MicroRNA-410-3p modulates chondrocyte apoptosis and inflammation by targeting high mobility group box 1 (HMGB1) in an osteoarthritis mouse model

The Role of Alarmins in the Pathogenesis of Rheumatoid Arthritis, Osteoarthritis, and Psoriasis

Alarmins are immune-activating factors released after cellular injury or death. By secreting alarmins, cells can interact with immune cells and induce a variety of inflammatory responses. The broad family of alarmins involves several members, such as high-mobility group box 1, S100 proteins, interleukin-33, and heat shock proteins, among others. Studies have found that the concentrations and expression profiles of alarmins are altered in immune-mediated diseases. Furthermore, they are involved in the pathogenesis of inflammatory conditions. The aim of this narrative review is to present the current evidence on the role of alarmins in rheumatoid arthritis, osteoarthritis, and psoriasis. We discuss their potential involvement in mechanisms underlying the progression of these diseases and whether they could become therapeutic targets. Moreover, we summarize the impact of pharmacological agents used in the treatment of these diseases on the expression of alarmins.

Advancements in tissue engineering for articular cartilage regeneration

Articular cartilage injury is a prevalent clinical condition resulting from trauma, tumors, infection, osteoarthritis, and other factors. The intrinsic lack of blood vessels, nerves, and lymphatic vessels within cartilage tissue severely limits its self-regenerative capacity after injury. Current treatment options, such as conservative drug therapy and joint replacement, have inherent limitations. Achieving perfect regeneration and repair of articular cartilage remains an ongoing challenge in the field of regenerative medicine. Tissue engineering has emerged as a key focus in articular cartilage injury research, aiming to utilize cultured and expanded tissue cells combined with suitable scaffold materials to create viable, functional tissues. This review article encompasses the latest advancements in seed cells, scaffolds, and cytokines. Additionally, the role of stimulatory factors including cytokines and growth factors, genetic engineering techniques, biophysical stimulation, and bioreactor systems, as well as the role of scaffolding materials including natural scaffolds, synthetic scaffolds, and nanostructured scaffolds in the regeneration of cartilage tissues are discussed. Finally, we also outline the signaling pathways involved in cartilage regeneration. Our review provides valuable insights for scholars to address the complex problem of cartilage regeneration and repair.

Knockdown of DAPK1 inhibits IL-1β-induced inflammation and cartilage degradation in human chondrocytes by modulating the PEDF-mediated NF-κB and NLRP3 inflammasome pathway

Osteoarthritis (OA) is a common joint disease that is characterized by inflammation and cartilage degradation. Death-associated protein kinase 1 (DAPK1) is a multi-domain serine/threonine kinase and has been reported to be involved in the progression of OA. However, its role and mechanism in OA remain unclear. Here, we found the expression of DAPK1 in OA cartilage tissues was higher than that in normal cartilage tissues. The expression of DAPK1 in chondrocytes was up-regulated by IL-1β. Knockdown of DAPK1 promoted cell viability and anti-apoptotic protein expression, while it inhibited the apoptosis rate and pro-apoptotic protein expressions in IL-1β-induced chondrocytes. In addition, DAPK1 inhibition reduced the levels of inflammatory cytokines and expressions of matrix metalloproteinases (MMPs), and increased the expressions of collagen II and aggrecan. The data of mechanistic investigation indicated that the expression of pigment epithelium-derived factor (PEDF) was positively regulated by DAPK1. Overexpression of PEDF attenuated the effects of DAPK1 knockdown on IL-1β-induced cell viability, apoptosis, inflammation, and cartilage degradation. Furthermore, PEDF overexpression restored the activity of the NF-κB pathway and NLRP3 inflammasome after DAPK1 knockdown. Collectively, down-regulation of DAPK1 inhibited IL-1β-induced inflammation and cartilage degradation via the PEDF-mediated NF-κB and NLRP3 inflammasome pathways.

Catapol attenuates the aseptic inflammatory response to hepatic I/R injury in vivo and in vitro by inhibiting the HMGB1/TLR-4/NF-κB signaling pathway via the microRNA-410-3p

BACKGROUND

Hepatic ischemia-reperfusion (I/R) injury involves inflammatory necrosis of liver cells as a significant pathological mechanism. Catapol possesses anti-inflammatory activity that is extracted from the traditional Chinese medicine, Rehmannia glutinosa.

