Down-regulation of microRNA-342-5p or Up-regulation of Wnt3a Inhibits Angiogenesis and Maintains Atherosclerotic Plaque Stability in Atherosclerosis Mice

Non-coding RNAs and angiogenesis in cardiovascular diseases: a comprehensive review

Non-coding RNAs (ncRNAs) have key roles in the etiology of many illnesses, including heart failure, myocardial infarction, stroke, and in physiological processes like angiogenesis. In transcriptional regulatory circuits that control heart growth, signaling, and stress response, as well as remodeling in cardiac disease, ncRNAs have become important players. Studies on ncRNAs and cardiovascular disease have made great progress recently. Here, we go through the functions of non-coding RNAs (ncRNAs) like circular RNAs (circRNAs), and microRNAs (miRNAs) as well as long non-coding RNAs (lncRNAs) in modulating cardiovascular disorders.

LncRNA/CircRNA-miRNA-mRNA Axis in Atherosclerotic Inflammation: Research Progress

Atherosclerosis is characterized by chronic inflammation of the arterial wall. However, the exact mechanism underlying atherosclerosis-related inflammation has not been fully elucidated. To gain insight into the mechanisms underlying the inflammatory process that leads to atherosclerosis, there is need to identify novel molecular markers. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-protein-coding RNAs (lncRNAs) and circular RNAs (circRNAs) have gained prominence in recent years. LncRNAs/circRNAs act as competing endogenous RNAs (ceRNAs) that bind to miRNAs via microRNA response elements (MREs), thereby inhibiting the silencing of miRNA target mRNAs. Inflammatory mediators and inflammatory signaling pathways are closely regulated by ceRNA regulatory networks in atherosclerosis. In this review, we discuss the role of LncRNA/CircRNA-miRNA-mRNA axis in atherosclerotic inflammation and how it can be targeted for early clinical detection and treatment.

The role of TOP2A in immunotherapy and vasculogenic mimicry in non-small cell lung cancer and its potential mechanism

Type IIA topoisomerase (TOP2A) is significantly associated with malignant tumor development, invasion, treatment and its prognosis, and has been shown to be a therapeutic target against cancer. In contrast, the role of TOP2A in the immunotherapy of non-small cell lung cancer as well as in Vasculogenic mimicry (VM) formation and its potential mechanisms are unclear. The aim of this study was to investigate the role of TOP2A in proliferation, skeleton regulation, motility and VM production in non-small cell lung cancer and its mechanisms by using bioinformatics tools and molecular biology experiments. Subgroup analysis showed that the low-risk group had a better prognosis, while the high-risk group was positively correlated with high tumor mutational load, M1-type macrophage infiltration, immune checkpoint molecule expression, and immunotherapy efficacy. As confirmed by further clinical specimens, the presence of TOP2A and VM was significantly and positively correlated with poor prognosis. Our study established a model based on significant co-expression of TOP2A genes, which significantly correlated with mutational load and immunotherapy outcomes in patients with non-small cell lung cancer. Further mechanistic exploration suggests that TOP2A plays an important role in immunotherapy and VM formation in NSCLC through upregulation of Wnt3a and PD-L1 expression.

LncRNA PEG11as aggravates cerebral ischemia/reperfusion injury after ischemic stroke through miR-342-5p/PFN1 axis

AIM

LncRNAs are highly expressed in the CNS and regulate pathophysiological processes. However, the potential role of lncRNAs inischemic stroke (IS) remains unknown. In this study, we investigated the functions and possible molecular mechanism of lncRNA paternal expressed gene 11 antisense (PEG11as) in this process.

METHODS

Middle cerebral artery occlusion/reperfusion (MCAO/R) mice model and N2a cells model from oxygen-glucose deprivation/reoxygenation (OGD/R) were used to simulate cerebral I/R in vivo and in vitro. High-throughput sequencing (RNA-Seq) was used todetect differential expression of lncRNAs in cerebral I/R. QRT-PCR was used to detect the expression of PEG11as and miR-342-5p. Bioinformatics analysis, FISH, luciferase reporter assay, RIP, Western blot, and immunofluorescence were used to detect the interaction between PEG11as, miR-342-5p and PFN1. The effect on neuronal apoptosis was analyzed using loss-of-function combined with TUNEL, Hoechst, and caspase3 activity assays.

