The diagnostic value and pathogenetic role of lncRNA-ATB in patients with osteoarthritis

mHealth-based exercise vs. traditional exercise on pain, functional disability, and quality of life in patients with knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials

Objective

This study aims to compare the efficacy of mHealth-based exercise interventions with traditional exercise in improving pain intensity, functional disability, and quality of life in patients suffering from knee osteoarthritis (OA).

Method

Randomized controlled trials (RCTs) published from their inception to 23 August 2024 were searched in Cochrane, Embase, Medline, Web of Science. Reviewer pairs independently extracted data and evaluated bias using the Cochrane Risk of Bias tool.

Results

Eleven studies, with a total of 800 participants with a mean age of 55.51 ± 6.88 years, were identified. All RCTs were performed from 2013 to 2024. There was no statistically significant difference between mHealth-supported exercise compared with the traditional exercise without mHealth in terms of pain reduction (standard mean differences [SMD] = -0.35; 95%CI: -0.74 to 0.04, P = 0.08), functional disability (SMD = -0.5; 95%CI: -0.1 to 0.01; P = 0.05), and quality of life (SMD = 0.11; 95%CI: -0.26 to 0.48; P = 0.56). However, a statistically significant difference was found between mHealth-supported exercise compared with unsupervised traditional exercise in terms of pain (SMD = -1.03; 95%CI: -1.49 to -0.57; P < 0.001) and functional disability (SMD = -0.89; 95%CI: -1.71 to -0.06; P = 0.04).

Conclusion

mHealth-based exercise was found to be more effective than unsupervised conventional exercise in promoting pain relief and enhancing functional disability in patients with OA. When face-to-face exercise intervention is not feasible, mHealth-based exercise should be considered a viable option in the recovery process for knee OA. Given the significant heterogeneity observed in this study, it is important to exercise caution when extrapolating the results.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/#recordDetails, identifier CRD42024610393.

Bioactive Compounds and Their Chondroprotective Effects for Osteoarthritis Amelioration: A Focus on Nanotherapeutic Strategies, Epigenetic Modifications, and Gut Microbiota

In degenerative joint disease like osteoarthritis (OA), bioactive compounds like resveratrol, epigallocatechin gallate, curcumin, and other polyphenols often target various signalling pathways, including NFκB, TGFβ, and Wnt/β-catenin by executing epigenetic-modifying activities. Epigenetic modulation can target genes of disease pathophysiology via histone modification, promoter DNA methylation, and non-coding RNA expression, some of which are directly involved in OA but have been less explored. OA patients often seek options that can improve the quality of their life in addition to existing treatment with nonsteroidal anti-inflammatory drugs (NSAIDs). Although bioactive and natural compounds exhibit therapeutic potential against OA, several disadvantages loom, like insolubility and poor bioavailability. Nanoformulated bioactive compounds promise a better way to alleviate OA since they also control systemic events, including metabolic, immunological, and inflammatory responses, by modulating host gut microbiota that can regulate OA pathogenesis. Recent data suggest gut dysbiosis in OA. However, limited evidence is available on the role of bioactive compounds as epigenetic and gut modulators in ameliorating OA. Moreover, it is not known whether the effects of polyphenolic bioactive compounds on gut microbial response are mediated by epigenetic modulatory activities in OA. This narrative review highlights the nanotherapeutic strategies utilizing bioactive compounds, reporting their effects on chondrocyte growth, metabolism, and epigenetic modifications in osteoarthritis amelioration.

Deciphering the Role of LncRNAs in Osteoarthritis: Inflammatory Pathways Unveiled

Long non-coding RNA (LncRNA), with transcripts over 200 nucleotides in length, play critical roles in numerous biological functions and have emerged as significant players in the pathogenesis of osteoarthritis (OA), an inflammatory condition traditionally viewed as a degenerative joint disease. This review comprehensively examines the influence of LncRNA on the inflammatory processes driving OA progression, focusing on their role in regulating gene expression, cellular activities, and inflammatory pathways. Notably, LncRNAs such as MALAT1, H19, and HOTAIR are upregulated in OA and exacerbate the inflammatory milieu by modulating key signaling pathways like NF-κB, TGF-β/SMAD, and Wnt/β-catenin. Conversely, LncRNA like MEG3 and GAS5, which are downregulated in OA, show potential in dampening inflammatory responses and protecting against cartilage degradation by influencing miRNA interactions and cytokine production. By enhancing our understanding of LncRNA' roles in OA inflammation, we can better leverage them as potential biomarkers for the disease and develop innovative therapeutic strategies for OA management. This paper aims to delineate the mechanisms by which LncRNA influence inflammatory responses in OA and propose them as novel targets for therapeutic intervention.

