Overview of cardiac markers in heart disease

Dexmedetomidine attenuates myocardial ischemia-reperfusion injury in hyperlipidemic rats by inhibiting inflammation, oxidative stress and NF-κB

The present study was conducted to determine the protective effect of Dexmedetomidine (DEX) in myocardial ischemia-reperfusion injury in hyperlipidemic rats. Towards this, the effect of DEX was first evaluated on the infarct size and the histopathology of cardiac tissues using TTC and H and E staining, and it was found that DEX significantly improved the infarct size and architecture of the myocardial tissues following the I/R injury. DEX also showed significant improvement in various examined hemodynamic parameters (e.g., LVSP, and ± dp/dtmax ) in a dose-dependent manner. The lipid profile (LDL, VLDL, TC, TG, and HDL level) of the rats were also found significantly improved in DEX-treated rats. The level of various pro-inflammatory cytokines (IL-1β, IL-6, IL-10, IL-17, and TNF-α), cardiac injury (CK, CK-MB, Troponin I AST, ALT, and LDH), and oxidative stress (MDA, SOD, and GSH) biomarkers were also found to be restored near to the normal in DEX-treated group. It has been found that DEX also significantly reduces apoptosis of rat cardiomyocytes. In western blot analysis, DEX showed a significant reduction in the activation of NF-κB. In conclusion, our study demonstrated the protective effect of Dexmedetomidine in myocardial ischemia-reperfusion injury in hyperlipidemic rats possibly via amelioration of oxidative stress, and inflammation apoptosis.

Postmortem biochemistry in deaths from ischemic heart disease

Ischemic heart disease (IHD) is one of the leading causes of morbidity and sudden cardiac death worldwide and is an important public health problem. The presence of ischemia in clinical applications can be detected by ECG, biochemical markers, and radiological methods. Myocardial infarction is also frequently encountered in forensic autopsies. Postmortem diagnosis is determined as a result of histopathological examinations and additional exclusionary examinations (toxicology, microbiology, etc.). However, routine histopathological examinations are insufficient, especially when death occurs in the early period of ischemia. It creates a problem for forensic pathologists and forensic medicine specialists in such cases of sudden cardiac death. Postmortem biochemistry is one of the important and promising disciplines in which forensic applications work in order to diagnose these cases correctly. The issue of whether biomarkers used in the diagnosis of myocardial infarction in clinical studies can be used reliably in postmortem cases has been discussed by forensic medicine researchers for some time. This manuscript aims to review and summarize biomarkers belonging to various categories that have been studied in IHD-related deaths, in biological fluids taken at autopsy, or in animal experiments. Our study shows that the postmortem use of biochemical markers in the diagnosis of IHD yields promising results. However, it should not be forgotten that postmortem biochemistry is different from clinical applications due to its dynamics and that the body causes unpredictable changes in markers in the postmortem process. Therefore, comprehensive studies are needed to evaluate the postmortem stability of these markers in different biological fluids, their significance among various causes of death, and whether they are affected by any variable (Cardiopulmonary resuscitation, Postmortem interval, medications, etc.) before they are routinely applied. It is suggested by the authors that the cut-off values of biomarkers whose significance has been proven by these studies should be determined and that they should be used in this way in routine applications.

miRNAs as biomarkers for diagnosis of heart failure: A systematic review and meta-analysis

BACKGROUND

With the rapid development of molecular biology, the kind of mircoRNA (miRNA) has been introduced into emerging role both in cardiac development and pathological procedure. Thus, we conduct this meta-analysis to find out the role of circulating miRNA as a biomarker in detecting heart failure.

METHODS

We searched PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and World Health Organization clinical trials registry center to identify relevant studies up to August 2016. We performed meta-analysis in a fixed/random-effect model using Meta-disc 1.4. We used STATA 14.0 to estimate the publication bias and meta-regression. Besides, we took use of SPSS 17.0 to evaluate variance between several groups. Information on true positive, false positive, false negative, and true negative, as well as the quality of research was extracted.

RESULTS

We use results from 10 articles to analyze the pooled accuracy. The overall performance of total mixed miRNAs (TmiRs) detection was: pooled sensitivity, 0.74 (95% confidence interval [CI], 0.72 to 0.75); pooled specificity, 0.69 (95%CI, 0.67 to 0.71); and area under the summary receiver operating characteristic curves value (SROC), 0.7991. The miRNA-423-5p (miR-423-5p) detection was: pooled sensitivity, 0.81 (95%CI, 0.76 to 0.85); pooled specificity, 0.67 (95%CI, 0.61 to 0.73); and SROC, 0.8600. However, taken the same patients population, we extracted the data of BNP for detecting heart failure and performed meta-analysis with acceptable SROC as 0.9291. Among the variance analysis, the diagnostic performance of miR-423-5p claimed significant advantages of other pooled results. However, the combination of miRNAs and BNP could increase the accuracy of detecting of heart failure. Unfortunately, there was no dramatic advantage of miR-423-5p compared to BNP protocol.

CONCLUSION

Despite interstudy variability, the performance test of miRNA for detecting heart failure revealed that miR-423-5p demonstrated the potential to be a biomarker. However, other miRNAs were not able to provide enough evidence on promising diagnostic value for heart failure based on the current data. Moreover, the combination of miRNAs and BNP could work as a better method to detection. Unfortunately, BNP was still the most convinced biomarker for such disease.

