Downregulation of microRNA-135b promotes atherosclerotic plaque stabilization in atherosclerotic mice by upregulating erythropoietin receptor

miR-135b: An emerging player in cardio-cerebrovascular diseases

miR-135 is a highly conserved miRNA in mammals and includes miR-135a and miR-135b. Recent studies have shown that miR-135b is a key regulatory factor in cardio-cerebrovascular diseases. It is involved in regulating the pathological process of myocardial infarction, myocardial ischemia/reperfusion injury, cardiac hypertrophy, atrial fibrillation, diabetic cardiomyopathy, atherosclerosis, pulmonary hypertension, cerebral ischemia/reperfusion injury, Parkinson's disease, and Alzheimer's disease. Obviously, miR-135b is an emerging player in cardio-cerebrovascular diseases and is expected to be an important target for the treatment of cardio-cerebrovascular diseases. However, the crucial role of miR-135b in cardio-cerebrovascular diseases and its underlying mechanism of action has not been reviewed. Therefore, in this review, we aimed to comprehensively summarize the role of miR-135b and the signaling pathway mediated by miR-135b in cardio-cerebrovascular diseases. Drugs targeting miR-135b for the treatment of diseases and related patents, highlighting the importance of this target and its utility as a therapeutic target for cardio-cerebrovascular diseases, have been discussed.

A Review of MicroRNAs and lncRNAs in Atherosclerosis as Well as Some Major Inflammatory Conditions Affecting Atherosclerosis

It is generally accepted that atherosclerosis is a chronic inflammatory disease. The link between atherosclerosis and other inflammatory diseases such as psoriasis, type 2 diabetes mellitus (T2DM), and rheumatoid arthritis (RA) via metabolic, inflammatory, and immunoregulatory pathways is well established. The aim of our review was to summarize the associations between selected microRNAs (miRs) and long non-coding RNAs (lncRNAs) and atherosclerosis, psoriasis, T2DM, and RA. We reviewed the role of miR-146a, miR-210, miR-143, miR-223, miR-126, miR-21, miR-155, miR-145, miR-200, miR-133, miR-135, miR-221, miR-424, let-7, lncRNA-H19, lncRNA-MEG3, lncRNA-UCA1, and lncRNA-XIST in atherosclerosis and psoriasis, T2DM, and RA. Extracellular vesicles (EVs) are a method of intracellular signal transduction. Their function depends on surface expression, cargo, and the cell from which they originate. The majority of the studies that investigated lncRNAs and some miRs had relatively small sample sizes, which limits the generalizability of their findings and indicates the need for more research. Based on the studies reviewed, miR-146a, miR-155, miR-145, miR-200, miR-133, and lncRNA-H19 are the most promising potential biomarkers and, possibly, therapeutic targets for atherosclerosis as well as T2DM, RA, and psoriasis.

CircZNF609 sponges miR-135b to up-regulate SEMA3A expression to alleviate ox-LDL-induced atherosclerosis

The initiation and progression of atherosclerotic plaque caused by abnormal lipid metabolism is one of the main causes of atherosclerosis (AS). Lipid droplet accumulation has become a novel research pointcut for AS treatment in recent years. In AS patients, miR-135b level was up-regulated relative to the normal cases, which showed negative correlations with the levels of Semaphorin 3A (SEMA3A) and circZNF609, separately. The U937-derived macrophages were cultured with ox-LDL to establish AS models in vitro. After that, the lipid accumulation, inflammation, mitochondrial dysfunction and cell death were evaluated by ORO, ELISA, RT-qPCR, western blot, JC-1 and FCM assays respectively. Transfection of the circZNF609 expression vector notably declined lipid accumulation, attenuated inflammation, reduced mitochondrial dysfunction and inhibited cell death in ox-LDL-stimulated cells. The direct binding of miR-135b to circZNF609 in vitro was confirmed using RIP assay, and SEMA3A expression was up-regulated by circZNF609 overexpression. After manipulating the endogenous expressions of circZNF609, miR-135b and SEMA3A, the above damages in ox-LDL-stimulated cells were rescued by inhibition of miR-135b expression and overexpression of circZNF609 or SEMA3A. Besides, the AS mice model was built to demonstrate the excessive lipid accumulation, increasing inflammation and cell death in AS pathogenesis according to the results of HE staining, ELISA and IHC assays, while these damages were reversed after overexpression of circZNF609 or SEMA3A. In AS models, overexpressed circZNF609 prevents the AS progression through depleting miR-135b expression and subsequent up-regulation of SEMA3A expression to overwhelm lipid accumulation, mitochondrial dysfunction and cell death.