KEY FINDINGS

254 lncRNAs were differentially expressed in MCAO1h/R6h mice. Among them, PEG11as was significantly up-regulated. PEG11as down-regulated could markedly attenuate the brain infarct volume, alleviate neurological deficit in vivo, and effectively promote neuron survival, attenuate neuronal apoptosis both in vivo and in vitro. FISH assay discovered that PEG11as was mainly located in the cytoplasm. Furthermore, we demonstrated that PEG11as was able to bind miR-342-5p to inhibit miR-342-5p activity, whereas the down-regulated of miR-342-5p resulted in profilin 1 (PFN1) overexpression and thus promoting apoptosis.

SIGNIFICANCE

This study suggests that PEG11as regulates neuronal apoptosis by miR-342-5p/PFN1 axis, which may contribute to our understanding of pathogenesis and provide a potential therapeutic option for cerebral I/R.

cGAS-STING Pathway Performance in the Vulnerable Atherosclerotic Plaque

The important role of Ca2+ in pathogenic store-operated calcium entry (SOCE) is well-established. Among the proteins involved in the calcium signaling pathway, Stromal interacting molecule 1 (STIM1) is a critical endoplasmic reticulum transmembrane protein. STIM1 is activated by the depletion of calcium stores and then binds to another calcium protein, Orai1, to form a channel through which the extracellular Ca2+ can enter the cytoplasm to replenish the calcium store. Multiple studies have shown that increased STIM1 facilitates the aberrant proliferation and apoptosis of vascular smooth cells (VSMC) and macrophages which can promote the formation of rupture-prone plaque. Together with regulating the cytosolic Ca2+ concentration, STIM1 also activates STING through altered intracellular Ca2+ concentration, a critical pro-inflammatory molecule. The cGAS-STING pathway is linked with cellular proliferation and phenotypic conversion of VSMC and enhances the progression of atherosclerosis plaque. In summary, we conclude that STIM1/cGAS-STING is involved in the progression of AS and plaque vulnerability.

miRNA in Ischemic Heart Disease and Its Potential as Biomarkers: A Comprehensive Review

Ischemic heart disease (IHD) constitutes the leading global cause of mortality and morbidity. Although significant progress has been achieved in the diagnosis, treatment, and prognosis of IHD, more robust diagnostic biomarkers and therapeutic interventions are still needed to circumvent the increasing incidence of IHD. MicroRNAs (miRNAs) are critical regulators of cardiovascular function and are involved in various facets of cardiovascular biology. While the knowledge of the role of miRNAs in IHD as diagnostic biomarkers has improved, research emphasis on how miRNAs can be effectively used for diagnosis and prognosis of IHD is crucial. This review provides an overview of the biology, therapeutic and diagnostic potential, as well as the caveats of using miRNAs in IHD based on existing research.

The mir-21 Inhibition Enhanced HUVEC Cellular Viability during Hypoxia-Reoxygenation Injury by Regulating PDCD4

The purpose of this study was to explore the clinical value of altered plasma mir-21 expression level as a biomarker for the severity of coronary artery disease (CAD) and its molecular impact on HUVEC cellular injuries. Angiographically validated 56 patients with single-vessel CAD disease, 92 patients with double-vessel CAD, 139 complex coronary artery stenosis patients, and 56 healthy individuals ( $n=343$ ) were enrolled in this study. The expressions of plasma mir-21 were evidently and progressively higher while PDCD4 levels were significantly and steadily lower in single-, dual-, and multivessel occluded CAD patients than in healthy participants ( $P<0.001$ ). The relative expressions of mir-21 in hypoxia-reoxygenation- (HR-) exposed HUVECs were markedly upregulated, but PDCD4 concentrations were obviously downregulated as compared with normal control cells ( $P<0.001$ ). Moreover, altered circulatory mir-21 expression levels were able to significantly differentiate single- (AUC 0.893), double- (AUC 0.914), and multivessel stenosis CAD (AUC 0.933) patients from healthy subjects. Besides, the plasma mir-21 expressions in elderly (66-85 years) groups were remarkably higher than those in younger aged (25-45 years) subjects. Caspase-3 and ROS expression levels were remarkably elevated, but cellular viability noticeably declined in HR-induced HUVECs than in normoxic cells ( $P<0.001$ ). In contrast, mir-21 inhibition markedly reduced caspase-3 activity and ROS concentrations while significantly ameliorating HUVEC cellular viability in HR conditions. PDCD4 expressions in HR-exposed HUVECs were prominently decreased whereas mir-21 inhibition significantly enhanced PDCD4 levels ( $P<0.001$ ). Upregulated plasma mir-21 can be a valuable clinical biomarker for the detection of the severity of coronary artery stenosis patients. Elevated circulatory mir-21 concentrations have a positive correlation with aging. Inhibitory mir-21 evidently increased HUVEC cellular viability through upregulation of targeting PDCD4 and recommended a newer possible therapeutic molecule for the management of CAD patients.

