Plasma exosomes from patients with acute myocardial infarction alleviate myocardial injury by inhibiting ferroptosis through miR-26b-5p/SLC7A11 axis.

AIMS: Ferroptosis promotes myocardial injury in acute myocardial infarction (AMI). Increasing evidence suggests the crucial role of exosomes in post-AMI pathophysiological regulation. We aimed to investigate the effects and underlying mechanisms of plasma exosomes derived from patients with AMI in inhibiting ferroptosis after AMI. METHODS: Plasma exosomes were isolated from controls (Con-Exo) and patients with AMI (MI-Exo). These exosomes were incubated with hypoxic cardiomyocytes or intramyocardially injected into the AMI mice. Histopathological changes, cell viability, and cell death were measured to evaluate the myocardial injury. For the ferroptosis evaluation, iron particle deposition, Fe2+, ROS, MDA, GSH, and GPX4 levels were detected. Exosomal miR-26b-5p expression was detected by qRT-PCR, and the targeting relationship between miR-26b-5p and SLC7A11 was confirmed by dual luciferase reporter gene assay. The role of the miR-26b-5p/SLC7A11 axis in the regulation of ferroptosis was validated by rescue experiments in cardiomyocytes. FINDINGS: Hypoxia-treatment induced ferroptosis and injury in H9C2 cells and primary cardiomyocytes. MI-Exo performed better than Con-Exo in inhibiting hypoxia-induced ferroptosis. miR-26b-5p expression was downregulated in MI-Exo, and miR-26b-5p overexpression significantly eliminated the inhibitory effect of MI-Exo on ferroptosis. Mechanistically, knockdown of miR-26b-5p upregulated SLC7A11/GSH/GPX4 expressions by directly targeting SLC7A11. Moreover, SLC7A11 silencing also reversed the inhibitory effect of MI-Exo on hypoxia-induced ferroptosis. In vivo, MI-Exo significantly inhibited ferroptosis, reduced myocardial injury, and improved the cardiac function of AMI mice. SIGNIFICANCE: Our findings revealed a novel mechanism of myocardial protection that downregulation of miR-26b-5p in MI-Exo notably upregulated SLC7A11 expression, thereby inhibiting post-AMI ferroptosis and alleviating myocardial injury.

miR-186-5p Dysregulation in Serum Exosomes from Patients with AMI Aggravates Atherosclerosis via Targeting LOX-1.

Purpose: The formation of macrophage-derived foam cells via the uptake of modified lipoproteins is a pivotal development event in atherosclerosis. It has been reported that clinical and experimental myocardial infarction could accelerate atherosclerosis. Several studies have suggested the critical role of exosomes in cardiovascular diseases. However, the role of exosomes from patients with acute myocardial infarction (AMI) patients in atherogenesis remains unclear. Patients and Methods: Serum exosomes from AMI patients (AMI-Exo) and control individuals (Con-Exo) were isolated and characterized. These exosomes were studied in vitro and in vivo to determine their impact on macrophage foaming and atherogenesis. Results: Our results showed that AMI-Exo promoted foam cell formation in oxidized low-density lipoprotein (ox-LDL)-treated macrophages and progression of atherosclerosis in high-fat/cholesterol diet-fed ApoE-/- mice together with a significantly upregulated levels of lectin-like ox-LDL receptor-1 (LOX-1). The miR-186-5p was found to be downregulated in AMI-Exo and macrophages administered with AMI-Exo. Moreover, serum exosomal miR-186-5p achieved high diagnostic performance for AMI. Luciferase reporter assay indicated that miR-186-5p directly inhibited LOX-1. The endogenous or exogenous miR-186-5p deficiency enhanced lipid accumulation by upregulating LOX-1, whereas miR-186-5p mimics had a reverse effect. Conclusion: In conclusion, the current findings suggest that dysregulated miR-186-5p in AMI-Exo may explain the contribution of acute ischemia events to the advancement of atherosclerosis by enhancing macrophage foaming via its target, LOX-1.

Exploring the Role of Obesity in Dilated Cardiomyopathy Based on Bio-informatics Analysis.