Unraveling the molecular landscape of osteoarthritis: A comprehensive review focused on the role of non-coding RNAs

Osteoarthritis (OA) poses a significant global health challenge, with its prevalence anticipated to increase in the coming years. This review delves into the emerging molecular biomarkers in OA pathology, focusing on the roles of various molecules such as metabolites, noncoding RNAs (ncRNAs), including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). Advances in omics technologies have transformed biomarker identification, enabling comprehensive analyses of the complex pathways involved in OA pathogenesis. Notably, ncRNAs, especially miRNAs and lncRNAs, exhibit dysregulated expression patterns in OA, presenting promising opportunities for diagnosis and therapy. Additionally, the intricate interplay between epigenetic modifications and OA progression highlights the regulatory role of epigenetics in gene expression dynamics. Genome-wide association studies have pinpointed key genes undergoing epigenetic changes, providing insights into the inflammatory processes and chondrocyte hypertrophy typical of OA. Understanding the molecular landscape of OA, including biomarkers and epigenetic mechanisms, holds significant potential for developing innovative diagnostic tools and therapeutic strategies for OA management.

WITHDRAWN: The dysregulated autophagy in osteoarthritis: Revisiting molecular profile

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LINC00839 in Human Disorders: Insights into its Regulatory Roles and Clinical Impact, with a Special Focus on Cancer

LINC00839 has captured significant attention within a spectrum of human disorders, including acute lung injury, osteoarthritis, and childhood obesity. Notably, aberrant expression patterns of LINC00839 have been observed across diverse cancer tissues and cell lines. LINC00839 emerges as an oncogenic factor in tumorigenesis and exerts a positive influence on tumor-associated behaviors. Its therapeutic potential for various cancers is underscored by its modulatory impact on pivotal signaling pathways, such as PI3K/AKT, OXPHOS, and Wnt/β-catenin. Additionally, LINC00839's role in reducing sensitivity to drug and radiotherapy interventions presents opportunities for targeted intervention. Furthermore, elevated LINC00839 expression indicates advanced clinicopathological features and foretells unfavorable prognoses, as validated by publications and comprehensive analyses of tumor types using TCGA datasets. This review elucidates the multiple regulatory mechanisms and functional implications of LINC00839 in various diseases, especially malignancies, emphasizing its potential as a predictive biomarker and therapeutic target across multiple disease domains in humans.

Biological functions and applications of LncRNAs in the regulation of the extracellular matrix in osteoarthritis

Osteoarthritis (OA) is a major cause of disability, characterized by chronic pain, irreversible destruction, and loss of function of the articular cartilage. The integrity and arrangement of the composition and structure of the extracellular matrix (ECM) are essential for maintaining the elasticity, integrity, and mechanical support function of the cartilage tissue. Osteoarthritis causes substantial changes in the ECM, driving the progression of the disease. Recent studies have shown that the ECM plays a critical role in the development of cartilage tissue as well as the occurrence and development of osteoarthritis by directly or indirectly regulating chondrocyte proliferation, apoptosis, differentiation, and gene expression. Long non-coding RNAs (lncRNAs) are a class of non-coding RNAs derived from large transcripts. Mutations and disorders of lncRNAs are closely related to the development of osteoarthritis. Abnormal expression of lncRNAs in osteoarthritic cartilage regulates the synthesis and decomposition of the cartilaginous ECM. Therefore, the use of lncRNAs as nucleic acid drugs that regulate their targets may reduce ECM degradation, thereby delaying the pathological progression of osteoarthritis. In this review, the regulatory effects of lncRNAs on ECM in different cell behaviors related to OA are summarized. The roles of lncRNAs in the proliferation, apoptosis, differentiation, and ECM-related gene activity of chondrocytes, as well as the application of lncRNAs as potential gene therapy drugs for the repair and regeneration of osteoarthritic tissue, are also reviewed. A better understanding of the roles of lncRNAs in guiding chondrocyte behavior and ECM metabolism is critical for their future applications in osteoarthritis therapy and regenerative medicine.

Association of lncRNA THRIL, HOTAIR genes variations and expression levels with pulmonary tuberculosis

BACKGROUND

Long non-coding RNA (lncRNA) has been implicated in the pathogenesis of pulmonary tuberculosis (PTB). This study aims to investigate the involvement of lncRNA THRIL and HOTAIR gene single nucleotide polymorphisms (SNPs) and their expression levels in PTB susceptibility.

METHODS

A total of 456 PTB patients and 464 healthy controls participated in our study. we genotyped six SNPs of THRIL and HOTAIR genes using an improved multiple ligase detection reaction (iMLDR). Additionally, real-time reverse-transcriptase polymerase chain reaction was employed to detect the expression levels of THRIL and HOTAIR in peripheral blood mononuclear cells (PBMC) from 78 PTB patients and 84 healthy controls.

