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Background/Objectives: Rheumatoid arthritis (RA) is a systemic chronic autoimmune disease characterized by a protracted course, high rates of morbidity, and disability yet lacks effective therapeutic modalities. Levamisole (LVM), an immunomodulatory drug, has been clinically reported for its potential in RA treatment, while its therapeutic mechanism toward RA remains to be elucidated. Hence, this study provides theoretical support for the application of LVM in the treatment of RA. Methods: This study employed male Sprague–Dawley (SD) rats to construct the adjuvant-induced arthritis (AIA) model, administering LVM orally (5 mg/kg, 15 mg/kg, and 45 mg/kg) for 25 days. An evaluation of LVM's therapeutic effects on RA was conducted through arthritis index scores, paw pad thickness, paw volume, hematoxylin and eosin (H&E) staining, 3D microcomputed tomography (micro-CT) scans, serum levels of pro-/anti-inflammatory cytokines, and serum biochemical indicators. Western blotting and immunohistochemistry staining were utilized to measure the expression levels of phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) proteins in synovial and ankle joint tissues. Results: Treatment with the median dose of LVM (15 mg/kg, M-LVM) significantly reduced the arthritis index (p < 0.01), paw pad thickness (p < 0.001), and paw volume (p < 0.01) without affecting body weight. Additionally, M-LVM alleviated inflammatory lesions in the synovium and ankle joints and also normalized serum levels of interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and transforming growth factor-beta (TGF-β). The Model group exhibited significant increases in serum levels of alkaline phosphatase (ALP) (p < 0.01), creatine kinase (CK) (p < 0.05), and glucose (GLU) (p < 0.001) compared with the Control group; however, M-LVM effectively regulated these parameters to normal levels. Western blotting and immunohistochemistry staining revealed that PI3K-/Akt-related proteins were highly expressed in the synovial and ankle joint tissues of rats in the Model group, while treatment with M-LVM significantly reduced the expression of these proteins. Furthermore, histological examination of major organs (heart, liver, lungs, kidneys, and thymus) showed no significant pathological changes, with the exception of the spleen, where M-LVM ameliorated splenic lesions. Conclusions: We demonstrate that LVM at an optimal dose substantially relieves synovitis and bone erosion in AIA rats by inhibiting the PI3K/Akt signaling pathway. [ABSTRACT FROM AUTHOR]

Background and Purpose: White adipose tissue (WAT) is involved in rheumatoid arthritis (RA). This study explored its potential as an antirheumatic target. Experimental Approach: WAT status of healthy and adjuvant‐induced arthritis (AIA) rats were compared. The contribution of WAT to RA pathology was evaluated by pre‐adipocyte transplant experiments and by dissecting perirenal fat pads of AIA rats. The impact of RA on WAT was investigated by culturing pre‐adipocytes. Proteins differentially expressed in WAT of healthy and AIA rats were identified by the UPLC/MS2 method. These together with PPARγ siRNA and agonist were used to treat pre‐adipocytes in vitro. The medium was used for THP‐1 monocyte culture. Key Results: Compared with healthy controls, AIA WAT was smaller but secreted more leptin, eNAMPT, MCP‐1, TNF‐α, and IL‐6. AIA rat pre‐adipocytes increased the levels of these adipokines in healthy recipients. RA patients' serum induced a similar secretion change and impaired differentiation of pre‐adipocytes. Adipectomy eased AIA‐related immune abnormalities and arthritic manifestations. Hepatokines PON1, IGFBP4, and GPIHBP1 were among the differential proteins in high levels in RA blood, and induced inflammatory secretions by pre‐adipocytes. GPIHBP1 inhibited PPARγ expression and caused differentiation impairment and inflammatory secretion by pre‐adipocytes, a similar outcome to PPARγ‐silencing. This endowed the cells with an ability to activate monocytes, which can be abrogated by rosiglitazone. Conclusion and Implications: Certain hepatokines potentiate inflammatory secretions by pre‐adipocytes and expedite RA progression by inhibiting PPARγ. Targeting this signalling or abnormal WAT secretion by various approaches may reduce RA severity. [ABSTRACT FROM AUTHOR]

Objectives: We examined the antirheumatoid effects of piperlongumine (PLM) on rat adjuvant-induced arthritis (AIA) and explored the underlying mechanisms involved. Methods: PLM (2.5, 5, and 10 mg/kg) was administered intraperitoneally to AIA rats to assess its effectiveness. Blood, thymus, spleen, ankle joint, and synovial tissue samples were gathered for subsequent analyses, like enzyme-linked immunosorbent assay, thymus/spleen index measurement, ankle joint pathological examination, immunohistochemistry assay, polymerase chain reaction, and western blot assay. Moreover, the involvement of osteoprotegerin (OPG)/receptor activators of nuclear factor κB ligand (RANKL)/nuclear factor-κB (NF-κB) signaling was investigated. Key findings: PLM effectively relieved inflammation and joint destruction in AIA rats, as indicated by reductions in hind paw swelling, arthritis index, thymus/spleen index, ankle joint pathological damage, production of TNF-α, IL-1β, and IL-6 in both serum and synovium, and osteoclast formation. Also, PLM treatment raised OPG production, reduced RANKL expression, and elevated the OPG/RANKL ratio in synovial tissues. Furthermore, PLM prevented IκBα degradation and phosphorylation, resulting in a reduced expression of the nuclear NF-κB p65 protein in AIA rat synovial tissues. Conclusions: PLM demonstrated strong antiarthritic effects in rats with AIA by influencing the OPG/RANKL/NF-κB signaling pathway, highlighting its potential clinical relevance in treating rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

To examine early mitigation and conservative effects of low-dose gamma radiation (LDR) or spirulina (SPR) algae on inflammation, oxidative stress and liver function in experimentally-induced arthritis in rats, and comparing such effects to conventionally used rheumatoid arthritis (RA) drugs; methotrexate (MTX) and hydroxychloroquine (HCQ) in an attempt to unleash a safer remedy/therapeutic modality for RA management. Male Wister albino rats were rendered arthritic by sub-plantar injection of 0.1 ml Freund's complete adjuvant (FCA). Adjuvant-induced arthritis (AIA) rats were treated with each of LDR (0.5 Gy at day 0 of arthritis induction), MTX (1 mg/kg/week, intra-peritoneal), HCQ sulphate (15 mg/kg/day, orally), MTX + HCQ, and SPR (1 g/kg/day, orally) for 28 days. Sub-plantar injection of FCA led to marked increase in paw volume accompanied with increased serum level of C-reactive protein (CRP) and oxidative stress markers including malondialdehyde (MDA) and nitric oxide (NO) levels. Exposure to LDR did not induce any significant alteration in the estimated parameters. Treatment with MTX and HCQ alone or combined induced deterioration in liver function (transaminases), insignificantly reduced paw edema, yet failed to attenuate CRP, MDA and NO levels. Instead, treatment with SPR significantly guarded against changes in nearly all measured parameters and kept liver function at normal level. This is a leading work showing the hepato-preservative impact of spirulina as a promising alternative therapy during the course management of RA. It could thus be considered as a potential option in the management armamentarium of RA. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a systemic autoimmune disease dominated by chronic inflammatory lesions of peripheral synovial joints. Growing evidence suggests that abnormal lipid metabolism levels contribute to the progression of RA. Although several metabolomics studies have shown abnormality in the RA lipidome, the relationship between the overall lipid metabolites and RA has not been systematically evaluated. In this study, an untargeted lipidomics method based on ultra performance liquid chromatography‐mass spectrometry (UPLC–MS) was used to analyze the serum and urine lipidomes of adjuvant‐induced arthritis rats to study the characteristics of lipid metabolism changes in the rats and search lipid markers for diagnosing RA. By combining with orthogonal partial least squares discriminant analysis, a total of 52 potential lipid markers were identified, mainly involved in sphingolipid metabolism, glycerophospholipid metabolism, sterol lipid metabolism, glycerolipid metabolism and fatty acid metabolism, which provided crucial insight into lipid metabolism disturbances in RA. Further receiver operating characteristic analysis revealed that the areas under the curve of PC(22:4/16:0), PI(18:1/16:0) and LacCer(d18:1/12:0) from serum and 25‐hydroxycholesterol from urine were 0.94, 1.00, 1.00 and 1.00, respectively, indicating the high predictive ability of this method for RA. In this study, our results indicated that a combination of serum and urine analysis can provide a more comprehensive and reliable assessment of RA, and a UPLC–MS‐based lipidomics strategy is a powerful tool to search for potential lipid markers associated with RA and explore the pathogenesis of RA. [ABSTRACT FROM AUTHOR]

