Janus kinases in immune cell signaling

Relative effectiveness and safety of interleukin-6 and Janus kinase inhibitors versus adalimumab in patients with rheumatoid arthritis: a network meta-analysis

OBJECTIVE

The relative efficacy and tolerability of interleukin‑6 (IL-6) and Janus kinase (JAK) inhibitor therapies were compared with those of adalimumab in patients with rheumatoid arthritis (RA) and inadequate responses to methotrexate (MTX).

METHODS

We performed a Bayesian network meta-analysis to combine direct and indirect evidence from randomized controlled trials (RCTs) to examine the efficacy and safety of IL‑6 inhibitors, JAK inhibitors, and adalimumab in patients with RA and inadequate responses to MTX.

RESULTS

Seven RCTs, which included 4428 patients (1066 for IL‑6 inhibitors and 3362 for JAK inhibitors), met the inclusion criteria. IL‑6 inhibitors were placed at the top left of the league table diagonal (Odds ratio, OR 1.43; 95% CrI 1.12-1.82) as these were correlated with the most beneficial ACR20 response rate. Conversely, the placebo was placed at the bottom right of the league table diagonal as it was correlated with the least desirable effects. IL‑6 and JAK inhibitors produced a substantial ACR20 response relative to adalimumab. The surface under the cumulative ranking curve (SUCRA) revealed that treatment with IL‑6 inhibitors had the greatest ability to reach the ACR20 response rate (SUCRA = 0.826), followed by treatment with JAK inhibitors (SUCRA = 0.672) and adalimumab (SUCRA = 0.001). The ACR50 and ACR70 rates displayed patterns similar to the ACR20 response rate. With regard to serious adverse events (SAEs), the SUCRA rating likelihood showed that adalimumab was likely to be the best intervention, followed by JAK and IL‑6 inhibitors.

CONCLUSION

Both IL‑6 and JAK inhibitors are more effective than adalimumab and have similar effects in patients with RA and an inadequate response to MTX. Adalimumab is likely to be safer than JAK and IL‑6 inhibitors.

Genome-Wide Identification of lncRNA and mRNA for Diagnosing Type 2 Diabetes in Saudi Arabia

Purpose

According to the World Health Organization, Saudi Arabia ranks seventh worldwide in the number of patients with diabetes mellitus. To our knowledge, no research has addressed the potential of noncoding RNA as a diagnostic and/or management biomarker for patients with type 2 diabetes mellitus (T2DM) living in high-altitude areas. This study aimed to identify molecular biomarkers influencing patients with T2DM living in high-altitude areas by analyzing lncRNA and mRNA.

Patients and Methods

RNA sequencing and bioinformatics analyses were used to identify significantly expressed lncRNAs and mRNAs in T2DM and healthy control groups. Coding potential was analyzed using coding-noncoding indices, the coding potential calculator, and PFAM, and the lncRNA function was predicted using Pearson's correlation. Differentially expressed transcripts between the groups were identified, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed to identify the biological functions of both lncRNAs and mRNAs.

Results

We assembled 1766 lncRNAs in the T2DM group, of which 582 were novel. This study identified three lncRNA target genes (KLF2, CREBBP, and REL) and seven mRNAs (PIK3CD, PIK3R5, IL6R, TYK2, ZAP70, LAMTOR4, and SSH2) significantly enriched in important pathways, playing a role in the progression of T2DM.

Conclusion

To the best of our knowledge, this comprehensive study is the first to explore the applicability of certain lncRNAs as diagnostic or management biomarkers for T2DM in females in Taif City, Saudi Arabia through the genome-wide identification of lncRNA and mRNA profiling using RNA seq and bioinformatics analysis. Our findings could help in the early diagnosis of T2DM and in designing effective therapeutic targets.

Case control study: G-allele of rs4244165 in JAK1 gene correlated with high-level brief psychiatric rating scale in bipolar patients

Bipolar disorder (BD) is a chronic and clinically complex disease, characterized by pathological disturbances in mood and energy. Cytokines can access the brain and their signaling pathways affect brain functions, such as neurotransmitter metabolism, neuroendocrine function, neural/synaptic plasticity, and mood neural circuitry. JAK 1 is the most common phosphorylation protein combined with the tyrosine kinase cytokine receptors; therefore, we investigated the association between the Janus family kinase 1 (JAK1) gene polymorphisms (rs2780895, rs4244165, and rs17127024) and susceptibility to BD. The case study population included 93 patients diagnosed with BD and 112 healthy controls, selected from the central coastal region of Tunisia. Polymerase chain reaction-restriction fragment length polymorphism was used to investigate these 3 JAK1 polymorphisms. We compared the sociodemographic and clinical parameters of 3 genotypes of this single nucleotide polymorphisms rs2780895, rs4244165, and rs17127024 of the JAK1 gene. The frequencies of the 3 genotypes were similar in the patient and control groups. One-way analysis of variance revealed a significant variation in rs4244165. After hospitalization, the average of the brief psychiatric rating scale score was significantly higher for the wild-type GG genotype than that for the double-mutation TT genotype (31.23% vs 22.85%, P = .043). The least significant difference post hoc test also showed a significant difference between the GG and TT genotypes at both hospital admission (P = .001) and after hospitalization (P = .012), with the GG genotype being associated with a higher brief psychiatric rating scale score. Haplotypic analysis revealed that the wild-type haplotype with the highest frequency (46.62%) was CTG. Our results showed no association between the 3 studied positions and bipolar disorder. However, the G-allele of rs4244165 in JAK1 is associated with the highest level of the brief psychiatric rating scale in patients with bipolar disorder. The JAK/signal transducer and activator of transcription pathway is an interesting therapeutic route that requires further investigations. Studying their regulatory regions can provide a clearer picture of all the interactions involved in the regulation of genetic expression in response to treatment.

Transcriptomic Profiling after In Vitro Δ8-THC Exposure Shows Cytoskeletal Remodeling in Trauma-Injured NSC-34 Cell Line

Neuronal cell death is a physiological process that, when uncontrollable, leads to neurodegenerative disorders like spinal cord injury (SCI). SCI represents one of the major causes of trauma and disabilities worldwide for which no effective pharmacological intervention exists. Herein, we observed the beneficial effects of Δ8-Tetrahydrocannabinol (Δ8-THC) during neuronal cell death recovery. We cultured NSC-34 motoneuron cell line performing three different experiments. A traumatic scratch injury was caused in two experiments. One of the scratched was pretreated with Δ8-THC to observe the role of the cannabinoid following the trauma. An experimental control group was neither scratched nor pretreated. All the experiments underwent RNA-seq analysis. The effects of traumatic injury were observed in scratch against control comparison. Comparison of scratch models with or without pretreatment highlighted how Δ8-THC counteracts the traumatic event. Our results shown that Δ8-THC triggers the cytoskeletal remodeling probably due to the activation of the Janus Kinase Signal Transducer and Activator of Transcription (JAK/STAT) signaling pathway and the signaling cascade operated by the Mitogen-Activated Protein (MAP) Kinase signaling pathway. In light of this evidence, Δ8-THC could be a valid pharmacological approach in the treatment of abnormal neuronal cell death occurring in motoneuron cells.

Tofacitinib versus methotrexate as the first-line disease-modifying antirheumatic drugs in the treatment of rheumatoid arthritis: An open-label randomized controlled trial

OBJECTIVE

To compare tofacitinib and methotrexate (MTX) as first-line disease-modifying antirheumatic drugs (DMARDs) for rheumatoid arthritis (RA).

METHODS

This open-label, randomized controlled, parallel-group, 3-month trial randomly assigned 100 RA patients to tofacitinib 10 mg daily (49 patients) or MTX 25 mg subcutaneously weekly (51 patients). The primary end point was low disease activity (LDA) measured with Disease Activity Score-28 with C-reactive protein (DAS28-CRP), and the secondary end point was LDA and remission measured by DAS28-erythrocyte sedimentation rate (ESR), Clinical Disease Activity Index (CDAI), and Simplified Disease Activity Index (SDAI). Health Assessment Questionnaire Disability Index (HAQ-DI) response and mean reduction of core set of outcomes from baseline at 12 weeks were also analyzed as secondary end points. In addition, acute-phase reactants and composite measurements among groups were examined.

RESULTS

LDA in DAS28-CRP was achieved in 17 (34.7%) tofacitinib patients and 18 (35.3%) MTX patients (p = .95). Fourteen (28.6%) and 11 (21.6%) tofacitinib and MTX patients, respectively, achieved LDA by DAS28-ESR (p = .42). Tofacitinib and MTX groups achieved LDA similarly in CDAI (36.7% against 37.3%; p = .96) and SDAI (38.8% vs. 39.2%; p = .96). There was no significant difference in achieving remission between the groups. At 12 weeks, tofacitinib reduced ESR and CRP (p < .05). Composite measures and functional status decreased within groups but not between groups (p > .05). Five (13.51%) tofacitinib patients developed hypertension. MTX caused gastrointestinal problems in 12 (30%) individuals. Two MTX (5%) and two tofacitinib (5.4%) patients had increased liver enzymes and renal impairment, respectively. Tofacitinib had 5.4% infection compared with 5% for MTX.