RESULTS

No significant differences in allele and genotype frequencies were observed for THRIL rs1055472, rs11058000, and HOTAIR rs12427129, rs1899663, rs4759314, and rs7958904 polymorphisms between PTB patients and healthy controls (all P > 0.05). Moreover, genotype frequencies of all SNPs did not show any association with PTB susceptibility in the dominant-recessive model. However, the frequencies of rs7958904 CC genotype and C allele in the HOTAIR gene were significantly correlated with leukopenia in PTB patients. Furthermore, the expression levels of the HOTAIR gene were significantly elevated in PTB patients compared to controls.

CONCLUSIONS

Our study indicates that THRIL and HOTAIR gene SNPs might not contribute to PTB susceptibility, while the level of HOTAIR was increased in PTB patients.

[Identification of Characteristic lncRNA Molecular Markers in Osteoarthritis by Integrating GEO Database and Machine Learning Strategies and Experimental Validation]

Objective

To screen for long non-coding RNA (lncRNA) molecular markers characteristic of osteoarthritis (OA) by utilizing the Gene Expression Omnibus (GEO) database combined with machine learning.

Methods

The samples of 185 OA patients and 76 healthy individuals as normal controls were included in the study. GEO datasets were screened for differentially expressed lncRNAs. Three algorithms, the least absolute shrinkage and selection operator (LASSO), support vector machine recursive feature elimination (SVM-RFE), and random forest (RF), were used to screen for candidate lncRNA models and receiver operating characteristic (ROC) curves were plotted to evaluate the models. We collected the peripheral blood samples of 30 clinical OA patients and 15 health controls and measured the immunoinflammatory indicators. RT-PCR was performed for quantitative analysis of the expression of lncRNA molecular markers in peripheral blood mononuclear cells (PBMC). Pearson analysis was performed to examine the correlation between lncRNA and indicators for inflammation of the immune system.

Results

A total of 14 key markers were identified with LASSO, 6 genes were identified with SVM-RFE, and 24 genes were identified with RF. Venn diagram was used to screen for overlapping genes identified with the three algorithms, showing HOTAIR, H19, MIR155 HG, and NKILA to be the overlapping genes. The ROC curves showed that these four lncRNAs all had an area under the curve ( AUC) greater than 0.7. The RT-PCR findings revealed relatively elevated expression of HOTAIR, H19, and MIR155HG and decreased expression of NKILA in the PBMC of OA patients compared with those of the normal group ( P<0.01). The results were consistent with the bioinformatics predictions. Pearson analysis showed that the candidate lncRNAs were correlated with clinical indicators for inflammation.

Conclusion

HOTAIR, H19, MIR155 HG, and NKILA can be used as molecular markers for the clinical diagnosis of OA and are correlate with clinical indicators of inflammation of the immune system.

Advances in Research on the Regulatory Roles of lncRNAs in Osteoarthritic Cartilage

Osteoarthritis (OA) is the most common degenerative bone and joint disease that can lead to disability and severely affect the quality of life of patients. However, its etiology and pathogenesis remain unclear. It is currently believed that articular cartilage lesions are an important marker of the onset and development of osteoarthritis. Long noncoding RNAs (lncRNAs) are a class of multifunctional regulatory RNAs that are involved in various physiological functions. There are many differentially expressed lncRNAs between osteoarthritic and normal cartilage tissues that play multiple roles in the pathogenesis of OA. Here, we reviewed lncRNAs that have been reported to play regulatory roles in the pathological changes associated with osteoarthritic cartilage and their potential as biomarkers and a therapeutic target in OA to further elucidate the pathogenesis of OA and provide insights for the diagnosis and treatment of OA.

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.

The function of LncRNA-ATB in cancer

Cancer as a progressive and complex disease is caused by early chromosomal changes and stimulated cellular transformation. Previous studies reported that long non-coding RNAs (lncRNAs) play pivotal roles in the initiation, maintenance, and progression of cancer cells. LncRNA activated by TGF-β (ATB) has been shown to be dysregulated in different types of cancer. Aberrant expression of lncRNA-ATB plays an important role in the progression of diverse malignancies. High expression of LncRNA-ATB is associated with cancer cell growth, proliferation, metastasis, and EMT. LncRNA-ATB by targeting various signaling pathways and microRNAs (miRNAs) can trigger cancer pathogenesis. Therefore, lncRNA-ATB can be a novel target for cancer prediction and diagnosis. In this review, we will focus on the function of lncRNA-ATB in various types of human cancers.