A UHPLC-Q-TOF-MS-based serum and urine metabolomics approach reveals the mechanism of Gualou-Xiebai herb pair intervention against atherosclerosis process in ApoE-/- mice

Atherosclerosis (AS) is a metabolic disorder commonly correlated with a high-fat diet (HFD). There are many endogenous metabolic changes associated with AS development. Gualou-Xiebai (GLXB) is a traditional Chinese medicine herb pair that has been used to treat AS. However, the mechanism of GLXB herb pair on the process of AS is still essentially unknown. In this study, aortic histopathological examination and biochemical analyses were used to validate the anti-atherosclerotic effects of GLXB herb pair on ApoE^-/- mice during the disease course of AS. The mechanism of GLXB herb pair were performed by metabolomics approach based on ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). As a result, GLXB herb pair has protective effects on AS lesion development and improves blood lipid levels in ApoE^-/- mice. A total of 34, 39, and 49 metabolites were found to be profoundly altered in the 9-week, 14-week, and 19-week model groups compared with the corresponding control groups. Among them, 16, 18, and 18 metabolites showed a trend toward normal levels after pharmacological intervention. Metabolic pathway analysis found that GLXB herb pair mainly affects glycerophospholipid metabolism, pentose and glucuronate interconversions in 9 weeks; linoleic acid metabolism, cysteine and methionine metabolism, and arachidonic acid metabolism in 14 weeks; arachidonic acid metabolism and pentose and glucuronate interconversions in 19 weeks. The results demonstrated that GLXB herb pair mainly played a therapeutic role by regulating glycerophospholipid metabolism and pentose and glucuronate interconversions in the whole process of AS.

miRNA-29a inhibits atherosclerotic plaque formation by mediating macrophage autophagy via PI3K/AKT/mTOR pathway

Background: miR-29a plays a vital role in AS, but the relationship between the miR-29a-targeted PI3K signaling pathway and AS remains unclear. Therefore, this study was carried out.

Methods: Gene expression profiles from the GEO database containing AS samples were analyzed. ApoE^−/− mice and RAW264.7 cells were treated with miR-29a negative control (NC), miR-29a mimic and miR-29a inhibitor to establish the AS model. Then MOVAT staining, TEM, Western blotting, and immunofluorescence staining were adopted for testing target proteins.

Results: DEGs were identified from GSE137578, GSE132651, GSE113969, GSE43292, and GSE97210 datasets. It was found that there were targeted binding sites between miR-29a and PIK3CA. Besides, GO and KEGG analysis demonstrated that autophagy was an enriched pathway in AS. Later, PPI network was depicted, and hub genes were then determined. The results revealed that miR-29a suppressed the areas of plaques and lesional macrophages, but had no impact on VSMCs. TEM results showed the organelles pyknosis of lesional macrophages damaged morphological changes. Furthermore, miR-29a amplified the M2-like macrophages but suppressed the polarization of M1-like macrophages in atherosclerotic plaques. According to mouse and RAW 264.7 cell experiments, miR-29a significantly inhibited the protein expressions of PI3K, p-PI3K, p-AKT, and p-mTOR, which were consistent with the increased expressions of autophagy-related proteins, Beclin 1 and LC3II. However, the miR-29a suppression exhibited the contrary results.

Conclusion: MiR-29a elevation induces the increase of autophagy by down-regulating the PI3K/AKT/mTOR pathway in the progression of AS, indicating that miR-29a is a novel therapeutic strategy for AS.

