Tanshinone IIA Regulates MAPK/mTOR Signal-Mediated Autophagy to Alleviate Atherosclerosis through the miR-214-3p/ATG16L1 Axis.

Tanshinone IIA (Tan IIA), the core ingredient of Salvia miltiorrhiza, is commonly used for treating cardiovascular diseases. However, its underlying mechanism in regulating autophagy in atherosclerosis (AS) remains unclear. An in vivo model of AS was constructed using Apolipoprotein E-deficient (ApoE-/-) mice fed with a high-fat diet. Histopathologic changes and lipid accumulation were evaluated by hematoxylin and eosin (HE) and Oil red O staining, respectively. The inflammatory cytokine levels were evaluated by Enzyme-linked immunosorbent assay (ELISA). An oxidized low-density lipoprotein (ox-LDL) was used to induce foam cells in RAW264.7 cells. Cholesterol uptake and efflux assay were used to assess changes in intracellular and extracellular cholesterol levels. The expression levels of autophagy-related protein-16-like protein 1 (ATG16L1) and miR-214-3p in the samples and cells derived from mice were assessed by quantitative real-time polymerase chain reaction (qRT-PCR), and the protein levels of the mitogen-activated protein kinase (MAPK)/mammalian target of rapamycin (mTOR) and autophagy-related markers were detected using western blot. The binding site of miR-214-3p on ATG16L1 was determined using a dual-luciferase reporter assay. We observed a decrease in ATG16L1 and increase in miR-214-3p expression level in the AS mice and ox-LDL stimulated RAW264.7 cells. However, the miR-214-3p and ATG16L1 expression could be reversed by Tan IIA. In vivo experiments showed that Tan IIA alleviated AS by reducing lipid accumulation and inflammatory factor levels and promoting autophagy. The in vitro assays demonstrated that Tan IIA regulated lipid levels and autophagy via the miR-214-3p/ATG16L1 axis to inhibit foam cell formation. Additionally, Tan IIA inhibited the MAPK/mTOR pathway by reducing miR-214-3p expression and promoting autophagy. Findings from this study suggested that Tan IIA regulated the MAPK/mTOR signal-mediated autophagy to alleviate AS through the miR-214-3p/ATG16L1 axis.

lncRNA HOTAIRM1 Activated by HOXA4 Drives HUVEC Proliferation Through Direct Interaction with Protein Partner HSPA5.

Despite the substantial progress in deciphering the pathogenesis of atherosclerosis (AS), cardiovascular mortality is still increasing. Therefore, atherosclerotic cardiovascular disease remains a sweeping epidemic that jeopardizes human health. Disentangling the molecular underpinnings of AS is imperative in the molecular cardiology field. Overwhelming evidence has indicated that the recognition of a fascinating class of players, known as long non-coding RNAs (lncRNAs), provides causality for coordinating AS. However, the function and mechanism of HOTAIRM1 are still poorly understood in human umbilical vein endothelial cells (HUVECs) and AS. Herein, we primarily underscored that lncRNA HOTAIRM1 is potentially responsible for AS; as such, it was dramatically up-regulated in HUVECs upon ox-LDL stimulation. Functionally, HOTAIRM1 knockdown attenuated HUVEC proliferation and potentiated apoptosis in the absence and presence of ox-LDL. Furthermore, HOTAIRM1 was preferentially located in the nuclei of HUVECs. Mechanistically, HOXA4 is directly bound to the HOTAIRM1 promoter and activated its transcription. Of note, a positive feedback signaling between HOXA4 and HOTAIRM1 was determined. Intriguingly, the interplay between HOTAIRM1 and HSPA5 occurred in an RNA-binding protein pattern and a transcription-dependent regulatory manner. In addition, HSPA5 overexpression partially antagonized HUVEC proliferation inhibition of HOTAIRM1 depletion. Taken together, our findings delineate a pivotal functional interaction among HOXA4, HOTAIRM1, and HSPA5 as a novel regulatory circuit for modulating HUVEC proliferation. An in-depth investigation of the HOXA4-HOTAIRM1-HSPA5 axis promises to yield significant breakthroughs in identifying the molecular mechanisms governing AS and developing therapeutic avenues for AS.

The Effect of Extracellular Vesicles on Thrombosis.

The risk of cardiovascular events caused by acute thrombosis is high, including acute myocardial infarction, acute stroke, acute pulmonary embolism, and deep vein thrombosis. In this review, we summarize the roles of extracellular vesicles of different cellular origins in various cardiovascular events associated with acute thrombosis, as described in the current literature, to facilitate the future development of a precise therapy for thrombosis caused by such vesicles. We hope that our review will indicate a new horizon in the field of cardiovascular research with regard to the treatment of acute thrombosis, especially targeting thrombosis caused by extracellular vesicles secreted by individual cells. As more emerging technologies are being developed, new diagnostic and therapeutic strategies related to EVs are expected to be identified for related diseases in the future.

Construction of a circRNA-Mediated ceRNA Network Reveals Novel Biomarkers for Aortic Dissection.