METHODS

The liver function and histopathology, Oxidative stress, and aseptic inflammatory responses were assessed in vivo, and the strongest dose group was selected. For mechanism, the expression of miR-410-3p, HMGB1, and TLR-4/NF-κB signaling pathways was detected. The dual luciferase assay can verify the targeting relationship between miR-410-3p and HMGB1. Knockdown of miR-410-3p in L02 cells is applied in interference experiments.

RESULTS

CAT pre-treatment significantly decreased the liver function markers alanine and aspartate aminotransferases and reduced the areas of hemorrhage and necrosis induced by hepatic I/R injury. Additionally, it reduced the aseptic inflammatory response and oxidative stress, with the strongest protective effect observed in the high-dose CAT group. Mechanistically, CAT downregulates HMGB1, inhibits TLR-4/NF-κB signaling pathway activation, and reduces inflammatory cytokines TNF-α, and IL-1β. In addition, the I/R-induced downregulation of microRNA-410-3p was inhibited by CAT pre-treatment in vivo and in vitro. HMGB1 was identified as a potential target of microRNA-410-3p using a dual-luciferase reporter assay. Knockdown of microRNA-410-3p abolished the inhibitory effect of CAT on HMGB1, p-NF-κB, and p-IκB-α protein expression.

CONCLUSIONS

Our study showed that CAT pre-treatment has a protective effect against hepatic I/R injury in rats. Specifically, CAT attenuates the aseptic inflammatory response to hepatic I/R injury in vivo and in vitro by inhibiting the HMGB1/TLR-4/NF-κB signaling pathway via the microRNA-410-3p.

Cinnamaldehyde Induces the Expression of MicroRNA-1285-5p and MicroRNA-140-5p in Chondrocytes to Ameliorate the Apoptosis and Inflammatory Response

OBJECTIVE

Cinnamaldehyde (CA) is an active ingredient of Wenyang Tongluo capsule. This study was performed to investigate the function of CA on human chondrocytes.

DESIGN

Different doses of CA were used to treat C28/I2 cells, which were stimulated by interleukin-1β (IL-1β), and then the viability and apoptosis of the cells were examined by cell counting kit-8 and flow cytometry. Interleukin-6 (IL-6), interleukin-20 (IL-20), and tumor necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent assay. Quantitative real-time reverse transcriptase polymerase chain reaction was performed to measure miR-1285-5p, miR-140-5p, IL-20, and high-mobility group box 1 (HMGB1) messenger RNA (mRNA) expression. Western blot assay was performed to detect IL-20, HMGB1, IKBα, phospho-IKBα, IKKα/β, and phospho-IKKα/β expression. Moreover, the relationships between miR-1285-5p and IL-20, as well as miR-140-5p and HMGB1, were validated by dual-luciferase reporter assay.

RESULTS

CA promoted the viability and inhibited the apoptosis of C28/I2 cells stimulated by IL-1β and repressed IL-6, IL-20, and TNF-α levels. CA increased miR-1285-5p and miR-140-5p expression levels. MiR-1285-5p and miR-140-5p promoted the viability and inhibited the apoptosis and inflammation of C28/I2 cells. IL-20 was a target gene of miR-1285-5p, and HMGB1 was a target gene of miR-140-5p. Overexpression of IL-20 or HMGB1 could reverse the effect of CA on C28/I2 cells treated with IL-1β. In addition, HMGB1 increased phospho-IKBα and phospho-IKKα/β expression in IL-1β- and CA-treated C28/I2 cells.

CONCLUSIONS

CA protects chondrocytes via regulating miR-1285-5p/IL-20 axis and miR-140-5p/HMGB1/nuclear factor kappa B pathway.

