Rat Model Of Arthritis Research Articles

Inhibition of Spinal Interleukin-33 Attenuates Peripheral Inflammation and Hyperalgesia in Experimental Arthritis.

Accumulating evidence indicates that the continuous and intense nociceptive from inflamed tissue may increase the excitability of spinal dorsal horn neurons, which can signal back and modulate peripheral inflammation. Previous studies have demonstrated that spinal interleukin (IL)-33 contributes to the hyperexcitability of spinal dorsal horn neurons. This study was undertaken to investigate whether spinal IL-33 can also influence a peripheral inflammatory response in a rat model of arthritis. Lentivirus-delivered short hairpin RNA targeting IL-33 (LV-shIL-33) was constructed for gene silencing. Rats with adjuvant-induced arthritis (AIA) were injected intrathecally with LV-shIL-33 3days before the complete Freund's adjuvant (CFA) injection. During an observation period of 21days, pain-related behavior and inflammation were assessed. In addition, the expression of spinal proinflammatory cytokines and the activation of spinal extracellular signal-regulated kinase (ERK) and nuclear factor-κB (NF-κB) pathways were evaluated on 9days after CFA treatment. The existence of tissue injury or inflammation in rats with AIA resulted in the upregulation of spinal IL-33, which is predominantly expressed in neurons, astrocytes, and oligodendrocytes. Intrathecal administration of LV-shIL-33 significantly alleviated hyperalgesia, paw swelling, and joint destruction, and attenuated the expression of proinflammatory cytokines [IL-6, IL-1β, and tumor necrosis factor-α (TNF-α)], as well as the activation of ERK and NF-κB/p65 in the spinal cord. Our data suggest that spinal IL-33 contributes to the development of both peripheral inflammation and hyperalgesia. Thus, interference with IL-33 at the spinal level might represent a novel therapeutic target for painful inflammatory disorders.

Wu-Teng-Gao External Treatment Improves Th17/Treg Balance in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) represents the consequence of an immune response of the body's immune system attacking healthy cells. This chronic inflammatory disorder has complicated pathogenesis. Traditional Chinese medicine (TCM) is well recognized as an effective therapy in treating RA and has been widely applied for centuries. Wu-Teng-Gao (WTG) is used as a representative natural herb formula in RA treatment in China, while its mechanisms are to be fully clarified. The present study attempted to explore mechanisms of WTG on RA treatment in a network pharmacological approach and verified using experiments in vitro. Following the establishment of a rat model of collagen-induced arthritis (CIA), WTG was applied externally on the metapedes of rats. HE staining was subsequently performed to visualize the pathological changes of synovium and bone. Simultaneously, flow cytometry was conducted to detect the cell ratio of T helper 17 (Th17) and Regulatory T cells (Treg) in splenic lymphocytes. Additionally, ELISA, qRT-PCR, and Western blot assays were adopted to determine expressions of RA-related factors in joints and serum. Results of network pharmacological analysis suggested that Th17 cell differentiation might serve as a potential signaling pathway of WTG therapy for RA. Animal experiments demonstrated that WTG ameliorated the articular inflammation and effectively inhibited the destruction of articular cartilage, and decreased Th17 and Treg cell ratios in CIA rats. Furthermore, WTG also greatly suppressed relevant levels of inflammatory cytokines (IL-17, TNF-α, IL-1, and IL-6) and RNAKL, whereas it elevated expressions of anti-inflammatory cytokines IL-10 and TGF-β. Our results confirmed that WTG might improve the imbalance of Th17/Treg cells in CIA animals through differentiation regulation, thus alleviating joint inflammation and bone destruction.

Pterostilbene exert an anti-arthritic effect by attenuating inflammation, oxidative stress, and alteration of gut microbiota.

