Prevalence and associated factors of health anxiety in patients with temporomandibular disorders.

OBJECTIVES: To investigate the prevalence and associated factors of health anxiety (HA) in patients with Temporomandibular Disorders (TMDs) using the 8-item Whiteley Index (WI-8) scale. MATERIALS AND METHODS: Three hundred and twenty-nine TMDs patients completed the Visual Analog Scale (VAS), WI-8, Jaw Functional Limitation Scale-8 (JFLS-8), Patient Health Questionnaire-9 (PHQ-9), and Generalized Anxiety Disorder-7 (GAD-7) scales. Clinical examinations were conducted following the Diagnostic Criteria for TMDs Axis I. RESULTS: The prevalence of HA among TMDs patients was 18.54%. Patients with HA had higher scores of VAS-current (p = 0.026), VAS-maximum (p = 0.024), VAS-average (p = 0.030), JFLS-8 (p < 0.001), GAD-7 (p < 0.001) and PHQ-9 (p < 0.001), lower maximum mouth opening (p = 0.016), lower proportion of structure-related TMDs (p = 0.028), and higher proportion of pain-related TMDs (p < 0.001) compared to those without HA. The correlation coefficient was 0.61 (p < 0.001) between WI-8 and GAD-7 and 0.64 (p < 0.001) between WI-8 and PHQ-9. CONCLUSION: Approximately one-fifth of patients with TMDs experienced HA. HA was associated with pain perception, functional limitations, depressive, and anxiety symptoms in individuals with TMDs. HA may contribute to heightened subjective pain experiences rather than structural changes in the TMJ.

Orthodontic camouflage treatment for a patient with bilateral cleft lip and palate, bilateral crossbite, and microdontic maxillary lateral incisors.

Cleft lip and palate is a congenital craniofacial anomaly that affects the lip and oral cavity. The management and orthodontic treatment of this anomaly is important but challenging. This article reports the successful treatment of a patient with bilateral cleft lip and palate, Class III malocclusion, bilateral crossbite, crowding and microdontic maxillary lateral incisors. One mandible incisor was extracted, and three miniscrew anchorages were utilized to distalize the maxillary left dental arch and retract the mandibular arch. After treatment, ideal occlusion and a better profile were established, and long-term stability was confirmed by a 4-year follow-up. This article represents a successful attempt of orthodontic camouflage treatment of severe dentofacial discrepancy, as an important part of the series treatment of cleft lip and palate, to provide some insight into the clinical field.

BzATP reverses ferroptosis-induced gut microbiota disorders in collagen-induced arthritis mice.

Recent studies suggested that altered gut microbiota may be related to the pathogenesis of rheumatoid arthritis (RA), albeit the exact mechanisms are unknown. In this study, we aimed to discover the particular mechanism of RA treatment by microbiota by investigating the effects of ferroptosis on gut microbiota and its metabolites in collagen-induced arthritis (CIA) mice. Mice were divided into five groups: control, CIA, erastin, BzATP, and BzATP + erastin group. We performed 16S rDNA sequencing and metabolomics analysis on mouse feces and found that erastin and BzATP altered the microbiota and metabolites. The findings demonstrated that the microbiota was significantly disturbed at the phylum (Proteobacteria, Firmicutes, and Bacteroidota) and genus level (Lachnospiraceae_NK4A136, Lactobacillus, and Bifidobacterium) in the CIA group, and erastin exacerbated this disturbance. Unexpectedly, BzATP treatment could repair the disruptive effects of erastin. Additionally, there were significant variations in metabolites between each group. Erastin worsened metabolite abnormalities in CIA mice, while BzATP mitigated them, consistent with the microbiota results. These findings provide novel perspectives and insights into the therapy of RA.

SMSCs-derived sEV overexpressing miR-433-3p inhibits angiogenesis induced by sEV released from synoviocytes under triggering of ferroptosis.

