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Annals of the Rheumatic Diseases Nov 2023Prior studies noted that chondrocyte SIRT6 activity is repressed in older chondrocytes rendering cells susceptible to catabolic signalling events implicated in...
OBJECTIVES
Prior studies noted that chondrocyte SIRT6 activity is repressed in older chondrocytes rendering cells susceptible to catabolic signalling events implicated in osteoarthritis (OA). This study aimed to define the effect of deficiency on the development of post-traumatic and age-associated OA in mice.
METHODS
Male cartilage-specific -deficient mice and intact controls underwent destabilisation of the medial meniscus (DMM) or sham surgery at 16 weeks of age and OA severity was analysed at 6 and 10 weeks postsurgery. Age-associated OA was assessed in mice aged 12 and 18 months of age. OA severity was analysed by micro-CT, histomorphometry and scoring of articular cartilage structure, toluidine blue staining and osteophyte formation. SIRT6-regulated pathways were analysed in human chondrocytes by RNA-sequencing, qRT-PCR and immunoblotting.
RESULTS
deficient mice displayed enhanced DMM-induced OA severity and accelerated age-associated OA when compared with controls, characterised by increased cartilage damage, osteophyte formation and subchondral bone sclerosis. In chondrocytes, RNA-sequencing revealed that depletion significantly repressed cartilage extracellular matrix (eg, ) and anabolic growth factor (eg, insulin-like growth factor-1 ()) gene expression. Gain-of-function and loss-of-function studies in chondrocytes demonstrated that SIRT6 depletion attenuated, whereas adenoviral overexpression or MDL-800-induced activation promoted IGF-1 signalling by increasing Akt phosphorylation.
CONCLUSIONS
SIRT6 deficiency increases post-traumatic and age-associated OA severity in vivo. SIRT6 profoundly regulated the pro-anabolic and pro-survival IGF-1/Akt signalling pathway and suggests that preserving the SIRT6/IGF-1/Akt axis may be necessary to protect cartilage from injury-associated or age-associated OA. Targeted therapies aimed at increasing SIRT6 function could represent a novel strategy to slow or stop OA.
Topics: Male; Animals; Mice; Humans; Aged; Insulin-Like Growth Factor I; Osteophyte; Proto-Oncogene Proteins c-akt; Osteoarthritis; Chondrocytes; Cartilage, Articular; RNA; Sirtuins; Disease Models, Animal
PubMed: 37550003
DOI: 10.1136/ard-2023-224385 -
Advanced Materials (Deerfield Beach,... Nov 2023Restoring joint homeostasis is crucial for relieving osteoarthritis (OA). Current strategies are limited to unilateral efforts in joint lubrication, inhibition of...
Restoring joint homeostasis is crucial for relieving osteoarthritis (OA). Current strategies are limited to unilateral efforts in joint lubrication, inhibition of inflammation, free radicals scavenging, and cartilage regeneration. Herein, by modifying molybdenum disulfide (MoS ) with Mg -doped polydopamine and coating with polysulfobetaines, a dual-bionic photothermal nanozyme (MPMP) is constructed to mimic antioxidases/hyaluronan synthase for OA therapy. Photothermally enhanced lubrication lowers the coefficient of friction (0.028) in the early stage of OA treatment. The antioxidases-mimicking properties of MPMP nanozyme contribute to eliminating reactive oxygen and nitrogen species (ROS/RNS) (over 90% of scavenging ratio for H O /·OH/O /DPPH/ABTS ) and supplying O . With NIR irradiation, the MPMP nanozyme triggers thermogenesis (upregulating HSP70 expression) and Mg release, which promotes the chondrogenesis in inflammatory conditions by deactivating NF-κB/IL-17 signaling pathways and enhancing MAPK signaling pathway. Benefiting from HSP70 and Mg , MPMP-NIR shows HAS-mimicking activity to increase the intracellular (twofold) and extracellular (3.12-fold) HA production. Therefore, MPMP-NIR demonstrates superior spatiotemporally therapeutic effect on OA in mice model, in terms of osteophytes (83.41% of reduction), OARSI scores (88.57% of reduction), and ACAN expression (2.70-fold of increment). Hence, insights into dual-bionic nanozymes can be a promising strategy for OA therapy or other inflammation-related diseases.
