RANKL targeted peptides inhibit osteoclastogenesis and attenuate adjuvant induced arthritis by inhibiting NF-κB activation and down regulating inflammatory cytokines

Computational design of anti-cancer peptides tailored to target specific tumor markers

Anti-cancer peptides (ACPs) are short peptides known for their ability to inhibit tumor cell proliferation, migration, and the formation of tumor blood vessels. In this study, we designed ACPs to target receptors often overexpressed in cancer using a systematic in silico approach. Three target receptors (CXCR1, DcR3, and OPG) were selected for their significant roles in cancer pathogenesis and tumor cell proliferation. Our peptide design strategy involved identifying interacting residues (IR) of these receptors, with their natural ligands serving as a reference for designing peptides specific to each receptor. The natural ligands of these receptors, including IL8 for CXCR1, TL1A for DcR3, and RANKL for OPG, were identified from the literature. Using the identified interacting residues (IR), we generated a peptide library through simple permutation and predicted the structure of each peptide. All peptides were analyzed using the web-based prediction server for Anticancer peptides, AntiCP. Docking simulations were then conducted to analyze the binding efficiencies of peptides with their respective target receptors, using VEGA ZZ and Chimera for interaction analysis. Our analysis identified HPKFIKELR as the interacting residues (IR) of CXCR-IL8. For DcR3, we utilized three domains from TL1A (TDSYPEP, TKEDKTF, LGLAFTK) as templates, along with two regions (SIKIPSS and PDQDATYP) from RANKL, to generate a library of peptide analogs. Subsequently, peptides for each receptor were shortlisted based on their predicted anticancer properties as determined by AntiCP and were subjected to docking analysis. After docking, peptides that exhibited the least binding energy were further analyzed for their detailed interaction with their respective receptors. Among these, peptides C9 (HPKFELY) and C7 (HPKFEWL) for CXCR1, peptides D6 (ADSYPQP) and D18 (AFSYPFP) for DcR3, and peptides P19 (PDTYPQDP) and p16 (PDQDATYP) for OPG, demonstrated the highest affinity and stronger interactions compared to the other peptides. Although in silico predictions indicated a favorable binding affinity of the designed peptides with target receptors, further experimental validation is essential to confirm their binding affinity, stability and pharmacokinetic characteristics.

Binding-induced fibrillogenesis peptide inhibits RANKL-mediated osteoclast activation against osteoporosis

Osteoporosis is primarily driven by an imbalance between bone resorption and formation, stemming from enhanced osteoclast activity during bone remodeling. At the crux of this mechanism lies the pivotal RANK-RANKL-OPG axis. In our study, we designed two binding-induced fibrillogenesis (BIF) peptides, namely BIFP and BIFY, targeting RANK and RANKL, respectively. These BIF peptides, with distinct hydrophilic and hydrophobic characteristics, assemble into nanoparticles (NPs) in aqueous solution. Through specific ligand-receptor interactions, these NPs efficiently target and bind to specific proteins, resulting in the formation of fibrous networks that effectively inhibit the RANK-RANKL associations. Experiments have confirmed the potent inhibitory effects of peptides on both osteoclast differentiation and function. Compared with the +RANKL controls, BIFP and BIFY demonstrated a more remarkable reduction in tartrate resistant acid phosphatase (TRAP)-positive cells, achieving an impressive decline of 82.8% and 70.7%, respectively. Remarkably, the administration of BIFP led to a substantial reduction in bone resorption pit area by 17.4%, compared to a significant increase of 92.4% in the +RANKL groups. In vivo experiments on an ovariectomized mouse model demonstrated that the BIFP treated group exhibited an impressive 2.6-fold elevation in bone mineral density and an astounding 4.0-fold enhancement in bone volume/total volume as against those of the PBS-treated group. Overall, BIF peptides demonstrate remarkable abilities to impede osteoclast differentiation, presenting promising prospects for the treatment of osteoporosis.

Evaluation of the anti-RANKL monoclonal antibody in rheumatoid arthritis rats

Objectives: In this study, we aimed to investigate the therapeutic effect of anti-receptor activator of nuclear factor kappa-κB ligand (RANKL) monoclonal antibodies R748-1-1-1, R748-1-1-2 and R748-1-1-3 on rheumatoid arthritis (RA) in a rat model.

Materials and methods: Gene cloning, hybridoma technology, affinity purification, enzyme-linked immunosorbent assay, general observation, hematoxylin-eosin staining, X-ray, and many other experimental techniques were used in this study.

