Effects of Triptolide on the Expression and Activity of NF-κB in Synovium of Collagen-induced Arthritis Rats

Summary： The expression and activity of NF-kB in the synovium of collagen-induced arthritis （CIA） rats was detected in order to investigate the possible therapeutic effects of triptolide on rheumatoid arthritis （RA）. The experimental Wistar rat model of CIA was set up by intradermal injection of emulsion of bovine collagen 11 and the successful rate of setting-up models was evaluated by arthritis index （AI）. Rats were grouped randomly into three groups： normal, model and treatment group. The expression of TNF-α and IL-6 in synovial fluid was detected by ELISA, and the expression and activity of NF kB in synovium by immunohistochemistry method and by electrophoretic mobility shift assay （EMSA） respectively. As compared with normal group, the expression of TNF a and IL-6 in synovia （P〈0. 05）, and the expression and activity of NF-kB （P〈0.05） in synovium were increased in model group. There was statistical difference in above-mentioned indexes between model group and treatment group. Triptolide may play a protective role in IRA via downregulating the expression and activity of NF-kB in synovium.

Prediction of Response of Collagen-induced Arthritis Rats to Methotrexate： An ~1H-NMR-based Urine Metabolomic Analysis

Over one half the patients with rheumatoid arthritis （RA） are being treated with methotrexate （MTX）. Although well proven, the efficacy of MTX varies in individual patients. This study examined the metabolic biomarkers that can be used to predict the therapeutic effect of MTX by using metabolomic analysis. Rats were immunized with collagen to rapidly cause collagen-induced arthritis （CIA） and then treated with 0.1 mg/kg MTX for 4 weeks. The clinical signs and the histopathological features of CIA were observed to evaluate the therapeutic effects. Urine samples of CIA rats were collected, and analyzed by using 600 M 1H-nuclear magnetic resonance （1H-NMR） for spectral binning after the therapy. The urine spectra were divided into spectral bins, and 20 endogenous metabolites were assigned by Chenomx Suite. Multivariate analyses were performed to identify the spectral pattern of endogenous metabolites related to MTX therapy. The results showed that the clustering of the spectra of the urine samples from the responsive rats （n=20） was different from that from the non-responsive rats （n=11）. Multivariate analysis showed difference in metabolic profiles between the responsive and non-responsive rats by using partial least squares-discrimination analysis （PLS-DA） （R2=0.812, Q2=0.604）. In targeted profiling, 13 endogenous metabolites （uric acid, taurine, histidine, methionine, glycine, etc.） were selected as putative biomarkers for predicting therapeutic response to MTX. It was suggested that 1H-NMR-based metabolomic analysis can be used to predict the therapeutic effect of MTX, and several metabolites were found to be related to the therapeutic effects of MTX.

Matrix Metalloproteinase MMP-9 Promotes K/BxN Serum Induced Arthritis in Mice

Matrix metalloproteinases (MMPs) are matrix-degrading enzymes that are over-expressed in joints of rheumatoid arthritis (RA) patients. However, the contribution of specific MMPs for the development of arthritic joints is unknown. This study is aimed at studying the role of matrix metalloproteinase-9 (MMP-9) in mice, using the K/BxN serum-transfer model of RA. Arthritis was induced in Balb/c mice by injecting K/BxN serum. Development of arthritis was followed in these mice by measuring ankle thickness and clinical index score. MMP-9 expression in the joints of mice killed at various time points during the disease progression was determined by gelatin zymography using ankle lysates. We found that MMP-9 expression increased with the severity of arthritis. Importantly MMP-9 deficient mice injected with K/BxN serum showed a milder form of arthritis in comparison to the control C57BL/6 mice injected with K/BxN serum. We therefore conclude that MMP-9 promotes arthritis in mice.

