Pathological Changes In Joints Research Articles

Nanoparticle-Mediated Multiple Modulation of Bone Microenvironment To Tackle Osteoarthritis.

Development of nanomedicines that can collaboratively scavenge reactive oxygen species (ROS) and inhibit inflammatory cytokines, along with osteogenesis promotion, is essential for efficient osteoarthritis (OA) treatment. Herein, we report the design of a ROS-responsive nanomedicine formulation based on fibronectin (FN)-coated polymer nanoparticles (NPs) loaded with azabisdimethylphoaphonate-terminated phosphorus dendrimers (G4-TBP). The constructed G4-TBP NPs-FN with a size of 268 nm are stable under physiological conditions, can be specifically taken up by macrophages through the FN-mediated targeting, and can be dissociated in the oxidative inflammatory microenvironment. The G4-TBP NPs-FN loaded with G4-TBP dendrimer having intrinsic anti-inflammatory property and FN having both anti-inflammatory and antioxidative properties display integrated functions of ROS scavenging, hypoxia attenuation, and macrophage M2 polarization, thus protecting macrophages from apoptosis and creating designed bone immune microenvironment for stem cell osteogenic differentiation. These characteristics of the G4-TBP NPs-FN lead to their effective treatment of an OA model in vivo to reduce pathological changes of joints including synovitis inhibition and cartilage matrix degradation and simultaneously promote osteogenic differentiation for bone repair. The developed nanomedicine formulation combining the advantages of both bioactive phosphorus dendrimers and FN to treat OA may be developed for immunomodulatory therapy of different inflammatory diseases.

Danggui Niantong decoction ameliorates joint inflammation and cardiopulmonary injury in TNF-Tg mice

Objective: Rheumatoid arthritis (RA) is a common autoimmune disease characterized by multiple joint lesions and systemic complications. Danggui Niantong decoction (DGNTT) has been clinically used for RA treatment; however, its beneficial effect on cardiopulmonary complications has not been reported. Methods: Female tumor necrosis factor-transgenic (TNF-Tg) mice were used to evaluate the therapeutic effects of DGNTT on arthritis and cardiopulmonary complications. Methotrexate (MTX) served as a positive control. Histopathological assessment of the joint sections was performed using hematoxylin and eosin (HE), Alcian Blue/Orange G, and tartrate-resistant acid phosphatase staining. Bone mass was assessed by micro-computed tomography, inflammatory infiltrates in the heart and lungs were evaluated by HE staining, cardiopulmonary fibrotic injury was identified by Masson’s trichrome staining, and hypertrophy of mouse cardiomyocytes was measured by wheat germ agglutinin (WGA) staining. Results: DGNTT mitigated the inflammation of the ankle joint synovium, decreased the number of osteoclasts, and increased the area of cartilage and bone mass in TNF-Tg mice. In addition, DGNTT decreased the infiltration of inflammatory cells into the lung and heart tissues, accompanied by a reduction in cardiopulmonary fibrosis and myocardial cell hypertrophy in TNF-Tg mice. As a positive control drug, MTX attenuated the pathological changes in joints, but had no beneficial effect on cardiopulmonary inflammation and fibrosis in TNF-Tg mice. Conclusions: DGNTT improved joint lesions and alleviated cardiopulmonary complications in TNF-Tg mice.

Comparison of joint status using ultrasound assessments and Haemophilia Joint Health Score 2.1 in children with haemophilia.

Ultrasound (US) has gained popularity in the evaluation of haemophilic joint diseases because it enables the imaging of soft-tissue lesions in the joints and bone-cartilage lesions. We aimed to determine the correlation between US evaluations and clinical assessments performed using HJHS 2.1 and to evaluate their respective characteristics in assessing early haemophilic arthropathy. A total of 178 joints (32 knees, 85 elbows, and 61 ankles) in 45 haemophilia A patients (median age, 10 years; range, 6-15) were assessed using US and HJHS 2.1. Ultrasonographic scoring was performed in consensus assessments by one imager by using the US scores. The total HJHS 2.1 and US scores showed a strong correlation (rS=0.651, P=0.000, CI: 0.553-0.763), with an excellent correlation for the elbows (rS=0.867, P=0.000, CI: 0.709-0.941) and a substantial correlation for the knees (rS=0.681, P=0.000, CI: 0.527-0.797). The correlation for the ankles was relatively moderate (rS=0.518, P=0.000, CI: 0.308-0.705). Nine subjects (15.5%) without abnormalities, as indicated by HJHS 2.1, showed haemophilic arthropathy in US scoring. All nine joints showed moderate (1/9) to severe (8/9) synovial thickening in the ankle (5/9) and elbow joints (4/9). In contrast, 50 joints (50.5%) showed normal US scores and abnormal changes as indicated by HJHS 2.1. S scores correlated well with HJHS 2.1 for overall and individual joints. US could identify some early pathological changes in joints showing normal clinical findings, but still cannot replace the HJHS; however, it can serve as an imaging examination complementing HJHS 2.

