Chongyou Lee

MicroRNA-19b functions as potential anti-thrombotic protector in patients with unstable angina by targeting tissue factor.

The activation of a hemostatic system plays a critical role in the incidence of acute coronary events. Hemostatic proteins may be regulated by microRNAs (miRNAs). Microparticles (MPs) are the major carrier of circulating miRNAs. The aim of this study was to determine the potential role of miRNAs in regulating gene expression involved in the hemostatic system in patients with unstable angina (UA). MiRNA expression profiles in the plasma from patients with UA (UA group, n=9) compared with individuals with clinical suspicion of coronary artery disease (CAD) but negative angiography (control group, n=9) showed that among 36 differentially expressed miRNAs, miR-19b was the most obvious one. Using real-time PCR, 5 selected miRNA levels in plasma (UA group, n=20; control group, n=30) and plasma MPs (UA group n=6; control group n=6) were proved to be consistent with the miRNA array. Flow cytometry analysis indicated that the amounts of plasma endothelial microparticles (EMPs) were increased in UA patients (UA group, n=4) compared to controls (control group, n=4). In cultured endothelial cells (ECs), TNF-α increased miR-19b release and expression. Tissue factor (TF) was predicted to be the target of miR-19b by bioinformatics analysis. Luciferase reporter assays demonstrated that miR-19b binds to TF mRNA. Overexpression of miR-19b inhibited TF expression and procoagulant activity. This study indicates that in UA patients, the increase of miR-19b wrapped in EMPs due to endothelial dysfunction may partially contribute to the circulating miR-19b elevation and miR-19b may play an anti-thrombotic role by inhibiting the expression of TF in ECs.

TRPV1 activation is involved in the cardioprotection of remote limb ischemic postconditioning in ischemia-reperfusion injury rats.

Limb remote ischemic postconditioning (RIPostC) has been proved to be a safe and effective measurement of cardioprotection against ischemia-reperfusion injury. But what bridges the remote organ insult and the cardioprotective effect in heart remains to be elucidated. This study aimed to found that whether TRPV1 may mediate the cardioprotective effect from remote organ to heart and the role of CGRP and SP in this process. We found that RIPostC effectively ameliorated cardiac ischemia/reperfusion injury in terms of limiting infarct size, lowering CK and cTnI release and improving cardiac function. In addition, these cardioprotective effects could be significantly abolished by inhibition of either CGRP or SP receptors with corresponding antagonists (CGRP8-37 for CGRP and RP-67580 for SP) injected before reperfusion. Besides, RIPostC resulted in significantly increase in the levels of CGRP and SP in plasma and hearts, as well as the levels and mRNA expression of CGRP and SP in DRG. The increase in CGRP and SP levels in plasma and hearts were markedly inhibited by TRPV1 receptor antagonist capsazepine. These findings indicate that limb remote ischemic postconditioning could attenuate cardiac ischemia/reperfusion injury in rats, and the cardioprotective mechanism is via TRPV1-mediated upregulation of CGRP and SP, which could subsequently act on their corresponding receptors in heart tissue.

Adverse events following statin-fenofibrate therapy versus statin alone: a meta-analysis of randomized controlled trials.

The combination of fenofibrate with statins is a beneficial therapeutic option for patients with mixed dyslipidaemia, but concerns about adverse events (AEs) make physicians reluctant to use this combination therapy. Medline, Embase and the Cochrane Library were searched to identify 13 randomized controlled trials, involving 7712 patients, of statin–fenofibrate therapy versus statin alone for review. There were significant decreases in low‐density lipoprotein–cholesterol, triglycerides and total cholesterol and increases in high‐density lipoprotein–cholesterol in patients receiving combination therapy compared with statin therapy alone. The incidence of aminotransferase elevations in the fenofibrate–statin therapy group was significantly higher than in the statin monotherapy group (odds ratio (OR), 1.66; 95% confidence interval (CI) 1.17–2.37; P < 0.05). The incidence of elevated creatine kinase levels (OR 0.88; 95% CI 0.63–1.23; P > 0.05), muscle‐associated AEs (OR 0.98; 95% CI 0.88–1.09; P > 0.05) and withdrawals attributed to liver and muscle dysfunction did not differ significantly between the two groups. The efficacy of fenofibrate + standard‐dose statin and incidence of AEs in the fenofibrate + standard‐dose statin group were almost identical to those in the fenofibrate–statin group. In conclusion, combination therapy improves the blood lipid profile of patients. Fenofibrate–statin combination therapy appears to be as well tolerated as statin monotherapy. Physicians should consider fenofibrate–statin combination therapy in patients but monitor aminotransferase levels to avoid hepatic complications.

