Diagnosis of acute myocardial infarction: CK-MB versus cTn-T in Indian patients

Identification of important genes associated with acute myocardial infarction using multiple cell death patterns

Acute myocardial infarction (AMI) is a global health threat, and programmed cell death (PCD) plays a crucial role in its occurrence and development. In this study, integrated bioinformatics tools were used to explore new biomarkers and therapeutic targets in AMI. Thirteen types of PCD-related genes were identified through literature review, KEGG, and GSEA pathways. Gene expression matrices and clinical data from AMI patients and healthy controls were obtained from the GEO database. Statistical analysis in R identified 377 differentially expressed genes in AMI patients. Intersection analysis between the differentially expressed genes and PCD-related genes revealed 24 genes positively correlated with immune cells such as Neutrophils and Monocytes, while negatively correlated with T cells CD4 memory resting and Plasma cells. Unsupervised clustering analysis divided patients into two groups (C1 and C2) based on the expression levels of these 24 genes. GSVA analysis showed that C2 patients were more active in pathways related to maintaining normal cell morphology and promoting phagocytosis, suggesting a lower programmed cell death rate and a higher tendency to maintain cell survival. Two hub genes, TNFAIP3 and TP53INP2, were identified through LASSO regression analysis and SVM-RFE, and were validated using an external dataset and RT-qPCR、Western blot and ELISA analysis. These hub genes showed significantly higher expression and protein secretion levels in AMI patients compared to healthy individuals. Overall, regulating and controlling PCD, particularly through the identified hub genes, TNFAIP3 and TP53INP2, may provide new therapeutic strategies for improving the prognosis of AMI patients and preventing heart failure.

Identification and analysis of key genes associated with acute myocardial infarction by integrated bioinformatics methods

BACKGROUND

Acute myocardial infarction (AMI) is a common disease leading threat to human health around the world. Here we aimed to explore new biomarkers and potential therapeutic targets in AMI through adopting integrated bioinformatics tools.

METHODS

The gene expression Omnibus (GEO) database was used to obtain genes data of AMI and no-AMI whole blood. Furthermore, differentially expressed genes (DEGs) were screened using the "Limma" package in R 3.6.1 software. Functional and pathway enrichment analyses of DEGs were performed via "Bioconductor" and "GOplot" package in R 3.6.1 software. In order to screen hub DEGs, the STRING version 11.0 database, Cytoscape and molecular complex detection (MCODE) were applied. Correlation among the hub DEGs was evaluated using Pearson's correlation analysis.

RESULTS

By performing DEGs analysis, 289 upregulated and 62 downregulated DEGs were successfully identified from GSE66360, respectively. And they were mainly enriched in the terms of neutrophil activation, immune response, cytokine, nuclear factor kappa-B (NF-κB) signaling pathway, IL-17 signaling pathway, and tumor necrosis factor (TNF) signaling pathway. Based on the data of protein-protein interaction (PPI), the top 10 hub genes were ranked, including interleukin-8 (CXCL8), TNF, N-formyl peptide receptor 2 (FPR2), growth-regulated alpha protein (CXCL1), transcription factor AP-1 (JUN), interleukin-1 beta (IL1B), platelet basic protein (PPBP), matrix metalloproteinase-9 (MMP9), toll-like receptor 2 (TLR2), and high affinity immunoglobulin epsilon receptor subunit gamma (FCER1G). What's more, the results of correlation analysis demonstrated that there was positive correlation between the 10 hub DEGs.

CONCLUSION

Ten DEGs were identified as potential candidate diagnostic biomarkers for patients with AMI in present study. However, further experiments are needed to confirm the functional pathways and hub genes associated with AMI.

Ameliorating role of whey syrup against ageing-related damage of myocardial muscle of Wistar Albino rats

Age-ing is involved in gradual breakdown of biological structure and function of body organs. The heart represents the main organ responsible for pumping the main issues of life which involving oxygen, nutrients and bioactive molecules necessary for maintaining the body functions. The present study has been conducted to assess the anti-aging properties of whey syrup collected from fermented milk in 4, 18 and 30-months-old rats. The histopathological and histochemical changes of carbohydrates and proteins were investigated. Immunohistochemical expression of smooth muscle actin and P53 was performed to assess the function of cardiomyocytes. Furthermore, Annexin v and biochemical changes of different cardio-biomarkers were carried out to evaluate the effects of aging. The present result of 30 months-old rats revealed myocardial infarction assessed by widening of myocardial fibers, diffused with numerous blood capillaries and dense leukocytic infiltration. The assessed biochemical markers confirmed myocardial damage. Whey supplementation improved the myocardial structure, but less improvement was observed for the 30-months-old rats. The author recommended supplementation with whey is beneficial in giving a body the demand for amino acids and minerals essential for supporting the myocardium and also provides protection against age-ing.