Pterostilbene is a revesterol analog with a long bioavailability and having potent anti-inflammatory activity in animal studies. In this study, we tried to scrutinize the anti-arthritic effect of pterostilbene against complete Freund's adjuvant (CFA)-induced arthritis model in rats. CFA was used for induction of the RA, and rats were divided into groups depending on different doses of pterostilbene given. Hepatic, antioxidant, rheumatoid factor (RF), myeloperoxidase (MPO), inflammatory cytokines, anti-collagen(C)II-Ig, inflammatory mediators, and gut microbiota were estimated. Pterostilbene significantly (p<.001) decreased the paw swelling, arthritic score, and increased the body weight. Besides altered the antioxidant, inflammatory mediators, anti-collagen (C)II Ig, and inflammatory cytokines. Furthermore, pterostilbene treatment helps to restore the ecosystem of gut microbiota in rats by reducing the relative abundance of Helicobacter, Desulfovibrio, Lachnospiraceae, and Mucispirillium. Based on the findings, we can say that pterostilbene has an anti-arthritic effect via suppressing inflammatory responses and altering intestinal bacteria. PRACTICAL APPLICATIONS: Arthritis is the painful disease and affected most of the people worldwide. In this experimental study, we estimated the anti-arthritic effect of pterostilbene against CFA-induced arthritis in rats. Pterostilbene noticeably suppressed the paw thickness, arthritic score, and organ index. Pterostilbene substantially altered the oxidative stress and inflammatory reaction. Pterostilbene considerably modulated the gut microbiota, suggesting the anti-arthritic effect.

Anti-Gout Effects of the Medicinal Fungus Phellinus igniarius in Hyperuricaemia and Acute Gouty Arthritis Rat Models.

Background: Phellinus igniarius (P. igniarius) is an important medicinal and edible fungus in China and other Southeast Asian countries and has diverse biological activities. This study was performed to comparatively investigate the therapeutic effects of wild and cultivated P. igniarius on hyperuricaemia and gouty arthritis in rat models. Methods: UPLC-ESI-qTOF-MS was used to identify the chemical constituents of polyphenols from wild P. igniarius (WPP) and cultivated P. igniarius (CPP). Furthermore, WPP and CPP were evaluated in an improved hyperuricaemia rat model induced by yeast extract, adenine and potassium oxonate, which was used to examine xanthine oxidase (XO) activity inhibition and anti-hyperuricemia activity. WPP and CPP therapies for acute gouty arthritis were also investigated in a monosodium urate (MSU)-induced ankle swelling model. UHPLC-QE-MS was used to explore the underlying metabolic mechanisms of P. igniarius in the treatment of gout. Results: The main active components of WPP and CPP included protocatechuic aldehyde, hispidin, davallialactone, phelligridimer A, hypholomine B and inoscavin A as identified by UPLC-ESI-qTOF-MS. Wild P. igniarius and cultivated P. igniarius showed similar activities in reducing uric acid levels through inhibiting XO activity and down-regulating the levels of UA, Cr and UN, and they had anti-inflammatory activities through down-regulating the secretions of ICAM-1, IL-1β and IL-6 in the hyperuricaemia rat model. The pathological progression of kidney damage was also reversed. The polyphenols from wild and cultivated P. igniarius also showed significant anti-inflammatory activity by suppressing the expression of ICAM-1, IL-1β and IL-6 and by reducing the ankle joint swelling degree in an MSU-induced acute gouty arthritis rat model. The results of metabolic pathway enrichment indicated that the anti-hyperuricemia effect of WPP was mainly related to the metabolic pathways of valine, leucine and isoleucine biosynthesis and histidine metabolism. Additionally, the anti-hyperuricemia effect of CPP was mainly related to nicotinate and nicotinamide metabolism and beta-alanine metabolism. Conclusions: Wild P. igniarius and cultivated P. igniarius both significantly affected the treatment of hyperuricaemia and acute gouty arthritis models in vivo and therefore may be used as potential active agents for the treatment of hyperuricaemia and acute gouty arthritis.

Design of Targeted Flurbiprofen Biomimetic Nanoparticles for Management of Arthritis: In Vitro and In Vivo Appraisal.