CONCLUSIONS

As tofacitinib may be more effective than MTX according to previous reports such as the ORAL Start study, high-dose MTX (25 mg/week, subcutaneously) used in this study may be as efficacious as tofacitinib in patients with established RA who were DMARD naive or had not received a therapeutic dose of DMARDs. However, adverse effects differed between groups. Registered on: ClinicalTrials.gov; ID: NCT04464642.

Relative Remission and Low Disease Activity Rates of Tofacitinib, Baricitinib, Upadacitinib, and Filgotinib versus Methotrexate in Patients with Disease-Modifying Antirheumatic Drug-Naive Rheumatoid Arthritis

BACKGROUND

The relative efficacy of Janus kinase (JAK) inhibitors in producing remission and low disease activity (LDA) states remains unknown since there are currently no trials that provide direct comparisons among JAK inhibitors in disease-modifying antirheumatic drug (DMARD)-naive patients with rheumatoid arthritis (RA).

OBJECTIVES

This study aimed to assess the relative remission and LDA rates of tofacitinib, baricitinib, upadacitinib, and filgotinib compared to those of methotrexate (MTX) in DMARD-naive patients with RA.

METHOD

We conducted Bayesian network meta-analysis and included information from direct and indirect comparisons from randomized controlled trials that examined remission (Disease Activity Score in 28 Joints using C-reactive protein level [DAS28-CRP] <2.6) and LDA (DAS28-CRP ≤ 3.2) produced by tofacitinib, baricitinib, upadacitinib, filgotinib monotherapy, and MTX in patients with DMARD-naive RA.

RESULTS

Four randomized controlled trials, comprising 2,185 patients, met the inclusion criteria. This network meta-analysis showed that treatment with tofacitinib, baricitinib, upadacitinib, and filgotinib achieved a significantly higher remission rate than that with MTX (odds ratio [OR] = 4.13, 95% CI = 2.88-6.02; OR = 2.12, 95% CI = 1.17-4.13; OR = 1.95, 95% CI = 1.10-3.50; OR = 1.79, 95% CI = 1.27-3.53). The ranking probability based on the surface under the cumulative ranking curve indicated that upadacitinib 15 mg had the highest probability of achieving remission (SUCRA = 0.985), followed by tofacitinib 5 mg (SUCRA = 0.574), baricitinib 4 mg (SUCRA = 0.506), filgotinib 200 mg (SUCRA = 0.431), and MTX (SUCRA = 0.004). Moreover, treatment with tofacitinib, baricitinib, upadacitinib, and filgotinib achieved significantly higher LDA rate than that with MTX. The ranking probability for LDA was similar to that for remission; upadacitinib 15 mg had the highest probability of achieving LDA, followed by tofacitinib 5 mg, baricitinib 4 mg, filgotinib 200 mg, and MTX.

CONCLUSIONS

Upadacitinib seems to be one of most effective interventions for achieving remission and LDA in DMARD-naive patients with RA based on the comparative analysis, and there are differences in remission and LDA rates induced by different JAK inhibitors.

Computer-Aided Drug Design of Novel Derivatives of 2-Amino-7,9-dihydro-8H-purin-8-one as Potent Pan-Janus JAK3 Inhibitors

Rheumatoid arthritis (RA) remains one of the most prevalent autoimmune diseases worldwide. Janus kinase 3 (JAK3) is an essential enzyme for treating autoimmune diseases, including RA. Molecular modeling techniques play a crucial role in the search for new drugs by reducing time delays. In this study, the 3D-QSAR approach is employed to predict new JAK3 inhibitors. Two robust models, both field-based with R2 = 0.93, R = 0.96, and Q2 = 87, and atom-based with R2 = 0.94, R = 0.97, and Q2 = 86, yielded good results by identifying groups that may readily direct their interaction. A reliable pharmacophore model, DHRRR1, was provided in this work to enable the clear characterization of chemical features, leading to the design of 13 inhibitors with their pIC50 values. The DHRRR1 model yielded a validation result with a ROC value of 0.87. Five promising inhibitors were selected for further study based on an ADMET analysis of their pharmacokinetic properties and covalent docking (CovDock). Compared to the FDA-approved drug tofacitinib, the pharmaceutical features, binding affinity and stability of the inhibitors were analyzed through CovDock, 300 ns molecular dynamics simulations, free energy binding calculations and ADMET predictions. The results show that the inhibitors have strong binding affinity, stability and favorable pharmaceutical properties. The newly predicted molecules, as JAK3 inhibitors for the treatment of RA, are promising candidates for use as drugs.

Recent progress on tyrosine kinase 2 JH2 inhibitors

Tyrosine kinase 2 (TYK2) is a member of the Janus kinase (JAK) family, which can regulate the signaling of multiple pro-inflammatory cytokines, including IL12, IL23 and type I interferon (IFNα/β), and its inhibitors can treat autoimmune diseases caused by the abnormal expression of IL12 and IL23. Interest in TYK2 JH2 inhibitors has increased as a result of safety concerns with JAK inhibitors. This overview introduces TYK2 JH2 inhibitors that are already on the market, including Deucravactinib (BMS-986165), as well as those currently in clinical trials, such as BMS-986202, NDI-034858, and ESK-001.

Delineation of the distinct inflammatory signaling roles of TAK1 and JAK1/3 in the CIA model of rheumatoid arthritis

Rheumatoid arthritis (RA) is a complex autoimmune disease characterized by hyperactive immune cells within the joints, which leads to inflammation, bone degeneration, and chronic pain. For several decades, frontline immunomodulators such as the anti-tumor necrosis factor (TNF) biologics adalimumab (Humira), etanercept (Enbrel), and infliximab (Remicade) have successfully managed disease progression for many patients. However, over time, patients become refractory to these treatments requiring chronic disease to be managed with conventional and more problematic disease modifying antirheumatic drugs such as methotrexate and hydroxychloroquine, and corticosteroids. Due to the large proportion of patients who continue to fail on frontline biologic therapies, there remains an unmet need to derive novel alternative targets with improved efficacy and safety profiles to treat RA. Recent advances in the field have defined novel targets that play important roles in RA pathology, including the Janus activated kinase (JAK) and transforming growth factor beta activated kinase-1 (TAK1). Although three inhibitors of the JAK signaling pathway have been approved for the treatment of moderately to severely active RA in patients who failed on one or more anti-TNFs, at present, no FDA approved TAK1 treatments exist. Our recent discovery of a highly potent and selective, orally bioavailable TAK1 inhibitor has provided insight into the therapeutic potential of this protein kinase as a novel target for RA. Here, we show the distinct cytokine signaling of tofacitnib (Xeljanz; JAK1/3 inhibitor) compared to HS-276 (TAK1 inhibitor) in lipopolysaccharide (LPS) challenged THP-1 cells. Furthermore, in the collagen induced arthritis pre-clinical mouse model of RA, both tofacintib and HS-276 attenuated disease activity score and inflammatory cytokines in the serum. Overall, our results delineate the distinct cytokine signaling of JAK1/3 and TAK1 targeted therapies in vitro and in vivo and suggest that selective TAK1 inhibitors may provide superior therapeutic relief in RA with fewer adverse events.

Ocular Vascular Diseases: From Retinal Immune Privilege to Inflammation

The eye is an immune privileged tissue that insulates the visual system from local and systemic immune provocation to preserve homeostatic functions of highly specialized retinal neural cells. If immune privilege is breached, immune stimuli will invade the eye and subsequently trigger acute inflammatory responses. Local resident microglia become active and release numerous immunological factors to protect the integrity of retinal neural cells. Although acute inflammatory responses are necessary to control and eradicate insults to the eye, chronic inflammation can cause retinal tissue damage and cell dysfunction, leading to ocular disease and vision loss. In this review, we summarized features of immune privilege in the retina and the key inflammatory responses, factors, and intracellular pathways activated when retinal immune privilege fails, as well as a highlight of the recent clinical and research advances in ocular immunity and ocular vascular diseases including retinopathy of prematurity, age-related macular degeneration, and diabetic retinopathy.