Topics: Mice; Animals; Hyaluronan Synthases; Photothermal Therapy; Osteoarthritis; Inflammation; Signal Transduction; Reactive Oxygen Species
PubMed: 37459592
DOI: 10.1002/adma.202303299 -
Frontiers in Cell and Developmental... 2023Osteoarthritis (OA) is one of the leading causes of pain and disability in the elderly. Synovitis, cartilage destruction and osteophyte formation histologically manifest... (Review)
Review
Osteoarthritis (OA) is one of the leading causes of pain and disability in the elderly. Synovitis, cartilage destruction and osteophyte formation histologically manifest OA. Unfortunately, there is currently no effective therapy to delay its progression and the underlying mechanisms of OA require further exploration. Macrophage is a main cellular component of joint synovium. It is highly plastic and can be stimulated to polarize to different phenotypes, namely, the pro-inflammatory phenotype (M1) and the anti-inflammatory/tissue-repairing phenotype (M2). Ample evidence has demonstrated the vital roles of macrophages in the progression of OA. Imbalanced M1/M2 ratio is significantly related to OA severity indicating macrophage polarization might be a promising therapeutic target for OA. In this review, we summarized the involvements of polarized macrophages in synovitis, cartilage degradation, osteophyte formation and OA-related chronic pain. Promising therapies targeting macrophage polarization including the intra-articular cell/derivates-based therapy and the alternative non-invasive intervention such as photobiomodulation therapy were reviewed as well.
PubMed: 37954210
DOI: 10.3389/fcell.2023.1269724 -
Biomaterials Dec 2023Osteoarthritis (OA) is a common and complex inflammatory disorder that is frequently compounded by cartilage degradation, synovial inflammation, and osteophyte...
Osteoarthritis (OA) is a common and complex inflammatory disorder that is frequently compounded by cartilage degradation, synovial inflammation, and osteophyte formation. Damaged chondrocytes release multiple danger mediators that exacerbate synovial inflammation and accelerate the progression to OA. Conventional treatments targeting only a single mediator of OA have failed to achieve a strong therapeutic effect. Addressing the crucial role of multiple danger mediators in OA progression, we prepared polyethylenimine (PEI)-functionalized diselenide-bridged mesoporous silica nanoparticles (MSN-PEI) with cell-free DNA (cfDNA)-binding and anti-oxidative properties. In models of surgery-induced and collagenase-induced arthritis, we showed that these cationic nanoparticles attenuated cartilage degradation and provided strong chondroprotection against joint damage. Mechanistically, multiple target blockades alleviated oxidative stress and dampened cfDNA-induced inflammation by suppressing the M1 polarization of macrophages. This study suggests a beneficial direction for targeting multiple danger mediators in the treatment of intractable arthritis.
Topics: Humans; Silicon Dioxide; Osteoarthritis; Inflammation; Chondrocytes; Nanoparticles; Cell-Free Nucleic Acids
PubMed: 37948854
DOI: 10.1016/j.biomaterials.2023.122366 -
Cell Death and Differentiation Jan 2024Osteoarthritis (OA) is one of the most common joint diseases, there are no effective disease-modifying drugs, and the pathological mechanisms of OA need further...