Electroacupuncture ameliorates knee osteoarthritis in rats via inhibiting NLRP3 inflammasome and reducing pyroptosis.

Objective: Knee Osteoarthritis (KOA), is the most common joint disease worldwide. The pathogenesis of KOA is complex and electroacupuncture (EA) is an effective therapy for KOA, but the mechanism remains unclear. In this study, we aim to investigate the potential therapeutic effect of EA on the rat model of KOA induced by monosodium iodoacetate (MIA) and its relationship with NLRP3 inflammasome by immunohistochemistry and western blot. Methods: KOA was induced by intra-articular injection of MIA (3mg/50μL) into the right knee joint of rats. Forty-five male rats weighing 250-300g were randomly divided into 3 groups: control group, KOA group, and KOA + electroacupuncture group (KOA+EA). EA treatment lasted for 2weeks (6 times a week). Paw withdrawal threshold tests were used to assess mechanical allodynia once a week. Safranin O/Fast Green and hematoxylin and eosin (H&E) staining were used to assess the damage to cartilage, synovium, and subpatellar fat pad (IFP). Immunohistochemistry was used to observe NLRP3 inflammasome-associated protein-positive cells in the same field of view and western blot was used to detect the expression of the associated protein in cartilage tissue. Results: The KOA group showed mechanical hyperalgesia, joint inflammation, and significant cartilage tissue destruction. Safranin O/Fast Green and H&E staining revealed that EA alleviated the joint pathological changes caused by KOA and had a protective effect on cartilage, synovium, and IFP destruction. Mechanical allodynia pain and joint swelling were reduced in KOA rats after EA treatment. Immunohistochemistry and western blot showed significant inhibition of NLRP3 inflammasome-associated protein. Conclusion: The results indicate that EA can inhibit NLRP3 inflammasome and reduce pyroptosis, which results in the protection of cartilage tissue and the treatment of KOA. It provides reliable evidence for the development of EA in the treatment of KOA and the clinical application of acupuncture.

Regulating Th17/Treg Balance Contributes to the Therapeutic Effect of Ziyuglycoside I on Collagen-Induced Arthritis

To investigate the therapeutic effect and primary pharmacological mechanism of Ziyuglycoside I (Ziyu I) on collagen-induced arthritis (CIA) mice. CIA mice were treated with 5, 10, or 20 mg/kg of Ziyu I or 2 mg/kg of methotrexate (MTX), and clinical manifestations, as well as pathological changes, were observed. T cell viability and subset type were determined, and serum levels of transforming growth factor-beta (TGF-β) and interleukin-17 (IL-17) were detected. The mRNA expression of retinoid-related orphan receptor-γt (RORγt) and transcription factor forkhead box protein 3 (Foxp3) in mouse spleen lymphocytes was ascertained by the real-time reverse transcriptase-polymerase chain reaction (RT-qPCR). Molecular docking was used to detect whether there was a molecular interaction between Ziyu I and protein kinase B (Akt). The activation of mechanistic target of rapamycin (mTOR) in T cells was verified by Western blotting or immunofluorescence. Ziyu I treatment effectively alleviated arthritis symptoms of CIA mice, including body weight, global score, arthritis index, and a number of swollen joints. Similarly, pathological changes of joints and spleens in arthritic mice were improved. The thymic index, T cell activity, and RORγt production of Ziyu I-treated mice were significantly reduced. Notably, through molecular docking, western blotting, and immunofluorescence data analysis, it was found that Ziyu I could interact directly with Akt to reduce downstream mTOR activation and inhibit helper T cell 17 (Th17) differentiation, thereby regulating Th17/regulatory T cell (Treg) balance and improving arthritis symptoms. Ziyu I effectively improves arthritic symptoms in CIA mice by inhibiting mTOR activation, thereby affecting Th17 differentiation and regulating Th17/Treg balance.

