gut microbial ecosystem is an important factor that regulates host health and the onset of chronic diseases, such as inflammatory bowel diseases, obesity, hyperlipidemia, and diabetes mellitus, which are important risk factors for atherosclerosis. However, the links among diet, microbiota composition, and atherosclerotic progression are unclear. Methods and results: Four-week-old mice (^-/- mice, C57Bl/6) were randomly divided into two groups, namely, supplementation with culture medium (control, CTR) and Bacteroides fragilis (BFS), and were fed a high-fat diet. The gut microbiota abundance in feces was evaluated using the 16S rDNA cloning library construction, sequencing, and bioinformatics analysis. The atherosclerotic lesion was estimated using Oil Red O staining. Levels of CD36, a scavenger receptor implicated in atherosclerosis, and F4/80, a macrophage marker in small intestine, were quantified by quantitative real-time PCR. Compared with the CTR group, the BFS group showed increased food intake, fasting blood glucose level, body weight, low-density lipoprotein level, and aortic atherosclerotic lesions. BFS dramatically reduced Lactobacillaceae (LAC) abundance and increased Desulfovibrionaceae (DSV) abundance. The mRNA expression levels of CD36 and F4/80 in small intestine and aorta tissue in the BFS group were significantly higher than those in the CTR group. Conclusions: gut microbiota dysbiosis was induced by BFS. It was characterized by reduced LAC and increased DSV abundance and led to the deterioration of glucose/lipid metabolic dysfunction and inflammatory response, which likely promoted aorta plaque formation and the progression of atherosclerosis.

Increased Intima-Media Thickness of the Ascending Aorta May Predict Neurological Complications Associated with TAVI

OBJECTIVES

Neurological complications associated with transcatheter aortic valve implantation (TAVI) are important due to its morbidity and mortality risks. The purpose of this study was to investigate the importance of the features of the aortic valve and ascending aorta to predict the neurological complications associated with TAVI.

METHODS

The patients for whom the heart team decided to perform TAVI were included in the study. In order to assess possible neurological complications, cerebral diffusionweighted magnetic resonance imaging(MRI) was performed pre- and post-operatively. The diameter of the patients' aortic root and ascending aorta, aortic valve scores, intima media thickness of the ascending aorta were measured from their transesophageal echocardiography records.

RESULTS

A total of 108 patients constituted the study population. 31 patients were found to develop a new lesion (MR+) detected on MRI after TAVI, while 76 patients did not have any new lesions (MR-). The groups did not have any significant differences in their aortic valve features and scores. However, AA-IMT was found to be higher in the MR+ group (1.8mm [1.6-2.3] vs 1.4mm [1.2-1.8] interquartile range). The multivariate logistic regression analysis conducted to detect new lesions revealed that AA-IMT led to a significantly increased risk.

CONCLUSION

The features of the ascending are more important than the demographic characteristics of patients and features of the native valve in predicting new lesions on MRI scans and thus neurological events after TAVI.

Recent advances in the regulation of ABCA1 and ABCG1 by lncRNAs

Coronary heart disease (CHD) with atherosclerosis is the leading cause of death worldwide. ABCA1 and ABCG1 promote cholesterol efflux to suppress foam cell generation and reduce atherosclerosis development. Long noncoding RNAs (lncRNAs) are emerging as a unique group of RNA transcripts that longer than 200 nucleotides and have no protein-coding potential. Many studies have found that lncRNAs regulate cholesterol efflux to influence atherosclerosis development. ABCA1 is regulated by different lncRNAs, including MeXis, GAS5, TUG1, MEG3, MALAT1, Lnc-HC, RP5-833A20.1, LOXL1-AS1, CHROME, DAPK1-IT1, SIRT1 AS lncRNA, DYNLRB2-2, DANCR, LeXis, LOC286367, and LncOR13C9. ABCG1 is also regulated by different lncRNAs, including TUG1, GAS5, RP5-833A20.1, DYNLRB2-2, ENST00000602558.1, and AC096664.3. Thus, various lncRNAs are associated with the roles of ABCA1 and ABCG1 on cholesterol efflux in atherosclerosis regulation. However, some lncRNAs play dual roles in ABCA1 expression and atherosclerosis, and the functions of some lncRNAs in atherosclerosis have not been investigated in vivo. In this article, we review the roles of lncRNAs in atherosclerosis and focus on new insights into lncRNAs associated with the roles of ABCA1 and ABCG1 on cholesterol efflux and the potential of these lncRNAs as novel therapeutic targets in atherosclerosis.

miR-217 alleviates high-glucose-induced vascular smooth muscle cell dysfunction via regulating ROCK1