Flurbiprofen (FLUR) is a potent non-steroidal anti-inflammatory drug used for the management of arthritis. Unfortunately, its therapeutic effect is limited by its rapid clearance from the joints following intra-articular injection. To improve its therapeutic efficacy, hyaluronic acid-coated bovine serum albumin nanoparticles (HA-BSA NPs) were formulated and loaded with FLUR to achieve active drug targeting. NPs were prepared by a modified nano-emulsification technique and their HA coating was proven via turbidimetric assay. Physicochemical characterization of the selected HA-BSA NPs revealed entrapment efficiency of 90.12 ± 1.06%, particle size of 257.12 ± 2.54 nm, PDI of 0.25 ± 0.01, and zeta potential of −48 ± 3 mv. The selected formulation showed in-vitro extended-release profile up to 6 days. In-vivo studies on adjuvant-induced arthritis rat model exhibited a significant reduction in joint swelling after intra-articular administration of FLUR-loaded HA-BSA NPs. Additionally, there was a significant reduction in CRP level in blood as well as TNF-α, and IL-6 levels in serum and joint tissues. Immunohistochemical study indicated a significant decrease in iNOS level in joint tissues. Histopathological analysis confirmed the safety of FLUR-loaded HA-BSA NPs. Thus, our results reveal that FLUR loaded HA-BSA NPs have a promising therapeutic effect in the management of arthritis.

Cell-free DNA depletion via cell-penetrating poly(disulfide)s for rheumatoid arthritis therapy

Cell-free DNA (cfDNA)-induced inflammation is linked to various autoimmune diseases, though cfDNA scavenging for cationic polymers has been regarded as an efficient therapeutic pathway. However, most existing cfDNA scavengers have significant cytotoxicity and weakly binds to cfDNA. Here, an advanced cfDNA scavenging strategy via assembly of cfDNA is reported for rheumatoid arthritis (RA) therapy. In this study, we developed a pH-responsive calcium carbonate nanoplatform loaded with low-toxicity guanidinium-containing cell-penetrating poly(disulfide)s (CPDs, LA). The LA could strongly adhere to nucleic acid (NA) and further self-assemble into NA nanospheres. Importantly, the NA nanospheres could be directly delivered into the cell through thiol-mediated uptake, which avoided the activation of the endosomal toll-like receptors (TLRs), thereby inhibited CpG-activated inflammation. As a result, LA@CaCO3 effectively decreased the cfDNA level and alleviated the joint swelling and bone erosion on a collagen-induced arthritis (CIA) rat model of RA. Accordingly, the study proposes an advanced approach to deplete NA for autoimmune disease treatment.

Anti-arthritic activity of the flavonoids fraction of ivy leaves (Hedera helix L.) standardized extract in adjuvant induced arthritis model in rats in relation to its metabolite profile using LC/MS.

Ivy leaves (Hedera helix) is a traditional plant used for common cold, cough, and bronchial disorders and can be used for rheumatoid arthritis (RA) as an attempt in alternative medicine. RA is a chronic autoimmune disease characterized by its increasing frequency and adverse consequences. There is an urgent need for a long-term therapy that has favorable biological effects and is less expensive than the already authorized synthetic medicines. This study aimed to determine the anti-arthritic potentials of Hedera helix with determination of the bioactive fraction and discovery of its second-generation metabolites by means of LC/MS. The total ivy ethanolic extract (TIE-E), saponins fraction (Sap-F) and flavonoids fraction (Flav-F) were investigated for their in-vitro anti-arthritic effects and in-vivo by Adjuvant-induced arthritis (AIA) using Complete Freund's Adjuvant (0.1mL, CFA) intradermal relative to the usual dose of ibuprofen (5mg/kg). We examined the physical alterations, rheumatoid biomarkers, cytokines that cause and inhibit inflammation, markers of oxidative stress, hyaluronidase and β-glucuronidase enzyme activity. Each paw's histopathology was also evaluated. The chemical profiles of TIE-E were studied using LC/MS in both positive and negative ionization modes. TIE-E (200mg/kg) and Flav-F (100mg/kg) significantly (P< 0.05) lowered the edema of the paws, serum immunological indicators, inflammatory cytokines, degenerative enzymes, and indicators of reactive oxygen species with increasing in the anti-inflammatory cytokines. Our findings suggest that extracts of ivy leaves might be used effectively to treat rheumatoid arthritis, where its flavonoid content is responsible for that, and it is able to repress biochemical, oxidative, and pathological changes associated with (AIA) Adjuvant-induced arthritis.