Attenuation of experimental osteoarthritis with human adipose-derived mesenchymal stem cell therapy: inhibition of the pyroptosis in chondrocytes.

To explore the role and mechanism of human adipose-derived mesenchymal stem cells (hAD-MSCs) in the treatment of osteoarthritis (OA). OA hulth model of Sprague Dawley (SD) rats and 20ng/ml TNF-α treated chondrocytes were used as models of OA in vivo and in vitro, respectively. hAD-MSCs were administrated in the articular cavity by injection in vivo and co-cultured with chondrocytes using transwell in vitro. Haematoxylin and eosin staining and Safranin-O/Fast green staining were performed to detect tissue destruction and histopathology. Scanning electron microscopy and transmission electron microscopy were used to observe the ultrastructure of chondrocytes. The pyroptosis signaling pathway-related proteins were detected by immunohistochemistry, immunofluorescence, qRT-PCR and Western blot. And small interference technology was used to study the mechanism in depth. hAD-MSCs could delay the development of rat OA, improve the pathological changes of joints, inhibit the expression of NLRP3, Caspase1, GSDMD and TNFR1. In vitro, the expression of pyroptosis signal proteins in chondrocytes was significantly elevated when stimulated with TNF-α, the level of inflammatory factors such as IL-1β, IL-18 was increased, and the cell morphology was significantly destroyed. While co-cultured with hAD-MSCs, these syndromes were reversed. Knockout of TNFR1 also returned the upregulation of pyroptosis signals which caused by TNF-α. These results demonstrated that hAD-MSCs could inhibit pyroptosis signaling pathway of chondrocytes induced by TNF-α, which have raised our understanding of the role of hAD-MSCs as promising therapy for the management of OA.

Xiong Fu Powder Regulates the Intestinal Microenvironment to Protect Bones Against Destruction in Collagen-Induced Arthritis Rat Models

BackgroundChanges in the intestinal microenvironment affected bone destruction in rheumatoid arthritis (RA), and spleen deficiency (SD) was closely related to the intestinal microenvironment. In this study, we aimed to explore the aggravation of SD on collagen-induced arthritis (CIA) and the bone protection of compound Xiong Fu powder (XFP) on CIA with SD (SD-CIA) based on the intestinal microenvironment.MethodAn SD-CIA rat model was established using Rheum officinale Baill. decoction combined with CIA and then treated with XFP. The aggravating action of SD on CIA rats and the efficacy of XFP were evaluated using AI scores, H&E staining of the joint, and level of serum anti–collagen type II antibody (Col II Ab). Bone destruction was assessed by micro-CT and TRACP staining. In addition, flow cytometry, qRT-PCR, and ELISA were used to evaluate gut mucosal immunity. Moreover, metagenomic sequencing was used to determine the distribution and function of the gut microbiota.ResultsCompared with that in CIA rats, bone destruction in SD-CIA rats was aggravated, as manifested by increased AI scores, more severe joint pathological changes and radiological damage, and increased number of osteoclasts (OCs) in the ankle joint. Meanwhile, the proportion of Tregs/Th17 cells was biased toward Th17 cells in Peyer’s patches. Furthermore, the gene levels of TNF-α, IL-1β, IL-6, and IL-17 were increased. In contrast, the expression of IL-10 and sIgA was decreased in the jejunum and ileum. XFP treatment improved bone damage and intestinal mucosal immune disorders compared with the SD-CIA group. In addition, the distribution and function of the gut microbiota were altered in the SD-CIA group. After XFP treatment, the community and function of the gut microbiota were regulated, manifested as increased abundance of several Lactobacillus species, such as L. acidophilus, which regulates the intestinal Tregs/Th17 cells and quorum sensing pathways, followed by promoting probiotic adhesion to the intestines.ConclusionSD can aggravate bone destruction in CIA rats. Compound XFP may attenuate bone destruction in SD-CIA rats by regulating the intestinal microenvironment. One of the mechanisms is the cross-talk between sIgA secretion regulated by intestinal mucosal Tregs and Th17 cells and adhesion of Lactobacillus mediated by quorum sensing.

