JAK/STAT/PKCδ molecular pathways in synovial fluid T lymphocytes reflect the in vivo T helper-17 expansion in psoriatic arthritis

JAK Inhibitors in Psoriatic Disease

Psoriasis is now considered to be the cutaneous phenotype of a systemic inflammatory condition, recognized under the term Psoriatic Disease (PsD). PsD has several extracutaneous manifestations, such as inflammatory articular and entheseal involvement, leading to psoriatic arthritis (PsA), and the less frequent intestinal and ocular manifestations with colitis/inflammatory bowel disease and uveitis, respectively. There have also been several reports of an increased frequency of comorbidities such as hypertension, diabetes, dyslipidemia, obesity, metabolic syndrome and cardiovascular manifestations during the course of PsD. The link between psoriasis and related comorbidities is considered a long-term disease sequela, often characterized by an unhealthy lifestyle and a consequence of systemic inflammation; hence, psoriasis requires adequate and prompt treatment, with the aim of controlling not only cutaneous manifestations but also extracutaneous manifestations and systemic inflammation. Pharmacological strategies for PsD have significantly increased over recent years. Recently, the targeted synthetic DMARDs, Janus kinase (JAK) inhibitors, tofacitinib and upadacitinib, were added to the therapeutic armamentarium for treating PsA, and deucravacitinib for psoriasis. These oral agents act directly on inflammatory mechanisms underlining the disease, as antagonists of the intracellular JAK signal pathway and, by STAT phosphorylation, inhibit gene proinflammatory cytokine transcription. JAK inhibitors represent a recent additional treatment strategy for PsD management and, among these, tofacitinib and upadacitinib have recently been approved for PsA, and deucravacitinib for psoriasis. In this review we describe ongoing and recent phase II and III randomized controlled trials (RCTs) evaluating the efficacy and safety of investigational JAK inhibitors in psoriasis and PsA.

Drug Target Identification and Drug Repurposing in Psoriasis through Systems Biology Approach, DNN-Based DTI Model and Genome-Wide Microarray Data

Psoriasis is a chronic skin disease that affects millions of people worldwide. In 2014, psoriasis was recognized by the World Health Organization (WHO) as a serious non-communicable disease. In this study, a systems biology approach was used to investigate the underlying pathogenic mechanism of psoriasis and identify the potential drug targets for therapeutic treatment. The study involved the construction of a candidate genome-wide genetic and epigenetic network (GWGEN) through big data mining, followed by the identification of real GWGENs of psoriatic and non-psoriatic using system identification and system order detection methods. Core GWGENs were extracted from real GWGENs using the Principal Network Projection (PNP) method, and the corresponding core signaling pathways were annotated using the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Comparing core signaling pathways of psoriasis and non-psoriasis and their downstream cellular dysfunctions, STAT3, CEBPB, NF-κB, and FOXO1 are identified as significant biomarkers of pathogenic mechanism and considered as drug targets for the therapeutic treatment of psoriasis. Then, a deep neural network (DNN)-based drug-target interaction (DTI) model was trained by the DTI dataset to predict candidate molecular drugs. By considering adequate regulatory ability, toxicity, and sensitivity as drug design specifications, Naringin, Butein, and Betulinic acid were selected from the candidate molecular drugs and combined into potential multi-molecule drugs for the treatment of psoriasis.

Recent developments for new investigational JAK inhibitors in psoriatic arthritis

INTRODUCTION

Psoriatic arthritis (PsA) is a chronic inflammatory disease affecting about one-third of subjects with psoriasis. Several treatment modalities targeting Janus Kinase pathways and intracellular inflammatory cascade are now available and under clinical investigation to treat this disease.

AREAS COVERED

This review describes ongoing and recently completed phase 2 and 3 Randomized Clinical Trials (RCTs) evaluating the efficacy and safety of approved JAK (Tofacitinib and Upadacitinib) and investigational JAK inhibitors (JAK1 inhibitors: Filgotinib and Ivarmacitinib (SHR0302); TYK2 inhibitors: Brepocitinib (PF-06700841) Deucravacitinib (BMS-986165), and NDI-034858) in PsA through February 2023.

EXPERT OPINION

Current standard of care has significantly improved the quality of life in PsA. Recently approved JAK inhibitors for PsA have addressed many of the unmet needs of PsA, particularly of those with severe phenotypes. Preliminary results from several RCTs have reported good and fast efficacy and an acceptable safety profile of investigational JAK inhibitors in PsA. Additional clinical trials and long-term outcome data on these agents are necessary for increasing available therapeutic options for PsA.

Upadacitinib for the treatment of psoriatic arthritis

Psoriatic arthritis is a chronic systemic inflammatory disease that presents with a variable clinical course and is typically associated with joint inflammation, together with cutaneous psoriasis. In recent decades, knowledge of the pathogenesis of psoriatic arthritis has advanced considerably and has allowed for development of new highly effective therapies, transforming the treatment landscape. Upadacitinib is a Janus kinase inhibitor (JAK) that is orally reversible with high selectivity for JAK1 and its signal transduction molecules. The results obtained in the phase III clinical trials (SELECT-PsA 1 and SELEC-PsA 2) demonstrated that upadacitinib was highly effective over placebo and non-inferior to adalimumab in several important domains of the disease. Improvements were observed in dactylitis, enthesitis and spondylitis as well as in physical function, pain, fatigue and overall quality of life. The safety profile of these results resembled that of adalimumab, apart from a slightly higher rate of herpes zoster infection, an increase of creatine kinase and an incidence of lymphopenia. However, none of these events was considered a serious adverse advent. Additionally, another analysis demonstrated that combining upadacitinib with methotrexate was associated with a similar efficacy to upadacitinib in monotherapy, both for patients that are naive to biologics treatment and for those previously treated with biologics. Therefore, upadacitinib is a new option for the treatment of psoriatic arthritis, presenting a series of beneficial characteristics. At this stage, it is important to collect long-term data to confirm the efficacy and safety profiles shown in clinical trials.

Peripheral Treg Levels and Transforming Growth Factor-β (TGFβ) in Patients with Psoriatic Arthritis: A Systematic Review Meta-Analysis

INTRODUCTION

Studies on the level of regulatory T (T_reg) cells in psoriatic arthritis (PsA) have been controversial, leading to disagreement regarding the role T_reg cells play in the pathogenesis of the disease. To clarify the status of T_reg cells in patients with PsA, we performed a meta-analysis to determine the levels of T_reg cells and serum T_reg-associated cytokines in PsA patients.

METHODS

According to published data from PubMed, Web of Science, Embase, Clinical Trials.gov, MEDLINE, Web of Knowledge, Cochrane Library, and FDA.gov, we determined the T_reg and T_reg cytokine levels in patients with PsA. The effect estimates were pooled using a random-effects model.

