Cytokines in the pathogenesis of rheumatoid arthritis and collagen-induced arthritis

Association between rheumatoid arthritis and pulpal-periapical pathology: a systematic review

OBJECTIVES

Rheumatoid arthritis (RA) is a debilitating disease where numerous pro-inflammatory cytokines have a proven role in its pathology. These cytokines are also involved in the pathogenesis of apical periodontitis (AP) where they have a pro-inflammatory role and induce bone resorption. Patients with RA may therefore be more prone to develop pulpal-periapical pathology (PPP). This study systematically reviewed the existing literature evaluating the association between RA and PPP.

MATERIALS AND METHODS

Studies including human participants with both RA and PPP were included. The search was performed in PubMed, Web of Science, and The Cochrane Library databases using keywords and Medical Subject Headings (MeSH) search terms. The risk of bias was assessed using Newcastle-Ottawa Quality Assessment Scale. The following parameters were extracted and analyzed by the reviewers; author, journal, year, design of the study, diagnostic criteria for periapical pathology, the association between rheumatoid arthritis and periapical pathology, and the evidence level.

RESULTS

The search identified 142 records. Inclusion criteria were as follows; studies in the English language, including human participants only, including patients with RA and PPP, cohort studies, cross-sectional studies, clinical trials, and case-control studies. According to the inclusion criteria, 5 studies were included in this systematic review. Three of the five studies reported significant association between RA and PPP.

CONCLUSIONS

Existing evidence suggests there may be an association between RA and PPP.

CLINICAL RELEVANCE

Clinicians should be aware that RA patients can be more prone to develop PPP which may result in a reduced quality of life.

Validation of traditional claims of anti-arthritic efficacy of trans-Himalayan snow mountain garlic (Allium ampeloprasum L.) extract using adjuvant-induced arthritis rat model: A comparative evaluation with normal garlic (Allium sativum L.) and dexamethasone

ETHNOPHARMACOLOGICAL RELEVANCE

Snow Mountain Garlic (SMG) (Allium ampeloprasum L.) is a wild trans-Himalayan member of the genus Allium, valued for its anti-inflammatory and anti-arthritic properties in the mountain folk medicinal system (Sowa-Rigpa). Despite its age-old medicinal usage by traditional therapists and the native population for various ailments including rheumatism, there is no scientific validation of its phyto-pharmaceutical merits.

AIM OF THE STUDY

The present pre-clinical study compared the in-vivo anti-arthritic effects of SMG with reported efficacy doses of normal garlic (Allium sativum L.) extract and dexamethasone in a complete Freund's adjuvant (CFA)-induced arthritis rat model.

MATERIALS AND METHODS

The female Wistar rats were immunized by the subplannter injection of CFA into the right hind footpad. Aqueous extracts of SMG and normal garlic were administered orally at a dose of 250 mg/kg and 500 mg/kg for 28 days. Dexamethasone was used as positive control drug. Behavioral parameters including paw markers, arthritis index, joint stiffness, body weight change, etc. were measured. Also, the changes in histopathological indices, hematological profile, inflammatory mediators, and serum cytokines level was determined.

RESULTS

Treatment of rats with SMG extracts significantly (p < 0.001) prevented the reduction in body weight and hematological changes as well as ameliorated clinical symptoms such as arthritic index, joint stiffness, arthritis score, edema, hyperalgesia, and histopathological indices. This was associated with a significant reduction in the serum levels of RF, CRP, anti-CCP, and proinflammatory cytokines exhibiting strong anti-arthritic potential. SMG extracts could also significantly down regulate the NF-κB, COX-2, and iNOS expression in the ankle joint tissues.

CONCLUSIONS

The present study is the first attempt to validate the phyto-pharmaceutical efficacy of this folk garlic variety from the trans-Himalayan region. Overall, SMG extract showed remarkable preventive anti-inflammatory and anti-arthritic activities which were closely comparable to therapeutic effects of dexamethasone and at par or even better than normal garlic w.r.t. several study parameters.

Resveratrol-Loaded Chia Seed Oil-Based Nanogel as an Anti-Inflammatory in Adjuvant-Induced Arthritis

Natural anti-inflammatory nutraceuticals may be useful in preventing rheumatoid arthritis from worsening. Resveratrol (RV) and chia seed oil, having antioxidant potential, can assist in avoiding oxidative stress-related disorders. This investigation developed and evaluated resveratrol-loaded chia seed oil-based nanoemulsion (NE) gel formulations through in vitro and in vivo studies. The physical stability and in vitro drug permeability of the chosen formulations (NE1 to NE10) were studied. The optimized RV-loaded nanoemulsion (NE2) had droplets with an average size of 37.48 nm that were homogeneous in shape and had a zeta potential of -18 mV. RV-NE2, with a permeability of 98.21 ± 4.32 µg/cm²/h, was gelled with 1% carbopol-940P. A 28-day anti-arthritic assessment (body weight, paw edema, and levels of pro-inflammatory mediators including TNF-α, IL-6, IL-1β, and COX-2) following topical administration of RV-NE2 gel showed significant reversal of arthritic symptoms in arthritic Wistar rats induced by Freund's complete adjuvant injection. Therefore, RV-NE2 gel demonstrated the potential to achieve local therapeutic benefits in inflammatory arthritic conditions due to its increased topical bioavailability and balancing of pro-inflammatory mediators.

Systemic Inflammation is Associated with Cardiometabolic Risk Factors and Clinical Outcomes

Purpose

Assessing an individual's systemic inflammatory state is vital to understand inflammation's role in cardiometabolic diseases and identify those at the greatest risk of disease. We generated global inflammation scores and investigated their associations with cardiometabolic risk factors and adverse outcomes.

Patients and Methods

Aggregate Inflammation Scores (AIS) and Principal Component Analysis (PCA) scores were generated for 7287 Framingham Heart Study participants using up to 26 inflammation-related proteins, with higher scores reflecting a pro-inflammatory milieu. Multivariable regression and proportional hazards analyses were conducted to investigate the associations of inflammation with cardiometabolic risk factors and outcomes. The primary outcomes for cross-sectional analyses included age, cigarette smoking, fasting lipid and glucose levels, blood pressure, body mass index (BMI), and hypertension, diabetes, and obesity. For prospective analyses, new-onset hypertension, diabetes, obesity, cardiovascular disease and all-cause mortality were investigated.

Results

Higher inflammation scores were associated with smoking and older age, higher BMI, systolic blood pressure, lipids, and glucose levels, and with greater odds of hypertension and diabetes after adjusting for age, sex, cohort, and BMI (all p < 0.001). Higher baseline scores were associated with greater odds of new-onset hypertension after adjusting for traditional risk factors (OR [95% CI] per one standard deviation [1-SD] increase, AIS: 1.33 [1.21-1.47], PCA score: 1.26 [1.12-1.42], p < 0.001). The AIS also was associated with new-onset diabetes (1.32 [1.14-1.52], p < 0.001). Proportional hazards analyses revealed greater risk of new-onset cardiovascular disease events and all-cause mortality (HR [95% CI] per 1-SD, AIS: 1.25 [1.14-1.37] and 1.32 [1.23-1.42], PCA score: 1.22 [1.13-1.33] and 1.40 [1.31-1.49], p < 0.001).

Conclusion

Global inflammation scores encompassing an array of pro- and anti-inflammatory proteins and pathways may enhance risk assessment for cardiometabolic diseases. The AIS and PCA scores provide further opportunities to investigate the mechanisms of inflammation-related risk of disease.

Effect of anti-inflammatory diets on inflammation markers in adult human populations: a systematic review of randomized controlled trials

CONTEXT

Chronic inflammation, characterized by prolonged elevated inflammation markers, is linked to several chronic conditions. Diet can influence the levels of inflammation markers in the body.

OBJECTIVE

The aim of this systematic review was to assess the effects of anti-inflammatory diets on 14 different inflammation markers in adults.

DATA SOURCES

This systematic review conducted searches using Medline, PubMed, EMCare, Cochrane, and CINAHL, to locate randomized controlled trials (RCTs).

DATA EXTRACTION

Two researchers independently screened 1537 RCTs that measured changes in inflammation markers after prescription of an intervention diet.

DATA ANALYSIS

In total, 20 RCTs were included and assessed qualitatively. The results demonstrated that a Mediterranean diet can bring about statistically significant and clinically meaningful between-group differences in interleukins -1α, -1β, -4, -5, -6, -7, -8, -10, and -18, interferon γ, tumor necrosis factor α, C-reactive protein, and high-sensitivity C-reactive protein, as compared with a control diet.