Classification of temporomandibular joint internal derangement based on magnetic resonance imaging and clinical findings of 435 patients contributing to a nonsurgical treatment protocol

This prospective clinical study aimed to establish a new classification system for TMJ internal derangement based on MRI in correlation with clinical findings contributing to a nonsurgical treatment protocol. A consecutive sample of 435 internal derangement patients was enrolled in the study. Clinical and MRI studies were used to establish the new classification system. A total of 747 joints were classified according to our staging system and received treatment according to the associated nonsurgical treatment protocol. The primary outcome variables were maximum voluntary mouth opening and visual analogue scale pain scores. The secondary outcome variable was joint sound. Statistical analysis of the differences between pretreatment and posttreatment measurements showed an increase in mouth opening throughout the study period (P < 0.001 at 12 m posttreatment). Statistical analysis of the VAS scores showed a statistically significant decrease in all study groups during all study periods, with P < 0.0001 at 12 months posttreatment. Statistical analysis of joint sounds showed significant improvement during all study periods. The new classification system is a simple, & reasonable including a detailed description of all the pathologic changes of the joint. The nonsurgical treatment protocol was Simple, effective and specific depending on the pathological changes in joint.

Synthesis of naringenin loaded lipid based nanocarriers and their in-vivo therapeutic potential in a rheumatoid arthritis model

Rheumatoid arthritis (RA) is a chronic inflammatory disease of joints with no permanent cure. Although, there are some treatment strategies for RA that can go into remission but a precise treatment strategy is not currently available due to different patient manifestations. In addition, the use of various naturally available anti-inflammatory agents and antioxidants are hampered due to their instability in blood and lack of effective penetration into the synovial fluid. In this study, we aimed to enhance the therapeutic potential of natural but less bioavailable flavonoids by using lipid-based nanocarriers. Three types of lipid nanocarriers including stearic acid (SA), stearic-lauric (SL), and lecithin-chitosan (LC) nanocarriers (with encapsulated naringenin) were prepared by hot melt encapsulation and coprecipitation techniques, respectively. Arthritis in rats was induced by a single injection of complete Freund's adjuvant (CFA) in the sub-planter region of the left hind paw. Thirty six (36) male albino rats were divided into six groups with six animals each. Sole naringenin (NAR) and NAR-loaded lipid NPs (40 mg/kg) were administered orally to treatment groups after 1 h of CFA injection for 28 days continuously. NAR-loaded nanocarriers of spherical shape were synthesized with an average size less than ∼190 nm and zeta potential (<-25 mV for SA and SL, and >+30 mV for LC). We observed the encapsulation efficiency (EE) of 85%, 78% and 81% for LC, SA and SL, respectively. In vitro release of NAR from all nanoformulations showed sustained release behaviour. NAR loaded all lipid nanoformulations significantly (p < 0.001) reduced RA factor, key inflammatory markers, and joint damage than sole NAR. Among all nanocarriers, superior efficacy of SL may be due to synergistic anti-inflammatory effects of the lauric acid. Moreover, HE staining study demonstrated that NAR-loaded NPs significantly suppressed pathological changes of joints and liver tissues. In conclusion, solid lipid nanocarriers and lipid polymer hybrid nanoparticles are proposed here as a safe and effective oral delivery systems to enhance the therapeutic potential of NAR for rheumatoid arthritis treatment. SL carriers were found most effective, followed by LC nanocarriers and SA nanocarriers.

Functional visualization in diseases of the joints: current status and prospects (clinical lecture)

Background. Diseases of the musculoskeletal system (MSS), in particular diseases of joints, are a leading factor for reducing the work ability of the population all around the world. The early diagnosis and treatment for them is a high priority task for clinical medicine. Modern nuclear medicine methods can significantly increase the possibilities in differential diagnostics, optimize treatment and improve the prognosis of diseases of the musculoskeletal system (MOP). Purpose – to study and generalize the world experience of application of modern methods of osteoscintigraphy (OSG) for diagnostics of joints diseases, to define possibilities and prospects of various scintigraphic acquisitions for investigation patients with MSS pathology. Materials and methods. Full-text publications in the databases Scopus, Web of Science Core Collection, PubMed (mostly 2015–2021), international standard guidelines for the diagnosis of MSS pathology and monographs for radionuclide examination methods and hybrid imaging technologies in oncology, orthopedics and traumatology. Results. We received the main approaches for radiological diagnostics of pathological changes in joints and the abilities of osteoscintigraphy. We defined the main principles and analyzed the possibilities and advantages of different nuclear medicine protocols: conventional planar examination of the whole body, 3-phase OSG, single-photon emission computed tomography (SPECT) and combined technology with X-ray computed tomography (SPECT/CT). Indications for the use of OSG in various pathological changes of ORA have been determined. We considered different patterns of radiation imaging according to the pathogenesis of various pathological processes – systemic arthritis, diseases of the joints of the spine, upper and lower extremities. The possibilities of different radiological methods for diagnosing and application of different modes of OSG depending on the pathogenesis and localization of lesions were analyzed and compared. Conclusions. Performing 3-phase OSG and tomographic modes (SPECT, SPECT/CT) significantly increases the efficiency of the method for the diagnostics, determination of process activity, staging and prevalence of joint pathology, as well as for monitoring the treatment results. The method detects active metabolic processes at an early stage in the vascular, soft tissue and bone phases and determines the condition of the joints of the whole body without additional radiation exposure.