Attenuation of Collagen Induced Arthritis by Centella asiatica Methanol Fraction via Modulation of Cytokines and Oxidative Stress

Objective To investigate the anti-inflammatory, antioxidant and anti-arthritic effects of Centello asiatica methanolfraction （CAME） on collagen-induced arthritis （ClA）, an animal model of rheumatoid arthritis. Methods Arthritis was induced in female wistar rats by immunization with porcine type II collagen. The CIA rats were treated orally with CaME （50, 150, and 250 mg/kg/day） for 15 d （beginning on day 21 of the experimental period）. The clinical, histological, biochemical, and immunological parameters were assessed. Results CaME treatment （150 and 250 mg/kg） significantly attenuated the severity of CIA and reduced the synovial inflammation, cartilage erosion, and bone erosion as evident from both histological and radiographic data. The escalated plasma levels of pro-inflammatory cytokines TNF-α, IL-1β, IL-6, and IL-12 alongwith nitric oxide in CIA rats decreased significantly on CaME treatment. The serum levels of type-Ⅱ collagen antibody were significantly lower in rats of CaME （150 and 250 mg/kg） treated group than those in the arthritic group. Furthermore, by inhibiting the above mediators, CaME also contributed towards the reversal of the disturbed antioxidant levels and peroxidative damage. Conclusion Our results clearly indicate that oral administration of CaME suppresses joint inflammation, cytokine expression as well as antioxidant imbalance, thereby contributing to an amelioration of arthritis severity in CIA rats.

REGULAR EXPRESSION OF DISCOIDIN DOMAIN RECEPTOR 2 IN THE IMPROVED ADJUVANT-INDUCED ANIMAL MODEL FOR RHEUMATOID ARTHRITIS

Objective To investigate the expression of discoidin domain receptor 2 (DDR2) of fibroblast-like synovial cells in im- proved adjuvant-induced animal (AIA) model for rheumatoid arthritis (RA) and to provide evidence for DDR2’s antagonist use clinically. Methods AIA was modified by administrating 0.1 mL of complete Freund’s adjuvant (CFA, mixed with 5 mg Bacillus Calmette-Guerin vaccine/mL) into rats’ right hind paws and 0.125 mL tumor necrosis factor-α (2 U/mL) into right ankles and subpatellar fatty tissue. The expression of DDR2 in fibroblast-like synovial cells was assessed using immunohistochemistry, immunofluorescence histochemistry, and in situ hybridization methods. Levels of anti-collagen II antibody were measured using enzyme-linked immunosorbent assay. Results Given the terms mentioned above, we found a more practical rat model, apparently decreasing immunization time (average 3-5 days). DDR2 can be detected upon the 15th day of immunization; expression gradually increased with time going on, and reaching a peak 35 days after immunization before gradually decreasing. Serum anti-collagen II antibody showed similar expression patterns as DDR2, but reached peak later than DDR2, about 40 days after immunization. Conclusion Regular expression of DDR2 in animal models infers its important role in the pathological process of RA.

Gentiopicroside, originated from Gentiana macrophylla Pall, possesses antiarthritic efficacy in adjuvant-induced arthritis rats

OBJECTIVE This work aimed to investigate the anti-rheumatoid arthritic effect of gentio.picroside from Gentiana macrophylla Pall using an animal model of adjuvant induced arthritis.METH.ODS Adjuvant arthritis was induced in fifty SD male rats,which were randomly divided into five groups(n=10):control(0.5% CMC-Na) group,AIA(rats with CFA) group,dexamethasone(1 mg·kg^(-1)) group,gentiopicroside(50 mg·kg^(-1)) group,and gentiopicroside(100 mg·kg^(-1)) group.Rats were administered intragastrically with drugs or CMC-Na once a day for a period of 2 weeks.Paw swelling,arthritic index,histological changes were assessed to evaluate the anti-arthritic effect.Weight growth,spleen and thymus indexes were also investigated in.RESULTS Gentiopicroside at dose of 100 mg·kg^(-1) significantly inhibited the secondary paw swelling(P<0.05) and arthritis index(P<0.05),decreased synovial inflammatory infil.tration,synovial hyperplasia and bone erosion.Furthermore,gentiopicroside showed no immunosup.pressive adverse effects in body weight,index of spleen and thyums compared with dexamethasone administration(P<0.05,P<0.01).CONCLUSION Gentiopicroside possessed anti-arthritic efficacy in AIA rats without immunosuppressive effects.