Leflunomide is an isoxazole immunomodulating drug used to treat rheumatoid arthritis (RA). It is adopted as a metal-containing molecule to proceed with saturated salts of essential and detected metals; it amends the pharmacokinetic and pharmacodynamics activity of leflunomide to provide [M(Lef)4]X2-type complexes. Earlier it has been reported that after forming complexes with metals, leflunomide anti-arthritic activity was significantly altered in an acute arthritic model. In the present study, we evaluated the possible modification in anti-arthritic activities of leflunomide–metal complexes (Mg+2, Ca+2, Fe+2, Zn+2) with and without an anti-depressant drug, i.e., fluoxetine (10 mg/kg) in a chronic AIA model. Rats (n = 5) were administered with 0.1 mL of CFA into the right hind paw while treated groups received leflunomide and its metal complexes orally (3.2 mg/kg) for 24 days. On the final day of experiment, rats were sacrificed; a specific rat immunoassay ELISA kit was used to assess TNF-α in serum samples and read at 450 nm; a tissue sample of a paw was homogenized in a phosphate buffer using DCFH-DA dye for binding to assess ROS. A rat's brain sample was homogenized and evaluated for tryptophan, serotonin (5-HT), and HIAA by RP-HPLC with EC detector. The overall TNF production was altered in treated rats. In addition, a decreased ROS was observed in all categories, except lef+Mg+2 group. Moreover, depletion in the brain indolamine levels were found in treated groups; an upraised level of these indolamines was observed when fluoxetine was added. It is concluded that metals affect leflunomide activity on complexation and simultaneous administration of fluoxetine cope up with the depression in arthritic-induced rats. [ABSTRACT FROM AUTHOR]

Background: Valproic acid (VA) is a compound used for many neurological disorders, which is also known as a histone deacetylase inhibitor. The impacts of VA on adjuvant-induced arthritis (AIA) in rats were investigated. Objectives: To investigate the possible osteoprotective and anti-inflammatory effects of VA in rheumatoid arthritis (RA). Materials and Methods: AIA was achieved through subdermal injection of complete Freund’s adjuvant (CFA) into the rat hindpaw. Forty Swiss albino rats were recruited in this study. These rats were divided into four groups: the normal control group received 0.1 mL phosphate buffer saline intraperitoneally each day, the positive control group received 0.75 mg/kg intraperitoneal once weekly dose of methotrexate, the AIA group received CFA without treatment, and the VA group received 300 mg/kg/day intraperitoneal dose of VA. Statistical analysis was done, and a P value of less than 0.05 was considered as statistically significant. Results: VA (300 mg/kg body weight) administered intraperitoneally could significantly reverse the effect of adjuvant arthritis on bone mineral density and bone mineral content in addition to an improvement in bone formation markers (osteoprotegerin, osteoprotegerin/RANKL ratio). Serum levels of tumor necrosis factor and interleukin 1b were significantly reduced by VA treatment. Reduced serum malondialdehyde with the elevated superoxide dismutase level was also achieved. Conclusion: These findings support the evidence that VA has a positive effect on bone anabolism and its anti-inflammatory properties could be considered as a bonus in inflammatory disorders induced bone loss such as RA.

New effective wound healing agents are a priority for modern clinical pharmacology. A promising approach would be to develop medicinal products that promote angiogenesis, which is a critical step in wound healing. The aim of the study was to evaluate the wound healing effect of a medicinal product based on recombinant human angiogenin in gel form in various experimental models. Materials and methods: white outbred male rats were used as experimental ani mals. The study compared healing effects of a regenerating product containing recombinant human angiogenin (0.0025%) in gel form and a reference product in full-thickness excision, incision, and burn wound models. The healing effect of the test product in treating chronic wounds was assessed in a model of alloxan-induced diabetes mellitus. The anti-inflammatory effect of the test product containing recombinant human angiogenin was compared with that of another reference product in a model of adjuvant-induced arthritis. Results: according to the study, the test product based on recombinant human angiogenin exerts higher wound healing effect in treating excision, incision, and burn wounds than the reference product (Solcoseryl gel). Being applied, the test product intensifies tissue repair in chronic wounds in the model of alloxan-induced diabetes. The dissociation of necrotic tissues and the progression towards epithelialisation at wound edges are more rapid. The anti-inflammatory effect of the test product based on recombinant human angiogenin is comparable with that of the reference product (Diclofenac gel). Conclusions: the test product based on recombinant human angiogenin in gel form was found to have pronounced wound healing and anti-inflammatory effects comparable with those of reference products.

This study characterizes rheumatoid arthritis‐related free fatty acids (FFAs) changes using adjuvant‐induced arthritis (AIA) model. Blood FFAs of healthy and AIA rats are periodically determined. During acute inflammation, FFAs levels are analyzed under both fasting and non‐fasting conditions. Oral intake capacities are compared by everted intestinal sac experiment. Tissue distribution of FFAs in the rats fed with/without linolenic acid is also investigated. AIA decreases FFAs in rats. Saturated FFAs are gradually recovered, but unsaturated FFAs are further reduced till the secondary inflammation. FFAs level gap remains unchanged regardless of feeding/fasting, and intestinal intake capacities of the rats are similar. FFAs levels in liver fluctuate in accordance with blood levels. Increased carnitine palmitoyltransferase 1 (CPT‐1) reveals the accelerated FFAs utilization in AIA rats, resulting in the accumulation of acetoacetic acid and 2‐hydroxybutyrate. Hepatocytes incubated with AIA serum take in more FFAs than normal controls when supply is sufficient. To the opposite, intracellular FFAs are reduced after AIA serum stimulus without additional supply. Besides, AIA serum‐challenged cells produce more CPT‐1. Hence, the reduced circulating FFAs in AIA rats should be attributed to the accelerated utilization in liver. Practical Applications: This study provides additional possible therapeutic approaches for the treatment of RA by focusing on the changes of blood FFAs. Obtained clues demonstrate that liver will be a key in the elucidation of RA‐related lipid paradox, and diet supplement of the unsaturated FFAs will be beneficial in treating RA. [ABSTRACT FROM AUTHOR]

Objectives: Acupuncture has been found to be effective at relieving many inflammatory pain conditions, including rheumatoid arthritis (RA). We aimed to assess the anti-inflammatory potential of manual acupuncture (MA) treatment of RA using adjuvant-induced arthritic (AIA) rats and to explore the underlying mechanisms. Methods: The anti-inflammatory and analgesic actions of MA at ST36 (Zusanli) in AIA rats were assessed using paw withdrawal latency and swelling, histological examination and cytokine detection by enzyme-linked immunoassay (ELISA). The cell–cell communication (CCC) network was analyzed with a multiplex immunoassay of 24 immune factors expressed in the inflamed joints, and the macrophage and Treg populations and associated cytokines regulated by MA were investigated using reverse-transcription quantitative polymerase chain reaction (RT-qPCR), ELISA and flow cytometry. Results: MA markedly decreased heat hyperalgesia and paw swelling in AIA rats. MA-treated rats also exhibited decreased levels of pro-inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-1β) coupled with increased anti-inflammatory cytokines (IL-10, transforming growth factor (TGF)-β1) in the ankle joints at protein and mRNA levels. CCC network analysis confirmed that macrophages are of critical importance and are potential therapeutic targets in RA. Repeated treatment with MA triggered a macrophage phenotypic switch in the paws, with fewer M1 macrophages. Prominent increases in the Treg cell population and TGF-β1 in the popliteal lymph nodes demonstrated the immunomodulatory effects of MA. Furthermore, a selective TGF-β1-receptor inhibitor, SB431542, attenuated the anti-inflammatory effects of MA and MA-induced suppression of the levels of M1-released cytokines. Conclusion: These findings provide novel evidence that the anti-inflammatory and analgesic effects of MA on RA act through phenotypic modulation involving the inhibition of M1 macrophage polarization and an increase in the Treg cell population, highlighting the potential therapeutic advantages of acupuncture in controlling pain and ameliorating inflammatory conditions. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to explore the mechanism by which long non-coding ribonucleic acids (lncRNA) X-inactive specific transcript (XIST) affects the progression of adjuvant-induced arthritis (AIA). Materials and methods: Freund's complete adjuvant was used to induce arthritis in rats. The polyarthritis, spleen and thymus indexes were calculated to evaluate AIA. Hematoxylin-eosin (H&E) staining was used to reveal the pathological changes in the synovium of AIA rats. Enzyme-linked immunosorbent assay (ELISA) was performed to detect the expression of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6 and IL-8 in the synovial fluid of AIA rats. The cell continuing kit (CCK)-8, flow cytometry, and Transwell assays were used to assess the proliferation, apoptosis, migration and invasion of transfected fibroblast-like synoviocytes (FLS) isolated from AIA rats (AIA-FLS). Dual-luciferase reporter assay was performed to verify the binding sites between XIST and miR-34b-5p or between YY1 mRNA and miR-34b-5p. Results: The XIST and YY1 were highly expressed, and miR-34a-5p was lowly expressed in the synovium of AIA rats and in AIA-FLS. Silencing of XIST impaired the function of AIA-FLS in vitro and inhibited the progression of AIA in vivo. The XIST promoted the expression of YY1 by competitively binding to miR-34a-5p. Inhibition of miR-34a-5p strengthened the function of AIA-FLS by upregulating XIST and YY1. Conclusion: The XIST controls the function of AIA-FLS and may promote the progression of rheumatoid arthritis via the miR-34a-5p/YY1 axis. [ABSTRACT FROM AUTHOR]