CONCLUSIONS

There may be a link between diet, inflammation markers, and disease outcomes in various adult populations. However, further research using consistent RCT protocols is required to determine correlations between diet, specific inflammation markers, and clinically relevant outcomes.

Prevalence of rheumatoid arthritis and diagnostic validity of a prediction score, in patients visiting orthropedic clinics in the Madinah region of Saudi Arabia: a retrospective cross-sectional study

Introduction

In Saudi Arabia, the epidemiology of rheumatoid arthritis (RA) is not well studied and is marked by inconsistencies in clinical diagnosis. Therefore, in this study, we explored the prevalence, clinical characteristics, and diagnostic validity of a prediction score based upon disease markers in orthropedic clinics' patients in the Madinah region of Saudi Arabia.

Method

The clinical data for this retrospective cross-sectional study were retrieved from the database registry of orthopedic clinics in selected hospitals of the Medinah province of Saudi Arabia. Sociodemographic features, disease markers and the clinical characteristics were collected for a period of 6 months, from December 1, 2020, to May 31, 2021. The prediction score was generated from the sum of disease markers, coded as dichotomous variables.

Results

The total sample size of our study was 401. The prevalence of RA in the study subjects (n = 401) was 14.46% (n = 58). Among RA patients, the majority were females (60.3%). Painful joints (69%) and swollen joints (51.7%) were the most common clinical complaints among RA patients. RA patients suffered from arthritis (51.7%) and experienced fatigue (46.6%), weight loss (44.8%), and loss of appetite (41.4%). Diabetes (55.2%) was the most common comorbidity in the RA patients. The sensitivity and specificity of the prediction score at the criterion score of 2.5 were 67.3% and 63.0%, respectively. The area under the curve was 0.69 (95% CI [0.62-0.76]).

Conclusion

There was a moderately high prevalence of RA in patients visiting the orthropedic clinics of the selected hospitals of Madinah region of Saudi Arabia. The diagnostic validity of the prediction score, though promising, was slightly lower than the acceptable range.

Fasciola hepatica extract suppresses fibroblast-like synoviocytes in vitro and alleviates experimental arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by synovial inflammation, fibroblast-like synoviocytes (FLS) activation and joint destruction. Fasciola hepatica is a platyhelminth that releases excretory-secretory immunomodulatory products capable of suppressing the Th1 immune response. Despite the effectiveness of available treatments for inducing disease remission, current options are not successful in all patients and may cause side effects. Thus, we evaluated the therapeutic potential of F. hepatica extract on FLS from RA patients and arthritis models.

METHODS

FLS were isolated from synovial fluid of RA patients, cultured, and exposed to F. hepatica extract (60, 80, and 100 µg/ml) for different time points to assess cell viability, adherence, migration and invasion. For in vivo experiments, mice with antigen (AIA) and collagen (CIA) induced arthritis received a 200 µg/dose of F. hepatica extract daily. Statistical analysis was performed by ANOVA and Student's t-test using GraphPad Prism 6.0.

RESULTS

In vitro assays showed that extract decreased FLS cell viability at concentration of 100 µg/ml (83.8% ± 5.0 extract vs. 100.0% ± 0.0 control; p < 0.05), adherence in 20% (92.0 cells ± 5.8 extract vs. 116.3 cells ± 7.9 control; p < 0.05), migratory potential (69.5% ± 17.6 extract vs. 100.0% control; p < 0.05), and cell invasiveness potential through the matrigel (76.0% ± 8.4 extract vs. 100.0% control; p < 0.01). The extract reduced leukocyte migration by 56% (40 × 10⁴ leukocytes/knee ± 19.00) compared to control (90.90 × 10⁴ leukocytes/knee ± 12.90) (p < 0.01) and nociception (6.37 g ± 0.99 extract vs. 3.81 g ± 1.44 control; p < 0.001) in AIA and delayed clinical onset of CIA (11.75 ± 2.96 extract vs. 14.00 ± 2.56 control; p = 0.126).

CONCLUSION

Our results point out a potential immunomodulatory effect of F. hepatica extract in RA models. Therefore, the characterization of promising new immunomodulatory molecules should be pursued, as they can promote the development of new therapies. Trial registration Collection of synovial liquid and in vitro procedures were approved by the Ethics Committee with Certificate of Presentation of Ethical Appreciation in Plataforma Brasil (CAAE: 89044918.8.0000.5327; date of registration: 26/07/2018).

Deer Velvet Antler Extracts Exert Anti-Inflammatory and Anti-Arthritic Effects on Human Rheumatoid Arthritis Fibroblast-Like Synoviocytes and Distinct Mouse Arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease that causes joint deformity and disability. Deer velvet antler (DA), a traditional Chinese medicine, has been used to treat various types of arthritis for several thousands of years, but the underlying mechanisms are unknown. Herein, we investigated the anti-arthritic and anti-inflammatory effects of DA in vitro and in vivo. The ethyl acetate layer of DA ethanol extract (DA-EE-EA) was used to treat tumor necrosis factor (TNF)-[Formula: see text]-stimulated fibroblast-like synoviocyte MH7A cells, collagen-induced arthritis DBA/1 mice, and SKG mice with zymosan-induced arthritis. DA-EE-EA reduced nitric oxide production, prostaglandin E2 levels, and levels of pro-inflammatory cytokines including interleukin (IL)-1[Formula: see text], IL-6, and IL-8 in MH7A cells. DA-EE-EA also downregulated the phosphorylation of mitogen-activated protein kinase p38 and c-Jun N-terminal kinase and the translocation of nuclear factor kappa B p65. Intraperitoneal injection of DA-EE-EA for 3 weeks substantially reduced clinical arthritis scores in vivo models. Pathohistological images of the hind paws showed that DA-EE-EA reduced immune cell infiltration, synovial hyperplasia, and cartilage damage. The levels of pro-inflammatory cytokines, such as tumor necrosis factor alpha, IL-1[Formula: see text], IL-6, IL-8, IL-17A, and interferon-gamma, decreased in the hind paw homogenates of DA-EE-EA-treated mice. We also identified several potential components, such as hexadecanamide, oleamide, erucamide, and lysophosphatidylcholines, that might contribute to the anti-inflammatory effects of DA-EE-EA. In conclusion, DA-EE-EA has the potential to treat RA by regulating inflammatory responses. However, the individual components of DA-EE-EA and the underlying anti-inflammatory mechanisms need further investigation in future studies.

Assessment of IL-1β, IL-6, TNF-α, IL-8, and CCL 5 levels in newly diagnosed Saudi patients with rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disorder which mainly affects small joints, occurs most commonly in middle-aged adults, and can be fatal in severe cases. The exact etiology of RA remains unknown. However, uncontrolled expression of pro-inflammatory cytokines and chemokines can contribute to the pathogenesis of RA.

AIM

In the current study, we assessed the potential of serum concentrations of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, IL-8, and C-C motif chemokine ligand (CCL)5 as early predictive markers for RA.

METHODS

In addition to clinical examination, blood samples were collected from 100 Saudi patients recently diagnosed with early RA for basic and serological tests, including rheumatoid factor (RF), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). Sera of 32 healthy individuals were used as controls. Specific enzyme-linked immunosorbent assay was used to quantify the serum IL-1β, IL-6, TNF-α, IL-8, and CCL5 levels in the samples.

RESULTS

Our results indicated that RF, CRP, and ESR levels were higher in RA patients compared to controls. Furthermore, serum levels of IL-1β, IL-6, IL-8, and CCL5, but not TNF-α, significantly increased in RA patients compared to controls.

CONCLUSION

Overall, the findings suggested that IL-1β, IL-6, IL-8, and CCL5 can be used as biomarkers in the early diagnosis of RA.

Clonal hematopoiesis: Mutation-specific adaptation to environmental change

Clonal hematopoiesis of indeterminate potential (CHIP) describes a widespread expansion of genetically variant hematopoietic cells that increases exponentially with age and is associated with increased risks of cancers, cardiovascular disease, and other maladies. Here, we discuss how environmental contexts associated with CHIP, such as old age, infections, chemotherapy, or cigarette smoking, alter tissue microenvironments to facilitate the selection and expansion of specific CHIP mutant clones. Further, we consider major remaining gaps in knowledge, including intrinsic effects, clone size thresholds, and factors affecting clonal competition, that will determine future application of this field in transplant and preventive medicine.