Anti-inflammatory effect of Eucommia Chlorogenic Acid (ECA) on adjuvant-induced arthritis rats and its effect on autophagy related pathway

Observation ECA’s treatment effects in Adjuvant arthritis rats and relative mechanisms. The rat model of arthritis was established by subcutaneous injection of 0.2 mL Freund’s complete adjuvant. After model success, giving different ECA concentrations (25 mg/kg, 50 mg/kg and 100 mg/kg) to rats by ig methods and continued to 28 days. Measuring thymus and spleen index; observation histopathological morphology of rat joint by HE and Masson staining, and Inflammatory cells, synovial hyperplasia, oochas score and degree of fibrosis were detected semi quantitatively. The relative gene and protein expressions were measured by RT-PCR and Western blot. Compared with Normal group, Inflammatory cells, synovial hyperplasia, fibrosis and oochas score increased significantly in Model group (P<0.01, respectively); COX-1, COX-2, TNF-α, IL-1β, IL-6 and IL-17 mRNA expression were significantly up-regulation (P<0.01); AMPK, Beclin1 and ATG12 mRNA and protein expressions were significantly down-regulation (P<0.01, respectively). Compared with Model group, The inflammatory cells, the degree of fibrosis, the proliferation of synovial tissue and OOCHAS score decreased significantly in Middle and High groups (P<0.01, respectively); Thymus index significantly depressed in Low, Middle and High groups (P<0.01, respectively); spleen index were significantly down-regulation in Middle and High groups (P<0.05 or P<0.01); COX-2, TNF-α and IL-17 mRNA expression was significantly down-regulation (P<0.05), IL-1βand IL-6 mRNA expression were significantly depressed in Middle and High groups (P<0.05 or P<0.01); AMPK, Beclin1, LC3-II, ATG5 and ATG7 mRNA expressions were significantly up-regulation in Middle and High groups (P<0.05 or P<0.01); mTOR gene expression was significantly down-regulation (P<0.05), ATG12 mRNA expression was significantly up-regulation (P<0.01) in High group; AMPK, Beclin1, LC3-II, ATG5 and ATG7 protein expressions were significantly increased in High group (P<0.05 or P<0.01), mTOR protein expression were significantly down-regulation and ATG12 protein expression were significantly up-regulation in Low, Middle and High groups (P<0.05 or P<0.01, respectively). ECA can inhibit the inflammatory response in adjuvant arthritis rats, and its mechanism may be related to promoting autophagy of synovial cells.

Effect of Nerve Training Technology on Apoptosis of Cartilage and Osteoblasts and Expression of Aggrecan Protein in Osteoporotic Arthritis

Arthritis and osteoporosis are two common disorders in the world, especially for the elder, but the current treatments have limited efficacy. Herein, we aimed to determine whether the novel technique, neurological training can alleviate osteoporosis complicated with arthritis in rat model. Thirty rats were assigned into normal group, model group, and treatment group (treated with forsythin and neurological training) (n = 10) followed by assessment of chondrocytes and osteoblasts using Mankin score, apoptosis by TUNEL and flow cytometry, and IL-1β, TNF-α, and Aggrecan levels. Apoptotic chondrocytes of treatment group (27.43±1.34) was lower than model group (p &lt; 0.05), whereas amount of osteoblast was increased upon forsythin and neurological training, with lower Mankin’s score (6.38±0.76). Besides, the content of IL-1β and TNF-α of treatment group was significantly lower but Aggrecan mRNA and protein expression was significantly higher. In conclusion, neurological training could protect and alleviate osteoporosis complicated with arthritis.

