The prognostic potential of long noncoding RNA XIST in cardiovascular diseases: a review

There is a significant mortality rate associated with cardiovascular disease despite advances in treatment. long Non-coding RNAs (lncRNAs) play a critical role in many biological processes and their dysregulation is associated with a wide range of diseases in which their downstream pathways are disrupted. A lncRNA X-inactive specific transcript (XIST) is well known as a factor that regulates the physiological process of chromosome dosage compensation for females. According to recent studies, lncRNA XIST is involved in a variety of cellular processes, including apoptosis, proliferation, invasion, metastasis, oxidative stress and inflammation, through molecular networks with microRNAs and their downstream targets in neoplastic and non-neoplastic diseases. Because these cellular processes play a role in the pathogenesis of cardiovascular diseases, we aim to investigate the role that lncRNA XIST plays in this process. Additionally, we wish to determine whether it is a prognostic factor or a potential therapeutic target in these diseases.

The emerging role of pyroptosis-related inflammasome pathway in atherosclerosis

Atherosclerosis (AS), a chronic sterile inflammatory disorder, is one of the leading causes of mortality worldwide. The dysfunction and unnatural death of plaque cells, including vascular endothelial cells (VEC), macrophages, and vascular smooth muscle cells (VSMC), are crucial factors in the progression of AS. Pyroptosis was described as a form of cell death at least two decades ago. It is featured by plasma membrane swelling and rupture, cell lysis, and consequent robust release of cytosolic contents and pro-inflammatory mediators, including interleukin-1β (IL-1β), IL-18, and high mobility group box 1 (HMGB1). Pyroptosis of plaque cells is commonly observed in the initiation and development of AS, and the levels of pyroptosis-related proteins are positively correlated with plaque instability, indicating the crucial contribution of pyroptosis to atherogenesis. Furthermore, studies have also identified some candidate anti-atherogenic agents targeting plaque cell pyroptosis. Herein, we summarize the research progress in understating (1) the discovery and definition of pyroptosis; (2) the characterization and molecular mechanisms of pyroptosis; (3) the regulatory mechanisms of pyroptosis in VEC, macrophage, and VSMC, as well as their potential role in AS progression, aimed at providing therapeutic targets for the prevention and treatment of AS.

Knockdown of LINC00657 inhibits ox-LDL-induced endothelial cell injury by regulating miR-30c-5p/Wnt7b/β-catenin

Long noncoding RNAs (lncRNAs) play pivotal roles in the pathogenesis, development, and treatment of atherosclerosis (AS). The endothelial cell injury is a feature of AS. However, the role and mechanism of lncRNA LINC00657 in oxidized low-density lipoprotein (ox-LDL)-induced endothelial cell injury remain unclear. The serum samples were collected from 32 AS patients and normal volunteers. Ox-LDL-treated human umbilical vein endothelial cells (HUVEC) were used for the experiments in vitro. The levels of LINC00657, microRNA (miR)-30c-5p and Wnt family member 7B (Wnt7b) were measured by quantitative real-time polymerase chain reaction or western blot. The expression levels of proteins in Wnt7b/β-catenin pathway or endothelial-mesenchymal transition (EndMT) were detected by western blot. The secretion of inflammatory cytokine was examined by enzyme linked immunosorbent assay (ELISA). Cell viability and apoptosis were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide, flow cytometry, and western blot. The target association of miR-30c-5p and LINC00657/Wnt7b was analyzed via dual-luciferase reporter assay and RNA pull-down assay. LINC00657 expression was increased in AS serum and ox-LDL-treated HUVEC cells. LINC00657 knockdown suppressed ox-LDL-induced Wnt7b/β-catenin activation, EndMT, inflammatory response, and apoptosis in HUVEC cells. MiR-30c-5p was bound to LINC00657 and it knockdown reversed the role of LINC00657 inhibition in ox-LDL-induced HUVEC cell injury. MiR-30c-5p targeted Wnt7b to inhibit ox-LDL-induced Wnt7b/β-catenin activation, EndMT, inflammatory response, and apoptosis in HUVEC cells. Silence of LINC00657 repressed ox-LDL-induced injury via inhibiting EndMT, inflammatory response, and apoptosis in HUVEC cells by regulating miR-30c-5p/Wnt7b/β-catenin, indicating a potential target for treatment of AS.

Significant changes in synovial fluid microRNAs after high tibial osteotomy in medial compartmental knee osteoarthritis: Identification of potential prognostic biomarkers

