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Background: Identification of molecular markers, such as miRNAs is promising for the diagnosis of asthma and its clinical phenotypes. The aim of this study was to examine the changes in the expression of selected microRNAs in plasma exosomal fractions of severe asthma patients. The expression of miRNAs was determined in relation to the changes in inflammatory markers. Method: Severe asthma patients (n = 30) and healthy subjects (n = 30) were selected among the individuals referred to asthma and allergy clinic. Blood was collected from each participant to determine the serum high-sensitive C-reactive protein (hs-CRP) and total IgE. The exosomal fraction of plasma was isolated and processed for quantitation of miR-124, miR-125b, miR-133b, miR-130a and miR-125b-1-3p expression using quantitative real time-PCR (qRT-PCR). Results: Serum hs-CRP and total IgE were significantly higher in asthma patients compared to controls. Expression of miR-124, miR-133b, and miR-130a was down-regulated in asthma patients as compared to controls (p < 0.0001). However, the expression of miR-125b was substantially higher in patients compared to controls (p < 0.0001). There was no significant difference in the expression of miR-125b-1-3p in the patients and controls. Data analysis revealed that among the miRNAs, changes in miR-125b in severe asthma patients were highly correlated with the serum levels of hs-CRP and IgE. Conclusion: Overexpression of miR-125b in severe asthma which was associated with serum IgE and hs-CRP may suggest that this molecule is linked to inflammatory reactions. Up-regulation of miR-125b together with decreased expression of miR-124, miR-133b, and miR-130a may suggest that this miRNA profile is useful for diagnosis and discrimination of clinical phenotypes of asthma. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) remains a major threat to human health. Understanding the strategies mycobacteria take to overcome immune defense is important in order to control the infection. Micro (mi)RNAs are master regulators of most pathways in the human body.  Infection with mycobacterium impacts upon the host metabolic pathways as they are subverted to obtain the nutrition for intracellular TB survival. In this study, we aimed to investigate the effect of Bacillus Calmette-Guérin (BCG) infection on the expression of three miRNAs (miR-1224, -484 and -425), which are important in infection and in the regulation of metabolic pathways. Peripheral blood monocyte-derived macrophage (MDM) cultures were prepared and infected with BCG at a multiplicity of infection (MOI)=10 or left uninfected as a control. 72h post-infection, RNA was extracted from the cultured cells and cDNA synthesis and real-time PCR performed. Expression levels miRNAs were normalized to the levels of U6 snRNA (Rnu6) using the 2-ΔΔCt method. Infection with BCG resulted in a highly significant increase in miR-1224 expression (24.4±3.8-fold induction) in human MDMs. The induction of miR-484 (1.8±0.3-fold increase) and of miR-425 (1.2±0.2-fold increase) was less increased compared to miR-1224. Mycobacterium tolerates a hostile microenvironment by escaping from lysosomal degradation and providing a lipid-rich niche by trigger with and re-pattering host metabolism. This study highlighted the potential roles of miRNAs in host responses upon mycobacterium infection. [ABSTRACT FROM AUTHOR]

Background: Tuberculosis (TB) remains a significant global health concern and its diagnosis is challenging due to the limitations in the specificity and sensitivity of the current diagnostic tests. Exosomes are bioactive 30-100 nm vesicles produced by most cell types and are found in almost all human body fluids. Exosomal microRNAs (miRNAs) can transfer biological information between cells and tissues and may act as potential biomarkers in many diseases. In this pilot study, we assessed the miRNA profile of exosomes released from human monocyte-derived macrophages upon infection with Mycobacterium bovis Bacillus Calmette-Guerin (BCG).Methods: Human monocytes were obtained from the peripheral blood of three healthy subjects and driven to a monocyte-derived macrophage (MDM) phenotype using standard protocols. MDMs were infected with BCG or left uninfected as control. 72 h post-infection, exosomes were collected from the cell culture medium, RNA was isolated and RNA-seq performed. The raw reads were filtered to eliminate adaptor and primer sequences and the sequences were run against the mature human miRNA sequences available in miRBase. MicroRNAs were identified using an E value <0.01. miRNA network analysis was performed using the DIANA miRNA tool, miRDB and functional KEGG pathway analysis.Results: Infection of MDMs with BCG leads to the release of several exosomal miRNAs. These included miR-1224, -1293, -425, -4467, -4732, -484, -5094, -6848-6849, -4488 and -96 all of which were predicted to target metabolism and energy production-related pathways.Conclusions: This study provides evidence for the release of specific exosomal miRNAs from BCG-infected MDMs. These exosomal miRNAs reflect host-pathogen interaction and subversion of host metabolic processes following infection. [ABSTRACT FROM AUTHOR]