Administration of AG490 decreases the senescence of umbilical cord-mesenchymal stem cells and promotes the cytotherapeutic effect in liver fibrosis

The therapeutic potential of umbilical cord-mesenchymal stem cell (UC-MSC) transplantation in liver fibrosis has been highlighted. However, the fate of transplanted MSCs in the fibrotic microenvironment remains unclear. In this study, we aim to uncover the fate of transplanted MSCs and develop targeting strategies that could enhance the therapeutic efficacy of MSC therapy in liver fibrosis. We used human UC-MSCs as the study object. For in vitro experiments, we stimulated UC-MSCs with several fibrotic-related factors (Liver fibrotic Factors, LF), including TGFβ, TNFα and IFNγ for downstream investigations. We co-cultured LF-treated UC-MSCs with hepatic stellate cell line LX-2 to assess the anti-fibrotic effect. We showed that upon LF stimulation, UC-MSCs exhibited reduced anti-fibrotic activity and underwent rapid senescence. Pathway analysis showed that JAK/STAT3 signaling was highly activated upon LF stimulation, which significantly elevated senescence-associated secretory phenotype (SASP) and senescence in UC-MSCs and could be reversed by a specific JAK inhibitor AG490. Moreover, using both carbon tetrachloride (CCl₄) and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induce fibrosis models, we demonstrated that AG490 pretreatment promoted UC-MSCs survival within the fibrotic liver microenvironment and exhibited enhance therapeutic efficacy. Overall, we showed that targeting MSC senescence in vivo through AG490 pretreatment could enhance the anti-fibrotic activities of UC-MSCs.

Janus kinase inhibitors in autoimmune bullous diseases

Autoimmune bullous disease (AIBD) is a severe skin disorder caused by autoantibodies that target intercellular or cell-matrix adhesion proteins. Currently, the preferred treatment for AIBD involves the use of glucocorticoids or traditional immunosuppressants. Additionally, the utilization of biological agents such as rituximab, omalizumab, and dupilumab is on the rise. However, effectively managing AIBD remains a challenge. The Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway has been implicated in various inflammatory diseases. In recent years, a range of drugs known as JAK inhibitors, which target this pathway, have been developed. Several studies have explored the efficacy and safety of JAK inhibitors for treating AIBD. Consequently, this review begins by examining the role of the JAK/STAT pathway in AIBD, summarizing the application of different JAK inhibitors in AIBD treatment, and emphasizing the importance of disease management in treating AIBD with JAK inhibitors. Furthermore, it highlights the need for a better understanding of the JAK/STAT pathway's role in AIBD, as well as the effectiveness and safety of JAK inhibitors for treating this disease.

Outline of Salivary Gland Pathogenesis of Sjögren's Syndrome and Current Therapeutic Approaches

Sjögren's syndrome (SS) is an autoimmune disease characterized by the involvement of exocrine glands such as the salivary and lacrimal glands. The minor salivary glands, from which tissue samples may be obtained, are important for the diagnosis, evaluation of therapeutic efficacy, and genetic analyses of SS. In the onset of SS, autoantigens derived from the salivary glands are recognized by antigen-presenting dendritic cells, leading to the activation of T and B cells, cytokine production, autoantibody production by plasma cells, the formation of ectopic germinal centers, and the destruction of salivary gland epithelial cells. A recent therapeutic approach with immune checkpoint inhibitors for malignant tumors enhances the anti-tumor activity of cytotoxic effector T cells, but also induces SS-like autoimmune disease as an adverse event. In the treatment of xerostomia, muscarinic agonists and salivary gland duct cleansing procedure, as well as sialendoscopy, are expected to ameliorate symptoms. Clinical trials on biological therapy to attenuate the hyperresponsiveness of B cells in SS patients with systemic organ involvement have progressed. The efficacy of treatment with mesenchymal stem cells and chimeric antigen receptor T cells for SS has also been investigated. In this review, we will provide an overview of the pathogenesis of salivary gland lesions and recent trends in therapeutic approaches for SS.

Chronic graft-versus-host disease in pediatric patients: Differences and challenges

Despite the use of high-resolution molecular techniques for tissue typing, chronic graft-versus-host disease (cGVHD) remains a major complication following allogeneic hematopoietic stem cell transplant. cGVHD adversely affects the life-expectancy and quality of life. The latter is particularly important and functionally relevant in pediatric patients who have a longer life-expectancy than adults. Current laboratory evidence suggests that there is not any difference in the pathophysiology of cGVHD between adults and pediatric patients. However, there are some clinical features and complications of the disease that are different in pediatric patients. There are also challenges in the development of new therapeutics for this group of patients. In this review, we will discuss the epidemiology, pathophysiology, clinical features and consequences of the disease, and highlight the differences between pediatric and adult patients. We will examine the current treatment options for pediatric patients with moderate to severe cGVHD and discuss the challenges facing therapeutic development for cGVHD in the pediatric population.

Janus kinase inhibitor-Tofacitinib associated with pemphigus: an analysis of the FDA adverse event reporting system data

OBJECTIVES

To establish the association between the therapy of Janus kinase inhibitors and the adverse event of pemphigus in patients with rheumatologic and inflammatory disorders.

METHODS

A disproportionality analysis using multi-item gamma Poisson shrinker was conducted to identify signals between medication and adverse events within the FDA Adverse Event Reporting System.

RESULTS

The spontaneous reporting system contained 3,032 pemphigus reports associated with two Janus kinase inhibitors, namely Tofacitinib and Upadacitinib. The year/reporter/geographic area/country/age/sex/indication with the highest number of cases were the year of 2021, physician, North America, Canada, age between 40-49, female and rheumatoid arthritis, respectively. A significant signal was detected in the Tofacitinib group.

CONCLUSION

Pemphigus, a rare and potentially fatal adverse event, was found to occur more frequently in patients receiving Tofacitinib. High-risk individuals were identified as female, age between 40-49, or with rheumatoid arthritis. Medication, adverse events, and underlying disease conditions were identified as potential contributing factors. Rheumatology and dermatology specialists should exercise increased vigilance in clinical practice.

Spondyloarthritis with inflammatory bowel disease: the latest on biologic and targeted therapies

Spondyloarthritis (SpA) encompasses a heterogeneous group of chronic inflammatory diseases that can affect both axial and peripheral joints, tendons and entheses. Among the extra-articular manifestations, inflammatory bowel disease (IBD) is associated with considerable morbidity and effects on quality of life. In everyday clinical practice, treatment of these conditions requires a close collaboration between gastroenterologists and rheumatologists to enable early detection of joint and intestinal manifestations during follow-up and to choose the most effective therapeutic regimen, implementing precision medicine for each patient's subtype of SpA and IBD. The biggest issue in this field is the dearth of drugs that are approved for both diseases, as only TNF inhibitors are currently approved for the treatment of full-spectrum SpA-IBD. Janus tyrosine kinase inhibitors are among the most promising drugs for the treatment of peripheral and axial SpA, as well as for intestinal manifestations. Other therapies such as inhibitors of IL-23 and IL-17, phosphodiesterase 4 inhibitor, α4β7 integrin blockers and faecal microbiota transplantation seem to only be able to control some disease domains, or require further studies. Given the growing interest in the development of novel drugs to treat both conditions, it is important to understand the current state of the art and the unmet needs in the management of SpA-IBD.

NLRP3 Inflammasome as a Potential Therapeutic Target in Dry Eye Disease

Dry eye disease (DED) is a multifactorial ocular surface disorder arising from numerous interrelated underlying pathologies that trigger a self-perpetuating cycle of instability, hyperosmolarity, and ocular surface damage. Associated ocular discomfort and visual disturbance contribute negatively to quality of life. Ocular surface inflammation has been increasingly recognised as playing a key role in the pathophysiology of chronic DED. Current readily available anti-inflammatory agents successfully relieve symptoms, but often without addressing the underlying pathophysiological mechanism. The NOD-like receptor protein-3 (NLRP3) inflammasome pathway has recently been implicated as a key driver of ocular surface inflammation, as reported in pre-clinical and clinical studies of DED. This review discusses the intimate relationship between DED and inflammation, highlights the involvement of the inflammasome in the development of DED, describes existing anti-inflammatory therapies and their limitations, and evaluates the potential of the inflammasome in the context of the existing anti-inflammatory therapeutic landscape as a therapeutic target for effective treatment of the disease.

Efficacy and safety of Janus kinase inhibitors in axial spondyloarthritis

Skin manifestations are common in axial spondyloarthritis (axSpA) and may precede axial involvement. Multidisciplinary management of patients with spondyloarthritis (SpA) is essential. Combined dermatology-rheumatology clinics are established for early recognition of the disease, comorbidities and a comprehensive treatment approach. Treatment options for axSpA are limited because conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and glucocorticoids are ineffective for axial symptoms. Janus kinase inhibitors (JAKi) are targeted synthetic disease-modifying antirheumatic drugs (tsDMARDs) that decrease transduction signalling to the nucleus, resulting in a reduced inflammatory response. Currently, tofacitinib and upadacitinib are approved for treating axSpA in patients with inadequate response to TNF inhibitors (TNFi). Upadacitinib has shown efficacy in non-radiographic axSpA (nr-axSpA), suggesting that JAKi are efficacious across the spectrum of axSpA. The availability of JAKi has opened more options for patients with active axSpA based on the efficacy data and the ease of administration.