RESULTS

This meta-analysis included 12 studies. Compared to healthy controls (HCs), the proportions of T_reg cells had no significant difference in patients with PsA (based on standardized means[SMD] = - 1.038, 95% confidence intervals[CI] =  - 2.165 to 0.089, p = 0.071). On the basis of subgroup analysis, patients with PsA had a lower percentage of CD4⁺ T_reg cells (SMD = - 1.501, 95% CI - 2.799 to - 0.202, p = 0.023) than OKT8⁺ T_reg (SMD = 0.568, 95% CI - 2.127 to 3.263, p = 0.679). Besides, CD4⁺CD25⁺FoxP3⁺ T_reg cells and CD4⁺CD25^highCD127^low T_reg cells were both significantly decreased on the levels of PBMCs in patients with PsA (SMD = - 0.764, 95% CI - 1.404 to - 0.125, p = 0.019; SMD = - 5.184, 95% CI - 6.955 to - 3.412, p < 0.001). CD4⁺CD25⁺FoxP3⁺ T_reg cells were particularly more abundant in the synovial fluid thanin peripheral blood (SMD = 3.288, 95% CI 2.127 to 4.449, p < 0.001). No significant difference was observed in the proportion of CD4⁺CD25⁺ T_reg cells in peripheral blood and CD4⁺CD25⁺FoxP3⁺ T_reg cells in CD4⁺ T cells (SMD = - 2.498, 95% CI - 7.720 to 2.725, p = 0.349; SMD = - 0.719, 95% CI - 2.525 to 1.086, p = 0.435). PsA patients had decreased cytokines such as transforming growth factor-β (TGFβ) (SMD = - 2.199, 95% CI - 3.650 to - 0.749, p = 0.003).

CONCLUSIONS

T_reg definition markers influence the scale of T_reg cells in patients with PsA. Pathogenesis of PsA may be attributed to an insufficient or malfunctioning T_reg population.

Aruncus dioicus var. kamtschaticus Extract Ameliorates Psoriasis-like Skin Inflammation via Akt/mTOR and JAK2/STAT3 Signaling Pathways in a Murine Model

Goat's beard (Aruncus dioicus var. kamtschaticus) is a traditional medicinal plant, widely used in Chinese and Korean traditional medicine because of its anti-inflammatory, anti-oxidant, antimicrobial, and anti-cancer activity. However, its effect on skin inflammatory diseases like psoriasis is unknown. The aim of this study was to investigate the therapeutic potency of A. dioicus extract (ADE) in in vitro and in vivo psoriasis models. ADE treatment significantly attenuated skin inflammation and improved skin integrity in imiquimod-treated mice by suppressing keratinocyte hyperproliferation, inhibiting the infiltration of immune cells, and downregulating the expression of psoriatic markers. Further, ADE treatment suppressed protein kinase B/mammalian target of rapamycin (Akt/mTOR) and Janus kinase 2/signal transducers and activators of transcription 3 (JAK2/STAT3) signaling in HaCaT cells. Overall, the application of ADE relieves psoriasis-like skin inflammation possibly by regulating the Akt/mTOR and JAK2/STAT3 signaling pathways, making it an effective alternative for psoriasis therapy.

Analysis of rheumatoid- vs psoriatic arthritis synovial fluid reveals differential macrophage (CCR2) and T helper subsets (STAT3/4 and FOXP3) activation

OBJECTIVE

In psoriatic arthritis (PsA) and rheumatoid arthritis (RA), inflammatory responses are characterized by increased production of pro-inflammatory molecules secreted by various immune cells. The main objectives of our study were: i) to measure levels of pro- and anti-inflammatory cyto-chemokines and soluble factors expressed in both PsA and RA SF; ii) to characterize the phenotype of infiltrated leuko-lymphocytes and; iii) to identify specific synovial biomarkers for both diseases. Notably, Synovial Fluid (SF) samples obtained from PsA and RA populations were compared with SF samples collected from clinically active osteoarthritis (OA) joints.

METHODS

SF samples were collected from clinically active knee arthritis of PsA, RA and OA patients and assayed for cyto-chemokines profile and macrophage and T helper subsets markers and transcriptional factors by Elisa Spot and western blot.

RESULTS

our study revealed that modulation of CCL-2, G-CSF, IL-1β and TNF-α is peculiar and specific to RA synovial fluid, whereas we detected more significant levels of ICAM-1, IL-2, IL-6, IL-17A, C5a and CXCL-9/12 in PsA compared to RA patients. We also found that CCR2 expression appeared to be significantly upmodulated in PsA and, even more, in RA group, as well as the expression of specific Th and Treg transcriptional factors as STAT3/4 and FOXP3.

CONCLUSION

Even though this study has several limitations, we identified a heterogenous scenario of peculiar molecular pathway and soluble mediators' production that characterize PsA and RA SF that may be useful in understanding the complex pattern of macrophages and lymphocytes infiltration in both pathologies and, potentially, pave the way for personalized precision therapies.

What's new and what's next for biological and targeted synthetic treatments in psoriatic arthritis?

INTRODUCTION

Psoriatic arthritis (PsA) is a chronic arthritis typically associated with cutaneous psoriasis (PsO). Its pathogenesis is connected to an innate and acquired immune response, as well as genetic risk alleles. The extent of immunopathogenic mechanisms and the heterogenicity of clinical manifestation make the identification of patient-targeted therapies a critical issue, and the treatment decision challenging in patients' management.

AREAS COVERED

This review includes a brief overview of biological and small-molecule therapies, focusing on evidence from clinical trials and real-world data that support their use in PsA. We summarize novel and future possible therapeutic strategies, the importance that comorbidities have on selection of therapy and discuss the adverse event of each drug. Relevant papers for up to 1 August 2022 (trials, real-life studies, and reviews) regarding biologics and/or small molecules were summarized.

EXPERT OPINION

In recent years, the treatment of PsA has been revolutionized by new targeted therapies, which offer the opportunity to perform a tailored-tail management, considering risk factors, comorbidities, and the different PsA phenotypes. Growing experience with these new agents allows novel treatment approaches that may improve clinical outcomes for PsA patients, in terms of remission/low disease activity and quality of life.

Psoriatic arthritis from a mechanistic perspective

Psoriatic arthritis (PsA) is part of a group of closely related clinical phenotypes ('psoriatic disease') that is defined by shared molecular pathogenesis resulting in excessive, prolonged inflammation in the various tissues affected, such as the skin, the entheses or the joints. Psoriatic disease comprises a set of specific drivers that promote an aberrant immune response and the consequent development of chronic disease that necessitates therapeutic intervention. These drivers include genetic, biomechanical, metabolic and microbial factors that facilitate a robust and continuous mobilization, trafficking and homing of immune cells into the target tissues. The role of genetic variants involved in the immune response, the contribution of mechanical factors triggering an exaggerated inflammatory response (mechanoinflammation), the impact of adipose tissue and altered lipid metabolism and the influence of intestinal dysbiosis in the disease process are discussed. Furthermore, the role of key cytokines, such as IL-23, IL-17 and TNF, in orchestrating the various phases of the inflammatory disease process and as therapeutic targets in PsA is reviewed. Finally, the nature and the mechanisms of inflammatory tissue responses inherent to PsA are summarized.