Selenomethionine Antagonized microRNAs Involved in Apoptosis of Rat Articular Cartilage Induced by T-2 Toxin

T-2 toxin and selenium deficiency are considered important etiologies of Kashin-Beck disease (KBD), although the exact mechanism is still unclear. To identify differentially expressed microRNAs (DE-miRNAs) in the articular cartilage of rats exposed to T-2 toxin and selenomethionine (SeMet) supplementation, thirty-six 4-week-old Sprague Dawley rats were divided into a control group (gavaged with 4% anhydrous ethanol), a T-2 group (gavaged with 100 ng/g·bw/day T-2 toxin), and a T-2 + SeMet group (gavaged with 100 ng/g·bw/day T-2 toxin and 0.5 mg/kg·bw/day SeMet), respectively. Toluidine blue staining was performed to detect the pathological changes of articular cartilage. Three rats per group were randomly selected for high-throughput sequencing of articular cartilage. Target genes of DE-miRNAs were predicted using miRanda and RNAhybrid databases, and the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway were enriched. The network map of miRNA-target genes was constructed using Cytoscape software. The expression profiles of miRNAs associated with KBD were obtained from the Gene Expression Omnibus database. Additionally, the DE-miRNAs were selected for real-time quantitative PCR (RT-qPCR) verification. Toluidine blue staining demonstrated that T-2 toxin damaged articular cartilage and SeMet effectively alleviated articular cartilage lesions. A total of 50 DE-miRNAs (28 upregulated and 22 downregulated) in the T-2 group vs. the control group, 18 DE-miRNAs (6 upregulated and 12 downregulated) in the T-2 + SeMet group vs. the control group, and 25 DE-miRNAs (5 upregulated and 20 downregulated) in the T-2 + SeMet group vs. the T-2 group were identified. Enrichment analysis showed the target genes of DE-miRNAs were associated with apoptosis, and in the MAPK and TGF-β signaling pathways in the T-2 group vs. the control group. However, the pathway of apoptosis was not significant in the T-2 + SeMet group vs. the control group. These results indicated that T-2 toxin induced apoptosis, whereas SeMet supplementation antagonized apoptosis. Apoptosis and autophagy occurred simultaneously in the T-2 + SeMet group vs. T-2 group, and autophagy may inhibit apoptosis to protect cartilage. Compared with the GSE186593 dataset, the evidence of miR-133a-3p involved in apoptosis was more abundant. The results of RT-qPCR validation were consistent with RNA sequencing results. Our findings suggested that apoptosis was involved in articular cartilage lesions induced by T-2 toxin, whereas SeMet supplementation antagonized apoptosis, and that miR-133a-3p most probably played a central role in the apoptosis process.

The role of apoptosis in the pathogenesis of osteoarthritis

PURPOSE

Apoptosis is an important physiological process, making a great difference to development and tissue homeostasis. Osteoarthritis (OA) is a chronic joint disease characterized by degeneration and destruction of articular cartilage and bone hyperplasia. This purpose of this study is to provide an updated review of the role of apoptosis in the pathogenesis of osteoarthritis.

METHODS

A comprehensive review of the literature on osteoarthritis and apoptosis was performed, which mainly focused on the regulatory factors and signaling pathways associated with chondrocyte apoptosis in osteoarthritis and other pathogenic mechanisms involved in chondrocyte apoptosis.

RESULTS

Inflammatory mediators such as reactive oxygen species (ROS), nitric oxide (NO), IL-1β, tumor necrosis factor-α (TNF-α), and Fas are closely related to chondrocyte apoptosis. NF-κB signaling pathway, Wnt signaling pathway, and Notch signaling pathway activate proteins and gene targets that promote or inhibit the progression of osteoarthritis disease, including chondrocyte apoptosis and ECM degradation. Long non-coding RNAs (LncRNAs) and microRNAs (microRNAs) have gradually replaced single and localized research methods and become the main research approaches. In addition, the relationship between cellular senescence, autophagy, and apoptosis was also briefly explained.

CONCLUSION

This review offers a better molecular delineation of apoptotic processes that may help in designing new therapeutic options for OA treatment.