Results: Improved collagen-induced arthritis (CIA) modeling was successfully constructed. The RANKL gene was cloned and the anti-RANKL monoclonal antibody was prepared. Following treatment with the anti-RANKL monoclonal antibody, the soft tissue swelling of the hind paws, the joint thickening, the narrowed joint gap, and the blurred edge of the bone joint were improved. The pathological changes such as synovial hyperplasia of fibrous tissue, cartilage and bone destruction were significantly decreased in the anti-RANKL monoclonal antibody-treated CIA group. Compared to the normal control group and phosphate buffer saline (PBS)-treated CIA group, the expression of tumor necrosis factor-alpha (TNF-α) and interleukin-1 (IL-1) in antibody-treated CIA group, positive drug-treated CIA group, and IgG-treated CIA group were decreased (p<0.05).

Conclusion: The anti-RANKL monoclonal antibody can promote the therapeutic effect of RA rats, indicating that the anti-RANKL monoclonal antibody has a certain potential value and may be beneficial to the further study of the mechanism of RA treatment.

Salvianolate Ameliorates Osteopenia and Improves Bone Quality in Prednisone-Treated Rheumatoid Arthritis Rats by Regulating RANKL/RANK/OPG Signaling

Rheumatoid arthritis (RA) is closely associated with periarticular osteopenia and leads to a high risk of generalized osteoporosis. Although glucocorticoid (GC) treatment ameliorates joint degradation and manages inflammation in RA, GC application may induce further bone quality deterioration in RA patients. Current treatments for RA lack relevant strategies for the prevention and treatment of osteopenia in RA. In this study, we aimed to investigate whether salvianolate treatment ameliorated osteopenia in prednisone-treated RA rats. Lewis rats with collagen-induced arthritis (CIA) were administered prednisone (PDN) or PDN plus salvianolate (PDN+Sal) treatment for 90 days. The effects of Sal were investigated in PDN-treated CIA rats. To further evaluate the effects of Sal under inflammatory conditions, we investigated the effects of Sal treatment on the TNF-α-induced inflammatory response in MC3T3-E1 osteoblasts. Bone histomorphometry, bone mineral density (BMD), bone biomechanical properties, micro-computed tomography (micro-CT), immunohistochemistry, RT-PCR and western blot analyses were performed to evaluate the effects of Sal. The results demonstrated that RA induced bone loss and bone quality deterioration, with high bone turnover in CIA rats. PDN+Sal treatment significantly increased BMD and trabecular/cortical bone mass, suppressed inflammation, and improved bone biomechanical properties compared to CIA control and PDN treatment. PDN+Sal treatment significantly suppressed bone resorption and the RANKL and RANKL/OPG ratios compared to PDN. PDN+Sal and PDN treatment significantly inhibited TNF-α by 82 and 83%, respectively, and both suppressed inflammation in CIA rats. However, there was no significant difference between PDN+Sal and PDN treatment alone in regard to bone formation parameters or the management of inflammation and arthropathy. Sal significantly increased Osterix, OPN, and Col1a1 while decreasing RANKL, TRAF6, and TRAIL gene in TNF-α-induced MC3T3-E1 osteoblasts. Sal significantly increased Osterix, OPN and RUNX2 while decreasing NF-κB, TRAF6 and IL-1β protein in TNF-α-induced MC3T3-E1 osteoblasts. The results suggested that salvianolate treatment ameliorated osteopenia and improved bone quality in prednisone-treated RA rats, and the potential mechanism may be related to the regulation of the RANKL/RANK/OPG signaling pathway, TRAIL-TRAF6-NFκB signal axis, and downregulation of inflammatory cytokines. Salvianolate could be used as a promising supplemental therapeutic strategy to ameliorate osteopenia and improve bone quality in GC-treated RA patients.