The effects of Fumaderm~ on immunological function and cytokines in a rat model of adjuvant-induced arthritis

Objective To study the therapeutic effect of Fumaderm in Freund’s complete adjuvant-induced arthritis(AIA)in Spraque-Dawley rats.Methods Adjuvant-induced arthritis(AIA)was established by intradermal injection of 0.1 mL of Freund’s complete adjuvant(CFA)in the palmar surface of the right hindpaw and Fumaderm was delivered by oral gavage for 28 days.After CFA injection,the edema of the hindpaw was determined every two days.On 28 days after CFA injection,the lymphocyte subsets of peripheral blood and the cytokines were determined by flow cytometry,meanwhile the histopathological examination of ankle-joints of the animals was performed.Results Fumaderm had a significant therapeutic effect on AIA.The hindpaw swelling was reduced significantly in a dose-dependent manner.The ratio of peripheral blood T lymphocytes was improved obviously.Multiparameter cytokine analysis from peripheral blood CD4+ T cells showed a decrease of proinflammatory cytokines and an increase of anti-inflammatory cytokines in Fumaderm treated animals.A strongly reduced inflammatory response in the joint synovium was observed.Conclusion Fumaderm has potential anti-inflammatory effects on AIA rats.Further investigation is needed to elucidate the molecular mechanism involved in the clinical effect observed in the AIA model.

Ginsenoside Rb1 attenuates adjuvant-induced arthritis in rats through inactivation of NF-κB signaling pathway

OBJECTIVE To investigate the anti-arthritic effect and mechanism of action of ginsenoside Rb1 on adju⁃vant-induced arthritis(AIA)in rats.METHODS Male SD rats were received 0.1 mL injections of FCA(10 g·L^-1)emulsion into the right hind metatarsal foot pad for arthritis induction.After that,rats were randomly divided into six groups,namely control group,untreated group,dexamethasone(DEX,2.5 mg·kg^-1)group,low(5 mg·kg^-1),medium(10 mg·kg^-1)and high(20 mg·kg^-1)doses of ginsenoside Rb1 groups,and treated intraperitoneally at the above dosage once a day for 2 weeks.After treatment,paw swelling and arthritis indexes were evaluated,the thymus and spleen index were calculated as well.HE staining were used to observe the joint histopathology in rats.Rat ELISA kits were used to determinate the TNF-α,IL-1βand IL-6 levels.Western blotting were used to detect the related protein expression of NF-κB signaling pathway in the tissues of inflamed joints.RESULTS Rb1 significantly decreased the paw swelling and arthritis index,Compared with AIA group.HE staining results revealed that medium and high doses of Rb1 significantly reduced synovial inflammatory cell infiltration,synovial lining hyperplasia and bone destruction,compared with AIA group.Elisa results showed that Rb1 significantly decreased the TNF-α,IL-1β and IL-6 levels(P<0.05,P<0.01).Western blotting results revealed that the expression of p-IκB and p-P65 were significantly reduced in 20 mg·kg^-1 of Rb1 group,compared with AIA group(P<0.05,P<0.01).CONCIUSION Rb1 manifests therapeutic anti-inflammatory effects on rats with AIA,poten⁃tially through a mechanism of inhibiting activation of the NF-κB.

A novel anti-inflammatory and immunomodulatory drug CP-25 alleviated collagen induced arthritis by down-regulating BAFF-NF-κκB signaling pathway