Particulate Matter-Induced Acute Coronary Syndrome: MicroRNAs as Microregulators for Inflammatory Factors

The most prevalent cause of mortality and morbidity worldwide is acute coronary syndrome (ACS) and its consequences. Exposure to particulate matter (PM) from air pollution has been shown to impair both. Various plausible pathogenic mechanisms have been identified, including microRNAs (miRNAs), an epigenetic regulator for gene expression. Endogenous miRNAs, average 22-nucleotide RNAs (ribonucleic acid), regulate gene expression through mRNA cleavage or translation repression and can influence proinflammatory gene expression posttranscriptionally. However, little is known about miRNA responses to fine PM (PM_2.5, PM₁₀, ultrafine particles, black carbon, and polycyclic aromatic hydrocarbon) from air pollution and their potential contribution to cardiovascular consequences, including systemic inflammation regulation. For the past decades, microRNAs (miRNAs) have emerged as novel, prospective diagnostic and prognostic biomarkers in various illnesses, including ACS. We wanted to outline some of the most important studies in the field and address the possible utility of miRNAs in regulating particulate matter-induced ACS (PMIA) on inflammatory factors in this review.

Untargeted Metabolomic Profiling of Cuprizone-Induced Demyelination in Mouse Corpus Callosum by UPLC-Orbitrap/MS Reveals Potential Metabolic Biomarkers of CNS Demyelination Disorders

Multiple sclerosis (MS) is a neurodegenerative disorder characterized by periodic neuronal demyelination, which leads to a range of symptoms and eventually to disability. The goal of this research was to use UPLC-Orbitrap/MS to identify validated biomarkers and explore the metabolic mechanisms of MS in mice. Thirty-two C57BL/6 male mice were randomized into two groups that were fed either normal food or 0.2% CPZ for 11 weeks. The mouse demyelination model was assessed by LFB and the expression of MBP by immunofluorescence and immunohistochemistry. The metabolites of the corpus callosum were quantified using UPLC-Orbitrap/MS. The mouse pole climbing experiment was used to assess coordination ability. Multivariate statistical analysis was adopted for screening differential metabolites, and the ingenuity pathway analysis (IPA) was used to reveal the metabolite interaction network. We successfully established the demyelination model. The CPZ group slowly lost weight and showed an increased pole climbing time during feeding compared to the CON group. A total of 81 metabolites (VIP > 1 and P < 0.05) were determined to be enriched in 24 metabolic pathways; 41 metabolites were markedly increased, while 40 metabolites were markedly decreased in the CPZ group. The IPA results revealed that these 81 biomarker metabolites were associated with neuregulin signaling, PI3K-AKT signaling, mTOR signaling, and ERK/MAPK signaling. KEGG pathway analysis showed that two significantly different metabolic pathways were enriched, namely, the glycerophospholipid and sphingolipid metabolic pathways, comprising a total of nine biomarkers. Receiver operating characteristic analysis showed that the metabolites (e.g., PE (16 : 0/22 : 6(4Z, 7Z, 10Z, 13Z, 16Z, 19Z)), PC (18 : 0/22 : 4(7Z, 10Z, 13Z, 16Z)), cytidine 5′-diphosphocholine, PS (18 : 0/22 : 6(4Z, 7Z, 10Z, 13Z, 16Z, 19Z)), glycerol 3-phosphate, SM (d18 : 0/16 : 1(9Z)), Cer (d18:1/18 : 0), galabiosylceramide (d18:1/18 : 0), and GlcCer (d18:1/18 : 0)) have good discrimination ability for the CPZ group. In conclusion, the differential metabolites have great potential to serve as biomarkers of demyelinating diseases. In addition, we identified metabolic pathways associated with CPZ-induced demyelination pathogenesis, which provided a new perspective for understanding the relationship between metabolites and CNS demyelination pathogenesis.

miR-135a Suppresses Granulosa Cell Growth by Targeting Tgfbr1 and Ccnd2 during Folliculogenesis in Mice