This study evaluated the protective effect of different dietary ω-6/ω-3 ratios in oils obtained from various nuts (walnut, peanut, cashew, and hazelnut) against morphological features and markers of inflammation on an adjuvant-induced arthritis rat model. Rheumatoid arthritis (RA) was induced via intradermal injection of heat-killed Mycobacterium tuberculosis. Five groups of rats with RA (n = 5) were randomly categorized as follows: control positive, walnut oil group, peanut oil group, cashew nut oil group, and hazelnut oil group. Another five healthy rats served as a normal non-arthritic (control) group. We assessed the therapeutic effects by measuring arthritis scores during the experiment and serum inflammatory markers at the end of the study. The serum levels of the rheumatoid factor, TNF-α, IL-6, IL-1β, and PGE2, were significantly (p ≤ 0.05) reduced in all treatment groups. The daily consumption of nut oils ameliorates clinical and morphological abnormalities by inhibiting the inflammatory cells that produce inflammatory interleukins and eicosanoids. [ABSTRACT FROM AUTHOR]

Background and aim: The present study investigated the effects of orally administered α-tocopherol-loaded polycaprolactone nanoparticles on the articular inflammation and systemic oxidative status of middle-aged Holtzman rats with Freund's adjuvant-induced polyarthritis, a model for rheumatoid arthritis. Intraperitoneally administered free α-tocopherol provided the reference for comparison. Experimental procedure: Two protocols of treatment were followed: intraperitoneal administration of free α-tocopherol (100 mg/kg i.p.) or oral administration of free and nanoencapsulated α-tocopherol (100 mg/kg p.o.). Animals were treated during 18 days after arthritis induction. Results: Free (i.p.) and encapsulated α-tocopherol decreased the hind paws edema, the leukocytes infiltration into femorotibial joints and the mRNA expression of pro-inflammatory cytokines in the tibial anterior muscle of arthritic rats, but the encapsulated compound was more effective. Free (i.p.) and encapsulated α-tocopherol decreased the high levels of reactive oxygen species in the brain and liver, but only the encapsulated compound decreased the levels of protein carbonyl groups in these organs. Both free (i.p.) and encapsulated α-tocopherol increased the α-tocopherol levels and the ratio of reduced to oxidized glutathione in these organs. Conclusion: Both intraperitoneally administered free α-tocopherol and orally administered encapsulated α-tocopherol effectively improved inflammation and systemic oxidative stress in middle-aged arthritic rats. However, the encapsulated form should be preferred because the oral administration route does not be linked to the evident discomfort that is caused in general by injectable medicaments. Consequently, α-tocopherol-loaded polycaprolactone nanoparticles may be a promising adjuvant to the most current approaches aiming at rheumatoid arthritis therapy.

A series of (4-(1,2,4-oxadiazol-5-yl) phenyl)-2-aminoacetamide derivatives showed good anti-neuroinflammation in our previous study. Some studies have proven that the anti-inflammatory compounds effective for some specific diseases could also be used to treat other inflammatory diseases. In this study, the effects of these compounds on arthritis were further analyzed. First, in-vitro anti-inflammatory activity assessment indicated that these compounds have good anti-inflammatory activity. Among them, compound f15 showed the most prominent performance, it could significantly inhibit the production of relevant inflammatory factors in lipopolysaccharide (LPS)-induced RAW264.7 cells, with IC50 values of 1.55 ± 0.33, 3.83 ± 0.19, and 7.03 ± 0.24 μM against NO, IL-1β, and TNF-α production, respectively. Preliminary mechanism studies indicated that f15 blocked the excitation of nuclear factor κB (NF-кB) signaling pathway in a concentration-dependent manner. Furthermore, in-vivo experiment showed that f15 reduced secondary foot swelling and arthritic index in adjuvant-induced arthritis (AIA) rats and inhibited the production of TNF-α and IL-1β in serum. Histopathological analysis revealed that f15 alleviated inflammatory cell infiltration and synovial hyperplasia in rats with AIA. Thus, compound f15 could be considered to have the potential to be developed as a treatment for arthritis. [ABSTRACT FROM AUTHOR]

Anabasis articulata (AA) is commonly found in the Iraqi desert and is utilized in traditional medicine to cure kidney infections, eczema, fever, and diabetes. The paper aimed to identify the anti-arthritic impact of AA on arthritis models in rats. Complete Freund's Adjuvant (CFA) was used intradermally (ID) for the induction of arthritis. The author classified animals into four groups randomly: The first group took normal saline (control), the second group received AA orally for 14 days before induction and continue 17 days after induction, the third group was induced by CFA and received normal saline orally (model group), and the fourth group took AA orally 17 days after induction. AA administration increased body weight (BW) but decreased arthritis index (AI), histopathological scores, and vascular endothelial growth factor expression in synovial cells. AA has an important antiangiogenesis and anti-arthritic activity in arthritis model rats.

Leflunomide is an isoxazole immunomodulating drug used to treat rheumatoid arthritis (RA). It is adopted as a metal-containing molecule to proceed with saturated salts of essential and detected metals; it amends the pharmacokinetic and pharmacodynamics activity of leflunomide to provide [M(Lef)4]X2-type complexes. Earlier it has been reported that after forming complexes with metals, leflunomide anti-arthritic activity was significantly altered in an acute arthritic model. In the present study, we evaluated the possible modification in anti-arthritic activities of leflunomide–metal complexes (Mg+2, Ca+2, Fe+2, Zn+2) with and without an anti-depressant drug, i.e., fluoxetine (10 mg/kg) in a chronic AIA model. Rats (n = 5) were administered with 0.1 mL of CFA into the right hind paw while treated groups received leflunomide and its metal complexes orally (3.2 mg/kg) for 24 days. On the final day of experiment, rats were sacrificed; a specific rat immunoassay ELISA kit was used to assess TNF-α in serum samples and read at 450 nm; a tissue sample of a paw was homogenized in a phosphate buffer using DCFH-DA dye for binding to assess ROS. A rat’s brain sample was homogenized and evaluated for tryptophan, serotonin (5-HT), and HIAA by RP-HPLC with EC detector. The overall TNF production was altered in treated rats. In addition, a decreased ROS was observed in all categories, except lef+Mg+2 group. Moreover, depletion in the brain indolamine levels were found in treated groups; an upraised level of these indolamines was observed when fluoxetine was added. It is concluded that metals affect leflunomide activity on complexation and simultaneous administration of fluoxetine cope up with the depression in arthritic-induced rats.

Anabasis articulata (AA) is commonly found in the Iraqi desert and is utilized in traditional medicine to cure kidney infections, eczema, fever, and diabetes. The paper aimed to identify the anti-arthritic impact of AA on arthritis models in rats. Complete Freund's Adjuvant (CFA) was used intradermally (ID) for the induction of arthritis. The author classified animals into four groups randomly: The first group took normal saline (control), the second group received AA orally for 14 days before induction and continue 17 days after induction, the third group was induced by CFA and received normal saline orally (model group), and the fourth group took AA orally 17 days after induction. AA administration increased body weight (BW) but decreased arthritis index (AI), histopathological scores, and vascular endothelial growth factor expression in synovial cells. AA has an important antiangiogenesis and anti-arthritic activity in arthritis model rats. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is characterized by systemic inflammation and synovial hyperplasia. Pristimerin, a natural triterpenoid isolated from plants belonging to the Celastraceae and Hippocrateaceae families, has been reported to exhibit anti-inflammation and anti-proliferation activities. Our study aims to reveal the antiarthritic effects of pristimerin and explore its potential mechanism using in vitro, in silico, and in vivo methods. In the present study, pristimerin treatment led to a dose-dependent decrease in cell viability and migration in TNF-α stimulated human rheumatoid arthritis fibroblast-like synoviocytes MH7A. Moreover, UPLC-LTQ-Orbitrap-based cell metabolomics analysis demonstrated that phospholipid biosynthesis, fatty acid biosynthesis, glutathione metabolism and amino acid metabolic pathways were involved in TNF-α induced MH7A cells after pristimerin treatment. In addition, the adjuvant–induced arthritis (AIA) rat model was employed, and the results exhibited that pristimerin could effectively relieve arthritis symptoms and histopathological damage as well as reduce serum levels of TNF-α, NO and synovial expressions of p-Akt and p-Erk in AIA rats. Furthermore, network pharmacology analysis was performed to visualize crucial protein targets of pristimerin for RA treatment, which showed that the effects were mediated through the MAPK/Erk1/2, PI3K/Akt pathways and directing binding with TNF-α. Taken together, our study not only offered new insights into the biochemical mechanism of natural compounds for RA treatment, but also provided a strategy that integrated in vitro, in silico and in vivo studies to facilitate screening of new anti-RA drugs. [ABSTRACT FROM AUTHOR]

