Glucocorticoids in Rheumatoid Arthritis

Integrated Network Pharmacology and Experimental Validation Approach to Investigate the Mechanisms of Stigmasterol in the Treatment of Rheumatoid Arthritis

Background

Rheumatoid arthritis (RA) is a chronic inflammatory disease of the joints associated with systemic comorbidities. Sinomenium acutum is regarded as an effective traditional Chinese medicine (TCM) for the treatment of RA.

Materials and Methods

Based on network pharmacology and Gene Expression Omnibus (GEO) database, 33 RA-related differentially-expressed genes (DEGs) targeting active compounds of Sinomenium acutum were initially screened in our investigation.

Results

Gene Ontology (GO) and Kyoto encyclopaedia of genes and genome (KEGG) analyses found the important involvement of these DEGs in osteoclast differentiation, and finally 5 core DEGs, including NCF4, NFKB1, CYBA, IL-1β and NCF1 were determined through protein-protein interaction (PPI) network. We also identified the related active component of Sinomenium acutum include Stigmasterol. Finally, in order to experimentally verify these results, a rat model of collagen-induced arthritis (CIA) was established, and subsequently treated with Stigmasterol solution.

Conclusion

Similar to the healing effect of Indomethacin, Stigmasterol was observed to reduce the levels of inflammatory factors (IL-6 and IL-1β) and osteoclast differentiation-related factors (RANKL, ACP5 and Cathepsin K), which can also reduce the arthritis index score and alleviate the degree of pathological injury of rat ankle joints. The predictions and experimental data uncover the involvement of Stigmasterol, an active component of Sinomenium acutum, in regulation of osteoclast differentiation, exerting great medicinal potential in the treatment of RA.

Effective natural inhibitors targeting granzyme B in rheumatoid arthritis by computational study

Background

Rheumatoid arthritis (RA) is an autoimmune disease characterized by erosive arthritis, and current treatments for RA fall short of the outcomes expected by clinicians and patients.

Objectives

This study aimed to identify novel therapeutic and prognostic targets in RA at the genomic level and to screen desirable compounds with potential inhibitory effects on GZMB.

Methods

We performed differential gene analysis on GSE55235 and GSE55457 from Gene Expression Omnibus (GEO) and then obtained the intersection of the two differentially expressed genes (DEGs) lists by drawing Venn diagrams. Then we performed protein-protein interaction (PPI) network analysis, Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis on the DEGs of the intersection. Next, we downloaded the crystal structure of Granzyme B (GZMB). Molecular docking technology was used to screen potential inhibitors of GZMB in subsequent experiments, and we then analyzed the toxicity and water solubility of these potential inhibitors for future drug experiments. Finally, whether the docking of these small molecules with GZMB is stable is tested by molecular dynamics.

Results

A total of 352 mutual DEGs were identified. Twenty hub genes were obtained according to PPI network analysis, among which the GZMB gene attracted the attention of our research. Three potent natural compounds, ZINC000004557101, ZINC000012495776, and ZINC000038143593, bound to GZMB, show better binding affinity. Furthermore, they are predicted to own low Ames mutagenicity, developmental toxicity potential, rodent carcinogenicity, and high tolerance to cytochrome P4502D6. Molecular dynamics simulations show that ZINC000004557101 and GZMB have more advantageous potential energy and can exist stably in a natural environment. Moreover, we finally verified the inhibitory effect of ZINC000004557101 on granzyme B by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Western blotting experiment.

Conclusion

RA patients showed increased GZMB expression. ZINC000004557101 is a potential drug targeting GZMB for treating RA.

Nanomedicine Strategies for Anti-Inflammatory Treatment of Noninfectious Arthritis

Noninfectious arthritis (NIA) comprises a class of chronic and progressive inflammatory disorders that require early-stage management to prevent disease progression. The most common forms include osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, and gouty arthritis. Current treatments involve nonsteroidal anti-inflammatory drugs, disease-modifying antirheumatic drugs and glucocorticoids to alleviate clinical symptoms, although regular use of these can result in a high risk of chronic kidney disease and heart failure, as well as severe adverse gastrointestinal effects. Nanomedicine offers unique opportunities to address these challenges and improve therapeutic efficacy due to its ability to deliver therapeutics locally in a sustained manner, thus extending the half-life, improving bioavailability, and reducing the side effects of these agents. This review includes a comprehensive analysis of the mechanisms of various treatment options for NIA and highlights recent progress and emerging strategies in treating NIA with nanomedicine platforms, particularly related to long-term biosafety and nonspecific targeting in designing nanomedicine delivery systems.

"Official View" on Glucocorticoids in Rheumatoid Arthritis: A Systematic Review of International Guidelines and Consensus Statements

OBJECTIVE

To describe the perception of the current role of systemic glucocorticoids in the management of rheumatoid arthritis (RA) by examining their importance and the current level of evidence in recent guidelines, and to identify open questions to be addressed in future guidelines and research projects.