High Dimensional Analyses of Circulating Immune Cells in Psoriatic Arthritis Detects Elevated Phosphorylated STAT3

Psoriatic arthritis (PsA) is a chronic inflammatory arthritis, affecting up to 40% of patients with psoriasis. Constitutive expression by CD4+ T cells of an active form of STAT3, a signal transducer and transcription factor, has been shown to induce many of the major features of PsA in an animal model. We used high dimensional mass cytometry (CyTOF) to probe ex-vivo levels of phosphorylated STAT3 (pSTAT3) in circulating immune cell subpopulations from PsA patients during active and inactive states. We evaluated the frequency of 16 immune cell populations and the levels of the activated forms of STAT3 (pSTAT3) and, for comparison, STAT1 (pSTAT1) and Src (pSrc) in whole blood fixed shortly after collection. In addition to PsA patients, we studied active rheumatoid arthritis (RA) patients. Increased levels of pSTAT3 were found in all the CD4+ T cell subsets analyzed, specifically, Th1, Th2, Th17, T follicular helper (Tfh) and T regulatory (Treg) as well as in CD14+CD16- (classical) monocytes from active PsA patients compared to inactive patients. After correcting for body mass index (BMI), smoking and conventional disease modifying antirheumatic drugs (c-DMARDs), levels of pSTAT3 levels remained increased in Th1 and Tfh CD4+ T cells, and in CD14+CD16- monocytes from active patients compared to inactive patients. No differences between the patient groups were observed for pSTAT1 or pSrc. No differences were found between the active PsA and active RA groups after correction for multiple testing. During active PsA, circulating Th1 and Tfh CD4+ T cells, and CD14+CD16- monocytes expressing high levels of pSTAT3 may play a role in PsA pathophysiology, perhaps by migration to inflamed sites.

Proteomimetics of Natural Regulators of JAK-STAT Pathway: Novel Therapeutic Perspectives

The JAK-STAT pathway is a crucial cellular signaling cascade, including an intricate network of Protein-protein interactions (PPIs) responsible for its regulation. It mediates the activities of several cytokines, interferons, and growth factors and transduces extracellular signals into transcriptional programs to regulate cell growth and differentiation. It is essential for the development and function of both innate and adaptive immunities, and its aberrant deregulation was highlighted in neuroinflammatory diseases and in crucial mechanisms for tumor cell recognition and tumor-induced immune escape. For its involvement in a multitude of biological processes, it can be considered a valuable target for the development of drugs even if a specific focus on possible side effects associated with its inhibition is required. Herein, we review the possibilities to target JAK-STAT by focusing on its natural inhibitors as the suppressor of cytokine signaling (SOCS) proteins. This protein family is a crucial checkpoint inhibitor in immune homeostasis and a valuable target in immunotherapeutic approaches to cancer and immune deficiency disorders.

Exploring the Diverse Immune and Genetic Landscape of Psoriatic Arthritis

Psoriatic arthritis (PsA) is characterized by delays in diagnosis and modest effect of treatment in terms of joint response. An understanding of molecular pathomechanisms may aid in developing diagnostic and prognostic models. Genetic susceptibility (e.g., HLA class I genes, IL-23-related genes) can be responsible for the pattern of psoriatic manifestations and affinity for tissue involvement. Gene expression analysis indicates an inflammatory profile that is distinct for PsA, but disparate across tissues. This has clinical implications, as for example, dual blockade of IL-17A and IL-17F can lead to superior clinical effects if there is differential expression of IL-17 receptors in tissues. Structural and functional impairment of barrier tissue, including host-microbiome interactions, may be the source of immune activation. Interplay between different cell populations of innate and adaptive immunity is emerging, potentially providing a link between the transition of skin-to-joint disease. Th17 subsets, IL-17A, IL-17F and IL-23 are crucial in PsA pathogenesis, with both clinical and experimental evidence suggesting a differential molecular landscape in cutaneous and articular compartments.

Tanshinone IIA and Astragaloside IV Inhibit miR-223/JAK2/STAT1 Signalling Pathway to Alleviate Lipopolysaccharide-Induced Damage in Nucleus Pulposus Cells

Astragaloside IV (AS IV) and tanshinone (TS IIA) are the main natural components of Salvia miltiorrhiza and Radix Astragali, respectively. The amalgam of TS IIA and AS IV has potential therapeutic value in many inflammation-related diseases. However, the aftereffect of TS IIA and AS IV for lumbar disc herniation is not clear. Although the function of miR-223 in the inflammation-related JAK/STAT pathway is unknown, it is particularly expressed in human degenerative nucleus pulposus cells. This study has investigated the efficacy of the combined application of TS IIA and AS IV in the treatment of intervertebral disc nucleus pulposus cells (NP cells) injured by lipopolysaccharide (LPS). After miR-223 inhibitor imitated NP cells, the state of the JAK family and STAT family was recognized by Western blotting (Western blot, WB) and reverse transcriptase quantitative polymerase chain reaction (qPCR). The shRNA lentivirus interference vector targeting the STAT family was constructed, and the NP cell line stably interfering with the STAT gene was established after transfection. The expression of TNF-α, IL-6, MMP-9, MMP-3, caspase-1, and caspase-3 was detected by lipopolysaccharide (WTNP cells), control virus NP cells, STAT downregulation NP cells, enzyme-linked immunosorbent assay (ELISA), Western blot, and qPCR, respectively. The cell survival rate was detected by flow cytometry and TUNEL staining reverse transcriptase-polymerase chain reaction (qPCR). NP cells were treated with TS IIA and AS IV which had been made into different concentrations, and then, the expression of miR-223, p-STAT1, and p-JAK families was detected by WB Western blotting and qPCR. MiR-223 selectively acts on JAK2/STAT1 pathway, increases the expression of TNF-α, IL-6, MMP-9, MMP-3, caspase3-1, and caspase-3, and induces apoptosis, which can be eliminated by silencing STAT1. TS IIA combined with AS IV could inhibit the expression of miR-223, p-STAT1, and p-JAK2 in NP cells, and they showed a dose-dependent tendency to p-STAT1 and p-JAK2. This study shows that miR-223 promotes the inflammatory response and induces cell injury of NP cells by acting on the JAK2/STAT1 pathway, and the combination of TS IIA and AS IV may protect NP cells by downregulating miR-223 and inhibiting the expression of JAK2 and STAT1.

Transplantation and immunosuppression: a review of novel transplant-related immunosuppressant drugs

Immunosuppressive drugs used in the transplantation period are generally defined as induction and maintenance therapy. The use of immunosuppressants, which are particularly useful and have fewer side effects, decreased both mortality and morbidity. Many drugs such as steroids, calcineurin inhibitors (cyclosporine-A, tacrolimus), antimetabolites (mycophenolate mofetil, azathioprine), and mTOR inhibitors (sirolimus, everolimus) are used as immunosuppressive agents. Although immunosuppressant drugs cause many side effects such as hypertension, infection, and hyperlipidemia, they are the agents that should be used to prevent organ rejection. This shows the importance of individualized drug use. The optimal immunosuppressive therapy post-transplant is not established. Therefore, discovering less toxic but more potent new agents is of great importance, and new experimental and clinical studies are needed in this regard.Our review discussed the mechanism of immunosuppressants, new agents' discovery, and current therapeutic protocols in the transplantation.