The pharmacological mechanism study of traditional prescription Meng-He Long-Huo-Tang on the treatment of rheumatoid arthritis

A Chinese traditional prescription Meng-He Long-Huo-Tang (LHT) has been used for the treatment of rheumatoid arthritis (RA) for long time, but the pharmacological mechanism is unknown. A collagen-induced arthritis (CIA) rat model was established to study the effects of LHT on CIA rats by recording body weight, paw thickness, arthritis score and peripheral blood analysis. In vitro, rat fresh synovial fibroblasts (SFbs) were extracted, and the effects of LHT on SFbs proliferation, migration and apoptosis were investigated using cell viability and migration assays, gelatin zymography, western blot and immunocytochemistry. In vivo experiments show that LHT can reduce the joint swelling, decrease the levels of MMP-2/9 and inflammatory factors in the blood of CIA rats. In vitro experiments showed that LHT inhibited cell proliferation, migration and promoted apoptosis of activated SFbs. To sum up, this study revealed the underlying mechanism that LHT can effectively alleviate rheumatoid arthritis symptoms by reducing inflammatory factors and inhibiting SFbs excessive proliferation.

Regulation of mi-RNAs Target Cancer Genes Between Exercise and Non-exercise in Rat Rheumatoid Arthritis Induction: Pilot Study.

Introduction:Rheumatoid arthritis is associated with various cancers. Many studies have investigated physical exercise interventions as health improvements to ameliorate the risk of cancer during rheumatoid arthritis diagnosis. Recently, microRNAs were used as biomarkers for health assessment and cancer prediction in rheumatoid arthritis patients.Methods:The effects of exercise interventions on serum microRNAs were investigated in pristane-induced arthritis (PIA) rat models. Twelve Sprague-Dawley male rats were divided into 4 groups including non-exercise without PIA (N-EX), non-exercise with PIA (N-EX + PIA), exercise without PIA (EX) and exercise with PIA (EX + PIA). Blood samples were collected at the end of the study period to analyze miRNA biomarkers and target cancer gene predictions.Results:Four significant Rattus norvegicus (rno-microRNAs) may purpose as tumor suppressors were identified as potential target cancer gene candidate expressions within the 4 comparative interventional exercise groups. One rno-microRNA and target cancer gene candidate was up-regulated and 3 rno-microRNAs and their target cancer genes were down-regulated.Conclusions:Exercise interventions affected rno-miRNAs regulated target cancer gene candidates ITPR3, SOCS6, ITGA6, and NKX2-1 as biomarkers for cancer prognosis in rheumatoid arthritis diagnosis.

Antidepressant Fluoxetine Does Not Appear to Interfere With Key Translational Parameters in the Rat Adjuvant-induced Arthritis Model.

This study aimed to investigate the analgesic effects of fluoxetine on Lewis rats of both sexes in the adjuvant-induced arthritis (AIA) rat model. In humans, chronic pain syndromes typical of rheumatoid arthritis (RA) co-exist with depression which is often treated with fluoxetine antidepressant known to have antinociceptive effects. The experiment was terminated on day 26, after seven days of oral treatment (days 19-25) with fluoxetine and indomethacin. The effects of treatments were assessed on the final day of the study through measuring body weight, serum concentrations of a1-acid glycoprotein, visual arthritis assessment and post mortem histopathology assessment. Statistically significant difference was determined in the body weight of male subjects, with indomethacin-treated animals putting on significantly more weight than the vehicle and fluoxetine-treated counterparts. No differences were found between the different treatment groups in other study assessments. The present study did not provide support for analgesic effects of fluoxetine aimed at reducing the severity of the AIA model.

Network pharmacology-based study of the anti-oxidative mechanism of san miao wan in treatment of arthritis

San Miao Wan (SMW) is a traditional Chinese medicine (composed of Cortex phellodendri, Rhizoma atractylodes, and Radix cyathulae) widely used in China to treat arthritis; however, its underlying mechanism remains unknown. We established the target gene library of SMW and performed gene ontology enrichment analysis of related target genes. The component-target protein-protein interaction (PPI) network of SMW and the disease-target PPI network of arthritis were merged to form a core PPI network. Finally, the anti-oxidative effect of SMW for treating arthritis was evaluated in a rat arthritis model induced by sodium urate. The results showed that R. atractylodes contained four active components with 68 target proteins, R. cyathulae contained two active components and 139 target proteins, and C. phellodendri contained eight active components and 275 target proteins. The target genes of R. cyathulae were highly related to the synthesis and metabolism of reactive oxygen species, while target genes of R. atractylodes and C. phellodendri were highly related to the circulatory system. The component-target PPI network of SMW and the disease-target PPI network of arthritis predominantly overlapped. In vivo, SMW effectively reduced knee swelling induced by sodium urate, decreased serum malondialdehyde levels, and increased serum superoxide dismutase levels. In conclusion, the therapeutic effects of SMW in arthritis are associated with its anti-oxidative properties.