RelA/MicroRNA-30a/NLRP3 signal axis is involved in rheumatoid arthritis via regulating NLRP3 inflammasome in macrophages

NLRP3 inflammasome plays an important role in the pathogenesis of rheumatoid arthritis (RA). However, the post-transcriptional regulation of NLRP3 expression by miRNA in synovial macrophages is still not well understood. The aim of the study is to elucidate the mechanisms of RA with the focus on miRNAs mediated post-transcriptional regulation of the NLRP3 inflammasome. Here, we used NLRP3-deficient mice (NLRP3^KO) to cross with TNFα-transgenic mice (TNF^TG) to generate NLRP3^KO/TNF^TG mice, and compared their joint phenotypes with those of their TNF^TG and wild-type (WT) littermates at 5 months of age. In comparison to WT mice, articular bone volume and cartilage area are decreased, whereas inflammed area, eroded surface, ALP+ osteoblast number, TRAP+ osteoclast number, and the areas of RelA+F4/80+, Caspase-1+F4/80+, IL-1β+F4/80+ synoviocytes are increased in the TNF^TG mice. Knockout of NLRP3 ameliorates joint inflammation and bone damage in TNF^TG mice. Further, in TNFα-primed BMDMs, RelA positively regulates NLRP3 expression, but negatively regulates miR-30a. Additionally, miR-30a negatively mediates NLRP3 expression by directly binding to its 3' UTR, suggesting a miR-30a-mediated feedforward loop acting on NLRP3. Finally, intra-articular injection of AAV-miR-30a inhibits NLRP3 inflammasome activation, reduces joint inflammation, and attenuates bone damage in TNF^TG mice. Thus, RelA/miR-30a/NLRP3 signal axis is involved in RA through regulating NLRP3 Inflammasome in macrophages.

Gain of CXCR7 function with mesenchymal stem cell therapy ameliorates experimental arthritis via enhancing tissue regeneration and immunomodulation

BACKGROUND

The major barriers to mesenchymal stem cell (MSC) therapy in rheumatoid arthritis (RA) are a low extent of tissue regeneration and insufficient immunomodulation after cell transplantation. In addition, the role of C-X-C chemokine receptor type 7 (CXCR7) and its mechanism of action in MSC-mediated osteogenic or chondrogenic differentiation and immunomodulation are unclear.

METHODS

Gain of CXCR7 function on human MSCs was carried out by lentiviral vector-mediated CXCR7 overexpression or CXCR7 agonist, TC14012. These cells were determined the role and potential mechanisms for CXCR7-regulated MSC differentiation and immunomodulation using cellular and molecular assays. The therapeutic benefits in RA were investigated in rats with collagen-induced arthritis (CIA).

RESULTS

CXCR7 was upregulated in MSCs during the induction of osteogenic or chondrogenic differentiation. Blockage of CXCR7 function inhibited osteogenic or chondrogenic differentiation of MSCs whereas gain of CXCR7 function had the opposite effects. Besides, MSCs with CXCR7 gain-of-function facilitated macrophage apoptosis and regulatory T cell differentiation in a co-culture system. Gain of CXCR7 function also promoted the production of anti-inflammatory soluble factors. A gene expression profiling assay and signaling reporter assays revealed that CXCR7 could regulate several candidate genes related to the PPAR, WNT, Hedgehog or Notch pathways, and their signaling activities, which are known to control cell differentiation and immunomodulation. Finally, MSCs with CXCR7 gain-of-function significantly reduced the articular index scores, ankle circumference, radiographic scores, histologic scores, and inflammation in rats with CIA compared with control MSCs.

CONCLUSIONS

CXCR7 promotes the osteogenic and chondrogenic differentiation of MSCs and MSC-mediated immunomodulation by regulating several signaling pathways and anti-inflammatory soluble factors. MSCs with CXCR7 gain-of-function significantly ameliorate arthritic symptoms in a CIA model.

Location, location, location: how the tissue microenvironment affects inflammation in RA

Current treatments for rheumatoid arthritis (RA) do not work well for a large proportion of patients, or at all in some individuals, and cannot cure or prevent this disease. One major obstacle to developing better drugs is a lack of complete understanding of how inflammatory joint disease arises and progresses. Emerging evidence indicates an important role for the tissue microenvironment in the pathogenesis of RA. Each tissue is made up of cells surrounded and supported by a unique extracellular matrix (ECM). These complex molecular networks define tissue architecture and provide environmental signals that programme site-specific cell behaviour. In the synovium, a main site of disease activity in RA, positional and disease stage-specific cellular diversity exist. Improved understanding of the architecture of the synovium from gross anatomy to the single-cell level, in parallel with evidence demonstrating how the synovial ECM is vital for synovial homeostasis and how dysregulated signals from the ECM promote chronic inflammation and tissue destruction in the RA joint, has opened up new ways of thinking about the pathogenesis of RA. These new ideas provide novel therapeutic approaches for patients with difficult-to-treat disease and could also be used in disease prevention.

BT2 Suppresses Human Monocytic-Endothelial Cell Adhesion, Bone Erosion and Inflammation

Introduction

Inflammation and bone erosion are processes key to the pathogenesis of rheumatoid arthritis, a systemic autoimmune disease causing progressive disability and pain, impacting around 1.3 million people in the United States alone. However, many patients do not respond sufficiently to existing therapies or benefit is not sustained and alternate therapeutic approaches are lacking. We recently identified the dibenzoxazepinone BT2, which inhibits ERK phosphorylation, from a high-throughput chemical screen and identified its ability to inhibit angiogenesis and vascular leakiness.

Methods

Here we evaluated BT2 for potential anti-inflammatory activity in in vitro models of human monocytic-endothelial cell adhesion, monocytic cell extravasation and collagen antibody-induced arthritis in mice.

Results

BT2 inhibits human monocytic cell adhesion to IL-1ß-treated human endothelial cells and inhibits monocytic transendothelial migration toward MCP-1. In mice rendered arthritic, single systemic administration of BT2 prevented footpad swelling, bone destruction and TRAP⁺ cells in the joints. BT2 suppressed inducible circulating levels of IL-1ß, IL-2 and IL-6 to normal levels without affecting levels of IL-4 or IL-10 among other cytokines. BT2 also inhibited the expression of pro-inflammatory adhesion molecules ICAM-1 and VCAM-1 in arthritic joints. There was no evidence of toxicity following intraperitoneal, gavage or intraarticular administration of BT2.

Conclusion

BT2 is a novel small molecule inhibitor of joint inflammation, bone erosion, pro-inflammatory cytokine and adhesion molecule expression. This suggests the potential clinical utility of BT2 as a new anti-inflammatory agent.

Polyherbal formula SC-E3 inhibits rheumatoid arthritis activity in a mouse model of type-II collagen-induced arthritis

OBJECTIVE

SC-E3 is a polyherbal formula that contains five medicinal herbs used frequently in traditional herbal medicine. In our previous study, we demonstrated the antioxidant and anti-inflammatory effects of SC-E3. The present study examined the effects of SC-E3 in a mouse model of type-II collagen-induced arthritis (CIA).

METHODS

In vivo, male DBA/1J mice were immunized by intradermal injection of bovine type-II collagen and complete or incomplete Freund's adjuvant, to induce arthritis. SC-E3 was orally administered daily for 23 days. In vitro, bone marrow-derived macrophages (BMMs) were treated with macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL) in the absence or presence of SC-E3.

RESULTS

Administrations of SC-E3 were found to have anti-arthritic effects in the joints of CIA mice, as evidenced by reduced paw swelling, bone erosion and deformation, inflammatory cell infiltration, and inflammation in synovial membrane. SC-E3 also reduced serum levels of tumor necrosis factor-α, interleukin-1β, aspartate aminotransferase and alanine aminotransferase. Furthermore, tartrate-resistant acid phosphatase-positive osteoclast numbers in the joints were significantly lower in SC-E3-treated CIA mice than in CIA mice. In addition, the differentiations of BMMs to multinucleated osteoclasts induced by M-CSF and RANKL stimulation were dose-dependently reduced by SC-E3.

CONCLUSION

These results suggest that SC-E3 possesses substantial anti-arthritic activity because it inhibits pro-inflammatory cytokines and osteoclastogenesis, and that SC-E3 has potential therapeutic use for the treatment of rheumatoid arthritis.

