Hsa_ circ_0006867 regulates ox-LDL-induced endothelial injury via the miR-499a-3p/ADAM10 axis.

Circular RNAs (circRNAs) have been reported to participate in the development of various diseases. In this study, we investigated the potential mechanism underlying the role of circRNAs in atherosclerosis. Human umbilical vein endothelial cells (HUVECs) were treated with 100µg/mL oxidized low-density lipoprotein (ox-LDL) to simulate atherosclerosis. We observed that hsa_circ_0006867 (circ_0006867), a circRNA markedly increased in ox-LDL-treated endothelial cells, acted as a molecular sponge of miR-499a-3p and regulated its expression. This interaction led to changes in the downstream target gene ADAM10, thus affecting cell apoptosis and migration. Thus, our study suggests that circ_0006867 regulates ox-LDL-induced endothelial injury via the circ_0006867/miR-499a-3p/ADAM10 axis, indicating its potential as an exploitable therapeutic target for atherosclerosis.

Identification of hub genes and their correlation with immune infiltration in coronary artery disease through bioinformatics and machine learning methods.

Background: Coronary artery disease (CAD) is a multifactorial disease and its pathogenesis remains unclear. We aimed to explore the optimal feature genes (OFGs) for CAD and to investigate the function of immune cell infiltration of CAD. It will be helpful for better understanding of the pathogenesis and the development of genetic prediction of CAD. Methods: Datasets related to CAD were obtained from the Gene Expression Omnibus (GEO) database. Cases from the datasets met diagnostic criteria including clinical symptoms, electrocardiographic (ECG) and angiographic evidence. We identified differentially expressed genes (DEGs) and conducted functional enrichment analysis. OFGs were obtained from the least absolute shrinkage and selection operator (LASSO) algorithm, support vector machine recursive feature elimination (SVM-RFE) algorithm, and random forest (RF) algorithm. CIBERSORT was used to compare immune infiltration between CAD patients and normal controls, and the correlation between OFGs and immune cells was analyzed. Results: DEGs were involved in the interleukin (IL)-17 signaling pathway, nuclear factor (NF)-kappa B signaling pathway, and tumor necrosis factor (TNF) signaling pathway. Gene Ontology (GO) analysis revealed DEGs were enriched in lipopolysaccharide (LPS), tertiary granule, and pattern recognition receptor activity. Disease Ontology (DO) analysis suggested DEGs were enriched in lung disease, arteriosclerotic cardiovascular disease (CVD). Matrix metalloproteinase 9 (MMP9), Pellino E3 ubiquitin protein ligase 1 (PELI1), thrombomodulin (THBD), and zinc finger protein 36 (ZFP36) were screened by the intersection of OFGs obtained from LASSO, SVM-REF, and RF algorithms. CAD patients had a lower proportion of memory B cells (P=0.019), CD8 T cells (P<0.001), resting memory CD4 T cells (P<0.001), regulatory T cells (P=0.028), and gamma delta T cells (P<0.001) than normal controls, while the proportion of activated memory CD4 T cells (P=0.014), resting natural killer (NK) cells (P<0.001), monocytes (P<0.001), M0 macrophages (P=0.023), activated mast cells (P<0.001), and neutrophils (P<0.001) in CAD patients were higher than normal controls. MMP9, PELI1, THBD, and ZFP36 were correlated with immune cells. Conclusions: MMP9, PELI1, THBD, and ZFP36 may be predicted biomarkers for CAD. The OFGs and association between OFGs and immune infiltration may provide potential biomarkers for CAD prediction along with the better assessment of the disease.

Effect of Lentivirus-Mediated miR-499a-3p on Human Umbilical Vein Endothelial Cells.