Effects of an articular cartilage lubrication with a viscosupplement in vitro and in vivo following osteochondral fractures in horses.

To assess whether the combination of hyaluronan, sodium chondroitin sulfate, and N-acetyl-d-glucosamine (HCSG) lubricates articular cartilage in vitro and modulates joint lubrication in vivo. 16 healthy adult horses. The effects of HCSG injections on SF lubricant properties and joint health, immediately after injury and 2 weeks later, were analyzed by use an equine osteochondral fracture model of post-traumatic osteoarthritis (OA). Middle carpal joints of adult horses were randomly assigned to 1 of 4 surgical treatment groups as follows: normal nonsurgical group (n = 8), normal sham-surgical group (8), OA-induced surgical group with HCSG injection (8), or OA-induced surgical group with saline (0.9% NaCl) solution injection (8). Synovial fluid was aspirated periodically and analyzed for boundary lubrication function and lubricant molecules. At 17 days, joints were screened for gross pathological changes. Induction of OA led to an impairment of SF lubrication function and diminished hyaluronan concentration in a time-dependent manner following surgery, with HCSG injection lessening these effects. Certain friction coefficients approached those of unaffected normal equine SF. Induction of OA also caused synovial hemorrhage at 17 days, which was lower in joints treated with HCSG. After induction of OA, equine SF lubricant function was impaired. Hyaluronan-sodium chondroitin sulfate-N-acetyl-d-glucosamine injection restored lubricant properties at certain time points and reduced pathological joint changes.

Anti-inflammatory and Pro-apoptotic Effects of 18beta-Glycyrrhetinic Acid In Vitro and In Vivo Models of Rheumatoid Arthritis.

18β-Glycyrrhetinic acid (18β-GA), an active component from Glycyrrhiza glabra L. root (licorice), has been demonstrated to be able to protect against inflammatory response and reduce methotrexate (MTX)-derived toxicity. This study was therefore designed to test the therapeutic possibility of 18β-GA on rheumatoid arthritis (RA) and to explore the underlying mechanism. LPS or TNF-α-induced inflammatory cell models and collagen-induced arthritis (CIA) animal models were applied in this study. Real-time quantitative PCR (RT-qPCR) was used to measure the mRNA levels of various cytokines and FOXO family members. The protein levels of molecules in the MAPK/NF-κB signaling pathway were analyzed using western blot. The cell proliferation assay and colony-forming assay were used to test the influence of 18β-GA on cell viability. The cell apoptosis assay and cell cycle assay were performed to detect the effect of 18β-GA on cell proliferative capacity by using flow cytometry. Hematoxylin and eosin (H&E) staining was performed to evaluate pathological changes after drug administration. The enzyme-linked immunosorbent assay (ELISA) was carried out for the detection of cytokines in serum. In vitro, we found that 18β-GA decreased the mRNA levels of IL-1β, IL-6, and COX-2 by inhibiting the MAPK/NF-κB signaling pathway in MH7A and RAW264.7 cell lines. Moreover, 18β-GA was able to suppress cell viability, trigger cell apoptosis, and G1 phase cell cycle arrest in our in vitro studies. 18β-GA dramatically enhanced the mRNA level of FOXO3 in both TNF-α- and LPS-induced inflammation models in vitro. Interestingly, after analyzing GEO datasets, we found that the FOXO3 gene was significantly decreased in the RA synovial tissue as compared to healthy donors in multiple microarray studies. In vivo, 18β-GA exhibited a promising therapeutic effect in a collagen-induced arthritis mouse model by alleviating joint pathological changes and declining serum levels of TNF-α, IL-1β, and IL-6. Finally, we observed that 18β-GA administration could mitigate liver damage caused by collagen or MTX. Collectively, the current study demonstrates for the first time that 18β-GA can inhibit inflammation and proliferation of synovial cells, and the underlying mechanism may be associated with its inhibition of MAPK/NF-κB signaling and promotion of FOXO3 signaling. Therefore, 18β-GA is expected to be a new drug candidate for RA therapy.