The class III histone deacetylase sirtuin 1 (SIRT1) plays a pivotal role in numerous biological and physiological functions, including inflammation. An association between SIRT1 and proinflammatory cytokines might exist. In addition to their important role in inflammation associated with rheumatoid arthritis (RA), proinflammatory cytokines mediate the development of systemic effects. Here, we evaluated systemic SIRT1 expression and enzymatic activity, in peripheral blood mononuclear cells (PBMCs) and in liver isolated from rats with adjuvant-induced arthritis (AIA), treated or not with low or high doses of glucocorticoids (GCs). We also measured the production of tumour necrosis factor alpha (TNF) and interleukin-1 beta (IL-1 beta) in PBMCs and liver. We found that SIRT1 expression and activity increased in PBMCs of AIA rats compared to healthy controls and decreased under GC treatment. Similarly, we observed an increased SIRT1 activity in the liver of AIA rats compared to healthy controls which decreased under high doses of GCs. We also found an increase in IL-1 beta and TNF levels in the liver of AIA rats compared to healthy controls, which decreased under high doses of GC. We did not observe a significant correlation between SIRT1 activity and proinflammatory cytokine production in PBMC or liver. In contrast, a strong positive correlation was found between the liver levels of TNF and IL-1 beta (rho=0.9503, p=7.5x10−21). Our results indicate that increased inflammation in AIA rats compared to healthy control is accompanied by an increased SIRT1 activity in both PBMCs and liver, which could be decreased under GC treatment.

Elastin peptides display a wide range of biological activities. This study aimed to investigate the ameliorative effect of tuna elastin peptides on adjuvant-induced arthritis (AIA). The daily administration of tuna elastin peptides markedly downregulated the levels of proinflammatory cytokines and upregulated the immunosuppressive cytokines in the serum, bone, and colon of the AIA model. 16S rRNA sequencing showed that tuna elastin peptide-treated mice exhibited reversed gut microbiota dysbiosis and increased abundance of Lactobacillus and Clostridium. Additionally, metabolomics indicated that short-chain fatty acid (SCFAs) production was increased in tuna elastin peptide-treated mice. The ameliorating arthritis effects of tuna elastin peptides were transmitted by transplanting the fecal microbiota from mice treated with high levels of elastin peptides. These results indicate the potential of tuna elastin peptides as beneficial functional food that ameliorates rheumatoid arthritis.

Purpose S-propargyl-cysteine (SPRC), an excellent endogenous hydrogen sulfide (H2S) donor, could elevate H2S levels via the cystathionine γ-lyase (CSE)/H2S pathway both in vitro and in vivo. However, the immediate release of H2S in vivo and daily administration of SPRC potentially limited its clinical use. Methods To solve the fore-mentioned problem, in this study, the dendritic mesoporous silica nanoparticles (DMSN) was firstly prepared, and a sustained H2S delivery system consisted of SPRC and DMSN (SPRC@DMSN) was then constructed. Their release profiles, both in vitro and in vivo, were investigated, and their therapeutical effect toward adjuvant-induced arthritis (AIA) rats was also studied. Results The spherical morphology of DMSN could be observed under scanning Electron Microscope (SEM), and the transmission electron microscope (TEM) images showed a central-radiational pore channel structure of DMSN. DMSN showed excellent SPRC loading capacity and attaining a sustained releasing ability than SPRC both in vitro and in vivo, and the prolonged SPRC releasing could further promote the release of H2S in a sustained manner through CSE/H2S pathway both in vitro and in vivo. Importantly, the SPRC@DMSN showed promising anti-inflammation effect against AIA in rats was also observed. Conclusions A sustained H2S releasing donor consisting of SPRC and DMSN was constructed in this study, and this sustained H2S releasing donor might be of good use for the treatment of AIA.

Abstract Background Curcumin, a natural polyphenolic substance, has been known for more than two millennia as having strong anti-inflammatory activity towards multiple ailments, including arthritis. The main drawback of curcumin is its poor solubility in water, which leads to low intestinal absorption and minimal bioavailability. In this study, we aimed to compare the anti-arthritic in vivo effect of different curcumin preparations – basic curcumin extract, micellar curcumin, curcumin mixture with piperine, and microencapsulated curcumin. Methods Arthritis was induced in Wistar rats by complete Freund’s adjuvant, and the severity of arthritis was evaluated daily using the arthritis score system. Curcumin preparations were given to animals per os daily for 20 consecutive days, starting at 6th day after arthritis induction. To determine the inflammatory background, pro-inflammatory cytokines were determined using the ELISA test. In addition, hematologic test, weight change, and limb swelling were tracked. Results Our results indicate that curcumin had a rather weak effect on arthritis progression in the Wistar rat model, microencapsulated curcumin effectively prevented the progression of arthritis – the disease stabilized after 10 days of supplementation. It also reduced the levels of immune cells (neutrophils and leukocytes), as well as pro-inflammatory cytokines – TNFα, IL-1, and IL-6, which levels were close to arthritis-free control. Other formulations of curcumin had lower or no effect on arthritis progression. Conclusion Our study shows that the same concentrations of curcumin had a distinctly expressed positive anti-inflammatory effect depending on the form of its delivery. Specifically, we found that microencapsulated curcumin had the most promising effect for treatment. Graphical abstract

This study evaluated the protective effect of different dietary ω-6/ω-3 ratios in oils obtained from various nuts (walnut, peanut, cashew, and hazelnut) against morphological features and markers of inflammation on an adjuvant-induced arthritis rat model. Rheumatoid arthritis (RA) was induced via intradermal injection of heat-killed Mycobacterium tuberculosis. Five groups of rats with RA (n = 5) were randomly categorized as follows: control positive, walnut oil group, peanut oil group, cashew nut oil group, and hazelnut oil group. Another five healthy rats served as a normal non-arthritic (control) group. We assessed the therapeutic effects by measuring arthritis scores during the experiment and serum inflammatory markers at the end of the study. The serum levels of the rheumatoid factor, TNF-α, IL-6, IL-1β, and PGE2, were significantly (p ≤ 0.05) reduced in all treatment groups. The daily consumption of nut oils ameliorates clinical and morphological abnormalities by inhibiting the inflammatory cells that produce inflammatory interleukins and eicosanoids.

Background: Rheumatoid Arthritis (RA) is a chronic systemic autoimmune disease. According to Traditional Chinese Medicine (TCM) syndromes theory, moist heat arthralgia spasm syndrome is the most prevalent syndrome of RA patients in the active period. However, the mechanism of alteration of gut microbiota in RA with moist heat arthralgia spasm syndrome has not been reported until now., Objective: This study focused on the alteration of gut microbiota in adjuvant-induced arthritis rats with moist heat arthralgia spasm syndrome, elaborated its regulation mechanism, and analyzed the associations between gut microbiota and microbial metabolites., Methods: The disease-syndrome combination rat model of RA with moist heat arthralgia spasm syndrome was constructed with Adjuvant-Induced Arthritis (AIA) under damp-heat stimulating. Enzyme-Linked Immunosorbent Assay (ELISA) was used to measure serum biochemical indicators. Damages of ankle joints were observed using hematoxylin and eosin (H&E). 16 small ribosomal subunit RNA (16S rRNA) gene sequencing was conducted to assess the gut microbiota composition and function on feces from rats. Alterations in fecal metabolites profiling were evaluated by fecal metabolomics through Liquid Chromatography-Mass Spectrometry (LC-MS) and Gas Chromatography-Mass Spectrometry (GC-MS). Pearson correlation analysis was performed to explore the associations of altered gut microbiota and microbial metabolites in Model rats., Results: The imbalance of gut microbiota in Model rats was accompanied by metabolic disorders. Lactobacillus, Prevotellaceae&#95;NK3B31&#95;group, Allobaculum, Prevotellaceae&#95;UCG&#95;001, Alloprevotella, and Dubosiella were found to be dominant genera in Model rats. In total, 357 metabolites were significantly altered in Model rats and predominantly enriched into fatty acid degradation and glycerophospholipid metabolism. Pearson correlation analysis showed that TNF-α and IL-1β were associated with Prevotellaceae&#95;Ga6A1&#95;group and 3R-hydroxy-docosan-5S-olide, alpha-N-(3-hydroxy-14-methyl-pentadecanoyl)-ornithine, 17-methyl-trans-4,5- methylenenona-decanoic acid, Semiplenamide F., Conclusion: The key differential microbiota genera and differential microbial metabolites may become important targets for the treatment of RA and provide the theoretical basis for exploring the pathogenesis of RA., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Rheumatoid arthritis (RA) is characterized by systemic inflammation and synovial hyperplasia. Pristimerin, a natural triterpenoid isolated from plants belonging to the Celastraceae and Hippocrateaceae families, has been reported to exhibit anti-inflammation and anti-proliferation activities. Our study aims to reveal the antiarthritic effects of pristimerin and explore its potential mechanism using in vitro, in silico, and in vivo methods. In the present study, pristimerin treatment led to a dose-dependent decrease in cell viability and migration in TNF-α stimulated human rheumatoid arthritis fibroblast-like synoviocytes MH7A. Moreover, UPLC-LTQ-Orbitrap-based cell metabolomics analysis demonstrated that phospholipid biosynthesis, fatty acid biosynthesis, glutathione metabolism and amino acid metabolic pathways were involved in TNF-α induced MH7A cells after pristimerin treatment. In addition, the adjuvant–induced arthritis (AIA) rat model was employed, and the results exhibited that pristimerin could effectively relieve arthritis symptoms and histopathological damage as well as reduce serum levels of TNF-α, NO and synovial expressions of p-Akt and p-Erk in AIA rats. Furthermore, network pharmacology analysis was performed to visualize crucial protein targets of pristimerin for RA treatment, which showed that the effects were mediated through the MAPK/Erk1/2, PI3K/Akt pathways and directing binding with TNF-α. Taken together, our study not only offered new insights into the biochemical mechanism of natural compounds for RA treatment, but also provided a strategy that integrated in vitro, in silico and in vivo studies to facilitate screening of new anti-RA drugs.