OBJECTIVE To investigated the regulatory effect of paeoniflorin-6′-O-benzene sulfonate(CP-25) on B cell activating factor(BAFF)/BAFF receptor-nuclear factor of kappa B(NF-κB) signaling in B cell of collagen induced-arthritis(CIA) mice.METHODS Mice CIA was induced by injection of typeⅡcollagen(CⅡ).The arthritis index(AI) and swollen joint count(SJC) were assessed,and histopathology of spleen and joints were observed.The percentage of B cells subsets,BAFF receptor expressions were analyzed by flow cytometry.BAFF and immunoglobulin(Ig) levels were measured by protein antibody array.The expressions of TRAF2,MKK3,MKK6,p-P38,and p-NF-κB65 in NF-κB signaling mediated by BAFF were analyzed by western blot.RESULTS CP-25 decreased AI and SJC,restored abnormal weights,reduced thymus index and spleen index,inhibited T/B cells proliferation,alleviated the histopathology of spleen and joints in CIA mice.CP-25 also reduced high levels of serum BAFF and immunoglobulin,decreased CD19+B cells,CD19+CD27+B cells,and CD19-CD27+CD138+plasma cells,inhibited BAFFR and TACI expressions,decreased the expressions of TRAF2,MKK3,MKK6,p-P38,and p-NF-κB65.Compared with biological agents etanercept and rituximab,CP-25 restored high T cells proliferation and percentages of B subsets to normal level,and recovered the high levels of IgA,IgD,IgG1,IgG2 a and high expressions molecules in NF-κB signaling to normal levels.The action intensity of rituximab and etanercept was more strong than CP-25.The inhibitor effects of rituximab and etanercept on AI and SJC,thymus index,proliferation of T cells and B cells subsets were strong,and down-regulated the indexes to under normal levels.CONCLUSION CP-25 might be a promising anti-inflammatory immune and regulation drug,which alleviated CIA and regulated the functions of B cells through BAFF/BAFF receptor-NF-κB signaling.

Ginsenoside metabolite compound K alleviate collegen-induced arthritis through impairing dendritic cells function

OBJECTIVE Ginsenoside metabolite compound K(CK)is a degradation product of ginsenoside in the intestine by bacteria.The anti-inflammatory and immunomodulatory activities of CK have been reported.This study investigated whether CK exerted its immunoregulatory effect through modulation of dendritic cells(DCs)function.METHODS In vivo,severity of collegen-induced arthritis(CIA),T cells and DCs subsets,phenotype of DC were assayed by flow cytometry,CCL19 and CCL21 level in lymph nodes assayed by ELISA.In vitro,bone marrow-derived DCs from normal mice were matured with lipopolysaccharide and treated with CK for 48 h.In vivo,bone marrow-derived DCs were generated from CIA mice before and 2 weeks into CK treatment.DCs were analyzed for migration,phenotype and T-cell stimulatory capacity.RESULTS CK alleviated the severity of CIA,decreased pD Cs and mo-DCs,increased na?ve T cells in CIA mice lymph nodes,and suppressed CCL21 expression in lymph nodes.CK suppressed DCs migration induced by CCL21 and T cells-stimulatory capability of DC,down-regulated LPS-induced expression of CD80,CD86,MHCII and CCR7 on DCs.CONCLUSION This study elucidated the novel immunomodulatory property of CK via impairing function of DCs in priming T cells activation.These results provide an interesting novel insight into the potential mechanism by which CK contribute to the restoration of immunoregulation in autoimmune conditions.

Is Chemokine Receptor CCR9 Required for Synovitis in Rheumatoid Arthritis? Deficiency of CCR9 in a Murine Model of Antigen-Induced Arthritis

Objectives: Monocytes/macrophages accumulate in the synovial membrane in rheumatoid arthritis and play a key role in disease pathogenesis, contributing to inflammation, cartilage destruction and bone erosion. Identification of molecules involved in monocyte/macrophage recruitment in inflammation is crucial for development of therapeutic interventions. Chemokine receptor CCR9 is up-regulated on these cells in peripheral blood and synovium of rheumatoid patients. This study investigated the course of antigen-induced arthritis in CCR9 deficient C57BL/6 mice in comparison to wild type animals to determine whether CCR9 is critical for disease severity and progression. Methods: Methylated bovine serum albumin was used for induction of uni-lateral arthritis by direct injection into the knee joints of preimmunized animals. Arthritis is confined to the injected joint allowing comparison with the normal opposing joint. Clinical severity of arthritis was assessed by measuring swelling in the arthritic joint in comparison to the normal joint. Histological analysis was performed to assess the extent of leukocyte infiltration and cartilage depletion. Results: Levels of swelling were not significantly different between wild type and CCR9 deficient mice. Similarly there was no significant difference in histological severity of arthritis when comparing CCR9-deficient mice to wild type mice. Conclusions: CCR9 was not required for development of synovial inflammation and cartilage destruction in the anti-gen-induced model of arthritis in C57BL/6 mice in this study. This may reflect a true lack of a pathogenic role of CCR9 on monocyte/macrophage function in vivo or it may reflect differences in the current antigen-induced arthritis model when compared to human RA.