Effects of statin on circulating microRNAome and predicted function regulatory network in patients with unstable angina

BackgroundStatin therapy plays a pivotal role in stabilizing the plaque for unstable angina (UA) patients although its mechanism(s) remains largely unexplored. Here we aim to identify microRNAs (miRNAs) mediating the protective effect of statins in UA patients.MethodsMiRNAs Array was carried out to compare the circulating whole blood miRNA profile of UA patients treated with (n = 10) and without statin (n = 10) and plasma miRNA profile UA patients treated with (n = 5) and without statin (n = 5). 22 whole blood miRNAs and 19 plasma miRNAs were found significantly upregulated in statin group. Targets of these miRNAs were predicted by algoritms: Targetscan, Miranda and Diana microT, then clustered according to functions and cell types by using the Database for Annotation, Visualization and Integrated Discovery (DAVID). To reveal the enriched function pathways in human atherosclerotic plaque, we analyzed microarray data from GEO database, Coronary atherosclerotic plaque (n = 80); macrophages in ruptured plaque (n = 11); carotid atheroma plaque (n = 64); advanced carotid atherosclerotic plaque (n = 29) using Reactome database. Integrated analysis indicated that statin induced miRNAs mainly regulate the signaling pathways of Rho GTPase and hemostasis in human atherosclerotic lesion. In vulnerable plaque, additional immune system signaling was also targeted.ResultsThe data showed target genes regulated by these statin induced miRNAs majorly expressed in i) plaque macrophage and platelet, where they were involved in hemostasis process; ii) in monocyte to regulate NGF apoptosis; iii) and in endothelial cell function in Rho GTPase pathway. Integrate analysis indicated that statin induced miRNAs mainly regulate the signaling pathways of Rho GTPase and hemostasis in human atherosclerotic lesion.ConclusionsOur study suggest that statin induces the expression of multiple miRNAs in the circulation of UA patient, which play important roles by regulating signal pathways critical for the pathogenesis of UA.

Circulating microRNAs as potential biomarkers for coronary plaque rupture

Coronary plaque rupture is the most common cause of acute coronary syndrome. However, the timely biomarker-based diagnosis of plaque rupture remains a major unmet clinical challenge. Balloon dilatation and stent implantation during percutaneous coronary intervention (PCI) could cause plaque injury and rupture. Here we aimed to assess the possibility of circulating microRNAs (miRNAs) as biomarkers of acute coronary plaque rupture by virtue of the natural model of PCI-induced plaque rupture. Stable coronary artery disease patients underwent PCI with single stent implantation were recruited and a three-phase approach was conducted in the present study: (i) profiling of plasma miRNAs in a group of patients before (0 h) and after balloon dilatation for 1 h (1 h vs. 0 h), (ii) replication of significant miRNAs in the second group of patients (1 h vs. 0 h), (iii) validation of a multi-miRNAs panel in the third group of patients (0.5 h, 1 h vs. 0 h). Out of 24 miRNAs selected for replication, 6 miRNAs remained significantly associated with plaque rupture. In the validation phase, combinations of miR-483-5p and miR-451a showed the highest area under the receiver-operating-characteristic curve (AUC) (0.982; CI: 0.907-0.999) in patients with plaque rupture for 0.5 h; combinations of miR-483-5p and miR-155-5p showed the highest AUC (0.898; CI: 0.790-0.962) after plaque rupture for 1 h. In conclusion, using a profiling-replication-validation model, we identified 3 miRNAs including miR-155-5p, miR-483-5p and miR-451a, which may be biomarkers for the early identification of plaque rupture.