Targeting JAK-STAT Signalling Alters PsA Synovial Fibroblast Pro-Inflammatory and Metabolic Function

Objectives

Psoriatic arthritis (PsA) is a chronic inflammatory disease associated with psoriasis. Janus Kinase inhibitors (JAKi) have emerged as an encouraging class of drugs for the treatment of PsA. Here, we compare the effect of four JAKi on primary PsA synovial fibroblasts (PsAFLS) activation, metabolic function, and invasive and migratory capacity.

Methods

Primary PsAFLS were isolated and cultured with JAKi (Peficitinib, Filgotinib, Baricitinib and Upadacitinib) in the presence of Oncostatin M (OSM). pSTAT3 expression in response to OSM was quantified by Western Blot analysis. Pro-inflammatory cytokines/chemokines were quantified by ELISA and cell migration by wound-repair scratch assays. Invasive capacity was examined using Matrigel™ invasion chambers and MMP multiplex MSD assays. PsAFLS bioenergetics was assessed using the Seahorse XF^e Extracellular Flux Analyzer, which simultaneously quantifies two energetic pathways- glycolysis (ECAR) and oxidative phosphorylation (OCR). In parallel, inflammatory, invasive, and migratory genes were quantified by RT-PCR.

Results

OSM induces pSTAT3 expression in PsAFLS. OSM-induced secretion of MCP-1 and IL-6 was inhibited by all JAKi with Peficitinib, Baricitinib and Upadacitinib showing the greatest effect. In contrast, JAKi had no significant impact on IL-8 expression in response to OSM. PsAFLS cell invasion, migratory capacity and MMP1, 3, and 9 were suppressed following JAKi treatment, with Peficitinib showing the greatest effect. These functional effects were accompanied by a change in the cellular bioenergetic profile of PsAFLS, where JAKi significantly decreased glycolysis and the ECAR/OCR, resulting in a shift to a more quiescent phenotype, with Peficitinib demonstrating the most pronounced effect.

Conclusion

This study demonstrates that JAK/STAT signalling mediates the complex interplay between inflammation and cellular metabolism in PsA pathogenesis. This inhibition shows effective suppression of inflammatory mechanisms that drive pathogenic functions of PsAFLS, further supporting the role of JAKi as a therapeutic target for the treatment of PsA.

Working and safety profiles of JAK/STAT signaling inhibitors. Are these small molecules also smart?

The Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway is an important intracellular route through which many different extracellular soluble molecules, by reaching membrane receptors, can signal the nucleus. The spectrum of soluble molecules that use the JAK/STAT pathway through their corresponding receptors is quite large (almost 50 different molecules), and includes some cytokines involved in the pathogenesis of many immune-mediated diseases. Such diseases, when left untreated, present an evident hyperactivation of JAK/STAT signaling. Therefore, given the pathogenetic role of JAK/STAT, drugs known as JAK inhibitors (JAKi), that target one or more JAKs, have been developed to counteract JAK/STAT signal hyperactivation. As some hematological malignancies present an intrinsic JAK/STAT hyperactivation due to a JAK mutation, some JAKi have also been successfully used in this context. Regulatory agencies for drug administration in different countries have already approved a few JAKi in the setting of either immune-mediated diseases or hematological malignancies. Aim of this review is to describe the physiology of intracellular JAK/STAT pathway signaling and the pathological conditions associated to its dysregulation. Then, the rationale for targeting JAK in rheumatic autoimmune diseases is discussed, along with clinical data from registration studies showing the efficacy of these drugs. Finally, the excellent safety profile of JAKi is discussed in the context of the apparent poor specificity of JAK/STAT pathway signal.

Experimental and Investigational Pharmacotherapy for Psoriatic Arthritis: Drugs of the Future

In recent years, different studies have shown in psoriatic arthritis (PsA), the pathogenetic role of multiple cytokines other than tumor necrosis factor-α, such as interleukin-17 (IL-17), and IL-23 and dysfunction of Janus kinase (JAK)-signal family pathway. These molecules also represent the target of recently developed biologic (bDMARDs) and targeted synthetic disease modifying antirheumatic drugs (DMARDs) (tsDMARDs) currently investigated in several Phase II and III randomized controlled trials (RCTs). This review examines the therapeutic efficacy and safety of most recent developed IL-17, IL-23 and JAK inhibitors and highlights how these new PsA therapies are going to revolutionize the management of PsA in the next few years. Ongoing RCTs of these molecules in PsA are also described. Available literature on new anti-IL-17 and anti-IL-23 agents and JAK inhibitors demonstrates the potential role of these molecules as effective therapeutic strategies across multiple PsA clinical domains, along with an acceptable tolerability and safety profile, thus expanding the treatment options available for PsA patients. Of note, other molecules are under investigation, and among those, potential therapeutic strategies seem to be represented by single antibodies blocking simultaneously two cytokines, the agents inhibiting mammalian target of rapamycin (mTOR), receptor retinoic acid receptor-related orphan receptor gamma (RORγt), A3 adenosine receptor (A3 AR), and K⁺ channel voltage channel inhibitors. Remarkable progress has been made in PsA pharmacotherapy, and novel bDMARDs targeting IL17A and tsDMARDs (JAK-inhibitors) represent promising therapies. More clinical trials are needed to better characterize the efficacy and safety profile of these therapeutic agents in PsA treatment.

Patient-Centered Care in Psoriatic Arthritis-A Perspective on Inflammation, Disease Activity, and Psychosocial Factors

Psoriatic arthritis (PsA) is a seronegative spondyloarthropathy characterized by skin lesions, dactylitis, and enthesitis. Patients with PsA suffer from a variety of psychosocial difficulties and nonspecific symptoms early on in the disease course and continue to experience progressive disease due to delays in diagnosis and treatment. Symptoms initially viewed as somatization could lead to undertreatment and promote psychological distress, poor coping, and negative patient-provider relationships. Pain and fatigue are important complaints that affect the patient's perception and may need to be addressed with a multidisciplinary approach. Maladaptive cognitive responses can lead to a negative illness perception and impact patient beliefs and concerns over treatment, as well as nonadherence. An underlying inflammatory component in affective disorders has been examined, though whether and how it may interact mechanistically in PsA warrants interest. Cognitive behavioral therapy represents a nonpharmacological treatment modality that can be combined with cytokine-targeted therapy to address both somatic and psychological complaints. Future directions for research include: (1) Elucidating nonspecific manifestations (e.g., subclinical stage, differential with functional syndromes) of PsA and how they impact diagnosis and management; (2) characterizing immune-mediated components of mood disorders in PsA; and (3) whether a bidirectional approach with abrogating inflammation and psychotherapeutic support leads to improved outcomes.

