Digoxin ameliorates joint inflammatory microenvironment by downregulating synovial macrophage M1-like-polarization and its-derived exosomal miR-146b-5p/Usp3&Sox5 axis

Therapeutic potential of SOX family transcription factors in osteoarthritis

BACKGROUND

As the worldwide population ages, osteoarthritis has significantly increased. This musculoskeletal condition has become a pressing global health issue and thus, prevention and treatment of osteoarthritis have become the primary focus of domestic and international research. Scholarly investigations of the molecular mechanisms that are related to the occurrence and development of osteoarthritis have shed light on the pathological causes of this condition to a certain extent, providing a foundation for its prevention and treatment. However, further research is necessary to fully understand the critical role of the transcription factor SOX9 in chondrocyte differentiation and the development of osteoarthritis. As a result, there has been widespread interest in SOX transcription factors. While SOX9 has been utilized as a biomarker to indicate the occurrence and prognosis of osteoarthritis, investigations into other members of the SOX family and the development of targeted treatments around SOX9 are still required.

PURPOSE

This article considers the impact of the SOX protein on the development and inhibition of osteoarthritis and highlights the need for therapeutic approaches targeting SOX9, as supported by existing research.

RESULTS

SOX9 can contribute to the process of osteoarthritis through acetylation and ubiquitination modifications. The regulation of the WNT signalling pathway, Nrf2/ARE signalling pathway, NF-κB signalling pathway and SOX9 is implicated in the emergence of osteoarthritis. Non-coding RNA may play a role in the onset and progression of osteoarthritis by modulating various SOX family members, including SOX2, SOX4, SOX5, SOX6, SOX8, SOX9 and SOX11.

CONCLUSION

SOX9 has the capability of mitigating the onset and progression of osteoarthritis through means such as medication therapy, stem cell therapy, recombinant adeno-associated virus (rAAV) vector therapy, physical therapy and other approaches.

Macrophages-derived small extracellular vesicles regulate chondrocyte proliferation and affect osteoarthritis progression via upregulating Osteopontin expression

Small extracellular vesicles (sEVs) are considered promising gene-delivery vehicles for the treatment of osteoarthritis (OA). This study aimed to explore the molecular mechanism by which M2 macrophage-derived sEVs (M2-sEVs) modulate chondrocyte proliferation and apoptosis, thereby affecting OA progression. M2 macrophages were successfully induced, and M2-sEVs were successfully isolated. The sEVs were small vesicles with diameters ranging from 50 to 150 nm. The exosomal markers, including CD9, CD63, and CD81, were highly expressed, whereas the negative marker calnexin was absent in M2-sEVs. M2-sEVs effectively alleviated OA tissue and chondrocyte damage in both in vivo and in vitro models, evidenced by reduced rat knee joint injury, increased chondrocyte viability, and decreased chondrocyte apoptosis and extracellular matrix (ECM) degradation. Furthermore, M2-sEVs decreased the levels of pro-inflammatory cytokines IL-6 and TNF-α. Osteopontin (OPN) was upregulated within rats with OA and IL-1β-induced chondrocytes. Silencing of OPN exacerbated IL-1β-induced chondrocyte damage and partially abrogated the therapeutic effects of M2-sEVs. Additionally, M2-sEVs enhanced OPN expression and activated CD44 and the PI3K/AKT signaling pathway. In conclusion, M2-sEVs promoted OPN expression to improve knee joint tissue damage in rats with OA and chondrocyte damage. This protective effect of M2-sEVs might be associated with the activation of CD44 and the PI3K/AKT signaling.

The communication role of extracellular vesicles in the osteoarthritis microenvironment

Osteoarthritis (OA) is the most common degenerative joint disease worldwide, characterized by synovial inflammation, cartilage loss, and reactive hyperplasia of subchondral bone, affecting the quality of life of hundreds of millions of people. However, the molecular mechanisms underlying the occurrence and progression of OA remain unclear, and there is no therapy can substantially interrupt or reverse the destructive process of OA. More insight into the pathogenesis of OA may result in innovative therapeutics. The OA microenvironment plays a pivotal role in the development and progression of OA, which encompasses chondrocytes, adipocytes, synovial fibroblasts, endothelial cells, and immune cells. Extracellular vesicles (EVs) have emerged as a novel form of intercellular communication, mediating the transfer of a range of bioactive molecules to create a specific microenvironment. Recent studies have reported that the cargos of EVs play a crucial role in the pathogenesis of OA, including noncoding RNAs (ncRNAs), proteins, and lipids. This review systematically analyzes and summarizes the biological characteristics and functionalities of EVs derived from diverse cellular sources, especially how EVs mediate communication between different cells in the OA microenvironment, with a view to providing new insights into the pathogenesis of OA.