Increasing Age Alters the Development of Gait Compensations Following Meniscal Injury in Rats

Osteoarthritis (OA) is characterized by pathological joint changes that progress to pain and disability. Increasing age and joint injury are risk factors for OA. Cartilage becomes less resilient to OA pathogenesis as age increases; however, pain, not cartilage damage, drives patients to seek treatment. Preclinical OA models can help further understanding of the relationship between OA pathogenesis and pain. Joint pain and dysfunction are often associated with motion, making gait a quantitative measure to detect OA-related behavioral changes. Rodents alter gait patterns to correct mechanical instabilities and protect injured limbs, but it is unknown how age affects these changes. We hypothesized gait compensations following meniscal injury in 3-, 6-, and 9-month rats would be affected by age of injury onset. Rats at 3, 6, and 9 months of age received medial collateral ligament transection plus medial meniscus transection (MCLT+MMT) surgery (n = 8/age group) or a skin incision (n = 8/age group). Gait data was collected at 2, 4, 6, and 8 weeks post-surgery using our lab's novel gait technology. After euthanasia, joints were processed for histology. Our results showed both 6- and 9-month MCLT+MMT rats walked with reduced peak vertical forces in their injured limbs immediately after injury (2 weeks post-surgery), and this decreased loading continued as OA progressed (8 weeks post-surgery). At early time points, stance time tended to be increased in MCLT+MMT animals; however, there were no clear trends in spatiotemporal walking patterns across the different age groups. Finally, histology showed significantly worse cartilage damage in the 6- and 9-month MCLT+MMT animals compared to 3-month MCLT+MMT animals. This data demonstrates age of injury affects joint avoidance behaviors and joint dysfunction in a rodent OA model, with older animals selecting to reduce dynamic limb loading while minimizing changes to the timing of steps and position of paws. This work was supported by the National Institutes of Health under grants R01AR068424 and R01AR071335.

Repurposing of Pirfenidone (Anti-Pulmonary Fibrosis Drug) for Treatment of Rheumatoid Arthritis.

Clinical studies have shown that pirfenidone (PFD) effectively relieves joint pain in rheumatoid arthritis (RA) patients. However, the detailed mechanisms underlying the anti-RA effects of PFD have not been investigated. This study was undertaken to investigate the repurposing of PFD for the treatment of RA, and explore its anti-rheumatic mechanisms. A collagen-induced arthritis (CIA) rat model was used to observe joint pathological changes following PFD treatment. Based on bioinformatics to predict the mechanism of PFD anti-RA, using EA. hy926 and TNF-α-induced MH7A cells to establish in vitro model to explore its biological mechanism from the perspectives of synovial inflammation and angiogenesis. PFD significantly relieved pathological changes, including joint swelling, synovial hyperplasia, inflammatory cell infiltration and joint destruction. PFD was also associated with reduced expression of MMP-3 and VEGF in articular chondrocytes and synovial cells of CIA rats (p < 0.05). Using bioinformatic methods, we predicted that PFD inhibits cell inflammation and migration by interfering with the JAK2/STAT3 and Akt pathways. These results were verified using in vitro models. In particular, PFD effectively reduced the expression of pro-inflammatory, chondrogenic, and angiogenic cytokines, such as IL-1β, IL-6, IL-8, MMP-1/3/2/9 and VEGF (p < 0.05), in TNF-α-induced MH7A cells. In addition, PFD significantly reduced the production of MMP-2/9 and VEGF in EA. hy926 cells, thereby weakening migration and inhibiting angiogenesis (p < 0.05). These findings suggest that PFD may alleviate the pathological process in CIA rats, by inhibiting inflammation and angiogenesis through multiple pathways, and serve as a potential therapeutic drug for RA.