Recent advances in the treatment of IBD: Targets, mechanisms and related therapies

Inflammatory bowel disease (IBD), as a representative inflammatory disease, currently has multiple effective treatment options available and new therapeutic strategies are being actively explored to further increase the treatment options for patients with IBD. Furthermore, biologic agents and small molecule drugs developed for ulcerative colitis (UC) and Crohn's disease (CD) have evolved toward fewer side effects and more accurate targeting. Novel inhibitors that target cytokines (such as IL-12/23 inhibitors, PDE4 inhibitors), integrins (such as integrin inhibitors), cytokine signaling pathways (such as JAK inhibitors, SMAD7 blocker) and cell signaling receptors (such as S1P receptor modulator) have become the preferred treatment choice for many IBD patients. Conventional therapies such as 5-aminosalicylic acid, corticosteroids, immunomodulators and anti-tumor necrosis factor agents continue to demonstrate therapeutic efficacy, particularly in combination with drug therapy. This review integrates research from chemical, biological and adjuvant therapies to evaluate current and future IBD therapies, highlighting the mechanism of action of each therapy and emphasizing the potential of development prospects.

Wildfire-related smoke inhalation worsens cardiovascular risk in sleep disrupted rats

Introduction

As a lifestyle factor, poor sleep status is associated with increased cardiovascular morbidity and mortality and may be influenced by environmental stressors, including air pollution.

Methods

To determine whether exposure to air pollution modified cardiovascular effects of sleep disruption, we evaluated the effects of single or repeated (twice/wk for 4 wks) inhalation exposure to eucalyptus wood smoke (ES; 964 μg/m3 for 1 h), a key wildland fire air pollution source, on mild sleep loss in the form of gentle handling in rats. Blood pressure (BP) radiotelemetry and echocardiography were evaluated along with assessments of lung and systemic inflammation, cardiac and hypothalamic gene expression, and heart rate variability (HRV), a measure of cardiac autonomic tone.

Results and Discussion

GH alone disrupted sleep, as evidenced by active period-like locomotor activity, and increases in BP, heart rate (HR), and hypothalamic expression of the circadian gene Per2. A single bout of sleep disruption and ES, but neither alone, increased HR and BP as rats transitioned into their active period, a period aligned with a critical early morning window for stroke risk in humans. These responses were immediately preceded by reduced HRV, indicating increased cardiac sympathetic tone. In addition, only sleep disrupted rats exposed to ES had increased HR and BP during the final sleep disruption period. These rats also had increased cardiac output and cardiac expression of genes related to adrenergic function, and regulation of vasoconstriction and systemic blood pressure one day after final ES exposure. There was little evidence of lung or systemic inflammation, except for increases in serum LDL cholesterol and alanine aminotransferase. These results suggest that inhaled air pollution increases sleep perturbation-related cardiovascular risk, potentially in part by increased sympathetic activity.

Glycolaldehyde-derived advanced glycation end products promote macrophage proliferation via the JAK-STAT signaling pathway

BACKGROUND

Advanced glycation end products (AGEs) are heterogeneous proinflammatory molecules produced by a non-enzymatic glycation reaction between reducing sugars (and their metabolites) and biomolecules with amino groups, such as proteins. Although increases in and the accumulation of AGEs have been implicated in the onset and exacerbation of lifestyle- or age-related diseases, including diabetes, their physiological functions have not yet been elucidated in detail.

METHODS AND RESULTS

The present study investigated the cellular responses of the macrophage cell line RAW264.7 stimulated by glycolaldehyde-derived AGEs (Glycol-AGEs) known as representative toxic AGEs. The results obtained showed that Glycol-AGEs significantly promoted the proliferation of RAW264.7 cells at a low concentration range (1-10 µg/mL) in a concentration-dependent manner. On the other hand, neither TNF-α production nor cytotoxicity were induced by the same concentrations of Glycol-AGEs. The increases observed in cell proliferation by low concentrations of Glycol-AGEs were also detected in receptor triple knockout (RAGE-TLR4-TLR2 KO) cells as well as in wild-type cells. Increases in cell proliferation were not affected by various kinase inhibitors, including MAP kinase inhibitors, but were significantly suppressed by JAK2 and STAT5 inhibitors. In addition, the expression of some cell cycle-related genes was up-regulated by the stimulation with Glycol-AGEs.

CONCLUSIONS

These results suggest a novel physiological role for AGEs in the promotion of cell proliferation via the JAK-STAT pathway.

Inflammation inhibitory activity of green tea, soybean, and guava extracts during Sars-Cov-2 infection through TNF protein in cytokine storm

Coronavirus disease is caused by the pathogen severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) known as COVID-19. COVID-19 has caused the deaths of 6,541,936 people worldwide as of September 27th, 2022. SARS-CoV-2 severity is determined by a cytokine storm condition, in which the innate immune system creates an unregulated and excessive production of pro-inflammatory such IL-1, IL-6, NF Kappa B, and TNF alpha signaling molecules known as cytokines. The patient died due to respiratory organ failure and an acute complication because of the hyper-inflammation phenomenon. Green tea, soybean, and guava bioactive substances are well-known to act as anti-inflammation, and antioxidants become prospective COVID-19 illness candidates to overcome the cytokine storm. Our research aims to discover the bioactivity, bioavailability, and protein targets of green tea, soybean, and guava bioactive compounds as anti-inflammatory agents via the TNF inhibition pathway. The experiment uses in silico methods and harnesses the accessible datasets. Samples of 3D structure and SMILE identity of bioactive compounds were retrieved from the KNApSAck and Dr Duke databases. The QSAR analysis was done by WAY2DRUG web server, while the ADME prediction was performed using SWISSADME web server, following the Lipinsky rules of drugs. The target protein and protein-protein interaction were analyzed using STRING DB and Cytoscape software. Lastly, molecular docking was performed using Autodock 4.2 and visualization with BioVia Discovery Studio 2019. The identified study showed the potential of green tea, soybean, and guava's bioactive compounds have played an important role as anti-inflammation agents through TNF inhibitor pathway.

Juvenile idiopathic arthritis-associated genetic loci exhibit spatially constrained gene regulatory effects across multiple tissues and immune cell types

Juvenile idiopathic arthritis (JIA) is an autoimmune, inflammatory joint disease with complex genetic etiology. Previous GWAS have found many genetic loci associated with JIA. However, the biological mechanism behind JIA remains unknown mainly because most risk loci are located in non-coding genetic regions. Interestingly, increasing evidence has found that regulatory elements in the non-coding regions can regulate the expression of distant target genes through spatial (physical) interactions. Here, we used information on the 3D genome organization (Hi-C data) to identify target genes that physically interact with SNPs within JIA risk loci. Subsequent analysis of these SNP-gene pairs using data from tissue and immune cell type-specific expression quantitative trait loci (eQTL) databases allowed the identification of risk loci that regulate the expression of their target genes. In total, we identified 59 JIA-risk loci that regulate the expression of 210 target genes across diverse tissues and immune cell types. Functional annotation of spatial eQTLs within JIA risk loci identified significant overlap with gene regulatory elements (i.e., enhancers and transcription factor binding sites). We found target genes involved in immune-related pathways such as antigen processing and presentation (e.g., ERAP2, HLA class I and II), the release of pro-inflammatory cytokines (e.g., LTBR, TYK2), proliferation and differentiation of specific immune cell types (e.g., AURKA in Th17 cells), and genes involved in physiological mechanisms related to pathological joint inflammation (e.g., LRG1 in arteries). Notably, many of the tissues where JIA-risk loci act as spatial eQTLs are not classically considered central to JIA pathology. Overall, our findings highlight the potential tissue and immune cell type-specific regulatory changes contributing to JIA pathogenesis. Future integration of our data with clinical studies can contribute to the development of improved JIA therapy.

New small molecules in dermatology: for the autoimmunity, inflammation and beyond

OBJECTIVE AND DESIGN

The discovery of new inflammatory pathways and the mechanism of action of inflammatory, autoimmune, genetic, and neoplastic diseases led to the development of immunologically driven drugs. We aimed to perform a narrative review regarding the rising of a new class of drugs capable of blocking important and specific intracellular signals in the maintenance of these pathologies: the small molecules.

MATERIALS/METHODS

A total of 114 scientific papers were enrolled in this narrative review.

RESULTS

We describe in detail the families of protein kinases-Janus Kinase (JAK), Src kinase, Syk tyrosine kinase, Mitogen-Activated Protein Kinase (MAPK), and Bruton Tyrosine Kinase (BTK)-their physiologic function and new drugs that block these pathways of intracellular signaling. We also detail the involved cytokines and the main metabolic and clinical implications of these new medications in the field of dermatology.