Exosomal non-coding RNAs in the regulation of bone metabolism homeostasis: Molecular mechanism and therapeutic potential

Bone metabolism is a dynamic balance between bone formation and absorption regulated by osteoblasts/osteoclasts. Bone metabolic disorders can lead to metabolic bone disease. Osteoporosis (OP), osteoarthritis (OA) and femoral head necrosis (ONFH) are common metabolic bone diseases. At present, the treatment of metabolic bone disease is still mainly to relieve pain and improve joint function. However, surgical treatment does not apply to the vast majority of high-risk groups, including postmenopausal women, patients with diabetes, cirrhosis, etc. Exosomes (Exos) are nanoscale membrane vesicles that are released by almost all cells. Exos are rich in a variety of bioactive substances, such as non-coding RNAs, nucleic acids, proteins and lipids. In view of the structure of Exos, it can protect the biologically active molecules can be smoothly delivered to the target cells and involved in the regulation of cell function. In this review, we focus on the regulation mechanism and function of bone homeostasis mediated by exosomal ncRNAs (Exos-ncRNAs), including macrophage polarization, autophagy, angiogenesis, signal transduction and competing endogenous RNA (ceRNA). We summarized the therapeutic strategies and potential drugs of Exos-ncRNAs in metabolic bone disease. Moreover, we discussed the shortcomings and potential research directions of Exos as carrier to deliver ncRNAs to play a role.

Mapping the knowledge landscape: A bibliometric analysis of exosome research in osteoarthritis (2004-2023)

Exosomes have emerged as a crucial focus in advancing the diagnosis and treatment of osteoarthritis (OA). However, there are limited bibliometric studies on this topic. This study aimed to delineate the literature landscape on exosomes in OA, identifying global research trends and key areas. We utilised the Web of Science Core Collection to retrieve articles published from 2004 to 2023. Our analysis included 456 publications across 671 institutions from 40 countries/regions. Publication volume, citations, and emerging research foci and trends were examined. Our results reveal a consistently increased interest in exosomes related to OA over the past two decades. Prominent institutions contributing to this research include Shanghai Jiao Tong University and Shenzhen University. The leading journal for these publications is the International Journal of Molecular Sciences, with Stem Cell Research & Therapy being the most frequently co-cited journal. Notable scholars in this field are Li Duan, Yujie Liang, Xiao Xu, and Wei Seong Toh, with Shipin Zhang emerging as the most co-cited author. The principal research themes were elucidating how exosomes contribute to OA pathology and developing novel therapeutic approaches. Research hotspots and new trends are linked to terms such as "cartilage," "mesenchymal stem cell," "miRNA," "treatment," and "biomarkers." This comprehensive analysis offers valuable insights into the prevailing scientific discourse, pivotal topics, and potential future directions. It could serve as a foundational reference for researchers exploring exosomes and their utility in OA diagnostics and therapeutics.

Ubiquitination and deubiquitination: Implications for the pathogenesis and treatment of osteoarthritis

