Proinflammatory Effects of IL-1β Combined with IL-17A Promoted Cartilage Degradation and Suppressed Genes Associated with Cartilage Matrix Synthesis In Vitro

Anti-arthritis Effects of Zingiberaceae Extracts on Models of Inflammatory Joint Disease

Due to this becoming an aging society, the number of arthritis cases has been increasing. Unfortunately, some currently available medications can cause adverse effects. Using herbal remedies as a form of alternative medicine is becoming increasingly popular. Zingiber officinale (ZO), Curcuma longa (CL), and Kaempferia parviflora (KP) are herbal plants in the Zingiberaceae family that have potent anti-inflammatory effects. This study investigates the anti-inflammatory and chondroprotective effects of ZO, CL, and KP extracts on in vitro and ex vivo inflammatory models. The combinatorial anti-arthritis effect of each extract is also evaluated in an in vivo model. ZO extract preserves cartilaginous proteoglycans in proinflammatory cytokines-induced porcine cartilage explant in a fashion similar to that of CL and KP extracts and suppresses the expression of major inflammatory mediators in SW982 cells, particularly the COX2 gene. CL extract downregulates some inflammatory mediators and genes-associated cartilage degradation. Only KP extract shows a significant reduction in S-GAGs release in a cartilage explant model compared to the positive control, diacerein. In SW982 cells, it strongly suppresses many inflammatory mediators. The active constituents of each extract selectively downregulate inflammatory genes. The combined extracts show a reduction in inflammatory mediators to a similar degree as the combined active constituents. Reductions in paw swelling, synovial vascularity, inflammatory cell infiltration, and synovial hyperplasia are found in the combined extracts-treated arthritic rats. This study demonstrates that a combination of ZO, CL, and KP extracts has an anti-arthritis effect and could potentially be developed into an anti-arthritis cocktail for arthritis treatment.

Pathogenic Role of Adipose Tissue-Derived Mesenchymal Stem Cells in Obesity and Obesity-Related Inflammatory Diseases

Adipose tissue-derived mesenchymal stem cells (ASCs) are adult stem cells, endowed with self-renewal, multipotent capacities, and immunomodulatory properties, as mesenchymal stem cells (MSCs) from other origins. However, in a pathological context, ASCs like MSCs can exhibit pro-inflammatory properties and attract inflammatory immune cells at their neighborhood. Subsequently, this creates an inflammatory microenvironment leading to ASCs' or MSCs' dysfunctions. One such example is given by obesity where adipogenesis is impaired and insulin resistance is initiated. These opposite properties have led to the classification of MSCs into two categories defined as pro-inflammatory ASC1 or anti-inflammatory ASC2, in which plasticity depends on the micro-environmental stimuli. The aim of this review is to (i) highlight the pathogenic role of ASCs during obesity and obesity-related inflammatory diseases, such as rheumatoid arthritis, multiple sclerosis, psoriasis, inflammatory bowel disease, and cancer; and (ii) describe some of the mechanisms leading to ASCs dysfunctions. Thus, the role of soluble factors, adhesion molecules; TLRs, Th17, and Th22 cells; γδ T cells; and immune checkpoint overexpression will be addressed.

Cell morphology as a biological fingerprint of chondrocyte phenotype in control and inflammatory conditions

Introduction

Little is known how inflammatory processes quantitatively affect chondrocyte morphology and how single cell morphometric data could be used as a biological fingerprint of phenotype.

Methods

We investigated whether trainable high-throughput quantitative single cell morphology profiling combined with population-based gene expression analysis can be used to identify biological fingerprints that are discriminatory of control vs. inflammatory phenotypes. The shape of a large number of chondrocytes isolated from bovine healthy and human osteoarthritic (OA) cartilages was quantified under control and inflammatory (IL-1β) conditions using a trainable image analysis technique measuring a panel of cell shape descriptors (area, length, width, circularity, aspect ratio, roundness, solidity). The expression profiles of phenotypically relevant markers were quantified by ddPCR. Statistical analysis, multivariate data exploration, and projection-based modelling were used for identifying specific morphological fingerprints indicative of phenotype.

Results

Cell morphology was sensitive to both cell density and IL-1β. In both cell types, all shape descriptors correlated with expression of extracellular matrix (ECM)- and inflammatory-regulating genes. A hierarchical clustered image map revealed that individual samples sometimes responded differently in control or IL-1β conditions than the overall population. Despite these variances, discriminative projection-based modeling revealed distinct morphological fingerprints that discriminated between control and inflammatory chondrocyte phenotypes: the most essential morphological characteristics attributable to non-treated control cells was a higher cell aspect ratio in healthy bovine chondrocytes and roundness in OA human chondrocytes. In contrast, a higher circularity and width in healthy bovine chondrocytes and length and area in OA human chondrocytes indicated an inflammatory (IL-1β) phenotype. When comparing the two species/health conditions, bovine healthy and human OA chondrocytes exhibited comparable IL-1β-induced morphologies in roundness, a widely recognized marker of chondrocyte phenotype, and aspect ratio.