In this study, we first tried to determine whether the expression level of 9 miRNAs in the peripheral blood CD8+ T cells of asthmatic patients varies from that of controls, and secondly, we investigated the effects of fluticasone furoate and vilanterol on the expression level of these miRNAs. Fifteen subjects including 8 healthy individuals and 7 asthmatic patients were included in this study. CD8+T cells were isolated from participants' peripheral blood by a negative selection method using magnetic-activated cell sorting (MACS). The expression of 9 miRNAs was examined between the healthy individuals and asthmatic patients. Then the expression level of 9 miRNAs before and after treatment with the drugs was examined by quantitative real-time PCR. No significant changes in the expression level of 9 miRNAs were observed in asthmatic patients compared to the healthy controls. Fluticasone and vilanterol, in combination, had the greatest effect on miRNA expression. MiR-150 and miR-106a were the most and the least miRNAs, respectively, present in CD8+ T cells of patients and controls. MiR-106a and miR-126 had a positive correlation in CD8+ cells of asthmatic patients. Although no significant difference in the expression level of studies miRNAs was observed, the correlations among miRNAs were significant. Therefore, we suggest that the correlation between miRNAs would be a very important factor in physiological and pathological conditions in healthy individuals and asthmatic patients. Such a miRNA-miRNA correlation network can be even more critical than any changes in the variation of their expression in the CD8+ T cells. [ABSTRACT FROM AUTHOR]

Introduction. Tuberculosis (TB) remains a major threat to human health. Due to the limited accuracy of the current TB diagnostic tests, it is critical to determine novel biomarkers for this disease. Circulating exosomes have been used as diagnostic biomarkers in various diseases. Objective of the Study. In this pilot study, we examined the expression of miRNAs as biomarker candidates for the diagnosis of TB infection. Methods. Serum-derived exosomes were isolated from TB patients and matched control subjects. The expression of miR-484, miR-425, and miR-96 was examined by RT-PCR methods. Results. The expression of miR-484, miR-425, and miR-96 were significantly increased in serum of TB patients which correlated with the TB infection level. A receiver operating characteristic (ROC) curve analysis showed the diagnostic potency of each individual serum exosomal miRNA with an area under the curve AUC=0.72 for miR-484 (p<0.05), 0.66 for miR-425 (p<0.05), and 0.62 for miR-96 (p<0.05). Conclusion. These results demonstrate that exosomal miRNAs have diagnostic potential in active tuberculosis. The diagnostic power may be improved when combined with conventional diagnostic markers. [ABSTRACT FROM AUTHOR]

Introduction. miRNAs contribute to a variety of essential biological processes including development, proliferation, differentiation, and apoptosis. Circulating microRNAs are very stable and have shown potential as biomarkers of cardiovascular disease. microRNA-208b expression was increased in the blood of patients with acute myocardial infarction (AMI) and has been proposed as a biomarker for early diagnosis. In this pilot study, we investigate the potential of circulating miR-208b as a prognostic biomarker of 6-month survival in AMI patients. Methods. Plasma samples from 21 patients and 8 age- and gender-matched healthy adults were collected, and circulating levels of miR-208b were detected using quantitative real-time PCR. Results. miR-208b levels were higher in healthy control subjects (9.6-fold; P≤0.05). Within the AMI patients, the levels of miR-208b were significantly lower in the survivor versus nonsurvivor group (fold change = 6.51 and 14.1, resp.; P≤0.05). The Kaplan-Meier curve revealed that the 6-month survival time was significantly higher among AMI patients with a relative expression of miR-208b lower than 12.38. The hazard ratio (HR) for the relative expression of miR-208b (<12.38 was the reference) was 5.08 (95% CI: 1.13–22.82; P=0.03). Conclusion. Our results showed that elevated miR-208b expression was associated with reduced long-term survival in AMI patients. These pilot data indicate the need for a large follow-up study to confirm whether miR-208b can be used as a predictor of 6-month survival time after AMI. [ABSTRACT FROM AUTHOR]