Osteoarthritis (OA) is a degenerative disease that affects multiple cells and associated extracellular matrix (ECM). Chondrocytes and chondroextracellular matrix together constitute articular cartilage tissue. Any factors that affect the activity of chondrocytes and destroy the metabolic balance of the chondrocyte ECM will lead to the inability of articular cartilage to perform normal functions. The articular subchondral bone and articular cartilage must be coordinated to resist enough friction and mechanical stress, so the articular subchondral bone lesion will aggravate the articular cartilage defect and vice versa. Synoviocytes, including fibroblast-like synoviocytes (FLSs) and synovial macrophages at the joint, are also important factors that cause low-grade chronic progressive inflammation of OA. Regulation of phenotype transformation of synovial macrophages has become another possible target for the clinical treatment of OA. Ubiquitination and deubiquitination are the main post-translational protein modification pathways in the human body, which are widely involved in multiple signaling pathways and physiological processes. Naturally, they also play a very important regulatory role in the occurrence and development of OA. These effects are summarized in this review, including (A) regulating the aging and apoptosis of chondrocytes, FLSs and osteoblasts; (B) regulation of ECM degradation; (C) regulation of macrophage phenotypic transformation; (D) modulation of skeletal muscle and adipose tissues. Ubiquitination targeting drugs for OA treatment are also listed. Depending on the high efficiency of ubiquitination and deubiquitination, understanding OA-related ubiquitination pathways can help design more efficient drugs to treat OA and provide more potential targets for clinical treatment. The Translational Potential of This Article. In this paper, the ubiquitination-related pathways in osteoarthritis (OA), including aging, apoptosis and autophagy in chondrocytes, osteoblasts, FLSs and macrophages were investigated. In particular, several ubiquitination-related targets are expected to be effective approaches for OA clinical treatment. In addition, in the process of OA occurrence and development, the complex relationship between the local joint area and other tissues including skeletal muscle and adipose tissue is also discussed. These myokines and adipokines from musculoskeletal tissues are all expected to become efficient targets for OA treatment apart from the joint itself. In addition, those myokines secreted by cardiovascular tissues would show potential therapeutic effects as well. What if altering the contents for these ubiquitination-related targets in the serum through exercise will provide a new idea for OA therapy or prevent OA from deteriorating continuously?

Nanozyme-enhanced injectable hyaluronic acid-based hydrogel for the treatment of osteoarthritis

The progression of osteoarthritis (OA) is dramatically accelerated by excessive reactive oxygen species (ROS)-induced apoptosis of chondrocytes and the inflammatory response of synovial macrophages. In this study, we developed an injectable hydrogel with a catalase-mimicking nanozyme activity as a therapeutic agent for OA. In vitro experiments confirmed that the HA and peroxide-mimetic nanoenzyme-enhanced hydrogel, containing ε-polylysine/Mn1.8Co1.2O4 (ε-PLE/MnCoO) nanoparticles, continuously eliminated ROS and inflammatory cytokines while promoting the polarization of inflammatory macrophages (M1 phenotype) towards anti-inflammatory macrophages (M2 phenotype) in dysfunctional microenvironments. When used for intraarticular injections in OA models, the nanoenzyme-enhanced hydrogel effectively reduced oxidative stress by scavenging ROS and regulating the immune microenvironment. It resulted in a subsequent reduction in the expression of inflammatory factors, including MMP-13, TNF-α, IL-1β, and iNOS in both the synovium and joint fluid. Moreover, cartilage repair was enhanced by the promotion of COL-2 and SOX-9 expression in the cartilage tissue, whereas osteophyte formation in OA was reduced. This study introduced an innovative treatment strategy for the clinical management of OA, demonstrating its significant potential for application in treating OA.

Cell volume regulation modulates macrophage-related inflammatory responses via JAK/STAT signaling pathways

Cell volume as a characteristic of changes in response to external environmental cues has been shown to control the fate of stem cells. However, its influence on macrophage behavior and macrophage-mediated inflammatory responses have rarely been explored. Herein, through mediating the volume of macrophages by adding polyethylene glycol (PEG), we demonstrated the feasibility of fine-tuning cell volume to regulate macrophage polarization towards anti-inflammatory phenotypes, thereby enabling to reverse macrophage-mediated inflammation response. Specifically, lower the volume of primary macrophages can induce both resting macrophages (M0) and stimulated pro-inflammatory macrophages (M1) to up-regulate the expression of anti-inflammatory factors and down-regulate pro-inflammatory factors. Further mechanistic investigation revealed that macrophage polarization resulting from changing cell volume might be mediated by JAK/STAT signaling pathway evidenced by the transcription sequencing analysis. We further propose to apply this strategy for the treatment of arthritis via direct introduction of PEG into the joint cavity to modulate synovial macrophage-related inflammation. Our preliminary results verified the credibility and effectiveness of this treatment evidenced by the significant inhibition of cartilage destruction and synovitis at early stage. In general, our results suggest that cell volume can be a biophysical regulatory factor to control macrophage polarization and potentially medicate inflammatory response, thereby providing a potential facile and effective therapy for modulating macrophage mediated inflammatory responses. STATEMENT OF SIGNIFICANCE: Cell volume has recently been recognized as a significantly important biophysical signal in regulating cellular functionalities and even steering cell fate. Herein, through mediating the volume of macrophages by adding polyethylene glycol (PEG), we demonstrated the feasibility of fine-tuning cell volume to induce M1 pro-inflammatory macrophages to polarize towards anti-inflammatory M2 phenotype, and this immunomodulatory effect may be mediated by the JAK/STAT signaling pathway. We also proposed the feasible applications of this PEG-induced volume regulation approach towards the treatment of osteoarthritis (OA), wherein our preliminary results implied an effective alleviation of early synovitis. Our study on macrophage polarization mediated by cell volume may open up new pathways for immune regulation through microenvironmental biophysical clues.