Network pharmacology-based study of the anti-oxidative mechanism of san miao wan in treatment of arthritis

San Miao Wan (SMW) is a traditional Chinese medicine (composed of Cortex phellodendri, Rhizoma atractylodes, and Radix cyathulae) widely used in China to treat arthritis; however, its underlying mechanism remains unknown. We established the target gene library of SMW and performed gene ontology enrichment analysis of related target genes. The component-target protein-protein interaction (PPI) network of SMW and the disease-target PPI network of arthritis were merged to form a core PPI network. Finally, the anti-oxidative effect of SMW for treating arthritis was evaluated in a rat arthritis model induced by sodium urate. The results showed that R. atractylodes contained four active components with 68 target proteins, R. cyathulae contained two active components and 139 target proteins, and C. phellodendri contained eight active components and 275 target proteins. The target genes of R. cyathulae were highly related to the synthesis and metabolism of reactive oxygen species, while target genes of R. atractylodes and C. phellodendri were highly related to the circulatory system. The component-target PPI network of SMW and the disease-target PPI network of arthritis predominantly overlapped. In vivo, SMW effectively reduced knee swelling induced by sodium urate, decreased serum malondialdehyde levels, and increased serum superoxide dismutase levels. In conclusion, the therapeutic effects of SMW in arthritis are associated with its anti-oxidative properties.

Total glucosides of peony induce fibroblast-like synovial apoptosis, and ameliorate cartilage injury via blocking the NF-κB/STAT3 pathway.

BackgroundRheumatoid arthritis (RA) is one of the most common inflammatory arthritis worldwide. Total glucosides of peony (PG) were isolated from Paeonia lactiflora Pall, which were found to have the capacity to intervene in the progression of arthritis via an anti-inflammatory action. This study aimed to explore the protective effect of PG against RA.MethodsIn this study, we further investigated the molecular mechanisms of PG on RA. We constructed RA models by Bovine type II collagen in vitro or complete Freund’s adjuvant (FCA) in vivo. The RA-MH7A cells were cultured and treated with different doses (10, 20, 50 µg/mL) of PG. Cell proliferation, apoptosis, and release of inflammatory cytokines were determined. Furthermore, the effect of PG was also explored in vivo using the collagen-induced arthritis rat model. After 30 days, the rats were sacrificed; histological changes, cytokine level, and protein expression were measured.ResultsIt was revealed that PG dose-dependently inhibited RA-synovial cell growth and induce apoptosis by regulating relative gene level. Besides, PG downregulated the levels of interleukin (IL)-6, tumor necrosis factor-α (TNF-α) and IL-1β, and upregulated IL-10 level in vitro and in vivo. The regulation contributed to the restoration of cartilage injuries. Furthermore, PG also downregulated the expression of nuclear factor-kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) phosphorylation.ConclusionsAll these results showed that PG inhibits the excessive proliferation of synovial cells, and ameliorates cartilage injury via blocking the NF-κB/STAT3 pathway. Collectively, this study provides novel insights into the mechanism of PG, laying a foundation for the application of PG in RA.