The Nrf2/HMGB1/NF-κB axis modulates chondrocyte apoptosis and extracellular matrix degradation in osteoarthritis

Osteoarthritis (OA) is a degenerative or posttraumatic condition of the joints. In OA chondrocytes, Nrf2 functions as a stress response regulator with antioxidant and anti-inflammatory effects. This study aims to investigate the role of Nrf2 and its downstream pathway in the development of osteoarthritis. IL-1β treatment suppresses Nrf2, aggrecan, and COL2A1 levels and cell viability but promotes apoptosis in chondrocytes. IL-1β stimulation induces cell apoptosis, upregulates the mRNA expression of inflammatory factors, decreases aggrecan, COL2A1, and Bcl-2 levels but increases ADAMTS-5, ADAMTS-4, MMP13, cleaved caspase 3, and BAX levels, and promotes p65 phosphorylation. Nrf2 overexpression exerts opposite effects on IL-1β-treated chondrocytes, as demonstrated by the significant attenuation of IL-1β-induced changes in chondrocytes. By binding to the HMGB1 promoter region, Nrf2 suppresses HMGB1 expression. Similar to Nrf2 overexpression, HMGB1 knockdown also attenuates IL-1β-induced changes in chondrocytes. Notably, under IL-1β stimulation, the effects of Nrf2 overexpression or tert-butylhydroquinone (TBHQ, an activator of Nrf2) on apoptosis, inflammatory factor expression, ECM and apoptosis, and NF-κB pathway activity in chondrocytes are remarkably reversed by HMGB1 overexpression or recombinant HMGB1 (rHMGB1). Similarly, rHMGB1 could partially counteract the curative effect of TBHQ on OA damage in mice. In OA cartilage tissue samples, the level of Nrf2 is lower, while the levels of HMGB1, apoptotic, and inflammatory factors are increased compared to normal cartilage tissue samples. In conclusion, for the first time, the Nrf2/HMGB1 axis was found to modulate apoptosis, ECM degradation, inflammation and activation of NF-κB signaling in chondrocytes and OA mice.

Silencing miR-146a-5p Protects against Injury-Induced Osteoarthritis in Mice

Osteoarthritis (OA), the most prevalent joint disease and the leading cause of disability, remains an incurable disease largely because the etiology and pathogenesis underlying this degenerative process are poorly understood. Low-grade inflammation within joints is a well-established factor that disturbs joint homeostasis and leads to an imbalance between anabolic and catabolic processes in articular cartilage; however, the complexity of the network between inflammatory factors that often involves positive and negative feedback loops makes current anti-cytokine therapy ineffective. MicroRNAs (miRNAs) have emerged as key regulators to control inflammation, and aberrant miRNAs expression has recently been linked to OA pathophysiology. In the present study, we characterized transcriptomic profiles of miRNAs in primary murine articular chondrocytes in response to a proinflammatory cytokine, IL-1β, and identified miR-146a-5p as the most responsive miRNA to IL-1β. miR-146a-5p was also found to be upregulated in human OA cartilage. We further demonstrated that knockdown of miR-146a-5p antagonized IL-1β-mediated inflammatory responses and IL-1β-induced catabolism in vitro, and silencing of miR-146a in chondrocytes ameliorated articular cartilage destruction and reduced OA-evoked pain in an injury-induced murine OA model. Moreover, parallel RNA sequencing revealed that differentially expressed genes in response to IL-1β were enriched in pathways related to inflammatory processes, cartilage matrix homeostasis, and cell metabolism. Bioinformatic analyses of putative miR-146a-5p gene targets and following prediction of protein-protein interactions suggest a functional role of miR-146a-5p in mediating inflammatory processes and regulation of cartilage homeostasis. Our genetic and transcriptomic data define a crucial role of miR-146a-5p in OA pathogenesis and implicate modulation of miR-146a-5p in articular chondrocytes as a potential therapeutic strategy to alleviate OA.

