Adjuvant-induced Arthritis Group Research Articles

Mesenchymal Stem Cells and Myeloid-Derived Suppressor Cells Interplay in Adjuvant-Induced Arthritis Rat Model

There has not been much researchs on the biological relationship between myeloid-derived suppressor cells (MDSCs) and mesenchymal stem cells (MSCs). The goal of the current work is to examine how these cells cooperate with one another in a rat model of adjuvant-induced arthritis (AIA). Three groups of equal numbers of rats were created; the first group served as the control. Complete Freund's adjuvant (CFA) was injected into the second group to induce AIA. The third group underwent MSCstreatment. Three weeks later, ANA, IL-1β, IL-4, IL-6, IL-10, TNF-α, IFN-γ, M−CSF, iNOS and Arg-1 were determined using ELISA. Flowcytometric studies for MDSCs using CD11bc + and His48 + antibodies were performed. Current results showed significantly higher levels of WBCs, ANA, IL-1, IL-4, IL-6, IL-10, TNF-α, M−CSF, iNOS and Arg-1 along with a significant rise in MDSCs % in the AIA group compared to the control group. As opposed to AIA animals, MSCs administration resulted in a considerable improvement in cytokine levels, supporting the immunomodulation function of MSCs. Histological examination of the joints in the AIA group revealed articular cartilage degradation as well as infiltration of inflammatory cells and fibroplasia. These several evidences suggested that MDSCs may perform various roles in autoimmunity. Understanding how MDSCs and MSCs contribute to arthritis may help their prospective application in immunotherapy. Therefore, the reciprocal collaboration of MSCs and MDSCs must therefore be the subject of new investigations, which can offer new platforms for the development of more effective and individualized therapies for the treatment of immunological illnesses.

Noninvasive Imaging OX40+ Activated T Cells Provides Early Warning of Rheumatoid Arthritis

PurposeThe goal of this study was to develop an imaging probe—IRDye-680RD-OX40 mAb—that can be used for noninvasive imaging and optical imaging of rheumatoid arthritis (RA). OX40/OX40 ligand (OX40L) interactions have been shown to exert potent costimulatory effects on T cell activation. Detectable change in T cell activation profiles was observed in early RA.MethodsOX40 expression pattern was analyzed by flow cytometry. N-hydroxysuccinimide (NHS) esters are used to label proteins selectively on free amino groups of OX40 monoclonal antibody (mAb). Characterization of IRDye-680RD-OX40 mAb was measured and a fluorescence spectrum gathered. Cell binding assay was also performed between activated and naïve murine T cells. Longitudinal near-infrared fluorescence (NIRF) imaging of the probe was performed on day 8, day 9, day 10, and day 11 of adjuvant-induced arthritis (AIA) mouse model. Paw thickness and body weight were compared between the OX40 mAb and IgG injection groups.ResultsNIRF imaging with IRDye-680RD-OX40 mAb revealed strong OX40-positive responses with high specificity. Flow analysis showed that OX40 was specifically expressed on the surface of T cells in RP and spleen of AIA model. The AIA group was significantly differentiated from the control group at all time points with imaging monitoring. The region of interest (ROI) was in line with ex vivo imaging and biodistribution study. This study highlights the potential utility of the OX40 NIRF imaging as a new strategy for RA prediction and T cell monitoring.ConclusionThe results provide evidence that IRDye-680RD-OX40 mAb detects organized T cells activation in early RA. The optical probe was capable of detection of RA pathogenesis. It identified transcriptional responses to RA that mediate its immune functions. Thus, it may be an ideal probe for RA imaging.Graphical

Therapeutic effects of kefir peptides on adjuvant-induced arthritis in rats through anti-inflammation and downregulation of matrix metalloproteinases