Correlation of synovial tissue protein abundance with menopause in osteoarthritis

BACKGROUND

Osteoarthritis (OA) is a common articular disorder. Epidemiologic surveys show a higher prevalence of OA in women than men and that morbidity is higher during menopause. We aimed to explore whether menopause influences the clinical recovery of a knee joint following OA and injury, and identify associated mechanisms by analyzing the proteomic profile of synovial tissue (ST) samples.

METHODS

Routine blood examination and hormone level tests were conducted before surgery. ST samples from eight participants were collected intraoperatively for proteomic analysis. One day before and one month after the surgery, we assessed various aspects of function in the affected knee including the with Visual Analog Score (VAS), Lysholm, The Western Ontario, and McMaster Universities Osteoarthritis Index (WOMAC) scores. The relationships between proteomic data, estrogen levels, and affected knee function were compared and analyzed. This was a retrospective study.

RESULT

Menopause was associated with the clinical outcomes of knee OA and knee injuries. ST proteomic data identified that 80 proteins in premenopausal OA females were significantly different from menopausal OA females. In addition, 100 proteins were significantly different between premenopausal OA females and premenopausal injured females.

CONCLUSIONS

Age and menopause showed a positive correlation with the protein profile of ST from OA or knee injury female patients, indicating that the protein components might be affected by menopause. Postoperative clinical outcomes were affected by menopause. We conclude that menopause may, in part, regulate knee joint function by altering ST protein expression.

Emerging role of lncRNAs in osteoarthritis: An updated review

Osteoarthritis (OA) is a prevalent joint disease, which is associated with progressive articular cartilage loss, synovial inflammation, subchondral sclerosis and meniscus injury. The molecular mechanism underlying OA pathogenesis is multifactorial. Long non-coding RNAs (lncRNAs) are non-protein coding RNAs with length more than 200 nucleotides. They have various functions such as modulating transcription and protein activity, as well as forming endogenous small interfering RNAs (siRNAs) and microRNA (miRNA) sponges. Emerging evidence suggests that lncRNAs might be involved in the pathogenesis of OA which opens up a new avenue for the development of new biomarkers and therapeutic strategies. The purpose of this review is to summarize the current clinical and basic experiments related to lncRNAs and OA with a focus on the extensively studied H19, GAS5, MALAT1, XIST and HOTAIR. The potential translational value of these lncRNAs as therapeutic targets for OA is also discussed.

LncRNAs in Osteoarthritis

Osteoarthritis (OA) is a progressive joint disease that affects millions of older adults around the world. With increasing rates of incidence and prevalence worldwide, OA has become an enormous global socioeconomic burden on healthcare systems. Long non-coding ribonucleic acids (lncRNAs), essential functional molecules in many biological processes, are a group of non-coding RNAs that are greater than approximately 200 nucleotides in length. Fast-growing and recent developments in lncRNA research are captivating and represent a novel and promising field in understanding the complexity of OA pathogenesis. The involvement of lncRNAs in OA's pathological processes and their altered expressions in joint tissues, blood and synovial fluid make them attractive candidates for the diagnosis and treatment of OA. We focus on the recent advances in major regulator mechanisms of lncRNAs in the pathophysiology of OA and discuss potential diagnostic and therapeutic uses of lncRNAs for OA. We investigate how upregulation or downregulation of lncRNAs influences the pathogenesis of OA and how we can use lncRNAs to elucidate the molecular mechanism of OA. Furthermore, we evaluate how we can use lncRNAs as a diagnostic marker or therapeutic target for OA. Our study not only provides a comprehensive review of lncRNAs regarding OA's pathogenesis but also contributes to the elucidation of its molecular mechanisms and to the development of diagnostic and therapeutic approaches for OA.

Missing lnc(RNAs) in Alzheimer's Disease?

With the ongoing demographic shift towards increasingly elderly populations, it is estimated that approximately 150 million people will live with Alzheimer's disease (AD) by 2050. By then, AD will be one of the most burdensome diseases of this and potentially next centuries. Although its exact etiology remains elusive, both environmental and genetic factors play crucial roles in the mechanisms underlying AD neuropathology. Genome-wide association studies (GWAS) identified genetic variants associated with AD susceptibility in more than 40 different genomic loci. Most of these disease-associated variants reside in non-coding regions of the genome. In recent years, it has become clear that functionally active transcripts arise from these non-coding loci. One type of non-coding transcript, referred to as long non-coding RNAs (lncRNAs), gained significant attention due to their multiple roles in neurodevelopment, brain homeostasis, aging, and their dysregulation or dysfunction in neurological diseases including in AD. Here, we will summarize the current knowledge regarding genetic variations, expression profiles, as well as potential functions, diagnostic or therapeutic roles of lncRNAs in AD. We postulate that lncRNAs may represent the missing link in AD pathology and that unraveling their role may open avenues to better AD treatments.