Dehydroevodiamine suppresses inflammatory responses in adjuvant-induced arthritis rats and human fibroblast-like synoviocytes

ABSTRACT Dehydroevodiamine (DHE) is an effective natural active substance extracted from Euodiae Fructus, which is a widely used herbal drug in traditional Chinese medicine. The focus of this study was to test the possibility of using DHE in the treatment of rheumatoid arthritis (RA) diseases. A rat model of adjuvant-induced arthritis (AIA) was generated using Complete Freund’s Adjuvant (CFA). Body weight changes, arthritis scores, ankle pathology, tumor necrosis factor-alpha (TNF-α), interleukin-1β(IL-1β), interleukin-6 (IL-6), and interleukin-17 (IL-17) secretion, as well as matrix metalloproteinase (MMP) expression in joint tissue, were measured as indicators of viability of DHE medicated AIA rats. Human fibroblast-like synoviocytes (MH7A cells) were connected to check these impacts. The results confirmed that DHE administration had an excellent therapeutic impact on the AIA rat model, substantially relieving joint swelling, inhibiting synovial pannus hyperplasia, and decreasing joint scores. In addition, the serum enzyme-linked immunosorbent assay (ELISA) showed that DHE treatment reduced the expression of pro-inflammatory factors in AIA rats. The immunohistochemical results showed that DHE treatment could reduce the synthesis of MMPs such as matrix metalloproteinase-1(MMP-1) and matrix metalloproteinase-3 (MMP-3) in the ankle tissue of AIA rats. In vitro, DHE inhibited cell proliferation, mRNA transcription, protein synthesis of proinflammatory factors such as IL-1βand IL-6, and matrix metalloproteinases such as MMP-1 and MMP-3. Furthermore, DHE inhibited the phosphorylation levels of p38, JNK, and ERK proteins in TNF-α-treated MH7A cells.This work assessed the effect of DHE in AIA rats and revealed its mechanism in vitro.

Glycan Activation of Clec4b Induces Reactive Oxygen Species Protecting against Neutrophilia and Arthritis.

Animal models for complex diseases are needed to position and analyze the function of interacting genes. Previous positional cloning identified Ncf1 and Clec4b to be major regulators of arthritis models in rats. Here, we investigate epistasis between Ncf1 and Clec4b, two major regulators of arthritis in rats. We find that Clec4b and Ncf1 exert an additive effect on arthritis given by their joint ability to regulate neutrophils. Both genes are highly expressed in neutrophils, together regulating neutrophil availability and their capacity to generate reactive oxygen species. Using a glycan array, we identify key ligands of Clec4b and demonstrate that Clec4b-specific stimulation triggers neutrophils into oxidative burst. Our observations highlight Clec4b as an important regulator of neutrophils and demonstrate how epistatic interactions affect the susceptibility to, and severity of, autoimmune arthritis.

Transplantation of IL-1β siRNA-modified bone marrow mesenchymal stem cells ameliorates type II collagen-induced rheumatoid arthritis in rats.

Rheumatoid arthritis (RA) is a chronic autoimmune disease that causes erosion of articular cartilage and bone and has adverse effects on both patients and livestock animals. The aim of the present study was to investigate the role of interleukin-1β (IL-1β) in the pathogenesis of RA, and to further determine whether injection of IL-1β small interfering RNA (siRNA) or transplantation of IL-1β siRNA + bone marrow mesenchymal stem cells (BMSCs) can ameliorate RA in rats. A collagen-induced arthritis (CIA) rat model was established by injecting type II collagen for 4 weeks. Next, CIA rats were randomly divided into three groups and injected or transplanted with PBS, IL-1β siRNA and IL-1β siRNA + BMSCs for another 4 weeks. The CIA rat model was successfully established, as demonstrated by the higher toe swelling value, thymus and spleen/body weight, immobility time and serum IL-1β concentration, as well as lower body weight, climbing time and mRNA expression of programmed death-1 (PD-1), transforming growth factor-β1 (TGF-β1) and forkhead box protein 3 (Foxp3) in the spleen, compared with control rats. Furthermore, histopathology results demonstrated that joint swelling and redness were observed in the knee joints of CIA rats. H&E results revealed that CIA rats presented erosive destruction of the bone and ulceration of the articular cartilage. In addition, in vitro results demonstrated that IL-1β expression was successfully silenced after IL-1β siRNA transfection in lipopolysaccharide-stimulated BMSCs. When compared with the results of PBS rats, both IL-1β siRNA injection and IL-1β siRNA + BMSC transplantation significantly increased the body weight, climbing time and mRNA expression of PD-1, TGF-β1 and Foxp3 in the spleen, while significantly reduced the immobility time and serum IL-1β concentration. In addition, when compared with that of IL-1β siRNA injection, IL-1β siRNA + BMSC transplantation exhibited markedly higher therapeutic efficacy against CIA. These results demonstrated that higher IL-1β contributed to the pathogenesis of CIA, and that IL-1β siRNA injection ameliorated CIA, while its combination with BMSCs exerted synergistic effects, which may be beneficial against RA.