Melatonin inhibits RANKL‑induced osteoclastogenesis through the miR‑882/Rev‑erbα axis in Raw264.7 cells

Melatonin, secreted in a typical diurnal rhythm pattern, has been reported to prevent osteoporosis; however, its role in osteoclastogenesis remains unclear. In the present study, the ability of melatonin to inhibit receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis and the associated mechanism were investigated. Raw264.7 cells were cultured with RANKL (100 ng/ml) and macrophage colony-stimulating factor (M-CSF; 30 ng/ml) for 7 days, and tartrate-resistant acid phosphatase (TRAP) staining was used to detect osteoclastogenesis following treatment with melatonin. In addition, the effect of melatonin on cathepsin K and microRNA (miR)-882 expression was investigated via western blotting and reverse transcription-quantitative PCR. Melatonin significantly inhibited RANKL-induced osteoclastogenesis in Raw264.7 cells. From bioinformatics analysis, it was inferred that nuclear receptor subfamily 1 group D member 1 (NR1D1/Rev-erbα) may be a target of miR-882. In vitro, melatonin upregulated Rev-erbα expression and downregulated miR-882 expression in the osteoclastogenesis model. Rev-erbα overexpression boosted the anti-osteoclastogenesis effects of melatonin, whereas miR-882 partially diminished these effects. The present results indicated that the miR-882/Rev-erbα axis may serve a vital role in inhibiting osteoclastogenesis following RANKL and M-CSF treatment, indicating that Rev-erbα agonism or miR-882 inhibition may represent mechanisms through which melatonin prevents osteoporosis.

Periapical bone response to bacterial lipopolysaccharide is shifted upon cyclooxygenase blockage

OBJECTIVES

Infection, inflammation and bone resorption are closely related events in apical periodontitis development. Therefore, we sought to investigate the role of cyclooxygenase (COX) in osteoclastogenesis and bone metabolism signaling in periapical bone tissue after bacterial lipopolysaccharide (LPS) inoculation into root canals.

METHODOLOGY

Seventy two C57BL/6 mice had the root canals of the first molars inoculated with a solution containing LPS from E. coli (1.0 mg/mL) and received selective (celecoxib) or non-selective (indomethacin) COX-2 inhibitor. After 7, 14, 21 and 28 days the animals were euthanized and the tissues removed for total RNA extraction. Evaluation of gene expression was performed by qRT-PCR. Statistical analysis was performed using analysis of variance (ANOVA) followed by post-tests (α=0.05).

RESULTS

LPS induced expression of mRNA for COX-2 (Ptgs2) and PGE2 receptors (Ptger1, Ptger3 and Ptger4), indicating that cyclooxygenase is involved in periapical response to LPS. A signaling that favours bone resorption was observed because Tnfsf11 (RANKL), Vegfa, Ctsk, Mmp9, Cd36, Icam, Vcam1, Nfkb1 and Sox9 were upregulated in response to LPS. Indomethacin and celecoxib differentially modulated expression of osteoclastogenic and other bone metabolism genes: celecoxib downregulated Igf1r, Ctsk, Mmp9, Cd36, Icam1, Nfkb1, Smad3, Sox9, Csf3, Vcam1 and Itga3 whereas indomethacin inhibited Tgfbr1, Igf1r, Ctsk, Mmp9, Sox9, Cd36 and Icam1.

CONCLUSIONS

We demonstrated that gene expression for COX-2 and PGE2 receptors was upregulated after LPS inoculation into the root canals. Additionally, early administration of indomethacin and celecoxib (NSAIDs) inhibited osteoclastogenic signaling. The relevance of the cyclooxygenase pathway in apical periodontitis was shown by a wide modulation in the expression of genes involved in both bone catabolism and anabolism.

Creation of RANKL mutants with low affinity for decoy receptor OPG and their potential anti-fibrosis activity

Fibrosis is characterized by the progressive alteration of the tissue structure due to the excessive production of extracellular matrix (ECM). The signaling system encompassing Receptor Activator of Nuclear factor NF‐κB Ligand (RANKL)/RANK/Osteoprotegerin (OPG) was discovered to play an important role in the regulation of ECM formation and degradation in bone tissue. However, whether and how this signaling pathway plays a role in liver or pulmonary ECM degradation is unclear up to now. Interestingly, increased decoy receptor OPG levels are found in fibrotic tissues. We hypothesize that RANKL can stimulate RANK on macrophages and initiate the process of ECM degradation. This process may be inhibited by highly expressed OPG in fibrotic conditions. In this case, RANKL mutants that can bind to RANK without binding to OPG might become promising therapeutic candidates. In this study, we built a structure‐based library containing 44 RANKL mutants and found that the Q236 residue of RANKL is important for OPG binding. We show that RANKL_Q236D can activate RAW cells to initiate the process of ECM degradation and is able to escape from the obstruction by exogenous OPG. We propose that the generation of RANKL mutants with reduced affinity for OPG is a promising strategy for the exploration of new therapeutics against fibrosis.