High tibial osteotomy (HTO) is a well-established treatment for medial compartmental knee osteoarthritis. Several microRNAs (miRNAs) are involved in osteoarthritis progression and are useful as osteoarthritis-related biomarkers. In this prospective study, we investigated differentially expressed microRNAs in the synovial fluid (SF) before and after HTO in patients with medial compartmental knee osteoarthritis to identify microRNAs that can be used as prognostic biomarkers. We used miRNA-PCR arrays to screen for miRNAs in SF samples obtained preoperatively and 6 months postoperatively from 6 patients with medial compartmental knee osteoarthritis who were treated with medial open wedge HTO. Differentially expressed miRNAs identified in the profiling stage were validated by real-time quantitative PCR in 22 other patients who had also been treated with HTO. All patients radiographically corresponded to Kellgren-Lawrence grade II or III with medial compartmental osteoarthritis. These patients were clinically assessed using a visual analogue scale and Western Ontario McMaster Universities scores. Mechanical axis changes were measured on standing anteroposterior radiographs of the lower limbs assessed preoperatively and at 6 months postoperatively. Among 84 miRNAs known to be involved in the inflammatory process, 14 were expressed in all SF specimens and 3 (miR-30a-5p, miR-29a-3p, and miR-30c-5p) were differentially expressed in the profiling stage. These 3 miRNAs, as well as 4 other miRNAs (miR-378a-5p, miR-140-3p, miR-23a-3p, miR-27b-3p), are related to osteoarthritis progression. These results were validated in the SF from 22 patients. Clinical and radiological outcomes improved after HTO in all patients, and only 2 miRNAs (miR-30c-5p and miR-23a-3p) were significantly differentially expressed between preoperative and postoperative 6-month SF samples (p = 0.006 and 0.007, respectively). Of these two miRNAs, miR-30c-5p correlated with postoperative pain relief. This study provides potential prognostic miRNAs after HTO and further investigations should be considered to determine clinical implications of these miRNAs.

Genome-wide microRNA screening reveals miR-582-5p as a mesenchymal stem cell-specific microRNA in subchondral bone of the human knee joint

Emerging evidence suggests that microRNAs (miRNAs) may be pathologically involved in osteoarthritis (OA). Subchondral bone (SCB) sclerosis is accounted for the knee osteoarthritis (KOA) development and progression. In this study, we aimed to screen the miRNA biomarkers of KOA and investigated whether these miRNAs regulate the differentiation potential of mesenchymal stem cells (MSCs) and thus contributing to SCB. We identified 48 miRNAs in the blood samples in KOA patients (n = 5) through microarray expression profiling detection. After validation with larger sample number, we confirmed hsa-miR-582-5p and hsa-miR-424-5p were associated with the pathology of SCB sclerosis. Target genes prediction and pathway analysis were implemented with online databases, indicating these two candidate miRNAs were closely related to the pathways of pluripotency of stem cells and pathology of OA. Surprisingly, mmu-miR-582-5p (homology of hsa-miR-582-5p) was downregulated in osteogenic differentiation and upregulated in adipogenic differentiation of mesenchymal progenitor C3H10T1/2 cells, whereas mmu-mir-322-5p (homology of hsa-miR-424-5p) showed no change through the in vitro study. Supplementing mmu-miR-582-5p mimics blocked osteogenic and induced adipogenic differentiation of C3H10T1/2 cells, whereas silencing of the endogenous mmu-miR-582-5p enhanced osteogenic and repressed adipogenic differentiation. Further mechanism studies showed that mmu-miR-582-5p was directly targeted to Runx2. Mutation of putative mmu-miR-582-5p binding sites in Runx2 3' untranslated region (3'UTR) could abolish the response of the 3'UTR-luciferase construct to mmu-miR-582-5p supplementation. Generally speaking, our data suggest that miR-582-5p is an important biomarker of KOA and is able to regulate osteogenic and adipogenic differentiation of MSCs via targeting Runx2. The study also suggests that miR-582-5p may play a crucial role in SCB sclerosis of human KOA.

MicroRNA-30c-5p inhibits NLRP3 inflammasome-mediated endothelial cell pyroptosis through FOXO3 down-regulation in atherosclerosis

Atherosclerosis is a chronic inflammatory disease involved in endothelial dysfunction. Pyroptosis is a pro-inflammatory form of cell death and plays pivotal roles in atherosclerosis. MicroRNAs (miRNAs) are implicated in atherosclerosis, however the mechanisms that underlie miR-30c-5p is required for endothelial cell pyroptosis remain elusive. In the present study, we probed the interaction of miR-30c-5p with forkhead box O3 (FOXO3) and investigated the effect of miR-30c-5p and FOXO3 on NLRP3 inflammasome and endothelial cell pyroptosis. Introduction of oxidized low density lipoprotein (ox-LDL) dose-dependently increased lactate dehydrogenase (LDH) release as well as pyroptosis in human aortic endothelial cells (HAECs). On the basis of ox-LDL treatment, we found the expression of miR-30c-5p was impaired and enrichment of miR-30c-5p protected HAECs from ox-LDL-induced pyroptosis. Moreover, addition of miR-30c-5p inhibited ox-LDL-activated NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, which was associated with HEACs pyroptosis. Nevertheless, miR-30c-5p failed to show efficacy of Toll-like receptor (TLR) signaling of NLRP3 inflammasome activation. Intriguingly, FOXO3 was suggested to be targeted by miR-30c-5p and addition of miR-30c-5p blocked FOXO3 expression, whereas miR-30c-5p depletion showed opposite effects. Furthermore, silencing of FOXO3 inhibited NLRP3-mediated pyroptosis and reversed anti-miR-30c-5p-induced activation of NLRP3 inflammasome and pyroptosis in HEACs with ox-LDL treatment. Our finding suggested that miR-30c-5p might play essential role in NLRP3 inflammasome-modulated cell pyroptosis by targeting FOXO3 in HAECs, providing a novel therapeutic avenue for atherosclerosis treatment.