miR-223-3p inhibits the progression of atherosclerosis via down-regulating the activation of MEK1/ERK1/2 in macrophages

Cell Division Control Protein 42 Facilitates Diabetic Retinopathy Progression by Activating the MEK/ERK Pathway

Cell division control protein 42 (CDC42) modulates insulin secretion and angiogenesis to participate in the pathology of diabetic complications and retinal vascular-associated diseases. This study intended to explore the role of CDC42 in the progression of diabetic retinopathy, and the underlying mechanism. Human retinal microvascular endothelial cells (hRMECs) were cultured in 5.5 mM glucose (normal glucose) or 25 mM glucose (high glucose; HG) medium, respectively. CDC42 overexpression plasmid and small interference RNA (oe-CDC42 and si-CDC42) or corresponding negative controls (oe-NC and si-NC) were transfected into hRMECs under HG. Then, platelet-activating factor C-16 (C16-PAF) (MEK/ERK pathway activator) was added to si-CDC42 or si-NC transfected hRMECs under HG. Our study showed that HG increased CDC42 mRNA and protein, cell viability, invasive cell count, branch points, and tube length but reduced cell apoptosis in hRMECs. CDC42 upregulation enhanced cell viability, invasive cell count, branch points, tube length, p-MEK, and p-ERK, but attenuated cell apoptosis. Downregulation of CDC42 exhibited opposite trends. In addition, C16-PAF also increased cell viability, invasive cell count, branch points, and tube length, p-MEK, and p-ERK, but retarded cell apoptosis. Notably, C16-PAF diminished the effect of CDC42 downregulation on the above-mentioned functions in hRMECs under HG. Conclusively, CDC42 promotes HG-induced hRMEC viability and invasion, as well as angiogenesis, but inhibits apoptosis by activating the MEK/ERK pathway, which may be responsible for the progression of diabetic retinopathy.

Exosome miR-223-3p in the bone marrow-derived mesenchymal stem cells alleviates the inflammation and airway remodeling through NLRP3-induced ASC/Caspase-1/GSDMD signaling pathway

Asthma is one of the most common chronic respiratory diseases in the world. Exploration and understanding of the pathogenesis of epithelial-mesenchymal transition in airway epithelial cells, and the development of new molecular drugs targeted at airway inflammation and remodeling have become the key and hot points in the prevention and treatment of asthma. Emerging evidence has proven that miRNAs are strongly associated with numerous chronic respiratory diseases including asthma, but the involved molecular mechanisms have not been revealed. In the present study, we successfully isolated exosomes from BMMSCs and found that the derived exosomes could improve airway inflammation and remodeling in ovalbumin-induced asthma rats. Furthermore, we found that the highly expressed miR-223-3p in exosomes might play a key pivotal role in the protective effects on airway remodeling and asthma by regulating the NLRP3-induced ASC/Caspase-1/GSDMD signaling pathway. These results provided a promising molecule candidate and target for the therapy of asthma.

miR-223: a key regulator of pulmonary inflammation

Small noncoding RNAs, known as microRNAs (miRNAs), are vital for the regulation of diverse biological processes. miR-223, an evolutionarily conserved anti-inflammatory miRNA expressed in cells of the myeloid lineage, has been implicated in the regulation of monocyte-macrophage differentiation, proinflammatory responses, and the recruitment of neutrophils. The biological functions of this gene are regulated by its expression levels in cells or tissues. In this review, we first outline the regulatory role of miR-223 in granulocytes, macrophages, endothelial cells, epithelial cells and dendritic cells (DCs). Then, we summarize the possible role of miR-223 in chronic obstructive pulmonary disease (COPD), acute lung injury (ALI), coronavirus disease 2019 (COVID-19) and other pulmonary inflammatory diseases to better understand the molecular regulatory networks in pulmonary inflammatory diseases.

Inflammatory microRNAs in cardiovascular pathology: another brick in the wall

The regulatory role of microRNAs (miRNAs) is mainly mediated by their effect on protein expression and is recognized in a multitude of pathophysiological processes. In recent decades, accumulating evidence has interest in these factors as modulatory elements of cardiovascular pathophysiology. Furthermore, additional biological processes have been identified as new components of cardiovascular disease etiology. In particular, inflammation is now considered an important cardiovascular risk factor. Thus, in the present review, we will focus on the role of a subset of miRNAs called inflamma-miRs that may regulate inflammatory status in the development of cardiovascular pathology. According to published data, the most representative candidates that play functional roles in thromboinflammation are miR-21, miR-33, miR-34a, miR-146a, miR-155, and miR-223. We will describe the functions of these miRNAs in several cardiovascular pathologies in depth, with specific emphasis on the molecular mechanisms related to atherogenesis. We will also discuss the latest findings on the role of miRNAs as regulators of neutrophil extracellular traps and their impact on cardiovascular diseases. Overall, the data suggest that the use of miRNAs as therapeutic tools or biomarkers may improve the diagnosis or prognosis of adverse cardiovascular events in inflammatory diseases. Thus, targeting or increasing the levels of adequate inflamma-miRs at different stages of disease could help mitigate or avoid the development of cardiovascular morbidities.