(1) Background: Obesity is a major risk factor for cardiovascular disease (CVD), contributing to increasing global disease burdens. Apart from heart failure, coronary artery disease, and arrhythmia, recent research has found that obesity also elevates the risk of dilated cardiomyopathy (DCM). The main purpose of this study was to investigate the underlying biological role of obesity in increasing the risk of DCM. (2) Methods: The datasets GSE120895, GSE19303, and GSE2508 were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were analyzed using GSE120895 for DCM and GSE2508 for obesity, and the findings were compiled to discover the common genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted for the common genes in RStudio. In addition, CIBERSORT was used to obtain the immune cellular composition from DEGs. The key genes were identified in the set of common genes by the least absolute shrinkage and selection operator (LASSO) algorithm, the prognostic risk models of which were verified by receiver operator characteristic (ROC) curves in GSE19303. Finally, Spearman's correlation was used to explore the connections between key genes and immune cells. (3) Results: GO and KEGG pathway enrichment analyses showed that the main enriched terms of the common genes were transforming growth factor-beta (TGF-ß), fibrillar collagen, NADPH oxidase activity, and multiple hormone-related signaling pathways. Both obesity and DCM had a disordered immune environment, especially obesity. The key genes NOX4, CCDC80, COL1A2, HTRA1, and KLHL29 may be primarily responsible for the changes. Spearman's correlation analysis performed for key genes and immune cells indicated that KLHL29 closely correlated to T cells and M2 macrophages, and HTRA1 very tightly correlated to plasma cells. (4) Conclusions: Bio-informatics analyses performed for DCM and obesity in our study suggested that obesity disturbed the immune micro-environment, promoted oxidative stress, and increased myocardial fibrosis, resulting in ventricular remodeling and an increased risk of DCM. The key genes KLHL29 and HTRA1 may play critical roles in obesity-related DCM.

Human umbilical vein endothelial cells-derived exosomes enhance cardiac function after acute myocardial infarction by activating the PI3K/AKT signaling pathway.

Currently, acute myocardial infarction (AMI) is one of the leading causes of human health issues worldwide. The sudden and continuous occlusion of the coronary artery results in myocardial hypoxic-ischemic necrosis, which is accompanied by inflammatory infiltration and fibrosis, leading to pathological cardiac remodeling. Exosome-based therapy is a promising cell-free approach for repairing the ischemic myocardium. This study aimed to explore the effects and mechanism of human umbilical vein endothelial cells (HUVECs)-derived exosomes on AMI. The results indicated that the localized injection of HUVECs-derived exosomes in the infarcted area could significantly improve cardiac function in AMI mouse models. It could also ameliorate myocardial fibrosis and decrease infarct size after AMI. Additionally, HUVECs-derived exosomes had cardioprotective effects on the H9C2 cells in hypoxic culture conditions, including increased cell viability and decreased lactate dehydrogenase (LDH) release. In both the in-vivo and in-vitro experiments, HUVECs-derived exosomes could effectively inhibit cardiomyocyte apoptosis. The low expression levels of Bcl-2-associated X protein (Bax) and cleaved caspase-3, high expression levels of B-cell lymphoma 2 (Bcl-2), phosphorylated phosphatidylinositol 3-kinase (p-PI3K), and phosphorylated protein kinase B (p-AKT) were detected in AMI mouse models treated with HUVECs-derived exosomes in-vivo. In conclusion, HUVECs-derived exosomes effectively enhanced cardiac function after AMI and inhibited cardiomyocyte apoptosis, which might be regulated through the phosphatidylinositol 3-kinase (PI3K)/ protein kinase B (AKT) signaling pathway.

Identification of Immune Markers in Dilated Cardiomyopathies with Heart Failure by Integrated Weighted Gene Coexpression Network Analysis.