AimsRheumatoid arthritis (RA) is a chronic autoimmune disease. Its pathological features are synovial inflammation, bone erosion, and joint structural damages. Our previous studies have shown that kefir peptides (KPs) can reduce cardiovascular disease, osteoporosis and renal inflammation. In this study, we further evaluate the efficacy of KPs on adjuvant-induced arthritis (AIA) in a rat model. Main methodsAfter the 14th day of adjuvant induction, rats were subsequently orally administered KPs (83 or 166 mg/day/kg) or tofacitinib (6.2 mg/day/kg) for 14 days. On the 28th day, the rats were anesthetized with isoflurane for ultrasonic, in vivo imaging system (IVIS), and radiographic imaging and then sacrificed for ankle tissues collection and analysis. In vitro, IL-1β-treated human synovial cells (SW982) were subjected to anti-arthritis mechanism study in the presence of KPs. Key findingsThe results of ultrasonography, radiograph, histology, the expression of matrix metalloproteinases (MMPs), inflammatory cytokines and RANKL/OPG ratio demonstrated decreasing severity of synovitis and bone erosion in the ankle joints after KPs treatment. Activation of the NF-κB and MAPK pathways was significantly reduced in KPs treated AIA group. Furthermore, KPs attenuated IL-1β-induced inflammatory cytokine production and the expression of MMPs in a human synovial cell line SW982. These results demonstrated that KPs alleviated adjuvant-induced arthritis in rats by inhibiting IL-1β-related inflammation and MMPs production. SignificanceWe concluded that KPs can exhibit anti-inflammatory effects by reducing the levels of macrophage-related inflammatory cytokines and MMPs, thus alleviating bone erosion in the ankle joint and constituting a potential therapeutic strategy for rheumatoid arthritis.

Fluorophore-conjugated 4-1BB antibody enables early detection of T-cell responses in inflammatory arthritis via NIRF imaging

PurposeWe first developed a 4-1BB-targeted optical probe, named IRDye-680RD-4-1BB mAb (monoclonal antibody), and evaluated its value for the detection of 4-1BB+ activated T cells in vivo as well as the diagnosis of rheumatoid arthritis (RA) in an adjuvant-induced arthritis (AIA) mouse model.MethodsThe 4-1BB expression pattern was analysed by flow cytometry and immunofluorescence (IF) staining. The 4-1BB mAb was conjugated with IRDye-680RD NHS ester, and characterized via fluorescence spectrum. A cell-binding assay was also performed to assess the interaction of this probe with activated and naïve murine T cells. Longitudinal near-infrared fluorescence (NIRF) imaging of the probe was performed at 6, 24, 48, 72, and 96 h after probe administration.Results4-1BB expression was highly upregulated during the pathogenesis of RA. Good colocalization was also observed between CD3 and 4-1BB by IF staining and t-SNE (T-distributed stochastic neighbour embedding) analysis, which indicates that 4-1BB was mainly expressed on T cells. Compared to the control group, a significantly higher signal was observed in the right hind paw (RP) of mice with AIA at all time points. The ex vivo biodistribution study results were consistent with the in vivo NIRF imaging results, which validated the accuracy of the region of interest (ROI) measurements. The sensitivity against 100% specificity observed in the receiver operator characteristic (ROC) curve analysis could distinguish the AIA group from the control group at all time points, indicating the value of IRDye-680RD-4-1BB mAb for RA diagnosis.ConclusionWe successfully developed a novel optical imaging probe, named IRDye-680RD-4-1BB mAb, for tracking 4-1BB+ activated T cells in vivo, and 4-1BB NIRF imaging is a promising strategy for noninvasively detecting the pathogenesis of RA.