Endothelial cells-derived exosomes-based hydrogel improved tendinous repair via anti-inflammatory and tissue regeneration-promoting properties

Tendon injuries are common orthopedic ailments with a challenging healing trajectory, especially in cases like the Achilles tendon afflictions. The healing trajectory of tendon injuries is often suboptimal, leading to scar formation and functional impairment due to the inherent low metabolic activity and vascularization of tendon tissue. As pressing is needed for effective interventions, efforts are made to explore biomaterials to augment tendon healing. However, tissue engineering approaches face hurdles in optimizing tissue scaffolds and nanomedical strategies. To navigate these challenges, an injectable hydrogel amalgamated with human umbilical vein endothelial cells-derived exosomes (HUVECs-Exos) was prepared and named H-Exos-gel in this study, aiming to enhance tendon repair. In our research involving a model of Achilles tendon injuries in 60 rats, we investigated the efficacy of H-Exos-gel through histological assessments performed at 2 and 4 weeks and behavioral assessments conducted at the 4-week mark revealed its ability to enhance the Achilles tendon's mechanical strength, regulate inflammation and facilitate tendon regeneration and functional recovery. Mechanically, the H-Exos-gel modulated the cellular behaviors of macrophages and tendon-derived stem cells (TDSCs) by inhibiting inflammation-related pathways and promoting proliferation-related pathways. Our findings delineate that the H-Exos-gel epitomizes a viable bioactive medium for tendon healing, heralding a promising avenue for the clinical amelioration of tendon injuries.

USP3: Key deubiquitylation enzyme in human diseases

Ubiquitination and deubiquitylation are pivotal posttranslational modifications essential for regulating cellular protein homeostasis and are implicated in the development of human diseases. Ubiquitin-specific protease 3 (USP3), a member of the ubiquitin-specific protease family, serves as a key deubiquitylation enzyme, playing a critical role in diverse cellular processes including the DNA damage response, cell cycle regulation, carcinogenesis, tumor cell proliferation, migration, and invasion. Despite notable research efforts, our current understanding of the intricate and context-dependent regulatory networks governing USP3 remains incomplete. This review aims to comprehensively synthesize existing published works on USP3, elucidating its multifaceted roles, functions, and regulatory mechanisms, while offering insights for future investigations. By delving into the complexities of USP3, this review strives to provide a foundation for a more nuanced understanding of its specific roles in various cellular processes. Furthermore, the exploration of USP3's regulatory networks may uncover novel therapeutic strategies targeting this enzyme in diverse human diseases, thereby holding promising clinical implications. Overall, an in-depth comprehension of USP3's functions and regulatory pathways is crucial for advancing our knowledge and developing targeted therapeutic approaches for human diseases.

A quick and innovative pipeline for producing chondrocyte-homing peptide-modified extracellular vesicles by three-dimensional dynamic culture of hADSCs spheroids to modulate the fate of remaining ear chondrocytes in the M1 macrophage-infiltrated microenvironment

BACKGROUND

Extracellular vesicles (EVs) derived from human adipose-derived mesenchymal stem cells (hADSCs) have shown great therapeutic potential in plastic and reconstructive surgery. However, the limited production and functional molecule loading of EVs hinder their clinical translation. Traditional two-dimensional culture of hADSCs results in stemness loss and cellular senescence, which is unfavorable for the production and functional molecule loading of EVs. Recent advances in regenerative medicine advocate for the use of three-dimensional culture of hADSCs to produce EVs, as it more accurately simulates their physiological state. Moreover, the successful application of EVs in tissue engineering relies on the targeted delivery of EVs to cells within biomaterial scaffolds.