Au Clusters Treat Rheumatoid Arthritis with Uniquely Reversing Cartilage/Bone Destruction

Super-small nanoclusters may intrinsically trigger specific molecular pathway for disease treatment in vitro/vivo. To prove the hypothesis the super-small nanoclusters, e.g., Au clusters, are directly used to treat rheumatoid arthritis (RA) in vitro/vivo. RA is a chronic autoimmune disease that is characterized by the inflammation of joints and the unreversible destruction of the cartilage/bone. Au clusters significantly suppress lipopolysaccharide (LPS)-induced proinflammatory mediator production in the murine macrophage cell line by inhibiting the signaling pathways that regulate the major proinflammatory mediator genes. In preclinical rat RA studies, Au clusters strongly prevent type II collagen-induced rat RA without systemic side effects. Compared with the clinical first-line anchored anti-RA drug, methotrexate, Au clusters equally inhibit inflammation in vivo. Type II collagen-induced rat RA is characterized with the destruction of cartilage/bone; treatment with Au clusters reverses the destruction of cartilage/bone to its normal state. This is because Au clusters directly inhibit receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation and function through the downregulation of osteoclast-specific genetic marker expression. However the methotrexate almost has no positive effect for this key issue in rat RA therapy. These data prove that the super-small nanoclusters, e.g., Au clusters, could be a novel candidate nanodrug for RA treatment.

Gold Clusters Prevent Inflammation-Induced Bone Erosion through Inhibiting the Activation of NF-κB Pathway

Inflammation-induced bone erosion is a major pathological factor in several chronic inflammatory diseases that often cause severe outcomes, such as rheumatoid arthritis and periodontitis. Plenty of evidences indicated that the inflammatory bone destruction was attributed to an increase in the number of bone-resorbing osteoclasts. However, anti-resorptive therapy alone failed to prevent bone loss in an inflammatory condition. Conventional anti-inflammation treatments are usually intended to suppress inflammation only, but ignore debilitating the subsequent bone destruction. Therefore, inhibition of proinflammatory activation of osteoclastogenesis could be an important strategy for the development of drugs aimed at preventing inflammatory bone destruction. Methods: In this study, we synthesized a peptide coated gold cluster to evaluate its effects on inflammatory osteoclastogenesis in vitro and inflammation-induced bone destruction in vivo. The in vitro anti-inflammation and anti-osteoclastogenesis effects of the cluster were evaluated in LPS-stimulated and receptor activator of nuclear factor κB ligand (RANKL) stimulated macrophages, respectively. The LPS-induced expression of crucial pro-inflammation cytokines and RANKL-induced osteoclastogenesis as well as the activation of NF-κB pathway in both situations were detected. The inflammation-induced RANKL expression and subsequent inflammatory bone destruction in vivo were determined in collagen-immunized mice. Results: The gold cluster strongly suppresses RANKL-induced osteoclast formation via inhibiting the activation of NF-κB pathway in vitro. Moreover, treatment with the clusters at a dose of 5 mg Au/kg.bw significantly reduces the severity of inflammation-induced bone and cartilage destruction in vivo without any significant toxicity effects. Conclusion: Therefore, the gold clusters may offer a novel potent therapeutic stratagem for inhibiting chronic inflammation associated bone destruction.

The RANK/RANKL/OPG system in tumorigenesis and metastasis of cancer stem cell: potential targets for anticancer therapy

The molecular triad involving receptor activator of nuclear factor kβ (RANK)/RANK ligand (RANKL)/osteoprotegerin cytokine system has been well implicated in several physiological and pathological processes including bone metabolism, mammary gland development, regulation of the immune function, tumorigenesis and metastasis of cancer stem cell, thermoregulation, and vascular calcification. However, this review aimed to summarize several original and up-to-date articles focusing on the role of this signaling system in cancer cell development and metastasis as well as potential therapeutic agents targeting any of the three tumor necrotic factor super family proteins and/or their downstream signaling pathways. The RANK/RANKL axis has direct effects on tumor cell development. The system is well involved in the development of several primary and secondary tumors including breast cancer, prostate cancer, bone tumors, and leukemia. The signaling of this triad system has also been linked to tumor invasiveness in the advanced stage. Bone is by far the most common site of cancer metastasis. Several therapeutic agents targeting this system have been developed. Among them, a monoclonal antibody, denosumab, was clinically approved for the treatment of osteoporosis and cancer-related diseases.