Neohesperidin promotes the osteogenic differentiation of human bone marrow stromal cells by inhibiting the histone modifications of lncRNA SNHG1

Neohesperidin (NH) was reported to regulate osteoclastic differentiation, while LncRNA SNHG1 could inhibit osteogenic differentiation of bone marrow stromal cells (BMSCs). In this study, we aimed to explore whether SNHG1-mediated osteogenic differentiation could be regulated by NH. Osteonecrosis and adjacent tissues, as well as normal bone marrow samples were gathered. BMSCs were isolated from normal bone marrow samples by Ficoll density gradient and identified by flow cytometry. Histopathological changes of tissues were detected by hematoxylin-eosin staining. After the treatment with NH or transfection, cell viability, osteogenic differentiation, and the activity of alkaline phosphatase (ALP) in BMSCs were detected by MTT, alizarin red staining, and microplate method, respectively. The histone modification and expressions of SNHG1 and osteogenic marker genes in tissues or BMSCs were detected by q-PCR and Chromatin Immunoprecipitation (ChIp). SNHG1 was highly expressed in osteonecrosis tissues, and typical signs of empty lacunae appeared in the necrotic tissues zone. NH increased viability and osteogenic differentiation of BMSCs, activity of ALP, and expressions of RUNX2, OCN and ALP. NH decreased both SNHG1 expression and H3K4me3 (activating histone modification) occupancies and increased H3K27me3 (inhibiting histone modification) occupancies of SNHG1. Furthermore, siSNHG1 enhanced osteogenic differentiation of BMSCs and expressions of RUNX2, OCN and ALP, while SNHG1 overexpression did the opposite and reversed the effects of NH on the osteogenic differentiation of BMSCs. In a word, NH promotes the osteogenic differentiation of human BMSCs by inhibiting the histone modifications of lncRNA SNHG1.

Long non-coding RNA KCNQ1OT1 promotes cell viability and migration as well as inhibiting degradation of CHON-001 cells by regulating miR-126-5p/TRPS1 axis

BACKGROUND

Osteoarthritis (OA) is defined as a degenerative disease. Pivotal roles of long non-coding RNA (lncRNAs) in OA are widely elucidated. Herein, we intend to explore the function and molecular mechanism of lncRNA KCNQ1OT1 in CHON-001 cells.

METHODS

Relative expression of KCNQ1OT1, miR-126-5p and TRPS1 was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability was examined by MTT assay. The migratory ability of chondrocytes was assessed by transwell assay. Western blot was used to determine relative protein expression of collagen II, MMP13 and TRPS1. Dual-luciferase reporter (DLR) assay was applied to test the target of lncRNA KCNQ1OT1 or miR-126-5p.

RESULTS

Relative expression of KCNQ1OT1 and TRPS1 was reduced, whereas miR-126-5p was augmented in cartilage tissues of post-traumatic OA patients compared to those of subjects without post-traumatic OA. Increased KCNQ1OT1 or decreased miR-126-5p enhanced cell viability and migration, and repressed extracellular matrix (ECM) degradation in CHON-001 cells. MiR-126-5p was the downstream target of KCNQ1OT1, and it could directly target TRPS1. There was an inverse correlation between KCNQ1OT1 and miR-126-5p or between miR-126-5p and TRPS1. Meantime, there was a positive correlation between KCNQ1OT1 and TRPS1. The promoting impacts of KCNQ1OT1 on cell viability and migration as well as the suppressive impact of KCNQ1OT1 on ECM degradation were partially abolished by miR-126-5p overexpression or TRPS1 knockdown in CHON-001 cells.

CONCLUSIONS

Overexpression of KCNQ1OT1 attenuates the development of OA by sponging miR-126-5p to target TRPS1. Our findings may provide a possible therapeutic strategy for human OA in clinic.

The function of lncRNAs in the pathogenesis of osteoarthritis

Osteoarthritis (OA), one of the most common motor system disorders, is a degenerative disease involving progressive joint destruction caused by a variety of factors. At present, OA has become the fourth most common cause of disability in the world. However, the pathogenesis of OA is complex and has not yet been clarified. Long non-coding RNA (lncRNA) refers to a group of RNAs more than 200 nucleotides in length with limited protein-coding potential, which have a wide range of biological functions including regulating transcriptional patterns and protein activity, as well as binding to form endogenous small interference RNAs (siRNAs) and natural microRNA (miRNA) molecular sponges. In recent years, a large number of lncRNAs have been found to be differentially expressed in a variety of pathological processes of OA, including extracellular matrix (ECM) degradation, synovial inflammation, chondrocyte apoptosis, and angiogenesis. Obviously, lncRNAs play important roles in regulating gene expression, maintaining the phenotype of cartilage and synovial cells, and the stability of the intra-articular environment. This article reviews the results of the latest research into the role of lncRNAs in a variety of pathological processes of OA, in order to provide a new direction for the study of OA pathogenesis and a new target for prevention and treatment. Cite this article: Bone Joint Res 2021;10(2):122-133.