BACKGROUND: Ferroptosis is characterized by accumulation of lipid peroxides that leads to oxidative stress. In progressive rheumatoid arthritis (RA), fibroblast-like synoviocytes (FLS) suffered from oxidative stress induced by generation of excess reactive oxygen species (ROS) and survived from elevated lipid oxidation. However the phenomenon of abnormal synovial fibroblasts proliferation under ferroptotic stress remain to be explained and the effects of this event on disease progression of RA need to be investigated. METHODS: FLS from RA patients (RA-FLS) were stimulated with LPS as an inflammatory model in vitro, and simultaneously treated with ferroptosis inducer Erastin/RSL3 or inhibitor ferrostatin-1. Besides, small extracellular vesicles (sEV) from the supernatant of RA-FLS culture under Erastin/RSL3 management were isolated. The degree of ferroptosis in cells were evaluated by Lipid-ROS detection via flowcytometry and ferroptosis marker protein expression determined by western bloting. The expression of core component of ESCRT-III CHMP4A and CHMP5 was determined by western bloting, and knockdown of CHMP4A was further performed to detect the influence of ESCRT-III complex on ferroptosis as well as LPS/Erastin induced sEV (LPS/Erastin-sEV) releasing. Moreover, miR-433-3p level in the isolated sEV was evaluated by RT-qPCR and interaction of miR-433-3p with FOXO1/VEGF axis were evaluated. MiR-433-3p was overexpressed in synovial mesenchymal stem cells (SMSCs) via miR-433-3p mimics transfection. RA-FLS was co-cultured with human dermal microvascular endothelial cells (HDMECs). LPS/Erastin-sEV or sEV derived from miR-433-3p-overexpressing SMSCs (miR-433-3p-SMSCs-sEV) were added to the co-culture system, and supernatants from co-culture without sEV were given to HDMECs. Angiogenic activity of HDMECs were identified by transwell test and endothelial tube formation analysis. Erastin-sEV and miR-433-3p-SMSCs-sEV were also administrated in collagen-induced arthritis (CIA) mouse model respectively, and progression of arthritis were evaluated. RESULTS: Ferroptosis of RA-FLS was triggered by LPS/Erastin and accompanied with increased expression of ESCRT-III core components as well as elevated release of sEV from RA-FLS. HDMECs' migration and tube formation in vitro was significantly induced/suppressed by supernatants from co-culture under management of Erastin-sEV/miR-433-3p-SMSCs-sEV due to varied VEGF expression regulated by miR-433-3p targeting FOXO1. MiR-433-3p-SMSCs-sEV could inhibit the Erastin-sEV promoted VEGF expression and mitigated arthritis severity. CONCLUSION: Erastin-sEV could aggravate synovial angiogenesis and promote arthritis progression. Administration of miR-433-3p-SMSCs-sEV may be a potential novel therapeutic method as significant antagonism to Erastin-sEV for RA treatment.

Potential predictive and therapeutic applications of small extracellular vesicles-derived circPARD3B in osteoarthritis.

Background: Heterogeneous phenotypes that display distinct common characteristics of osteoarthritis (OA) are not well defined and will be helpful in identifying more customized therapeutic options for OA. Circular RNAs (circRNAs) have attracted more and more attention due to their role in the progression of OA. Investigating the role of circRNAs in the pathogenesis of OA will contribute to the phenotyping of OA and to individualized treatment. Methods: Small extracellular vesicles (sEV) were isolated from serum samples from patients with OA of different stages and sEV-derived circPARD3B was determined using RT-qPCR analysis. CircPARD3B expression in a stimulated coculture that included OA fibroblast-like synoviocytes (OA-FLS) as well as human dermal microvascular endothelial cells (HDMECs), plus the effects of circPARD3B on the expression of vascular endothelial growth factor (VEGF) long with angiogenic activity, were evaluated in vitro. Based on bioinformatics analysis and luciferase reporter assay (LRA), MiR-326 and sirtuin 1 (SIRT1) were found to be interactive partners of circPARD3B. Mesenchymal stem cells (SMSCs) overexpressing circPARD3B were constructed and SMSCs-derived sEV with overexpressed circPARD3B (OE-circPARD3B-SMSCs-sEV) were obtained to explore the effect of the intervention of circPARD3B combined with SMSCs-sEV-based therapy in vitro and in a OA model induced by collagenase in vivo. Results: Serum sEV-linked circPARD3B was indentified to be significantly decreased in the inflammatory phenotype of OA. Overexpression of circPARD3B was found to inhibit the expression of VEGF, as well as the angiogenesis induced by VEGF in a IL-1ß stimulated the co-culture of OA-FLS as well as HDMECs. CircPARD3B is directly bound to miR-326. SIRT1 was considered a novel miR-326 target gene. OE-circPARD3B-SMSCs-sEV significantly reduced VEGF expression in coculture of OA-FLS and HDMECs. Injection of OE-circPARD3B-SMSCs-sEV could also reduce synovial VEGF; additionally, it could further ameliorate OA in the mouse model of OA in vivo. Conclusion: Serum sEV circPARD3B is a potential biomarker that enables the identification of the inflammatory phenotype of patients with OA. Correspondingly, intracellular transfer of circPARD3B through OE-circPARD3B-SMSCs-sEV could postpone disease progression through a functional module regulated angiogenesis of circPARD3B-miR-326-SIRT1, providing a novel therapeutic strategy for OA.