Astragaloside I Stimulates Osteoblast Differentiation Through the Wnt/β-catenin Signaling Pathway

Astragaloside I (As-I), one of the main active ingredients in Astragalus membranaceus, is believed to have osteogenic properties, but this hypothesis has not been investigated in detail. In the present work, the As-I-induced osteogenic effects and its underlying mechanism were studied in MC3T3-E1 cells. The results indicated that the cellular levels of ALP and extracellular matrix calcium increased in a dose-dependent manner by As-I. To clarify the mechanisms involved in this process, the effect of As-I on the key osteogenic-related genes was investigated. We found that As-I stimulated the expression of β-catenin and Runx2 in MC3T3-E1 cells, which play central roles in the Wnt/β-catenin signaling pathway, suggesting that As-I could promote osteoblastic differentiation by regulating the Wnt/β-catenin signaling pathway. Moreover, the osteogenic effect of As-I could be inhibited by DKK-1, which is the classical inhibitor of Wnt/β-catenin-signaling pathway. Furthermore, As-I also increased BMP-2, BGP and OPG/RANKL expression, which are also activated by Wnt/β-catenin signaling pathway. Taken together, our findings show that As-I stimulates osteoblast differentiation through the Wnt/β-catenin signaling pathway, which also activates the BMP pathway and RANK pathway, thus highlighting the As-I for pharmaceutical and medicinal applications such as treating bone disease. Copyright © 2016 John Wiley & Sons, Ltd.

Explaining RANKL inhibition by OPG through quantum biochemistry computations and insights into peptide-design for the treatment of osteoporosis

Quantum biochemistry computations are applied to precisely describe important protein–protein interactions, providing a basis for the design of inhibitory peptides against osteoporosis.

The effect of curcumin and its nanoformulation on adjuvant-induced arthritis in rats

Background

Rheumatoid arthritis (RA), induced by the prolonged inappropriate inflammatory responses, is one of the most prevalent of all chronic inflammatory joint diseases. Curcumin (CM), a yellow hydrophobic polyphenol derived from the herb turmeric, has various pharmacological activities against many chronic diseases and acts by inhibiting cell proliferation and metastasis and downregulating various factors, including nuclear factor kappa B, interleukin-1β and TNF-α. Given the pathogenesis of RA, we hypothesized that the drug also has antiarthritic effects. The aims of the present study included the following: 1) examining the therapeutic effect of CM administered via intravenous (iv) injection on RA and 2) formulating the drug into oil–water nanoemulsions (Ns) to overcome the low oral bioavailability of CM and achieve oral delivery of the drug.

Methods

The effect of CM administered through iv injection on adjuvant-induced arthritis in rats was studied in terms of paw swelling, weight indices of the thymus and spleen, and pathological changes in nuclear factor kappa B expression and inflammatory cytokines. Methotrexate was used as a positive control. The CM-Ns were prepared using a high-pressure homogenizing method and characterized with respect to the particle size and morphology. The stability of the CM-Ns in simulated gastrointestinal (GI) fluids and in vitro release were also investigated. A pharmacokinetic study of the CM-Ns and suspensions in which the plasma levels were determined using an high performance liquid chromatography method and the pharmacokinetic parameters were calculated based on a statistical moment theory was also performed in rats.

Results

CM administered via iv injection had a therapeutic effect on RA similar to methotrexate. CM-Ns with a diameter of approximately 150 nm were successfully prepared, and the drug was well encapsulated into the Ns without degradation in simulated GI conditions. The area under the curve (AUC) and C_max for the CM-Ns were more than threefold greater than those for the suspensions; moreover, similar decreases in the levels of TNF-α and interleukin-1β in both synovial fluid and blood serum were obtained from oral administration of CM-Ns and iv injection.

Conclusion

CM was an effective antiarthritic agent, and the present N formulation appeared to be a promising system that allowed RA therapy with CM to be converted from iv to oral administration.