POS0695 EFFECT OF METHOTREXATE AND FOLIC ACID CO-ADMINISTRATION IN ARTHRITIS

BackgroundMethotrexate (MTX) is the recommended first-line treatment for rheumatoid arthritis. Adjuvant-induced arthritis (AIA) rat is a robust model with a high prevalence of arthritis used to investigate arthritis. MTX reduces inflammation, but associated with adverse events, such as gastrointestinal, hepatic, and hematology toxicity (1). To reduce these side effects, folic acid (FA) is administrated at distance to MTX with no defined recommendation for its dosing (5-25mg/week) or time point of administration (2) (1-3 days after MTX application). Whether the complicated therapeutic regimen with MTX once a week and FA at another time point affects compliance is an open question. MTX is metabolized in polyglutamates derivates (MTX-PG), which is a biomarker of MTX efficacy as its half-life (1-4 weeks) is longer than MTX (4h) (3).ObjectivesThe aim of this study was to assess efficacy and tolerance of co-administration of MTX and FA compared to MTX with FA applied one day after MTX in the AIA.MethodsFemale Lewis rat were randomly divided in three groups and received an injection of Mycobacterium butyricum defining day (D) 0 to induce arthritis. An historic AIA group was used as control. Treatment began on D9, one day before arthritis onset in this model. The first group rats were treated with MTX only (n=13), the second group received MTX and FA at the same day (n=14), and the third group received FA one day after MTX administration (n=14). MTX was administrated intraperitoneally (IP) at 1 mg/kg every 3 days (4) and FA was delivered IP at 0.17 mg/kg. Arthritic index (AI) and ankle circumference (AC) were monitored to assess arthritis. Microcomputed tomography of the ankle was performed to assess bone loss. Moreover, complete blood count, transaminases, and MTX-PG were assessed.ResultsArthritis developed at D10 in all groups. AI and AC were similar in MTX groups at the various time points. At D17, arthritis severity was lower in MTX groups (AI (mean and standard deviation): 1.4 ± 1.6; AC: 35 ± 7 mm) compared to AIA historical group (AI: 3.3 ± 0.6; AC: 42 ± 4 mm). Bone erosion and bone loss parameters were similar in all groups. Cortical porosity was around 0.40% ± 0.15 and bone volume / total volume was around 0.22% ± 0.13. MTX-PG1 was found at similar levels in MTX groups and correlated negatively with AI in MTX alone or MTX and FA at the same day groups (p<0.05 and p<0.01, respectively). Finally, white and red blood cells, platelets, hemoglobin, mean corpuscular volume, transaminases, and creatinine were found at a similar level in MTX groups.ConclusionCo-administration of MTX with FA on the same day is effective compared to FA application one day after MTX. MTX metabolism was not affected, as demonstrated by the MTX-PG concentrations. The biological tolerance between the protocols was comparable. Thus, co-administration of MTX and FA seems to be possible and may be more convenient to the patients and improve compliance at the end.

Quantification of joint blood flow by dynamic contrast-enhanced near-infrared spectroscopy: application to monitoring disease activity in a rat model of rheumatoid arthritis.

.Significance: Current guidelines for rheumatoid arthritis (RA) management recommend early treatment with disease modifying antirheumatic drugs (DMARDs). However, DMARD treatment fails in 30% of patients and current monitoring methods can only detect failure after 3 to 6 months of therapy.Aim: We investigated whether joint blood flow (BF), quantified using dynamic contrast-enhanced time-resolved near-infrared spectroscopy, can monitor disease activity and treatment response in a rat model of RA.Approach: Ankle joint BF was measured every 5 days in eight rats with adjuvant-induced arthritis (AIA) and four healthy controls. Arthritis was allowed to progress for 20 days before rats with AIA were treated with a DMARD once every 5 days until day 40.Results: Time and group had separate significant main effects on joint BF; however, there was no significant interaction between time and group despite a notable difference in average joint BF on day 5. Comparison of individual blood flow measures between rats with AIA and control group animals did not reveal a clear response to treatment.Conclusions: Joint BF time courses could not distinguish between rats with AIA and study controls. Heterogeneous disease response and low temporal frequency of BF measurements may have been important study limitations.

Deciphering the chemical profile and pharmacological mechanisms of Baihu-Guizhi decoction using ultra-fast liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry coupled with network pharmacology-based investigation

BackgroundBaihu-Guizhi decoction (BHGZD) has been extensively used for the treatment of rheumatoid arthritis (RA) with a satisfying therapeutic effect. However, the material basis and the underlying mechanisms of BHGZD against RA have not been fully elucidated. PurposeTo investigate the chemical profile and the pharmacological mechanisms of BHGZD against RA. MethodsThe chemical constituents containing in BHGZD were identified using UFLC-Q-TOF-MS/MS system, and the corresponding putative targets were predicted. Then, the differentially expressed genes (DEGs) between adjuvant-induced arthritis (AIA) and normal control groups were identified using microarray analysis. After constructing the interaction network of “RA-related gene-BHGZD putative target”, BHGZD candidate targets against RA were screened by topological analysis and further experimentally validated based on AIA rat model. ResultsA total of 41 chemical constituents were identified in the water extract of BHGZD, which were predicted to hit 1312 putative targets. Additionally, 26 DEGs between the AIA and normal control groups were defined as “RA-related genes”, which were functionally involved into the imbalance of “inflammation-immune” system during RA progression. On the basis of the topological importance in the network of “RA-related gene-BHGZD putative target”, 177 BHGZD candidate targets against RA were identified. Among them, TLR4, c-Fos/AP-1, IL2 and TNF had direct interactions with each other and also function as crucial components of toll-like receptor and T cell receptor signaling pathways, which may play important roles in maintaining the balance of "inflammation-immune" system. Experimentally, we verified that BHGZD dose-dependently attenuated the severity, pathological changes, as well as mechanical, cold, and heat hypersensitivities during RA progression based on the AIA rat model. Further western blot analysis demonstrated that BHGZD significantly reduced the protein levels of TLR4, c-Fos/AP-1, IL2 and TNF, which were induced by RA modeling, in the inflamed joints of AIA rats (all p<0.05). ConclusionThis study combining the chemical and transcriptomic profilings, target prediction, network calculation and experimental validations identifies the chemical constituents containing in BHGZD and offers the convincing evidence that BHGZD may ameliorate RA partially by restoring the balance of "inflammation-immune" system and subsequently reversing the pathological events during RA progression through regulating the TLR4-c-Fos-IL2-TNF axis.