Psoriatic arthritis: A systematic review of non-HLA genetic studies and important signaling pathways

Psoriatic arthritis (PsA) is a common, chronic inflammatory disease with complex pathogenesis. In recent years, a number of susceptibility non-human leukocyte antigen (HLA) genes of PsA have been revealed, which also act as important factors in the pathogenesis of PsA as well as HLA genes. By searching the databases National Center for Biotechnology Information, Google and PubMed, 37 articles are included and 50 susceptibility non-HLA genes for PsA are presented, such as IL23A, TNIP1, TYK2, STAT4, IL12B, RUNX3 and TRAF3IP2. In these non-HLA genes, some are common genes shared with other diseases, whereas most of these susceptibility genes are related to the pathogenesis of PsA by activation or inhibition of the signaling pathways. Several signaling pathways possibly implicated in the pathogenesis of PsA are introduced in this paper, including the 2 mainly signaling pathways, IL23/Th17 signaling pathway and NF-κB signaling pathway, and the other involved signaling pathways, such as JAK-STAT signaling pathway and MAPK signaling pathway.

A novel treatment for psoriatic arthritis: Janus kinase inhibitors

Psoriatic arthritis (PsA) is a type of chronic inflammatory arthritis which is associated with psoriasis. The early recognition and treatment for PsA are of critical importance. Janus kinase (JAK) inhibitors, as a kind of orally small molecules, have emerged as an encouraging class of drug in PsA treatment. This review provides a discussion of the role and current status of JAK inhibitors in the control of PsA. There are three JAK inhibitors approved for use in autoimmune diseases, for example, tofacitinib, baricitinib, and upadacitinib, and only tofacitinib has been approved in PsA treatment. The clinical trials of upadacitinib and filgotinib in PsA patients are undergoing. The efficacy and safety of these agents were briefly discussed. Although there are still issues in terms of their efficacy and safety currently, JAK inhibitors are expected to benefit more PsA patients in future.

Metabolic Syndrome and psoriatic arthritis: considerations for the clinician

Introduction: Metabolic Syndrome (MetS) is strictly interconnected with systemic inflammation, and increased evidence has described a close link between this condition and Psoriatic Arthritis (PsA).Areas covered: This review summarizes main studies exploring clinical aspects and prevalence of MetS in PsA cohorts. Further, there is accumulating evidence showing shared inflammatory pathways between MetS, its components, and PsA.Expert opinion: The high prevalence of MetS in PsA highlights the need for screening, evaluation, and close monitoring of MetS and its components (namely, diabetes mellitus, obesity, hypertension, and dyslipidemia) in psoriatic patients.Further studies should focus on the pathogenetic link between MetS and PsA. More studies are required to identify appropriate algorithms for the assessment and management of MetS in PsA patients.

Emerging systemic drugs in the treatment of plaque psoriasis

INTRODUCTION

Psoriasis is a common, chronic inflammatory skin condition that affects 2-3% of the US population and represents a large psychosocial burden for patients. Over the last decade, highly effective targeted therapies for psoriasis have been developed - namely, those targeting interleukin (IL)-17 and IL-23. The success of biologic agents targeting IL-17 and IL-23 underscores the importance of the IL-23/T helper (Th)17 cell axis in psoriasis pathogenesis. Oral small molecule drugs - such as Janus kinase (JAK) inhibitors, tyrosine kinase 2 (TYK2) inhibitors, and fumaric acid esters (FAEs) - are also being investigated for the treatment of psoriasis.

AREAS COVERED

This article reviews systemic biologic and oral small molecule drugs currently undergoing clinical trials for the treatment of plaque psoriasis.

EXPERT OPINION

Many patients with psoriasis have mild disease, and many with mild disease do not seek medical care for their condition. Many patients with mild disease could be adequately treated with topical treatments and phototherapy; however, adherence and feasibility have often been an issue with these treatment types. There seems to be limited room for development of novel biologics, as the existing ones are extraordinarily safe, effective, and convenient with few injections. Patients would prefer a safe, effective oral treatment; however, JAK inhibitors seem unlikely to fill this role completely.

Targeted synthetic pharmacotherapy for psoriatic arthritis: state of the art

INTRODUCTION

In recent years, different studies regarding psoriatic arthritis (PsA) have shown the pathogenetic role of dysfunction of signaling pathways involving the phosphodiesterase-4 enzyme and transcription factors or enzymes belonging to the kinase (JAK)-signal family pathway. These also represent the target of several drugs known as targeted synthetic disease-modifying antirheumatic drugs (tsDMARDs).

AREAS COVERED

The authors performed a systematic literature search using the PubMed database, as well as through retrieving data from randomized controlled trials, their post-hoc analysis, and pooled data analysis on the efficacy and safety profile of the PDE4 inhibitor (PDE4i), apremilast, and the inhibitors of JAK (JAKis), tofacitinib, filgotinib, baricitinib, and upadacitinib, in PsA.

EXPERT OPINION

In PsA, the PDE4i, apremilast, and the JAKi, tofacitinib, are effective across multiple clinical domains and have an acceptable tolerability profile, thus expanding the treatment options available for PsA patients. Apremilast and tofacitinib show several advantages mainly represented by their oral administration, a fast onset of action, and a short half-life. Data on tsDMARDs in PsA are still limited, and randomized trials and real-life studies are advocated.

[JAK inhibitors: Perspectives in internal medicine]

In the past ten years, the better understanding of the pathophysiological mechanisms underlying inflammatory and autoimmune diseases has led to the emergence of many targeted therapies. Among them, the Janus kinase inhibitors are acting upstream in the inflammatory cascade of several key cytokines in disorders such as rheumatoid arthritis, ulcerative colitis or psoriasis. At the moment, these three diseases represent the only indications validated by the FDA and the EMA of the use of JAK inhibitors apart from hematology. Preclinical data and therapeutic trials indicate their efficacy in other autoimmune or inflammatory conditions, such as lupus, dermatomyositis, ankylosing spondylitis, sarcoidosis and giant cell arteritis. This review provides a summary of current use and advancement of knowledge in the use of JAK inhibitors in pathologies faced by internists.