Aqueous Extract of Kan-Lu-Hsiao-Tu-Tan Ameliorates Collagen-Induced Arthritis in Mice by Inhibiting Oxidative Stress and Inflammatory Responses

Background: Kan-Lu-Hsiao-Tu-Tan (KLHTT) exhibits anti-psoriatic effects through anti-inflammatory activity in mice. However, the therapeutic effects of KLHTT on rheumatoid arthritis (RA), another significant autoimmune inflammatory disorder, have not been elucidated. Herein, we explored the anti-arthritic effects of KLHTT on collagen-induced arthritis (CIA) in mice. Methods: KLHTT was extracted by boiling water and subjected to spectroscopic analysis. Chicken collagen type II (CII) with complete Freund’s adjuvant was intradermally injected to induce CIA in DBA/1J mice. Anti-CII antibody, cytokines, malondialdehyde (MDA), and hydrogen peroxide (H₂O₂) were measured using ELISA, thiobarbituric acid reactive substances, and a hydrogen peroxide assay kit. Splenocyte proliferation was tested using thymidine incorporation. Th1 and Th17 cells were analyzed by flow cytometry. Results: Oral KLHTT treatment (50 and 100 mg/kg) ameliorated mouse CIA by decreasing the levels of interleukin (IL)-1β, IL-6, IL-17A, and tumour necrosis factor-α in the paw homogenates and serum. KLHTT also suppressed anti-CII antibody formation, splenocyte proliferation, and splenic Th1 and Th17 cell numbers. Additionally, KLHTT showed antioxidant activity by reducing the concentrations of MDA and H₂O₂ in paw tissues. Conclusions: The therapeutic effects of KLHTT in CIA mice were through regulating oxidative stress and inflammatory responses. Our results suggest that KLHTT has potential to treat RA.

Effect of walnut (Juglans sigillata) oil on intestinal antioxidant, anti-inflammatory, immunity, and gut microbiota modulation in mice

The study investigated the anti-oxidant, anti-inflammatory, immunity, and gut microbiota modulation in mice (n = 60; 15 mice/group) after intragastric administration of walnut oil (WO; three groups (low (LD), medium (MD), and high doses (HD): 2.5, 5, and 10 ml/kg, respectively) and normal control (NC, saline). WO significantly increased the median villous height/crypt depth (VH/CD) ratio, the activities of superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) in intestinal mucosa. WO exerted the anti-inflammatory effects by decreasing the expression of tumor necrosis factor-α (TNF-α) in the duodenal mucosa. All groups shared 157 operational taxonomic units (OTUs; 97% similarity) representing nine phyla. The relative abundance in gut microbiota shifted from more pathogenic bacteria-Helicobacter (NC: 22% versus MD: 3%) toward probiotic-Lactobacillus (NC: 19% versus MD: 40%). The immune organ index (spleen) and contents of secretory immunoglobulin A (S-IgA) were increased from small intestine. In conclusion, WO decreased the oxidative stress, inflammation, and improved the immunity and beneficial gut microbiota in the mice. PRACTICAL APPLICATIONS: Walnut oil (WO) is widely used in traditional medicine around the world and is prescribed as beneficial food oil in agro-industry. However, the intestinal benefits of WO have not been explored extensively, and even its therapeutic mechanism still remains unknown in modern medicine. In this study, WO from Juglans sigillata was investigated for its preventive and protective effects on the intestinal mucosa in mice including anti-oxidant, anti-inflammatory, immunity, and gut microbiota modulation. WO decreased the oxidative stress, inflammation, and improved immunity and beneficial gut microbiota in the mice. WO has shown strong probiotic effect on the gut, and thus, can be considered as a potential candidate in food. The study outcome would enhance utilization of WO for the prevention of gastrointestinal diseases (e.g., Helicobacter, etc.) both in animals and human (inflammatory bowel diseases, IBD) and the formulation of functional foods.

Andrographolide attenuates complete freund's adjuvant induced arthritis via suppression of inflammatory mediators and pro-inflammatory cytokines

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional plant-derived medicines have enabled the mankind in curing the wide spectrum of diseases throughout the ages. Andrographis paniculata (Burm.f.) Nees, is one of the traditional plant used as a folk medicine for the management of inflammation, arthritis, viral-bacterial infections and other ailments in India, China, Malaysia and other South-East Asian countries. Its major bioactive compound; andrographolide, a diterpenoid, also exerts cytoprotective properties and is reported to be effective in neuroprotection, hepatoprotection, etc. AIM: The study is aimed to explore the role of andrographolide in treatment of complete freund's adjuvant (CFA) induced arthritis.

MATERIALS AND METHODS

The influx of immune cells, release of pro-inflammatory cytokines and subsequent accumulation of synovial fluid (swelling) and pain manifest into the disease. The present study used CFA induced Balb/c mice model and treated them intraperitoneally with andrographolide and dexamethasone (used as a positive control) on alternate days for six days. After 6 days, blood and peritoneal macrophages were collected to evaluate the expression of various arthritic markers and paw edema was measured on all days.

RESULTS

The in vitro and ex vivo experiments showed that andrographolide treated animal group had reduced paw edema, cell cytotoxicity and nitric oxide production than dexamethasone treated animal group. Further, the study revealed the mechanistic role of andrographolide in treatment of arthritis by suppressing battery of molecules like COX-2, NF-κB, p-p38, CD40, TNF-α, IL-1β and IL-6 involved in arthritis.

CONCLUSION

The study showed the potent anti-arthritic effects of andrographolide and warrants further investigations on andrographolide for the development of safe and effective anti-arthritic drug.

The recombinant anti-TNF-α fusion protein ameliorates rheumatoid arthritis by the protective role of autophagy

The currently used anti-cytokine therapeutic antibodies cannot selectively neutralize pathogenic cytokine signaling that cause collateral damage to protective signaling cascades carrying the potential for unwanted side effects. The variable domains of heavy-chain only antibodies (HCAbs) discovered in Camelidae are stable and display to be fully functional in antigen-binding against variable targets, which seem to be attractive candidates for the next-generation biologic drug study. The purpose of our study was to establish a simple prokaryotic expression system for large-scale expression, purification, and refolding of the recombinant anti-tumor necrosis factor α (TNF-α) fusion protein (FVH1-1) from inclusion bodies. Over 95% purity of the recombinant anti-TNF-α fusion proteins was obtained by just one purification step in our developed prokaryotic expression system, while the results of surface plasmon resonance (SPR) established the high-efficiency potent binding ability of FVH1-1 to human TNF-α. The counteraction of TNF-α cytotoxic effect experiment on the mouse fibroblast fibrosarcoma cell line (L929) confirmed that the expressed FVH1-1 were able to selectively and highly combine with human recombinant TNF-α (hTNF-α) in vitro. Western blot results showed that FVH1-1 can inhibit the activation of caspase-9 and PARP, which are the apoptotic signaling pathway proteins activated by hTNF-α. Meanwhile, lysosome autophagy signaling pathways stimulated by hTNF-α were inhibited by FVH1-1, which down-regulated the expression of LC3II/LC3I and up-regulated the expression of P62, indicating that the autophagy linked with TNF-α-induced apoptosis in response to rheumatoid arthritis. The results of the AIA rat model experiment presented that FVH1-1 can reduce the degree of joint swelling and inflammatory factors to a certain extent in vivo.

Therapeutic Effect of Carvacrol-loaded Albumin Nanoparticles on Arthritic Rats

Rheumatoid arthritis (RA) is one of the most common autoimmune diseases. Carvacrol, an important natural terpenoid product in aromatic plants such as thyme, has shown anti-inflammatory effects in animal models of arthritis. However, its poor water solubility and high volatility have limited its application. In the present study in order to overcome this problem, we encapsulated carvacrol in the bovine serum albumin (BSA) nanoparticles and examined its therapeutic and immunomodulatory effects in adjuvant-induced arthritis (AIA). Carvacrol-loaded BSA nanoparticles were prepared by desolvation method. Nanoparticles had encapsulation efficiency (EE) of 67.7 ± 6.9% and loading capacity (LC) of 26.6 ± 2%. The size of particles was 148 ± 25 nm and they had monomodal distribution. After arthritis induction, the rats were treated intraperitoneally with nanoparticle for every 3 days until day 28. The treatment of the rats with 375 mg/mL carvacrol-loaded BSA nanoparticle significantly decreased clinical severity score (27.5 ± 9.8%, p = 0.008), erythrocyte sedimentation rate (33.4 ± 10%, p = 0.02), nitric oxide production (82.3 ± 2.6%, p = 0.004) and interleukin (IL)-17 gene expression (55.1 ± 8.2%, p = 0.003) compared to the untreated arthritic group. A higher reduction in inflammation severity in arthritic rats treated with carvacrol-loaded BSA in comparison to those treated with carvacrol alone was observed. In conclusion, encapsulation of carvacrol in nanoparticles reduced arthritis signs and release of NO and IL-17 inflammatory cytokine and therefore is suggested to be considered as a good approach for improving the therapeutic applications of carvacrol in RA.