Combined gemfibrozil (peroxisome proliferator-activated receptor alpha agonist) with reduced steroid dose gives a similar management picture as the full steroid dose in a rat adjuvant-induced arthritis model

Objectives: The study aimed to evaluate the efficacy of combined gemfibrozil with prednisolone in the management of adjuvant-induced arthritis (AIA) rat model.Methods: Seventy two adult male Wistar albino rats were divided equally into 1-control group, three diseased groups: 2- Adjuvant induced arthritis (AIA), 3- high fat diet (HF), and 4- combined AIA-HF, and treated groups: 5- gemfibrozil 30 mg/kg treated AIA group (AIA-G) and the combined AIA-HF treated groups: 6- prednisolone equivalent to human 10 mg (AIA-HF-P10), 7- prednisolone equivalent to human 5 mg (AIA-HF-P5) 8- gemfibrozil (HF-AIA-G) and 9- combined treatment (HF-AIA-G-P5)Results: HF diet represents a precipitating factor for knee arthritis. Gemfibrozil improved the inflammatory findings in both AIA and AIA-HF groups. Combined administration of gemfibrozil with reduced steroid dose gave a similar therapeutic effect to the full steroid dose. Fortunately, we reported more reduction in the nuclear factor kappa-B (NF-κB) and high mobility group box 1 (HMGB1) in the HF-AIA-G-P5 compared with the HF-AIA-P10 group. The improvement was proved by the histological findings.Conclusion: Combined reduced prednisolone dose with gemfibrozil potentiates its anti-inflammatory activity. This could be a target in the management of rheumatoid arthritis.

Pharmacokinetics of Morphine in Rats with Adjuvant-induced Arthritis.

We investigated the in vivo dynamics and analgesic effect of morphine using an adjuvant-induced arthritis (AA) rat as a model of chronic inflammation. Morphine generally binds to μ-opioid receptors in the brain to exert its effects. After several minutes, it is metabolized by glucuronidation via a UDP-glucuronosyltransferase (UGT). Here, we showed that in AA rats, UGT activity in liver microsomes was reduced. Morphine-free serum fractions in AA rats were also decreased (control, 84.9%; AA, 63.9%) and the expression of ATP-binding cassette, sub-family B (MDR/TAP), member 1 (ABCB1), which plays a crucial role in morphine bile excretion, decreased to 23.0% that of the control group. However, we observed no significant difference between the AA and control groups regarding blood concentrations of morphine and morphine-3-glucuronide. In contrast, the analgesic effect of morphine increased 4-fold in AA rats. Our results showed that the pharmacokinetics of morphine is not changed, but the pharmacodynamics of morphine is enhanced in chronic inflammation.

Acamprosate Protects Against Adjuvant-Induced Arthritis in Rats via Blocking the ERK/MAPK and NF-κB Signaling Pathway.

Osteoarthritis is a type of joint disease that results from the breakdown of joint cartilage and underlying bone and is believed to be caused by mechanical stress on the joint and low-grade inflammatory processes. Acamprosate significantly ameliorates the pathological features of experimental autoimmune encephalomyelitis due to its anti-inflammatory effect. The aims of the present study were to investigate the anti-arthritis activities of acamprosate and elucidate the underlying mechanisms. Adjuvant-induced arthritis (AIA) was induced by intradermal injection of complete Freund's adjuvant. Male Wistar rats were randomly divided into five groups: (1) sham control group, (2) AIA group, (3) acamprosate 10mg/kg (AIA + ACA10), (4) acamprosate 30mg/kg (AIA + ACA30), and (5) acamprosate 100mg/kg (AIA + ACA100). Paw swelling and the arthritis index were measured, and the production of IL-1β, IL-6, and TNF-α was detected by ELISA in serum. The expression of inflammation-related molecules, including c-Raf, ERK1/2, and NF-κB, was determined by Western blotting. We found that acamprosate significantly suppressed paw swelling and the arthritis index in AIA rats. Moreover, acamprosate also significantly suppressed the production of TNF-α, IL-1β, and IL-6 in serum, which is elevated by AIA induction. Finally, acamprosate inhibited p-c-Raf and p-ERK1/2 and NF-κB activation after AIA treatment. These results indicate that acamprosate has an anti-inflammatory effect on adjuvant-induced arthritic rats via inhibiting the ERK/MAPK and NF-κB signaling pathways, and acamprosate may serve as a promising novel therapeutic agent for osteoarthritis.