Qingluoyin granules protect against adjuvant-induced arthritis in rats via downregulating the CXCL12/CXCR4-NF-κB signalling pathway

Context Qingluoyin (QLY) is a traditional Chinese medicine (TCM) formula which has been used in treating human rheumatoid arthritis (RA) for years in China. Objective This study investigates the effect of QLY granules on adjuvant arthritis (AA) and the possible mechanism. Materials and methods Sprague-Dawley (SD) rats were injected with Complete Freund’s adjuvant (CFA) to induce the AA model. After the onset of arthritis, rats received intragastric administrations of the QLY granules (1.35, 2.70, and 5.40 g/kg) or Tripterygium glycosides (TG) tablets (positive drug, 10 mg/kg) for 14 d. After 28 d immunization, the symptoms, inflammatory parameters and molecular mechanisms were investigated. Results In the QLY granule (1.35, 2.70, and 5.40 g/kg) therapy groups, the arthritis index decreased to 6.30 ± 2.06, 5.80 ± 1.55, 5.30 ± 1.16 compared with the model (9.00 ± 3.01), paw swelling decreased to 1.56 ± 0.40, 1.28 ± 0.38, 1.12 ± 0.41 mL compared with the model (2.22 ± 0.73 mL). QLY granules (1.35, 2.70 and 5.40 g/kg) significantly reduced the thymus and the spleen indexes, inhibited the production of pro-inflammatory cytokines, and alleviated the pathological changes of joints compared with the model group. Furthermore, the treatment of QLY granules (2.70 and 5.40 g/kg) markedly inhibited CXCL12, CXCR4 (in spleen and synovium) and p-NF-κB p65 (in synovium) protein expression of AA rats. Conclusions QLY granules have obvious therapeutic effects on AA rats, which may be associated with downregulating the CXCL12/CXCR4-NF-κB signalling pathway. QLY granules can be used as a candidate for the treatment of RA, which deserves further study.

The Protective Effects of the Ethyl Acetate Part of Er MiaoSan on Adjuvant Arthritis Rats by Regulating the Function of Bone Marrow-Derived Dendritic Cells

Aims. The aim of this study was to evaluate the protective effects of Er Miao San (EMS) and the regulative function of bone marrow-derived dendritic cells (BMDCs) on adjuvant arthritis (AA) in rats. Methods. The ethyl acetate part of EMS (3 g/kg, 1.5 g/kg, and 0.75 g/kg) was orally administered from day 15 after immunization to day 29. The polyarthritis index and paw swelling were measured, the ankle joint pathological changes were observed using hematoxylin-eosin (HE) staining, and the spleen and thymus index were determined. Moreover, T and B cell proliferation were determined using the CCK-8 assay. The expression of BMDC surface costimulatory molecules and inflammatory factors were determined using flow cytometry and ELISA kits, respectively. Results. Compared with the AA model rats, the ethyl acetate fraction of EMS obviously reduced paw swelling (from 1.0 to 0.7) and the polyarthritis index (from 12 to 9)P&lt;0.01and improved the severity of histopathologyP&lt;0.01. The treatment using ethyl acetate fraction of EMS significantly reduced the spleen and thymus indexP&lt;0.01and inhibited T and B cell proliferationP&lt;0.01. Moreover, EMS significantly modulated the expression of surface costimulatory molecules in BMDCs, including CD40, CD80, CD86, and major histocompatibility complex class II (MHC-II)P&lt;0.01. The results also showed that the ethyl acetate part of EMS significant inhibited the levels of proinflammatory cytokines interleukin- (IL-) 23 tumor necrosis factor- (TNF-) α and inflammatory factor prostaglandin (PG) E2 in the supernatant of BMDCs. However, the level of anti-inflammatory cytokine IL-10 was significantly increasedP&lt;0.01. Conclusion. These results suggest that the ethyl acetate part of EMS has better protective effects on AA rats, probably by regulating the function of BMDCs and modulating the balance of cytokines.

Effect of high fat diet and excessive compressive mechanical force on pathologic changes of temporomandibular joint

The aim of this study was to investigate the effect of high fat diet and excessive compressive mechanical force on temporomandibular joint. In vivo, a mouse model of temporomandibular joint compressive loading device was used. A high fat diet mouse model and a combined mouse model intraperitoneally treated with or without simvastatin were used in the study. The pathological changes of mandibular condylar cartilage were assessed by Safranin-O staining. The IL-1β, MMP-3, leptin expression changes in the cartilage were detected by immunohistochemistry. In vitro, the mandibular condylar chondrocytes were treated with or without L-1β and simvastatin. The mRNA expression level of matrix MMPs and leptin were assessed. Both excessive compressive mechanical force and high fat diet induced obesity caused TMJ osteoarthritis-like changes and increased expression of IL-1β, MMP-3, and leptin. These pathological changes were much more serious when the two interventions were exerted together, while simvastatin could obviously alleviate these changes. The mRNA expression of MMP-3, MMP-13, and leptin increased in the IL-1β treated chondrocytes treated with IL-1β, and decreased with simvastatin treatment. The development of temporomandibular joint pathological changes could be caused by the excessive compressive mechanical force and high fat diet induced obesity.

