Ellagic acid ameliorates monocrotaline-induced pulmonary artery hypertension via exerting its anti-oxidative property inhibiting NLRP3 inflammasome signal pathway in rats.

BackgroundThe atrial fibrillation (AF) associated microRNAs (miRNAs) were found in the right atrium (RA) and left atrium (LA) from patients with rheumatic mitral valve disease (RMVD). However, most studies only focus on the RA; and the potential differences of AF-associated miRNAs between the RA and LA are still unknown. The aim of this study was to perform miRNA expression profiles analysis to compare the potential differences of AF-associated miRNAs in the right atrial appendages (RAA) and left atrial appendages (LAA) from RMVD patients.MethodsSamples tissues from the RAA and LAA were obtained from 18 RMVD patients (10 with AF) during mitral valve replacement surgery. From these tissues, miRNA expression profiles were created and analyzed using a human miRNA microarray. Then, the results were validated using qRT-PCR analysis for 12 selected miRNAs. Finally, potential targets of 10 validated miRNAs were predicted and their functions and potential pathways were analyzed using the miRFocus database.ResultsIn RAA, 65 AF-associated miRNAs were found and significantly dysregulated (i.e. 28 miRNAs were up-regulated and 37 were down-regulated). In LAA, 42 AF-associated miRNAs were found and significantly dysregulated (i.e. 22 miRNAs were up-regulated and 20 were down-regulated). Among these AF-associated miRNAs, 23 of them were found in both RAA and LAA, 45 of them were found only in RAA, and 19 of them were found only in LAA. Finally, 10 AF-associated miRNAs validated by qRT-PCR were similarly distributed in RAA and LAA; 3 were found in both RAA and LAA, 5 were found only in RAA, and 2 were found only in LAA. Potential miRNA targets and molecular pathways were identified.ConclusionsWe have found the different distributions of AF-associated miRNAs in the RAA and LAA from RMVD patients. This may reflect different miRNA mechanisms in AF between the RA and LA. These findings may provide new insights into the underlying mechanisms of AF in RMVD patients.

BackgroundMicroRNAs were enrolled in various cardiovascular disease especially ischemic heart diseases, but the microRNA changes during myocardial ischemia reperfusion injury underwent cardiopulmonary bypass are still unknown. This study screens the microRNA differences in CPB canines and evaluates the relationship of microRNAs with myocardial ischemia reperfusion injury.Methods13 healthy canines received CPB with 60 minutes of aortic clamping and cardioplegic arrest, followed by 90 minutes reperfusion. Left ventricular myocardial samples, blood samples and hemodynamic data were taken at different time points. We performed microRNAs microarray experiments upon the left ventricle myocardium tissue of canines before CPB and after reperfusion for 90 minutes by pooling 3 tissue samples together and used qRT-PCR for confirmation.ResultsStatistically significant difference was found in mir-499 level before CPB and after reperfusion (T1 vs. T4, p = 0.041). We further examined the mir-499 levels by using qRT-PCR in all 13 canines at 4 different time points (T1 vs. T4, p = 0.029). Mir-499 expression was negatively correlated with cardiac troponin T (cTnT) and creatine kinase- MB (CK-MB) levels of canines in all time points samples (r = 0.469, p < 0.001 and r = 0.273, p = 0.050 respectively). Moreover, higher mir-499 expression level was associated with higher dP/dtmax at 25 minutes and 90 minutes after reperfusion.ConclusionMyocardial ischemic reperfusion injury with cardiopulmonary bypass results in declining level of mir-499 expression in left ventricle myocardium of canines, suggesting mir-499 would be a potential therapeutic target in cardiac protection during open heart surgery.

Objective— Myocardial injury during cardiac surgery is a major cause of perioperative morbidity and mortality. We determined whether perioperative statin therapy is cardioprotective in patients undergoing noncoronary artery cardiac surgery and the potential mechanisms. Methods and Results— One hundred fifty-one patients undergoing noncoronary artery cardiac surgery were randomly assigned to either a statin group (n=77) or a control group (n=74). Simvastatin (20 mg) was administered preoperatively and postoperatively. Plasma were analyzed for troponin T, isoenzyme of creatine kinase, C-reaction protein, interleukin-6, interleukin-8, creatinine, and blood urea nitrogen. Cardiac echocardiography was performed. Endothelial nitric oxide synthase (eNOS), Akt, p38, heat shock protein 90, caveolin-1, and nitric oxide (NO) in the heart were detected. Simvastatin significantly reduced plasma troponin T, isoenzyme of creatine kinase, C-reaction protein, blood urea nitrogen , creatinine, interleukin-6, interleukin-8, and the requirement of inotropic postoperatively. Simvastatin increased NO production, the expression of eNOS and phosphorylation at serine1177, phosphorylation of Akt, expression of heat shock protein 90, heat shock protein 90 association with eNOS and decreased eNOS phosphorylation at threonine 495, phosphorylation of p38, and expression of caveolin-1. Simvastatin also improved cardiac function postoperatively. Conclusion— Perioperative statin therapy can improve cardiac function and renal function by reducing myocardial injury and inflammatory response through activating Akt-eNOS and attenuating p38 signaling pathways in patients undergoing noncoronary artery cardiac surgery. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01178710.

BackgroundStructural changes of the left and right atria associated with atrial fibrillation (AF) in mitral stenosis (MS) patients are well known, and alterations in microRNA (miRNA) expression profiles of the right atria have also been investigated. However, miRNA changes in the left atria still require delineation. This study evaluated alterations in miRNA expression profiles of left atrial tissues from MS patients with AF relative to those with normal sinus rhythm (NSR).MethodsSample tissues from left atrial appendages were obtained from 12 MS patients (6 with AF) during mitral valve replacement surgery. From these tissues, miRNA expression profiles were created and analyzed using a human miRNA microarray. Results were validated via reverse-transcription and quantitative PCR for 5 selected miRNAs. Potential miRNA targets were predicted and their functions and potential pathways analyzed via the miRFocus database.ResultsThe expression levels of 22 miRNAs differed between the AF and NSR groups. Relative to NSR patients, in those with AF the expression levels of 45% (10/22) of these miRNAs were significantly higher, while those of the balance (55%, 12/22) were significantly lower. Potential miRNA targets and molecular pathways were identified.ConclusionsAF alters the miRNA expression profiles of the left atria of MS patients. These findings may be useful for the biological understanding of AF in MS patients.