Optimized Collection Protocol for Plasma MicroRNA Measurement in Patients with Cardiovascular Disease

Background. Various microRNAs (miRNAs) are used as markers of acute coronary syndrome, in which heparinization is considered mandatory therapy. Nevertheless, a standard method of handling plasma samples has not been proposed, and the effects of heparin treatment on miRNA detection are rarely discussed. Materials and Method. This study used quantitative polymerase chain reaction (qPCR) analysis to investigate how storage temperature, standby time, hemolysis, and heparin treatment affect miRNA measurement in plasma samples from 25 patients undergoing cardiac catheterization. Results. For most miRNAs, the qPCR results remained consistent during the first 2 hours. The miRNA signals did not significantly differ between samples stored at 4°C before processing and samples stored at room temperature (RT) before processing. miR-451a/miR-23a ratio < 60 indicated < 0.12% hemolysis with 100% sensitivity and 100% specificity. Pretreatment with 0.25 U heparinase I recovered qPCR signals that were reduced by in vivo heparinization. Conclusions. For miRNA measurement, blood samples stored at RT should be processed into plasma within 2 hours after withdrawal and should be pretreated with 0.25 U heparinase I to overcome heparin-attenuated miRNA signals. The miR-451a/miR-23a ratio is a reliable indicator of significant hemolysis.

Time-dependent cellular response in the liver and heart in a dietary-induced obese mouse model: the potential role of ER stress and autophagy

PURPOSE

Both endoplasmic reticulum stress (ER stress) and autophagy are essential for the response of the protein quality control system to cellular stresses. This study investigated the influence of the duration of a high-fat diet (HFD) in mice on tissue-specific cellular responses, specifically with regard to the role of autophagy and ER stress.

METHODS

Male mice aged 6-7 weeks were fed ad libitum with a standard chow diet or with a HFD for 2, 4, 8, or 16 weeks.

RESULTS

The HFD progressively increased mean body weight and induced tissue hypertrophy. The expression of PERK was suppressed in the liver after 16 weeks of the HFD and in the heart after 8 weeks of the HFD. Procaspase 12 and its activated form were induced in the liver with the HFD after 2 weeks, but not in the heart over the 16-week period. The activation of hepatic AMPK was elevated following 4 weeks of the HFD, but was inhibited after 16 weeks of the HFD. The ratio of LC3II to LC3I in the liver did not increase except in those mice fed the HFD for 16 weeks. The expression of AMPK and LC3 in the heart did not change over the entire 16 weeks of feeding the HFD. Cleaved PARP was increased in the liver and heart of mice receiving the HFD for 8 weeks.

CONCLUSIONS

This study provides evidence that a HFD affects the cellular protein quality control processes responsible for metabolic disorder in a tissue- and duration-dependent manner.

Review of the prognostic value of galectin-3 in heart failure focusing on clinical utility of repeated testing

Galectin-3 is a soluble β-galactoside-binding lectin released by activated cardiac macrophages. Elevated levels of galectin-3 have been found to be associated with adverse outcomes in patients with heart failure. A number of recent studies suggest that galectin-3 may provide relevant information regarding the pathophysiologic process of heart failure. We analyzed the most recent and comprehensive studies which are focused on the association between galectin-3 and heart failure. Galectin-3 has also been associated with acute and chronic heart failure. Although most of the studies involved patients with heart failure and systolic dysfunction, galectin-3 seems to have more accurate role in heart failure with preserved left ventricular ejection fraction. However, the mechanism of this relationship and its clinical implications remain uncertain. Some studies have not been able to prove the association between galectin-3 and heart failure, so there are many questions to answer. Galectin-3 has also been involved to renal dysfunction, so it could be a mediator of worsening renal function. Serial measurement of galectin-3 could provide further prognostic information in heart failure patients.

Differentially expressed microRNAs in maternal plasma for the noninvasive prenatal diagnosis of Down syndrome (trisomy 21)

OBJECTIVES

Most developmental processes are under the control of small regulatory RNAs called microRNAs (miRNAs). We hypothesize that different fetal developmental processes might be reflected by extracellular miRNAs in maternal plasma and may be utilized as biomarkers for the noninvasive prenatal diagnosis of chromosomal aneuploidies. In this proof-of-concept study, we report on the identification of extracellular miRNAs in maternal plasma of Down syndrome (DS) pregnancies.

METHODS

Using high-throughput quantitative PCR (HT-qPCR), 1043 miRNAs were investigated in maternal plasma via comparison of seven DS pregnancies with age and fetal sex matched controls.

RESULTS

Six hundred and ninety-five miRNAs were identified. Thirty-six significantly differentially expressed mature miRNAs were identified as potential biomarkers. Hierarchical cluster analysis of these miRNAs resulted in the clear discrimination of DS from euploid pregnancies. Gene targets of the differentially expressed miRNAs were enriched in signaling pathways such as mucin type-O-glycans, ECM-receptor interactions, TGF-beta, and endocytosis, which have been previously associated with DS.

CONCLUSIONS

miRNAs are promising and stable biomarkers for a broad range of diseases and may allow a reliable, cost-efficient diagnostic tool for the noninvasive prenatal diagnosis of DS.