Discussion

Overall, cell morphology can be used as a biological fingerprint for describing chondrocyte phenotype. Quantitative single cell morphometry in conjunction with advanced methods for multivariate data analysis allows identifying morphological fingerprints that can discriminate between control and inflammatory chondrocyte phenotypes. This approach could be used to assess how culture conditions, inflammatory mediators, and therapeutic modulators regulate cell phenotype and function.

Increased Chondroprotective Effect of Combining Hyaluronic Acid with a Glucocorticoid Compared to Separate Administration on Cytokine-Treated Osteoarthritic Chondrocytes in a 2D Culture

Intra-articular injections of glucocorticoids (GC) or hyaluronic acid (HA) are commonly used interventions for patients suffering from knee osteoarthritis (OA). Both substances are combined to achieve a chondroprotective and anti-inflammatory effect. Clinical studies have shown benefits, but data on the cellular level are still lacking. This study aimed to investigate the effect of the GC triamcinolone hexacetonide, HA, and a mix of both substances on cytokine-treated chondrocytes in vitro. Chondrocytes isolated from human articular cartilage were seeded on 6- and 24-well plates. Mimicking OA’s inflammatory state, cells were treated with IL-1β and IL-17 for six days, whereby, after three days, test substances (10%) were added to the culture medium. Chondrocytes were analyzed on days three and six concerning their actin polymerization, expression of anabolic and catabolic genes, metabolic activity, cytokine release, and reactive oxygen species (ROS). Adding HA or GC/HA to the inflammatory culture medium increased the metabolic activity of chondrocytes, while groups containing GC reduced catabolic gene expression and the release of TNF-α. In addition, enhanced F-actin content was shown supplementing HA or GC/HA to the culture medium. Supplementing GC with HA leads to an anti-inflammatory and chondroprotective effect by diminishing the side effects of GC supplementation alone.

Theaflavin-3,3 ′ -Digallate Protects Cartilage from Degradation by Modulating Inflammation and Antioxidant Pathways

Background

Osteoarthritis (OA) is a common degenerative joint disease that may be closely linked to inflammation and oxidative stress destroying the balance of cartilage matrix. Theaflavin-3,3′-digallate (TFDG), a natural substance derived from black tea, has been reported to restrict the activity of inflammatory cytokines and effectively eliminate reactive oxygen species (ROS) in various diseases. However, it is not clear whether TFDG can improve OA.

Methods

Chondrocytes were treated with or without IL-1β and 20 μM and 40 μM TFDG. The effect of TFDG on the proliferation of chondrocytes was detected by CCK8. RT-qPCR was used to detect the gene expression of inflammatory factors, extracellular matrix synthesis, and degradation genes. Western blot and immunofluorescence assays were used to detect the protein expression. The fluorescence intensity of reactive oxygen species labeled by DCFH-DA was detected by flow cytometry. We established an OA rat model by performing destabilized medial meniscus (DMM) surgery to observe whether TFDG can protect chondrocytes under arthritis in vivo.

Results

TFDG was found to inhibit proinflammatory factors (IL-6, TNF-α, iNOS, and PGE) and matrix-degrading enzymes (MMP13, MMP3, and ADAMTS5) expression and protected extracellular matrix components of chondrocytes (ACAN, COL2, and SOX9). TFDG accelerated the scavenging of ROS caused by IL-1β according to the Nrf2 signaling pathway activation. At the same time, TFDG suppressed the PI3K/AKT/NF-κB and MAPK signaling pathways to delay the inflammatory process. The cartilage of DMM rats receiving TFDG showed lower Osteoarthritis Research Society International (OARSI) scores and expressed higher levels of COL2 and Nrf2 compared with those of rats in the DMM group.

Conclusion

TFDG could protect cartilage from degradation and alleviate osteoarthritis in rats, which suggests that TFDG has potential as a drug candidate for OA therapy.

Hyperosmolar Ionic Solutions Modulate Inflammatory Phenotype and sGAG Loss in a Cartilage Explant Model

OBJECTIVE

The objective of this study was to compare the effects of hyperosmolar sodium (Na+), lithium (Li+) and potassium (K+) on catabolic and inflammatory osteoarthritis (OA) markers and sulfated glycosaminoglycan (sGAG) loss in TNF-α-stimulated cartilage explants.

