Identification of stably expressed housekeeping miRNAs in endothelial cells and macrophages in an inflammatory setting

MiR-127-3p enhances macrophagic proliferation via disturbing fatty acid profiles and oxidative phosphorylation in atherosclerosis

BACKGROUND

Atherosclerosis is a chronic pathology, leading to acute coronary heart disease or stroke. MiR-127 has been found significantly upregulated in advanced atherosclerosis. But its function in atherosclerosis remains unexplored. We explored the role of miR-127-3p in regulating atherosclerosis development and its downstream mechanisms.

METHODS

The expression profile of miR-127 in carotid atherosclerotic plaques of 23 patients with severe carotid stenosis was detected by RT-qPCR and in situ hybridization. Primary bone marrow-derived macrophages (BMDM) stimulated with oxidized low-density lipoprotein were used as an in vitro model. CCK-8, EdU, RT-qPCR, and flow cytometry were used to detect the proliferative capacity and polarization of BMDM, which were infected by lentivirus-carrying plasmid to upregulate or downregulate miR-127-3p expression, respectively. RNA sequencing combined with bioinformatic analysis and targeted fatty acid metabolomics approach were used to detect the transcriptome and lipid metabolites. The association between miR-127-3p and its target was verified by dual-luciferase activity reporting and Western blotting. Oxygen consumption rate of BMDM were detected using seahorse analysis. High-cholesterol-diet-fed low density lipoprotein deficient (LDLR-/-) mice, with-or-without carotid tandem-stenosis surgery, were treated with miR-127-3p agomir or antagomir to examine its effect on plaque development and stability.

RESULTS

miR-127-3p, not -5p, is elevated in human advanced carotid atheroma and its expression is positively associated with macrophage accummulation in plaques. In vitro, miR-127-3p-overexpressed macrophage exhibites increased proliferation capacity and facilitates M1 polariztion whereas the contrary trend is present in miR-127-3p-inhibited macrophage. Stearoyl-CoA desaturase-1 (SCD1) is one potential target of miR-127-3p. miR-127-3p mimics decreases the activity of 3' untranslated regions of SCD-1. Furthermore, miR-127-3p downregulates SCD1 expression, and reversing the expression of SCD1 attenuates the increased proliferation induced by miR-127-3p overexpression in macrophage. miR-127-3p overexpression could also lead to decreased content of unsaturated fatty acids (UFAs), increased content of acetyl CoA and increased level of oxidative phosphorylation. In vivo, miR-127-3p agomir significantly increases atherosclerosis progression, macrophage proliferation and decreases SCD1 expression and the content of UFAs in aortic plaques of LDLR-/- mice. Conversely, miR-127-3p antagomir attenuated atherosclerosis, macrophage proliferation in LDLR-/- mice, and enhanced carotid plaque stability in mice with vulnerable plaque induced.

CONCLUSION

MiR-127-3p enhances proliferation in macrophages through downregulating SCD-1 expression and decreasing the content of unsaturated fatty acid, thereby promoting atherosclerosis development and decreasing plaque stability. miR-127-3p/SCD1/UFAs might provide potential therapeutic target for anti-inflammation and atherosclerosis.

miRNA-Mediated Fine Regulation of TLR-Induced M1 Polarization

Macrophage polarization to the M1 spectrum is induced by bacterial cell wall components through stimulation of Toll-like family (TLR) receptors. By orchestrating the expression of relevant mediators of the TLR cascade, as well as associated pathways and feedback loops, macrophage polarization is coordinated to ensure an appropriate immune response. This is central to the successful control of pathogens and the maintenance of health. Macrophage polarization is known to be modulated at both the transcriptional and post-transcriptional levels. In recent years, the miRNA-based post-transcriptional regulation of M1 polarization has received increasing attention from the scientific community. Comparative studies have shown that TLR stimulation alters the miRNA profile of macrophages and that macrophages from the M1 or the M2 spectrum differ in terms of miRNAs expressed. Simultaneously, miRNAs are considered critical post-transcriptional regulators of macrophage polarization. In particular, miRNAs are thought to play a regulatory role in the switch between the early proinflammatory response and the resolution phase. In this review, we will discuss the current state of knowledge on the complex interaction of transcriptional and post-transcriptional regulatory mechanisms that ultimately determine the functionality of macrophages.

Brain-Derived Exosomal miRNA Profiles upon Experimental SAE Rats and Their Comparison with Peripheral Exosomes

Sepsis-associated encephalopathy (SAE) is a diffuse brain dysfunction secondary to body infection without overt central nervous system infection. Dysregulation of miRNA expression in the transcriptome can spread through RNA transfer in exosomes, providing an early signal of impending neuropathological changes in the brain. Here, we comprehensively analyzed brain-derived exosomal miRNA profiles in SAE rats (n = 3) and controls (n = 3). We further verified the differential expression and correlation of brain tissue, cerebrospinal fluid, and plasma exosomal miRNAs in SAE rats. High-throughput sequencing of brain-derived exosomal miRNAs identified 101 differentially expressed miRNAs, of which 16 were downregulated and 85 were upregulated. Four exosomal miRNAs (miR-127-3p, miR-423-3p, mR-378b, and miR-106-3p) were differentially expressed and correlated in the brain tissue, cerebrospinal fluid, and plasma, revealing the potential use of miRNAs as SAE liquid brain biopsies. Understanding exosomal miRNA profiles in SAE brain tissue and exploring the correlation with peripheral exosomal miRNA can contribute to a comprehensive understanding of miRNA changes in the SAE pathological process and provide the possibility of establishing early diagnostic assays.