METHODS

We conducted a systematic literature review using the databases Ovid Embase, PubMed Medline, and Cochrane Library for guidelines on the pharmacologic treatment of RA. Retrieved articles were evaluated regarding their quality using the Appraisal of Guidelines for Research and Evaluation II tool and scrutinized for all relevant information concerning the use of glucocorticoids.

RESULTS

All guidelines agree that glucocorticoids, especially if given at low doses and for a short duration, are an appropriate option in the treatment of RA. However, many recommendations remain vague, as reliable and detailed evidence is scarce. Important aspects of glucocorticoid therapy are partially or completely neglected, and the existing nomenclature is not used uniformly. Quality evaluation revealed flaws in many articles, concerning not only glucocorticoid-specific recommendations but also guideline quality in general.

CONCLUSION

Current recommendations for use of glucocorticoids in the management of RA are suboptimal. More rigorous evaluation of doses, timing, and duration of their use is needed. Existing nomenclature on glucocorticoid therapy should be used uniformly.

Liposomal Treatment of Experimental Arthritis Can Be Monitored Noninvasively with a Radiolabeled Anti-Fibroblast Activation Protein Antibody

Rheumatoid arthritis is a chronic autoimmune disorder resulting in synovial inflammation. Fibroblast activation protein (FAP) is overexpressed by fibroblastlike synoviocytes in arthritic joints. Radioimmunoimaging with an anti-FAP antibody might be used to monitor the response to therapy, thus enabling tailored therapy strategies and therapeutic outcomes. The aim of this study was to assess whether a radiolabeled anti-FAP antibody could be used to monitor the efficacy of treatment with long-circulating liposomes (LCL) containing prednisolone phosphate (PLP-LCL) in a mouse model of arthritis.

METHODS

Collagen-induced arthritis (CIA) was induced in male DBA/1J mice. Mice were treated with a single injection (10 mg/kg) of PLP-LCL or empty LCL as a control. SPECT and CT images were acquired 24 h after injection of ^99mTc-labeled succinimidyl-hydrazinonicotinamide (^99mTc-S-HYNIC)-conjugated anti-FAP antibody 28H1 at 2, 5, and 9 d after treatment. The uptake of ^99mTc-S-HYNIC-28H1 in all joints was quantified and correlated with macroscopic arthritis scores.

RESULTS

Treatment of CIA with PLP-LCL significantly suppressed joint swelling. At just 1 d after treatment, the macroscopic arthritis scores had decreased by 50%. Scores decreased further, to only 10% of the initial scores, at 5 and 9 d after treatment. In contrast, macroscopic arthritis scores had increased up to 600% in untreated mice at 9 d after the injection of empty LCL. ^99mTc-S-HYNIC-28H1 uptake ranged from 1.5 percentage injected dose per gram in noninflamed joints to 22.6 percentage injected dose per gram in severely inflamed joints. The uptake of radiolabeled 28H1 in inflamed joints (percentage injected dose) correlated with the arthritis score (Spearman ρ, 0.77; P < 0.0001). Moreover, the uptake of ^99mTc-S-HYNIC-28H1 was slightly increased at 9 d after therapy but was not seen macroscopically, indicating that SPECT/CT imaging might be more sensitive than the macroscopic arthritis scoring method.

CONCLUSION

SPECT/CT imaging with ^99mTc-S-HYNIC-28H1 specifically monitored the response to therapy, and tracer accumulation correlated with the severity of inflammation. In addition, SPECT/CT imaging was potentially more sensitive than the macroscopic arthritis scoring method. This study showed that SPECT/CT with ^99mTc-S-HYNIC-28H1 could be used to noninvasively monitor the course of CIA in mice.

Martingale residual-based method to control for confounders measured only in a validation sample in time-to-event analysis

Unmeasured confounding remains an important problem in observational studies, including pharmacoepidemiological studies of large administrative databases. Several recently developed methods utilize smaller validation samples, with information on additional confounders, to control for confounders unmeasured in the main, larger database. However, up-to-date applications of these methods to survival analyses seem to be limited to propensity score calibration, which relies on a strong surrogacy assumption. We propose a new method, specifically designed for time-to-event analyses, which uses martingale residuals, in addition to measured covariates, to enhance imputation of the unmeasured confounders in the main database. The method is applicable for analyses with both time-invariant data and time-varying exposure/confounders. In simulations, our method consistently eliminated bias because of unmeasured confounding, regardless of surrogacy violation and other relevant design parameters, and almost always yielded lower mean squared errors than other methods applicable for survival analyses, outperforming propensity score calibration in several scenarios. We apply the method to a real-life pharmacoepidemiological database study of the association between glucocorticoid therapy and risk of type II diabetes mellitus in patients with rheumatoid arthritis, with additional potential confounders available in an external validation sample. Compared with conventional analyses, which adjust only for confounders measured in the main database, our estimates suggest a considerably weaker association. Copyright © 2016 John Wiley & Sons, Ltd.