Evaluation of rohitukine-enriched fraction of Dysoxylum binectariferum Hook.f. (leaves) as anti-arthritic phytopharmaceutical candidate: Chemical standardization, in-vivo validation, formulation development and oral pharmacokinetics

ETHNOPHARMACOLOGICAL RELEVANCE

Rheumatoid arthritis is a chronic inflammatory disease of joints. Dysoxylum binectariferum Hook.f (Family: Meliaceae) is a Indian medicinal plant which is traditionally being used to heal inflammation of joints.

AIM OF THE STUDY

This work was aimed to carry out chemical standardization, in-vitro/in-vivo validation, oral pharmacokinetics and formulation development of anti-arthritic botanical lead, the rohitukine-enriched fraction of D. binectariferum.

MATERIALS AND METHODS

The rohitukine-enriched fraction of D. binectariferum was standardized using four chemical markers and was checked for microbial load, heavy metal content, aflatoxins and pesticides. Its in-vitro inhibitory effect on the lipopolysaccharide (LPS) induced production of pro-inflammatory cytokines TNF-α and IL-6 was studied in THP-1 cells. The in-vivo anti-arthritic activity was investigated in collagen-induced arthritis model in DBA/1J mice. The sustained release capsule formulation was developed and characterized for physicochemical and pharmacokinetic properties.

RESULTS

Rohitukine and schumaniofioside A were found to be major chemical constituents of the botanical lead. The rohitukine-enriched fraction of D. binectariferum significantly reduced the production of both pro-inflammatory cytokines TNF-α and IL-6 (>50% inhibition at 3.12 μg/mL) in THP-1 cells. In LPS-treated wild-type mice model, the rohitukine-enriched fraction at 200 mg/kg (PO, QD) completely reduced serum TNF-α levels. In transgenic mice model (collagen-induced arthritis in DBA/1J mice), rohitukine-enriched fraction at 100 mg/kg (PO, QD) dose has resulted in >75% reduction of TNF-α/IL-6 serum levels, 68% reduction in anti-mouse type II collagen IgG1 antibody levels, decreased joint proteoglycan loss and reduced paw edema in DBA/1J mice. The sustained release capsule formulation of rohitukine-enriched fraction showed sustained-release of rohitukine over the period of 24 h, and resulted in an improved plasma-exposure of rohitukine in SD rats.

CONCLUSIONS

The data presented herein demonstrated anti-arthritic potential of rohitukine-enriched fraction of D. binectariferum and this study will serve as the benchmark for further research on this botanical lead and developed sustained release capsule formulation.

Metformin rescues rapamycin-induced mitochondrial dysfunction and attenuates rheumatoid arthritis with metabolic syndrome

Background

Rapamycin, an inhibitor of the serine/threonine protein kinase mTOR, is an immunosuppressant used to treat renal transplant recipients, but it can cause endothelial and mitochondrial dysfunction. Metformin is used for the treatment of type 2 diabetes and was reported to exert therapeutic effects against rheumatoid arthritis and obesity by improving mitochondrial dysfunction via the activation of fibroblast growth factor 21. We investigated the therapeutic effects of rapamycin–metformin combination therapy in obese mice with collagen-induced arthritis (CIA).

Methods

Mouse embryonic fibroblasts were treated with rapamycin, metformin, or rapamycin–metformin, and their respiratory level and mitochondrial gene expression were assayed. Mice were fed a high-fat diet, immunized with type II collagen, and subsequently treated with rapamycin–metformin daily for 10 weeks.

Results

Rapamycin-treated cells exhibited dysfunction of mitochondrial respiration and decreased mitochondrial gene expression compared with rapamycin–metformin-treated cells. Moreover, rapamycin–metformin reduced the clinical arthritis score and the extent of histological inflammation and improved the metabolic profile in obese mice with CIA. Rapamycin–metformin enhanced the balance between T helper 17 and regulatory T cells in vitro and in vivo.

Conclusions

These results suggest that rapamycin–metformin is a potential therapeutic option for autoimmune arthritis.

A Pilot Study to Evaluate the Effects of Oral N-Acetyl Cysteine on Inflammatory and Oxidative Stress Biomarkers in Rheumatoid Arthritis

BACKGROUND

Rheumatoid Arthritis (RA) is a common inflammatory disease of the joints. Due to the importance of inflammation and oxidative stress in the pathogenesis of RA, drugs that have anti-oxidant and anti-inflammatory properties, such as N-acetyl Cysteine (NAC), can be used as adjunctive therapy in patients with RA.

AIMS

The aim of this study was to evaluate the effects of oral NAC on inflammatory cytokines and oxidative stress in patients with RA.

METHODS

Adjunct to standard treatment, the NAC group (23 patients) received 600 mg of NAC twice daily and the placebo group (19 patients) received identical placebo twice daily for 12 weeks. Serum levels of Total Oxidant Status (TOS), Total Antioxidant Capacity (TAC), nitric oxide (NO), Total Thiol Groups (TTG), Malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), interleukin- 6 (IL-6), C-reactive Protein (CRP), and Erythrocyte Sedimentation Rate (ESR) were measured at baseline and at the end of the study.

RESULTS

Results showed that in the NAC group, the serum levels of MDA, NO, IL-6, TNF-α, ESR and CRP were significantly lower than the baseline. Also, the serum level of TAC and TTG, as antioxidant parameters, increased significantly. However, only NO, MDA and TTG showed a significant difference in the NAC group as compared to the placebo group at the end of study.

CONCLUSION

According to the results of this study, oral NAC can significantly reduce the several oxidative stress factors and inflammatory cytokines. These results need to be confirmed in larger studies while considering clinical outcomes of RA patients.

Perturbation Theory Machine Learning Modeling of Immunotoxicity for Drugs Targeting Inflammatory Cytokines and Study of the Antimicrobial G1 Using Cytometric Bead Arrays

ChEMBL biological activities prediction for 1-5-bromofur-2-il-2-bromo-2-nitroethene (G1) is a difficult task for cytokine immunotoxicity. The current study presents experimental results for G1 interaction with mouse Th1/Th2 and pro-inflammatory cytokines using a cytometry bead array (CBA). In the in vitro test of CBA, the results show no significant differences between the mean values of the Th1/Th2 cytokines for the samples treated with G1 with respect to the negative control, but there are moderate differences for cytokine values between different periods (24/48 h). The experiments show no significant differences between the mean values of the pro-inflammatory cytokines for the samples treated with G1, regarding the negative control, except for the values of tumor necrosis factor (TNF) and Interleukin (IL6) between the group treated with G1 and the negative control at 48 h. Differences occur for these cytokines in the periods (24/48 h). The study confirmed that the antimicrobial G1 did not alter the Th1/Th2 cytokines concentration in vitro in different periods, but it can alter TNF and IL6. G1 promotes free radicals production and activates damage processes in macrophages culture. In order to predict all ChEMBL activities for drugs in other experimental conditions, a ChEMBL data set was constructed using 25 biological activities, 1366 assays, 2 assay types, 4 assay organisms, 2 organisms, and 12 cytokine targets. Molecular descriptors calculated with Rcpi and 15 machine learning methods were used to find the best model able to predict if a drug could be active or not against a specific cytokine, in specific experimental conditions. The best model is based on 120 selected molecular descriptors and a deep neural network with area under the curve of the receiver operating characteristic of 0.904 and accuracy of 0.832. This model predicted 1384 G1 biological activities against cytokines in all ChEMBL data set experimental conditions.