Dietary Capsaicin Improves Glucose Homeostasis and Alters the Gut Microbiota in Obese Diabetic ob/ob Mice

Background: The effects of capsaicin on obesity and glucose homeostasis are still controversial and the mechanisms underlying these effects remain largely unknown. This study aimed to investigate the potential relationship between the regulation of obesity and glucose homeostasis by dietary capsaicin and the alterations of gut microbiota in obese diabetic ob/ob mice. Methods: The ob/ob mice were subjected to a normal, low-capsaicin (0.01%), or high-capsaicin (0.02%) diet for 6 weeks, respectively. Obesity phenotypes, glucose homeostasis, the gut microbiota structure and composition, short-chain fatty acids, gastrointestinal hormones, and pro-inflammatory cytokines were measured. Results: Both the low- and high-capsaicin diets failed to prevent the increase in body weight, adiposity index, and Lees obesity index. However, dietary capsaicin at both the low and high doses significantly inhibited the increase of fasting blood glucose and insulin levels. These inhibitory effects were comparable between the two groups. Similarly, dietary capsaicin resulted in remarkable improvement in glucose and insulin tolerance. In addition, neither the low- nor high-capsaicin diet could alter the α-diversity and β-diversity of the gut microbiota. Taxonomy-based analysis showed that both the low- and high-capsaicin diets, acting in similar ways, significantly increased the Firmicutes/Bacteroidetes ratio at the phylum level as well as increased the Roseburia abundance and decreased the Bacteroides and Parabacteroides abundances at the genus level. Spearmans correlation analysis revealed that the Roseburia abundance was negatively while the Bacteroides and Parabacteroides abundances were positively correlated to the fasting blood glucose level and area under the curve by the oral glucose tolerance test. Finally, the low- and high-capsaicin diets significantly increased the fecal butyrate and plasma total GLP-1 levels, but decreased plasma total ghrelin, TNF-α, IL-1β, and IL-6 levels as compared with the normal diet. Conclusions: The beneficial effects of dietary capsaicin on glucose homeostasis are likely associated with the alterations of specific bacteria at the genus level. These alterations in bacteria induced by dietary capsaicin contribute to improved glucose homeostasis through increasing short-chain fatty acids, regulating gastrointestinal hormones and inhibiting pro-inflammatory cytokines. However, our results should be interpreted cautiously due to the lower caloric intake at the initial stage after capsaicin diet administration.

Adverse events of statin–fenofibric acid versus statin monotherapy: a meta-analysis of randomized controlled trials

Abstract Background: Patients with mixed dyslipidemia can benefit from the combination of fenofibric acid (FA) with statins, but concerns about adverse events make physicians reluctant to prescribe the combination therapy. Objective: In the present study, we performed a meta-analysis of randomized controlled trials (RCTs) to assess the efficacy and adverse events in patients taking statins and FA. Methods: Medline, Embase and the Cochrane Library were searched to identify studies that reported adverse events. Finally, five trials covering 2704 patients were selected in this study. Results: There were significant decreases in TG and increases in HDL-C in patients receiving combination therapy compared with statin monotherapy. The incidence of hepatic toxicity (OR, 3.57; 95% CI, 1.17–10.83; P < 0.05) and increased creatinine (OR, 3.22; 95% CI, 1.28–8.11; P < 0.05) was significantly higher in the FA + low-dose statin group than in the corresponding statin monotherapy. The incidence of CK elevations and muscle-associated AEs was not statistically different between the two groups. The adverse events in the FA + moderate-dose statin group were almost identical to those in the FA + low-dose statin group. Conclusions: In conclusion, combination therapy could improve the blood lipid profile. Addition of FA to statins therapy is more frequently associated with hepatic and renal toxicity than muscle-associated AEs. Therefore patients taking the combination of FA with statins should have liver enzyme and renal function monitored. However, we still need large-scale and long follow-up period RCTs to definitively confirm the adverse events of FA–statin therapy.

Atheroprotective effects of statins in patients with unstable angina by regulating the blood-borne microRNA network