Orthodontic retreatment of an adult woman with mandibular backward positioning and temporomandibular joint disorder: A case report.

BACKGROUND: The role of occlusal factors on the occurrence of temporomandibular joint disorders (TMDs) is still unclear and it is tricky for orthodontists to treat malocclusions in patients with TMDs. We report the case of the second orthodontic treatment of an adult female with Class II division 2 malocclusion associated with TMD. With the removal of anterior occlusal interference, TMD symptoms were alleviated and cone beam computed tomography (CBCT) images showed the bilateral condyles shifted forward. CASE SUMMARY: This case report presented an orthodontic retreatment of an adult female with TMD and mandibular backward positioning based on CBCT examination and Joint Space Index (JSI) analysis. The left and right JSI values of -38.5 and -52.6 indicated that the position of bilateral condyles had posterior displacement. Ten years prior to this evaluation, she underwent orthodontic treatment resulting in the extraction of two upper premolars and one lower central incisor. The joint symptoms, including pain and sounds, were alleviated along with verified mandibular forward repositioning by extraction of another lower central incisor. CONCLUSION: Mandibular backward positioning could be associated with TMD. JSI analysis based on CBCT is a convenient way to examine condylar positions quantitatively.

Analysis of Methylation-driven Genes in Pancreatic Ductal Adenocarcinoma for Predicting Prognosis.

Purpose: Considerable variations in methylation profile have been found in various cancers to modulate tumorigenesis and affect prognosis. To provide a theoretical basis for early detection, prognosis evaluation and targeted treatment for patients with pancreatic ductal adenocarcinoma: PDAC, this study identified methylation-driven genes in PDAC and explored their prognostic performance. Methods: The methylation, expression and clinical data of PDAC patients were extracted from TCGA database. Based on the ß-mixture model of the MethylMix R package, the differential methylation status and connection between methylation and expression degree were examined to screen out methylation-driven genes in PDAC. COX analyses and lasso regressions were applied to construct a linear risk model based on methylation-driven genes. Univariate and multivariate analyses were performed to ensure the risk model was an independent prognostic factor. Joint survival analyses of methylation and gene expression were conducted to explore the prognostic value of component genes. The methylation sites in the key genes were also investigated. Results: A total of 118 methylation-driven genes in PDAC were identified, and two genes (FOXI2, MYEOV) constituted the risk model whose AUC was 0.722 at one year of overall survival rate, displaying a better performance on survival prediction than other clinical features. Further survival analyses demonstrated that the expression of MYEOV and combined methylation and expression levels of the genes MYEOV and FOXI2 can be potential biomarkers for survival prediction and targets of drug manipulation of PDAC patients. Close relationships were discovered between two sites in MYEOV and one site in FOXI2 and the prognosis of PDAC patients. Conclusion: Concentrating on DNA methylation, our study identified potential biomarkers and developed a reliable short-term predictive model for prognosis of PDAC patients.

D-mannose alleviates osteoarthritis progression by inhibiting chondrocyte ferroptosis in a HIF-2α-dependent manner.

