Backgroud: The metabolism of epicardial adipose tissue (EAT) is closely related to coronary atherosclerotic heart disease (CAHD), but the specific mechanism is not fully understood. In this study, we investigated the effects of EAT microenvironment on adipose metabolism from the viewpoint of EAT-derived exosomes and epicardial adipose stem cells (EASCs).Methods: EAT samples from CAHD patients and non-CAHD patients were collected to obtain exosomes via tissue culture. MiRNA sequencing was performed to analyze differences in miRNA expression in exosomes between groups. Luciferase reporter assay was then performed to verify the miRNA target gene. EAT was digested by collagenase to obtain EASCs, which were induced to mature adipocytes in vitro. Immunochemical staining and western blotting were performed to detect protein expression levels.Results: The results showed that CAHD patients had higher levels of EASCs in EAT, and no significant difference in the adipogenic differentiation ability of EASCs was observed between CAHD and non-CAHD patients in vitro. This indicates that the EAT microenvironment is a key factor affecting the adipogenic differentiation of EASCs. The EAT-derived exosomes from CAHD patients inhibited adipogenic differentiation of EASCs in vitro. Sequencing analysis showed that miR-3064-5p was highly expressed in EAT-derived exosomes in CAHD patients, and its inhibitor could improve the adipogenic differentiation of EASCs. Luciferase reporter assay results showed that the target gene of miR-3064-5p is neuronatin (Nnat). Nnat remained silent in EASCs and was less expressed in EAT of CAHD patients.Conclusion: Abovementioned results suggest that Nnat is the key to regulating the adipogenic differentiation of EASCs, and miR-3064-5p in EAT-derived exosomes can inhibit the expression of Nnat by targeting its mRNA, thereby affecting the adipogenic differentiation of EASCs.

This study investigated the effects of reynoutrin on the improvement of ischemic heart failure (IHF) and its possible mechanism in rats. The rat heart failure model was established by permanently ligating the left anterior descending coronary artery (LAD) and administering different doses of reynoutrin. Cardiac function, inflammatory factors releasing, oxidative stress, cardiomyocytes apoptosis, and myocardial fibrosis were evaluated. Western blotting was used to determine protein expression levels of S100 calcium-binding protein A1 (S100A1), matrix metallopeptidase 2(MMP2), MMP9, phosphorylated (p-) p65, and transforming growth factor -β1 (TGF-β1) in myocardial tissue of the left ventricle. Results showed that reynoutrin significantly improved cardiac function, suppressed the release of inflammatory factors, reduced oxidative stress, inhibited cardiomyocytes apoptosis, and attenuated myocardial fibrosis in rats with IHF. In rat myocardial tissue, permanent LAD-ligation resulted in a significant down-regulation in S100A1 expression, whereas reynoutrin significantly up-regulated S100A1 protein expression while down-regulating MMP2, MMP9, p-p65, and TGF-β1 expressions. However, when S100A1 was knocked down in myocardial tissue, the above-mentioned positive effects of reynoutrin were significantly reversed. Reynoutrin is a potential natural drug for the treatment of IHF, and its mechanism of action involves the up-regulation of S100A1 expression, thereby inhibiting expressions of MMPs and the transcriptional activity of nuclear factor kappa-B.

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Purpose Low shear stress has been reported to induce atherosclerosis. In the present study,the objective of our study is the comprehensive identification of CX3CR1 / NF-κB signaling pathway involved in low shear stress( LSS) -induced inflammation in HUVECs through protein profiling and cell function experiment.Methods Human umbilical vein endothelial cell was cultured onglass slides and placed in a parallel plate flow chamber. M199 culture medium was used for low laminar shear stress at 4. 14 dyn/cm2, 2 h for the testing group, CX3CR1 sh-RNA and NF-κB inhibitor PDTC are used to block the effects of CX3CR1 and P65. The expression levels of the protein were determined by western blot analysis. Mononuclear cell adhesion assays and scratch assays are used to detect cell adhesion and migration.Results Western blotting analyses revealed that compared with the controls，there is a significant increase in the expression of CX3CR1, nucleusP65,intercellular adhesion molecule-1( ICAM-1), vascular cell adhesion molecule-1 ( VCAM-1) and Interleukin-6( IL-6), while the expression of cytosolic P65 and IκB was significantly reduced in human umbilical vein endothelial cells ( HUVECs) treated with LSS. CX3CR1 Sh－RNA was use to reveal its effect on LSS-in-duced inflammation. Further, specific NF-κB P65 inhibitors( PDTC) were used to reveal the downstream NF-κB P65 exclusively involved in LSS-induced inflammation in HUVECs, this effect can be abrogated by CX3CR1 sh-RNA and NF-κB inhibitors. Monocyte adhesion assay and scratch test revealed LSS promotes adhesion of monocytes and migration of cells, this effect can be abrogated by CX3CR1 sh-RNA and NF-κB inhibitors. LSS is involved in the expression of adhesion molecules and chemokines, which are important for the initiation of endothelial inflammation-related atherosclerosis.Conclusions The activation of CX3CR1 /NF-κB signaling pathway induced by low shear stress in endothelial cells may lead to the future therapeutic targets of atherosclerotic inflammation.

Objective: MiR-6870-3p acts as a crucial regulator of gene expression at the posttranscriptional level and participates in immune responses. However, the roles of miR-6870-3p and its target genes and their underlying mechanisms in the inflammatory responses of epicardial adipose tissues (EATs) are unknown.Methods: MiRNA microarray was used to collect miRNA expression profiles in EATs from five patients with coronary artery disease (CAD) and four individuals without CAD (n-CAD). Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to check the expression of miR-6870-3p in CAD and n-CAD EATs. The mRNA and protein expression levels of Tollip and the key genes of the TLR4 signaling pathway were examined by qRT-PCR and Western blot. The levels of inflammatory factors in the cell supernatant were measured by enzyme-linked immunosorbent assay. Bioinformatics algorithms were used to predict the target gene of miR-6870-3p, and the result was validated by dual-luciferase reporter assay. The protein expression levels of JNK and NF-κB were measured by Western blot.Resules:Our results showed that miR-6870-3p was remarkably higher in CAD EATs than in n-CAD EATs. MiR-6870-3p was positively correlated with TLR4, IL-6, JNK, NF-κB (p65), and TNF-α in CAD EAT samples. Lipopolysaccharide (LPS) treatment upregulated miR-6870-3p mRNA expression and downregulated Tollip mRNA and protein expression in macrophages. MiR-6870-3p upregulation also aggravated the production of proinflammatory cytokines, such as TNF-α and IL-6, when the macrophages were stimulated with LPS. The result of luciferase reporter assays confirmed that miR-6870-3p directly targets Tollip. Moreover, miR-6870-3p upregulation in macrophages resulted in the activation of the JNK/NF-κB pathway.Conclusion:Our study concluded that miR-6870-3p regulates human EAT inflammation by targeting Tollip-mediated JNK and NF-κB signaling events.