A specific small-molecule inhibitor of protein kinase CδI activity improves metabolic dysfunction in human adipocytes from obese individuals

The metabolic consequences and sequelae of obesity promote life-threatening morbidities. PKCδI is an important elicitor of inflammation and apoptosis in adipocytes. Here we report increased PKCδI activation via release of its catalytic domain concurrent with increased expression of proinflammatory cytokines in adipocytes from obese individuals. Using a screening strategy of dual recognition of PKCδI isozymes and a caspase-3 binding site on the PKCδI hinge domain with Schrödinger software and molecular dynamics simulations, we identified NP627, an organic small-molecule inhibitor of PKCδI. Characterization of NP627 by surface plasmon resonance (SPR) revealed that PKCδI and NP627 interact with each other with high affinity and specificity, SPR kinetics revealed that NP627 disrupts caspase-3 binding to PKCδI, and in vitro kinase assays demonstrated that NP627 specifically inhibits PKCδI activity. The SPR results also indicated that NP627 affects macromolecular interactions between protein surfaces. Of note, release of the PKCδI catalytic fragment was sufficient to induce apoptosis and inflammation in adipocytes. NP627 treatment of adipocytes from obese individuals significantly inhibited PKCδI catalytic fragment release, decreased inflammation and apoptosis, and significantly improved mitochondrial metabolism. These results indicate that PKCδI is a robust candidate for targeted interventions to manage obesity-associated chronic inflammatory diseases. We propose that NP627 may also be used in other biological systems to better understand the impact of caspase-3-mediated activation of kinase activity.

Biological and synthetic target DMARDs in psoriatic arthritis

Psoriatic arthritis (PsA) is a chronic multi-faceted immune-mediated systemic disorder, characterized by articular, cutaneous, enthesis, nail and spine involvement. Articular manifestations of PsA are particularly common and highly disabling for patients, while the heterogeneous clinical subsets of the disease are challenging for clinicians. In recent years, research has made many advances in understanding the pathogenesis of the disease from genetic, epigenetic and molecular points of view. New drugs are now available for the treatment of this condition, and, in particular, TNF-alfa inhibitors, historically the first biologicals approved in PsA, are now juxtaposed by new biological disease modifying anti-rheumatic drugs (bDMARDs) with different modes of action. Targeting IL-12/IL-23 p40 common subunit with ustekinumab, IL-17A with secukinumab and ixekizumab, T cells co-stimulation with abatacept, is now possible, safe and effective. Moreover, targeted synthetic molecules with oral administration are available, with the possibility to interfere with phosphodiesterase-4 and JAK/STAT pathways. Indeed, new drugs are under development, with the possibility to target selectively IL-17 receptor, IL-23, and other key molecular targets in the pathogenesis of this condition. In this narrative review, we provide an up-to-date overview of the current application of biological and targeted synthetic DMARDs in the field of PsA, with particular regard to the clinical significance of this possibility to target a higher number of distinct immune-pathways.

Tofacitinib for the treatment of psoriasis and psoriatic arthritis

INTRODUCTION

Psoriasis and psoriatic arthritis (PsA) are inflammatory immune-mediated conditions which can cause considerable disability and reduced quality of life. Management can be complex as clinical heterogeneity may lead to different treatment pathways. Tofacitinib is a novel, oral Janus Kinase (JAK) inhibitor with proven efficacy in rheumatoid arthritis. Areas covered: This review analyzes recent studies of tofacitinib in psoriatic disease treatment. The relevant literature was identified using clinicaltrials.gov, PubMed, and Google Scholar. Tofacitinib efficacy was demonstrated in PsA by the OPAL Broaden and OPAL Beyond phase-III studies, and received FDA and EMA approval. Tofacitinib was superior to placebo for the treatment of moderate-to-severe plaque psoriasis in the OPT Pivotal 1 and 2, OPT Retreatment studies, but FDA approval was declined for this indication based on issues of clinical efficacy and long-term safety. Expert commentary: Tofacitinib is an important oral drug for the treatment of PsA. However, the long-term safety data require further evaluation. Tofacitinib and other JAK inhibitors show potential to broaden the treatment options in PsA and other inflammatory conditions.

IL-17 production by NKG2D-expressing CD56+ T cells in type 2 diabetes

T cells expressing CD56 (identified as CD3+CD56+) play a potential role in activation or regulation of other immune cells by secreting various cytokines. We hypothesized that these cells expressing the natural group 2, member D (NKG2D) could produce high levels of interleukin (IL)-17 in type 2 diabetes (T2D). CD56 + T cells expressing NKG2D of T2D patients, particularly in poor glycemic control (PC) predominantly produced higher IL-17 compared to the NKG2D negative population. IL-17 production of CD56 + T cells with NKG2D + was positively correlated with the level of HbA1c (N = 22, R² = 0.120 and P =  0.044). Interestingly, CD56+ T cells with NKG2D^Hi of T2D patients had significantly higher IL-17 production than those of CD56 + T cells with NKG2D^Low (P =  0.027) and showed statistically significant with P-value < 0.001 compared to CD56 + T cells with NKG2D^Hi of non-diabetic individuals (ND). In summary, CD56 + T cells expressing NKG2D, especially in the NKG2D^Hi population may be involved in pathogenesis and severity of T2D via IL-17.

Switching Between Biological Treatments in Psoriatic Arthritis: A Review of the Evidence

Psoriatic arthritis (PsA) is a chronic inflammatory arthropathy. Therapy with anti-tumor necrosis factor (TNF)-α agents represents the first therapeutic choice for moderate and severe forms; however, PsA patients can experience anti-TNFα failure, lack of efficacy, or adverse events. Several evidences exist on the effectiveness of switching among different TNFα inhibitors, and we reviewed the published data on the effectiveness of anti-TNFα first-, second- and third-line. Most of the studies report that the main reason for switching to a second anti-TNFα agent is represented by lack of efficacy (primary or secondary) and, more rarely, adverse events. Switchers receiving their second anti-TNFα agent have considerably poorer responses compared with non-switchers. Survival of anti-TNFα treatment appears to be superior in PsA patients when compared with rheumatoid arthritis patients. Switching from anti-TNF agents to ustekinumab or secukinumab or apremilast can represent a valid alternative therapeutic strategy.

Small molecule therapy for managing moderate to severe psoriatic arthritis

INTRODUCTION

The majority of psoriatic arthritis (PsA) patients experience a good clinical response to conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and biologic therapies (bDMARDs). However, treatment failure with these drugs can represent a relevant clinical problem. Moreover, in daily clinical practice, the appropriate identification of patients eligible for these agents can be conditioned by numerous aspects, mainly represented by comorbidities, such as history of malignancies, chronic and recurrent infectious diseases. Areas covered: We searched in the PUBMED database and review published data on the efficacy and safety profile of the small molecules, inhibitor of phosphodiesterase 4, apremilast, and of JAK/STAT pathways, tofacitinib, in PsA. Moreover, we report data on the other JAK inhibitor, baricitinib, and the A(3) adenosine receptors agonist, CF101, emerging by studies conducted in psoriasis patients. Expert opinion: In Psoriatic Arthritis, apremilast appears promising for PsA and recent studies have shown a good efficacy and an acceptable safety profile. Data on tofacitinib in PsA are limited. Studies on the small molecules, baricitinib and CF101 are still incomplete and limited to trials conducted in Rheumatoid Arthritis and in psoriasis. Further studies on small molecules and on their underlining mechanisms are advocated in PsA.