RETRACTED: Cadmium induced cardiac oxidative stress in rats and its attenuation by GSP through the activation of Nrf2 signaling pathway

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Western Blots from Figures 8B and 9A appear similar to Blots from Figure 4A of the article previously published by the authors in Biochemistry and Cell Biology 93 (2015) 210-226 https://doi.org/10.1139/bcb-2014-0114 and Figures 12 and 14 of the article previously published by the corresponding author et al in Biomedicine & Preventive Nutrition 4 (2014) 561-577 https://doi.org/10.1016/j.bionut.2014.08.003, although the Western Blots purportedly described different samples. Also, sections within the panels from Figures 10 and 11D appear unusually similar to each other. The explanation provided by the corresponding author was not satisfactory and the Editor decided to retract the article.

Epigallocatechin gallate potentially attenuates Fluoride induced oxidative stress mediated cardiotoxicity and dyslipidemia in rats

The present study was undertaken to evaluate the cardioprotective role of (-)-epigallocatechin-gallate (EGCG) against Fluoride (F) induced oxidative stress mediated cardiotoxicity in rats. The animals exposed to F as sodium Fluoride (NaF) (25mg/kg BW) for 4 weeks exhibited a significant increase in the levels of cardiac troponins T and I (cTnT & I), cardiac serum markers, lipid peroxidative markers and plasma total cholesterol (TC), triglycerides (TG), phospholipids (PL), free fatty acids (FFA), low density lipoprotein cholesterol, very low density lipoprotein cholesterol as well as cardiac lipids profile (TC, TG and FFA) with the significant decrease of high density lipoprotein cholesterol and cardiac phospholipids. F intoxication also decreased the levels of mitochondrial enzymes such as ICDH, SDH, MDH, α-KGDH and NADH in the cardiac tissue of rats. The mitochondrial Ca(2+) ion level was also significantly reduced along with the significant decrease in the levels of enzymatic and non enzymatic antioxidants. Furthermore, F treatment significantly increased the DNA fragmentation, up regulate cardiac pro-apoptotic markers, inflammatory markers and down-regulate the anti-apoptotic markers in the cardiac tissue. Pre administration of EGCG (40mg/kg/bw) in F intoxicated rats remarkably recovered all these altered parameters to near normalcy through its antioxidant nature. Thus, results of the present study clearly demonstrated that treatment with EGCG prior to F intoxication has a significant role in protecting F-induced cardiotoxicity and dyslipidemia in rats.

Elevated adropin: a candidate diagnostic marker for myocardial infarction in conjunction with troponin-I

Myocardial infarction (MI; "heart attack") can cause injury to or death of heart muscle tissue (myocardium) owing to prolonged ischemia and hypoxia. Troponins and CK-MB are released from heart muscle cells during MI. It has been demonstrated that energy expenditure is regulated by adropin expressed in the endocardium, myocardium, and epicardium. We hypothesized that adropin is released into the bloodstream during myocardial muscle injury caused by MI, so the serum level rises as myocytes die. Therefore, we examined the association between adropin expression and myocardial infarction in isoproterenol-induced myocardial infarction. Rats were randomly allocated to six groups. After treatment they were decapitated and their blood and tissues were collected for adropin measurement. Changes in adropin synthesis in rat heart, kidney and liver tissues in isoproterenol (ISO)-induced MI were demonstrated immunohistochemically. Serum adropin concentrations were measured by ELISA, and troponin-I, CK and CK-MB concentrations by autoanalysis. The results demonstrated that cardiac muscle cells, glomerular, peritubular and renal cortical interstitial cells, hepatocytes and liver sinusoidal cells all synthesize adropin, and synthesis increased 1-24 h after MI except in the liver cells. The findings elucidate the pathogenesis of MI, and the gradual increase in serum adropin could be a novel diagnostic marker and serve as an alternative to troponin-I measurement for diagnosing MI.