METHODS

Explants from bovine stifle joints were stimulated with TNF-α for 1 day to induce cartilage degradation followed by supplementation with 50 mM potassium chloride (KCl), 50 mM lithium chloride (LiCl), 50 mM sodium chloride (NaCl), or 100 nM dexamethasone for an additional 6 days. We assessed the effect of TNF-α stimulation and hyperosmolar ionic treatment on sGAG loss and expression of OA-associated proteins: ADAMTS-5, COX-2, MMP-1, MMP-13, and VEGF.

RESULTS

TNF-α treatment increased sGAG loss (P < 0.001) and expression of COX-2 (P = 0.018), MMP-13 (P < 0.001), and VEGF (P = 0.017) relative to unstimulated controls. Relative to activated controls, LiCl and dexamethasone treatment attenuated sGAG loss (P = 0.008 and P = 0.042, respectively) and expression of MMP-13 (P = 0.005 and P = 0.036, respectively). In contrast, KCl treatment exacerbated sGAG loss (P = 0.032) and MMP-1 protein expression (P = 0.010). NaCl treatment, however, did not alter sGAG loss or expression of OA-related proteins. Comparing LiCl and KCl treatment shows a potent reduction (P < 0.05) in catabolic and inflammatory mediators following LiCl treatment.

CONCLUSION

These results suggest that these ionic species elicit varying responses in TNF-α-stimulated explants. Cumulatively, these findings support additional studies of hyperosmolar ionic solutions for potential development of novel intraarticular injections targeting OA.

Adenosine deaminase modulates metabolic remodeling and orchestrates joint destruction in rheumatoid arthritis

Rheumatoid Arthritis (RA) is a chronic autoimmune disease associated with inflammation and joint remodeling. Adenosine deaminase (ADA), a risk factor in RA, degrades adenosine, an anti-inflammatory molecule, resulting in an inflammatory bias. We present an integrative analysis of clinical data, cytokines, serum metabolomics in RA patients and mechanistic studies on ADA-mediated effects on in vitro cell culture models. ADA activity differentiated patients into low and high ADA sets. The levels of the cytokines TNFα, IFNγ, IL-10, TGFβ and sRANKL were elevated in RA and more pronounced in high ADA sets. Serum metabolomic analysis shows altered metabolic pathways in RA which were distinct between low and high ADA sets. Comparative analysis with previous studies shows similar pathways are modulated by DMARDs and biologics. Random forest analysis distinguished RA from control by methyl-histidine and hydroxyisocaproic acid, while hexose-phosphate and fructose-6-phosphate distinguished high ADA from low ADA. The deregulated metabolic pathways of High ADA datasets significantly overlapped with high ADA expressing PBMCs GEO transcriptomics dataset. ADA induced the death of chondrocytes, synoviocyte proliferation, both inflammation in macrophages and their differentiation into osteoclasts and impaired differentiation of mesenchymal stem cells to osteoblasts and mineralization. PBMCs expressing elevated ADA had increased expression of cytokines and P2 receptors compared to synovial macrophages which has low expression of ADA. Our data demonstrates increased cytokine levels and distinct metabolic signatures of RA based on the ADA activity, suggests an important role for ADA in the pathophysiology of RA joints and as a potential marker and therapeutic target in RA patients.

Platelet-Rich Plasma Suppresses Inflammation Reaction of Rat Articular Chondrocytes via Wingless-Related Integration Site/β-Catenin Axis

Our study aims to elucidate the role of platelet-rich plasma (PRP) in rats chondrocytes inflammation and mechanism. PRP was obtained from 8 weeks old rats. Then, the knee joint of bilateral hind limbs was dissected and articular chondrocytes were obtained in super-clean table after dislocation and identified at the second generation during culture and passage. Chondrocytes were divided into control group 1 (addition of saline), control group 2 (IWP-2, Wnt/β-catenin axis inhibitor) and experimental group (PRP) followed by analysis of mRNA levels of glycogen synthase kinase-3 (GSK-3β), low-density lipoprotein receptor-associated protein 5 (LRP5), Wnt1 and β-catenin by RT-PCR, IL-1 and TNF-α after 1 week by ELISA. The second generation articular chondrocytes presented polygonal or triangular cell morphology, positive for collagen II and toluidine blue staining. PRP addition significantly reduced GSK-3β and LRP5 mRNA level, and increased β-catenin and Wnt1 mRNA levels in chondrocytes. Meanwhile, it suppressed IL-1 and TNF-α secretion and Wnt protein production inhibitor 2. PRP might suppresses inflammatory factors production of rat articular chondrocytes through inhibiting Wnt/β-catenin axis.