Anethole reduces inflammation and joint damage in rats with adjuvant-induced arthritis.

This study evaluated whether anethole attenuates the inflammatory response and joint damage in a model of adjuvant-induced arthritis (AIA) in rats. The animals were treated with 62.5-, 125-, or 250-mg/kg anethole daily for 21days after AIA and necropsied on days 14 and 21 to evaluate the number of serum and synovial leukocytes (total and differential), serum cytokines (IL-2, IL-6, IL-12, IL-17, and TNF-α), and nitric oxide concentrations. Morphologic changes in the cartilage and bone of the femorotibial articulation in both left paw and right paw were studied in hematoxylin/eosin and Sirius Red-hematoxylin sections. Different doses of anethole suppressed paw swelling and the number of serum and synovial leukocytes. However, 250mg/kg of anethole more effectively controlled local and systemic inflammation. Histological evaluation revealed significant prevention of cartilage damage and inflammatory infiltrate scores. Morphometric analysis showed pannus formation, the thickness of the articular cartilage, and bone resorption lower in the anethole-treated AIA group compared to untreated AIA group on both days 14 and 21. These significant anti-inflammatory effects in the anethole-treated AIA group were associated with downregulation of cytokines and nitric oxide levels. Therefore, anethole may be a useful intervention to treat inflammatory arthritis.

Overexpression of aquaporin 4 in articular chondrocytes exacerbates the severity of adjuvant-induced arthritis in rats: an in vivo and in vitro study

BackgroundThe dysfunction of articular chondrocytes is a crucial step in rheumatoid arthritis (RA) pathogenesis while its molecular mechanisms are not fully known. This study was aimed to investigate the expression of aquaporin 4 (AQP4) in articular chondrocytes of adjuvant-induced arthritis (AIA) rats and its involvement in AIA development.MethodsThirty rats were divided into normal and AIA group (n = 15). Rat AIA was induced by intradermal injection of complete Freund’s adjuvant and evaluated by secondary paw swelling and histological assessments on knee joint damage. Localization and protein expression of AQP4 in articular cartilage were examined by immunohistochemistry and western blot. In vitro study, AIA articular chondrocytes were cultured and treated with acetazolamide, an AQPs inhibitor. AQP4 protein level, cell proliferation and mRNA levels of type-II collagen (COII) and aggrecan were measured by western blot, MTT assay and real-time PCR, respectively.ResultsThe results of immunohistochemistry and western blot indicated that AQP4 showed higher protein levels in cartilage tissues of AIA rats than that of normal rats. Correlation analysis revealed that AQP4 protein level in cartilage tissues of AIA rats remarkably correlated positively with secondary paw swelling on day 26 after AIA induction as well as pathological scores on joint damage. Additionally, acetazolamide treatment effectively decreased AQP4 protein level, increased cell proliferation and mRNA levels of COII and aggrecan, suggesting AQP4 inhibition by acetazolamide could normalize the dysfunction of AIA articular chondrocytes in vitro.ConclusionsOur data provide certain experimental evidence that AQP4 over-expression in articular chondrocytes aggravated AIA severity and might be a novel target for RA treatment.

Xitong Wan attenuates inflammation development through inhibiting the activation of nuclear factor-κB in rats with adjuvant-induced arthritis