Quantitative imaging by pixel-based contrast-enhanced ultrasound reveals a linear relationship between synovial vascular perfusion and the recruitment of pathogenic IL-17A-F+IL-23+ CD161+ CD4+ T helper cells in psoriatic arthritis joints

To develop quantitative imaging biomarkers of synovial tissue perfusion by pixel-based contrast-enhanced ultrasound (CEUS), we studied the relationship between CEUS synovial vascular perfusion and the frequencies of pathogenic T helper (Th)-17 cells in psoriatic arthritis (PsA) joints. Eight consecutive patients with PsA were enrolled in this study. Gray scale CEUS evaluation was performed on the same joint immediately after joint aspiration, by automatic assessment perfusion data, using a new quantification approach of pixel-based analysis and the gamma-variate model. The set of perfusional parameters considered by the time intensity curve includes the maximum value (peak) of the signal intensity curve, the blood volume index or area under the curve, (BVI, AUC) and the contrast mean transit time (MTT). The direct ex vivo analysis of the frequencies of SF IL17A-F⁺CD161⁺IL23⁺ CD4⁺ T cells subsets were quantified by fluorescence-activated cell sorter (FACS). In cross-sectional analyses, when tested for multiple comparison setting, a false discovery rate at 10%, a common pattern of correlations between CEUS Peak, AUC (BVI) and MTT parameters with the IL17A-F⁺IL23⁺ - IL17A-F⁺CD161⁺ - and IL17A-F⁺CD161⁺IL23⁺ CD4⁺ T cells subsets, as well as lack of correlation between both peak and AUC values and both CD4⁺T and CD4⁺IL23⁺ T cells, was observed. The pixel-based CEUS assessment is a truly measure synovial inflammation, as a useful tool to develop quantitative imaging biomarker for monitoring target therapeutics in PsA.

Incidence of Malignancies in a Cohort of Psoriatic Arthritis Patients Taking Traditional Disease Modifying Antirheumatic Drug and Tumor Necrosis Factor Inhibitor Therapy: An Observational Study

Objective.

Psoriatic arthritis (PsA) is an inflammatory arthropathy, associated with skin and/or nail psoriasis. As suggested in 2012 by the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA), studies devoted to assess cancer in the PsA population are still limited and need to be increased. Therefore, the aim of this study was to determine the incidence of malignancies in patients with PsA who are taking conventional and biologic therapies.

Methods.

A cohort of patients with PsA was followed prospectively. At first visit, as well as at each 3–4 month followup visit, according to standardized clinical practice, medical history, and physical and laboratory findings were recorded. Information on the presence of comorbidities, as well as malignancies, was collected. At each visit, data were recorded on radiography and pathology, confirming malignancy diagnosis, when present.

Results.

A total of 618 patients with PsA were included in the study. In particular, 296 were taking anti-tumor necrosis factor-α (anti-TNF) agents and 322 were taking disease-modifying antirheumatic drugs (DMARD). During the observation period, in the total group, 44 patients (7.1%) had a diagnosis of malignancy. Of them, 14 (4.7%; 95% CI 2.8–7.8; 0.52/100 patient-yrs) received anti-TNF therapy and 30 (9.3%; 95% CI 6.6–13.0; 1.03/100 patient-yrs) received traditional DMARD (p = 0.019). However, after adjusting for major demographic and clinical characteristics, the difference between the 2 treatments was no longer significant (p = 0.480), and the only predictor of malignancy occurrence was age (HR 1.04, 95% CI 1.009–1.073, p = 0.012).

Conclusion.

Data from this study confirm that biological therapies do not lead to any increased risk for cancer development, when adequately administered and with proper followup.

Psoriatic arthritis and psoriasis: differential diagnosis

Psoriasis frequency ranges from 1 to 3 % in white population, and arthritis occurs in 10-40 % of psoriasis patients, representing a relevant health issue. Psoriatic arthritis (PsA) is an inflammatory arthropathy, associated with psoriasis, in which ocular-, intestinal-, metabolic-, and cardiovascular-related manifestations can variably coexist. In order to favor early PsA and psoriasis diagnosis, it is crucial to rule out other conditions that can resemble the disease and delay appropriate therapeutic approach. Therefore, the aim of this review is to focus on PsA and psoriasis differential diagnosis.

Aberrant NKG2D expression with IL-17 production of CD4+ T subsets in patients with type 2 diabetes

Type 2 diabetes (T2D) is a systemic inflammatory disease. Although the natural killer group 2, member D (NKG2D) receptor, was not expressed normally on CD4+ T cells, the aberrant expression was found in pathological conditions such as in auto-immune diseases. However, the involvement of NKG2D in pathogenesis of T2D is unclear. We hypothesize that there is an inflammatory CD4+ T cell subpopulation expressing NKG2D and producing interleukin (IL)-17 in T2D. NKG2D expression on CD4+ T cells and their subsets were analyzed by multi-color staining using flow cytometry. Lymphocytes were activated by phorbol-12-myristate-13-acetate (PMA) and ionomycin, and were stained for intracellular IL-17. To investigate the mechanism of IL-17 production, patients' lymphocytes were stimulated using specific anti-T cell receptor (TCR) alone, anti-NKG2D alone or a combination of the two antibodies. CD4+ T cells and particularly, CD4+CD28^nullT subset of T2D patients were highly expressed NKG2D and more prevalent compared to non-diabetic individuals (ND) (P=0.039 and P=0.022, respectively). Significantly higher percentages of CD4+CD28^nullNKG2D+T cells of patients produced IL-17 when compared to those of ND (P=0.024) and were positively correlated with the level of glycated hemoglobin A1c (HbA1c) (R²=0.386, P=0.041). Additionally, this cell population could be stimulated by specific monoclonal anti-NKG2D to produce IL-17. In conclusion, CD4+CD28^nullNKG2D+T cells were expanded in T2D, especially in patients with poor glycemic control. NKG2D may be one of the surrogate co-stimulatory receptors leading to irregular inflammatory function producing IL-17. An IL-17 producing CD4+CD28^nullNKG2D+T cells may potentially be involved in pathogenesis and drive severity of the disease with the glycemic dependence. This particular cell type could be targeted for prognostic or therapeutic purposes.

Emerging drugs for psoriatic arthritis

INTRODUCTION

The majority of Psoriatic Arthritis patients experience a good clinical response to anti-Tumor Necrosis Factor (TNF)-α therapies. However, treatment failure with anti-TNF-α can represent a relevant clinical problem.

AREAS COVERED

We review the efficacy and safety profile of biological therapies that have been reported from randomized, controlled trials in phase II and phase III available in Pubmed Database for agents targeting IL-12/23p40 antibody (ustekinumab) and IL-17 (secukinumab), inhibitor of phosphodiesterase 4, (apremilast), and of JAK/STAT pathways (tofacitinib) and CTLA4 co-stimulation (abatacept) in Psoriatic Arthritis.

EXPERT OPINION

In Psoriatic Arthritis, main emerging drugs are represented by the fully human monoclonal IL-12/23p40 antibody, ustekinumab, the agent targeting IL-17, secukinumab, and the inhibitor of phosphodiesterase 4, apremilast. Results on T cell co-stimulation inhibition by abatacept are insufficient both in psoriasis and in PsA. In vitro investigations on JAK/STAT pathways in PsA suggest that tofacitinib could represent a further valuable therapeutic option. Emerging biological treatments other than anti-TNF agents, ustekinumab, secukinumab and apremilast appear promising for Psoriatic Arthritis and recent studies have showed a good efficacy and an acceptable safety profile; however, further and long-term studies are advocated.