MicroRNAs miR-584-5p and miR-425-3p Are Up-Regulated in Plasma of Colorectal Cancer (CRC) Patients: Targeting with Inhibitor Peptide Nucleic Acids Is Associated with Induction of Apoptosis in Colon Cancer Cell Lines

Liquid biopsy has dramatically changed cancer management in the last decade; however, despite the huge number of miRNA signatures available for diagnostic or prognostic purposes, it is still unclear if dysregulated miRNAs in the bloodstream could be used to develop miRNA-based therapeutic approaches. In one author's previous work, nine miRNAs were found to be dysregulated in early-stage colon cancer (CRC) patients by NGS analysis followed by RT-dd-PCR validation. In the present study, the biological effects of the targeting of the most relevant dysregulated miRNAs with anti-miRNA peptide nucleic acids (PNAs) were verified, and their anticancer activity in terms of apoptosis induction was evaluated. Our data demonstrate that targeting bloodstream up-regulated miRNAs using anti-miRNA PNAs leads to the down-regulation of target miRNAs associated with inhibition of the activation of the pro-apoptotic pathway in CRC cellular models. Moreover, very high percentages of apoptotic cells were found when the anti-miRNA PNAs were associated with other pro-apoptotic agents, such as sulforaphane (SFN). The presented data sustain the idea that the targeting of miRNAs up-regulated in the bloodstream with a known role in tumor pathology might be a tool for the design of protocols for anti-tumor therapy based on miRNA-targeting molecules.

Muscle-Specific Micro-Ribonucleic Acids miR-1-3p, miR-133a-3p, and miR-133b Reflect Muscle Regeneration After Single-Dose Zoledronic Acid Following Rotator Cuff Repair in a Rodent Chronic Defect Model

BACKGROUND

Zoledronic acid improves bone microarchitecture and biomechanical properties after chronic rotator cuff repair (RCR) in rats. Besides the positive effects of zoledronic acid on bone mineral density and bone microarchitecture, bisphosphonates have positive effects on skeletal muscle function.

PURPOSES/HYPOTHESIS

The purposes of this study were to (1) longitudinally evaluate circulating bone- and muscle-specific serum micro-ribonucleic acids (miRNAs) and (2) investigate supraspinatus muscle tissue after tenotomy and delayed RCR in a rat model. It was hypothesized that zoledronic acid would improve muscle regeneration after chronic RCR in rats.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 34 male Sprague-Dawley rats underwent unilateral (left) supraspinatus tenotomy (time point 1) with delayed transosseous RCR after 3 weeks (time point 2). All rats were sacrificed 8 weeks after RCR (time point 3). Animals were randomly assigned to 2 groups. One day after RCR, the control group was given 1 mL of subcutaneous saline solution, and the intervention group was treated with a subcutaneous single-dose of 100 µg/kg body weight of zoledronic acid. All 34 study animals underwent miRNA analysis at all 3 time points. In 4 animals of each group, histological analyses as well as gene expression analyses were conducted.

RESULTS

Circulating miRNAs showed significantly different expressions between both study groups. In the control group, a significant downregulation was observed for muscle-specific miR-1-3p (P = .004), miR-133a-3p (P < .001), and miR-133b (P < .001). Histological analyses showed significantly higher rates of regenerating myofibers on the operated side (left) of both study groups compared with the nonoperated side (right; P = .002). On the nonoperated side, significantly higher rates of regenerating myofibers were observed in the intervention group compared with the control group (P = .031). The myofiber cross-sectional area revealed significantly smaller myofibers on both sides within the intervention group compared with both sides of the control group (P < .001). Within the intervention group, significantly higher expression levels of muscle development/regeneration marker genes embryonal Myosin heavy chain (P = .017) and neonatal Myosin heavy chain (P = .016) were observed on the nonoperated side compared with the operated side.

CONCLUSION

An adjuvant single-dose of zoledronic acid after RCR in a chronic defect model in rats led to significant differences in bone- and muscle-specific miRNA levels. Therefore, miR-1-3p, miR-133a-3p, and miR-133b might be used as biomarkers for muscle regeneration after RCR.

CLINICAL RELEVANCE

Adjuvant treatment with zoledronic acid may improve muscle regeneration after chronic RCR in humans, thus counteracting fatty muscle infiltration and atrophy.