Suppression of Methotrexate-Induced Elevations in the Serum Alanine Aminotransferase Level of Patients with Rheumatoid Arthritis Who Had Prior Hepatitis B Infection

Background: Hepatitis after the reactivation of hepatitis B virus (HBV) has been recognized serious in the patients with rheumatoid arthritis (RA) treated with biologics. Objectives: The objective of the present study was to search some common background which might be relevant to the host factors that provoke such a serious hepatitis. Methods: We retrospectively collected and analyzed all data of serum alanine aminotransferase (ALT) levels in selected patients with RA at random. Results: A significant association (P P P = 0.73) in the anti-HBcAb-positive RA group. In addition, the anti-HBcAb-positive RA patients showed significantly lower mean serum level of ALT (P P Conclusions: The anti-HBcAb-positive RA group showed the suppression of MTX-induced elevations in serum ALT level. However, this suppression was not found in patients experienced in the treatment with biologics, although it was preserved in those who had not experienced biologics. Failure of this suppressive mechanism of ALT in anti-HBcAb-positive RA patients treated with biologics could be possibly associated with serious hepatitis after the reactivation of HBV infection.

Treatment of a mouse model of collagen antibody-induced arthritis with human adipose-derived secretions

The use of adipose-derived cells as a treatment for a variety of diseases is becoming increasingly common. These therapies include the use of cultured mesenchymal stem cells (MSCs) and freshly isolated stromal vascular fraction (SVF) alone, or in conjunction with other cells such as adipocytes. There is a substantial amount of literature published on the therapeutic properties of MSCs and their secretions as the main driver of their therapeutic effect. However, there is little data available on the therapeutic potential of secretions from SVF, either with or without adipocytes. We investigated the ability of secretions from human adipose SVF alone and the SVF co-cultured with adipocytes as a proxy for cell therapy, to ameliorate an inflammatory disorder. This ethics approved study involved the treatment of collagen antibody-induced arthritis (CAIA) in mice with secretions from SVF, SVF co-cultured with adipocytes, or a vehicle control via both intravenous (IV) and intramuscular (IM) routes. Treatment outcome was assessed by paw volume, ankle size and clinical arthritis score measurements. Serum samples were obtained following euthanasia and analysed for a panel of 32 mouse cytokines and growth factors. The dose and timing regime used for the IM administration of both human secretion mixtures did not significantly ameliorate arthritis in this model. The IV administration of SVF adipocyte co-culture secretions reduced the paw volume, and significantly reduced the ankle size and clinical arthritis score when compared to the IV vehicle control mice. This was a superior therapeutic effect than treatment with SVF secretions. Furthermore, treatment with SVF adipocyte coculture secretions resulted in a significant reduction in serum levels of key cytokines, IL-2 and VEGF, involved in the pathogenesis of rheumatoid arthritis. Therefore, the SVF cocultured with adipocytes is an attractive therapeutic for inflammatory conditions.

Effect of Cornus officinalis glycoside on adjuvant-induced arthritis in rats

The aim of this study was to explore the effect of Cornus officinalis glucosides (COG) on adjuvant-induced arthritis in rats and its mechanism. Seventy-two rats were divided into six groups of normal, model, Dexasone (0.125 mg/kg), high-dose COG (240 mg/kg), mid-dose COG (120 mg/kg), and low-dose COG (60 mg/kg). Rat arthritis was induced by injection of Freund's complete adjuvant in the hind paws. All treatment started from the day the arthritis was induced. The edema degree of the adjuvant injection location was determined on days 1, 3, 5, 7, 9, 11, 13, 15, 17, 20, 23 and the opposite side was observed on days 11, 13, 15, 17, 20, 23 after the injection of adjuvant. All rats were sacrificed on day 24 after the injection of adjuvant for microscopic examination of the ankle, and for the study of the immunological molecular mechanism. The results showed that the COG significantly suppressed both the primary and secondary edema, improved pathological injuries of adjuvant arthritis (AA) rat ankles, significantly suppressed the proliferation of T lymphocytes and DTH reaction. It significantly suppressed IL-1, IL-6 and TNF-αproduction from peritoneal macrophages and PGE2 in plasma. In conclusion, the Cornus officinalis glucosides (COG) is able to prevent and cure the rat adjuvant-induced arthritis, and can suppress the production of pro-inflammatory cytokine IL-1, IL-6, TNF-αand PGE2.