Silencing METTL3 Stabilizes Atherosclerotic Plaques by Regulating the Phenotypic Transformation of Vascular Smooth Muscle Cells via the miR-375-3p/PDK1 Axis

PURPOSE

Atherosclerosis (AS) is a primary cause of cardiovascular diseases. This study investigated the mechanism of methyltransferase-like 3 (METTL3) in AS plaques via modulating the phenotypic transformation of vascular smooth muscle cells (VSMCs).

METHODS

AS mouse models and MOVAS cell models were established through high-fat diet and the treatment of ox-LDL, respectively. METTL3 expression in AS models was detected via RT-qPCR and Western blot. The AS plaques, lipid deposition, and collagen fibers were examined via histological staining. The levels of Ly-6c, α-SMA, and OPN were examined via Western blot. The blood lipid indexes in mouse aortic tissues were determined using kits. The proliferation and migration of MOVAS cells were detected via CCK-8 and Transwell assays. The m⁶A modification level of mRNA was quantified. The binding relationship between pri-miR-375 and DGCR8, and the enrichment of m⁶A on pri-miR-375 were detected via RIP. The binding relationship between miR-375-3p and 3-phosphoinositide-dependent protein kinase-1 (PDK1) was verified via dual-luciferase assay. Joint experiments were designed to investigate the role of miR-375-3P/PDK1 in the phenotypic transformation of VSMCs.

RESULTS

METTL3 was highly expressed in AS. Silencing METTL3 alleviated AS progression and stabilized AS plaques in mice, and limited the phenotypic transformation of VSMCs induced by ox-LDL. Silencing METTL3 inhibited m⁶A level and decreased the binding of DGCR8 to pri-miR-375 and further limited miR-375-3p expression. miR-375-3p targeted PDK1 transcription. miR-375-3p upregulation or PDK1 downregulation facilitated the phenotypic transformation of VSMCs.

CONCLUSION

METTL3-mediated m⁶A modification promoted VSMC phenotype transformation and made AS plaques more vulnerable via the miR-375-3p/PDK1 axis.

Inflammation and atherosclerosis: signaling pathways and therapeutic intervention

Atherosclerosis is a chronic inflammatory vascular disease driven by traditional and nontraditional risk factors. Genome-wide association combined with clonal lineage tracing and clinical trials have demonstrated that innate and adaptive immune responses can promote or quell atherosclerosis. Several signaling pathways, that are associated with the inflammatory response, have been implicated within atherosclerosis such as NLRP3 inflammasome, toll-like receptors, proprotein convertase subtilisin/kexin type 9, Notch and Wnt signaling pathways, which are of importance for atherosclerosis development and regression. Targeting inflammatory pathways, especially the NLRP3 inflammasome pathway and its regulated inflammatory cytokine interleukin-1β, could represent an attractive new route for the treatment of atherosclerotic diseases. Herein, we summarize the knowledge on cellular participants and key inflammatory signaling pathways in atherosclerosis, and discuss the preclinical studies targeting these key pathways for atherosclerosis, the clinical trials that are going to target some of these processes, and the effects of quelling inflammation and atherosclerosis in the clinic.