MicroRNA-217 (miR-217) has been recently reported to be abnormally expressed during atherosclerosis. Nonetheless, it still remains unknown whether miR-217 can regulate inflammation, proliferation, migration, and apoptosis of vascular smooth muscle cells (VSMCs) in high-glucose condition. Sprague Dawley rats were used for establishing diabetic animal models. miR-217 mimics and miR-217 inhibitors were transfected into VSMCs. The miR-217 and ROCK1 expressions were measured by quantitative reverse transcription-polymerase chain reaction and Western blot. VSMCs' proliferation, migration, cell cycle, and apoptosis were validated using the Cell Counting Kit-8 assay, Transwell assay, and flow cytometry analysis, respectively. The binding sites between miR-217 and the 3'-untranslated region of ROCK1 were predicted via miRanda, PicTar, TargetScan, and microT databases, and the targeting relationship was confirmed by dual-luciferase reporter experiments. miR-217 was found to be upregulated in VSMCs treated by high glucose and aorta VSMCs of diabetic rats. Transfection of miR-217 mimics significantly induced VSMCs cycle arrest, inhibition of proliferation, reduction of migration, and enhancement of apoptosis. The bioinformatics analysis and dual-luciferase reporter experiments identified ROCK1 as a direct target of miR-217. miR-217 inhibits excessive proliferation and migration of VSMCs induced by high glucose by targeting ROCK1.

MicroRNA-217 modulates inflammation, oxidative stress, and lung injury in septic mice via SIRT1

Inflammation and oxidative stress contribute to the initiation and progression of septic lung injury. MicroRNA-217 (miR-217) is proved to be involved in controlling inflammatory response and oxidative stress, yet its role and underlying mechanism in the pathogenesis of septic lung injury remain elusive. Caecal ligation and puncture surgery were performed to generate sepsis in vivo and mice were kept for 12 h to imitate septic lung injury. Next, mice were administrated with miR-217 antagomir or agomir to decrease or increase the expression of miR-217 in lung tissue. Moreover, primary peritoneal macrophages were separated and incubated with lipopolysaccharide (LPS) to further verify the role of miR-217 in vitro. miR-217 was upregulated in septic lungs and primary macrophages. miR-217 antagomir alleviated, whereas miR-217 agomir aggravated inflammation and oxidative stress in septic mice and LPS-stimulated macrophages. Further detection identified SIRT1 was responsible for miR-217 antagomir-mediated anti-inflammatory and anti-oxidant effects, and SIRT1 inhibition abolished the beneficial effects of miR-217 antagomir in vivo and in vitro. Our data defined miR-217 as a therapeutic target for treating septic lung injury.

Serum MicroRNA on inflammation: a literature review of mouse model studies

MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate target gene expression by binding to sequences in messenger RNA processing. Inflammation is a protective reaction from harmful stimuli. MiRNAs can be biomarkers of diseases related to inflammation and are widely expressed in serum. However, overall changes in serum miRNA levels during inflammation have yet to be observed. Here, we selected studies published until 20 January 2020 that examined miRNAs in mouse models of inflammation. Serum microRNA, inflammation, inflammatory and mouse were used as search terms to select articles from PubMed and MEDLINE. Among the articles, sepsis and 18 related miRNAs were mainly examined. Eleven miRNAs were related to brain disease and 10 with fibrosis. Seventeen injury-induced inflammatory disease studies were included, as well as other inflammatory diseases, such as metabolic disease, vascular disease, arthritis, asthma, autoimmune disease, inflammatory bowel disease, and thyroiditis. The data described miRNA-associated downstream pathways associated with inflammation as well as mitochondrial responses, oxidative responses, apoptosis, cell signalling, and cell differentiation. We expect that the data will inform future animal inflammation-related miRNA studies.

MicroRNA-217 ameliorates inflammatory damage of endothelial cells induced by oxidized LDL by targeting EGR1

Oxidized low-density lipoprotein (ox-LDL) modulates gene transcription and expression and induces the development of endothelium inflammation and endothelial dysfunction, in which microRNAs (miRNAs) play a crucial role. However, the mechanism of ox-LDL in inflammatory damage of endothelial cells still remains elusive. Herein, we focused on the effect of hsa-miR-217-5p (miR-217) on endothelial dysfunction induced by ox-LDL by targeting early growth response protein-1 (EGR1). In the present study, 31 upregulated miRNAs and 59 downregulated miRNAs (Fold Change > 2, P value < 0.05) were identified after 6 h of 80 μg/mL ox-LDL exposure in human aortic endothelial cells (HAECs) by small RNA sequencing, including miR-217 that was significantly decreased (FC = 0.2787, P value = 5.22E-16). MiR-217 knockdown inhibited cell proliferation and increased level of IL-6, IL-1β, ICAM-1 and TNF-α, while overexpression of miR-217 relieved the growth inhibition induced by ox-LDL and demonstrated anti-inflammatory effect in HAECs. EGR1 was predicted as a potential candidate target gene of miR-217 by TargetScan. The subsequent dual-luciferase reporter assay confirmed the direct binding of miR-217 to 3'UTR of EGR1. And EGR1 expression was negatively correlated with the level of miRNA-217 in HAECs after exposure to ox-LDL. Overexpression of EGR1 recapitulated the effects of miR-217 knockdown on cell proliferation inhibition and inflammation in HAECs, while knockdown EGR1 relieved the proliferative inhibition and demonstrated anti-inflammatory effect in ox-LDL-induced HAECs. The present study confirmed miR-217 ameliorates inflammatory damage of endothelial cells induced by oxidized LDL by targeting EGR1.