METHODS AND RESULTS

The hADSCs spheroids and hADSCs gelatin methacrylate (GelMA) microspheres are utilized to produce three-dimensional cultured EVs, corresponding to hADSCs spheroids-EVs and hADSCs microspheres-EVs respectively. hADSCs spheroids-EVs demonstrate excellent production and functional molecule loading compared with hADSCs microspheres-EVs. The upregulation of eight miRNAs (i.e. hsa-miR-486-5p, hsa-miR-423-5p, hsa-miR-92a-3p, hsa-miR-122-5p, hsa-miR-223-3p, hsa-miR-320a, hsa-miR-126-3p, and hsa-miR-25-3p) and the downregulation of hsa-miR-146b-5p within hADSCs spheroids-EVs show the potential of improving the fate of remaining ear chondrocytes and promoting cartilage formation probably through integrated regulatory mechanisms. Additionally, a quick and innovative pipeline is developed for isolating chondrocyte homing peptide-modified EVs (CHP-EVs) from three-dimensional dynamic cultures of hADSCs spheroids. CHP-EVs are produced by genetically fusing a CHP at the N-terminus of the exosomal surface protein LAMP2B. The CHP + LAMP2B-transfected hADSCs spheroids were cultured with wave motion to promote the secretion of CHP-EVs. A harvesting method is used to enable the time-dependent collection of CHP-EVs. The pipeline is easy to set up and quick to use for the isolation of CHP-EVs. Compared with nontagged EVs, CHP-EVs penetrate the biomaterial scaffolds and specifically deliver the therapeutic miRNAs to the remaining ear chondrocytes. Functionally, CHP-EVs show a major effect on promoting cell proliferation, reducing cell apoptosis and enhancing cartilage formation in remaining ear chondrocytes in the M1 macrophage-infiltrated microenvironment.

CONCLUSIONS

In summary, an innovative pipeline is developed to obtain CHP-EVs from three-dimensional dynamic culture of hADSCs spheroids. This pipeline can be customized to increase EVs production and functional molecule loading, which meets the requirements for regulating remaining ear chondrocyte fate in the M1 macrophage-infiltrated microenvironment.

Ubiquitin specific peptidase 3: an emerging deubiquitinase that regulates physiology and diseases

Proteins are the keystone for the execution of various life activities, and the maintenance of protein normalization is crucial for organisms. Ubiquitination, as a post-transcriptional modification, is widely present in organisms, and it relies on the sophisticated ubiquitin-proteasome (UPS) system that controls protein quality and modulates protein lifespan. Deubiquitinases (DUBs) counteract ubiquitination and are essential for the maintenance of homeostasis. Ubiquitin specific peptidase 3 (USP3) is a member of the DUBs that has received increasing attention in recent years. USP3 is a novel chromatin modifier that tightly regulates the DNA damage response (DDR) and maintains genome integrity. Meanwhile, USP3 acts as a key regulator of inflammatory vesicles and sustains the normal operation of the innate immune system. In addition, USP3 is aberrantly expressed in a wide range of cancers, such as gastric cancer, glioblastoma and neuroblastoma, implicating that USP3 could be an effective target for targeted therapies. In this review, we retrace all the current researches of USP3, describe the structure of USP3, elucidate its functions in DNA damage, immune and inflammatory responses and the cell cycle, and summarize the important role of USP3 in multiple cancers and diseases.

Extracellular Vesicles in Infrapatellar Fat Pad from Osteoarthritis Patients Impair Cartilage Metabolism and Induce Senescence

Infrapatellar fat pad (IPFP) is closely associated with the development and progression of knee osteoarthritis (OA), but the underlying mechanism remains unclear. Here, it is find that IPFP from OA patients can secret small extracellular vesicles (sEVs) and deliver them into articular chondrocytes. Inhibition the release of endogenous osteoarthritic IPFP-sEVs by GW4869 significantly alleviated IPFP-sEVs-induced cartilage destruction. Functional assays in vitro demonstrated that IPFP-sEVs significantly promoted chondrocyte extracellular matrix (ECM) catabolism and induced cellular senescence. It is further demonstrated that IPFP-sEVs induced ECM degradation in human and mice cartilage explants and aggravated the progression of experimental OA in mice. Mechanistically, highly enriched let-7b-5p and let-7c-5p in IPFP-sEVs are essential to mediate detrimental effects by directly decreasing senescence negative regulator, lamin B receptor (LBR). Notably, intra-articular injection of antagomirs inhibiting let-7b-5p and let-7c-5p in mice increased LBR expression, suppressed chondrocyte senescence and ameliorated the progression of experimental OA model. This study uncovers the function and mechanism of the IPFP-sEVs in the progression of OA. Targeting IPFP-sEVs cargoes of let-7b-5p and let-7c-5p can provide a potential strategy for OA therapy.