Background: Rheumatoid arthritis (RA) is a kind of chronic autoimmune disease with several tissues damaged. Shuji tablet (SJT) is a prescription approved for treating lumbago and leg pain in the clinic. However, the efficacy of SJT against RA is still unknown. This study aims to evaluate the therapeutic effect of SJT on adjuvant-induced arthritis (AIA) rats and explore the mechanism via a network pharmacological approach.Methods: AIA rats were treated with SJT for 30 days at the dosages of 3.6, 1.8, and 0.9 g/kg, respectively, and the anti-RA effect was determined by measuring paw swelling, systemic symptoms score, arthritis index, and histopathological change. ELISA assay was used to evaluate the level of inflammatory cytokines in serum. The mechanism exploration and target prediction of SJT against RA were performed via a network pharmacological approach.Results: SJT showed excellent alleviation on AIA rats, with evidence of reducing paws swelling, decreasing systemic symptoms score, and arthritis index. Furthermore, SJT significantly reduced the serum cytokines of IL-6, IL-1β, TNF-α in AIA rats. Histopathological examination showed SJT remarkably reduced synovial hyperplasia, cartilage damage, and inflammatory infiltration in the secondary-side paws. According to network pharmacological analysis, 208 candidate compounds and 445 potential targets of SJT were identified, and 4465 RA therapy-related targets were searched out. Subsequently, 292 target genes of SJT were speculated to be associated with RA treatment, among which the top 5 “response values” targets were STAT3, AKT1, JUN, HSP90AA1, TNF. GO and KEGG enrichment analysis suggested that 45 signaling pathways were associating with SJT treating RA. The top 10 signaling pathways were PI3K-Akt, MAPK, AGE-RAGE pathway in diabetic complications, Ras, HIF-1, TNF, Chemokine, IL-17, FoxO, and Rap1.Conclusion: Our experimental study showed that SJT significantly alleviated rheumatoid arthritis of AIA rats. Network pharmacology showed that the key targets of SJT against RA probably were STAT3, AKT1, JUN, HSP90AA1, TNF, and the potential mechanism was associated with modulation on the signaling pathways of PI3K-Akt, MAPK, Ras, AGE-RAGE, HIF-1, TNF, chemokine, IL-17, FoxO, Rap 1. Our study strongly provides evidence for Shuji tablet in RA therapy and would enlarge its application in the clinic.

In the pathogenesis of rheumatoid arthritis (RA), rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) have tumor-like characteristics, mainly manifested by hyperproliferation and resistance to apoptosis and then it will erode the bone and cartilage, eventually leading to joint destruction. Paris saponin VII (PS VII) is an active compound derived from a traditional herbal medicine named Trillium tschonoskii Maxim, which has anti-tumor, analgesic, and immunomodulatory effects. However, its anti-RA effect has not yet been reported. This study was to investigate the effect of PS VII on two rheumatoid arthritis fibroblast-like synoviocytes lines (RA-FLS and MH7A) and adjuvant-induced arthritis (AIA) in rats. In vitro, the effects of PS VII on the proliferation, cell cycle, and apoptosis of RA-FLS and MH7A cells were detected by MTT, flow cytometry, and western blot analysis. In vivo, the effect of PS VII on the weight of the rat, paw swelling, ankle joint diameter, arthritis index, serum inflammatory cytokines (TNF-α, IL-6, and IL-1β), histopathological assessment and apoptosis proteins in the synovial tissues were evaluated in AIA rats. The in vitro studies showed that PS VII inhibited the proliferation of RA-FLS and MH7A cells, induced S phase arrest and triggered cell apoptosis mainly through the mitochondrial apoptotic pathway and the regulation of JNK and p38 MAPK pathways. The in vivo studies revealed that PS VII could improve ameliorate body weight, paw swelling, ankle joint diameter, reduce the spleen and thymus index, suppress the production of TNF-α, IL-6 and IL-1β, improve histopathological changes and regulate the expressions of apoptosis proteins in AIA Rats. In conclusion, PS VII could inhibit the proliferation and trigger apoptosis of RA-FLS and MH7A cells by regulating the mitochondrial apoptosis pathway and the JNK and p38 MAPK pathways, and alleviate the symptoms of RA, signifying it to be one of the potential anti-RA therapeutics.

Background: Rheumatoid arthritis (RA) is a kind of chronic autoimmune disease with several tissues damaged. Shuji tablet (SJT) is a prescription approved for treating lumbago and leg pain in the clinic. However, the efficacy of SJT against RA is still unknown. This study aims to evaluate the therapeutic effect of SJT on adjuvant-induced arthritis (AIA) rats and explore the mechanism via a network pharmacological approach. Methods: AIA rats were treated with SJT for 30 days at the dosages of 3.6, 1.8, and 0.9 g/kg, respectively, and the anti-RA effect was determined by measuring paw swelling, systemic symptoms score, arthritis index, and histopathological change. ELISA assay was used to evaluate the level of inflammatory cytokines in serum. The mechanism exploration and target prediction of SJT against RA were performed via a network pharmacological approach. Results: SJT showed excellent alleviation on AIA rats, with evidence of reducing paws swelling, decreasing systemic symptoms score, and arthritis index. Furthermore, SJT significantly reduced the serum cytokines of IL-6, IL-1β, TNF-α in AIA rats. Histopathological examination showed SJT remarkably reduced synovial hyperplasia, cartilage damage, and inflammatory infiltration in the secondary-side paws. According to network pharmacological analysis, 208 candidate compounds and 445 potential targets of SJT were identified, and 4465 RA therapy-related targets were searched out. Subsequently, 292 target genes of SJT were speculated to be associated with RA treatment, among which the top 5 "response values" targets were STAT3, AKT1, JUN, HSP90AA1, TNF. GO and KEGG enrichment analysis suggested that 45 signaling pathways were associating with SJT treating RA. The top 10 signaling pathways were PI3K-Akt, MAPK, AGE-RAGE pathway in diabetic complications, Ras, HIF-1, TNF, Chemokine, IL-17, FoxO, and Rap1. Conclusion: Our experimental study showed that SJT significantly alleviated rheumatoid arthritis of AIA rats. Network pharmacology showed that the key targets of SJT against RA probably were STAT3, AKT1, JUN, HSP90AA1, TNF, and the potential mechanism was associated with modulation on the signaling pathways of PI3K-Akt, MAPK, Ras, AGE-RAGE, HIF-1, TNF, chemokine, IL-17, FoxO, Rap 1. Our study strongly provides evidence for Shuji tablet in RA therapy and would enlarge its application in the clinic. [ABSTRACT FROM AUTHOR]

Clinically, Wangbi Capsule (WBC) is widely used in the treatment of Rheumatoid arthritis (RA) because of its remarkable therapeutic effect. To reveal the mechanism, a pharmacokinetic–pharmacodynamic (PK–PD) model was developed for the first time to assess the relationship between time–concentration (dose)–effect. Freund's Complete Adjuvant was used to induce the adjuvant‐induced arthritis model. Multi‐indices were used to evaluate the therapeutic effect and an S‐Imax PK–PD model was established based on the concentrations of osthole, 5‐O‐methylvisamminoside, cimifugin, albiflorin, paeoniflorin and icariin and the levels of interleukin‐1β and prostaglandin E2 using a two‐compartment PK model together with a PD model with an effect‐site compartment. The results suggest that WBC can treat RA by regulating the levels of prostaglandin E2 and interleukin‐1β. For the PK–PD model, the parameters indicated that WBC had a large safety margin and all six bioactive ingredients of WBC have therapeutic effects on RA. Among them icariin, osthole and 5‐O‐methylvisamminoside may be the main effective substances. This study provided a scientific basis for further study of population pharmacokinetics / population pharmacodynamics (PPK/PPD), to develop a reasonable administration plan and improve individualized drug therapy. [ABSTRACT FROM AUTHOR]