RNA Sequencing Reveals LINC00167 as a Potential Diagnosis Biomarker for Primary Osteoarthritis: A Multi-Stage Study

Objectives

Given the roles played by lncRNA in human diseases and the high incidence of OA, this study investigated the pivotal pathways involved in the disease and identified potential biomarkers for OA diagnosis.

Methods

We first performed an exploration of RNA-sequencing in peripheral blood leukocytes from six subjects (3 OA and 3 healthy controls). Promising candidate lncRNAs were evaluated in first stage validation using a GEO dataset (GSE114007) of 38 subjects (20 OA and 18 healthy controls), followed by a second stage validation using quantitative PCR analysis with 101 subjects (67 OA and 34 controls). The third stage investigated the potential value of validated lncRNA in the early diagnosis of OA in peripheral blood leukocytes from a total of 120 participants (60 cases and 60 controls).

Results

The dataset identified a total of 1,380 up-regulated and 719 down-regulated mRNAs and 5,743 up-regulated and 7,384 down-regulated lncRNAs. The up-regulated DEGs were mainly enriched in the extracellular matrix, while the down-regulated DEGs were mainly enriched in the IL-17 and wnt signaling pathways. 18 overlapping candidate lncRNAs survived after first-stage validation. 3 hub lncRNAs were selected for the second validation stage and qualified in an external sample, and lncRNA LINC00167 was further confirmed with a similar result (down-expressed in both stages). Receiver operating characteristic analysis showed that LINC00167 can distinguish OA cases from healthy controls with a high area under the curve of 0.879 (95%CI: 0.819, 0.938; P < 0.001), with a sensitivity of 80.7% and specificity of 83.5%.

Conclusion

The expression profile of OA was identified and critical pathways were elucidated by an integrated approach to RNA-seq from easily accessible blood. LINC00167 may serve as a potential early diagnosis marker for OA in clinical practice. The detailed mechanism of action of this lncRNA requires further elucidation in future studies.

Neohesperidin Ameliorates Steroid-Induced Osteonecrosis of the Femoral Head by Inhibiting the Histone Modification of lncRNA HOTAIR

Background

Neohesperidin (NH) and lncRNA HOTAIR (HOTAIR) could regulate osteoclastic and osteogenic differentiation. This study aimed to explore whether HOTAIR-mediated osteogenic differentiation was regulated by NH.

Methods

Steroid-induced osteonecrosis of the femoral head (SONFH) mice model was established. Histopathological changes in mouse osteonecrosis tissues were detected by hematoxylin-eosin staining. Bone marrow stromal cells (BMSCs) were isolated from healthy mice bone marrow samples by Ficoll density gradient and identified by flow cytometry. After treating the BMSCs with NH and dexamethasone or transfecting with HOTAIR overexpression plasmids and siHOTAIR, histone modification of HOTAIR, the cell viability, osteogenic differentiation, and adipogenic differentiation were detected by chromatin immunoprecipitation, MTT, Alizarin Red and Oil Red O staining, respectively. The expressions of HOTAIR and differentiation-related factors in the BMSCs were detected by RT-qPCR and Western blot.

Results

HOTAIR was highly expressed in SONFH model mice. NH ameliorated histopathological changes in the model mice, but the effect was reversed by overexpressed HOTAIR. NH increased viability of BMSCs and the H3K27me3 occupancy of HOTAIR, but decreased the expression and the H3K4me3 occupancy of HOTAIR. HOTAIR expression was down-regulated in BMSCs after osteogenic differentiation but was up-regulated after adipogenic differentiation. HOTAIR overexpression inhibited osteogenic differentiation and the expressions of RUNX2, OCN, and ALP, but increased adipogenic differentiation and the expressions of LPL and PPARr in BMSCs; moreover, the opposite results were observed in siHOTAIR.

Conclusion

NH ameliorated SONFH by inhibiting the histone modifications of HOTAIR.