CONCLUSIONS

Despite having lower specificity compared to specific immunobiological therapies, these new drugs are effective in a wide variety of dermatological diseases, especially diseases that had few therapeutic options, such as psoriasis, psoriatic arthritis, atopic dermatitis, alopecia areata, and vitiligo.

Allelic burden of Janus kinase 2 in a 6-month course of therapy for myeloproliferative neoplasms

BACKGROUND

Janus kinase 2 (JAK2) V617F gene mutation is an important marker for the diagnosis of Philadelphia negative Myeloproliferative neoplasms (MPN) which is subdivided into Polycythemia Vera (PV), Primary Myelofibrosis (PMF), and Essential Thrombocythemia (ET). The aim here is to investigate the JAK2 allele burden of the patients diagnosed with the subgroups of MPN and to demonstrate the alterations of hematological parameters and spleen size between diagnosis and 6 months of treatment.

METHODS

A total of 107 patients with the diagnosis of MPN and negative Philadelphia chromosome, 51 males and 56 females with a mean age of 59,74 ± 16,41 years, were included in the study. Diagnosis of MPN was based on the World Health Organization (WHO) criteria. Subgroups of MPN distributed as 49,5% ET, 46,7% PV, and 3,8% PMF. Findings such as the age of the patients, JAK-2 allele burden, and laboratory findings of splenomegaly were examined at the time of diagnosis, 3rd month, and 6th month. JAK2 allele burden and spleen size were re-evaluated in 6th month.

RESULTS

Our study confirmed the findings of high Hb, HCT, and RBC but low platelet values in PV patients with high JAK2 allele burden with respect to other groups, a positive correlation between JAK2 allele burden and LDH.

CONCLUSIONS

A novel finding of our study is, that there is not any reducing effect of the phlebotomy on JAK2 allele burden in PV patients whether they receive phlebotomy or not. Evaluation of the spleen size alteration during 6 months within the subgroups demonstrated a decrease in PV and ET groups whereas no statistically significant difference was found in the PMF group.

Delayed and limited administration of the JAKinib tofacitinib mitigates chronic DSS-induced colitis

In inflammatory bowel disease, dysregulated T cells express pro-inflammatory cytokines. Using a chronic azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colitis model resembling ulcerative colitis, we evaluated whether and when treatment with the Janus kinase (JAK) inhibitor tofacitinib could be curative. Comparing the treatment with two and three cycles of tofacitinib medication in drinking water - intermittently with DSS induction - revealed that two cycles were not only sufficient but also superior over the 3-x regimen. The two cycles of the 2-x protocol paralleled the second and third cycles of the longer protocol. T cells were less able to express interferon gamma (IFN-γ) and the serum levels of IFN-γ, interleukin (IL)-2, IL-6, IL-17, and tumor necrosis factor (TNF) were significantly reduced in sera, while those of IL-10 and IL-22 increased under the 2-x protocol. Likewise, the frequency and effector phenotype of regulatory T cells (Tregs) increased. This was accompanied by normal weight gain, controlled clinical scores, and restored stool consistency. The general and histologic appearance of the colons revealed healing and tissue intactness. Importantly, two phases of tofacitinib medication completely prevented AOM-incited pseudopolyps and the hyper-proliferation of epithelia, which was in contrast to the 3-x regimen. This implies that the initial IBD-induced cytokine expression is not necessarily harmful as long as inflammatory signaling can later be suppressed and that time-restricted treatment allows for anti-inflammatory and tissue-healing cytokine activities.

Identification of Pinosylvin in Pinus nigra subsp. laricio: A Naturally Occurring Stilbenoid Suppressing LPS-Induced Expression of Pro-Inflammatory Cytokines and Mediators and Inhibiting the JAK/STAT Signaling Pathway

Stilbenoids, a group of phytoalexin polyphenols produced by plants as a defence mechanism in response to stress conditions, are known for their anti-inflammatory potential. Pinosylvin, a naturally occurring molecule traditionally found in pinus trees, was here identified in Pinus nigra subsp. laricio var. calabrica from Southern Italy through HPLC analysis. Both this molecule and its well-known analogue resveratrol, the most famous wine polyphenol, were compared for their in vitro potential anti-inflammatory activity. Pinosylvin significantly inhibited the release of pro-inflammatory cytokines (TNF-α and IL-6) and NO mediator in LPS-stimulated RAW 264.7 cells. Moreover, its ability to inhibit the JAK/STAT signaling pathway was assessed: Western blot analyses showed a downregulation of both phosphorylated JAK2 and STAT3 proteins. Finally, in order to verify whether this biological activity could be attributed to a direct interaction of pinosylvin with JAK2, a molecular docking study was performed, confirming the capability of pinosylvin to bind the active site of the protein.

An integrated network pharmacology approach reveals that Darutigenol reduces inflammation and cartilage degradation in a mouse collagen-induced arthritis model by inhibiting the JAK-STAT3 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Darutigenol (DL) is a natural active product derived from the Chinese herbal medicine Sigesbeckia glabrescens (Makino) Makino. It is administered as a traditional Chinese medicine (TCM) to dispel rheumatism, benefit the joints, and detoxify. However, its potential mechanism in the treatment of rheumatoid arthritis (RA) remains unknown.

AIMS OF THE STUDY

The objectives of this research were to determine the effects and elucidate the modes of action of DL on RA-related joint inflammation.

MATERIALS AND METHODS

Network pharmacology and molecular docking were used to screen and validate candidate DL targets for RA treatment, respectively. A DBA/1 mouse rheumatoid arthritis model was induced with bovine type II collagen. Intragastric DL administration was followed by the calculation of the clinical arthritis index. A section of the ankle joint was excised and stained and the pathological changes in it were observed. Enzyme-linked immunosorbent assays (ELISA) and western blotting (WB) were used to clarify the mechanisms of DL in RA treatment.

RESULTS

DL effectively attenuated the inflammation, mitigated the articular cartilage degradation, and bone erosion, and alleviated the inflammatory joints associated with RA. Network pharmacology screened six key targets of DL while molecular docking revealed that it docked well with its protein targets. The DL treatment group presented with significantly less ankle joint redness and swelling, a lower arthritis index scores and serum and bone marrow supernatant IL-6 levels, more complete ankle joint surfaces, and less synovial inflammation, cartilage degradation, and bone erosion than the collagen-induced arthritis (CIA) group. The DL treatment also substantially downregulated the Janus kinase (JAK)1, JAK3, matrix metalloproteinase (MMP)2, MMP9, and phospho-signal transducer and activator of transcription (p-STAT)3 proteins in the joints.

CONCLUSIONS

To the best of our knowledge, the present work was the first to demonstrate that DL has significant anti-inflammatory efficacy and reduces cartilage degradation and bone erosion. It also demonstrated that the anti-RA effect of DL may be explained by its ability to inhibit joint inflammation and reduce articular cartilage degradation through the interleukin (IL)-6/JAK1,3/STAT3 axis and downregulate MMP2 and MMP9. Hence, DL might play a therapeutic role in a mouse RA model.

Hidradenitis Suppurativa and JAK Inhibitors: A Review of the Published Literature

Background: Hidradenitis suppurativa (HS), also known as acne inversa or Verneuil's disease, is a chronic, inflammatory, recurrent, and debilitating skin disease of the hair follicles characterized by inflammatory, painful, deep-rooted lesions in the areas of the body characterized by the presence of the apocrine glands. Unfortunately, huge unmet needs still remain for its treatment. Objective: The purpose of our review was collecting all cases, case series, trials, and ongoing studies available in the literature on the use of this class of drugs for HS. Materials and Methods: The investigated manuscripts included trials, reviews, letters to the editor, real-life studies, case series, and reports. Manuscripts were identified, screened, and extracted for the relevant data following the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. Results: We selected 56 articles of which 25 met the selection criteria for our review. Among the JAK inhibitors to date, there is only one published clinical trial in the literature (Janus kinase 1 inhibitor INCB054707), a real-life study with 15 patients up to week 24 in which upadacitinib was used and a case series where tofacitinib was successfully used. Conversely, there are several ongoing clinical trials. Conclusions: Results to date in the literature show promising levels of efficacy and the safety of JAK inhibitors in HS. Several clinical trials are underway from which it will be very important to compare the available data. There are still too few studies conducted with a low sample size, so it remains critical to investigate this issue further in the future with a real-life study involving a large sample of patients in order to provide safe and viable therapeutic alternatives for HS.