[(18)]F FDG PET/CT imaging to monitor the therapeutic effect of liposome-encapsulated prednisolone in experimental rheumatoid arthritis

Current treatment of rheumatoid arthritis includes systemic administration of glucocorticoids. To improve joint targeting and anti-inflammatory efficacy these glucocorticoids are encapsulated in long-circulating liposomes. The present study aimed to monitor therapeutic effects of prednisolone (PLP)-containing PEG-liposomes in murine antigen-induced arthritis (AIA) using [(18)F]FDG PET/CT. Mono-articular arthritis was induced in male C57Bl6/J mice. At 0, 3, 7 and 12 days after arthritis induction, inflamed joints were macroscopically scored (0 = unaffected to 4 = immobile) and [(18)F]FDG PET/CT images were acquired. In a second experiment, to study the feasibility to monitor therapeutic effects of PLP encapsulating PEG-liposomes, mice were treated with a single i.v. injection of PLP-containing PEG-liposomes (10 mg/kg) or empty PEG-liposomes 3 days after arthritis induction. Inflamed joints were macroscopically scored and images were acquired at -3, 0, 4 and 9 days after treatment. PET images were analyzed quantitatively, and mice were dissected to allow histological analysis of the joints. With progression of arthritis, [(18)F]FDG uptake in inflamed joints increased significantly (day 0: 2.5 ± 0.9%ID/ml, day 7: 4.4 ± 0.4%ID/ml, p = 0.0159), while no changes were observed in unaffected paws (day 0: 2.5 ± 1.1%ID/ml, day 7: 2.7 ± 0.8%ID/ml, p = 0.3466). In the second experiment, macroscopic scoring revealed suppression of joint swelling after treatment with PLP-containing PEG-liposomes. In line with that, [(18)F]FDG uptake did not change in the treated mice (day -3: 1.9 ± 0.3%ID/ml, day 4: 2.2 ± 0.2%ID/ml, p = 0.3466), while it increased in mice that developed arthritis (day -3: 2.0 ± 0.2%ID/ml, day 4: 3.1 ± 0.6%ID/ml, p = 0.0225). Histological analysis confirmed therapeutic efficacy, which showed less inflammation (p = 0.0354) and bone erosion (p = 0.0298) in treated mice. These data show that [(18)F]FDG PET/CT could be used to monitor the progression of AIA and confirmed rapid and profound anti-inflammatory effects of PLP-containing PEG-liposomes that were also observed macroscopically and microscopically.

Oral low-dose glucocorticoids should be included in any recommendation for the use of non-biologic and biologic disease-modifying antirheumatic drugs in the treatment of rheumatoid arthritis

At present, growing scientific evidence from the medical literature and expert opinion provides strong consideration for a mandatory role of glucocorticoids (GCs) in the management of rheumatoid arthritis (RA). Earlier application strategies were based on initial high doses, with subsequent tapering schedules, resulting in dose-related side effects. Recent low-dose GC schemes are more feasible in routine care, while providing evidence of clinical, functional and structural efficacy. Thus, initial low-dose GC 'bridging' treatment on a disease-modifying antirheumatic drug background should be included in any existing recommendations for RA management, as very recently advocated by the EULAR Task Force 2013 updated guidelines. Long-term low-dose therapy appears to provide acceptable safety, leading to long-standing slowing of structural damage, seen even after GC therapy withdrawal. Gaps in knowledge about the optimal method to taper and possibly discontinue GC treatment remain, and this topic should be addressed in clinical trials and observational studies. Recent efforts in GC medication have also included the introduction of a modified-release drug formulation capable of drug delivery consistent with chronobiological pathogenetic rhythms of disease, which has been quite efficacious in controlling the signs and symptoms related to pathways of circadian cytokines. Long-term data will further clarify the add-on benefits of such modified-release formulations.

Modified-release prednisone: in patients with rheumatoid arthritis

Prednisone is a well-established treatment option in rheumatoid arthritis. Low-dose glucocorticoid therapy alleviates disease signs and symptoms, is better tolerated than high-dose therapy, and its addition to disease-modifying anti-rheumatic drugs (DMARDs) inhibits radiographic disease progression. A low-dose, modified-release (MR) formulation of prednisone, administered in the evening, was developed to counter the circadian rise in pro-inflammatory cytokine levels that contributes to disease activity. In a 12-week, randomized trial (CAPRA-2) in adult patients with rheumatoid arthritis who were receiving stable DMARD therapy, the addition of MR prednisone reduced disease signs and symptoms by ≥20 % according to the American College of Rheumatology criteria (in 48 % of patients vs. 29 % with placebo; p < 0.002 [primary endpoint]). In another 12-week trial (CAPRA-1), addition of evening MR prednisone to stable DMARD therapy reduced the mean duration of morning stiffness to a greater extent than addition of morning immediate-release (IR) prednisone (22.7 vs. 0.4 %; p = 0.045 [primary endpoint]). The improvement in morning stiffness with MR prednisone was maintained for 9-12 months during the open-label extension of CAPRA-1. These findings were supported by data from observational studies in various adult populations with rheumatoid arthritis. Treatment with evening MR prednisone for up to 12 months was generally well tolerated, with an overall similar tolerability profile compared with evening placebo or morning IR prednisone, and no new safety concerns. MR prednisone was estimated to be cost effective relative to IR prednisone in patients with rheumatoid arthritis in a UK pharmacoeconomic model.