A review of non-coding RNA related to NF-κB signaling pathway in the pathogenesis of osteoarthritis

Osteoarthritis (OA), often called as "wear and tear" arthritis, is the most common form of degenerative joint arthritis and is a leading cause of disability. The nuclear factor-kappaB (NF-κB) transcription factor has long been recognized as a disease-contributing factor for OA. More and more evidences show that targeting NF-κB signaling could offer novel potential therapeutic options for OA damage and reduce the risk of potential side-effects. In recent years, it has been shown that non-coding RNAs(ncRNAs) can trigger the expression of an array of genes and widely activate NF-κB signaling pathway, which induces destruction of the articular joint, leading to OA onset and progression. In this review, we discuss the involvement of NF-κB in OA pathogenesis and how ncRNAs attend and affect OA incidence and evolution, offering novel potential therapeutic options for OA treatment.

miR-294 and miR-410 Negatively Regulate Tnfa, Arginine Transporter Cat1/2, and Nos2 mRNAs in Murine Macrophages Infected with Leishmania amazonensis

MicroRNAs are small non-coding RNAs that regulate cellular processes by the post-transcriptional regulation of gene expression, including immune responses. The shift in the miRNA profiling of murine macrophages infected with Leishmania amazonensis can change inflammatory response and metabolism. L-arginine availability and its conversion into nitric oxide by nitric oxide synthase 2 (Nos2) or ornithine (a polyamine precursor) by arginase 1/2 regulate macrophage microbicidal activity. This work aimed to evaluate the function of miR-294, miR-301b, and miR-410 during early C57BL/6 bone marrow-derived macrophage infection with L. amazonensis. We observed an upregulation of miR-294 and miR-410 at 4 h of infection, but the levels of miR-301b were not modified. This profile was not observed in LPS-stimulated macrophages. We also observed decreased levels of those miRNAs target genes during infection, such as Cationic amino acid transporters 1 (Cat1/Slc7a1), Cat2/Slc7a22 and Nos2; genes were upregulated in LPS stimuli. The functional inhibition of miR-294 led to the upregulation of Cat2 and Tnfa and the dysregulation of Nos2, while miR-410 increased Cat1 levels. miR-294 inhibition reduced the number of amastigotes per infected macrophage, showing a reduction in the parasite growth inside the macrophage. These data identified miR-294 and miR-410 biomarkers for a potential regulator in the inflammatory profiles of microphages mediated by L. amazonensis infection. This research provides novel insights into immune dysfunction contributing to infection outcomes and suggests the use of the antagomiRs/inhibitors of miR-294 and miR-410 as new therapeutic strategies to modulate inflammation and to decrease parasitism.

Unraveling the Signaling Secretome of Platelet-Rich Plasma: Towards a Better Understanding of Its Therapeutic Potential in Knee Osteoarthritis

Platelets and their secretory products play an important role in determining the balance between tissue repair and tissue damage. To obtain novel insights into the molecular composition of platelet-rich plasma (PRP) and contextualize them in knee osteoarthritis (OA), two different plasma formulations, namely PRP and platelet-poor plasma (PPP), were prepared from six healthy donors following a biobank-automated protocol. Inter-donor differences were analyzed, and pools were created before performing multiplexing protein arrays. In addition, PRP and PPP were prepared from six patients following our in-house protocols. Supernatants from PRP and PPP were harvested one hour after calcium chloride activation. Multiplexing protein arrays were performed in parallel for all plasma formulations. Results were normalized to fold change in relation to PPP and examined using Ingenuity Pathway Analysis Software. Bioinformatic predictions showed that PRPs constitute a signaling system with interrelated networks of inflammatory and angiogenic proteins, including but not limited to interleukin-6 and -8 (IL-6, IL-8), insulin like growth factor 1 (IGF-1), transforming growth factor beta, (TGF-b), and vascular endothelial growth factor (VEGF) signaling, underlying biological actions. Predictions of canonical systems activated with PRP molecules include various inflammatory pathways, including high-mobility group box protein (HMGB1) and interleukin 17 (IL-17) signaling, neuroinflammation, and nuclear factor-kappa b (NF-κB) pathways. Eventually, according to these predictions and OA evolving knowledge, selected PRP formulations should be tailored to modulate different inflammatory phenotypes, i.e., meta-inflammation, inflame-aging or posttraumatic inflammatory osteoarthritis. However, further research to discriminate the peculiarities of autologous versus allogeneic formulations and their effects on the various OA inflammatory phenotypes is needed to foster PRPs.