The Use of JAK/STAT Inhibitors in Chronic Inflammatory Disorders

The Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway plays a critical role in orchestrating immune and inflammatory responses, and it is essential for a wide range of cellular processes, including differentiation, cell growth, and apoptosis. Over the years, this pathway has been heavily investigated due to its key role in the pathogeneses of several chronic inflammatory conditions, e.g., psoriasis, atopic dermatitis (AD), and inflammatory bowel diseases (IBDs). Nevertheless, the impact of this pathway on the pathogenesis of inflammatory conditions remains unclear. This review describes the role of the JAK/STAT signaling pathway in the pathogenesis of inflammatory diseases such as psoriasis (Pso), psoriatic arthritis (PsA), AD, and IBD with a focus on ulcerative colitis (UC) and briefly resumes the use of JAK inhibitors in their clinical management.

Selectivity and Ranking of Tight-Binding JAK-STAT Inhibitors Using Markovian Milestoning with Voronoi Tessellations

Janus kinases (JAK), a group of proteins in the nonreceptor tyrosine kinase (NRTKs) family, play a crucial role in growth, survival, and angiogenesis. They are activated by cytokines through the Janus kinase-signal transducer and activator of a transcription (JAK-STAT) signaling pathway. JAK-STAT signaling pathways have significant roles in the regulation of cell division, apoptosis, and immunity. Identification of the V617F mutation in the Janus homology 2 (JH2) domain of JAK2 leading to myeloproliferative disorders has stimulated great interest in the drug discovery community to develop JAK2-specific inhibitors. However, such inhibitors should be selective toward JAK2 over other JAKs and display an extended residence time. Recently, novel JAK2/STAT5 axis inhibitors (N-(1H-pyrazol-3-yl)pyrimidin-2-amino derivatives) have displayed extended residence times (hours or longer) on target and adequate selectivity excluding JAK3. To facilitate a deeper understanding of the kinase-inhibitor interactions and advance the development of such inhibitors, we utilize a multiscale Markovian milestoning with Voronoi tessellations (MMVT) approach within the Simulation-Enabled Estimation of Kinetic Rates v.2 (SEEKR2) program to rank order these inhibitors based on their kinetic properties and further explain the selectivity of JAK2 inhibitors over JAK3. Our approach investigates the kinetic and thermodynamic properties of JAK-inhibitor complexes in a user-friendly, fast, efficient, and accurate manner compared to other brute force and hybrid-enhanced sampling approaches.

JAK1 Pseudokinase V666G Mutant Dominantly Impairs JAK3 Phosphorylation and IL-2 Signaling

Overactive Janus kinases (JAKs) are known to drive leukemia, making them well-suited targets for treatment. We sought to identify new JAK-activating mutations and instead found a JAK1-inactivating pseudokinase mutation, V666G. In contrast to other pseudokinase mutations that canonically lead to an active kinase, the JAK1 V666G mutation led to under-activation seen by reduced phosphorylation. To understand the functional role of JAK1 V666G in modifying kinase activity we investigated its influence on other JAK kinases and within the Interleukin-2 pathway. JAK1 V666G not only inhibited its own activity, but its presence could inhibit other JAK kinases. These findings provide new insights into the potential of JAK1 pseudokinase to modulate its own activity, as well as of other JAK kinases. Thus, the features of the JAK1 V666 region in modifying JAK kinases can be exploited to allosterically inhibit overactive JAKs.

Short interfering RNA in colorectal cancer: is it wise to shoot the messenger?

Colorectal cancer (CRC) is the third most common cancer and the leading cause of gastrointestinal cancer death. 90% of people diagnosed with colorectal cancer are over the age of 50; nevertheless, the illness is more aggressive among those detected at a younger age. Chemotherapy-based treatment has several adverse effects on both normal and malignant cells. The primary signaling pathways implicated in the advancement of CRC include hedgehog (Hh), janus kinase and signal transducer and activator of transcription (JAK/STAT), Wingless-related integration site (Wnt)/β-catenin, transforming growth factor-β (TNF-β), epidermal growth factor receptor (EGFR)/Mitogen-activated protein kinases (MAPK), phosphoinositide 3-kinase (PI3K), nuclear factor kappa B (NF-κB), and Notch. Loss of heterozygosity in tumor suppressor genes like adenomatous polyposis coli, as well as mutation or deletion of genes like p53 and Kirsten rat sarcoma viral oncogene (KRAS), are all responsible for the occurrence of CRC. Novel therapeutic targets linked to these signal-transduction cascades have been identified as a consequence of advances in small interfering RNA (siRNA) treatments. This study focuses on many innovative siRNA therapies and methodologies for delivering siRNA therapeutics to the malignant site safely and effectively for the treatment of CRC. Treatment of CRC using siRNA-associated nanoparticles (NPs) may inhibit the activity of oncogenes and MDR-related genes by targeting a range of signaling mechanisms. This study summarizes several siRNAs targeting signaling molecules, as well as the therapeutic approaches that might be employed to treat CRC in the future.

Role of Innate Interferon Responses at the Ocular Surface in Herpes Simplex Virus-1-Induced Herpetic Stromal Keratitis

Herpes simplex virus type 1 (HSV-1) is a highly successful pathogen that primarily infects epithelial cells of the orofacial mucosa. After initial lytic replication, HSV-1 enters sensory neurons and undergoes lifelong latency in the trigeminal ganglion (TG). Reactivation from latency occurs throughout the host's life and is more common in people with a compromised immune system. HSV-1 causes various diseases depending on the site of lytic HSV-1 replication. These include herpes labialis, herpetic stromal keratitis (HSK), meningitis, and herpes simplex encephalitis (HSE). HSK is an immunopathological condition and is usually the consequence of HSV-1 reactivation, anterograde transport to the corneal surface, lytic replication in the epithelial cells, and activation of the host's innate and adaptive immune responses in the cornea. HSV-1 is recognized by cell surface, endosomal, and cytoplasmic pattern recognition receptors (PRRs) and activates innate immune responses that include interferons (IFNs), chemokine and cytokine production, as well as the recruitment of inflammatory cells to the site of replication. In the cornea, HSV-1 replication promotes type I (IFN-α/β) and type III (IFN-λ) IFN production. This review summarizes our current understanding of HSV-1 recognition by PRRs and innate IFN-mediated antiviral immunity during HSV-1 infection of the cornea. We also discuss the immunopathogenesis of HSK, current HSK therapeutics and challenges, proposed experimental approaches, and benefits of promoting local IFN-λ responses.

Pruritogenic Mediators and New Antipruritic Drugs in Atopic Dermatitis

Atopic dermatitis (AD) is a common highly pruritic chronic inflammatory skin disorder affecting 5-20% of children worldwide, while the prevalence in adults varies from 7 to 10%. Patients with AD experience intense pruritus that could lead to sleep disturbance and impaired quality of life. Here, we analyze the pathophysiology of itchiness in AD. We extensively review the histamine-dependent and histamine-independent pruritogens. Several receptors, substance P, secreted molecules, chemokines, and cytokines are involved as mediators in chronic itch. We also, summarize the new emerging antipruritic drugs in atopic dermatitis.

Tofacitinib fails to prevent T cell transfer colitis in mice but ameliorates disease activity

Tofactinib is a JAK inhibitor approved for ulcerative colitis in humans. Despite of its' proven effectiveness in humans, mechanistic data are scarce on the effectiveness of Tofactinib in experimental colitis in mice. We induced experimental colitis by transfer of CD4+CD25- isolated T cells into RAG2-/- (T and B cell deficient) mice and treated these mice with tofacitinib for 5-6 weeks either with a dosage of 10 or 40 mg/kg body weight immediately after CD4+ transfer or started treatment after first symptoms of disease for several weeks. While treatment with tofacitinib immediately after transfer resulted in an enhanced expansion of CD4+ T cells and did not prevent occurrence of colitis, treatment after start of symptoms of colitis ameliorated disease activity on a clinical basis and in histological analyses. Tofacitinib is effective in the treatment of murine experimental T cell transfer colitis, however does not prevent occurrence of disease.

JAK inhibitors: A new dawn for oral therapies in inflammatory bowel diseases

Inflammatory bowel disease (IBD) is a chronic immune-mediated condition of the gastrointestinal tract that requires chronic treatment and strict surveillance. Development of new monoclonal antibodies targeting one or a few single cytokines, including anti-tumor necrosis factor agents, anti-IL 12/23 inhibitors, and anti-α4β7 integrin inhibitors, have dominated the pharmacological armamentarium in IBD in the last 20 years. Still, many patients experience incomplete or loss of response or develop serious adverse events and drug discontinuation. Janus kinase (JAK) is key to modulating the signal transduction pathway of several proinflammatory cytokines directly involved in gastrointestinal inflammation and, thus, probably IBD pathogenesis. Targeting the JAK-STAT pathway offers excellent potential for the treatment of IBD. The European Medical Agency has approved three JAK inhibitors for treating adults with moderate to severe Ulcerative Colitis when other treatments, including biological agents, have failed or no longer work or if the patient cannot take them. Although there are currently no approved JAK inhibitors for Crohn's disease, upadacitinib and filgotinib have shown increased remission rates in these patients. Other JAK inhibitors, including gut-selective molecules, are currently being studied IBD. This review will discuss the JAK-STAT pathway, its implication in the pathogenesis of IBD, and the most recent evidence from clinical trials regarding the use of JAK inhibitors and their safety in IBD patients.