Pharmacologic inducers of the uric acid exporter ABCG2 as potential drugs for treatment of gouty arthritis

Uric acid is the end product of purine catabolism and its plasma levels are maintained below its maximum solubility in water(6–7 mg/dl).The plasma levels are tightly regulated as the balance between the rate of production and the rate of excretion,the latter occurring in urine(kidney),bile(liver)and feces(intestinal tract).Reabsorption in kidney is also an important component of this process.Both excretion and reabsorption are mediated by specific transporters.Disruption of the balance between production and excretion leads to hyperuricemia,which increases the risk of uric acid crystallization as monosodium urate with subsequent deposition of the crystals in joints causing gouty arthritis.Loss-of-function mutations in the transporters that mediate uric acid excretion are associated with gout.The ATP-Binding Cassette exporter ABCG2 is important in uric acid excretion at all three sites:kidney(urine),liver(bile),and intestine(feces).Mutations in this transporter cause gout and these mutations occur at significant prevalence in general population.However,mutations that are most prevalent result only in partial loss of transport function.Therefore,if the expression of these partially defective transporters could be induced,the increased number of the transporter molecules would compensate for the mutation-associated decrease in transport function and hence increase uric acid excretion.As such,pharmacologic agents with ability to induce the expression of ABCG2 represent potentially a novel class of drugs for treatment of gouty arthritis.

Effect of Yangqixue Qufengshi Recipe (养气血祛风湿方) on Rheumatoid Arthritis Model Mice under Different Genetic Backgrounds

Objective： To study the effect of Yangqixue Qufengshi Recipe （养气血祛风湿方, YQXQFS） on rheumatoid arthritis （RA） model mice under different genetic backgrounds. Methods： Collagen Induced Arthritis （CIA） were established on HLA-DR4 transgenic （TG） mice and non-transgenic （NTG） mice, which partly were raised with YQXQFS, and the onset day of CIA, the level of type Ⅱ collagen （C Ⅱ ）-reactive antibodies and the pathological scores of CIA were assessed. Results： Under HLA-DR4 TG background （compared with NTG mice）, the earlier onset day of CIA （ 11.22±3.35 days vs 16.56 ±4.75 days, P〈0.05） and higher level of C Ⅱ-reactive antibodies （0. 2274±0. 1390μg/ml vs 0.1101±0. 0560μg/ml, P〈0.05） were observed, but the pathological scores of CIA remained unchange. YQXQFS could not influence the onset day of CIA and the level of C Ⅱ-reactive antibodies, but had a certain effect on the total pathological scores （6.56±3.43 scores vs 11.11±5.64 scores） and bone erosion （0.22±0.44 scores vs 1.67±1.50 scores） of CIA on NTG mice （P〈0.05）, NTG YQXQFS group compared with NTG experimental group. Conclusion： YQXQFS had a certain effect on RA model, but had no significant effect on HLA-DR4 related CIA.

The pain-related behavior changes correlate with the bone damage in a rat model of rheumatoid arthritis