Regulation of HIF-1 by MicroRNAs in Various Cardiovascular Diseases

Today, we see an increase in death due to cardiovascular diseases all over the world, which has a lot to do with the regulation of oxygen homeostasis. Also, hypoxia-inducing factor 1 (HIF-1) is considered a vital factor in hypoxia and its physiological and pathological changes. HIF- 1 is involved in cellular activities, including proliferation, differentiation, and cell death in endothelial cells (ECs) and cardiomyocytes. Similar to HIF-1α, which acts as a protective element against various diseases in the cardiovascular system, the protective role of microRNAs (miRNAs) has also been proved using animal models. The number of miRNAs identified in the regulation of gene expression responsive to hypoxia and the importance of investigating the involvement of the non-coding genome in cardiovascular diseases is increasing, which shows the issue's importance. In this study, the molecular regulation of HIF-1 by miRNAs is considered to improve therapeutic approaches in clinical diagnoses of cardiovascular diseases.

Differential expression of exosomal microRNAs in fresh and senescent apheresis platelet concentrates

Patients have a high risk of suffering adverse reactions after receiving platelet products stored for 5 days. Bioactive exosomes in platelet products can be accumulated during storage, which is associated with adverse reactions. MicroRNAs are one of the critical cargoes in exosomes, which participate in cell differentiation, metabolism, and immunomodulation. This study intends to elucidate and analyze the differential expression of exosomal microRNAs in apheresis platelet concentrates during storage and predict the potential functions of target genes. Apheresis platelet concentrates were used to isolate exosomes by ultracentrifugation. Exosomes were phenotyped by western blot, transmission electron microscopy, and nano flow cytometry. The differential expression of the exosomal microRNAs was obtained by a microarray test using four bags of apheresis platelets stored for 5 days compared with 1 day. The differentially expressed microRNAs between the two time points were identified, and their target genes were analyzed by miRWalk and miRDB. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to predict the target genes' functions. Fifteen bags of apheresis platelet concentrates stored for 1 day and 5 days were used to verify the microarray results by quantitative reverse transcription-polymerase chain reactions (qRT-PCR). There were 134 microRNAs in total expressed differently in the two groups (day 1 and day 5), with 57 microRNAs up-regulated and 77 down-regulated (|fold change| > 2.0 and P < .05). Thirteen up-regulated microRNAs (hsa-miR-22-3p, hsa-miR-223-3p, hsa-miR-21-5p, hsa-miR-23a-3p, hsa-miR-320b, hsa-let-7a-5p, hsa-miR-25-3p, hsa-miR-126-3p, hsa-miR-320c, hsa-miR-342-3p, hsa-miR-320d, hsa-miR-328-3p, and hsa-miR-320e) detected in all samples were selected to validate the results. The qRT-PCR results showed that five (hsa-miR-22-3p, hsa-miR-223-3p, hsa-miR-21-5p, hsa-miR-23a-3p, and hsa-miR-320b) of them were increased more than 10-fold (P < .001); four (hsa-let-7a-5p, hsa-miR-25-3p, hsa-miR-126-3p, hsa-miR-320c) more than five-fold (P < .001); two (hsa-miR-342-3p and hsa-miR-320d) more than two-fold (P < .05); and two (hsa-miR-328-3p and hsa-miR-320e) more than two-fold (P > .05). Specifically, hsa-miR-22-3p increased 14.6-fold; hsa-miR-223-3p increased 13.0-fold; and hsa-miR-21-5p increased 12.0-fold. Based on bioinformatics functional analysis, target genes of top nine microRNAs (hsa-miR-22-3p, hsa-miR-223-3p, hsa-miR-21-5p, hsa-miR-23a-3p, hsa-miR-320b, hsa-let-7a-5p, hsa-miR-25-3p, hsa-miR-126-3p, and hsa-miR-320c) were annotated with positive regulation of cell proliferation and nervous system development, and mainly enriched in regulating pluripotency of stem cells signaling pathway, prolactin signaling pathway, and FoxO signaling pathway, etc. The prolactin, FoxO, ErbB, and TNF signaling pathway were relevant to immunomodulation. In particular, hsa-miR-22-3p expression was the most different during storage, with a fold change of 14.6, which might be a key mediator.