Chondroprotective effect of Alpinia oxyphylla extract in experimentally induced cartilage degradation in rabbit articular cartilage explants

Alpinia oxyphylla is a widely used medicinal herb for diarrhea, gastralgia, tumors, hypertention, and cerebrovascular disorders. Here, we evaluated the chondroprotective effect of A. oxyphylla dried fruit ethanol extract (AOE) against cartilage degradation in rabbit articular cartilage explants. Treatment of interleukin-1α (IL-1α) and plasminogen increased degraded collagen release in culture supernatants, but pretreatment of AOE (50, 100, 200 µg/ml) inhibited the collagen release in dose-dependent manner. To examine the mechanism of action of AOE on chondroprotection, the level of matrix metalloproteinases-3 (MMP-3), matrix metalloproteinases-13 (MMP-13), tissue inhibitor of metalloprotease-1 (TIMP-1), and inflammatory mediators like prostaglandin E₂ (PGE₂ ) and nitric oxide (NO) was evaluated. AOE inhibited upregulation of MMP-3 and MMP-13 and downregulation of TIMP-1 and also reduced increase of PGE₂ and NO level induced by exposure of IL-1α and plasminogen. These results indicate that AOE show chondroprotective effect through inhibiting collagen degradation via regulating MMPs, TIMP-1, and inflammatory mediators. PRACTICAL APPLICATIONS: Osteoarthritis (OA) is a one of the most common chronic disorders in elderly persons. Because the regenerative power of joint articular cartilage is very low, treatment of OA is difficult to expect complete recovery. Therefore, there is a need to develop a therapeutic agent that can safely and effectively inhibit the cartilage destruction. For the first time, we exhibited the inhibitory effect of AOE on collagen degradation through regulating MMPs and TIMP-1 in articular cartilage explants. These findings support AOE could be used as herbal therapeutic application for protecting articular cartilage to prevent OA.

An Evidence-Based Systematic Review of Human Knee Post-Traumatic Osteoarthritis (PTOA): Timeline of Clinical Presentation and Disease Markers, Comparison of Knee Joint PTOA Models and Early Disease Implications

Understanding the causality of the post-traumatic osteoarthritis (PTOA) disease process of the knee joint is important for diagnosing early disease and developing new and effective preventions or treatments. The aim of this review was to provide detailed clinical data on inflammatory and other biomarkers obtained from patients after acute knee trauma in order to (i) present a timeline of events that occur in the acute, subacute, and chronic post-traumatic phases and in PTOA, and (ii) to identify key factors present in the synovial fluid, serum/plasma and urine, leading to PTOA of the knee in 23-50% of individuals who had acute knee trauma. In this context, we additionally discuss methods of simulating knee trauma and inflammation in in vivo, ex vivo articular cartilage explant and in vitro chondrocyte models, and answer whether these models are representative of the clinical inflammatory stages following knee trauma. Moreover, we compare the pro-inflammatory cytokine concentrations used in such models and demonstrate that, compared to concentrations in the synovial fluid after knee trauma, they are exceedingly high. We then used the Bradford Hill Framework to present evidence that TNF-α and IL-6 cytokines are causal factors, while IL-1β and IL-17 are credible factors in inducing knee PTOA disease progresssion. Lastly, we discuss beneficial infrastructure for future studies to dissect the role of local vs. systemic inflammation in PTOA progression with an emphasis on early disease.

Post-treatment of hyaluronan to decrease the apoptotic effects of carprofen in canine articular chondrocyte culture

A major concern associated with the use of drugs is their adverse side effects. Specific examples of the drugs of concern include antibiotic agents and non-steroidal anti-inflammatory drugs. Despite the presence of a high degree of efficacy for specific conditions, these drugs may deteriorate the surrounding tissues that are exposed to them. Often, carprofen is used for joint inflammation; however, it may stimulate cartilage degradation which can then lead to osteoarthritis progression. In this study, hyaluronan was combined with carprofen treatment in three different applications (pre-treatment, co-treatment and post-treatment) on normal canine chondrocytes to determine whether Hyaluronan (HA) is capable of mitigating the degree of chondrotoxicity of carprofen. Our findings revealed that carprofen at IC₂₀ (0.16 mg/mL) decreased viability and increased nitric oxide (NO) production. Importantly, carprofen induced the apoptosis of canine chondrocytes via the up-regulation of Bax, Casp3, Casp8, Casp9 and NOS2 as compared to the control group. Although the co-treatment of HA and carprofen appeared not to further alleviate the chondrotoxicity of carprofen due to the presence of a high number of apoptotic chondrocytes, post-treatment with HA (carprofen treatment for 24 h and then changed to HA for 24 h) resulted in a decrease in chondrocyte apoptosis by the down-regulation of Bax, Casp3, Casp8, Casp9, NOS2, along with NO production when compared with the treatment of carprofen for 48 h (P < 0.05). These results suggest that HA can be used as a therapeutic agent to mitigate the degree of chondrotoxicity of carprofen.