CCN2 enhances RANKL-induced osteoclast differentiation via direct binding to RANK and OPG

CCN family protein 2/connective tissue growth factor (CCN2/CTGF) is a multi-potent factor for mesenchymal cells such as chondrocytes, osteoblasts, osteoclasts, and endothelial cells. CCN2 is also known as a modulator of other cytokines and receptors via direct molecular interactions with them. We screened additional factors binding to CCN2 and found receptor activator of NF-kappa B (RANK) as one of them. RANK is also known as TNF-related activation-induced cytokine (TRANCE) receptor, and its signaling plays a critical role in osteoclastogenesis. Notable affinity between CCN2 and RANK was confirmed by using surface plasmon resonance (SPR) analysis. In fact, CCN2 enhanced the RANK-mediated signaling, such as occurs in NF-kappa B, p38 and JNK pathways, in pre-osteoclastic RAW264.7 cells; whereas CCN2 had no influence on RANK-RANK ligand (RANKL) binding. Moreover, CCN2 also significantly bound to osteoprotegerin (OPG), which is a decoy receptor of RANKL. Of note, OPG markedly inhibited the binding between CCN2 and RANK; and CCN2 canceled the inhibitory effect of OPG on osteoclast differentiation. These findings suggest CCN2 as a candidate of the fourth factor in the RANK/RANKL/OPG system for osteoclastogenesis, which regulates OPG and RANK via direct interaction.

Inhibition of adjuvant-induced arthritis by nasal administration of novel synthetic peptides from heat shock protein 65

Background

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease mediated by T cells. The aim of the present study was to investigate the therapeutic efficacy of synthetic peptides (HP-R1, HP-R2 and HP-R3), derived from the sequence of 65-kD mycobacterial heat shock protein (HSP), in the treatment of RA using adjuvant-induced arthritis (AA) animal model.

Methods

AA was induced by a single intradermal injection Freund’s complete adjuvant in male Lewis rats. At the first clinical sign of disease, rats were administered nasally by micropipette of peptides or phosphate buffer saline (PBS). Disease progression was monitored by measurement of body weight, arthritis score and paw swelling. The changes of histopathology were assessed by hematoxylin eosin staining. The serum levels of tumor necrosis factor (TNF) - alpha and interleukin (IL)-4 were measured by enzyme-linked immunosorbent assay (ELISA).

Results

The peptides efficiently inhibited the footpad swelling and arthritic symptoms in AA rats. The synthetic peptides displayed significantly less inflammatory cellular infiltration and synovium hyperplasia than model controls. This effect was associated with a suppression of pro-inflammatory cytokine TNF-alpha production and an increase of anti-inflammatory cytokine IL-4 production after peptides treatment.

Conclusions

These results suggest that the synthetic peptides derived from HSP65 induce highly effective protection against AA, which is mediated in part by down-regulation of inflammatory cytokines, and support the view that the synthetic peptides is a potential therapy for RA that may help to diminish both joint inflammation and destruction.

Therapeutic effects of total steroid saponin extracts from the rhizome of Dioscorea zingiberensis C.H.Wright in Freund's complete adjuvant induced arthritis in rats

The aim of our present study is to explore the anti-arthritic potential effect of total steroid saponins (TSSNs) extracted from the rhizome of Dioscorea zingiberensis C.H.Wright (DZW) and to investigate the underlying mechanisms. This work was performed using adjuvant-induced arthritis (AIA) rats in vivo and lipopolysaccharide (LPS) simulated 264.7 macrophage cells in vitro. In AIA-induced arthritic rats, TSSN significantly alleviated the arthritic progression through evaluating arthritic score, immune organ indexes, paw swelling, and body weight. This phenomenon was well correlated with significant suppression of the overproduction of inflammation cytokines (IL-1, IL-1β, IL-6, and TNF-α), oxidant stress makers (MDA and NO), eicosanoids (LTB4 and PGE2), and inflammatory enzymes (5-LOX and COX-2) versus the AIA rats without treatment. On the contrary, the release of SOD and IL-10 was profoundly increased. What's more, TSSN could obviously ameliorate the translocation of NF-κB to the nucleus through phosphorylation of the p65 and IκBα in vivo and in vitro. The current findings demonstrated that TSSN could protect the injured ankle joint from further deterioration and exert its satisfactory anti-arthritis properties through anti-inflammatory and anti-oxidant effects via inactivating the NF-κB signal pathway. This research implies that DZW may be a useful therapeutic agent for the treatment of human arthritis.

Emerging immunotherapies for rheumatoid arthritis

Novel treatments in development for rheumatoid arthritis target 3 broad areas: cytokines, cells, and signaling pathways. Therapies from each domain share common advantages (for example previously demonstrated efficacy, potential long-term immunomodulation, and oral administration respectively) that have stimulated research in each area but also common obstacles to their development. In this review recent progress in each area will be discussed alongside the factors that have impeded their path to clinical use.