Analysis of Serum MicroRNAs as Potential Biomarker in Coronary Bifurcation Lesion

Downregulation of circulating miR-320a and target gene prediction in patients with diabetic retinopathy

Objective

To evaluate the expression of a set of miRNAs to identify differentially expressed miRNAs that might be considered reliable biomarkers on Diabetic Retinopathy (DR) blood samples.

Results

Expression levels of MiR-320a, MiR-342-3p, MiR-155, MiR-99a, MiR-29a and MiR-27b were analyzed in 60 healthy controls, 48 Diabetes Melitus (DM) without DR patients and 62 DR patients by qRT-PCR. MiR-320a was shown to be downregulated in the plasma of DR patients compared with DM patients without DR and healthy subjects. Target genes were predicted using miRWalk3.0, miR targeting data and target gene interaction data were imported to Cytoscape to visualize and merge networks and top ranked predicted genes were run through Ontology Genes to perform enrichment analysis on gene sets and classification system to identify biological processes and reactome pathways associated with DR. Highly scored target genes of miR-320a were categorized for various biological processes, including negative regulation of cell aging, negative regulation of cellular protein metabolic process and regulation of cellular response to stress that are critical to the development of DR. Our findings suggest that MiR-320a may have a role in the pathogenesis of DR and may represent novel biomarkers for this disease.

Identification of miR-328-3p as an endogenous reference gene for the normalization of miRNA expression data from patients with Diabetic Retinopathy

Diabetic Retinopathy, the main cause of visual loss and blindness among working population, is a complication of Diabetes mellitus (DM), which has been described as a major public health challenge, so it is important to identify biomarkers to predict and to stratify patient´s possibility for developing DR. MicroRNAs (miRNAs) are small non-coding RNA molecules that have showed to be promising disease biomarkers and association of miRNAs with the possibility to develop DR has been reported. However, evaluating miRNA expression involves normalization of RT-qPCR data using internal reference genes that should be properly determined, considering their impact on expression levels calculation and, until date, there is no unanimity on reference miRNAs for the investigation of circulating miRNAs in DR. We aimed to estimate the appropriateness of a group of miRNAs as normalizers to identify which might be considered steady internal reference genes in expression studies on DR plasma samples. Expression levels of candidates were analyzed in 60 healthy controls, 48 DM without DR patients and 62 DR patients with two statistical tools: NormFinder and RefFinder. MiR-328-3p was the most stable gene and we also investigated the effect of gene normalization, demonstrating that different normalization strategies have important implications for accurate data interpretation.

Circulating microRNAs as possible biomarkers for coronary artery disease: a narrative review

Coronary artery disease is one of the most common cardiovascular diseases in the world. Involvement of microRNAs on the pathogenesis of this disease was reported either in beneficial or detrimental way. Different studies have also speculated that circulating microRNAs can be applied as promising biomarkers for the diagnosis of coronary artery disease. Particularly, microRNA-133a seems to fulfill the criteria of ideal biomarkers due to its role in the diagnosis, severity assessment and in prognosis. The panel of circulating microRNAs has also improved the predictive power of coronary artery disease compared to single microRNAs. In this review, the role of circulating microRNAs for early detection, severity assessment and prognosis of coronary artery disease were reviewed.

High-throughput approaches for screening and analysis of cell behaviors

The rapid development of new biomaterials and techniques to modify them challenge our capability to characterize them using conventional methods. In response, numerous high-throughput (HT) strategies are being developed to analyze biomaterials and their interactions with cells using combinatorial approaches. Moreover, these systematic analyses have the power to uncover effects of delivered soluble bioactive molecules on cell responses. In this review, we describe the recent developments in HT approaches that help identify cellular microenvironments affecting cell behaviors and highlight HT screening of biochemical libraries for gene delivery, drug discovery, and toxicological studies. We also discuss HT techniques for the analyses of cell secreted biomolecules and provide perspectives on the future utility of HT approaches in biomedical engineering.

Analysis of circulating microRNAs in patients with repaired Tetralogy of Fallot with and without heart failure

BACKGROUND

MicroRNAs (miRNAs) are a class of regulatory RNAs that regulate gene expression post-transcriptionally. Little, however, is known on the expression profile of circulating miRNAs in Tetralogy of Fallot (TOF) patients late after surgical repair. In this study, we aimed to identify the specific patterns of circulating miRNAs in blood of patients with repaired, non-syndromic TOF and to assess whether these specific miRNAs may be useful to differentiate patients with and without heart failure.

METHODS

SurePrint™ 8 × 60 K Human v16 miRNA arrays were used to determine miRNA expression profiles in 15 healthy controls and 37 patients after TOF repair of whom 3 had symptomatic right heart failure. The expression levels of selected miRNAs have been validated by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Enrichment analyses of altered miRNA expression were predicted using bioinformatic tools.

RESULTS

Compared with healthy controls, a total of 49, 58 and 77 miRNAs were found to be significantly altered in TOF patients (TOF-all), TOF patients with (TOF-HF) and without symptomatic right heart failure (TOF-noHF) (>2.0-fold change, adjusted P < 0.05), respectively. Three miRNAs namely miR-181d-5p, miR-206 and miR-625-5p were validated by RT-qPCR in all TOF groups. The area under the receiver operating characteristic curve (AUC) for miR-181d-5p, miR-206 and miR-625-5p were 0.987, 0.993 and 0.769 in TOF-all and 0.990, 0.994 and 0.749 in TOF-noHF, respectively. Moreover, expression levels of miR-625-5p, miR-1233-3p and miR-421 were lower in TOF-HF compared to TOF-noHF (P = 0.012).

CONCLUSIONS

Altered expression levels of circulating miRNAs were found in TOF patients late after surgical repair and are different to those seen in the right ventricular myocardium of infants with TOF. Expression levels of miR-421, miR-1233-3p and miR-625-5p are lower in TOF patients with symptomatic right heart failure and thus may indicate disease progression in these patients.