OBJECTIVES: Chondrocyte ferroptosis contributes to osteoarthritis (OA) progression, and D-mannose shows therapeutic value in many inflammatory conditions. Here, we investigated whether D-mannose interferes in chondrocyte ferroptotic cell death during osteoarthritic cartilage degeneration. MATERIALS AND METHODS: In vivo anterior cruciate ligament transection (ACLT)-induced OA mouse model and an in vitro study of chondrocytes in an OA microenvironment induced by interleukin-1ß (IL-1ß) exposure were employed. Combined with Epas1 gene gain- and loss-of-function, histology, immunofluorescence, quantitative RT-PCR, Western blot, cell viability and flow cytometry experiments were performed to evaluate the chondroprotective effects of D-mannose in OA progression and the role of hypoxia-inducible factor 2 alpha (HIF-2 α) in D-mannose-induced ferroptosis resistance of chondrocytes. RESULTS: D-mannose exerted a chondroprotective effect by attenuating the sensitivity of chondrocytes to ferroptosis and alleviated OA progression. HIF-2α was identified as a central mediator in D-mannose-induced ferroptosis resistance of chondrocytes. Furthermore, overexpression of HIF-2α in chondrocytes by Ad-Epas1 intra-articular injection abolished the chondroprotective effect of D-mannose during OA progression and eliminated the role of D-mannose as a ferroptosis suppressor. CONCLUSIONS: D-mannose alleviates osteoarthritis progression by suppressing HIF-2α-mediated chondrocyte sensitivity to ferroptosis, indicating D-mannose to be a potential therapeutic strategy for ferroptosis-related diseases.

METTL3-Mediated lncRNA m6A Modification in the Osteogenic Differentiation of Human Adipose-Derived Stem Cells Induced by NEL-Like 1 Protein.

OBJECTIVES: This study aimed to explore the regulatory mechanism of methyltransferase3 (METTL3) -mediated long non-coding RNA (lncRNA) N6-methyladenosine (m6A) modification in the osteogenic differentiation of human adipose-derived stem cells (hASCs) induced by NEL-like 1 protein (NELL-1). MATERIALS AND METHODS: Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and high- throughput sequencing for RNA (RNA-seq) were performed on hASCs. Osteogenic ability was detected by alkaline phosphatase (ALP) staining, Alizarin Red S(ARS) staining, ALP quantification and Quantitative real-time polymerase chain reaction analysis (qRT-PCR). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis predicted the osteogenesis-related pathways enriched for the lncRNAs and identified the target lncRNAs. After overexpression and knockdown of METTL3, methylated RNA immunoprecipitation-qPCR (MeRIP-qPCR) and qRT-PCR were used to detect the levels of m6A modification and the expression of the target lncRNA, and the binding of both was confirmed by RNA binding protein immunoprecipitation (RIP) assay. The effects of lncRNA and METTL3 on phosphorylation of the key proteins of the pathway were detected by western blot analysis. RESULTS: In vitro experiments showed that METTL3 can promote osteogenic differentiation and that its expression level is upregulated. KEGG pathway analysis predicted that lncRNAs with differentially upregulated methylated peaks were enriched mostly in the mitogen-activated protein kinase (MAPK) signaling pathway, in which Serine/threonine protein kinase 3 (STK3) was the predicted target gene of the lncRNA RP11-44 N12.5. The m6A modification and expression of RP11-44 N12.5 were both regulated by METTL3. Subsequently, lncRNA RP11-44 N12.5 and METTL3 were found to regulate the phosphorylation levels of three key proteins in the MAPK signaling pathway, ERK, JNK and p38. CONCLUSIONS: This study shows, for the first time, that METTL3 can activate the MAPK signaling pathway by regulating the m6A modification and expression of a lncRNA, thereby enhancing the osteogenic differentiation of hASCs.

Transcriptome-wide m6A methylome during osteogenic differentiation of human adipose-derived stem cells.