Crosstalk Among circRNA/lncRNA, miRNA, and mRNA in Osteoarthritis

Osteoarthritis (OA) is a joint disease that is pervasive in life, and the incidence and mortality of OA are increasing, causing many adverse effects on people's life. Therefore, it is very vital to identify new biomarkers and therapeutic targets in the clinical diagnosis and treatment of OA. ncRNA is a nonprotein-coding RNA that does not translate into proteins but participates in protein translation. At the RNA level, it can perform biological functions. Many studies have found that miRNA, lncRNA, and circRNA are closely related to the course of OA and play important regulatory roles in transcription, post-transcription, and post-translation, which can be used as biological targets for the prevention, diagnosis, and treatment of OA. In this review, we summarized and described the various roles of different types of miRNA, lncRNA, and circRNA in OA, the roles of different lncRNA/circRNA-miRNA-mRNA axis in OA, and the possible prospects of these ncRNAs in clinical application.

Anesthetics mediated the immunomodulatory effects via regulation of TLR signaling

Anesthetics have been widely used in surgery and found to suppress inflammatory injury and affect the outcomes of the surgery and diseases. In contrast, anesthetics are also found to induce neuronal injury and inflammation. However, the immune-modulation mechanism of anesthetics is still not clear. Recent studies have shown that the immune-modulation of anesthetics is associated with the regulation of toll-like receptor (TLR)-mediated signaling. Moreover, the regulation of anesthetics in TLR signaling is related to modulations of non-coding RNAs (nc RNAs). Consistently, nc RNAs are mainly divided into micro RNAs (miRs) and long non-coding RNAs (lnc RNAs), which have been found to exert regulatory effects on the immune system. In this review, we summarize the immunomodulatory functions of the widely used anesthetic agents, which are associated with regulation of TLR signaling. In addition, we also focus on the roles of nc RNAs induced by anesthetics in regulations of TLR signaling.

The non-coding RNA interactome in joint health and disease

Non-coding RNAs have distinct regulatory roles in the pathogenesis of joint diseases including osteoarthritis (OA) and rheumatoid arthritis (RA). As the amount of high-throughput profiling studies and mechanistic investigations of microRNAs, long non-coding RNAs and circular RNAs in joint tissues and biofluids has increased, data have emerged that suggest complex interactions among non-coding RNAs that are often overlooked as critical regulators of gene expression. Identifying these non-coding RNAs and their interactions is useful for understanding both joint health and disease. Non-coding RNAs regulate signalling pathways and biological processes that are important for normal joint development but, when dysregulated, can contribute to disease. The specific expression profiles of non-coding RNAs in various disease states support their roles as promising candidate biomarkers, mediators of pathogenic mechanisms and potential therapeutic targets. This Review synthesizes literature published in the past 2 years on the role of non-coding RNAs in OA and RA with a focus on inflammation, cell death, cell proliferation and extracellular matrix dysregulation. Research to date makes it apparent that 'non-coding' does not mean 'non-essential' and that non-coding RNAs are important parts of a complex interactome that underlies OA and RA.

The Role of microRNAs in Pulp Inflammation

The dental pulp can be affected by thermal, physical, chemical, and bacterial phenomena that stimulate the inflammatory response. The pulp tissue produces an immunological, cellular, and vascular reaction in an attempt to defend itself and resolve the affected tissue. The expression of different microRNAs during pulp inflammation has been previously documented. MicroRNAs (miRNAs) are endogenous small molecules involved in the transcription of genes that regulate the immune system and the inflammatory response. They are present in cellular and physiological functions, as well as in the pathogenesis of human diseases, becoming potential biomarkers for diagnosis, prognosis, monitoring, and safety. Previous studies have evidenced the different roles played by miRNAs in proinflammatory, anti-inflammatory, and immunological phenomena in the dental pulp, highlighting specific key functions of pulp pathology. This systematized review aims to provide an understanding of the role of the different microRNAs detected in the pulp and their effects on the expression of the different target genes that are involved during pulp inflammation.