LncRNA AK087124/miR-224-5p/PTEN axis modulates endothelial cell injury in atherosclerosis through apoptosis and AKT signaling pathway

Discovery of circulating miRNAs as biomarkers of chronic Chagas heart disease via a small RNA-Seq approach

Chagas disease affects approximately 7 million people worldwide in Latin America and is a neglected tropical disease. Twenty to thirty percent of chronically infected patients develop chronic Chagas cardiomyopathy decades after acute infection. Identifying biomarkers of Chagas disease progression is necessary to develop better therapeutic and preventive strategies. Circulating microRNAs are increasingly reliable biomarkers of disease and therapeutic targets. To identify new circulating microRNAs for Chagas disease, we performed exploratory small RNA sequencing from the plasma of patients and performed de novo miRNA prediction, identifying potential new microRNAs. The levels of the new microRNAs temporarily named miR-Contig-1519 and miR-Contig-3244 and microRNAs that are biomarkers for nonchagasic cardiomyopathies, such as miR-148a-3p and miR-224-5p, were validated by quantitative reverse transcription. We found a specific circulating microRNA signature defined by low miR-Contig-3244, miR-Contig-1519, and miR-148a-3 levels but high miR-224-5p levels for patients with chronic Chagas disease. Finally, we predicted in silico that these altered circulating microRNAs could affect the expression of target genes involved in different cellular pathways and biological processes, which we will explore in the future.

CircDLGAP4 induces autophagy and improves endothelial cell dysfunction in atherosclerosis by targeting PTPN4 with miR-134-5p

OBJECTIVE

Circular RNAs (circRNAs), a new subgroup of non-coding RNAs in the human transcriptome, are crucial in atherosclerosis (AS). Here, a newly identified circRNA circDLGAP4 was demonstrated to be downregulated in oxidized forms of low-density lipoprotein (ox-LDL)-induced HUVECs.

METHODS

This research adopted ox-LDL to stimulate human umbilical vein endothelial cells (HUVECs) to mimic AS in vitro. To further validate the protective action of circDLGAP4 in AS, a mouse model of AS was constructed with a high-fat diet. Functional assays evaluated circDLGAP4 role in AS in vitro and in vivo. Moreover, mechanism assays evaluated association of circDLGAP4/miR-134-5p/PTPN4.

RESULTS

CircDLGAP4 was induced to promote cell proliferative behavior and autophagy, inhibit apoptotic and inflammatory activities in ox-LDL-treated HUVECs, and attenuated endothelial barrier function. CircDLGAP4 regulated PTPN4 by directly targeting miR-134-5p. Meanwhile, inhibiting miR-134-5p reduced ox-LDL-induced cell dysfunction. Knockout of PTPN4 reversed circDLGAP4 overexpression or miR-134-5p downregulation in vitro. In addition, reducing circDLGAP4 or overexpressing miR-134-5p increased the red atherosclerotic plaque and lesion area of AS mice, reduced autophagy level, and promoted the release of inflammatory cytokines.

CONCLUSION

This study extends the role of circRNA in AS by inducing autophagy and improving endothelial dysfunction in AS via the circDLGAP4/miR-134-5p/PTPN4 axis.

The potential role and mechanism of circRNAs in foam cell formation

Atherosclerosis is a significant risk factor for coronary heart disease (CHD) and myocardial infarction (MI). Atherosclerosis develops during foam cell generation, which is caused by an imbalance in cholesterol uptake, esterification, and efflux. LOX-1, SR-A1, and CD36 all increased cholesterol uptake. ACAT1 and ACAT2 promote free cholesterol (FC) esterification to cholesteryl esters (CE). The hydrolysis of CE to FC was aided by nCEH. FC efflux was promoted by ABCA1, ABCG1, ADAM10, and apoA-I. SR-BI promotes not only cholesterol uptake but also FC efflux. Circular RNAs (circRNAs), which are single-stranded RNAs with a closed covalent circular structure, have emerged as promising biomarkers and therapeutic targets for atherosclerosis due to their highly tissue, cell, and disease state-specific expression profiles. Numerous studies have shown that circRNAs regulate foam cell formation, acting as miRNA sponges to influence atherosclerosis development by regulating the expression of SR-A1, CD36, ACAT2, ABCA1, ABCG1, ADAM10, apoA-I, SR-B1. Several circRNAs, including circ-Wdr91, circ 0004104, circRNA0044073, circRNA_0001805, circDENND1B, circRSF1, circ 0001445, and circRNA 102682, are potential biomarkers for atherosclerosis to better evaluate cardiovascular risk. It is difficult to deliver synthetic therapeutic circRNAs to the desired target tissues. Nanotechnology, such as GA-RM/GZ/PL, may be an important solution to this problem. In this review, we focus on the potential role and mechanism of circRNA/miRNA axis in foam cell formation in the hopes of discovering new targets for the diagnosis, prevention, and treatment of atherosclerosis.