OBJECTIVES: Adipose-derived stem cells are frequently used for bone regeneration both in vitro and in vivo. N6-methyladenosine (m6A) is the most abundant post-transcriptional modification on eukaryotic RNAs and plays multifaceted roles in development and diseases. However, the regulatory mechanisms of m6A in osteogenic differentiation of human adipose-derived stem cells (hASCs) remain elusive. The present study aimed to build the transcriptome-wide m6A methylome during the osteogenic differentiation of hASCs. MATERIALS AND METHODS: hASCs were harvested after being cultured in a basic or osteogenic medium for 7 days, and the osteogenic differentiation was validated by alkaline phosphatase (ALP) and Alizarin Red S staining, ALP activity assay, and qRT-PCR analysis of ALP, RUNX2, BGLAP, SPP1, SP7, and COL1A1 genes. The m6A level was colorimetrically measured, and the expression of m6A regulators was confirmed by qRT-PCR and western blot. Moreover, m6A MeRIP-seq and RNA-seq were performed to build the transcriptome and m6A methylome. Furthermore, bioinformatic analyses including volcano plots, Venn plots, clustering analysis, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, gene sets enrichment analysis, and protein-protein interaction analysis were conducted. RESULTS: In total, 1145 differentially methylated peaks, 2261 differentially expressed genes, and 671 differentially methylated and expressed genes (DMEGs) were identified. GO and KEGG pathway analyses conducted for these DMEGs revealed extensive and osteogenic biological functions. The "PI3K-Akt signaling pathway"; "MAPK signaling pathway"; "parathyroid hormone synthesis, secretion, and action"; and "p53 signaling pathway" were significantly enriched, and the DMEGs in these pathways were identified as m6A-specific key genes. A protein-protein interaction network based on DMEGs was built, and VEGFA, CD44, MMP2, HGF, and SPARC were speculated as the hub DMEGs. CONCLUSIONS: The total m6A level was reduced with osteogenic differentiation of hASCs. The transcriptome-wide m6A methylome built in the present study indicated quite a few signaling pathways, and hub genes were influenced by m6A modification. Future studies based on these epigenetic clues could promote understanding of the mechanisms of osteogenic differentiation of hASCs.

Effects of fixed functional appliances with temporary anchorage devices on Class II malocclusion: A systematic review and meta­analysis.

BACKGROUND: The use of fixed functional appliances (FFAs) in conjunction with temporary anchorage devices (TADs) has been proposed to enhance skeletal changes and reduce proclination of the lower incisors. OBJECTIVES: To systematically investigate the skeletal and dentoalveolar effects of FFAs with TADs on Class II malocclusion in adolescents. METHODS: Electronic searches of databases and manual searches of references were performed up to August 30, 2020. Randomized controlled trials (RCTs) and clinical controlled trials (CCTs) focusing on adolescent patients treated with FFAs combining TADs were included. The modified Cochrane risk-of-bias tool (R.O.B 2.0) and ROBINS-I (Risk of Bias in Non-randomized Studies-of Interventions) Tool were used to assess the risk of bias in RCTs and CCTs, respectively. Meta-analyses of SNA, SNB, ANB, Co-Gn, SN-MP, the lower and upper incisor inclination changes were performed. Subgroup analyses and sensitivity analyses were conducted based on TAD types, FFA types, record types and types of study designs. RESULTS: Ten studies were included with a sample size of 281. Meta-analyses revealed significant differences in the changes in SNB (mean difference [MD] 0.67; 95% confidence interval [CI] 0.04-1.29), ANB (MD -1.22, 95% CI -2.04 to -0.39), Co-Gn (MD 1.57; 95% CI 0.22-2.92), inclination of the lower incisors (MD -5.64, 95% CI -7.78 to -3.50)] and inclination of the upper incisors (MD -1.91; 95% CI -3.69 to -0.13). TAD types and FFA types seem to affect the treatment outcome. CONCLUSIONS: Compared with FFAs alone, FFAs with TADs exhibit superior skeletal effects and reduce the inclination of the lower incisors in the short term; however, the evidence showed moderate to high risk of bias. Registration number CRD42020177611.

Dentofacial characteristics and age in association with incisor bony support in adult female patients with bimaxillary dentoalveolar protrusion.