Background: Aortic dissection (AD) is a rare and lethal disorder with its genetic basis remains largely unknown. Many studies have confirmed that circRNAs play important roles in various physiological and pathological processes. However, the roles of circRNAs in AD are still unclear and need further investigation. The present study aimed to elucidate the underlying molecular mechanisms of circRNAs regulation in AD based on the circRNA-associated competing endogenous RNA (ceRNA) network. Methods: Expression profiles of circRNAs (GSE97745), miRNAs (GSE92427), and mRNAs (GSE52093) were downloaded from Gene Expression Omnibus (GEO) databases, and the differentially expressed RNAs (DERNAs) were subsequently identified by bioinformatics analysis. CircRNA-miRNA-mRNA ceRNA network, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were used to predict the potential functions of circRNA-associated ceRNA network. RNA was isolated from human arterial blood samples after which qRT-PCR was performed to confirm the DERNAs. Results: We identified 14 (5 up-regulated and 9 down-regulated) differentially expressed circRNAs (DEcircRNAs), 17 (8 up-regulated and 9 down-regulated) differentially expressed miRNAs (DEmiRNAs) and 527 (297 up-regulated and 230 down-regulated) differentially expressed mRNAs (DEmRNAs) (adjusted P-value <0.05 and | log2FC | > 1.0). KEGG pathway analysis indicated that DEmRNAs were related to focal adhesion and extracellular matrix receptor interaction signaling pathways. Simultaneously, the present study constructed a ceRNA network based on 1 circRNAs (hsa_circRNA_082317), 1 miRNAs (hsa-miR-149-3p) and 10 mRNAs (MLEC, ENTPD7, SLC16A3, SLC7A8, TBC1D16, PAQR4, MAPK13, PIK3R2, ITGA5, SERPINA1). qRT-PCR demonstrated that hsa_circRNA_082317 and ITGA5 were significantly up-regulated, and hsa-miR-149-3p was dramatically down-regulated in AD (n = 3). Conclusion: This is the first study to demonstrate the circRNA-associated ceRNA network is altered in AD, implying that circRNAs may play important roles in regulating the onset and progression and thus may serve as potential biomarkers for the diagnosis and treatment of AD.

Lipopolysaccharide induces pyroptosis through regulation of autophagy in cardiomyocytes.

BACKGROUND: Autophagy, a stress response in eukaryotic cells, is closely related to cardiogenic diseases. Pyroptosis, a newly discovered way of programmed cell death, also plays an important role in cardiovascular disease. However, the role and relationship of autophagy and pyroptosis in lipopolysaccharide (LPS)-induced inflammatory response of cardiomyocytes were still unclear. METHODS: Western blot was performed to determine the expression of poly ADP-ribosepolmesera-1 (PARP-1), LC3B, NLRP3 and GSDMD in cardiomyocytes after the treatment of LPS. Transfection of si-LC3B, western blot and immunofluorescence (IF) staining were performed to investigate the role of autophagy in LPS-induced pyroptosis. Co-immunoprecipitation (Co-IP) assays and quantitative real-time PCR (qRT-PCR) were conducted to explore whether PARP-1 binding to LC3B and modulating its expression. Transfections of si-PARP-1, western blot and IF were carried out to confirm the role of PARP-1 in the regulation of LPS-induced pyroptosis by autophagy. RESULTS: LPS induces autophagy and pyroptosis in cardiomyocytes, enhanced the level of autophagy and inhibited the level of pyroptosis in the concentration of 4 µg/mL. We further proved that autophagy inhibits LPS-induced pyroptosis in cardiomyocytes. In addition, PARP-1 binding to LC3B and regulate the expression of LC3B. Finally, we proved that knockdown of PARP-1 rescued the inhibition of autophagy on LPS-induced pyroptosis of cardiomyocytes. CONCLUSIONS: LPS induces pyroptosis through regulation of autophagy via PARP-1 at a specific concentration, above which it causes deposition of autophagy flow to promote pyroptosis. Inhibiting LPS-induced pyroptosis could be a promising therapeutic target in treating cardiovascular diseases.

Irisin Enhances Angiogenesis of Mesenchymal Stem Cells to Promote Cardiac Function in Myocardial Infarction via PI3k/Akt Activation.

BACKGROUND AND OBJECTIVES: With the growing incidence of acute myocardial infarction (MI), angiogenesis is vital for cardiac function post-MI. The role of bone marrow mesenchymal stem cells (BMSCs) in angiogenesis has been previously confirmed. Irisin is considered a potential vector for angiogenesis. The objective of the present study was to investigate the potential role of irisin in the angiogenesis of BMSCs. METHODS AND RESULTS: In vivo, irisin-treated BMSCs (BMSCs＋irisin) were transplanted into an MI mouse model. On day 28 post-MI, blood vessel markers were detected, and cardiac function and infarct areas of mice were evaluated. In vitro, paracrine effects were assessed by examining tube formation in human umbilical vein endothelial cells (HUVECs) co-cultured with the BMSCs＋irisin supernatant. The scratch wound-healing assay was performed to evaluate HUVEC migration. Western blotting was performed to determine PI3k/Akt pathway activation in the BMSCs＋irisin group. Transplantation of BMSCs＋irisin promoted greater angiogenesis, resulting in better cardiac function in the MI mouse model than in controls. In the BMSC＋irisin group, HUVECs demonstrated enhanced tube formation and migration. Activation of the PI3k/Akt pathway was found to be involved in mediating the role of irisin in the angiogenesis of BMSCs. CONCLUSIONS: In cardiovascular diseases such as MI, irisin administration can enhance angiogenesis of BMSCs and promote cardiac function via the PI3k/Akt pathway, optimizing the therapeutic effect based on BMSCs transplantation.