Dilated cardiomyopathy (DCM), a heterogeneous cardiomyopathy, is a major cause of heart failure and heart transplant. Currently, immunotherapy is believed to be an effective treatment method for DCM. However, individual differences are so obvious that the clinical effect is not satisfactory. In order to find immune-related biomarkers of DCM to guide treatment and improve clinical efficacy, we downloaded a GSE120895 dataset from the Gene Expression Omnibus (GEO) database using CIBERSORT and WGCNA algorithms in RStudio and visualizing the protein-protein interaction (PPI) network for key modules by Cytoscape, and finally obtained six hub genes. A GSE17800 dataset was downloaded from the GEO dataset to verify the diagnostic values of hub genes, MYG1, FLOT1, and ATG13, which were excellent. Our study revealed unpublished potential immune mechanisms, biomarkers, and therapeutic targets of DCM.

MicroRNA-130a attenuates cardiac fibrosis after myocardial infarction through TGF-ß/Smad signaling by directly targeting TGF-ß receptor 1.

Cardiac fibrosis is a common pathophysiological change associated with myocardial infarction (MI), and while there is evidence that miR-130a plays an important role in a variety of fibrotic diseases, its role in the cardiac fibrosis during MI is unclear. Our study aimed to assess miR-130a's ability to modulate cardiac fibrosis post-MI and uncover its potential molecular mechanisms. miR-130a was significantly downregulated in infarcted myocardium and hypoxic cardiac fibroblasts (CFs), whereas TGF-ß, α-SMA, collagen 1 (Col-1), and TGF-ß receptor 1 (TGFBR1) were upregulated. We transfected mice with AAV-9 carrying miR-130a and found that miR-130a overexpression statistically improved cardiac function and reduced the area of cardiac fibrosis in mice post-MI. Eukaryotic transcriptome sequencing and dual-luciferase reporter assay results verified that Tgfbr1 was a target gene of miR-130a. miR-130a inhibition heightened Col-1, α-SMA, and TGFBR1 expressions and Smad3 phosphorylation levels in CFs; however, these increments were suppressed by the overexpression of miR-130a. Meanwhile, co-transfection with TGFBR1 weakened miR-130a's ability to inhibit α-SMA and Col-1 expression. These findings suggest that miR-130a exerts antifibrotic properties by directly targeting TGFBR1 to regulate TGF-ß/Smad signaling and inhibit the conversion of CFs to myofibroblasts. Thus, miR-130a is a promising therapeutic target for alleviating cardiac fibrosis.

Corrected QT interval in hospitalized patients with coronavirus disease 2019: Focus on drugs therapy.

ABSTRACT: Corrected QT (QTc) interval prolongation has been associated with poor patient prognosis. In this study, we assessed the effects of different drugs and cardiac injury on QTc interval prolongation in patients with coronavirus disease 2019 (COVID-19).The study cohort consisted of 395 confirmed COVID-19 cases from the Wuhan Union Hospital West Campus. All hospitalized patients were treated with chloroquine/hydroxychloroquine (CQ/HCQ), lopinavir/ritonavir (LPV/r), quinolones, interferon, Arbidol, or Qingfei Paidu decoction (QPD) and received at least 1 electrocardiogram after drug administration.Fifty one (12.9%) patients exhibited QTc prolongation (QTc ≥ 470 ms). QTc interval prolongation was associated with COVID-19 severity and mortality (both P < .001). Administration of CQ/HCQ (odds ratio [OR], 2.759; 95% confidence interval [CI], 1.318-5.775; P = .007), LPV/r (OR, 2.342; 95% CI, 1.152-4.760; P = .019), and quinolones (OR, 2.268; 95% CI, 1.171-4.392; P = .015) increased the risk of QTc prolongation. In contrast, the administration of Arbidol, interferon, or QPD did not increase the risk of QTc prolongation. Notably, patients treated with QPD had a shorter QTc duration than those without QPD treatment (412.10 [384.39-433.77] vs 420.86 [388.19-459.58]; P = .042). The QTc interval was positively correlated with the levels of cardiac biomarkers (creatine kinase-MB fraction [rho = 0.14, P = .016], high-sensitivity troponin I [rho = .22, P < .001], and B-type natriuretic peptide [rho = 0.27, P < .001]).In conclusion, QTc prolongation was associated with COVID-19 severity and mortality. The risk of QTc prolongation was higher in patients receiving CQ/HCQ, LPV/r, and quinolones. QPD had less significant effects on QTc prolongation than other antiviral agents.