Objective: In view of the extensive bone damage in rheumatoid arthritis, we used a commonly utilized animal model to detect behavioral changes in pain-related and the bone damage during the early disease, and to explore the correlation between bone damage and pain-related behavioral changes. Methods: Arthritis were induced in Sprague-Dawley (SD) male rats by injecting complete Freund's adjuvant (CFA) into the tails. Pain-related behavior changes were studied using the Hargreaves, VonFrey, and acetone tests on the 0, 7, 14, day and 28 day after CFA injection. The rats were sacrificed according the same schedule. The bone damage of the right proximal tibia was studied by microCT scan and bone histological slices. Results: Animals developed soft tissue inflammation and polyarthritis on 7 days after CFA injection, and arthritic score proved obvious arthritis were established within the study period. Mechanical hyperalgesia and cold allodynia were present in the affected hind paw from the 7 day through the 28 day, but the heat hyperalgesia and the mechanical allodynia lasted a short time after CFA injection. Trabecular bone number (Tb.N), Tissue Mineral Content (TMC) and Bone Volume to Tissue Volume (BV/TV) in the proximal tibia by microCT scan were also reduced after induction, especial 14 days after CFA injection. The bone histological slices showed the trabecular bone and proteoglycan diminished, the bone damage severity scores became more severely on the 7 day after CFA injection. Using analysis of covariance, these changes had statistical significance compared with baseline. By linear regression analysis demonstrated mechanical hyperalgesia and cold allodynia correlated well with arthritic score, bone damage parameters and bone damage severity scores. Conclusion: Adjuvant-induced arthritis (AA) were observed after CFA injection and lasted within the later experimental period. Pain-related behavioral changes were observed in the early time of AA. Bone damage was also occurred with arthritis development. Pain-related behavioral change correlated well with arthritic score and bone damage parameters.

Human umbilical cord mesenchymal stem cells as treatment of adjuvant rheumatoid arthritis in a rat model

AIM:To investigate the effect of human umbilical cord stem cells,both mesenchymal and hematopoietic(CD34+),in the treatment of arthritis.METHODS:Mesenchymal stem cells(MSCs) and hematopoietic(CD34+) stem cells(HSC) were isolated from human umbilical cord blood obtained from the umbilical cord of healthy pregnant donors undergoing fullterm normal vaginal delivery.MSC,HSC,methotrexate(MTX) and sterile saline were injected intra-articularly into the rat hindpaw with complete freunds adjuvant(CFA) induced arthritis after the onset of disease(day 34),when arthritis had become well established(arthritis score ≥ 2).Arthritic indices were evaluated and the levels of interleukin(IL)-1,tumor necrosis factor(TNF)-α and interferon(IFN)-γ and anti-inflammatory cytokine IL-10 in serum were determined using enzyme-linked immunosorbent assay.Animals of all groups were sacrificed 34 d after beginning treatment,except positive control(PC) which was sacrificed at 10,21 and 34 d for microscopic observation of disease progression.We used hematoxylin,eosin and Masson's trichrome stains for histopathological examination of cartilage and synovium.RESULTS:The mean arthritis scores were similar in all groups at 12 and 34 d post immunization,with no statistical significant difference.Upon the injection of stem cells(hematopoietic and mesenchymal),the overall arthritis signs were significantly improved around 21 d after receiving the injection and totally disappeared at day 34 post treatment in MSC group.Mean hindpaw diameter(mm) in the MSC rats was about half that of the PC and MTX groups(P = 0.007 and P = 0.021,respectively) and 0.6 mm less than the HSC group(P = 0.047),as indicated by paw swelling.Associated with these findings,serum levels of TNF-α,IFN-γ and IL-1 decreased significantly in HSC and MSC groups compared to PC and MTX groups(P < 0.05),while the expression of IL-10 was increased.Histopathological examination with H and E stain revealed that the MTX treated group showed significant reduction of leucocytic infiltrate and hypertrophy of the synovial tissue with moderate obliteration of the joint cavity.Stem cells treated groups(both hematopoietic CD34+ and mesenchymal),showed significant reduction in leucocytic infiltrate and hypertrophy of the synovial tissue with mild obliteration of the joint cavity.With Masson's trichrome,stain sections from the PC group showed evidence of vascular edema of almost all vessels within the synovium in nearly all arthritic rats.Vacuoles were also visible in the outer vessel wall.The vessel became hemorrhagic and finally necrotic.In addition,there was extensive fibrosis completely obliterating the joint cavity.The mean color area percentage of collagen in this group was 0.324 ± 0.096,which was significantly increased when compared to the negative control group.The mean color area percentage of collagen in hematopoietic CD34+ and mesenchymal groups was 0.176 ± 0.0137 and 0.174 ± 0.0197 respectively,which showed a marked decrement compared to the PC group,denoting a mild increase in synovial tissue collagen fibers.CONCLUSION:MSC enhance the efficacy of CFAinduced arthritis treatment,most likely through the modulation of the expression of cytokines and amelioration of pathological changes in joints.