Inhibition of Histone Deacetylase 6 by Tubastatin A Attenuates the Progress of Osteoarthritis via Improving Mitochondrial Function

Because chondrocytes are the only resident cells in articular cartilage, the steady state of these cells is important for the maintenance of joint function. In various osteoarthritis diseases, chondrocytes undergo a series of pathophysiologic changes, leading to the loss of chondrocytes and the degradation of extracellular matrix (ECM). This study found that Cytoplasmic localized histone deacetylase 6 (HDAC6) is up-regulated on the articular surface in a destabilization of the medial meniscus-induced mouse osteoarthritis model. Because HDAC6 is highly related to the acetylation of tubulin and the function of the microtubule system is closely related to material transport and signal transduction, the relationship between the expression level or activity of HDAC6 and the fate of chondrocytes invitro and invivo were confirmed. Primary chondrocytes overexpressing DNA-HDAC6 with plasmid were constructed invitro, and HDAC6 inhibitor Tubastatin A was selected to inhibit HDAC6 enzyme activity invivo and invitro. Subsequently, mitochondrial spatial arrangement, degradation of ECM, and pathological changes in joint were defined. The results indicate that overexpression of HDAC6 causes mitochondrial dysfunction and promotes reactive oxygen species production, leading to degradation of ECM. Tubastatin A treatment after osteoarthritis ameliorates the degradation of cartilage and improves the microenvironment and function of the joint. HDAC6 may be targeted to treat osteoarthritis.

Deficiency of β-arrestin2 exacerbates inflammatory arthritis by facilitating plasma cell formation.

β-arrestin2 (β-arr2) is, a key protein that mediates desensitization and internalization of G protein-coupled receptors and participates in inflammatory and immune responses. Deficiency of β-arr2 has been found to exacerbate collagen antibody-induced arthritis (CAIA) through unclear mechanisms. In this study we tried to elucidate the molecular mechanisms underlying β-arr2 depletion-induced exacerbation of CAIA. CAIA was induced in β-arr2-/- and wild-type (WT) mice by injection of collagen antibodies and LPS. The mice were sacrificed on d13 after the injection, spleen, thymus and left ankle joints were collected for analysis. Arthritis index (AI) was evaluated every day or every 2 days. We showed that β-arr2-/- mice with CAIA had a further increase in the percentage of plasma cells in spleen as compared with WT mice with CAIA, which was in accordance with elevated serum IgG1 and IgG2A expression and aggravating clinical performances, pathologic changes in joints and spleen, joint effusion, and joint blood flow. Both LPS stimulation of isolated B lymphocytes in vitro and TNP-LPS challenge in vivo led to significantly higher plasma cell formation and antibodies production in β-arr2-/- mice as compared with WT mice. LPS treatment induced membrane distribution of toll-like receptor 4 (TLR4) on B lymphocytes, accordingly promoted the nuclear translocation of NF-κB and the transcription of Blimp1. Immunofluorescence analysis confirmed that more TLR4 colocalized with β-arr2 in B lymphocytes in response to LPS stimulation. Depletion of β-arr2 restrained TLR4 on B lymphocyte membrane after LPS treatment and further enhanced downstream NF-κB signaling leading to additional increment in plasma cell formation. In summary, β-arr2 depletion exacerbates CAIA and further increases plasma cell differentiation and antibody production through inhibiting TLR4 endocytosis and aggravating NF-κB signaling.

Stem-Cell Derived Exosomes for the Treatment of Osteoarthritis.

Osteoarthritis(OA) is a common degenerative orthopedic disease with multiple pathologic changes in joints affecting large populations worldwide. No treatment can reverse the progress of OA. Since exosomes were first reported in 1983, researches have been conducted to explore the mechanisms and therapeutic potential of exosomes in treating OA. Exosomes derived from Mesenchymal stem cells have attracted increasing attention in tackling the disease. This article summarizes the current advances and challenges in exosomes for OA, which may providea reference for further research.