Herpes zoster in patients with inflammatory arthritides or ulcerative colitis treated with tofacitinib, baricitinib or upadacitinib: a systematic review of clinical trials and real-world studies

JAK inhibitors (JAKi) are new targeted-synthetic drugs, approved for various immune-mediated inflammatory diseases (IMIDs), including inflammatory arthritides (rheumatoid arthritis-RA, psoriatic arthritis-PsA, ankylosing spondylitis-AS) and ulcerative colitis (UC). JAKi have been associated with increased risk for herpes zoster (HZ), but the relative risk among different JAKi in these IMIDs remains unclear. We aimed to systematically review the incidence of HZ among RA, PsA, AS and UC patients treated with the approved doses of tofacitinib (TOFA), baricitinib (BARI) or upadacitinib (UPA). PubMed, Embase, Scopus, Cochrane and Web-of-Science were searched up to 30 March 2022. Clinical trials and real-world studies (RWS) were included. Outcomes assessed were the incidence rate (/100 patient-years) or/and cumulative incidence of HZ. From 1710 records, 53 clinical trials and 25 RWS were included (RA: 54, PsA: 8, AS: 4, and UC: 12). In clinical trials, the HZ-incidence was higher in TOFA-treated patients with RA (2.2-7.1/100 patient-years) or UC (1.3-7.6/100 patient-years) compared to PsA (1.7/100 patient-years), and with higher doses of TOFA in UC (10 mg/twice daily: 3.2-7.6/100 patient-years vs. 5 mg/twice daily: 1.3-2.3/100 patient-years). Evidence for HZ-risk in JAKi-treated patients with AS and in UPA-treated patients was limited. The HZ-incidence between TOFA and BARI groups in 2 RA RWS did not differ significantly. Concomitant glucocorticoid, but not methotrexate, use in RA increased the HZ-risk. This systematic review showed higher HZ-risk in RA or UC than PsA patients treated with TOFA, in those treated with higher TOFA doses or with concomitant glucocorticoids. Preventive measures and monitoring of JAKi-treated patients with IMIDs are essential in daily practice.

Selective JAK1 inhibitors for the treatment of inflammatory bowel disease

Janus kinase (JAK) inhibitors, also known as jakinibs, are third-generation oral small molecules that have expanded the therapeutic options for the management of chronic inflammatory diseases, including inflammatory bowel disease (IBD). Tofacitinib, a pan-JAK inhibitor, has spearheaded the new JAK class for IBD treatment. Unfortunately, serious adverse effects, including cardiovascular complications such as pulmonary embolism and venous thromboembolism or even death from any cause, have been reported for tofacitinib. However, it is anticipated that next-generation selective JAK inhibitors may limit the development of serious adverse events, leading to a safer treatment course with these novel targeted therapies. Nevertheless, although this drug class was recently introduced, following the launch of second-generation biologics in the late 1990s, it is breaking new ground and has been shown to efficiently modulate complex cytokine-driven inflammation in both preclinical models and human studies. Herein, we review the clinical opportunities for targeting JAK1 signaling in the pathophysiology of IBD, the biology and chemistry underpinning these target-selective compounds, and their mechanisms of actions. We also discuss the potential for these inhibitors in efforts to balance their benefits and harms.

GADECCU 2022 Guideline for the treatment of Ulcerative Colitis. Adaptation and updating of the GETECCU 2020 Guideline

INTRODUCTION

Ulcerative colitis (UC) is a chronic inflammatory disease that compromises the colon, affecting the quality of life of individuals of any age. In practice, there is a wide spectrum of clinical situations. The advances made in the physio pathogenesis of UC have allowed the development of new, more effective and safer therapeutic agents.

OBJECTIVES

To update and expand the evaluation of the efficacy and safety of relevant treatments for remission induction and maintenance after a mild, moderate or severe flare of UC.

RECIPIENTS

Gastroenterologists, coloproctologists, general practitioners, family physicians and others health professionals, interested in the treatment of UC.

METHODOLOGY

GADECCU authorities obtained authorization from GETECCU to adapt and update the GETECCU 2020 Guide for the treatment of UC. Prepared with GRADE methodology. A team was formed that included authors, a panel of experts, a nurse and a patient, methodological experts, and external reviewers. GRADE methodology was used with the new information.

RESULTS

A 118-page document was prepared with the 44 GADECCU 2022 recommendations, for different clinical situations and therapeutic options, according to levels of evidence. A section was added with the new molecules that are about to be available.

CONCLUSIONS

This guideline has been made in order to facilitate decision-making regarding the treatment of UC, adapting and updating the guide prepared by GETECCU in the year 2020.

Tyk2 Targeting in Immune-Mediated Inflammatory Diseases

The Janus kinase (Jak)/signal transducer and activating protein (STAT) pathways mediate the intracellular signaling of cytokines in a wide spectrum of cellular processes. They participate in physiologic and inflammatory cascades and have become a major focus of research, yielding novel therapies for immune-mediated inflammatory diseases (IMID). Genetic linkage has related dysfunction of Tyrosine kinase 2 (Tyk2)-the first member of the Jak family that was described-to protection from psoriasis. Furthermore, Tyk2 dysfunction has been related to IMID prevention, without increasing the risk of serious infections; thus, Tyk2 inhibition has been established as a promising therapeutic target, with multiple Tyk2 inhibitors under development. Most of them are orthosteric inhibitors, impeding adenosine triphosphate (ATP) binding to the JH1 catalytic domain-which is highly conserved across tyrosine kinases-and are not completely selective. Deucravacitinib is an allosteric inhibitor that binds to the pseudokinase JH2 (regulatory) domain of Tyk2; this unique mechanism determines greater selectivity and a reduced risk of adverse events. In September 2022, deucravacitinib became the first Tyk2 inhibitor approved for the treatment of moderate-to-severe psoriasis. A bright future can be expected for Tyk2 inhibitors, with newer drugs and more indications to come.

Distinct Mechanisms of Mismatch-Repair Deficiency Delineate Two Modes of Response to Anti-PD-1 Immunotherapy in Endometrial Carcinoma

Mismatch repair-deficient (MMRd) cancers have varied responses to immune-checkpoint blockade (ICB). We conducted a phase II clinical trial of the PD-1 inhibitor pembrolizumab in 24 patients with MMRd endometrial cancer (NCT02899793). Patients with mutational MMRd tumors (6 patients) had higher response rates and longer survival than those with epigenetic MMRd tumors (18 patients). Mutation burden was higher in tumors with mutational MMRd compared with epigenetic MMRd; however, within each category of MMRd, mutation burden was not correlated with ICB response. Pretreatment JAK1 mutations were not associated with primary resistance to pembrolizumab. Longitudinal single-cell RNA-seq of circulating immune cells revealed contrasting modes of antitumor immunity for mutational versus epigenetic MMRd cancers. Whereas effector CD8+ T cells correlated with regression of mutational MMRd tumors, activated CD16+ NK cells were associated with ICB-responsive epigenetic MMRd tumors. These data highlight the interplay between tumor-intrinsic and tumor-extrinsic factors that influence ICB response.

SIGNIFICANCE

The molecular mechanism of MMRd is associated with response to anti-PD-1 immunotherapy in endometrial carcinoma. Tumors with epigenetic MMRd or mutational MMRd are correlated with NK cell or CD8+ T cell-driven immunity, respectively. Classifying tumors by the mechanism of MMRd may inform clinical decision-making regarding cancer immunotherapy. This article is highlighted in the In This Issue feature, p. 247.

JAK-STAT signaling as an ARDS therapeutic target: Status and future trends

Acute respiratory distress syndrome (ARDS) is characterized by noncardiogenic pulmonary edema. It has a high mortality rate and lacks effective pharmacotherapy. With the outbreak of COVID-19 worldwide, the mortality of ARDS has increased correspondingly, which makes it urgent to find effective targets and strategies for the treatment of ARDS. Recent clinical trials of Janus kinase (JAK) inhibitors in treating COVID-19-induced ARDS have shown a positive outcome, which makes the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway a potential therapeutic target for treating ARDS. Here, we review the complex cause of ARDS, the molecular JAK/STAT pathway involved in ARDS pathology, and the progress that has been made in strategies targeting JAK/STAT to treat ARDS. Specifically, JAK/STAT signaling directly participates in the progression of ARDS or colludes with other pathways to aggravate ARDS. We summarize JAK and STAT inhibitors with ARDS treatment benefits, including inhibitors in clinical trials and preclinical studies and natural products, and discuss the side effects of the current JAK inhibitors to reveal future trends in the design of JAK inhibitors, which will help to develop effective treatment strategies for ARDS in the future.