Arrhythmias in patients with coronavirus disease 2019 (COVID-19) in Wuhan, China: Incidences and implications.

BACKGROUND: Coronavirus disease 2019 (COVID-19) continues to impact populations around the globe. Information regarding the incidences and implications of arrhythmias in COVID-19 is limited. METHODS: A total of 463 patients with COVID-19 and who had at least one electrocardiogram recording from February 1 to March 19, 2020, in Wuhan Union Hospital were enrolled in the study. RESULTS: Arrhythmias occurred in 85 of 463 (18.4%) patients: atrial arrhythmias in 10.2%, junctional arrhythmias in 0.2%, ventricular arrhythmias in 3.5%, and conduction block in 7.3%. Compared with patients without arrhythmias, those with arrhythmias had higher mortality, both during the time from symptom onset (p < 0.001) and from admission to follow-up (p < 0.001). The frequencies of severe COVID-19 (44.7% vs. 21.2%; p < 0.001) and death (25.9% vs. 10.1%; p < 0.001) were higher in patients with arrhythmias than in those without arrhythmias. Atrial arrhythmias and ventricular arrhythmias could predict severity and mortality, their odds ratios (OR) were 4.45 (95% confidence interval [CI] 2.35 to 8.40), 5.80 (95% CI 1.89 to 17.76) respectively for severity, and were 3.51 (95% CI 1.74 to 7.08), 3.41 (95% CI 1.13 to 10.24) respectively for mortality. High levels of interleukin-6 (IL-6) and IL-10 were associated with the occurrence of arrhythmias (all p < 0.05). CONCLUSION: Arrhythmias were significantly associated with COVID-19 severity and mortality. Atrial arrhythmia was the most frequent arrhythmia type. IL-6 and IL-10 levels can predict the risk of arrhythmias in COVID-19 patients.

Immunotherapy against angiotensin II receptor ameliorated insulin resistance in a leptin receptor-dependent manner.

The angiotensin II type 1 receptor (AT1R) signaling pathway is reported to modulate glucose metabolism. Targeting AT1R, our group invented ATRQß-001 vaccine, a novel immunotherapeutic strategy to block the activation of AT1R. Here, we evaluated the therapeutic efficacy of ATRQß-001 vaccine in insulin resistance, and investigated the mechanism. Our results showed that ATRQß-001 vaccine and specific monoclonal antibody against epitope ATR-001 (McAb-ATR) decreased fasting serum insulin concentration and improved glucose and insulin tolerance in ob/ob mice. These beneficial effects were verified in high-fat diet-induced obese mice. McAb-ATR activated insulin signaling in skeletal muscle and insulin-resistant C2C12 myotubes without affecting liver or white adipose tissue of ob/ob mice. Mechanistically, the favorable impact of McAb-ATR on insulin resistance was abolished in db/db mice and in C2C12 myotubes with leptin receptor knockdown. AT1R knockdown also eradicated the effects of McAb-ATR in C2C12 myotubes. Furthermore, McAb-ATR treatment was able to activate the leptin receptor-mediated JAK2/STAT3 signaling in skeletal muscle of ob/ob mice and C2C12 myotubes. Additionally, angiotensin II downregulated the leptin signaling in skeletal muscle of ob/ob and diet-induced obese mice. We demonstrated that ATRQß-001 vaccine and McAb-ATR improved whole-body insulin resistance and regulated glucose metabolism in skeletal muscle in a leptin receptor-dependent manner. Our data suggest that immunotherapy targeting AT1R is a novel strategy for treating insulin resistance.

ATRQß-001 Vaccine Prevents Experimental Abdominal Aortic Aneurysms.