Transcriptom and miRNA data of PUFA-enriched stimulated murine macrophage and human endothelial cell lines

Inflammation is associated with the adaptation of macrophages and endothelial cells, and the dysregulation of these differentiation processes has been directly linked to both acute and chronic disease states. As cells in constant contact with blood, macrophages and endothelial cells are also under the direct influence of immunomodulatory dietary components such as polyunsaturated fatty acids (PUFA). RNA sequencing analyses allow us to understand the global changes in gene expression occurring during cell differentiation, including both transcriptional (transcriptome) and post-transcriptional (miRNAs) levels. We generated a comprehensive RNA sequencing dataset of parallel transcriptome and miRNA profiles of PUFA-enriched and pro-inflammatory stimulated macrophages and endothelial cells aiming to uncover the underlying molecular mechanisms. PUFA concentrations and duration of supplementation were based on dietary ranges, allowing for metabolism and plasma membrane uptake of fatty acids. The dataset may serve as a resource to study transcriptional and post-transcriptional changes associated with macrophage polarisation and endothelial dysfunction in inflammatory settings and their modulation by omega-3 and omega-6 fatty acids.

Initial development and testing of an exhaled microRNA detection strategy for lung cancer case-control discrimination

For detecting field carcinogenesis non-invasively, early technical development and case-control testing of exhaled breath condensate microRNAs was performed. In design, human lung tissue microRNA-seq discovery was reconciled with TCGA and published tumor-discriminant microRNAs, yielding a panel of 24 upregulated microRNAs. The airway origin of exhaled microRNAs was topographically "fingerprinted", using paired EBC, upper and lower airway donor sample sets. A clinic-based case-control study (166 NSCLC cases, 185 controls) was interrogated with the microRNA panel by qualitative RT-PCR. Data were analyzed by logistic regression (LR), and by random-forest (RF) models. Feasibility testing of exhaled microRNA detection, including optimized whole EBC extraction, and RT and qualitative PCR method evaluation, was performed. For sensitivity in this low template setting, intercalating dye-based URT-PCR was superior to fluorescent probe-based PCR (TaqMan). In application, adjusted logistic regression models identified exhaled miR-21, 33b, 212 as overall case-control discriminant. RF analysis of combined clinical + microRNA models showed modest added discrimination capacity (1.1-2.5%) beyond clinical models alone: all subjects 1.1% (p = 8.7e-04)); former smokers 2.5% (p = 3.6e-05); early stage 1.2% (p = 9.0e-03), yielding combined ROC AUC ranging from 0.74 to 0.83. We conclude that exhaled microRNAs are qualitatively measureable, reflect in part lower airway signatures; and when further refined/quantitated, can potentially help to improve lung cancer risk assessment.

miR‑151a‑5p promotes the proliferation and metastasis of colorectal carcinoma cells by targeting AGMAT

Colorectal carcinoma (CRC) is one of the most common types of digestive cancer. It has been reported that the ectopic expression of microRNAs (miRs) plays a critical role in the occurrence and progression of CRC. In addition, it has also been suggested that miR‑151a‑5p may serve as a useful biomarker for the early detection and treatment of different types of cancer and particularly CRC. However, the specific effects and underlying mechanisms of miR‑151a‑5p in CRC remain elusive. The results of the current study demonstrated that miR‑151a‑5p was upregulated in CRC cell lines and clinical tissues derived from patients with CRC. Functionally, the results showed that miR‑151a‑5p significantly promoted CRC cell proliferation, migration and invasion. Additionally, dual luciferase reporter assays verified that agmatinase (AGMAT) was a direct target of miR‑151a‑5p and it was positively associated with miR‑151a‑5p expression. Mechanistically, miR‑151a‑5p could enhance the epithelial‑mesenchymal transition of CRC cells. Taken together, the results of the current study revealed a novel molecular mechanism indicating that the miR‑151a‑5p/AGMAT axis could serve a crucial role in the regulation of CRC and could therefore be considered as a potential therapeutic strategy for CRC.

The diagnostic significance of circulating miRNAs and metabolite profiling in early prediction of breast cancer in Egyptian women

Objective

Breast cancer (BC) is one of the most commonly diagnosed solid malignancies in women worldwide.

Purpose

Finding new non-invasive circulating diagnostic biomarkers will facilitate the early prediction of BC and provide valuable insight into disease progression and response to therapy using a safe and more accessible approach available every inspection time. Therefore, our present study aimed to investigate expression patterns of potentially circulating biomarkers that can differentiate well between benign, malignant, and healthy subjects.