MicroRNA sequences modulating inflammation and lipid accumulation in macrophage “foam” cells: Implications for atherosclerosis

Accumulation of macrophage “foam” cells, laden with cholesterol and cholesteryl ester, within the intima of large arteries, is a hallmark of early “fatty streak” lesions which can progress to complex, multicellular atheromatous plaques, involving lipoproteins from the bloodstream and cells of the innate and adaptive immune response. Sterol accumulation triggers induction of genes encoding proteins mediating the atheroprotective cholesterol efflux pathway. Within the arterial intima, however, this mechanism is overwhelmed, leading to distinct changes in macrophage phenotype and inflammatory status. Over the last decade marked gains have been made in understanding of the epigenetic landscape which influence macrophage function, and in particular the importance of small non-coding micro-RNA (miRNA) sequences in this context. This review identifies some of the miRNA sequences which play a key role in regulating “foam” cell formation and atherogenesis, highlighting sequences involved in cholesterol accumulation, those influencing inflammation in sterol-loaded cells, and novel sequences and pathways which may offer new strategies to influence macrophage function within atherosclerotic lesions.

SR-BI as a target of natural products and its significance in cancer

Scavenger receptor class B type I (SR-BI) protein is an integral membrane glycoprotein. SR-BI is emerging as a multifunctional protein, which regulates autophagy, efferocytosis, cell survival and inflammation. It is well known that SR-BI plays a critical role in lipoprotein metabolism by mediating cholesteryl esters selective uptake and the bi-directional flux of free cholesterol. Recently, SR-BI has also been identified as a potential marker for cancer diagnosis, prognosis, or even a treatment target. Natural products are a promising source for the discovery of new drug leads. Multiple natural products were identified to regulate SR-BI protein expression. There are still a number of challenges in modulating SR-BI expression in cancer and in using natural products for modulation of such protein expression. In this review, our purpose is to discuss the relationship between SR-BI protein and cancer, and the molecular mechanisms regulating SR-BI expression, as well as to provide an overview of natural products that regulate SR-BI expression.

Diagnostic and theranostic microRNAs in the pathogenesis of atherosclerosis

MicroRNAs (miRNAs) are a group of small single strand and noncoding RNAs that regulate several physiological and molecular signalling pathways. Alterations of miRNA expression profiles may be involved with pathophysiological processes underlying the development of atherosclerosis and cardiovascular diseases, including changes in the functions of the endothelial cells and vascular smooth muscle cells, such as cell proliferation, migration and inflammation, which are involved in angiogenesis, macrophage function and foam cell formation. Thus, miRNAs can be considered to have a crucial role in the progression, modulation and regulation of every stage of atherosclerosis. Such potential biomarkers will enable us to predict therapeutic response and prognosis of cardiovascular diseases and adopt effective preclinical and clinical treatment strategies. In the present review article, the current data regarding the role of miRNAs in atherosclerosis were summarized and the potential miRNAs as prognostic, diagnostic and theranostic biomarkers in preclinical and clinical studies were further discussed. The highlights of this review are expected to present opportunities for future research of clinical therapeutic approaches in vascular diseases resulting from atherosclerosis with an emphasis on miRNAs.