Background We have developed a peptide vaccine named ATRQß-001, which was proved to retard signal transduction initiated by angiotensin II (Ang II). Ang II was implicated in abdominal aortic aneurysm (AAA) progression, but whether the ATRQß-001 vaccine would prevent AAA is unknown. Methods and Results Ang II-infused ApoE-/- mice and calcium phosphate-induced AAA in C57BL/6 mice were used to verify the efficiency of ATRQß-001 vaccine in AAA. Results demonstrated that the vaccine effectively restrained the aneurysmal dilation and vascular wall destruction of aorta in both animal models, beyond anti-hypertensive effects. In Ang II-induced AAA vascular sections, Immunohistochemical staining showed that the vaccine notably constrained vascular inflammation and vascular smooth muscle cell (VSMC) phenotypic transition, concurrently reduced macrophages infiltration. In cultured VSMC, the anti-ATR-001 antibody inhibited osteopontin secretion induced by Ang II, thereby impeded macrophage migration while co-culture. Furthermore, metalloproteinases and other matrix proteolytic enzymes were also found to be limited by the vaccine in vivo and in vitro. Conclusions ATRQß-001 vaccine prevented AAA initiation and progression in both Ang II and calcium phosphate-induced AAA models. And the beneficial effects were played beyond decrease of blood pressure, which provided a novel and promising method to take precautions against AAA.

Diosmetin inhibits osteoclast formation and differentiation and prevents LPS-induced osteolysis in mice.

Osteolytic bone diseases are closely linked to the over-activation of osteoclasts and enhancement of bone resorption. It has become a major health issue in orthopedic practice worldwide. Inhibition of osteoclasts is proposed to be the main treatment for osteolytic disorders. Diosmetin (DIO) is a natural flavonoid with properties of antioxidant, anti-infection, and antishock. The effect of DIO on osteoclast differentiation is poorly understood. In this study project, we found that DIO could inhibit osteoclastic formation induced by receptor activator of nuclear factor kappa-B ligand (RANKL) in a dose-dependent manner. The expression of the osteoclast differentiation marker genes, cathepsin K, nuclear factor of activated T-cells 1 (NFATc1), Acp5, Ctr, Atp6v0d2, and Mmp9 were also decreased by the treatment of DIO. In addition, DIO attenuated the formation of actin ring and the ability of bone resorption. Further, the western blotting showed that DIO inhibits the phosphorylation of the mitogen-activated protein kinases signaling pathway induced by RANKL, accompanied by the downregulation of NFATc1 and c-Fos expression. We also found that DIO could reduce the accumulation of reactive oxygen species (ROS) induced by RANKL. In vivo, the study revealed that DIO can significantly reduce LPS-induced osteolysis in mice. Collectively, our study shows that DIO can inhibit osteoclast formation and activation, and could serve as a potential therapeutic drug for osteolytic bone diseases.

Mahuang-Xixin-Fuzi decoction reduces the infection of influenza A virus in Kidney-Yang deficiency syndrome mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Mahuang-Xixin-Fuzi Decoction (MXF) as a famous formula for the treatment of colds, fever, nasal congestion and headache with elder people, has always been widely used in traditional Chinese medicine. The present study is aimed at investigating the treatment effect of MXF on Kidney-Yang deficiency syndrome in mice simultaneously infected with H1N1 virus. MATERIALS AND METHODS: We employed the Kidney-Yang deficiency mouse model to investigate the effect of MXF against influenza A virus (A/FM/1/47, H1N1). Mice were infected with the virus after fifteen days Kidney-Yang deficiency syndrome was established (intraperitoneal injection of estradiol benzoate), while MXF was orally administrated with 1.2-4.7g/kg/d for 6 consecutive days after inoculation. Body weight, rectal temperature, morbidity, and mortality were recorded daily. Histopathologic changes, antioxidant activity of SOD and MDA were detected. Moreover, levels of inflammatory cytokines including IL-6, IL-10, MCP-1, TNF-α were measured in the sera of mice. RESULTS: We found that the extract of MXF at dosages of 2.3-4.7g/kg could effectively diminish mortality rate, ameliorate lung edema and inflammation. Administration of MXF decoction significantly depressed the expression of IL-6, MCP-1 and TNF-α, and markedly increased expression of IL-10 in serum. Simultaneously, the extract was also found to reduce MDA and increase SOD in the lung tissue of mice. CONCLUSION: These data support the notion that the extract of MXF could treat Kidney-Yang deficiency syndrome in mice simultaneously infected with influenza A virus by reducing inflammation and increasing antioxidant activities.