Anti-arthritis effect of berberine associated with regulating energy metabolism of macrophage through AMPK/HIF-1α pathway

OBJECTIVE To investigate berberine(BBR)attenuates arthritis in adjuvant-induced arthritic(AA)rats associated with regulating the energy metabolism and correcting the polarization of macrophages through activation of AMP-activated protein kinase(AMPK)and inhibition of hypoxia inducible factor 1α(HIF-1α).METHODS AA rats were treated with BBR(40,80,or 160 mg·kg-1)from days 15 to 29 after immunization.The histopathology of ankle joint was examined through hematoxylin-eosin(HE)staining.The concentrations of tumour necrosis factor-α(TNF-α),interleukin-6(IL-6),IL-1β,IL-2,IL-17A,interferon-gamma(IFN-γ),monocyte chemotactic protein 1(MCP-1),IL-4,IL-10,transforming growth factor-β1(TGF-β1),ATP,and lactic acid were measured by using ELISA kits.The percentage of M1 and M2 macro⁃phage cells in joint tissues were evaluated by immune-fluorescence.The expressions of p-AMPK and HIF-1αin joint of AA rats were determined according to immunohistochemistry analysis.The migration of macrophage was detected by Transwell assays.The expression of inducible nitric oxide synthase(iNOS),Arginase-1(Arg1),p-AMPK,AMPK and HIF-1αwere examined by Western blotting.The labeled macrophages were observed with laser confocal microscopy.RESULTS BBR relieved signs and symptoms of AA rats and reversed pathological changes.BBR treatment group exhibited decreases in pro-inflammatory cytokines(TNF-α,IL-1β,IL-6,IL-2,IL-17A,IFN-γ,and MCP-1)coupled with increases anti-inflammatory cytokines(IL-4,IL-10,TGF-β1)in the serum.The number of M1 macrophage was reduced,while the number of M2 macrophage was increased in BBR group joint tissues.Moreover,BBR showed marked up-regu⁃lation the expression of p-AMPK and down-regulation the expression of HIF-1αin joint of AA rats.Next in vitro study,we found BBR up-regulated the expression of p-AMPK,Arg1(M2 marker)and down-regulated the expression of HIF-1α,iNOS(M1 marker)induced by LPS in peritoneal macrophages from normal SD rat.Furthermore,BBR treatment inhibited the migration of macrophages stimulated by LPS.The level of ATP was elevated and lactic acid was reduced in LPSinduced macrophages after treated by BBR.However,Compound C significantly attenuated the effects of BBR on acti⁃vated macrophages.CONCLUSION BBR alleviates inflammation by regulating energy metabolism and correcting the polarization of macrophage through AMPK-HIF-1αpathway.BBR might have great therapeutic value for RA.

Reactive Arthritis: From Clinical Features to Pathogenesis

Reactive arthritis (ReA) is a sterile synovitis which occurs after a gastrointestinal or urogenital infection. ReA belongs to Spondyloarthritis (SpA), a group of diseases that share several clinical and radiological features including familiar clustering, absence of rheumatoid factor and association with HLA-B27. Clinically, ReA is characterized by an asymmetric arthritis predominantly affecting the lower limbs, often associated with urethritis, conjunctivitis and other extraarticular symptoms. The ReA prevalence depends on the incidence of causative pathogens. The ReA diagnosis is based on clinical features and serological tests to evidence previous infection. Different treatment including antibiotics, disease modifying antirheumatic drugs (DMARs) and biologic agents has been recommended. Even though knowing that infections trigger the joint inflammation, the ReA pathogenesis remains to be poorly understood. Several animal models and in vitro studies have been used to elucidate the mechanisms involved in ReA development. In this sense, HLA-B27 transgenic rat or mice have been used to explain the role of this molecule in SpA aetiopathogenesis. Moreover, the infectious model of Yersinia-induced ReA in rodents has shed some lights on the relationship between host genetic susceptibility to infection and abnormal immune response in ReA development. Understanding the immune mediators triggering ReA will contribute to find a specific treatment for this arthritis. In this review, we focus on clinical features, epidemiology, treatment, and the different attempts to understand the pathogenesis of ReA.