OBJECTIVE: To explore the possible role of miR-499a-3p in the function of primary human umbilical vein endothelial cells (HUVECs) and the expression of ADAM10 in primary HUVEC. METHOD: miR-499a-3p was first transfected into primary HUVECs via lentivirus vector. The viability, proliferation, and migration of stable transfected primary HUVEC were then determined by flow cytometry, CCK8 assays, scratch tests, and Transwell tests. The transcription of miR-499a-3p and ADAM10 was examined by reverse transcription-polymerase chain reaction (RT-PCR), and the expression of ADAM10 was examined by Western blot (WB). RESULTS: After transfection, miR-499a-3p transcription was significantly increased (P < 0.01), compared to the blank and nonspecific control (NC) groups, while both ADAM10 transcription and expression were significantly decreased (P < 0.05). In contrast, in the inhibitors group, miR-499a-3p transcription was significantly reduced (P < 0.05) whereas both ADAM10 transcription and expression were significantly increased (P < 0.05). The viability, proliferation, and migration of primary HUVECs were significantly impaired (P < 0.05) by the transfection of miR-499a-3p but enhanced by miR-499a-3p inhibitors (P < 0.05). CONCLUSIONS: Upregulation of miR-499a-3p transcription will inhibit the expression of ADAM10 in HUVECs; cell migration and proliferation, however, promote apoptosis. And reverse effects were established by downregulation of miR-499a-3p transcription. All these effects may be achieved by regulating the transcription and expression of ADAM10. These results combined suggested that miR-499a-3p may affect the proliferation, migration, and apoptosis of endothelial cells and regulate AS by regulating ADAM10. miR-499a-3p may become a candidate biomarker for the diagnosis of unstable angina pectoris (UA).

Expression Profile and Potential Functions of Circulating Long Noncoding RNAs in Acute Ischemic Stroke in the Southern Chinese Han Population.

Background: Long noncoding RNAs (lncRNAs) have been confirmed to be associated with ischemic stroke (IS); however, their involvement still needs to be extensively explored. Therefore, we aimed to study the expression profile of lncRNAs and the potential roles and mechanisms of lncRNAs in the pathogenesis of acute ischemic stroke (AIS) in the Southern Chinese Han population. Methods: In this study, lncRNA and mRNA expression profiles in AIS were analyzed using high-throughput RNA sequencing (RNA-Seq) and validated using quantitative real-time polymerase chain reaction (qRT-PCR). Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and network analyses were performed to predict the functions and interactions of the aberrantly expressed genes. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic value of lncRNAs in AIS. Results: RNA-Seq analysis showed that 428 lncRNAs and 957 mRNAs were significantly upregulated, while 791 lncRNAs and 4,263 mRNAs were downregulated in patients with AIS when compared with healthy controls. GO enrichment and KEGG pathway analyses of differentially expressed genes showed that the apoptosis, inflammatory, oxidative and calcium signaling pathways were potentially implicated in AIS pathology. The PCR results showed that the selected lncRNA-C14orf64 and lncRNA-AC136007.2 were significantly downregulated in AIS. ROC curve analysis showed that the area under the ROC curve (AUC) values of lncRNA-C14orf64 and lncRNA-AC136007.2 between AIS and healthy controls were 0.74 and 0.94, respectively. Conclusion: This study provides evidence of altered expression of lncRNAs and their potential functions in AIS. Our findings may facilitate pathological mechanistic studies of lncRNAs in AIS and provide potential diagnostic biomarkers and therapeutic targets for AIS.

Progress in the Mechanism and Clinical Application of Cilostazol.

Cilostazol is a unique platelet inhibitor that has been used clinically for more than 20 years. As a phosphodiesterase type III inhibitor, cilostazol is capable of reversible inhibition of platelet aggregation and vasodilation, has antiproliferative effects, and is widely used in the treatment of peripheral arterial disease, cerebrovascular disease, percutaneous coronary intervention, etc. This article briefly reviews the pharmacological mechanisms and clinical application of cilostazol.

Application of Genome-Wide Association Studies in Coronary Artery Disease.

Coronary artery disease (CAD) is a complex disease caused by the combination of environmental and genetic factors. It is one of the leading causes of death and disability in the world. Much research has been focussed on CAD genetic mechanism. In recent years, genome-wide association study (GWAS) has developed rapidly around the world. Medical researchers around the world have successfully discovered a series of CAD genetic susceptibility genes or susceptible loci using medical research strategies, leading CAD research toward a new stage. This paper briefly summarizes the important progress made by GWAS for CAD in the world in recent years, and then analyzes the challenges faced by GWAS at this stage and the development trend of future research, to promote the transformation of genetic research results into clinical practice and provide guidance for further exploration of the genetic mechanism of CAD.

