The Long Noncoding RNA RP11-728F11.4 Promotes Atherosclerosis.

OBJECTIVE: Noncoding RNAs are emerging as important players in gene regulation and cardiovascular diseases. Their roles in the pathogenesis of atherosclerosis are not fully understood. The purpose of this study was to determine the role played by a previously uncharacterized long noncoding RNA, RP11-728F11.4, in the development of atherosclerosis and the mechanisms by which it acts. Approach and Results: Expression microarray analysis revealed that atherosclerotic plaques had increased expression of RP11-728F11.4 as well as the cognate gene FXYD6 (FXYD domain containing ion transport regulator 6), which encodes a modulator of Na+/K+-ATPase. In vitro experiments showed that RP11-728F11.4 interacted with the RNA-binding protein EWSR1 (Ewings sarcoma RNA binding protein-1) and upregulated FXYD6 expression. Lentivirus-induced overexpression of RP11-728F11.4 in cultured monocytes-derived macrophages resulted in higher Na+/K+-ATPase activity, intracellular cholesterol accumulation, and increased proinflammatory cytokine production. The effects of RP11-728F11.4 were enhanced by siRNA-mediated knockdown of EWSR1 and reduced by downregulation of FXYD domain containing ion transport regulator 6. In vivo experiments in apoE knockout mice fed a Western diet demonstrated that RP11-728F11.4 increased proinflammatory cytokine production and augmented atherosclerotic lesions. CONCLUSIONS: RP11-728F11.4 promotes atherosclerosis, with an influence on cholesterol homeostasis and proinflammatory molecule production, thus representing a potential therapeutic target. Graphic Abstract: A graphic abstract is available for this article.

Overview of noncoding RNAs involved in the osteogenic differentiation of periodontal ligament stem cells.

Periodontal diseases are infectious diseases that are characterized by progressive damage to dental support tissue. The major goal of periodontal therapy is to regenerate the periodontium destroyed by periodontal diseases. Human periodontal ligament (PDL) tissue possesses periodontal regenerative properties, and periodontal ligament stem cells (PDLSCs) with the capacity for osteogenic differentiation show strong potential in clinical application for periodontium repair and regeneration. Noncoding RNAs (ncRNAs), which include a substantial portion of poly-A tail mature RNAs, are considered "transcriptional noise." Recent studies show that ncRNAs play a major role in PDLSC differentiation; therefore, exploring how ncRNAs participate in the osteogenic differentiation of PDLSCs may help to elucidate the underlying mechanism of the osteogenic differentiation of PDLSCs and further shed light on the potential of stem cell transplantation for periodontium regeneration. In this review paper, we discuss the history of PDLSC research and highlight the regulatory mechanism of ncRNAs in the osteogenic differentiation of PDLSCs.

Long noncoding RNA NEXN-AS1 mitigates atherosclerosis by regulating the actin-binding protein NEXN.

Noncoding RNAs are emerging as important players in gene regulation and disease pathogeneses. Here, we show that a previously uncharacterized long noncoding RNA, nexilin F-actin binding protein antisense RNA 1 (NEXN-AS1), modulates the expression of the actin-binding protein NEXN and that NEXN exerts a protective role against atherosclerosis. An expression microarray analysis showed that the expression of both NEXN-AS1 and NEXN was reduced in human atherosclerotic plaques. In vitro experiments revealed that NEXN-AS1 interacted with the chromatin remodeler BAZ1A and the 5' flanking region of the NEXN gene and that it also upregulated NEXN expression. Augmentation of NEXN-AS1 expression inhibited TLR4 oligomerization and NF-κB activity, downregulated the expression of adhesion molecules and inflammatory cytokines by endothelial cells, and suppressed monocyte adhesion to endothelial cells. These inhibitory effects of NEXN-AS1 were abolished by knockdown of NEXN. In vivo experiments using ApoE-knockout mice fed a Western high-fat diet demonstrated that NEXN deficiency promoted atherosclerosis and increased macrophage abundance in atherosclerotic lesions, with heightened expression of adhesion molecules and inflammatory cytokines, whereas augmented NEXN expression deterred atherosclerosis. Patients with coronary artery disease were found to have lower blood NEXN levels than healthy individuals. These results indicate that NEXN-AS1 and NEXN represent potential therapeutic targets in atherosclerosis-related diseases.

Periostin is essential for periodontal ligament remodeling during orthodontic treatment.

Orthodontic tooth movement is a process stimulated and maintained by external tensile stress; periodontal ligament remodeling serves an important role during this process. However, the function and underlying mechanism of periostin (PN) during orthodontic periodontal ligament remodeling remain unclear. The present study established in vitro and in vivo models of orthodontic treatment to investigate the expression levels of PN under conditions of external tensile stress load. These results indicated that tensile stress load increased the expression levels of PN in mouse peridontal ligaments and human periodontal ligament cells (hPDLCs), during orthodontic tooth movement. Furthermore, the present study demonstrated that the expression levels of PN were regulated by transforming grown factor ß, and that PN promotes type I collagen and α­smooth muscle actin expression levels in hPDLCs. Therefore, PN may be essential for periodontal ligament remodeling during orthodontic treatment, and therefore may represent a potential therapeutic target.