Fas-FasL expression and myocardial cell apoptosis in patients with viral myocarditis

MicroRNAs in Inflammatory Heart Diseases and Sepsis-Induced Cardiac Dysfunction: A Potential Scope for the Future?

Background: MicroRNAs (miRNAs) are small, single-stranded RNA sequences that regulate gene expression on a post-transcriptional level. In the last few decades, various trials have investigated the diagnostic and therapeutic potential of miRNAs in several disease entities. Here, we provide a review of the available evidence on miRNAs in inflammatory heart diseases (myocarditis, endocarditis, and pericarditis) and sepsis-induced cardiac dysfunction. Methods: Systematic database research using the PubMed and Medline databases was conducted between July and September 2019 using predefined search terms. The whole review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: In total, 131 studies were screened, 96 abstracts were read, and 69 studies were included in the review. Discussion: In the future, circulating miRNAs could serve as biomarkers for diagnosis and disease monitoring in the context of inflammatory heart diseases and sepsis-induced cardiac dysfunction. Considering the promising results of different animal models, certain miRNAs could also emerge as novel therapeutic approaches in this setting.

Astragaloside IV reduces cardiomyocyte apoptosis in a murine model of coxsackievirus B3-induced viral myocarditis

Apoptosis plays a crucial role in regulating cardiomyopathy and injuries of coxsackievirus B3 (CVB3)-induced viral myocarditis (VM). It has been reported that Astragaloside IV (AST-IV) from Astragalus membranaceus could inhibit apoptosis under a variety of pathological conditions in vivo or in vitro. However, the functional roles of AST-IV in CVB3-induced VM still remain unknown. Here, we found that AST-IV significantly enhanced survival for CVB3-induced mice. AST-IV protected the mice against CVB3-induced virus myocarditis characterized by the increased body weight, decreased serum level of creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH), supressed expression of Ifn-γ, Il-6 in heart, enhanced systolic and diastolic function of left ventricle. At the pathological level, AST-IV ameliorated the mice against CVB3-induced myocardial damage and myocardial fibrosis. In vitro, the results from flow cytometry showed that AST-IV significantly suppressed CVB3-induced cardiomyocytes apoptosis, which also were verified in vivo. Moreover, an increased expression of pro-apoptotic genes including FAS, FASL, cleaved caspase-8 and cleaved caspase-3 was found in CVB3-induced cardiomyocytes, while those was inhibited in cardiomyocytes treated with AST-IV. Taken together, the data suggest that AST-IV protected against CVB3-induced myocardial damage and fibrosis, which may partly attribute to supress activation of FAS/FASL signaling pathway.

Possible involvement of Fas/FasL-dependent apoptotic pathway in α-bisabolol induced cardiotoxicity in zebrafish embryos

α-Bisabolol, an unsaturated monocyclic sesquiterpene alcohol, is a common ingredient in many pharmaceuticals and personal care products (PPCPs). Despite being widely used, little is known about its toxic effects on organisms and aquatic environment. In this study, we investigated the developmental toxicity of α-Bisabolol, especially its effects on the cardiac development using zebrafish embryos as a model. Embryos at 4 h post-fertilization (hpf) were exposed to 10, 30, 50, 70, 90, and 100 μM α-Bisabolol until 144 hpf. α-Bisabolol caused phenotypic defects and the most striking one is the heart malformation. Treatment of α-Bisabolol significantly increased the cardiac malformation rate, the SV-BA distance, as well as the pericardial edema area, and reduced heart rate in a concentration-dependent manner. Notably, considerable numbers of apoptotic cells were mainly observed in the heart region of zebrafish treated with α-Bisabolol. Further study on α-Bisabolol induced apoptosis in the zebrafsh heart suggested that an activation of Fas/FasL-dependent apoptotic pathway. Taken together, our study investigated the cardiotoxicity of α-Bisabolol on zebrafish embryonic development and its underlying molecular mechanism, shedding light on the full understanding of α-Bisabolol toxicity on living organisms and its environmental impact.

The Optimal Intervention Time of Bone Marrow Mesenchymal Stem Cells in Ameliorating Cardiac Fibrosis Induced by Viral Myocarditis: A Randomized Controlled Trial in Mice

Bone marrow-derived mesenchymal stem cells (BMSCs) have recently been introduced to treat cardiovascular diseases, such as myocardial infarction and dilated cardiomyopathy. Nevertheless, there are few researches focused on the application of BMSCs in treating viral myocarditis, not to mention its optimal intervention timer potential mechanisms. In our study, we concentrated on finding an optimal time window to perform BMSCs treatment in a murine model of myocarditis induced by coxsackievirus B3 (CVB3). On the 1st day, 3rd day, 7th day, and 14th day after BALB/c mice were infected by CVB3, we intravenously injected equivalent BMSCs into the treatment groups. With a 28-day follow-up after inoculation, we found that the ventricular function was significantly improved in the BMSCs treatment group and cardiac fibrosis markedly ameliorated, especially when BMSCs were injected between 1 and 2 weeks after CVB3 inoculation. Furthermore, we demonstrated that after BMSCs treatment, the expressions of TGF-β, col1α1, and col3α1 were significantly decreased. Therefore, we conclude that BMSCs may have a potential to improve CVB3-induced myocarditis by ameliorating cardiac fibrosis through the inhibition of TGF-β expression.