Ethnopharmacological relevanceXitong Wan (XTW), a traditional Chinese herbs formula, has been used to treat “Bi Zheng” in the clinical practice of traditional Chinese medicine (TCM) for hundreds of years. However, no scientific validation is available on the anti-rheumatic effect of XTW. Aim of studyThis study was carried out to investigate the effects of XTW on joints swelling, joints destruction, production of inflammatory mediators and nuclear factor-κB (NF-κB) activation in rats with adjuvant-induced arthritis (AIA). Materials and methodsAIA was induced by intradermal injection of Complete Freund's adjuvant in the footpad of Wistar rats. Paw volume was measured every 7 days during XTW treatment. Histological score was calculated by hematoxylin and eosin staining. Osteoclast number in articular tissues was counted by tartrate-resistant acid phosphatase staining. Levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 in serum were detected by enzyme-linked immunosorbent assay. Levels of NF-κBp65 and inhibitor of NF-κB (IκB)α in synovium were analyzed by Western blot assay. ResultsCompared with AIA group rats, XTW significantly decreased the paw volume of AIA rats. Meanwhile, XTW significantly reduced the histological score and osteoclast number in articular tissues of AIA rats. In addition, XTW markedly abated the levels of TNF-α, IL-1β and IL-6 in serum, as well as enhanced the level of IκBα in synovium of AIA rats. However, XTW did not show significant effect on the level of p65 in synovium of AIA rats. ConclusionsThese results suggest that XTW attenuates the inflammation development through inhibiting the NF-κB-mediated proinflammatory cytokines production in AIA rats. Our study provides the scientific evidence of XTW on treatment of rheumatoid arthritis in the clinical practice of TCM.

Ameliorative effect and potential mechanism of Ermiao san on adjuvant-induced arthritis in rats

Purpose : To investigate the effect and mechanism of action of Ermiao san (EMS), a traditional Chinese herbal formula, on inflammation development and production of inflammatory mediators in adjuvantinduced arthritis (AIA). Methods : AIA was induced by injection of 0.1 ml Freund’s complete adjuvant (FCA, 10 mg/ml) in the left hind footpad of the rats. AIA rats were intragastricly treated with 0.5, 1, 2 g/kg EMS or 0.1 g/kg methotrexate from day 7 to 28 after FCA challenge. Foot volume and histological score were measured. Osteoclast number was calculated by tartrate-resistant acid phosphatase (TRAP) staining assay. Levels of prostaglandin (PG) E2, tumor necrosis factor (TNF) -α and interleukin (IL)-1β in serum were determined by enzyme-linked immunosorbent assay (ELISA) while the level of nitric oxide (NO) in serum was analyzed by Griess reaction method. Results : Foot volume, histological score, osteoclast number and serum levels of TNF-α, IL-1β, PGE2 and NO were all increased in AIA group rats on day 28 after FCA challenge (all p < 0.01) compared with control. EMS (1 and 2 g/kg) significantly decreased the foot volume of AIA rats by 10 % (p < 0.05) and 19 % (p < 0.01), respectively, compared with AIA group. Furthermore, 1 and 2 g/kg EMS significantly reduced histological score by about 28 % (p < 0.05) and 46 % (p < 0.01), respectively, as well as osteoclast number by 12 % (p < 0.05) and 15 % (p < 0.05), respectively, compared with AIA group. In addition, 1 and 2 g/kg EMS significantly decreased the serum levels of TNF-α about 23 % (p < 0.05) and 43 % (p < 0.01), IL-1β by15 % (p < 0.05) and 26 % (p < 0.01), NO 13 % (p < 0.05) and 26 % (p < 0.01) as well as PGE2 by 11 % (p < 0.05) and 15 % (p < 0.01), respectively, compared with AIA group. Conclusion : These results suggest that EMS probably alleviates arthritis development and joint destruction by decreasing the production of inflammatory mediators in AIA rats. Keywords : Ermiao san, Inflammatory mediators, Adjuvant-induced arthritis, Traditional Chinese medicine, Rheumatoid arthritis

CP-25, a novel compound, protects against autoimmune arthritis by modulating immune mediators of inflammation and bone damage

Paeoniflorin-6′-O-benzene sulfonate (code: CP-25), a novel ester derivative of paeoniflorin (Pae), was evaluated in rats with adjuvant-induced arthritis (AA) to study its potential anti-arthritic activity. AA rats were treated with CP-25 (25, 50, or 100 mg/kg) from days 17 to 29 after immunization. CP-25 effectively reduced clinical and histopathological scores compared with the AA groups. CP-25-treated rats exhibited decreases in pro-inflammatory cytokines (IL-1β, IL-6, IL-17 and TNF-α) coupled with an increase in the anti-inflammatory cytokine TGF-β1 in the serum. CP-25 treatment inhibited M1 macrophage activation and enhanced M2 macrophage activation by influencing cytokine production. Decreases in Th17-IL-17 and the Th17-associated transcription factor RAR-related orphan receptor gamma (ROR-γt) dramatically demonstrated the immunomodulatory effects of CP-25 on abnormal immune dysfunction. In addition, CP-25 suppressed the production of receptor activator of nuclear factor kappa B ligand (RANKL) and matrix metalloproteinase (MMP) 9, which supported its anti-osteoclastic effects. The data presented here demonstrated that CP-25 significantly inhibited the progression of rat AA by reducing inflammation, immunity and bone damage. The protective effects of CP-25 in AA highlight its potential as an ideal new anti-arthritic agent for human RA.

