Statin-induced microRNAome alterations modulating inflammation pathways of peripheral blood mononuclear cells in patients with hypercholesterolemia

Characterization of Systemic and Culprit-Coronary Artery miR-483-5p Expression in Chronic CAD and Acute Myocardial Infarction Male Patients

Coronary artery disease (CAD) is the leading cause of mortality worldwide. In chronic and myocardial infarction (MI) states, aberrant levels of circulating microRNAs compromise gene expression and pathophysiology. We aimed to compare microRNA expression in chronic-CAD and acute-MI male patients in peripheral blood vasculature versus coronary arteries proximal to a culprit area. Blood from chronic-CAD, acute-MI with/out ST segment elevation (STEMI/NSTEMI, respectively), and control patients lacking previous CAD or having patent coronary arteries was collected during coronary catheterization from peripheral arteries and from proximal culprit coronary arteries aimed for the interventions. Random coronary arterial blood was collected from controls; RNA extraction, miRNA library preparation and Next Generation Sequencing followed. High concentrations of microRNA-483-5p (miR-483-5p) were noted as 'coronary arterial gradient' in culprit acute-MI versus chronic-CAD (p = 0.035) which were similar to controls versus chronic-CAD (p < 0.001). Meanwhile, peripheral miR-483-5p was downregulated in acute-MI and chronic-CAD, compared with controls (1.1 ± 2.2 vs. 2.6 ± 3.3, respectively, p < 0.005). A receiver operating characteristic curve analysis for miR483-5p association with chronic CAD demonstrated an area under the curve of 0.722 (p < 0.001) with 79% sensitivity and 70% specificity. Using in silico gene analysis, we detected miR-483-5p cardiac gene targets, responsible for inflammation (PLA2G5), oxidative stress (NUDT8, GRK2), apoptosis (DNAAF10), fibrosis (IQSEC2, ZMYM6, MYOM2), angiogenesis (HGSNAT, TIMP2) and wound healing (ADAMTS2). High miR-483-5p 'coronary arterial gradient' in acute-MI, unnoticed in chronic-CAD, suggests important local mechanisms for miR483-5p in CAD in response to local myocardial ischemia. MiR-483-5p may have an important role as a gene modulator for pathologic and tissue repair states, is a suggestive biomarker, and is a potential therapeutic target for acute and chronic cardiovascular disease.

Peripheral Monocyte Percentage as a Potential Indicator of Prognosis in Patients with Chronic Subdural Hematoma Receiving Conservative Therapy

BACKGROUND

Studies have confirmed active and abnormal inflammation in the hematoma cavity of chronic subdural hematoma (CSDH). However, a relationship between the peripheral blood status and the prognosis of CSDH patients has not been demonstrated.

METHODS

We retrospectively analyzed 245 CSDH patients who received conservative therapy (67 under close follow-up observation, 103 treated with atorvastatin, and 75 treated with atorvastatin combined with dexamethasone) from 2014 to 2021 to evaluate the role of major inflammation-associated cells in the prognostic assessment of patients. Univariate and multivariate analyses were performed to assess the potential factors that could indicate the prognosis among the 103 patients who underwent observation only or atorvastatin therapy. Changes in peripheral blood inflammation-associated cells at different time points were compared between patients with good and poor outcomes. Furthermore, the changes in inflammatory cells in 75 patients who received atorvastatin combined with dexamethasone were analyzed.

RESULTS

The monocyte percentage was the only independent influencing factor in subsequent follow-up assessments. Patients with good outcomes had obviously lower circulating monocyte percentages in their peripheral blood counts throughout the treatment period. The monocyte percentage was also significantly decreased in the patients who responded well to atorvastatin combined with dexamethasone. The peripheral monocyte percentage was significantly higher in patients who transitioned to surgery because of a poor response to pharmacotherapy.

CONCLUSIONS

The peripheral monocyte percentage may be a convenient and effective indicator for predicting the outcome of CSDH for patients receiving conservative treatment. A higher percentage of monocytes could be a risk factor for a poor response.

Decoding microRNA drivers in Atherosclerosis

An estimated 97% of the human genome consists of non-protein-coding sequences. As our understanding of genome regulation improves, this has led to the characterization of a diverse array of non-coding RNAs (ncRNA). Among these, micro-RNAs (miRNAs) belong to the short ncRNA class (22–25 nucleotides in length), with approximately 2500 miRNA genes encoded within the human genome. From a therapeutic perspective, there is interest in exploiting miRNA as biomarkers of disease progression and response to treatments, as well as miRNA mimics/repressors as novel medicines. miRNA have emerged as an important class of RNA master regulators with important roles identified in the pathogenesis of atherosclerotic cardiovascular disease. Atherosclerosis is characterized by a chronic inflammatory build-up, driven largely by low-density lipoprotein cholesterol accumulation within the artery wall and vascular injury, including endothelial dysfunction, leukocyte recruitment and vascular remodelling. Conventional therapy focuses on lifestyle interventions, blood pressure-lowering medications, high-intensity statin therapy and antiplatelet agents. However, a significant proportion of patients remain at increased risk of cardiovascular disease. This continued cardiovascular risk is referred to as residual risk. Hence, a new drug class targeting atherosclerosis could synergise with existing therapies to optimise outcomes. Here, we review our current understanding of the role of ncRNA, with a focus on miRNA, in the development and progression of atherosclerosis, highlighting novel biological mechanisms and therapeutic avenues.

MicroRNA-20a-5p Downregulation by Atorvastatin: A Potential Mechanism Involved in Lipid-Lowering Therapy

The treatment of hypercholesterolemia is mainly based on statins. However, the response to pharmacological therapy shows high inter-individual variability, resulting in variable effects in both lipid lowering and risk reduction. Thus, a better understanding of the lipid-lowering mechanisms and response variability at the molecular level is required. Previously, we demonstrated a deregulation of the microRNA expression profile in HepG2 cells treated for 24 h with atorvastatin, using a microarray platform. In the present study, we evaluated the expression of hsa-miR-17-5p, hsa-miR-20a-5p and hsa-miR-106a-5p in hypercholesterolemic patients before and after atorvastatin treatment and in HepG2 cells treated for 24 h with atorvastatin The miRNA hsa-mir-20a-5p was repressed after atorvastatin treatment in hypercholesteremic subjects and in HepG2 cells in culture. Repression of hsa-mir-20a-5p increased LDLR gene and protein expression in HepG2 cells, while hsa-mir-20a-5p overexpression reduced LDLR gene and protein expression.

Epigenetics and microRNAs in cardiovascular diseases

Cardiovascular diseases are among the leading causes of mortality worldwide. Besides environmental and genetic changes, these disorders can be influenced by processes which do not affect DNA sequence yet still play an important role in gene expression and which can be inherited. These so-called 'epigenetic' changes include DNA methylation, histone modifications, and ATP-dependent chromatin remodeling enzymes, which influence chromatin remodeling and gene expression. Next to these, microRNAs are non-coding RNA molecules that silence genes post-transcriptionally. Both epigenetic factors and microRNAs are known to influence cardiac development and homeostasis, in an individual fashion but also in a complex regulatory network. In this review, we will discuss how epigenetic factors and microRNAs interact with each other and how together they can influence cardiovascular diseases.