miR-99a-5p: A Potential New Therapy for Atherosclerosis by Targeting mTOR and Then Inhibiting NLRP3 Inflammasome Activation and Promoting Macrophage Autophagy

Objective

MicroRNAs have been revealed to be involved in the development of atherosclerosis. The present study is aimed at exploring the potential of miR-99a-5p as a therapy for atherosclerosis. We suspected that miR-99a-5p might inhibit NLRP3 inflammasome activation and promote macrophage autophagy via constraining mTOR, therefore, alleviating atherosclerosis.

Methods

The cell viability in ox-LDL-induced THP-1 macrophages was assessed by CCK-8 assay. Bioinformatic analysis was used to predict the target genes of miR-99a-5p. The binding between miR-99a-5p and mTOR was confirmed by luciferase reporter assay. In vivo, a high-fat-diet-induced atherosclerosis model was established in apolipoprotein E knockout mice. Hematoxylin-eosin, oil red O, and Sirius red staining were performed for the determination of atherosclerotic lesions. MTOR and associated protein levels were detected by Western blot analysis.

Results

miR-99a-5p inhibited NLRP3 inflammasome activation and promoted macrophage autophagy by targeting mTOR. Enforced miR-99a-5p significantly reduced the levels of inflammasome complex and inflammatory cytokines. Furthermore, miR-99a-5p overexpression inhibited the expression of mTOR, whereas mTOR overexpression reversed the trend of the above behaviors. In vivo, the specific overexpression of miR-99a-5p significantly reduced atherosclerotic lesions, accompanied by a significant downregulation of autophagy marker CD68 protein expression.

Conclusion

We demonstrated for the first time that miR-99a-5p may be considered a therapy for atherosclerosis. The present study has revealed that miR-99a-5p might inhibit NLRP3 inflammasome activation and promote macrophage autophagy by targeting mTOR, therefore, alleviating atherosclerosis.

Effect of Thrombin on the Metabolism and Function of Murine Macrophages

Macrophages are plastic and heterogeneous immune cells that adapt pro- or anti-inflammatory phenotypes upon exposure to different stimuli. Even though there has been evidence supporting a crosstalk between coagulation and innate immunity, the way in which protein components of the hemostasis pathway influence macrophages remains unclear. We investigated the effect of thrombin on macrophage polarization. On the basis of gene expression and cytokine secretion, our results suggest that polarization with thrombin induces an anti-inflammatory, M2-like phenotype. In functional studies, thrombin polarization promoted oxLDL phagocytosis by macrophages, and conditioned medium from the same cells increased endothelial cell proliferation. There were, however, clear differences between the classical M2a polarization and the effects of thrombin on gene expression. Finally, the deletion and inactivation of secreted modular Ca²⁺-binding protein 1 (SMOC1) attenuated phagocytosis by thrombin-stimulated macrophages, a phenomenon revered by the addition of recombinant SMOC1. Manipulation of SMOC1 levels also had a pronounced impact on the expression of TGF-β-signaling-related genes. Taken together, our results show that thrombin induces an anti-inflammatory macrophage phenotype with similarities as well as differences to the classical alternatively activated M2 polarization states, highlighting the importance of tissue levels of SMOC1 in modifying thrombin-induced macrophage polarization.

The Prospective Application of Melatonin in Treating Epigenetic Dysfunctional Diseases

In the past, different human disorders were described by scientists from the perspective of either environmental factors or just by genetically related mechanisms. The rise in epigenetic studies and its modifications, i.e., heritable alterations in gene expression without changes in DNA sequences, have now been confirmed in diseases. Modifications namely, DNA methylation, posttranslational histone modifications, and non-coding RNAs have led to a better understanding of the coaction between epigenetic alterations and human pathologies. Melatonin is a widely-produced indoleamine regulator molecule that influences numerous biological functions within many cell types. Concerning its broad spectrum of actions, melatonin should be investigated much more for its contribution to the upstream and downstream mechanistic regulation of epigenetic modifications in diseases. It is, therefore, necessary to fill the existing gaps concerning corresponding processes associated with melatonin with the physiological abnormalities brought by epigenetic modifications. This review outlines the findings on melatonin’s action on epigenetic regulation in human diseases including neurodegenerative diseases, diabetes, cancer, and cardiovascular diseases. It summarizes the ability of melatonin to act on molecules such as proteins and RNAs which affect the development and progression of diseases.