The role of exosomes and their enhancement strategies in the treatment of osteoarthritis

With the increasingly prominent problem of population aging, osteoarthritis (OA), which is closely related to aging, has become a serious illness affecting the lives and health of elderly individuals. However, effective treatments are still lacking. OA is typically considered a low-grade inflammatory state. The inflammatory infiltration of macrophages, neutrophils, T cells, and other cells is common in diseased joints. These cells create the inflammatory environment of OA and are involved in the onset and progression of the disease. Exosomes, a type of complex vesicle containing abundant RNA molecules and proteins, play a crucial role in the physiological and pathological processes of an organism. In comparison to other therapeutic methods such as stem cells, exosomes have distinct advantages of precise targeting and low immunogenicity. Moreover, research and techniques related to exosomes are more mature, indicating a promising future in disease treatment. Many studies have shown that the impact of exosomes on the inflammatory microenvironment directly or indirectly leads to the occurrence of various diseases. Furthermore, exosomes can be helpful in the management of illnesses. This article provides a comprehensive review and update on the research of exosomes, a type of extracellular vesicle, in the treatment of OA by modulating the inflammatory microenvironment. It also combines innovative studies on the modification of exosomes. In general, the application of exosomes in the treatment of OA has been validated, and the introduction of modified exosome technology holds potential for enhancing its therapeutic efficacy.

Circulating exosomal has-miR-24-3p and has-miR-128-3p reflect early efficacy of sublingual immunotherapy in allergic rhinitis

OBJECTIVE

Sublingual immunotherapy (SLIT) can improve the symptoms of allergic rhinitis (AR) and modify its natural course, but its effectiveness varies among individuals. This study aims to analyze miRNAs from serum exosomes and evaluate their predictive values for the early response of SLIT in AR.

METHODS

RNA sequencing was performed to investigate the differential expressions of serum exosomal miRNAs between ineffective and effective AR patients who treated with SLIT. The identified candidate miRNAs were validated in two independent cohorts, and the predictive capabilities of these miRNAs and alterations of their expression levels between pre- and 1 year post-SLIT were evaluated.

RESULTS

The serum exosome-derived miRNA profiles were significantly different between the effective and ineffective groups. The five most up-regulated and down-regulated miRNAs were verified in the first validation cohort, and the results demonstrated that serum exosomal has-miR-24-3p and has-miR-206 were reduced, while has-miR-128-3p was increased in the effective group compared to the ineffective group (P < 0.05). Additionally, the receiver operating characteristic (ROC) curves revealed that serum levels of has-miR-24-3p and has-miR-128-3p displayed potential values for predicting the early efficacy of SLIT (P < 0.05). In the second validation cohort, it was observed that the baseline levels of serum exosomal has-miR-24-3p were significantly lower, while has-miR-128-3p levels were significantly higher in the effective group compared to the ineffective group (P < 0.05). After 1 year of SLIT, there was a significant decrease in serum exosomal levels of has-miR-24-3p compared to baseline. On the other hand, effective patients showed a notable increase in serum exosomal levels of has-miR-128-3p (P < 0.05).

CONCLUSION

Serum exosome-derived miRNAs have the potential to impact the efficacy of SLIT in AR patients. Among them, serum exosomal has-miR-24-3p and has-miR-128-3p show promise as biomarkers for predicting the early effectiveness of SLIT and monitoring therapeutic outcomes.

Exploring molecular mechanisms underlying the pathophysiological association between knee osteoarthritis and sarcopenia

Objectives

Accumulating evidence indicates a strong link between knee osteoarthritis (KOA) and sarcopenia. However, the mechanisms involved have not yet been elucidated. This study primarily aims to explore the molecular mechanisms that explain the connection between these 2 disorders.

Methods

The gene expression profiles for KOA and sarcopenia were obtained from the Gene Expression Omnibus database, specifically from GSE55235, GSE169077, and GSE1408. Various bioinformatics techniques were employed to identify and analyze common differentially expressed genes (DEGs) across the 3 datasets. The techniques involved the analysis of Gene Ontology and pathways to enhance understanding, examining protein-protein interaction (PPI) networks, and identifying hub genes. In addition, we constructed the network of interactions between transcription factors (TFs) and genes, the co-regulatory network of TFs and miRNAs for hub genes, and predicted potential drugs.