Protein arrays for biomarker discovery in lupus

Lupus is one of the most common autoimmune diseases, yet many mechanisms of its pathogenesis are not fully known. Over the last few years, advances in protein array technology have accelerated rapidly, resulting in many promising insights toward the discovery of novel lupus biomarkers that may become useful in disease diagnosis and management. Still, only two types of analytical protein arrays thus far, being antibody and antigen arrays, have found notable usage toward lupus biomarker discovery. In this review, we summarize current protein array technologies being used for biomarker discoveries in lupus and associated biomarker findings, as well as protein arrays that are likely to be used for lupus biomarker discovery in the near future.

Progress in understanding and utilizing TNF-α inhibition for the treatment of psoriatic arthritis

The improved recognition of pathogenetic molecular mechanisms has led to the use of drugs targeting cytokines in different inflammatory arthropathies as well psoriatic arthritis (PsA). In particular, the progress in knowledge on tumor necrosis factor (TNF)-α in the pathogenesis of PsA has changed the therapeutic approach by use of direct and receptor cytokine antagonists. Currently, infliximab (IFX), adalimumab, etanercept, golimumab and certolizumab pegol represent the five anti-TNF-α available for the treatment of PsA. This review describes evidence on treatment aimed at neutralizing TNF-α in PsA patients, from the first study in 2000 until today, mainly derived from randomized clinical trials. In comparison with traditional therapies, anti-TNF-α agents have shown to have more efficacy both in treating clinical aspects, including enthesitis, dactylitis, joint pain and swelling, axial involvement, nail and skin lesions, and in reducing radiographic progression. Moreover, anti-TNF-α agents have been demonstrated to be reasonably safe in PsA, as confirmed by data derived by different registries.

Pharmacological treatment of spondyloarthritis: exploring the effectiveness of nonsteroidal anti-inflammatory drugs, traditional disease-modifying antirheumatic drugs and biological therapies

Spondyloarthritis represents a heterogeneous group of articular inflammatory diseases that share common genetic, clinical and radiological features. The therapy target of spondyloarthritis relies mainly in improving patients' quality of life, controlling articular inflammation, preventing the structural joints damage and preserving the functional abilities, autonomy and social participation of patients. Among these, traditional disease-modifying antirheumatic drugs have been demonstrated to be effective in the management of peripheral arthritis; moreover, in the last decade, biological therapies have improved the approach to spondyloarthritis. In patients with axial spondyloarthritis, tumor necrosis factor α inhibitors are currently the only effective therapy in patients for whom conventional therapy with nonsteroidal anti-inflammatory drugs has failed. The aim of this review is to summarize the current experience and evidence about the pharmacological approach in spondyloarthritis patients.

Metabolic syndrome and its relationship with the achievement of minimal disease activity state in psoriatic arthritis patients: an observational study

The aim of the study was to evaluate the influence of metabolic syndrome (MetS) on achieving minimal disease activity (MDA) in psoriatic arthritis (PsA) patients treated with anti-tumor necrosis factor (TNF)-α with a follow-up period of 24 months. A cohort of PsA patients was assessed at the University Federico II of Naples and at University of Padova. For the aim of the present study, patients' data were collected at baseline (T0), at 12 months (T1) and at 24 months (T2). Assessment of metabolic and disease activity parameters was performed at each visit. The NCEP-ACT III criteria were used to identify subjects with MetS and the MDA criteria to evaluate the disease activity. On the basis of the exclusion and inclusion criteria, 330 subjects were included in the study; 134 patients (40.7%) were classified as not having MetS and 196 (59.3%) as having MetS. An inverse association was found between presence of metabolic syndrome and the probability of achieving MDA. Univariate analysis indicated that patients with metabolic syndrome were less likely to achieve MDA than patients without metabolic syndrome (OR 0.45, p < 0.001). This inverse association remained statistically significant in the multivariate regression model (OR 0.56, p < 0.001). Metabolic syndrome is associated with a lower probability of achieving MDA in PsA patients in therapy with anti-TNF-α.

Tofacitinib regulates synovial inflammation in psoriatic arthritis, inhibiting STAT activation and induction of negative feedback inhibitors

BACKGROUND

Psoriatic arthritis (PsA) is a chronic inflammatory disease, characterised by synovitis and destruction of articular cartilage/bone. Janus-kinase and signal transducer and activator of transcription (JAK-STAT) signalling pathway is implicated in the pathogenesis of PsA.

OBJECTIVES

To examine the effect of tofacitinib (JAK inhibitor) on proinflammatory mechanisms in PsA.

METHODS

Primary PsA synovial fibroblasts (PsAFLS) and ex vivo PsA synovial explants were cultured with tofacitinib (1 µM). PhosphoSTAT3 (pSTAT3), phosphoSTAT1 (pSTAT1), suppressor of cytokine signaling-3 (SOCS3), protein inhibitor of activated Stat3 (PIAS3) and nuclear factor kappa B cells (NFκBp65) were quantified by western blot. The effect of tofacitinib on PsAFLS migration, invasion, Matrigel network formation and matrix metallopeptidase (MMP)2/9 was quantified by invasion/migration assays and zymography. Interleukin (IL)-6, IL-8, IFN-gamma-inducible protein 10 (IP-10) monocyte chemoattractant protein (MCP)-1, IL-17, IL-10, MMP3 and tissue inhibitor of metalloproteinases 3 (TIMP3) were assessed by ELISA.

RESULTS

Tofacitinib significantly decreased pSTAT3, pSTAT1, NFκBp65 and induced SOCS3 and PIAS3 expression in PsAFLS and synovial explant cultures (p<0.05). Functionally, PsAFLS invasion, network formation and migration were inhibited by tofacitinib (all p<0.05). In PsA explant, tofacitinib significantly decreased spontaneous secretion of IL-6, IL-8, MCP-1, MMP9/MMP2, MMP3 (all p<0.05) and decreased the MMP3/TIMP3 ratio (p<0.05), with no effect observed for IP-10 or IL-10.

CONCLUSIONS

This study further supports JAK-STAT inhibition as a therapeutic target for the treatment of PsA.

Psoriatic arthritis: latest treatments and their place in therapy

Psoriatic arthritis (PsA) is a heterogeneous chronic inflammatory disease that may affect peripheral and axial joints, entheses, skin and nails, and other organs. Treatment with nonsteroidal anti-inflammatory drugs, steroid and disease-modifying antirheumatic drugs had been the backbone of traditional management of PsA for many years. However, improvement in our understanding of immunopathogenesis of PsA has led to new immunomodulatory therapies. Introduction of novel agents has raised the bar for treatment and helped drive research into additional therapeutic options.