Circulating microRNA-29-5p can add to the discrimination between dilated cardiomyopathy and ischaemic heart disease

MicroRNAs: Midfielders of Cardiac Health, Disease and Treatment

MicroRNAs (miRNAs) are a class of small non-coding RNA molecules that play a role in post-transcriptional gene regulation. It is generally accepted that their main mechanism of action is the negative regulation of gene expression, through binding to specific regions in messenger RNA (mRNA) and repressing protein translation. By interrupting protein synthesis, miRNAs can effectively turn genes off and influence many basic processes in the body, such as developmental and apoptotic behaviours of cells and cardiac organogenesis. Their importance is highlighted by inhibiting or overexpressing certain miRNAs, which will be discussed in the context of coronary artery disease, atrial fibrillation, bradycardia, and heart failure. Dysregulated levels of miRNAs in the body can exacerbate or alleviate existing disease, and their omnipresence in the body makes them reliable as quantifiable markers of disease. This review aims to provide a summary of miRNAs as biomarkers and their interactions with targets that affect cardiac health, and intersperse it with current therapeutic knowledge. It intends to succinctly inform on these topics and guide readers toward more comprehensive works if they wish to explore further through a wide-ranging citation list.

miRNA Dysregulation in Cardiovascular Diseases: Current Opinion and Future Perspectives

MicroRNAs (miRNAs), small noncoding RNAs, are post-transcriptional gene regulators that can promote the degradation or decay of coding mRNAs, regulating protein synthesis. Many experimental studies have contributed to clarifying the functions of several miRNAs involved in regulatory processes at the cardiac level, playing a pivotal role in cardiovascular disease (CVD). This review aims to provide an up-to-date overview, with a focus on the past 5 years, of experimental studies on human samples to present a clear background of the latest advances to summarize the current knowledge and future perspectives. SCOPUS and Web of Science were searched using the following keywords: (miRNA or microRNA) AND (cardiovascular diseases); AND (myocardial infarction); AND (heart damage); AND (heart failure), including studies published from 1 January 2018 to 31 December 2022. After an accurate evaluation, 59 articles were included in the present systematic review. While it is clear that miRNAs are powerful gene regulators, all the underlying mechanisms remain unclear. The need for up-to-date data always justifies the enormous amount of scientific work to increasingly highlight their pathways. Given the importance of CVDs, miRNAs could be important both as diagnostic and therapeutic (theranostic) tools. In this context, the discovery of “TheranoMIRNAs” could be decisive in the near future. The definition of well-setout studies is necessary to provide further evidence in this challenging field.

Level and clinical significance of serum bFGF in patients with ischemic cardiomyopathy

OBJECTIVE

To detect the level of serum basic fibroblast growth factor (bFGF) in patients with ischemic cardiomyopathy (ICM) and analyze its clinical significance.

METHODS

This is a prospective study. From June 2018 to June 2021, 244 patients diagnosed with ICM in the department of cardiology of Tianyou Hospital Affiliated to Wuhan University of Science and Technology and 244 healthy people who underwent physical examination in the physical examination center of our hospital during the same period were enrolled as the research subjects. Serum bFGF level was measured by ELISA kit, and the ICM patients were divided into a high bFGF group (180 cases) and a low bFGF group (64 cases) according to the cut-off value 56.83 obtained from X-tile software analysis, and the clinical data of the two groups were compared. In addition, according to the 12-month survival, the patients were grouped into a poor prognosis group (56 cases) and a good prognosis group (188 cases). Then, univariate and multivariate proportional hazards model (COX regression) analyses were applied to analyze the influencing factors of poor prognosis in ICM patients.

RESULTS

In the ICM group, there were more patients with hypertension and diabetes, and patients had higher levels of HbA1c, blood urea nitrogen, creatinine and uric acid, and lower levels of eGFR and bFGF than patients in the control group (P<0.05). The 12-month endpoint event rate in the low bFGF group was 54.69%, which was significantly higher than 11.67% in the high bFGF group (P<0.05). The left ventricular ejection fraction (LVEF) in the low bFGF group was significantly lower than that in the high bFGF group, and the bFGF group also had more patients with cardiac function grade IV (P<0.05). Multivariate COX regression analysis showed that age, diabetes, LVEF and low bFGF were independent influencing factors of poor prognosis in patients with ICM (P<0.05). After adjusting for age, diabetes and LVEF, patients with low bFGF had a higher risk of poor prognosis than those with high bFGF (HR=4.416, 95 CI%: 1.977-9.863, P<0.05).

CONCLUSION

The serum expression of bFGF in ICM patients is low, and the risk of poor prognosis is higher in patients with low bFGF, suggesting that serum bFGF level has a certain value in the prognosis evaluation of ICM patients.

A Systematic Review of miRNA and cfDNA as Potential Biomarkers for Liquid Biopsy in Myocarditis and Inflammatory Dilated Cardiomyopathy

Myocarditis and inflammatory dilated cardiomyopathy are cardiac diseases leading to heart failure. Liquid biopsy is a concept of replacing traditional biopsy with specialized blood tests. The study aim was to summarize and assess the usefulness of microRNAs and circulating free DNA as biomarkers of myocardial inflammation. For this systematic review, we searched Scopus, Embase, Web of Science, and PubMed. All studies measuring microRNAs in serum/plasma/cardiac tissue or circulating free DNA during myocarditis and non-ischemic dilated cardiomyopathy in humans in which healthy subjects or another cardiac disease served as a comparator were included. Data were extracted and miRNAs were screened and assessed using a scale created in-house. Then, highly graded miRNAs were assessed for usability as liquid biopsy biomarkers. Of 1185 records identified, 56 were eligible and 187 miRNAs were found. We did not identify any studies measuring circulating free DNA. In total, 24 of the screened miRNAs were included in the final assessment, 3 of which were selected as the best and 3 as potential candidates. We were not able to assess the risk of bias and the final inclusion decision was made by consensus. Serum levels of three miRNAs—miR-Chr8:96, miR-155, and miR-206—are the best candidates for myocardial inflammation liquid biopsy panel. Further studies are necessary to prove their role, specificity, and sensitivity.