Results

In total, 14 common DEGs were found between KOA and sarcopenia. Detailed information on biological processes and signaling pathways of common DEGs was obtained through enrichment analysis. After performing PPI network analysis, we discovered 4 hub genes (FOXO3, BCL6, CDKN1A, and CEBPB). Subsequently, we developed coregulatory networks for these hub genes involving TF-gene and TF-miRNA interactions. Finally, we identified 10 potential chemical compounds.

Conclusions

By conducting bioinformatics analysis, our study has successfully identified common gene interaction networks between KOA and sarcopenia. The potential of these findings to offer revolutionary understanding into the common development of these 2 conditions could lead to the identification of valuable targets for therapy.

Membrane vesicles from Lactobacillus johnsonii delay osteoarthritis progression via modulating macrophage glutamine synthetase/mTORC1 axis

AIMS

The manipulation of macrophage recruitment and their shift in the M1/M2 ratio is a promising approach to mitigate osteoarthritis (OA). Nevertheless, the current clinical medication available for OA is only palliative and may result in undesirable outcomes. Hence, it is urgent to explore alternative disease-modifying drug supplement that are both safer and more effective in OA treatment, like probiotic and probiotic-derived membrane vesicles.

METHODS

The synovial inflammation and cartilage damage in collagenase-induced OA (CIOA) mice were observed using haematoxylin and eosin, saffron O-solid green and immunohistochemical staining. Bipedal balance test and open field test were conducted to determine the effectiveness of L. johnsonii-derived membrane vesicles (LJ-MVs) in reducing joint pain of CIOA mice. Additionally, Transwell, western blot, and immunological testing were used to examine the effect of LJ-MVs on macrophage migration and reprogramming. Furthermore, a 4D label-free proteomic analysis of LJ-MVs and their parent bacterium was performed, and the glutamine synthetase (GS)/mTORC1 axis in macrophage was verified by western blot.

RESULTS

L. johnsonii and its membrane vesicles, LJ-MVs, exhibit a novel ability to mitigate inflammation, cartilage damage, and pain associated with OA. This is achieved by their ability to impede macrophage migration, M1-like polarization, and inflammatory mediators secretion, while simultaneously promoting the M2/M1 ratio in synovial macrophages. The mechanism underlying this effect involves the modulation of macrophage GS/mTORC1 pathway, at least partially.

SIGNIFICANCE

Owing to their probiotic derivation, LJ-MVs will be a more dependable and potent disease-modifying drugs for the prevention and therapy of OA in the long run.

Elucidating the role of ubiquitination and deubiquitination in osteoarthritis progression

Osteoarthritis is non-inflammatory degenerative joint arthritis, which exacerbates disability in elder persons. The molecular mechanisms of osteoarthritis are elusive. Ubiquitination, one type of post-translational modifications, has been demonstrated to accelerate or ameliorate the development and progression of osteoarthritis via targeting specific proteins for ubiquitination and determining protein stability and localization. Ubiquitination process can be reversed by a class of deubiquitinases via deubiquitination. In this review, we summarize the current knowledge regarding the multifaceted role of E3 ubiquitin ligases in the pathogenesis of osteoarthritis. We also describe the molecular insight of deubiquitinases into osteoarthritis processes. Moreover, we highlight the multiple compounds that target E3 ubiquitin ligases or deubiquitinases to influence osteoarthritis progression. We discuss the challenge and future perspectives via modulation of E3 ubiquitin ligases and deubiquitinases expression for enhancement of the therapeutic efficacy in osteoarthritis patients. We conclude that modulating ubiquitination and deubiquitination could alleviate the osteoarthritis pathogenesis to achieve the better treatment outcomes in osteoarthritis patients.

Serum exosomal miR-146a-3p associates with disease severity and efficacy of sublingual immunotherapy in allergic rhinitis

BACKGROUND

Sublingual immunotherapy (SLIT) is an effective treatment for allergic rhinitis (AR), but its efficacy is variable among individuals. This study aimed to characterize serum exosome-derived microRNAs (miRNAs) and evaluate their abilities in predicting the efficacy of SLIT in AR.