OBJECTIVE: The aim of this study was to analyse the correlation between incisor alveolar bone thickness (IABT) and dentofacial characteristics or age in adult female patients with bimaxillary dentoalveolar protrusion (BDP). Evaluating the contribution of these characteristics may help to predict the IABT differences in this patient population. SETTING AND SAMPLE POPULATION: A retrospective study whose sample comprised 80 pretreatment adult female patients with BDP (mean age 24.6 years). MATERIALS AND METHODS: The IABT of the bimaxillary central incisors was measured by cone-beam computed tomography. Among the types of IABT, the apical trabecular bone thickness was measured with a quantitative method. The sagittal skeletal pattern, facial divergence, the incisor inclination angle, and mandibular plane angulation were determined by cephalometric analysis. A backward linear multiple regression was performed to analyse the associations between IABT and these characteristics. RESULTS: Three dentofacial traits and age were associated with IABT. Patients with increased age and facial divergence tended to have a thinner mandibular incisor bone support, while increased root length was associated with a thicker mandibular incisor apical bone thickness. Increased U1-SN and facial divergence may lead to a thinner maxillary incisor palatal bone, while increased U1-SN resulted in a thicker maxillary incisor labial bone. CONCLUSIONS: The bony support of the incisors is associated with age and dentofacial traits. Increasing age and facial divergence are considered risk factors for alveolar defects in female patients with BDP. In contrast, increased root length is associated with a thicker mandibular incisor apical bone support.

Influence of different types of rapid maxillary expansion on root resorption: a systematic review.

OBJECTIVES: This study aimed to assess the influence of different types of rapid maxillary expansion on root resorption (RR). METHODS: Literature searches were carried out electronically in five English and two Chinese databases. Randomized controlled trials (RCTs), controlled clinical trials (CCTs), cohort studies, and case-control studies were included. The data were extracted by three authors. The risk of bias in the RCTs and nonrandomized studies were assessed in accordance with corresponding scales. RESULTS: Among the 400 articles identified, seven were included for the final analysis. Three studies were graded as high value of evidence, while two and another two studies were graded as moderate value and low value, respectively. According to the available evidence, the tooth-borne maxillary expansion caused more obvious RR of anchorage teeth than the bone-borne one. In addition, the Haas-type palatal acrylic pads could not effectively reduce the degree of RR. The difference in the design of the retainer between the tooth-borne maxillary expansion (the use of a band or wire framework to connect the anchorage tooth) did not cause the difference in the incidence and degree of RR. CONCLUSIONS: Clinical evidence suggested that bone-borne maxillary expansion may decrease the amount of RR, while the amounts of resorption did not significantly differ between Haas and Hyrax and between different retainer types of Hyrax.

Study on the mechanism of degradation of tetracycline hydrochloride by microwave-activated sodium persulfate.

Among the different antibiotics, tetracycline hydrochloride (TCH) is one of the most commonly used. In this study, the activated sodium persulfate (SPS) process induced by microwave (MW) energy was used to treat TCH. The effect of different operational parameters of MW/SPS-treated TCH, such as SPS concentration, TCH concentration, initial pH, and MW power, was investigated. The concentration changes of TCH were determined using a spectrophotometer. The results of radical scavenger experiments indicated that the sulfate radical (SO4 ·-) was stronger than the hydroxyl radical (·OH). On the basis of high performance liquid chromatography-mass spectrometry (HPLC-MS) analysis, a possible degradation pathway of TCH was proposed. This research indicates that the MW/SPS system is a promising prospect for the treatment of TCH.

Correction to: Treatment of the mandibular shift in an adult woman and the diagnostic value of joint space index: a case report.

An amendment to this paper has been published and can be accessed via the original article.

Treatment of the mandibular shift in an adult woman and the diagnostic value of joint space index: a case report.

BACKGROUND: Mandibular deviations are common clinical complaints. The orthodontic or orthognathic treatment of mandibular deviations is tricky because a comprehensive diagnosis, especially a functional one, is difficult to make. A inaccurate diagnosis may lead to a compromised and unstable treatment outcome. CASE PRESENTATION: This article describes the diagnosis and treatment of a woman with a mandibular deviation and facial skeletal asymmetry. By eliminating the disharmony of the arch form with elastics and bite turbos, her esthetic and functional outcomes improved. Cone-beam CT (CBCT) and Joint Space Index (JSI) analyses served as the diagnostic approaches and outcome evaluation methods before and after treatment. CONCLUSIONS: A condyle position displacement could be an indication of functional deviation. JSI analysis is a quantitative and convenient choice to compare condyle relative positions.