The success of female reproduction relies on high quality oocytes, which is determined by well-organized cooperation between granulosa cells (GCs) and oocytes during folliculogenesis. GC growth plays a crucial role in maintaining follicle development. Herein, miR-135a was identified as a differentially expressed microRNA in pre-ovulatory ovarian follicles between Large White and Chinese Taihu sows detected by Solexa deep sequencing. We found that miR-135a could significantly facilitate the accumulation of cells arrested at the G1/S phase boundary and increase apoptosis. Mechanically, miR-135a suppressed transforming growth factor, beta receptor I (Tgfbr1) and cyclin D2 (Ccnd2) expression by targeting their 3′UTR in GCs. Furthermore, subcellular localization analysis and a chromatin immunoprecipitation-quantitative real-time PCR (ChIP-qPCR) assay demonstrated that the TGFBR1-SMAD3 pathway could enhance Ccnd2 promoter activity and thus upregulate Ccnd2 expression. Finally, estrogen receptor 2 (ESR2) functioned as a transcription factor by directly binding to the miR-135a promoter region and decreasing the transcriptional activity of miR-135a. Taken together, our study reveals a pro-survival mechanism of ESR2/miR-135a/Tgfbr1/Ccnd2 axis for GC growth, and also provides a novel target for the improvement of female fertility.

Therapies Targeted at Non-Coding RNAs in Prevention and Limitation of Myocardial Infarction and Subsequent Cardiac Remodeling-Current Experience and Perspectives

Myocardial infarction is one of the major causes of mortality worldwide and is a main cause of heart failure. This disease appears as a final point of atherosclerotic plaque progression, destabilization, and rupture. As a consequence of cardiomyocytes death during the infarction, the heart undergoes unfavorable cardiac remodeling, which results in its failure. Therefore, therapies aimed to limit the processes of atherosclerotic plaque progression, cardiac damage during the infarction, and subsequent remodeling are urgently warranted. A hopeful therapeutic option for the future medicine is targeting and regulating non-coding RNA (ncRNA), like microRNA, circular RNA (circRNA), or long non-coding RNA (lncRNA). In this review, the approaches targeted at ncRNAs participating in the aforementioned pathophysiological processes involved in myocardial infarction and their outcomes in preclinical studies have been concisely presented.

CircRNA RSF1 regulated ox-LDL induced vascular endothelial cells proliferation, apoptosis and inflammation through modulating miR-135b-5p/HDAC1 axis in atherosclerosis

Background

Atherosclerosis (AS) is the most common type in cardiovascular disease. Due to its complex pathogenesis, the exact etiology of AS is unclear. circRNA has been shown to play an essential role in most diseases. However, the underlying mechanism of circRNA in AS has been not understood clearly.

Methods

Quantitative Real-Time PCR assay was used to detect the expression of circRSF1, miR-135b-5p and histone deacetylase 1 (HDAC1). Western blot was applied to the measure of protein expression of HDAC1, B-cell lymphoma-2 (Bcl-2), BCL2-associated X (Bax), cleaved-caspase-3, vascular cell adhesion molecule 1 (VCAM1), intercellular cell adhesion molecule-1 (ICAM1) and E-selectin. MTT assay and flow cytometry were used to detect cell proliferation and apoptosis, respectively. Dual luciferase reporter assay and RIP assay was used to determine the relationship among circRSF1, miR-135b-5p and HDAC1. Besides, an ELISA assay was performed to measure the levels of IL-1β, IL-6, TNF-α and IL-8.

Results

In this study, ox-LDL inhibited circRSF1 and HDAC1 expression while upregulated miR-135b-5p expression in Human umbilical vein endothelial cells (HUVECs). Importantly, ox-LDL could inhibit HUVECs growth. Moreover, promotion of circRSF1 or inhibition of miR-135b-5p induced cell proliferation while inhibited apoptosis and inflammation of ox-LDL-treated HUVECs, which was reversed by upregulating miR-135b-5p or downregulating HDCA1 in ox-LDL-treated HUVECs. More than that, we verified that circRSF1 directly targeted miR-135b-5p and HDAC1 was a target mRNA of miR-135b-5p in HUVECs.