Hyperbilirubinemia decreases physiological markers in adjuvant-induced arthritis.

There is evidence that a higher serum level of bilirubin (BIL) may be a protective factor for autoimmune diseases. We examined the effect of BIL supplementation in adjuvant-induced arthritis (AIA) where oxidative stress, inflammation and inadequate immune response are present. Male Lewis rats were randomized into groups: CO - control, AIA - untreated adjuvant-induced arthritis, AIA-BIL - adjuvant-induced arthritis administrated BIL (200 mg/kg b.w. daily i.p. during 14 days). Change of hind paw volume in the AIA-BIL group in comparison to the AIA group was significantly decreased after BIL administration. In CO and AIA groups we found almost untraceable levels of BIL. In the AIA-BIL group hyperbilirubinemia was observed. BIL administration significantly decreased plasma levels of C-reactive protein and ceruloplasmin in the AIA-BIL group in comparison to the AIA group. The values of white and red blood cells, hemoglobin and hematocrit were significantly decreased in AIA-BIL after BIL supplementation. Organs like spleen and thymus had a lower weight in AIA-BIL than in AIA. Histological findings showed decreased or even absent damage in hind paw joint of AIA-BIL animals. We observed an immunomodulatory effect of BIL on AIA development, which may also have a novel pharmacological impact.

Expression of hedgehog signal pathway in articular cartilage is associated with the severity of cartilage damage in rats with adjuvant-induced arthritis.

BackgroundCartilage damage is a crucial step in rheumatoid arthritis (RA) disease progress while its molecular mechanisms are not fully understood. Here we investigated the expression of hedgehog (Hh) signal pathway in articular cartilage of adjuvant-induced arthritis (AIA) rats and its possible pathological role in cartilage damage.Methods30 rats were divided into sham and AIA group (n = 15). Complete Freund’s adjuvant was used to induce AIA. Secondary paw swelling was measured on day 10, 14, 18, 22 and 26 after induction. Rats were sacrificed on day 26 and knee joints and cartilage tissues were collected. Paw swelling, cartilage histopathologic changes and OARSI scores were used to evaluate AIA in rats. The protein expression of Hh signal related genes (Shh, Ptch1, Smo and Gli1) in cartilage were assayed by immunohistochemistry. The mRNA levels of Shh, Ptch1, Smo, Gli1, type-II collagen (COII) and aggrecan in cartilage were assayed by real-time PCR. In vitro study, cultured AIA chondrocytes were treated with cyclopamine (a specific inhibitor of Hh signal) and the mRNA levels of Hh signal and ECM components (COII and aggrecan) were measured by real-time PCR.ResultsImmunohistochemical results revealed that Shh, Ptch1, Smo and Gli1 proteins showed higher expression in the articular cartilage of AIA rats than those of sham rats. Real-time PCR results confirmed that Shh, Ptch1, Smo and Gli1 mRNA levels in cartilage tissues of AIA rats were significantly increased compared with those of sham rats (1.6, 1.4, 1.6, 2.0 fold, respectively). The mRNA levels of Shh, Ptch1, Smo, and Gli1 were associated with the severity of cartilage damage (indicated by OARSI scores, COII and aggrecan mRNA levels in cartilage). In vitro, cyclopamine effectively decreased the mRNA levels of Shh, Ptch1, Smo and Gli1, and increased the mRNA levels of COII and aggrecan in AIA chondrocytes, suggesting Hh signal inhibition might directly promote ECM production.ConclusionsOur findings present certain experimental evidence that Hh signal pathway is involved in the pathogenesis of cartilage damage in RA.