In the pathogenesis of rheumatoid arthritis (RA), rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) have tumor-like characteristics, mainly manifested by hyperproliferation and resistance to apoptosis and then it will erode the bone and cartilage, eventually leading to joint destruction. Paris saponin VII (PS VII) is an active compound derived from a traditional herbal medicine named Trillium tschonoskii Maxim, which has anti-tumor, analgesic, and immunomodulatory effects. However, its anti-RA effect has not yet been reported. This study was to investigate the effect of PS VII on two rheumatoid arthritis fibroblast-like synoviocytes lines (RA-FLS and MH7A) and adjuvant-induced arthritis (AIA) in rats. In vitro , the effects of PS VII on the proliferation, cell cycle, and apoptosis of RA-FLS and MH7A cells were detected by MTT, flow cytometry, and western blot analysis. In vivo , the effect of PS VII on the weight of the rat, paw swelling, ankle joint diameter, arthritis index, serum inflammatory cytokines (TNF-α, IL-6, and IL-1β), histopathological assessment and apoptosis proteins in the synovial tissues were evaluated in AIA rats. The in vitro studies showed that PS VII inhibited the proliferation of RA-FLS and MH7A cells, induced S phase arrest and triggered cell apoptosis mainly through the mitochondrial apoptotic pathway and the regulation of JNK and p38 MAPK pathways. The in vivo studies revealed that PS VII could improve ameliorate body weight, paw swelling, ankle joint diameter, reduce the spleen and thymus index, suppress the production of TNF-α, IL-6 and IL-1β, improve histopathological changes and regulate the expressions of apoptosis proteins in AIA Rats. In conclusion, PS VII could inhibit the proliferation and trigger apoptosis of RA-FLS and MH7A cells by regulating the mitochondrial apoptosis pathway and the JNK and p38 MAPK pathways, and alleviate the symptoms of RA, signifying it to be one of the potential anti-RA therapeutics. [ABSTRACT FROM AUTHOR]

Summary: Despite undeniable improvement in the management of rheumatoid arthritis (RA), the discovery of more effective, less toxic and, ideally, less immune suppressive drugs are much needed. In the current study, we set to explore the potential anti‐rheumatic activity of the non‐toxic, tellurium‐based immunomodulator, AS101 in an experimental animal model of RA. The effect of AS101 was assessed on adjuvant‐induced arthritis (AIA) rats. Clinical signs of arthritis were assessed. Histopathological examination was used to assess inflammation, synovial changes and tissue lesions. Very late antigen‐4 (VLA‐4)+ cellular infiltration was detected using immunohistochemical staining. Enzyme‐linked immunosorbent assay (ELISA) was used to measure circulating anti‐cyclic citrullinated‐peptide autoantibody (ACPA) and real‐time polymerase chain reaction (PCR) was used to measure the in‐vitro effect of AS101 on interleukin (IL)‐6 and IL‐1β expression in activated primary human fibroblasts. Prophylactic treatment with intraperitoneal AS101 reduced clinical arthritis scores in AIA rats (P < 0·01). AS101 abrogated the migration of active chronic inflammatory immune cells, particularly VLA‐4+ cells, into joint cartilage and synovium, reduced the extent of joint damage and preserved joint architecture. Compared to phosphate‐buffered saline (PBS)‐treated AIA rats, histopathological inflammatory scores were significantly reduced (P < 0·05). Furthermore, AS101 resulted in a marked reduction of circulating ACPA in comparison to PBS‐treated rats (P < 0·05). Importantly, AS101 significantly reduced mRNA levels of proinflammatory mediators such as IL‐6 (P < 0·05) and IL‐1β (P < 0·01) in activated primary human fibroblasts. Taken together, we report the first demonstration of the anti‐rheumatic/inflammatory activity of AS101 in experimental RA model, thereby supporting an alternative early therapeutic intervention and identifying a promising agent for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic autoimmune, multifactorial, inflammatory disorder characterized by hyperplasia and infiltration of inflammatory cells at the synovial lining leading to destruction of cartilage and bone tissues. Pinocembrin (PCB) is a natural flavonoid extracted as a pure molecule from honey, propolis, and some plants. In this study, we evaluated the antiarthritic effect of PCB in adjuvant induced arthritis (AIA) mice. Treating the AIA mouse model with PCB reduced the arthritis symptoms/score, including edema size, extent of hind paw redness, abnormal movement, and holding inability. At the pathological level, PCB significantly decreased the joint erosion and percentages of infiltrated inflammatory cells. Biochemically, PCB interacts with the transcription factor, SRY-related HMG-box 4 (Sox4), and then modulates its dysregulated expression and the expression of Sox4/Stat3 signaling molecules in AIA mice. These molecules include tumor necrosis factor-α, nuclear transcription factor kappaB, and cyclooxygenase-2, besides the microRNAs; miR-132, miR-202-5p, and miR-7235, which are dysregulated in adjuvant-induced arthritis model relative to the control mice. The possible PCB interaction with Sox4 transcriptional protein was confirmed through molecular docking where three hydrogen bonds were formed at ARG and LYS residues at a stable binding energy of −4.72. Taken together, our data demonstrate that PCB could serve as a therapeutic drug in treatment of RA. [ABSTRACT FROM AUTHOR]

The class III histone deacetylase sirtuin 1 (SIRT1) plays a pivotal role in numerous biological and physiological functions, including inflammation. An association between SIRT1 and proinflammatory cytokines might exist. In addition to their important role in inflammation associated with rheumatoid arthritis (RA), proinflammatory cytokines mediate the development of systemic effects. Here, we evaluated systemic SIRT1 expression and enzymatic activity, in peripheral blood mononuclear cells (PBMCs) and in liver isolated from rats with adjuvant-induced arthritis (AIA), treated or not with low or high doses of glucocorticoids (GCs). We also measured the production of tumour necrosis factor alpha (TNF) and interleukin-1 beta (IL-1 beta) in PBMCs and liver. We found that SIRT1 expression and activity increased in PBMCs of AIA rats compared to healthy controls and decreased under GC treatment. Similarly, we observed an increased SIRT1 activity in the liver of AIA rats compared to healthy controls which decreased under high doses of GCs. We also found an increase in IL-1 beta and TNF levels in the liver of AIA rats compared to healthy controls, which decreased under high doses of GC. We did not observe a significant correlation between SIRT1 activity and proinflammatory cytokine production in PBMC or liver. In contrast, a strong positive correlation was found between the liver levels of TNF and IL-1 beta (rho=0.9503, p=7.5x10−21). Our results indicate that increased inflammation in AIA rats compared to healthy control is accompanied by an increased SIRT1 activity in both PBMCs and liver, which could be decreased under GC treatment. [ABSTRACT FROM AUTHOR]

Background: We previously demonstrated that celastrol has significant anti-inflammatory and bone protective effects when administered via the intraperitoneal route. For further preclinical evaluation, an effective oral administration of celastrol is crucial. Here we aimed to study the therapeutic dose range for its oral administration.Methods: Celastrol (1–25 μg/g/day, N = 5/group) was administrated orally to female adjuvant-induced arthritis (AIA) rats after 8 days of disease induction for a period of 14 days. A group of healthy (N = 8) and arthritic (N = 15) gender- and age-matched Wistar rats was used as controls. During the treatment period, the inflammatory score, ankle perimeter, and body weight were measured. At the end of the treatment, the animals were sacrificed, blood was collected for clinical pathology, necropsy was performed with collection of internal organs for histopathological analysis, and paw samples were used for disease scoring.Results: Doses higher than 2.5 μg/g/day of celastrol reduced the inflammatory score and ankle swelling, preserved joint structure, halted bone destruction, and diminished the number of synovial CD68+ macrophages. Bone resorption and turnover were also reduced at 5 and 7.5 μg/g/day doses. However, the dose of 7.5 μg/g/day was associated with thymic and liver lesions, and higher doses showed severe toxicity.Conclusion: Oral administration of celastrol above 2.5 μg/g/day ameliorates arthritis. This data supports and gives relevant information for the development of a preclinical test of celastrol in the setting of a chronic model of arthritis since rheumatoid arthritis is a long-term disease.