Anti-Inflammatory and Anti-Arthritic Efficacies of an Indian Traditional Herbo-Mineral Medicine "Divya Amvatari Ras" in Collagen Antibody-Induced Arthritis (CAIA) Mouse Model Through Modulation of IL-6/IL-1β/TNF-α/NFκB Signaling

Rheumatoid arthritis (RA) is defined as a chronic autoimmune inflammatory disorder that causes damage to limb joints and progressive injuries to secondary organs. Medical practitioners prescribe Methotrexate (MTX) as standard care medicine for treating RA. However, the long-term application of MTX has shown to have adverse health-related effects. Divya Amvatari Ras (DAR), an Indian Ayurvedic herbo-mineral formulation, has been described in ancient texts to provide relief from RA inflammation associated distress. Therefore, in the present study, we explored the biocompatibility, anti-inflammatory, and anti-arthritic efficacy of DAR using in vivo and in vitro disease models. Using carrageenan (CA)-stimulated Wistar rat paw edema model, we showed a reduction in inflammation-induced paw edema at human equivalent dose of DAR. Anti-rheumatic efficacy of DAR was studied using collagen-antibody cocktail (C-Ab) Induced Arthritis (CAIA) mouse model. The onset of RA in the CAIA mice was determined using parameters such as the increase in arthritis score, and induction of disease associated lesions in the ankle and knee joints, and increase in mechanical and thermal hyperalgesia. Treatment of CAIA animals with a human equivalent dose of DAR significantly reversed the RA-associated pathogenesis. These effects were comparable with the standard of care RA drug, MTX. DAR acted at multiple levels of inflammation associated with RA to reduce progressive pathogenesis. Animal serum biochemistry showed DAR was capable of ameliorating RA induced increase in liver enzyme Alanine Aminotransferase (ALT) and pro-inflammatory cytokine interleukin 6 (IL-6). In the lipopolysaccharide stimulated THP-1 cells, DAR was found to inhibit the release of IL-6, IL-1β, TNF-α, and upstream inflammatory gene regulatory protein, NFκB. The study endorsed the anti-arthritic and anti-inflammatory activity of the Indian Traditional herbo-mineral medicine, DAR. These results also confirm that DAR was highly biocompatible and would show minimal health-related side effects than those associated with standard of care MTX. Taken together, we show that the DAR could be utilized as a promising alternative or complementary therapy for treating rheumatoid arthritis.

Lactobacillus fermentum PC1 has the Capacity to Attenuate Joint Inflammation in Collagen-Induced Arthritis in DBA/1 Mice

Lactobacillus strains have shown efficacy in attenuating inflammation. This study evaluated the potential of Lactobacillus fermentum PC1 for the treatment of rheumatoid arthritis (RA) using a murine model of collagen-induced arthritis. On Day 1, healthy DBA/1 mice (six to eight weeks of age) were immunized, with 100 μg of Chicken Type 11 collagen emulsified in complete Freund’s adjuvant (CFA) by intradermal injection, at the base of the tail. On Day 21, the mice were immunized intraperitoneally with 100 μg of Bovine Type11 collagen in phosphate buffered saline (PBS). On Day 28, the mice were immunized intraperitoneally with 50 μg of lipopolysaccharide (LPS). Viable L. fermentum PC1 (1 × 10⁹ colony forming units) was given daily from Day two until the end of the experiment. From Day 21 onwards, the mice were monitored daily for clinical signs of arthritis. On Day 44, the experiment was terminated. Paws were obtained for histology and serum for cytokine assays. L. fermentum PC1-fed mice had significantly reduced paw inflammation as well as decreased synovial infiltration and less cartilage damage. Circulating serum cytokine profiles revealed decreased IL-12 and increased anti-inflammatory cytokines, namely IL-4 and IL-10. Thus, early administration of L.fermentum PC1 could prove to be a valuable therapeutic agent in the management of RA.

Targeting Mesenchymal Stromal Cells/Pericytes (MSCs) With Pulsed Electromagnetic Field (PEMF) Has the Potential to Treat Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic inflammation of synovium (synovitis), with inflammatory/immune cells and resident fibroblast-like synoviocytes (FLS) acting as major players in the pathogenesis of this disease. The resulting inflammatory response poses considerable risks as loss of bone and cartilage progresses, destroying the joint surface, causing joint damage, joint failure, articular dysfunction, and pre-mature death if left untreated. At the cellular level, early changes in RA synovium include inflammatory cell infiltration, synovial hyperplasia, and stimulation of angiogenesis to the site of injury. Different angiogenic factors promote this disease, making the role of anti-angiogenic therapy a focus of RA treatment. To control angiogenesis, mesenchymal stromal cells/pericytes (MSCs) in synovial tissue play a vital role in tissue repair. While recent evidence reports that MSCs found in joint tissues can differentiate to repair damaged tissue, this repair function can be repressed by the inflammatory milieu. Extremely-low frequency pulsed electromagnetic field (PEMF), a biophysical form of stimulation, has an anti-inflammatory effect by causing differentiation of MSCs. PEMF has also been reported to increase the functional activity of MSCs to improve differentiation to chondrocytes and osteocytes. Moreover, PEMF has been demonstrated to accelerate cell differentiation, increase deposition of collagen, and potentially return vascular dysfunction back to homeostasis. The aim of this report is to review the effects of PEMF on MSC modulation of cytokines, growth factors, and angiogenesis, and describe its effect on MSC regeneration of synovial tissue to further understand its potential role in the treatment of RA.

Betulinic acid inhibits cell proliferation, migration, and inflammatory response in rheumatoid arthritis fibroblast-like synoviocytes

Betulinic acid (BA), a pentacyclic triterpene derived from the bark of the white birch tree, has been reported to have a variety of pharmacological effects, including antioxidant, anti-inflammatory, antitumor, immunomodulatory, and antiarthritis properties. However, the role of BA in rheumatoid arthritis (RA) remains unclear. Thus, the objective of this study was to examine the effects of BA on RA fibroblast-like synoviocytes (RA-FLS) proliferation, migration, and inflammatory response, and further explore the potential underlying mechanisms. Our results showed that BA inhibited the proliferation, migration, and invasion of RA-FLSs. BA also attenuated tumor necrosis factor-α (TNF-α), enhanced matrix metalloproteinases (MMPs) expression, and inflammatory cytokines production in RA-FLS. Furthermore, BA prevented the activation of Akt/NF-κB pathway in RA-FLS exposed to TNF-α. In conclusion, these findings indicated that BA inhibits cell proliferation, migration, and inflammatory response in RA-FLS; and the Akt/NF-κB signaling pathway was involved in the protective effect of BA on RA-FLS. Thus, BA might be a potential therapeutic agent for the treatment of RA.

Comparison of the anti-inflammatory effects of Sinapis alba and Brassica juncea in mouse models of inflammation

BACKGROUND

Sinapis Semen is derived from the dried mature seeds of Sinapis alba L. or Brassica juncea (L.) Czern. et Coss. Traditionally, the seeds from S. alba are called "White Sinapis Semen" while those from B. juncea are called "Yellow Sinapis Semen".

PURPOSE

The present study aimed to compare the chemical composition and the anti-inflammatory effects of 50% aqueous ethanol extracts of the White Sinapis Semen (EWSS) and Yellow Sinapis Semen (EYSS) using both acute (12-O-tetradecanoylphorbol-acetate (TPA)- and arachidonic acid (AA)-induced mouse ear edema) and chronic (multiple applications of croton oil (CO)) inflammatory models.

METHODS

The anti-inflammatory effects of EWSS and EYSS were determined by measuring the ear thickness and myeloperoxidase (MPO) activity. The anti-inflammatory mechanism was explored by measuring the protein and mRNA levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 in the ear of the TPA-treated mice.

RESULTS

The results showed that both EWSS and EYSS significantly decreased the ear thickness in both the TPA- and AA-induced acute models, as well as in the CO-induced chronic model. In addition, EWSS and EYSS could markedly inhibit the MPO activity in the ears of TPA-, AA- or CO-treated mice. Moreover, EWSS and EYSS also remarkably inhibited the protein and mRNA levels of TNF-α and IL-6 in the ears of TPA-treated mice. Comparatively, EWSS exerted more potent anti-inflammatory effect than that of EYSS.

CONCLUSION

Our results revealed that both EWSS and EYSS are effective anti-inflammatory agents against acute and chronic inflammatory processes, and EWSS possess more potent anti-inflammatory effect than EYSS. The anti-inflammatory effect of the two herbs may be mediated, at least in part, by suppressing the mRNA expression of a panel of inflammatory mediators including TNF-α, IL-6 and IL-1β.

The competitive nature of signal transducer and activator of transcription complex formation drives phenotype switching of T cells

Signal transducers and activators of transcription (STATs) are key molecular determinants of T-cell fate and effector function. Several inflammatory diseases are characterized by an altered balance of T-cell phenotypes and cytokine secretion. STATs, therefore, represent viable therapeutic targets in numerous pathologies. However, the underlying mechanisms by which the same STAT proteins regulate both the development of different T-cell phenotypes and their plasticity during changes in extracellular conditions remain unclear. In this study, we investigated the STAT-mediated regulation of T-cell phenotype formation and plasticity using mathematical modelling and experimental data for intracellular STAT signalling proteins. The close fit of our model predictions to the experimental data allows us to propose a potential mechanism for T-cell switching. According to this mechanism, T-cell phenotype switching is the result of the relative redistribution of STAT dimer complexes caused by the extracellular cytokine-dependent STAT competition effects. The developed model predicts that the balance between the intracellular STAT species defines the amount of the produced cytokines and thereby T-cell phenotypes. The model predictions are consistent with the experimentally observed interferon-γ to interleukin-10 switching that regulates human T helper type 1/type 1 regulatory T-cell responses. The proposed model is applicable to a number of STAT signalling circuits.