Experimental studies have demonstrated several effects of statins in acute coronary syndrome (ACS) that may extend their clinical benefit beyond the lipid profile modification itself. However, the precise underlying mechanism remains to be elucidated. microRNAs (miRNAs) serve significant roles in the pathophysiology of atherosclerotic plaque progression. The present study investigated the protective role of statins in patients with unstable angina (UA) by regulating the circulating miRNA network. miRNA array results demonstrated that there were 21 differentially expressed miRNAs in non-statin-treated patients with UA (n=8) compared with non-coronary artery disease controls (n=8), and 33 differentially expressed miRNAs in statin-treated patients with UA (n=8) compared with non-statin patients. TargetScan and miRanda programs were used to predict miRNAs target genes. miRNAs target genes in vascular endothelial cells and monocytes were clustered based on the CGAP SAGE library via the Database for Annotation, Visualization and Integrated Discovery (DAVID) platform, and miRNA target genes in platelets were clustered based on a UP tissue-specific library via the DAVID platform. The PANTHER database via DAVID platform was used to perform signaling pathway analysis. The miRNA-gene/pathway network was visualized by Cytoscape software. Bioinformatic analysis suggested that statin-induced miRNAs functions were primarily enriched in angiogenesis, integrin and platelet derived growth factor signaling pathways in UA patients. In endothelial cells and platelets, statin-induced miRNAs primarily targeted the integrin signaling pathway, and in monocytes primarily targeted cytoskeletal regulation by the Rho GTPase signaling pathway. These results revealed that statins may serve systematic protective roles in UA patients by influencing the circulating miRNA regulatory network. Further studies are required to verify the functions of statin-induced miRNAs in endothelial cells, platelets and monocytes.

Plasmatic MicroRNA Signatures in Elderly People with Stable and Unstable Angina

We aimed to investigate the distinctive miRNA profiles in the plasma of elderly patients with unstable angina (UA) and stable angina (SA), and to find more effective markers of UA in elderly people. We compared miRNA expression levels in plasma samples from 10 elderly patients with UA and 10 elderly patients with SA by using microarray-based miRNA chip, and then performed validation with Real-time PCR. Mir-1202, mir-1207-5p, and mir-1225-5p showed a statistically significant down-regulation (P < 0.05), while mir-3162-3p showed an up-regulation (P < 0.05) during validation. Among all single miRNAs, miR-3162-3p showed the highest discriminatory power in the diagnosis of elderly patients with UA (AUC: 0.79, 95% CI: 0.675-0.905). The discriminatory power of a panel of three miRNAs (mir-3162-3p/mir-1225-5p/mir-1207-5p) was highest with an AUC of 0.91 (95% CI: 0.84-0.98), followed by mir-3162-3p/mir-1225-5p (AUC: 0.833, 95% CI: 0.732-0.934) and mir-3162-3p/mir-1207-5p (AUC: 0.817, 95% CI: 0.712-0.922). In conclusion, multi-miRNA panel could provide higher diagnostic value for the diagnosis of elderly patients with UA.

Endothelial microparticles-mediated transfer of microRNA-19b promotes atherosclerosis via activating perivascular adipose tissue inflammation in apoE−/− mice

Microparticles(MPs) are the major carriers of circulating microRNAs. Our previous study has shown that microRNA (miR)-19b in endothelial cell-derived microparticles (EMPs) is significantly increased in patients with unstable angina. However, little is known about the relationship between miR-19b in EMPs and the progression of atherosclerosis. The aim of the present study was to define the role and potential mechanism of miR-19b incorporated in EMPs in the development of atherosclerosis. Western-diet-fed apoE-/- mice were injected with phosphate buffered solution(PBS), EMP carrying microRNA control(EMPcontrol) or miR-19b mimic (EMPmiR19b) intravenously. Systemic treatment with EMPmiR19b significantly accelerated carotid artery atherosclerosis progression by increasing lipid, macrophages and smooth muscle cells and decreasing collagen content in atherosclerotic plaque. Fluorescence-labelled EMPmiR19b injection proved that miR-19b could be transported into perivascular adipose tissue(PVAT) by EMPs. EMPmiR19b treatment also promoted inflammatory cytokines secretion and macrophages infiltration in PVAT. In further experiment, apoE-/- mice were divided into 3 groups: EMPcontrolPVAT(+), EMPmiR19bPVAT(+) and EMPmiR19bPVAT(-), based on removing or keeping pericarotid adipose tissue and injected with EMPcontrol or EMPmiR19b. Loss of PVAT attenuated EMPmiR19b-mediated effects on increasing carotid atherosclerosis formation and inflammatory cytokines level in plaque. EMPmiR19b inhibited suppressor of cytokine signaling 3 (SOCS3) expression in PVAT. Our findings demonstrate that miR-19b in EMPs exaggerates atherosclerosis progression by augmenting PVAT-specific inflammation proceeded by downregulating SOCS3 expression.