Rheumatoid arthritis (RA) is among the most prevalent forms of autoimmunity. Gentiopicroside (Gent) is an iridoid glucoside derived from the Gentiana Macrophylla Pall which is used in traditional Chinese medicine to treat RA. The present study was designed to explore the ability of Gent to combat RA and to explore the molecular basis for such anti-RA activity both in vitro using tumor necrosis factor alpha (TNF-α)-stimulated human RA fibroblast-like synoviocytes (RA-FLS) and in vivo using a rat adjuvant-induced arthritis (AIA) model. We found that Gent was able to significantly reduce the swelling of joints and arthritic index scores, with corresponding reductions in synovial inflammatory cell infiltration, synovial hyperplasia, and bone erosion in treated AIA rats. Importantly, Gent 200 mg/kg reduced thymus index in AIA rats, but had no effect on spleen index and body weight, it revealed that Gent was relatively safe at the dose we chose. We further found that Gent was able to suppress the TNF-α-induced proliferation and migration of RA-FLS cells. This suppression was attributed to the ability of Gent to block NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), and caspase-1, thereby disrupting the activation of the NLRP3 inflammasome. Consistent with such suppression, Gent led to a significant decrease in IL-1β secretion by treated cells. Furthermore, this reduction in NLRP3 inflammasome activation was also associated with decreases in the activation of nuclear factor (NF-κB), the production of reactive oxygen species (ROS), and the expression of inflammatory IL-6. Together these findings indicate that Gent can suppress the ROS-NF-κB-NLRP3 axis to alleviate RA symptoms.Chemical compounds studied in this articleGentiopicroside (PubChem CID: 88708).

Though the exact etiology of rheumatoid arthritis (RA) is unknown, the contribution of immune cells in the disease process is completely acknowledged. T helper (Th) 1 and Th17-related cytokines are required for the disease development and progression, while Th2 and regulatory T cells (Tregs)-derived cytokines are protective. Studies have shown that sodium benzoate (NaB) can switch the balance of Th cell subsets toward Th2 and Tregs. The present study aimed to evaluate the possible effects of NaB on the expression of CD4+T cells-related cytokines and transcription factors in splenocytes derived from an animal model of RA, adjuvant-induced arthritis (AIA). AIA was induced in rats by injection of Freund's adjuvant containing mycobacterial antigens (Mtb). Splenocytes were isolated from AIA rats and restimulated ex vivo with Mtb in the presence or absence of NaB for 24 h. To determine the effects of NaB on the expression of T cells-related cytokine and transcription factor genes, real-time PCR was performed. NaB treatment of Mtb-stimulated splenocytes derived from arthritic rats resulted in significant increases in the gene expressions of Tregs-related cytokines (IL-10 and TGF-β) and Foxp3 transcription factor, and significant decreases in the expression of Th1-related cytokines (TNF-α and IFN-γ) and the T-bet transcription factor. The ratios of Th1/Th2 (IFN-γ/IL-4), Th1/Treg (IFN-γ/TGF-β and IFN-γ/IL-10) and Th17/Treg (IL-17/IL-10 and IL-17/IL-10+TGF-β)-related cytokines were also significantly decreased. In conclusion, NaB can potentially be considered as a useful therapeutic agent for the treatment of RA and other Th1 and Th17-mediated diseases.

Abstract Background Rheumatoid arthritis (RA) being an incapacitating disease requires early effective intervention. Considering Methotrexate (MTX)- the first line of treatment for RA- intoxicates the liver; therefore, alternative therapies with similar efficacy yet lower cytotoxicity are desired. Indole-3-Carbinol (I3C) which is found in cruciferous vegetables was examined for its possible therapeutic potentials in comparison with MTX by investigating its anti-inflammatory, anti-arthritic, anti-oxidant, and hepatoprotective potentials in adjuvant-induced arthritis (AIA) rat model. Methods Arthritis was induced in Sprague Dawley rats by injection of Complete Freund’s Adjuvant (CFA). Arthritic rats were treated with I3C and/or MTX. To examine the anti-inflammatory and anti-arthritic effect, the following parameters were assessed: body weight, macroscopic scoring of the hind paw, the level of the pivotal cytokines (TNF-α, IL-6) heavily involved in the pathogenesis, spleen index, and erythrocyte sedimentation rate. At a histological level, the tibiotarsal joint was stained with several specific stains. To assess the hepatoprotective and anti-oxidant effects, several oxidative stress parameters were monitored, and the liver histology was examined. Results Both I3C and MTX attenuated the inflammation that was aggravated by arthritis by downregulating the inflammatory markers and mediators and alleviating the histopathological changes affecting the tibiotarsal joint. I3C attenuated the liver impairment that was initiated by arthritis and MTX treatment. It did so by downregulating the pro-oxidants and up-regulating the anti-oxidant defenses and by reducing the pathological changes affecting the liver. Conclusion Our results suggest that I3C is as potent as MTX as an anti-inflammatory and anti-arthritic agent. In addition, I3C does so while protecting the liver from damage as opposed to MTX.

Our previous study showed that up-regulated DNA methyltransferase-1 (DNMT1) played an important role in the hypermethylation modification of SFRP4 in adjuvant-induced arthritis (AIA) rats. This work focused on the role of disordered miR-148b-3p in RA pathology and its corresponding regulatory targets. The expression of miR-148b-3p and DNMT1, and the effect of miR-148b-3p on the DNMT1 expression were determined by real-time qPCR, western blotting and double luciferase reporter genes. The role of miR-148b-3p on the SFRP4 expression, the canonical Wnt signaling and the pathology of AIA rats was investigated using real-time qPCR, western blotting and methylation-specific PCR (MSP). The results showed that the expression of miR-148b-3p was significantly decreased, the expression of DNMT1 was significantly increased and the DNMT1 was the direct target of miR-148b-3p in AIA rats compared with normal group. Transfection of miR-148b-3p mimics up-regulated the SFRP4 expression, inhibited the canonical Wnt signaling and the pathogenesis of AIA rats by targeting the DNMT1. The role of miR-148b-3p knockdown was opposite to that of miR-148b-3p overexpression. These results suggest that miR-148b-3p may influence the pathogenesis of RA with the DNMT1 as a direct target and miR-148b-3p may be a potential diagnostic and therapeutic target for RA patients.

Background: Curcumin, a natural polyphenolic substance, has been known for more than two millennia as having strong anti-inflammatory activity towards multiple ailments, including arthritis. The main drawback of curcumin is its poor solubility in water, which leads to low intestinal absorption and minimal bioavailability. In this study, we aimed to compare the anti-arthritic in vivo effect of different curcumin preparations – basic curcumin extract, micellar curcumin, curcumin mixture with piperine, and microencapsulated curcumin. Methods: Arthritis was induced in Wistar rats by complete Freund's adjuvant, and the severity of arthritis was evaluated daily using the arthritis score system. Curcumin preparations were given to animals per os daily for 20 consecutive days, starting at 6th day after arthritis induction. To determine the inflammatory background, pro-inflammatory cytokines were determined using the ELISA test. In addition, hematologic test, weight change, and limb swelling were tracked. Results: Our results indicate that curcumin had a rather weak effect on arthritis progression in the Wistar rat model, microencapsulated curcumin effectively prevented the progression of arthritis – the disease stabilized after 10 days of supplementation. It also reduced the levels of immune cells (neutrophils and leukocytes), as well as pro-inflammatory cytokines – TNFα, IL-1, and IL-6, which levels were close to arthritis-free control. Other formulations of curcumin had lower or no effect on arthritis progression. Conclusion: Our study shows that the same concentrations of curcumin had a distinctly expressed positive anti-inflammatory effect depending on the form of its delivery. Specifically, we found that microencapsulated curcumin had the most promising effect for treatment. [ABSTRACT FROM AUTHOR]

Anethole (AN) is a natural compound that has attracted great scientific interest because of its numerous biological activities, including anti-inflammatory effects. However, these effects were obtained with high doses of AN, which may be one limitation of its therapeutic use. This study evaluated the effects of a low-dose AN and ibuprofen (IB) combination on inflammatory parameters in Freund's complete adjuvant-induced arthritis (AIA) and arthritis-induced hepatic metabolic changes. Holtzman rats were used and divided into groups: normal, AIA (control), arthritics treated with IB, arthritics treated with AN, and arthritics treated with AN + IB. The volume of the paws, the appearance of secondary lesions, and the number of synovial leukocytes were evaluated. Gluconeogenesis and ureagenesis from alanine were determined in the rat liver in isolated perfusion. The AN + IB (62.5 + 8.75 mg/kg) treatment exerted an inhibitory effect on inflammatory parameters and partially prevented hepatic metabolic changes that was similar to the effect of high-dose IB (35 mg/kg) and AN (250 mg/kg) treatment. This effect of the treatments on hepatic metabolism can be, partly at least, explained by the preservation of both the alanine aminotransferase (ALT) activity and the cytosolic NADH/NAD+ redox potential in the liver. Taken together, the data obtained provided evidence that the AN + IB combination at lower doses than AN and IB treatment alone had beneficial inhibitory potential for the treatment of AIA and attenuated metabolic changes in the liver. [ABSTRACT FROM AUTHOR]