Role of Th17 and Treg cells in septic arthritis and the impact of the Th17/Treg -derived cytokines in the pathogenesis of S. aureus induced septic arthritis in mice

Intravenous inoculation of Swiss mice with S. aureus leads to severe synovial joint tissue swelling along with prominent T lymphocyte infiltrate with associated inflammation in synovial tissue. Cytokines released from macrophages such as TNF-α, IL-1β and IL-6 the main players that precede cartilage and bone destruction during septic arthritis (SA) followed by osteoclast differentiation and bone resorption. CD4⁺ naïve T cells upon cytokine driven activation, differentiate into lineages of helper (Th) and regulatory T cells (Treg) including inflammatory Th17 cell lineage. Acting as counterbalance, Tregs protect the host by releasing anti-inflammatory IL-10. A disturbed balance between Th17 and Treg cell development skews the pathways towards Th17 lineage, but how it actually induces SA is still unexplored. Therefore, this study has been attempted to demonstrate the Th17/Treg ratio in synovial tissue, spleen and peripheral blood by FACS and their derived cytokines from serum of arthritic mice. Here, we reported that the ratios of Th17/Treg as well as their related cytokine levels were increased at 3 days post-infection which was decreased during 9 DPI but heightened again at 15DPI resulting in persistence of the disease, though decreased again at 30 DPI even in animals with increased dose of infection. Bacterial colonies were present in synovial joints at 15 DPI in animals with increased infection but found to be absent at 30 DPI. Maintaining Th17/Treg balance by neutralizing functionally active Th17 and their related cytokines or adoptive transfer of fully active Tregs and/or their related cytokines may lead to a novel therapeutic strategy for combating Staphylococcal arthritis.

Astilbin from Smilax glabra Roxb. Attenuates Inflammatory Responses in Complete Freund's Adjuvant-Induced Arthritis Rats

Astilbin, a flavonoid compound, was isolated from the rhizome of Smilax glabra Roxb. (with red cross-section) grown in Guizhou Province, China. We accessed its effect and potential mechanism on attenuation of the inflammatory response in CFA-induced AA rats. Our results showed that daily oral administration of astilbin at 5.3 mg/kg reduced joint damage in the hind paw of AA rats. Accordingly, astilbin exhibited remarkable inhibitory effects on TNF-α, IL-1β, and IL-6 mRNA expression. Significant decrease of serum cytokine levels of TNF-α, IL-1β, and IL-6 was also observed in astilbin-treated AA rats compared to the vehicle-treated AA rats. The reduced expression of these cytokines was associated with protein activity suppression of three key molecular targets in the pathogenesis of RA, including IKKβ, NF-κB p65 subunit, and TLR adaptor MyD88. Furthermore, the therapeutic effects of astilbin on the inhibition of cytokines production as well as the reduction of inflammatory response in AA rats are close to a commonly used antirheumatic drug, leflunomide. Collectively, our data suggest that the action mechanism of astilbin, as an anti-inflammatory agent for RA treatment, is associated with modulating the production of proinflammatory cytokines and inhibiting the expression of key elements in NF-κB signaling pathway mediated by TLR.

The β4GalT1 affects the fibroblast-like synoviocytes invasion in rheumatoid arthritis by modifying N-linked glycosylation of CXCR3

OBJECTIVE

The level of β-1,4-galactosyltransferase 1 (β4GalT1) is up-regulated in collagen-induced arthritis (CIA) mice. It is reported that CXC chemokine receptor 3 (CXCR3) can enhance the invasiveness of fibroblast-like synoviocytes (FLS) in rheumatoid arthritis (RA). This study aims to investigate the specific mechanism of β4GalT1 and relationship between β4GalT1 and CXCR3 in RA.

METHODS

The model of CIA mice was established to explore the role of β4GalT1. The N-glycosylation of CXCR3 was detected by mass spectrometry and western-blot. The interaction between β4GalT1 and CXCR3 was tested by immunoprecipitation. The truncted MMP-1 was detected by ELISA. Flow cytometry analysis was applied to measure ligand-receptor interaction between CXCR3 and CXCL10.

RESULTS

β4GalT1 can promote the inflammatory process of arthritis. CXCR3 was N-glycosylated and its glycosylation regulated by β4GalT1. β4GalT1 can enhance the invasiveness of FLS by modifying CXCR3. N-glycosylation of CXCR3 influences the ligand-receptor interaction between CXCR3 and CXCL10.

CONCLUSIONS

β4GalT1 can regulate N-glycans of CXCR3 in RA. N-glycans of CXCR3 affects CXCL10/CXCR3 ligand-binding which enhancing FLS invasion.

Biomolecular aspects of depression: A retrospective analysis

OBJECTIVE

The effects of psychological stress, oxidative stress, and chronic low grade inflammation on the neuro-immune connection have been implicated in the pathogenesis of depression. Thus, in the recent past, there has been a growing effort in determining the mechanism of this pathogenesis. While attempting to map out, this mechanism researchers and clinicians have searched for clinically relevant biomarkers for use in the diagnosis and for the assessment of those suffering from depression. In this study, we have performed a retrospective analysis of biomarkers with clinically relevant potentials, including peripheral catecholamines, chemokines, cytokines, and neurotransmitters.

METHODS

The retrospective analysis was performed on data collected over a six-year period of time (July 2009 to July 2015), gathered from patients (N=1399; Mage=42, SD=13; 71% female, 29% male) who submitted samples with complaints of feeling hopeless, worthless, isolated, alone, general sadness, overwhelmed, and/or a lack of interest in things they once enjoyed. The data collected consisted of quantitative values of urinary catecholamines and neurotransmitters (peripheral dopamine, epinephrine, histamine, kynurenic acid, norepinephrine, β-PEA, and serotonin), salivary hormones (peripheral cortisol and melatonin), and peripheral blood mononuclear cell secreted cytokines and chemokines (Interleukins 1β, 6, 8, 10, MCP-1, GCSF, and TNFα). Statistical and clinical significance was assessed by comparison with a control group (N=2395; Mage=42, SD=13; 70% female, 30% male), calculating the percent mean difference, p value, and effect size (Cohen's ɗ) for each parameter between groups.

RESULTS

The findings of this study suggested that, in a model of general depression, there is a dysregulation in the enzymatic production and degradation of catecholamines, neurotransmitters, hormones, and immunological proteins. A cycle of interaction was found between all of these biomolecules, where an increase or decrease in one marker could result in a stimulatory or inhibitory effect on others. The mechanism of this was proposed to occur through the interaction of psychological stress, inflammation, and oxidative stress pathways. All of these biomolecules were found to be significantly altered in the general depression group and are key components of the interaction between the neurological and immunological systems.

CONCLUSIONS

This study serves to further elucidate the role of biomolecules in the regulation of affective disorders, such as depression. Resulting in providing a network of clinically relevant biomarkers to objectively assess and monitor general depression.

Triphala exhibits anti-arthritic effect by ameliorating bone and cartilage degradation in adjuvant-induced arthritic rats

The present study was aimed to investigate the anti-arthritic effect of triphala and its underlying mechanism on adjuvant-induced rat model. For comparison purpose, non-steroidal anti-inflammatory drug indomethacin was used. Arthritis was induced by intradermal injection of complete Freund's adjuvant (0.1 ml) into the right hind paw of the Wistar albino rats. Triphala (100 mg/kg body weight [bwt]) was administered intraperitoneally (from 11th to 20th day) after the arthritis induction. Arthritis induction increased the levels of reactive oxygen species (LPO and NO), elastase, and mRNA expression of pro-inflammatory cytokines (TNF-α, IL-β, IL-17, IL-6 and MCP-1), inflammatory marker enzymes (iNOS and COX-2), receptor activator of nuclear factor kappa-B ligand (RANKL), and transcription factors (NF-kB p65 and AP-1) in the paw tissues of rats. The levels of bone collagen were found to decrease with increased urinary constituents (hydroxyproline and total glycosaminoglycans) in arthritic rats. In addition, the immunohistochemistry analysis revealed increased expression of NF-kBp65 and COX-2 in the paw tissues of arthritic rats. However, administration of triphala significantly inhibited the biochemical and molecular alterations in adjuvant-induced arthritic rats compared to indomethacin (3 mg/kg bwt) as evidenced by the radiological and histopathological analysis. In conclusion, our results suggest that triphala administration ameliorate bone and cartilage degradation during rheumatoid arthritis.