Methods

To achieve our target, quantitative analyses were performed for some circulating biomarkers which have a role in the proliferation and tumor growth, as well as, glutamic acid, and human epidermal growth receptor 2 (HER2) in blood samples of BC patients in comparison to healthy controls using qRT-PCR, liquid chromatography/mass spectrometry (LC/MS/MS), and ELISA.

Results

Our findings showed that the two miRNAs (miRNA-145, miRNA-382) were expressed at lower levels in BC sera than healthy control group, while miRNA-21 was expressed at higher levels in BC patients than control subjects. Area under ROC curves of BC samples revealed that AUC of miRNA-145, miRNA-382, miRNA-21, and glutamic acid was evaluated to equal 0.99, 1.00, 1.00 and 1.00, respectively. Besides, there was a significantly positive correlation between miRNA-145 and miRNA-382 (r = 0.737), and a highly significant positive correlation between miRNA-21 and glutamic acid (r = 0.385).

Conclusion

Based on our results, we conclude that the detection of serum miRNA-145, -382 and -21 as a panel along with glutamic acid, and circulating HER2 concentrations could be useful as a non-invasive diagnostic profiling for early prediction of breast cancer in Egyptian patients. It can provide an insight into disease progression, discriminate between malignancy and healthy control, and overcome the use limitations (low sensitivity and specificity, repeated risky exposure, and high cost) of other detecting tools, including mammography, magnetic resonance imaging, and ultrasound.

RETRACTED: Exosomal microRNA-16-5p from adipose mesenchymal stem cells promotes TLR4-mediated M2 macrophage polarization in septic lung injury

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). The authors have requested that this paper be retracted as they were unable to replicate the experimental data reported in Figure 1A. The authors posit that changes in reagents or experimental conditions might be the source of their inability to do so. Additional concerns were raised about the reliability of the Western blot results in Figure 1E, Figure 4B and F, Figure 5B, and Figure 6B, as regarding ‘morphology space’ similarities contained within a series of papers with distinctive eyebrow blots, tabulated here (https://docs.google.com/spreadsheets/d/149EjFXVxpwkBXYJOnOHb6RhAqT4a2llhj9LM60MBffM/edit#gid=0 [nam11.safelinks.protection.outlook.com] [nam11.safelinks.protection.outlook.com]). The journal requested the authors comment on these concerns and provide raw data. However, the authors were not able to fulfil this request and therefore the Editor-in-Chief decided to retract the article.

Endothelial Exosome Plays a Functional Role during Rickettsial Infection

Spotted fever group rickettsioses (SFRs) are devastating human infections. Vascular endothelial cells (ECs) are the primary targets of rickettsial infection. Edema resulting from EC barrier dysfunction occurs in the brain and lungs in most cases of lethal SFR, but the underlying mechanisms remain unclear. The aim of the study was to explore the potential role of Rickettsia-infected, EC-derived exosomes (Exos) during infection. Using size exclusion chromatography (SEC), we purified Exos from conditioned, filtered, bacterium-free media collected from Rickettsia parkeri-infected human umbilical vein ECs (HUVECs) (R-ECExos) and plasma of Rickettsia australis- or R. parkeri-infected mice (R-plsExos). We observed that rickettsial infection increased the release of heterogeneous plsExos, but endothelial exosomal size, morphology, and production were not significantly altered following infection. Compared to normal plsExos and ECExos, both R-plsExos and R-ECExos induced dysfunction of recipient normal brain microvascular ECs (BMECs). The effect of R-plsExos on mouse recipient BMEC barrier function is dose dependent. The effect of R-ECExos on human recipient BMEC barrier function is dependent on the exosomal RNA cargo. Next-generation sequencing analysis and stem-loop quantitative reverse transcription-PCR (RT-qPCR) validation revealed that rickettsial infection triggered the selective enrichment of endothelial exosomal mir-23a and mir-30b, which potentially target the endothelial barrier. To our knowledge, this is the first report on the functional role of extracellular vesicles following infection by obligately intracellular bacteria.

Sepsis Diagnostics: Intensive Care Scoring Systems Superior to MicroRNA Biomarker Testing

Sepsis represents a serious medical problem accounting for numerous deaths of critically ill patients in intensive care units (ICUs). An early, sensitive, and specific diagnosis is considered a key element for improving the outcome of sepsis patients. In addition to classical laboratory markers, ICU scoring systems and serum miRNAs are discussed as potential sepsis biomarkers. In the present prospective observational study, the suitability of miRNAs in sepsis diagnosis was tested based on proper validated and normalized data (i.e., absolute quantification by means of Droplet Digital PCR (ddPCR)) in direct comparison to classical sepsis markers and ICU scores within the same patient cohort. Therefore, blood samples of septic intensive care patients (n = 12) taken at day of admission at ICU were compared to non-septic intensive care patients (n = 12) and a healthy control group (n = 12). Our analysis indicates that all tested biomarkers have only a moderate informative power and do not allow an unequivocal differentiation between septic and non-septic ICU patients. In conclusion, there is no standalone laboratory parameter that enables a reliable diagnosis of sepsis. miRNAs are not superior to classical parameters in this respect. It seems recommendable to measure multiple parameters and scores and to interpret them with regard to the clinical presentation.