Activated macrophages are the primary targets in rheumatoid arthritis (RA) management. So, we report efficacious, dual-functional Methotrexate (MTX) loaded folate-conjugated pH-responsive glycol-chitosan nanoparticles (MFGCN) prepared by nano-precipitation and zero-order cross-linking reaction for targeting inflamed arthritic tissue. Physical characterization by DLS, SEM and TEM indicated a spherical, smooth morphology with a diameter ~ 300 nm. 1H NMR and FTIR indicated folic acid conjugation to GC by zero-order cross-linkers. In vitro release kinetics in PBS showed pH-responsive and sustained release behaviour of MFGCN. Enhanced cellular uptake and cytotoxicity of MFGCN in LPS(+)RAW and activated peritoneal macrophages (Mϕ) were observed when compared to LPS(−)RAW cells. MFGCN-induced mitochondrial membrane potential (MMP) perturbations indicated apoptosis. Oxidative stress was evident by significant increase in ROS and RNS, 4 h post incubation with MFGCN. Negligible hemolysis by FGCN and MFGCN on rat RBC's indicated biocompatibility. In vivo biodistribution of MFGCN in adjuvant-induced arthritis (AIA) rats indicated RA targetability. Prolonged blood circulation coupled with higher concentrations of 99mTc-MFGCN at the arthritic site was observed post 24 h of injection. The gamma scintigraphic image confirmed accumulation of radiolabelled MFGCN in arthritic paw when compared to the non-inflamed paw, confirming the selective uptake of 99mTc-MFGCN by folate-overexpressing macrophages in the arthritic synovium thereby proving its targeted efficacy and theranostic potential. In AIA rats, MFGCN lowers arthritic signs, improves antioxidant response and decreases pro-inflammatory cytokines, suggesting its potential in targeting activated macrophages of synovium. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic autoimmune disease of idiopathic etiology that triggers inflammatory cytokines compromising the joint mobility. Epidemiological evidences recommend the utilization of galantamine (GH) to reverse the anti-inflammatory reactions induced RA. Oral administration of GH is non-selectivity due to its association with serious gastrointestinal symptoms which, could hinder its therapeutic success. Therefore, the present study aimed to validate the therapeutic potential of GH transdermal patches as a novel application to constitute an effective and tolerable delivery system for managing RA in adjuvant arthritis model. RA was induced in Sprague-Dawley rats intradermally by Heat-killed M (0.12 ml/day). Oral GH (1.25 mg/kg/day) and GH transdermal patch (2.5 mg/kg/2 days) were administrated for 14 days, during which the hind paw and body weight (BW) were assessed. Effects of C-reactive protein (CRP), inflammatory cytokines (TNF-α, IL-10 and IL-1β) and Janus kinase (JAK-2) were evaluated. Oral- and transdermal GH significantly improved the hind paw edema in arthritis animal model and offered a protective impact against RA. Oral GH group showed marked decrease in BW than that of transdermal patches group. Transdermal patch group showed a significant decrease in the level of IL-1β more than the oral group. However, no significant difference was detected in the levels of TNF-α and IL-10 between the two groups. It is concluded that GH transdermal patch can be a promising drug delivery system that copes with side effects better than oral GH consequently represents novel strategy in management of RA. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is among the most prevalent forms of autoimmunity. Gentiopicroside (Gent) is an iridoid glucoside derived from the Gentiana Macrophylla Pall which is used in traditional Chinese medicine to treat RA. The present study was designed to explore the ability of Gent to combat RA and to explore the molecular basis for such anti-RA activity both in vitro using tumor necrosis factor alpha (TNF-α)-stimulated human RA fibroblast-like synoviocytes (RA-FLS) and in vivo using a rat adjuvant-induced arthritis (AIA) model. We found that Gent was able to significantly reduce the swelling of joints and arthritic index scores, with corresponding reductions in synovial inflammatory cell infiltration, synovial hyperplasia, and bone erosion in treated AIA rats. Importantly, Gent 200 mg/kg reduced thymus index in AIA rats, but had no effect on spleen index and body weight, it revealed that Gent was relatively safe at the dose we chose. We further found that Gent was able to suppress the TNF-α-induced proliferation and migration of RA-FLS cells. This suppression was attributed to the ability of Gent to block NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), and caspase-1, thereby disrupting the activation of the NLRP3 inflammasome. Consistent with such suppression, Gent led to a significant decrease in IL-1β secretion by treated cells. Furthermore, this reduction in NLRP3 inflammasome activation was also associated with decreases in the activation of nuclear factor (NF-κB), the production of reactive oxygen species (ROS), and the expression of inflammatory IL-6. Together these findings indicate that Gent can suppress the ROS-NF-κB-NLRP3 axis to alleviate RA symptoms. Chemical compounds studied in this article: Gentiopicroside (PubChem CID: 88708). [ABSTRACT FROM AUTHOR]

Though the exact etiology of rheumatoid arthritis (RA) is unknown, the contribution of immune cells in the disease process is completely acknowledged. T helper (Th) 1 and Th17- related cytokines are required for the disease development and progression, while Th2 and regulatory T cells (Tregs)-derived cytokines are protective. Studies have shown that sodium benzoate (NaB) can switch the balance of Th cell subsets toward Th2 and Tregs. The present study aimed to evaluate the possible effects of NaB on the expression of CD4+T cells-related cytokines and transcription factors in splenocytes derived from an animal model of RA, adjuvant-induced arthritis (AIA). AIA was induced in rats by injection of Freund's adjuvant containing mycobacterial antigens (Mtb). Splenocytes were isolated from AIA rats and restimulated ex vivo with Mtb in the presence or absence of NaB for 24 h. To determine the effects of NaB on the expression of T cells-related cytokine and transcription factor genes, real-time PCR was performed. NaB treatment of Mtb-stimulated splenocytes derived from arthritic rats resulted in significant increases in the gene expressions of Tregs-related cytokines (IL-10 and TGF-ß) and Foxp3 transcription factor, and significant decreases in the expression of Th1-related cytokines (TNF-a and IFN-?) and the T-bet transcription factor. The ratios of Th1/Th2 (IFN-?/IL-4), Th1/Treg (IFN-?/TGF-ß and IFN-?/IL-10) and Th17/Treg (IL-17/IL-10 and IL-17/IL-10+TGF-ß)-related cytokines were also significantly decreased. In conclusion, NaB can potentially be considered as a useful therapeutic agent for the treatment of RA and other Th1 and Th17-mediated diseases. [ABSTRACT FROM AUTHOR]

[Display omitted] • The VEGFR2 inhibitor CPD-002 relieved HUVEC migration, invasion, and chemotaxis. • CPD-002 administration mitigated the severity and development of AIA in rats. • CPD-002 inhibited angiogenesis in HUVECs, ex vivo, and within AIA rat synovium. • CPD-002 blocked VEGFR2/PI3K/AKT axis activation in HUVECs and AIA synovium. • CPD-002′s anti-inflammatory effects contributed to its anti-angiogenic functions. Synovial angiogenesis is a key player in the development of rheumatoid arthritis (RA), and anti-angiogenic therapy is considered a promising approach for treating RA. CPD-002 has demonstrated efficacy in suppressing tumor angiogenesis as a VEGFR2 inhibitor, but its specific impacts on RA synovial angiogenesis and possible anti-RA effects need further study. We examined the influences of CPD-002 on the migration and invasion of human umbilical vein endothelial cells (HUVECs) and its impacts on HUVECs' tube formation and vessel sprouting ex vivo. The therapeutic potential of CPD-002 in adjuvant-induced arthritis (AIA) rats and its suppression of synovial angiogenesis were examined. The involvement of the VEGFR2/PI3K/AKT pathway was assessed both in HUVECs and AIA rat synovium. Here, CPD-002 inhibited the migration and invasion of VEGF-stimulated HUVECs, decreased their chemotactic response to RA fibroblast-like synoviocyte-released chemoattractants, and exhibited anti-angiogenic effects in vitro and ex vivo. CPD-002′s targeting of VEGFR2 was confirmed with molecular docking and cellular thermal shift assays, supported by the abolishment of CPD-002′s effects upon using VEGFR2 siRNA. CPD-002 relieved paw swelling, arthritis index, joint damage, and synovial angiogenesis, indicating its anti-arthritic and anti-angiogenic effects in AIA rats. Moreover, the anti-inflammatory effects in vivo and in vitro of CPD-002 contributed to its anti-angiogenic effects. Mechanistically, CPD-002 hindered the activation of VEGFR2/PI3K/AKT pathway in VEGF-induced HUVECs and AIA rat synovium, as evidenced by reduced p-VEGFR2, p-PI3K, and p-AKT protein levels alongside elevated PTEN protein levels. Totally, CPD-002 showed anti-rheumatoid effects via attenuating angiogenesis through the inhibition of the VEGFR2/PI3K/AKT pathway. [ABSTRACT FROM AUTHOR]