METHODS

RNA sequencing was performed to explore differentially expressed exosomal miRNAs in serum exosomes between AR patients and healthy controls (HCs). Sequencing analysis results were verified in an independent cohort, and the correlations between the levels of exosome-derived miRNAs and disease severity were evaluated. The most promising miRNAs were further tested in two AR cohorts treated with SLIT to assess their abilities in predicting short and long-term efficacy, respectively.

RESULTS

The exosome-derived miRNAs profiling in the AR group was significantly different from the HC group, and differentially expressed genes were enriched and clustered in pathways such as PI3K-Akt and ErbB signalling pathways. The top three most significant miRNAs were verified by reverse transcription-polymerase chain reaction (qRT-PCR), and results showed that miR-146a-3p levels were significantly elevated in the AR group and correlated with the total and specific gE levels, the visual analogue scale of the total nasal symptom score (all p < 0.05). Further data in the first validation cohort suggested that miR-146a-3p levels were significantly downregulated in the effective group, and logistic regression showed that miR-146a-3p levels were associated with the short-term efficacy of SLIT(p < 0.05). The receiver operating characteristic (ROC) curve showed that miR-146a-3p could early predict SLIT efficacy (AUC = 0.669, p = 0.047). In the second validation cohort, miR-146a-3p levels were also decreased in the effective group and the ROC curve further confirmed its reliable accuracy in predicting the long-term efficacy of SLIT in AR patients (AUC = 0.749, p < 0.001).

CONCLUSION

Serum exosome-derived miRNAs may be involved in the development of AR and associated with its disease severity. Serum exosome-derived miR-146a-3p seems to be a novel biomarker for predicting the short and long-term efficacies of SLIT in AR patients.

Targeting macrophage polarization as a promising therapeutic strategy for the treatment of osteoarthritis

Osteoarthritis (OA) is a chronic osteoarthropathy characterized by the progressive degeneration of articular cartilage and synovial inflammation. Early OA clinical treatments involve intra-articular injection of glucocorticoids, oral acetaminophen and non-steroidal anti-inflammatory drugs (NSAIDs), which are used for anti-inflammation and pain relief. However, long-term use of these agents will lead to inevitable side effects, even aggravate cartilage loss. At present, there are no disease-modifying OA drugs (DMOADs) yet approved by regulatory agencies. Polarization regulation of synovial macrophages is a new target for OA treatment. Inhibiting M1 polarization and promoting M2 polarization of synovial macrophages can alleviate synovial inflammation, relieve joint pain and inhibit articular cartilage degradation, which is a promising strategy for OA treatment. In this study, we describe the molecular mechanisms of macrophage polarization and its key role in the development of OA. Subsequently, we summarize the latest progress of strategies for OA treatment through macrophage reprogramming, including small molecule compounds (conventional western medicine and synthetic compounds, monomer compounds of traditional Chinese medicine), biomacromolecules, metal/metal oxides, cells, and cell derivatives, and interprets the molecular mechanisms, hoping to provide some information for DMOADs development.

Naturally derived injectable hydrogels with ROS-scavenging property to protect transplanted stem cell bioactivity for osteoarthritic cartilage repair

Intra-articular injection of adipose mesenchymal stem cells (ADSCs) is a potential alternative to the treatment of osteoarthritis (OA) and has aroused great interest of clinical researchers. However, the hostile microenvironment in the joint cavity, characterized by reactive oxygen species (ROS) accumulation and excessive inflammation, disturbs the bioactivity of the transplanted stem cells. The (-)-epigallocatechin-3-O-gallate (EGCG), a green tea catechin, has attracted the researchers' attention owing to its powerful ROS-scavenging and antioxidant properties. In this study, to avoid rapid degradation and/or depletion of EGCG, we prepare a long-lasting injectable hydrogel by EGCG and hyaluronic acid (HA). The naturally derived hydrogels with excellent biocompatibility and durable retention time can capture the redundant ROS continuously and efficiently, thus protecting ADSCs from ROS-mediated death and bioactivity inhibition, including cell survival, proliferation and chondrogenic differentiation. Intra-articular injection of this ADSCs loaded hydrogel significantly induced synovial macrophages polarization to M2 phenotype, decreased pro-inflammatory cytokines (e.g., IL-1β, MMP-13, and TNF-α) expression, promoted cartilage matrix formation, and repaired cartilage destruction in OA. This stem cell-protected hydrogel delivery strategy showed superior efficacy than ADSCs delivering or EGCG-HA injection singly, which providing a potential alternative strategy for OA management.