Autophagy dysfunction may be involved in the pathogenesis of ankylosing spondylitis

The present study aimed to investigate the expression and significance of the mRNA of genes associated with autophagy and long non-coding RNA (lncRNA) GAS5 in peripheral blood mononuclear cells (PBMCs) of patients with ankylosing spondylitis (AS). The mRNA levels of microtubule-associated protein light chain 3 (LC3), Beclin1, autophagy-related gene (ATG)3, ATG5, ATG12, ATG 16 ligand 1 (ATG16L1) and lncRNA growth arrest-specific 5 (GAS5) in PBMCs from 60 patients with AS and 30 healthy controls (HC) were examined by reverse transcription-quantitative PCR. The correlations between the levels of LC3, Beclin1, ATG3, ATG5, ATG12 and ATG16L1 mRNA as well as lncRNA GAS5 levels with disease activity and laboratory parameters in patients with AS were determined by Spearman correlation analysis. In addition, the diagnostic value of lncRNA GAS5 for AS was explored through establishing a receiver operating characteristic (ROC) curve. The results indicated that, compared to the HCs, patients with AS had lower expression levels of LC3, ATG5, ATG12, ATG16L1 and lncRNA GAS5 in their PBMCs. Compared with those in patients with inactive AS, the levels of ATG5 and ATG12 were lower than those in patients with active AS. Of note, ATG5 and ATG12 mRNA levels were negatively correlated with disease activity indexes. lncRNA GAS5 was positively correlated with the expression of Beclin1, ATG3, ATG5, ATG12 and ATG16L1. The area under the ROC curve for the use of lncRNA GAS5 expression to diagnose AS was 0.808 with a 95% CI of 0.714-0.902. In conclusion, patients with AS had decreased expression of genes associated with autophagy and lncRNA GAS5. The extent of the reduction in ATG5 and ATG12 expression levels in patients with AS was correlated with the disease severity and activity. Furthermore, lncRNA GAS5 was a diagnostic indicator of AS.

The Fibroblast-Like Synoviocyte Derived Exosomal Long Non-coding RNA H19 Alleviates Osteoarthritis Progression Through the miR-106b-5p/TIMP2 Axis

Osteoarthritis (OA) is a common degenerative joint disease that affects people worldwide. The interaction between fibroblast-like synoviocytes (FLSs) and chondrocytes may play a vital role in OA disease pathology. However, the underlying mechanisms by which FLSs exert regulatory effects on chondrocytes still need to be elucidated. Exosomes, small membrane vesicles secreted from living cells, are known to play a variety of roles in mediating cell-to-cell communication through the transferring of biological components such as non-coding RNAs and proteins. Here, we investigate the cellular processes of chondrocytes regulated by FLS-derived exosomes and the mechanisms of action underlying the functions of exosomes in OA pathogenesis. We observed that exosome-mediated cartilage repair was characterized by increased cell viability and migration as well as alleviated matrix degradation. Using chondrocyte cultures, the enhanced cellular proliferation and migration during exosome-mediated cartilage repair was linked to the exosomal lncRNA H19-mediated regulation of the miR-106b-5p/TIMP2 axis. Transfection of miR-106-5p mimics in chondrocytes significantly decreased cell proliferation and migration, promoted matrix degradation characterized by elevated MMP13 and ADAMTS5 expression, and reduced the expression of COL2A1 and ACAN in chondrocytes. Furthermore, we found that TIMP2 was directly regulated by miR-106-5p. Co-transfections of miR-106-5p mimics and TIMP2 resulted in higher levels of COL2A1 and ACAN, but lower levels of MMP13 and ADAMTS5. Together, these observations demonstrated that the lncRNA H19 may promote chondrocyte proliferation and migration and inhibit matrix degradation in OA possibly by targeting the miR-106b-5p/TIMP2 axis. In the future, H19 may serve as a potential therapeutic target for the treatment of OA.

Differential long non-coding RNA expression profiles in the peripheral blood and CD4+ T cells of patients with active rheumatoid arthritis

The human transcriptome is primarily composed of long non-coding RNAs (lncRNAs), which are key regulatory molecules of multiple biological processes. In the present study, the expression profiles of lncRNAs in the peripheral blood and CD4⁺ T cells of patients with active rheumatoid arthritis (RA) were determined. Based on the expression profiles, 493 lncRNAs and 374 mRNAs were identified to be differentially expressed in the peripheral blood of active RA patients and healthy donors. Further verification of lncRNAs was performed using reverse transcription-quantitative (RT-q) PCR analysis of peripheral blood from 5 healthy donors and 5 patients with active RA and 14 additional differentially expressed genes were identified. CD4⁺ T cells in peripheral blood from 12 patients with active RA and 8 healthy donors were isolated using magnetic beads and qPCR was used to assess differentially expressed lncRNAs. The results suggested that 7 lncRNAs were upregulated and 2 were downregulated. The results indicated that these 9 lncRNAs may be involved in the pathogenesis of RA. An increased ratio of Th17: T-regulatory (Treg) cells was also observed. It may be hypothesized that LncRNAs serve important roles in the differentiation of CD4⁺ T cells. Receiver operating characteristic curve analysis suggested that these 9 lncRNAs are of potential clinical diagnostic value for RA. Pearson correlation analysis indicated that the correlation coefficient between Ensembl transcript (ENST)00000569543 and complement C4 was 0.623 (P<0.05), and that between ENST00000420096 and anti-cyclic citrullinated peptide antibody or disease activity evaluation score, the correlation coefficient was 0.662 and 0.605, respectively (P<0.05 for each). In conclusion, the results of the present study suggest a possible role of lncRNAs in the differentiation of CD4⁺ T cells and the pathogenesis of RA, as well as the potential value as diagnostic biomarkers for active RA.