Conclusion

CircRSF1 regulated ox-LDL-induced vascular endothelial cell proliferation, apoptosis and inflammation through modulating miR-135b-5p/HDAC1 axis in AS, providing new perspectives and methods for the treatment and diagnosis of AS.

Role of PI3K in the Progression and Regression of Atherosclerosis

Phosphatidylinositol 3 kinase (PI3K) is a key molecule in the initiation of signal transduction pathways after the binding of extracellular signals to cell surface receptors. An intracellular kinase, PI3K activates multiple intracellular signaling pathways that affect cell growth, proliferation, migration, secretion, differentiation, transcription and translation. Dysregulation of PI3K activity, and as aberrant PI3K signaling, lead to a broad range of human diseases, such as cancer, immune disorders, diabetes, and cardiovascular diseases. A growing number of studies have shown that PI3K and its signaling pathways play key roles in the pathophysiological process of atherosclerosis. Furthermore, drugs targeting PI3K and its related signaling pathways are promising treatments for atherosclerosis. Therefore, we have reviewed how PI3K, an important regulatory factor, mediates the development of atherosclerosis and how targeting PI3K can be used to prevent and treat atherosclerosis.

Apoptosis, autophagy and atherosclerosis: Relationships and the role of Hsp27

Atherosclerosis is a multifactorial chronic inflammatory disease of the arterial wall, and an important pathological basis of coronary heart disease. Endothelial cells, vascular smooth muscle cells, and macrophages play important roles in the development of atherosclerosis. Of note, apoptosis and autophagy, two types of programmed cell death, influence the development and progression of atherosclerosis via the modulation of such cells. The small heat shock protein Hsp27 is a multifunctional protein induced by various stress factors and has a protective effect on cells. A large number of studies have demonstrated that Hsp27 plays an important role in regulating apoptosis. Recently, some studies have suggested that Hsp27 also participates in the autophagic process. Moreover, Hsp27 is closely related to the occurrence and development of atherosclerosis. Here, we summarize the molecular mechanisms of apoptosis and autophagy and discuss their effects on endothelial cells, vascular smooth muscle cells, and macrophages in the context of atherosclerotic procession. We further explore the involvement of Hsp27 in apoptosis, autophagy, and atherosclerosis. We speculate that Hsp27 may exert its anti-atherosclerotic role via the regulation of apoptosis and autophagy; this may provide the basis for the development of new approaches for the prevention and treatment of atherosclerosis.

Unveiling ncRNA regulatory axes in atherosclerosis progression

Completion of the human genome sequencing project highlighted the richness of the cellular RNA world, and opened the door to the discovery of a plethora of short and long non-coding RNAs (the dark transcriptome) with regulatory or structural potential, which shifted the balance of pathological gene alterations from coding to non-coding RNAs. Thus, disease risk assessment currently has to also evaluate the expression of new RNAs such as small micro RNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), competing endogenous RNAs (ceRNAs), retrogressed elements, 3'UTRs of mRNAs, etc. We are interested in the pathogenic mechanisms of atherosclerosis (ATH) progression in patients suffering Chronic Kidney Disease, and in this review, we will focus in the role of the dark transcriptome (non-coding RNAs) in ATH progression. We will focus in miRNAs and in the formation of regulatory axes or networks with their mRNA targets and with the lncRNAs that function as miRNA sponges or competitive inhibitors of miRNA activity. In this sense, we will pay special attention to retrogressed genomic elements, such as processed pseudogenes and Alu repeated elements, that have been recently seen to also function as miRNA sponges, as well as to the use or miRNA derivatives in gene silencing, anti-ATH therapies. Along the review, we will discuss technical developments associated to research in lncRNAs, from sequencing technologies to databases, repositories and algorithms to predict miRNA targets, as well as new approaches to miRNA function, such as integrative or enrichment analysis and their potential to unveil RNA regulatory networks.