Combination therapy with metformin and coenzyme Q10 in murine experimental autoimmune arthritis

Metformin (Met) and coenzyme Q10 (CoQ10) are reported to have therapeutic functions in several inflammatory diseases. These drugs have shown anti-inflammatory effects and have been utilized in mouse models of rheumatoid arthritis (RA). However, there is no evidence of the additive effect of Met and CoQ10 in RA. Although Met and CoQ10 may be involved in the improvement of mitochondrial dysfunction, limited information is available regarding whether this effect can improve mitochondrial dysfunction in RA in particular. In this study, we sought to determine whether Met and CoQ10 attenuate the severity of collagen-induced arthritis (CIA) and show an additive effect in a mouse model. The combination of Met and CoQ10 improved CIA, reducing joint inflammation, Th17 differentiation and IgG production. In contrast, the combination of Met and CoQ10 induced Treg differentiation. Osteoclastogenesis was reduced by the combination of Met and CoQ10. The protein expression of interleukin-1β, interleukin-6 and tumor necrosis factor-alpha in mice splenocytes exposed to lipopolysaccharide decreased after drug combination therapy. We also found that the expression of JC-1 and COX IV were enhanced by treatment with the combination of Met and CoQ10. Moreover, the combination of Met and CoQ10 promoted mitochondrial O2 consumption. These findings suggest that the combination of Met and CoQ10 reduced CIA severity, improving mitochondrial dysfunction compared to Met or CoQ10 alone. These results present a novel, significant preventive targets in RA and may enhance our understanding of its pathogenesis.

Curcumin-loaded colloidal carrier system: formulation optimization, mechanistic insight, ex vivo and in vivo evaluation

The present work investigated the topical delivery potential of nanoemulsion gel loaded with curcumin (CR). CR nanoemulsion (CR-NE) was prepared by spontaneous emulsification method using oil (Labrafac PG/glyceryl triacetate), surfactant:cosurfactant (S_mix) (tween 80/polyethylene glycol [PEG] 400) and water. The pseudo-ternary phase diagrams were constructed and thermodynamic stability testing was performed. Droplet size and zeta potential were evaluated using photon correlation spectroscopy and transmission electron spectroscopy. Six formulations selected with an average droplet size ≤70±2.72 nm showed a fourfold increase in skin permeation as compared to crude CR solution in oil. The formulation CR-NE4 having a flux of 117.04±2.32 µg/cm²/h and with maximum retention (42.87%) was selected, characterized (droplet size =41.13±3.34 nm and zeta potential =−33.1±1.45 mV), and incorporated into gel using carbopol-980 (1% w/v). Skin dynamics analyzed by confocal laser scanning microscopy showed maximum deposition of CR up to a depth of 86.98 µm and was in concordance with differential scanning calorimetry and Fourier transform infrared spectroscopy studies that confirmed lipid bilayer disruption, enhancing permeation. A 28-day anti-arthritic evaluation (body weight, paw edema, tibiotarsal joint thickness, TNF-α and IL-1β levels, and histopathology) on Freund’s complete adjuvant induced arthritic rat model after topical application of CR-NE gel in Wistar rats demonstrated substantial reversal of arthritic symptoms. Thus, CR-NE gel possesses potential for therapeutic effects locally in inflammatory arthritic disorders with improved topical bioavailability.

Deletion of IFT20 in early stage T lymphocyte differentiation inhibits the development of collagen-induced arthritis

IFT20 is the smallest member of the intraflagellar transport protein (IFT) complex B. It is involved in cilia formation. Studies of IFT20 have been confined to ciliated cells. Recently, IFT20 was found to be also expressed in non-ciliated T cells and have functions in immune synapse formation and signaling in vitro. However, how IFT20 regulates T-cell development and activation in vivo is still unknown. We deleted the IFT20 gene in early and later stages of T-cell development by crossing IFT20(flox/flox) (IFT20(f/f) ) mice with Lck-Cre and CD4-Cre transgenic mice, and investigated the role of IFT20 in T-cell maturation and in the development of T cell-mediated collagen-induced arthritis (CIA). We found that both Lck-Cre/IFT20(f/f) and CD4-Cre/IFT20(f/f) mice were indistinguishable from their wild-type littermates in body size, as well as in the morphology and weight of the spleen and thymus. However, the number of CD4- and CD8-positive cells was significantly lower in thymus and spleen in Lck-Cre/IFT20(f/f) mice. Meanwhile, the incidence and severity of CIA symptoms were significantly decreased, and inflammation in the paw was significantly inhibited in Lck-Cre/IFT20(f/f) mice compared to Lck-Cre/IFT20(+/+) littermates. Deletion IFT20 in more mature T cells of CD4-Cre/IFT20(f/f) mice had only mild effects on the development of T cells and CIA. The expression of IL-1β, IL-6 and TGF-β1 were significantly downregulated in the paw of Lck-Cre/IFT20(f/f) mice, but just slight decreased in CD4-Cre/IFT20(f/f) mice. These results demonstrate that deletion of IFT20 in the early stage of T-cell development inhibited CIA development through regulating T-cell development and the expression of critical cytokines.

Zingiber officinale: A Potential Plant against Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease particularly affecting elderly people which leads to massive bone destruction with consequent inflammation, pain, and debility. Allopathic medicine can provide only symptomatic relief. However, Zingiber officinale is a plant belonging to the Zingiberaceae family, which has traditionally been used for treatment of RA in alternative medicines of many countries. Many of the phytochemical constituents of the rhizomes of this plant have therapeutic benefits including amelioration of RA. This review attempts to list those phytochemical constituents with their reported mechanisms of action. It is concluded that these phytochemicals can form the basis of discovery of new drugs, which not only can provide symptomatic relief but also may provide total relief from RA by stopping RA-induced bone destruction. As the development of RA is a complex process, further research should be continued towards elucidating the molecular details leading to RA and drugs that can stop or reverse these processes by phytoconstituents of ginger.

Plasma levels of IL-37 and correlation with TNF-α, IL-17A, and disease activity during DMARD treatment of rheumatoid arthritis

The aim of this study was to assess the change of IL-37 concentrations in rheumatoid arthritis (RA) patients under Disease-modifying anti-rheumatic drug (DMARD) therapy, and to establish a correlation between Interleukin-37 and pro-inflammatory cytokines in plasma and disease activity. The plasma level of IL-37 was determined using ELISA in 50 newly diagnosed RA patients and 30 healthy controls (HC). Plasma levels of IL-17A, IL-6 and TNF-α were measured using flow a cytometric bead array assay. We found that the concentrations of IL-37, as well as IL-17A, IL-6 and TNF-α, were higher in plasma of RA patients compared to HCs. Compared to patients who did not respond to DMARD treatment, treatment of patients responsive to DMARDs resulted in down-regulation of IL-17A, IL-6 and TNF-α expression. The plasma level of the anti-inflammatory cytokine IL-37 was also decreased in drug responders after DMARD treatment. The plasma level of IL-37 in RA patients was positively correlated with pro-inflammatory cytokines (IL-17A, TNF-α) and disease activity (CRP, DAS28) in RA patients. IL-37 expression in RA and during DMARD treatment appears to be controlled by the level of pro-inflammatory cytokines. This results in a strong correlation between plasma levels of IL-37 and disease activity in RA patients.

Strategies for active TNF-α vaccination in rheumatoid arthritis treatment

Local overexpression of tumor necrosis factors alpha (TNF-α) is critically involved in the inflammatory response and tissue destruction of rheumatoid arthritis (RA). Currently, the blockade of TNF-α by passive immunotherapy is indeed efficacious in the treatment of RA, but it still present some disadvantages. Induction of high level of anti-TNF-α neutralizing autoantibodies by TNF-α autovaccine has been developed to avoid these shortcomings. This review is to briefly introduce several vaccination approaches that have been used to induce a B cell response, including coupled TNF-α (entire/peptide) with a carrier protein, modified TNF-α with foreign Th cell epitopes, and engineered DNA vaccine. These methods showed remarkable therapeutic efficiency in experimental animals which indicated that active TNF-α immunization would be a promising and cost-effective new treatment option for RA.