Noncoding RNAs: New regulatory code in chondrocyte apoptosis and autophagy

Osteoarthritis (OA) is a bone and joint disease characterized by progressive cartilage degradation. In the face of global trends of population aging, OA is expected to become the fourth most common disabling disease by 2020. Nevertheless, the detailed pathogenesis of OA has not yet been elucidated. Noncoding RNAs (ncRNAs), including long noncoding RNAs, microRNAs, and circular RNAs, do not encode proteins but have recently emerged as important regulators of apoptosis and autophagy of chondrocytes, thereby highlighting a potential role in chondrocyte injury leading to OA onset and progression. We here review recent findings on these regulatory roles of ncRNAs to provide new directions for research on the pathogenesis of OA and offer new therapeutic targets for prevention and treatment. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA in Disease and Development > RNA in Development.

Editorial focus: understanding off-target effects as the key to successful RNAi therapy

With the first RNA interference (RNAi) drug (ONPATTRO (patisiran)) on the market, we witness the RNAi therapy field reaching a critical turning point, when further improvements in drug candidate design and delivery pipelines should enable fast delivery of novel life changing treatments to patients. Nevertheless, ignoring parallel development of RNAi dedicated in vitro pharmacological profiling aiming to identify undesirable off-target activity may slow down or halt progress in the RNAi field. Since academic research is currently fueling the RNAi development pipeline with new therapeutic options, the objective of this article is to briefly summarize the basics of RNAi therapy, as well as to discuss how to translate basic research into better understanding of related drug candidate safety profiles early in the process.

Significance of expression of lncRNA-ATB in serum of patients with cholestatic liver disease

BACKGROUND

Cholestatic liver disease (CSLD) refers to a collection of liver diseases that can cause cholestasis. The etiology of CSLD is complex, the pathogenesis needs to be elucidated, and there is still a lack of effective treatment. Over the past decade, there has been a deep understanding of many aspects of CSLD, which provides more effective means for its accurate diagnosis and treatment. However, many problems are still pending, and further research is urgently needed.

AIM

To observe the difference of serum lncRNA-ATB levels between patients with intrahepatic cholestasis and normal people, and to explore the correlation between the changes of serum lncRNA-ATB and disease condition and prognosis in patients with intrahepatic cholestasis.

METHODS

Seventy-five patients with intrahepatic cholestasis of different etiologies and 30 healthy controls were included. The expression of lncRNA-ATB in serum samples of the above subjects was detected by qRT-PCR. The levels of lncRNA-ATB between normal controls and patients with cholestasis and between patients with different degrees of cholestasis were analyzed. Linear correlation analysis was used to analyze the correlation between the changes of lncRNA-ATB and clinical biochemical indicators, and receiver operating characteristic curve analysis was performed to analyze the clinical significance of the changes of lncRNA-ATB in judging the condition of intrahepatic cholestasis.

RESULTS

Compared with the healthy control group, lncRNA-ATB increased significantly in the serum of patients with intrahepatic cholestasis (P < 0.05). There was no significant difference in the expression of lncRNA-ATB between patients with cholestatic liver disease caused by different etiologies and and between patients with different courses of cholestasis (P > 0.05). Serum lncRNA-ATB decreased with the aggravation of cholestasis (P < 0.001). There was a negative correlation between lncRNA-ATB and total bile acid (r = -0.627, P < 0.001). The area under the curve of lncRNA-ATB in the diagnosis of cholestasis liver disease was 0.856 (95%CI: 0.809-0.904, P < 0.001), with a sensitivity of 81.42% and specificity of 73.45%.

CONCLUSION

The level of lncRNA-ATB in serum of patients with intrahepatic cholestasis liver disease is significantly increased, and it decreases with the aggravation of cholestasis. The expression level of LncRNA-ATB is expected to be a biomarker for judging the condition and prognosis of patients with intrahepatic cholestasis.