DNA methylation of noncoding RNAs: new insights into osteogenesis and common bone diseases.

Bone diseases such as osteoarthritis, osteoporosis, and bone tumor present a severe public health problem. Osteogenic differentiation is a complex process associated with the differentiation of different cells, which could regulate transcription factors, cytokines, many signaling pathways, noncoding RNAs (ncRNAs), and epigenetic modulation. DNA methylation is a kind of stable epigenetic alterations in CpG islands without DNA sequence changes and is involved in cancer and other diseases, including bone development and homeostasis. ncRNAs can perform their crucial biological functions at the RNA level, and many findings have demonstrated essential functions of ncRNAs in osteogenic differentiation. In this review, we highlight current researches in DNA methylation of two relevant ncRNAs, including microRNAs and long noncoding RNAs, in the initiation and progression of osteogenesis and bone diseases.

microRNA expression profiles and the potential competing endogenous RNA networks in NELL-1-induced human adipose-derived stem cell osteogenic differentiation.

Studies have indicated that Nel-like molecule-1 (NELL-1) was an osteoblast-specific cytokine and some specific microRNAs (miRNAs) could serve as competing endogenous RNA (ceRNA) to partake in osteogenic differentiation of human adipose-derived stem cells (hASCs). The aim of this study was to explore the potential functional mechanisms of recombinant human NELL-1 protein (rhNELL-1) during hASCs osteogenic differentiation. rhNELL-1 was added to osteogenic medium to activate osteogenic differentiation of hASCs. High-throughput RNA sequencing (RNA-Seq) was performed and validated by real-time quantitative polymerase chain reaction. Gene ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway analysis were performed to detect the functions of differentially expressed miRNAs and genes. Coding-noncoding gene co-expression network and ceRNA networks were constructed to predict the potential regulatory role of miRNAs. A total of 1010 differentially expressed miRNAs and 1762 differentially expressed messenger RNAs (mRNAs) were detected. miRNA-370-3p, bone morphogenetic protein 2 (BMP2), and parathyroid hormone like hormone (PTHLH) were differentially expressed during NELL-1-induced osteogenesis. Bioinformatic analyses demonstrated that these differentially expressed miRNAs and mRNAs enriched in Rap1 signaling pathway, PI3K-Akt signaling pathway, p53 signaling pathway, Glucagon signaling pathway, and hypoxia-inducible factor-1 signaling pathway, which were important pathways related to osteogenic differentiation. In addition, miRNA-370-3p and has-miR-485-5p were predicted to interact with circ0001543, circ0002405, and ENST00000570267 in ceRNA networks. Based on the gain or loss of functional experiments by transfection, the results showed that miR-370-3p was a key regulator in osteogenic differentiation by targeting BMP2 and disturbing the expression of PTHLH, and participated in NELL-1-stimulated osteogenesis. The present study provided the primary data and evidence for further exploration on the roles of miRNAs and ceRNAs during NELL-1-induced ossification of hASCs.

Long noncoding RNA expression profiles during the NEL-like 1 protein-induced osteogenic differentiation.

Long noncoding RNAs (lncRNAs) are important modulators of mesenchymal stem cells (MSCs) in cellular differentiation. However, the regulatory mechanisms of lncRNAs in NEL-like 1 (NELL-1)-induced osteogenic differentiation of human adipose-derived stem cells remain elusive. Expression profiles of lncRNAs and messenger RNAs during NELL-1-induced osteogenesis were obtained using high-throughput sequencing. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes pathway analysis, and gene coexpression networks were performed. We identified 323 statistically differentially expressed lncRNAs during osteogenesis and NELL-1-induced osteogenesis, and three lncRNAs (ENST00000602964, ENST00000326734, and TCONS_00006792) were identified as core regulators. Hedgehog pathway markers, including IHH and GLI1, were downregulated, while the antagonists of this pathway (GLI3 and HHIP) were upregulated during NELL-1-induced osteogenesis. In this process, the antagonist of Wnt, SFRP1, was downregulated. According to the analysis, we speculated that lncRNAs played important roles in NELL-1-induced osteogenesis via the crosstalk between Hedgehog and Wnt pathways.