MiR-31 Downregulation Protects Against Cardiac Ischemia/Reperfusion Injury by Targeting Protein Kinase C Epsilon (PKCe) Directly

Objective: This study aimed to evaluate the protective effects of atorvastatin against myocardial ischemia/reperfusion (I/R) injury in cardiomyocytes and its possible underlying mechanism. Method: Direct cytotoxic effect of OGD/R on cardiomyocytes with and without atorvastatin pretreatment was evaluated. Effects of atorvastatin on expression of GSK-3β and miR-199a-5p were determined using RT-PCR and Western blot. In addition, GSK-3β expression with miR-199a-5p upregulation and downregulation was detected using RT-PCR, Western blot, and immunohistochemistry. Results: Pretreatment with atorvastatin significantly improved the recovery of cells viability from OGD/R (p<0.05). In addition, the atorvastatin pretreatment significantly increased GSK-3β expression both in mRNA level and protein level and decreased miR-199a-5p expression in mRNA level (p<0.05). Upregulation and downregulation of miR-199a-5p respectively decreased and increased GSK-3β expression both in mRNA level and protein level. Conclusion: These results suggested that atorvastatin provides the cardioprotective effects against I/R injury via increasing GSK-3β through inhibition of miR-199a-5p.

Section: Discussionmentioning

confidence: 99%

Atorvastatin Protects Myocardium Against Ischemia-Reperfusion Injury Through Inhibiting miR-199a-5p

Zuo¹,

Wang²,

Hu³

et al. 2016

“…The myocardial infarct size was measured as previously described [14]. Immediately following reperfusion, the LAD was ligated completely and 4 mL of 1% Evans blue dye was injected retrogradely into the aorta to delineate the region of myocardial perfusion.…”

Section: The Determination Of the Infarct Sizementioning

confidence: 99%

The Antioxidant, Anti-Inflammatory and Anti-Apoptotic Activities of the Bauhinia Championii Flavone are Connected with Protection Against Myocardial Ischemia/Reperfusion Injury

Jian

Xuan

et al. 2016

Background/Aims: Previous studies have demonstrated that Bauhinia championii flavone (BCF) exhibits anti-oxidative, anti-hypoxic and anti-stress properties. This study was designed to investigate whether BCF has a cardioprotective effect against myocardial ischemia/reperfusion (I/R) injuries in rats and to shed light on its possible mechanism. Methods: The model of I/R was established by ligating the left anterior descending coronary artery for 30 min, then reperfusing for 180 min. Hemodynamic changes were continuously monitored. The content of malondialdehyde (MDA) as well as the lactate dehydrogenase (LDH), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were assessed. The release of interleukin-6 (IL-6) was measured by enzyme-linked immunosorbent assay (ELISA). Apoptosis of cardiomyocytes was determined by caspase-3 activity and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The expression of TLR4, NF-κBp65, Bcl-2 and Bax were detected by western blotting. Results: Pretreatment with BCF significantly reduced the serum levels of LDH, MDA and IL-6, but increased the activities of SOD and GSH-Px. It also attenuated myocardial infarct size, reduced the apoptosis rate and preserved cardiac function. Furthermore, BCF inhibited caspase-3 activity and the expression of TLR4, phosphorylated NF-κBp65 and Bax, but enhanced the expression of Bcl-2. Conclusion: These results provide substantial evidence that BCF exerts a protective effect on myocardial I/R injury, which may be attributed to attenuating lipid peroxidation, the inflammatory response and apoptosis.

“…Moreover, an accumulating number of miRNAs have been verified to be critically involved in maintaining normal heart function and pathological process involved in cardiovascular diseases [11][12][13][14][15][16][17]. In addition to being potent regulators of gene expression, recent studies have shown that miRNAs may also serve as circulating biomarkers for various diseases, including tumors and cardiovascular disorders, because of their remarkable stability in the blood, urine and other fluids [18][19][20][21].…”

Section: Introductionmentioning

confidence: 99%

Circulating MiR-19b-3p, MiR-134-5p and MiR-186-5p are Promising Novel Biomarkers for Early Diagnosis of Acute Myocardial Infarction

Wang¹,

Zhao²,

Liu³

et al. 2016

118

103

Background/Aims: Recent studies have shown that circulating microRNAs (miRNAs) are emerging as promising biomarkers for cardiovascular diseases. This study aimed to determine whether miR-19b-3p, miR-134-5p and miR-186-5p can be used as novel indicators for acute myocardial infarction (AMI). Methods: To investigate the kinetic expression of the three selected miRNAs, we enrolled 18 patients with AMI and 20 matched controls. Plasma samples were collected from each participant, and total RNA was extracted. Quantitative real-time PCR and ELISA assays were used to investigate the expression of circulating miRNAs and cardiac troponin I (cTnI), respectively. Plasma samples from another age- and gender-matched cohort were collected to investigate the impact of medications for AMI on the expression of the selected miRNAs. Results: Levels of plasma miR-19b-3p, miR-134-5p and miR-186-5p were significantly increased in early stage of AMI. Plasma miR-19b-3p and miR-134-5p levels reached peak expression immediately after admission (T0), whereas miR-186-5p achieved peak expression at 4 h after T0. All of these times were earlier than the peak for cTnI (8 h after T0). In addition, all three miRNAs were positively correlated with cTnI. Receiver Operating Characteristic (ROC) analysis indicated that each single miRNA showed considerable diagnostic efficiency for predicting AMI. Furthermore, combining all three miRNAs in a panel increased the efficiency of distinguishing between patients with AMI and controls. Moreover, we found that heparin and medications for AMI did not impact the expression of these circulating miRNAs. Conclusion: Circulating miR-19b-3p, miR-134-5p and miR-186-5p could be considered promising novel diagnostic biomarkers for the early phase of AMI.