YAP/TAZ: Key Players for Rheumatoid Arthritis Severity by Driving Fibroblast Like Synoviocytes Phenotype and Fibro-Inflammatory Response.

ObjectiveThe role of YAP/TAZ, two transcriptional co-activators involved in several cancers, was investigated in rheumatoid arthritis (RA).MethodsFibroblast like synoviocytes (FLS) from patients with RA or osteoarthritis were cultured in 2D or into 3D synovial organoids. Arthritis rat model (n=28) and colitis mouse model (n=21) were used. YAP/TAZ transcriptional activity was inhibited by verteporfin (VP). Multiple techniques were used to assess gene and/or protein expression and/or localization, cell phenotype (invasion, proliferation, apoptosis), bone erosion, and synovial stiffness.ResultsYAP/TAZ were transcriptionally active in arthritis (19-fold increase for CTGF expression, a YAP target gene, in RA vs. OA organoids; p<0.05). Stiff support of culture or pro-inflammatory cytokines further enhanced YAP/TAZ transcriptional activity in RA FLS. Inhibiting YAP/TAZ transcriptional activity with VP restored a common phenotype in RA FLS with a decrease in apoptosis resistance, proliferation, invasion, and inflammatory response. Consequently, VP blunted hyperplasic lining layer formation in RA synovial organoids. In vivo, VP treatment strongly reduced arthritis severity (mean arthritic index at 3.1 in arthritic group vs. 2.0 in VP treated group; p<0.01) by restoring synovial homeostasis and decreasing systemic inflammation. YAP/TAZ transcriptional activity also enhanced synovial membrane stiffening in vivo, thus creating a vicious loop with the maintenance of YAP/TAZ activation over time in FLS. YAP/TAZ inhibition was also effective in another inflammatory model of mouse colitis.ConclusionOur work reveals that YAP/TAZ were critical factors during arthritis. Thus, their transcriptional inhibition could be relevant to treat inflammatory related diseases.

Novel treatment for refractory rheumatoid arthritis with total glucosides of paeony and nobiletin codelivered in a self-nanoemulsifying drug delivery system.

Patients with refractory rheumatoid arthritis (RA) remain a substantial clinical problem, while the overexpression of P-glycoprotein (P-gp) on their lymphocytes may contribute to resistance to anti-rheumatic drugs. This study aims to develop a novel treatment for refractory RA consisting of the combination of total glucosides of paeony (TGPs) and the P-gp inhibitor nobiletin (N), which are codelivered in a self-nanoemulsifying drug delivery system (SNEDDS). Based on the solubility, compatibility, and pseudoternary phase diagram tests, a nano-SNEDDS formulation composed of capryol 90-cremophor EL35-tcranscutol HP (CET) to codeliver TGP and N was developed, and this formulation increased the bioavailability of TGP by 435.04% (indicated with paeoniflorin). A modified adjuvant-induced arthritis (AIA) rat model was verified for the overexpression of P-gp in lymphocytes and resistance to methotrexate (MTX) treatment at the reported anti-inflammatory dosage. CET formulation not only increased the solubility and permeability of TGP but also inhibited the function and expression of P-gp, leading to enhanced bioavailability and intracellular concentration in the lymphocytes of AIA rats and consequently boosting the anti-arthritic effects of TGP. Moreover, TGP and N coloaded CET reduced the expression of P-gp in AIA rats partly by inhibiting the phosphorylated AKT and HIF-1α pathways. In summary, TGP-N coloaded SNEDDS is a novel and effective treatment for refractory RA.