MicroRNA‑217 is involved in the progression of atherosclerosis through regulating inflammatory responses by targeting sirtuin 1

Atherosclerosis is a chronic inflammatory disease, and it is a global clinical problem. The development of new and effective therapeutic targets for atherosclerosis is necessary. A number of microRNAs (miRNAs) have been demonstrated to serve a crucial role in atherosclerosis. However, the role of miRNA (miR)-217 in atherosclerosis remains unclear. Therefore, the aim of the present study was to investigate the role and mechanism of miR-217 in atherosclerosis. The level of miR-217 was detected in the blood of patients with atherosclerosis using reverse transcription-quantitative PCR. THP-1 acute monocytic leukemia cells were treated with oxidized low-density lipoprotein (ox-LDL) to develop an atherosclerotic cell model of macrophages. The relationship between miR-217 and sirtuin 1 (SIRT1) was determined by TargetScan and dual luciferase reporter assay. Cell apoptosis was measured by flow cytometry. Production of pro-inflammatory factors and triglyceride (TG) and total cholesterol (TC) levels were also determined. The results demonstrated that miR-217 was significantly upregulated in atherosclerosis. SIRT1 was demonstrated to be a direct target of miR-217 and was downregulated in atherosclerosis. Downregulation of miR-217 significantly inhibited ox-LDL-induced TG and TC level increase, cell apoptosis and the upregulation of the pro-inflammatory factors tumor necrosis factor α, interleukin (IL)-6 and IL-1β. Additionally, the SIRT1/AMP-activated protein kinase α/NF-κB pathway was at least partially involved in modulating the effects of miR-217 inhibition on THP-1 cells treated with ox-LDL. In addition, the effects of miR-217 downregulation on ox-LDL-treated THP-1 cells were eliminated by SIRT1 silencing. In conclusion, the results of the present study indicated that miR-217 downregulation may relieve atherosclerosis through the inhibition of macrophage apoptosis and inflammatory response by targeting SIRT1.

miRNA-335-5p relieves chondrocyte inflammation by activating autophagy in osteoarthritis

AIMS

Osteoarthritis (OA) is a chronic and degenerative joint disease prevalent in the elderly, which is characterized by hypertrophy and reactive hyperplasia of articular cartilage. Autophagy has been reported to inhibit inflammation and reduce chondrocyte apoptosis in OA. As the microRNA (miRNA)-335-5p has been linked to both inflammation and autophagy, this study aimed to investigate its potential role in regulating autophagy during the pathogenesis of OA.

MAIN METHODS

Quantitative real-time PCR (qRT-PCR) was used to detect miRNA-335-5p expression in normal and OA human chondrocytes. Following transfection of human OA chondrocytes with double-stranded miRNA-335-5p mimic/inhibitor, qRT-PCR, western blotting, and immunofluorescence were used to determine expression levels of the inflammatory mediators IL-1β, IL-6, and TNF-α, and the autophagic markers Beclin-1, autophagy-related protein 5 (ATG5), and ATG7. The autophagy inhibitor 3-methyladenine (3-MA) was used to link the anti-inflammatory effects of miRNA-335-5p to autophagy.

KEY FINDINGS

The expression of miRNA-335-5p was significantly lower in OA chondrocytes than in normal chondrocytes. Transfection of human OA chondrocytes with the miRNA-335-5p mimic led to a remarkable increase in viability, a significant increase in autophagy-related factors, and a reduction in inflammatory mediators. Importantly, treatment of miRNA-335-5p-overexpressing OA chondrocytes with the autophagy inhibitor 3-MA restored the expression of inflammatory mediators.

SIGNIFICANCE

We conclude that miRNA-335-5p can significantly alleviate inflammation in human OA chondrocytes by activating autophagy. Therefore, miRNA-335-5p has potential for future use in the clinical diagnosis and treatment of OA.

Cinnamaldehyde attenuates atherosclerosis via targeting the IκB/NF-κB signaling pathway in high fat diet-induced ApoE−/− mice

Cinnamaldehyde is a flavor isolated from the bark of Cinnamomum cassia Presl and exerts anti-inflammation effects in various diseases.

Molecular mechanisms and genetic regulation in atherosclerosis

Atherosclerosis (AS) manifested by lipid accumulation, extracellular matrix protein deposition, and calcification in the intima and media of the large to medium size arteries promoting arterial stiffness and reduction of elasticity. It has been accepted that AS leads to increased morbidity and mortality worldwide. Recent studies indicated that genetic abnormalities play an important role in the development of AS. Specific genetic mutation and histone modification have been found to induce AS formation. Furthermore, specific RNAs such as microRNAs and circular RNAs have been identified to play a crucial role in the progression of AS. Nevertheless, the mechanisms by which genetic mutation, DNA and histone modification, microRNAs and circular RNA induce AS still remain elusive. This review describes specific mechanisms and pathways through which genetic mutation, DNA and histone modification, microRNAs and circular RNA instigate AS. This review further provides a therapeutic strategic direction for the treatment of AS targeting genetic mechanisms.

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DNA and histone modifications promote transcriptional changes in atherosclerosis.

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Gene mutations cause dyslipidemia and hyperglycemia to promote atherosclerosis.

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miRNAs and cirRNA are involved in the development of atherosclerosis.

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Gene mutations associated oxidative stress and altered inflammatory and nutritive factors promote atherosclerosis.