Osteoarthritis (OA) is one of the most common joint diseases, there are no effective disease-modifying drugs, and the pathological mechanisms of OA need further investigation. Here, we show that H3K36 methylations were decreased in senescent chondrocytes and age-related osteoarthritic cartilage. Prrx1-Cre inducible H3.3K36M transgenic mice showed articular cartilage destruction and osteophyte formation. Conditional knockout Nsd1 mice, but not Nsd2 or Setd2 mice, replicated the phenotype of K36M/+; Prrx1-Cre mice. Immunostaining results showed decreased anabolic and increased catabolic activities in Nsd1 mice, along with decreased chondrogenic differentiation. Transcriptome and ChIP-seq data revealed that Osr2 was a key factor affected by Nsd1. Intra-articular delivery of Osr2 adenovirus effectively improved the homeostasis of articular cartilage in Nsd1 mice. In human osteoarthritic cartilages, both mRNA and protein levels of NSD1 and OSR2 were decreased. Our results indicate that NSD1-induced H3K36 methylations and OSR2 expression play important roles in articular cartilage homeostasis and OA. Targeting H3K36 methylation and OSR2 would be a novel strategy for OA treatment.
Topics: Mice; Humans; Animals; Chondrocytes; Methyltransferases; Osteoarthritis; Cartilage, Articular; Mice, Transgenic; Homeostasis; Histone-Lysine N-Methyltransferase
PubMed: 38012390
DOI: 10.1038/s41418-023-01244-8 -
Advanced Science (Weinheim,... Sep 2023The microenvironment and stem cell fate guidance of post-traumatic articular cartilage regeneration is primarily the focus of cartilage tissue engineering. In articular... (Review)
Review
The microenvironment and stem cell fate guidance of post-traumatic articular cartilage regeneration is primarily the focus of cartilage tissue engineering. In articular cartilage, stem cells are characterized by overlapping lineages and uneven effectiveness. Within the first 12 weeks after trauma, the articular inflammatory microenvironment (AIME) plays a decisive role in determining the fate of stem cells and cartilage. The development of fibrocartilage and osteophyte hyperplasia is an adverse outcome of chronic inflammation, which results from an imbalance in the AIME during the cartilage tissue repair process. In this review, the sources for the different types of stem cells and their fate are summarized. The main pathophysiological events that occur within the AIME as well as their protagonists are also discussed. Additionally, regulatory strategies that may guide the fate of stem cells within the AIME are proposed. Finally, strategies that provide insight into AIME pathophysiology are discussed and the design of new materials that match the post-traumatic progress of AIME pathophysiology in a spatial and temporal manner is guided. Thus, by regulating an appropriately modified inflammatory microenvironment, efficient stem cell-mediated tissue repair may be achieved.
Topics: Humans; Regeneration; Tissue Engineering; Stem Cells; Cartilage, Articular; Wound Healing; Arthritis
PubMed: 37518822
DOI: 10.1002/advs.202207715 -
Biomedicine & Pharmacotherapy =... Nov 2023Osteoarthritis (OA) is a chronic degenerative disease afflicting millions globally. Despite the development of numerous pharmacological treatments for OA, a substantial... (Review)
Review
Osteoarthritis (OA) is a chronic degenerative disease afflicting millions globally. Despite the development of numerous pharmacological treatments for OA, a substantial unmet need for effective therapies persists. The RANK/RANKL signaling pathway has emerged as a promising therapeutic target for OA, owing to its pivotal role in regulating osteoclast differentiation and activity. In this comprehensive review, we aim to elucidate the relevant mechanisms of OA mediated by RANK/RANKL signaling, including bone remodeling, inflammation, cartilage degradation, osteophyte formation, and pain sensitization. Furthermore, we discuss and summarize the cutting-edge strategies targeting RANK/RANKL signaling for OA therapy, encompassing approaches such as gene-based interventions and biomaterials-aided pharmacotherapy. In addition, we highlight the prevailing challenges associated with pharmacological OA treatments and explore potential future directions, approached through a clinical-translational lens.
Topics: Humans; Osteoprotegerin; Osteoarthritis; Inflammation; Bone Remodeling; Signal Transduction; RANK Ligand; Cartilage, Articular
PubMed: 37804812
DOI: 10.1016/j.biopha.2023.115646