Ischaemic heart preconditioning in rats with adjuvant-induced arthritis

Adjuvant-induced arthritis (AIA) in rats is a model of chronic systemic inflammation and a model of rheumatoidarthritis in humans. To investigate effectiveness of ischaemic preconditioning (IPC) in reducing the area of myocardial infarction in rats with AIA. The study was performed in vivo in male SPRD/Mol/Lod rats. Animals were assigned to the experimental group (n = 15) or the control group (n = 14). In the experimental group, AIA was induced by subcutaneous administration of 1 mLof Freund's complete adjuvant, and the experiment was performed after 14 days. In control (healthy) animals, no procedures were performed prior to the proper experiment. Animals were anaesthesized (by intraperitoneal administration of ketamineand xylazine) and put on a ventilator. Then, myocardial infarction was induced, preceded by IPC in some animals. To induceinfarction, left main coronary artery (LMCA) was occluded for 30 min, followed by 60 min of reperfusion. IPC protocol consisted of LMCA occlusion for 3 min, followed by 5 min of reperfusion and a second LMCA occlusion for 7 min. Weevaluated a percentage ratio of the infarct size to the risk area (IS/RA). Necrosis area was stained with tetrazolium, and thearea supplied by LMCA was determined using Evans blue. All areas were determined by planimetry. We used nonparametric Kruskal-Wallis rank ANOVA with multiple comparisons, and the results were shown as median values and 25th and 75th percentiles. P < 0.05 was considered statistically significant. In the control group with IPC (n = 7), the IS/RA ratio of 25% (23-38) was significantly reduced compared to thecontrol group without IPC (n = 7) (58% [57-63], p < 0.05). In the AIA group with IPC (n = 7), the IS/RA ratio of 58% (51-65)did not differ significantly compared to the AIA group without IPC (n = 8) (65% [62-71]). Our findings indicate that IPC in rats with AIA does not result in a significant reduction of myocardial necrosisarea induced by 30 min of ischaemia and 60 min of reperfusion. This effect might have been related to the presence ofchronic systemic inflammation. Absent or reduced benefits of IPC may be one reason for an increased cardiovascular risk inpatients with rheumatoid arthritis.

Effect of &lt;i&gt;Aralia chinesis&lt;/i&gt; on serum TNF-a, IL-4 and IL-10 level in rats with adjuvant-induced arthritis

Our study investigated the effect of Aralia chinesis on serum tumor necrosis factor-α (TNF-α), Interleukins (IL-4, IL-10) in rats with adjuvant-induced arthritis. Adjuvant-induced arthritis rats had more slowly increased body weight, dramatically increased TNF-α level but reduced IL-4, IL-10 levels compared with control group. A. chinesis, Tripterygium wilfordii and control group had significantly increased body weight, IL-4, IL-10, and markedly reduced arthritis index and TNF-α level compared with the adjuvant-induced arthritis group. A. chinesis and T. wilfordii group had significantly increased IL-4 and IL-10 levels and markedly reduced TNF-α level compared with control group. A. chinesis could significantly increase the IL-4 level compared with the control group and it can balance the cytokines in arthritis rats, which attributes to the improvement of adjuvant induced arthritis.

Effect of atorvastatin with or without prednisolone on Freund's adjuvant induced-arthritis in rats

Rheumatoid arthritis is a chronic systemic inflammatory disease where cardiovascular diseases have been recognized as major determinants of early morbidity and mortality. Recently, there has been renewed interest in medication with glucocorticoids to decrease joint damage, but in long-term they incur substantial increase in the risk of cardiovascular diseases and their overall risk/benefit ratio is deemed unfavorable. So, the proposed role of statins in treatment of rheumatoid arthritis when corticosteroids indicated as traditional therapy needs to be investigated. Fifty albino rats were divided into 5 equal groups; normal control group, Freund's adjuvant induced arthritis group, group of induced arthritis treated with atorvastatin, group of induced arthritis treated with prednisolone, and group of induced arthritis treated with atorvastatin and prednisolone. The change in paw volume, serum levels of malondialdehyde (MDA), paraoxonase1 (PON1) activity, nitrites, C-reactive protein (CRP) and lipid profile was determined. The results revealed that treatment by atorvastatin in combination with prednisolone produced better satisfactory results than in either remedy alone evidenced by significant decrease in volume of hind paw, levels of MDA, nitrites, CRP, significant increase in PON1 activity and HDL and amelioration of other lipid profile parameters that were impaired by prednisolone. The present work demonstrated that statins exert beneficial anti-inflammatory and antioxidant effects beyond their basic cholesterol-lowering activity. Thus, we suggest that if corticosteroid therapy is indicated in rheumatoid arthritis, atorvastatin could be added to get benefit from its pleiotropic effects. However, further studies are needed to verify to what extent statin therapy contribute to clinical benefits in human.