Potential roles of endothelial cells-related non-coding RNAs in cardiovascular diseases

Endothelial dysfunction is identified by a conversion of the endothelium toward decreased vasodilation and prothrombic features and is known as a primary pathogenic incident in cardiovascular diseases. An insight based on particular and promising biomarkers of endothelial dysfunction may possess vital clinical significances. Currently, non-coding RNAs due to their participation in critical cardiovascular processes like initiation and progression have gained much attention as possible diagnostic as well as prognostic biomarkers in cardiovascular diseases. Emerging line of proof has demonstrated that abnormal expression of non-coding RNAs is nearly correlated with the pathogenesis of cardiovascular diseases. In the present review, we focus on the expression and functional effects of various kinds of non-coding RNAs in cardiovascular diseases and negotiate their possible clinical implications as diagnostic or prognostic biomarkers and curative targets.

LncRNA HCG11 Accelerates Atherosclerosis via Regulating the miR-224-3p/JAK1 Axis

Atherosclerosis (AS) is the typical cardiovascular disease, which is the main underlying inducement of cardiovascular diseases. Aberrant expression of long noncoding RNA HLA complex group 11 (HCG11) was engaged with atherosclerosis. The objective of the present research was to explore the role and the potential mechanism of HCG11 in AS. Human umbilical vein endothelial cells (HUVECs) were stimulated with oxidized low-density lipoprotein (ox-LDL) to induce the AS model in vitro. The cell viability was detected by MTT assay. Flow cytometry was performed to determine cell pyroptosis. Gene and protein levels were detected by qPCR or Western blot assay. The interaction between HCG11, miR-224-3p, and Janus kinase 1 (JAK1) was validated by dual-luciferase reporter assays. Ox-LDL treatment aggravated cell pyroptosis and inflammation in HUVECs. And the levels of HCG11 and JAK1 was enhanced in ox-LDL-induced HUVECs, while miR-224-3p expression was reduced. Additionally, knockdown of HCG11 or miR-224-3p overexpression reversed the ox-LDL-induced cell viability decline and the increase of cell pyroptosis and inflammation-related proteins, including gasdermin D N-terminal (GSDMD-N), Caspase-1, NOD-like receptor family pyrin domain-containing 3 (NLRP3), interleukin 18 (IL-18), and interleukin 1beta (IL-1β). Moreover, HCG11 could modulate the JAK1 expression via targeting miR-224-3p. The inhibitory effect of HCG11 silencing on cell pyroptosis and inflammation was reversed by miR-224-3p knockdown. Furthermore, overexpression of miR-224-3p could repress the ox-LDL-induced cell pyroptosis and inflammation via regulating JAK1 expression. Knockdown of HCG11 alleviated cell pyroptosis and inflammation induced by ox-LDL via targeting the miR-224-3p/JAK1 axis, indicating that HCG11 could be the latent target of diagnosis or treatment for AS.

Silencing of UCA1 attenuates the ox-LDL-induced injury of human umbilical vein endothelial cells via miR-873-5p/MAPK8 axis

LncRNA UCA1 plays a vital role in cardiovascular diseases. Endothelial cell dysfunction is a prerequisite for atherosclerosis (AS) development. However, the pathophysiological role of UCA1 in endothelial cell dysfunction induced by ox-LDL remains obscure. Here, we observed that UCA1 was upregulated in the sera of patients with AS and ox-LDL-treated endothelial cells. UCA1 knockdown dramatically reduced the cell apoptosis induced by ox-LDL and the production of pro-inflammatory cytokines and ROS in endothelial cells. Mechanistically, we found that UCA1 directly targeted miR-873-5p. UCA1 knockdown increased, while UCA1 overexpression decreased the expression of miR-873-5p. Further, we found that mitogen-activated protein kinase 8 (MAPK8) was a downstream target gene of miR-873-5p. MAPK8 overexpression or miR-873-5p knockdown reduced the enhancement of ox-LDL-induced cell apoptosis, oxidative stress, and pro-inflammatory cytokine production conferred by UCA1 knockdown. In conclusion, UCA1 can protect Human Umbilical Vein Endothelial Cells from ox-LDL-induced injury via the miR-873-5p/MAPK8 axis.

Long non-coding RNAs (lncRNAs) in hepatocellular carcinoma progression: Biological functions and new therapeutic targets

Liver is an important organ in body that performs vital functions such as detoxification. Liver is susceptible to development of cancers, and hepatocellular carcinoma (HCC) is among them. 75-85% of liver cancer cases are related to HCC. Therefore, much attention has been directed towards understanding factors mediating HCC progression. LncRNAs are epigenetic factors with more than 200 nucleotides in length located in both nucleus and cytoplasm and they are promising candidates in cancer therapy. Directing studies towards understanding function of lncRNAs in HCC is of importance. LncRNAs regulate cell cycle progression and growth of HCC cells, and they can also induce/inhibit apoptosis in tumor cells. LncRNAs affect invasion and metastasis in HCC mainly by epithelial-mesenchymal transition (EMT) mechanism. Revealing the association between lncRNAs and downstream signaling pathways in HCC is discussed in the current manuscript. Infectious diseases can affect lncRNA expression in mediating HCC development and then, altered expression level of lncRNA is associated with drug resistance and radio-resistance. Biomarker application of lncRNAs and their role in prognosis and diagnosis of HCC are also discussed to pave the way for treatment of HCC patients.