Circulating microRNAs as novel biomarkers for the early diagnosis of acute coronary syndrome

Small non-coding microRNAs (miRNAs) are important physiological regulators of post-transcriptional gene expression. miRNAs not only reside in the cytoplasm but are also stably present in several extracellular compartments, including the circulation. For that reason, miRNAs are proposed as diagnostic biomarkers for various diseases. Early diagnosis of acute coronary syndrome (ACS), especially non-ST elevated myocardial infarction and unstable angina pectoris, is essential for optimal treatment outcome, and due to the ongoing need for additional identifiers, miRNAs are of special interest as biomarkers for ACS. This review highlights the nature and cellular release mechanisms of circulating miRNAs and therefore their potential role in the diagnosis of myocardial infarction. We will give an update of clinical studies addressing the role of circulating miRNA expression after myocardial infarction and explore the diagnostic value of this potential biomarker.

Effect of ursolic acid treatment on apoptosis and DNA damage in isoproterenol-induced myocardial infarction

The present study was designed to evaluate the protective effect of ursolic acid (UA) against isoproterenol-induced myocardial infarction. Myocardial infarction was induced by subcutaneous injection of isoproterenol hydrochloride (ISO) (85 mg/kg BW), for two consecutive days. ISO-induced rats showed elevated levels of cardiac troponins T (cTn T) and I (cTn I) and increased activity of creatine kinase-MB (CK-MB) in serum. Lipid peroxidative markers (thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and lipid hydroperoxides (HP)) elevated in the plasma and heart tissue whereas decreased activities of enzymatic antioxidants (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and glutathione reductase (GR)) in erythrocytes and heart tissue of ISO-induced rats. Non-enzymatic antioxidants (vitamin C, vitamin E and reduced glutathione (GSH)) levels were decreased significantly in the plasma and heart tissue of ISO-induced rats. Furthermore, ISO-induced rats showed increased DNA fragmentation, upregulations of myocardial pro-apoptotic B-cell lymphoma-2 associated-x (Bax), caspase-3, -8 and -9, cytochrome c, tumor necrosis factor-α (TNF-α), Fas and down-regulated expressions of anti-apoptotic B-cell lymphoma-2 (Bcl-2) and B-cell lymphoma-extra large (Bcl-xL). UA-administered rats showed decreased levels/activity of cardiac markers, DNA fragmentation and the levels of lipid peroxidative markers in the plasma and heart tissue. Activities of enzymatic antioxidants were increased significantly in the erythrocytes and heart tissue and also non-enzymatic antioxidants levels were increased significantly in the plasma and heart tissue in UA-administered rats. UA influenced decreased DNA fragmentation and an apoptosis by upregulation of anti-apoptotic proteins such as Bcl-2, Bcl-xL and down-regulation of Bax, caspase-3, -8 and -9, cytochrome c, TNF-α, Fas through mitochondrial pathway. Histopathological observations were also found in line with biochemical parameters. Thus, results of the present study demonstrated that the UA has anti-apoptotic properties in ISO-induced rats.

Surface plasmon resonance aided electrochemical immunosensor for CK-MB determination in undiluted serum samples

This article presents a simple chronoamperometric immunosensor for the quantitative assessment of creatine kinase MB (CK-MB) in 50 microL undiluted serum samples. The immunosensor consists of gold working and counter electrodes patterned onto a glass chip by thin-film photolithography and an external Ag|AgCl reference electrode. The detection limit (DL) of the chronoamperometric method is 13 ng mL(-1) (DL = 2xRMSD/S, where RMSD is the residual mean standard deviation of the measured points around a calibration curve with a slope of S). In spiked serum samples, the response was linear up to 300 ng mL(-1) of CK-MB. A surface plasmon resonance (SPR) system with simultaneous electrochemical detection (EC-SPR) aided the development of the sandwich immunoassay. Real-time monitoring of the SPR signal was used to optimize the capture antibody immobilization, CK-MB and detection antibody binding, as well as to minimize the nonspecific adsorption of serum proteins to the sensor surface. The detection antibody has been labeled with alkaline phosphatase (ALP) enzyme for sensitive electrochemical detection. ALP catalyzes the hydrolysis of ascorbic acid phosphate and generates ascorbic acid, which is measured chronoamperometrically. The electrochemical immunoassay for CK-MB was less sensitive to nonspecific adsorption related interferences, had a better detection limit, and required a lower volume of sample than the SPR method.