JAK-STAT signaling pathway-related gene single nucleotide polymorphisms and susceptibility to ankylosing spondylitis in eastern Chinese Han population

OBJECTIVE

A case-control study was utilized to investigate the relationship between genetic variation of JAK-STAT signaling pathway-related genes and the susceptibility to ankylosing spondylitis (AS).

METHODS

Fifteen SNPs in the JAK-STAT signaling pathway-related genes from 660 AS patients and 646 healthy controls were genotyped using iMLDR technology (JAK1: rs2230587, rs2230588, rs2780815, rs310241; JAK2: rs2274472, rs2230722, rs2230724, rs10758669; STAT1: rs10199181, rs1547550, rs2066802, rs45463799, rs6718902; STAT3: rs3744483; STAT5A: rs1135669).

RESULTS

Allele analysis revealed that the T allele of STAT1 rs6718902 was a protective agent for male AS patients (OR = 0.765, 95% CI = 0.644-0.909). Inheritance models showed that GG + CG as well as GG genotypes of STAT1 rs1547550 had a significant risk of developing AS in males (OR = 5.374, 95%CI = 2.505-11.526; OR = 5.186, 95%CI = 2.412-11.153). The TT + CT and TT genotypes at STAT1 rs6718902 were observed to be associated with a significantly decreased risk of AS compared to CC genotypes among male patients and male controls (OR = 0.637, 95%CI = 0.485-0.837; OR = 0.597, 95%CI = 0.422-0.845). Furthermore, the genotypes of JAK1 gene rs2230588, rs2780815, and rs310241 were correlated with the severity of clinical conditions in female AS patients, while the JAK2 rs2230724 genotypes may affect disease ability in male AS patients.

CONCLUSION

These findings indicated that JAK-STAT signaling pathway-related gene single nucleotide polymorphisms may be associated with AS susceptibility in eastern Chinese Han population. Key Points • The T allele of rs6718902 on the STAT1 gene may be a protective agent for male AS patients. • STAT1 rs1547550 GG + CG and GG genotypes were observed to be connected with a risk of male AS patients. However, STAT1 rs6718902 TT + CT and TT genotypes reduced the susceptibility risk of male AS patients compared to wild-type CC. • The JAK1 genes rs2230588, rs2780815, and rs310241 may affect disease functional status in female AS patients, while the JAK2 rs2230724 genotype was related to disease activity in male AS patients.

Breaking through the therapeutic ceiling of inflammatory bowel disease: Dual-targeted therapies

Emerging biologics and small-molecule drugs have changed the clinical status quo of inflammatory bowel disease (IBD). However, current treatments remain at a standstill in terms of response and remission in many cases. Accumulating evidence indicates that dual-targeted therapy (DTT) could be promising in overcoming the existing ceiling of IBD treatment. However, data on the efficacy and safety of DTT on Crohn's disease and ulcerative colitis are still limited or insufficient. Moreover, there is a lack of studies delineating the mechanisms of DTT. Given that various targeted drugs have different targets among the extensive redundant inflammatory networks, DTT could result in various outcomes. In this review, we have summarized the current data on the safety, effectiveness, and clinical development status of novel targeted drugs related to refractory IBD, and have explored the mechanism of action of therapy. We have categorized therapeutic agents into "Therapeutic Agents Targeting Cellular Signaling Pathways" and "Therapeutic Agents Targeting Leukocyte Trafficking" based on the different therapeutic targets, and also by classifying therapeutic agents targeting the cellular signaling pathways into "JAK-dependent" and "JAK-independent," and placed the existing drug combinations into 3 categories based on their mechanisms, namely, overlapping, synergistic, and complementary effects. Lastly, we have proposed the possible mechanisms of DTT to conceive a theoretical framework for clinical decision-making and further drug development and research from an IBD standpoint.

Efficacy and Safety of JAK1 Inhibitor Abrocitinib in Atopic Dermatitis

Abrocitinib is a JAK1 selective inhibitor recently approved for the treatment of moderate-to-severe atopic dermatitis in adults. It has demonstrated efficacy and safety in several clinical trials, both in children and adults, in monotherapy, and compared with dupilumab. The expected EASI-75 response rate estimates at week 12 are 62.9% (95% CrI 42.5-79.9%) for abrocitinib 200 mg and 43.0% (95% CrI 24.8-64.0%) for abrocitinib 100 mg. Abrocitinib has shown a faster effect than dupilumab as regards early alleviation of itch. Because of the incomplete target selectivity of JAK inhibitors, when abrocitinib treatment is considered, laboratory screening is necessary, latent tuberculosis must be screened for, active infections are a contraindication, and special caution must be exerted in treating elderly patients and those predisposed to thromboembolic events. Even though recent meta-analyses of clinical trials have not shown that atopic dermatitis, or its treatment with JAK inhibitors or dupilumab, modify the risk of deep venous thrombosis or pulmonary embolism, long-term follow-up studies will better define the safety profile of abrocitinib.

Janus Kinase Inhibitors: A New Tool for the Treatment of Axial Spondyloarthritis

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease involving the spine, peripheral joints, and entheses. This condition causes stiffness, pain, and significant limitation of movement. In recent years, several effective therapies have become available based on the use of biologics that selectively block cytokines involved in the pathogenesis of the disease, such as tumor necrosis factor-α (TNFα), interleukin (IL)-17, and IL-23. However, a significant number of patients show an inadequate response to treatment. Over 10 years ago, small synthetic molecules capable of blocking the activity of Janus kinases (JAK) were introduced in the therapy of rheumatoid arthritis. Subsequently, their indication extended to the treatment of other inflammatory rheumatic diseases. The purpose of this review is to discuss the efficacy and safety of these molecules in axSpA therapy.

Bioactive Compounds from Nyctanthes arbor tristis Linn as Potential Inhibitors of Janus Kinases (JAKs) Involved in Rheumatoid Arthritis

Nyctanthes arbor tristis L (NAT) is one of the herbal plants whose parts are commonly used to treat diverse ailment including RA. Although the etiology of the autoimmune disorder RA is still unclear, actions of cytokines have been greatly associated with the mechanism of RA. Despite the huge development of drugs to combat this disorder, the search for alternative medicine is increasing due to the adverse effects of these synthetic drugs. Here, the ability of 30 selected bioactive compounds from the parts of NAT to bind effectively to target proteins of the Janus kinases as a potent inhibitor was predicted in an in silico manner through molecular docking procedure using Autodock 4.2.6 and their interactions visualized using Discovery Studio, followed by evaluating the physiochemical and ADMET properties of compounds of the lowest binding energy comparable to the reference drug baricitinib. Comparing the predicted target information with the standard drug baricitinib, 7 bioactive compounds may be potential lead drug for the treatment of RA owing to their lowest binding energy ranging from - 7.0 kcal/mol to - 10.49 kcal/mol and their pharmacokinetics properties. This can be used for further in vivo and in vitro studies to establish their potency as JAKs inhibitors to treat RA.

Therapeutic implications of current Janus kinase inhibitors as anti-COVID agents: A review

Severe cases of COVID-19 are characterized by hyperinflammation induced by cytokine storm, ARDS leading to multiorgan failure and death. JAK-STAT signaling has been implicated in immunopathogenesis of COVID-19 infection under different stages such as viral entry, escaping innate immunity, replication, and subsequent inflammatory processes. Prompted by this fact and prior utilization as an immunomodulatory agent for several autoimmune, allergic, and inflammatory conditions, Jakinibs have been recognized as validated small molecules targeting the rapid release of proinflammatory cytokines, primarily IL-6, and GM-CSF. Various clinical trials are under investigation to evaluate Jakinibs as potential candidates for treating COVID-19. Till date, there is only one small molecule Jakinib known as baricitinib has received FDA-approval as a standalone immunomodulatory agent in treating critical COVID-19 patients. Though various meta-analyses have confirmed and validated the safety and efficacy of Jakinibs, further studies are required to understand the elaborated pathogenesis of COVID-19, duration of Jakinib treatment, and assess the combination therapeutic strategies. In this review, we highlighted JAK-STAT signalling in the pathogenesis of COVID-19 and clinically approved Jakinibs. Moreover, this review described substantially the promising use of Jakinibs and discussed their limitations in the context of COVID-19 therapy. Hence, this review article provides a concise, yet significant insight into the therapeutic implications of Jakinibs as potential anti-COVID agents which opens up a new horizon in the treatment of COVID-19, effectively.