Novel Functional Role of Heat Shock Protein 90 in Mitochondrial Connexin 43-Mediated Hypoxic Postconditioning.

BACKGROUND/AIMS: Previous studies have shown that heat shock protein 90 (HSP90)-mediated mitochondrial import of connexin 43 (Cx43) is critical in preconditioning cardioprotection. The present study was designed to test whether postconditioning has the same effect as preconditioning in promoting Cx43 translocation to mitochondria and whether mitochondrial HSP90 modulates this effect. METHODS: Cellular models of hypoxic postconditioning (HPC) from rat heart-derived H9c2 cells and neonatal rat cardiomyocytes were employed. The effects of HPC on cardiomyocytes apoptosis were examined by flow cytometry and Hoechst 33342 fluorescent staining. Reactive oxidative species (ROS) production was assessed with the peroxide-sensitive fluorescent probe 2',7'-dichlorofluorescin in diacetate (DCFH-DA). The anti- and pro-apoptotic markers Bcl-2 and Bax, HSP90 and Cx43 protein levels were studied by Western blot analysis in total cell homogenate and sarcolemmal and mitochondrial fractions. The effects on HPC of the HSP90 inhibitor geldanamycin (GA), ROS scavengers superoxide dismutase (SOD) and catalase (CAT), and small interfering RNA (siRNA) targeting Cx43 and HSP90 were also investigated. RESULTS: HPC significantly reduced hypoxia/reoxygenation (H/R)-induced cardiomyocyte apoptosis. These beneficial effects were accompanied by an increase in Bcl-2 levels and a decrease in Bax levels in both sarcolemmal and mitochondrial fractions. HPC with siRNA targeting Cx43 or the ROS scavengers SOD plus CAT significantly prevented ROS generation and HPC cardioprotection, but HPC with either SOD or CAT did not. These data strongly supported the involvement of Cx43 in HPC cardioprotection, likely via modulation of the ROS balance which plays a central role in HPC protection. Furthermore, HPC increased total and mitochondrial levels of HSP90 and the mitochondria-to-sarcolemma ratio of Cx43; blocking the function of HSP90 with the HSP90 inhibitor geldanamycin (GA) or siRNA targeting HSP90 prevented the protection of HPC and the HPC-induced association of Cx43, indicating that mitochondrial HSP90 was important for mitochondrial translocation of Cx43 during HPC. CONCLUSION: Mitochondrial HSP90 played a central role in HPC cardioprotection, and its activity was linked to the mitochondrial targeting of Cx43, the activation of which triggered ROS signaling and the subsequent reduction of redox stress. Consequently, its target gene, Bcl-2, was upregulated, and proapoptotic Bax was inhibited in the sarcolemma and mitochondria, ultimately attenuating H/R-induced cardiomyocyte apoptosis. These data reveal a novel mechanism of HPC protection.

Proteomic analysis of mitral valve in Lewis rat with acute rheumatic heart disease.

Rheumatic heart disease (RHD) makes a heavy burden in human lives and economy. The proteomic analysis of acute rheumatic heart disease (ARHD) can provide precious data to study RHD at the early stages, but no one has looked into. So based on our early research we applied the method of continuous GAS stimulation on Lewis rats to duplicate the animal model of ARHD. And the mitral valves of rats in control group (n=10) and ARHD group (n=10) were selected for proteomic analysis of ARHD with the iTRAQ labeling based 2D LC-ESI-MS/MS quantitative technology. We identified 3931 proteins in valve tissue out of which we obtained 395 differentially expressed proteins containing 176 up-regulated proteins and 119 down-regulated proteins. Changes in levels of GAPDH (6.793 times higher than the control group) and CD9 (2.63 times higher than the control group) were confirmed by Western blot or immunohistochemistry. The differentially expressed proteins such as GAPDH, CD9, myosin, collagen and RAC1 may be potential biomarkers for ARHD. Moreover, the mitral valve protein profile shed light on further understanding and investigating ARHD.