Small molecule approaches to treat autoimmune and inflammatory diseases (Part III): Targeting cytokines and cytokine receptor complexes

Mapping conditional health literacy and digital health literacy in patients with inflammatory bowel disease to optimise availability of digital health information: a cross-sectional study

BACKGROUND AND AIMS

Health literacy and digital health literacy are crucial for spreading information that enhances self-management and health outcomes. IBD patients have called for relevant and reliable information to enable self-management. However, mapping conditional capacities for adapting IBD health information remains unaddressed. This study examines IBD patients' health literacy and digital health literacy covariance with clinical, demographic and patient-reported outcomes.

METHODS

This cross-sectional study recruited patients between April 2023 to February 2024 from a Norwegian university hospital. Canonical correlations identified maximum covariance between health literacy and digital health literacy dimensions against clinical, demographic and patient-reported characteristics. Hierarchical clustering of covariance patterns were compared on external variables using bivariate analyses and logistic regression.

RESULTS

Of 432 consents, 380 (87.96%) IBD patients ≥ 18 years were included. Mean age was 43.6 (14.9) years, 173 (45.5%) had UC, 207 (54.5%) had CD, and 108 (53%) were male. Self-efficacy, illness perception, health status and age correlated with several health literacy and digital health literacy dimensions. Of two identified patient clusters, cluster 1 embodied patients with lowest levels of health literacy, digital health literacy, self-efficacy, health status, illness perception and longest disease duration. Cluster 1 demonstrated significantly lower medication adherence and QoL, higher rates of unemployment, elevated disease activity and fewer receiving biological treatment. Disease activity and biological treatment were the strongest predictors of cluster membership.

CONCLUSIONS

The findings emphasize the necessity of addressing clinical characteristics alongside health literacy and digital health literacy in the dissemination of IBD health information.

A hybrid protocol for peptide development: integrating deep generative models and physics simulations for biomolecular design targeting IL23R/IL23

Recent advances in machine learning have revolutionized molecular design; however, a gap remains in integrating generative models with physics-based simulations to develop functional modulators, such as stable peptides, for challenging targets like the interleukin-23 receptor (IL23R) and its associated cytokine, interleukin-23 (IL23). The IL23R/IL23 axis plays a critical role in autoimmune diseases, and current therapies have largely been limited to antibody-based approaches. To address this gap, we employed a hybrid computational approach that combines Long Short-Term Memory (LSTM) networks for peptide generation, a Gated Recurrent Unit (GRU)-based classifier for anti-inflammatory property prediction, and molecular dynamics (MD) simulations to assess structural dynamics, binding interactions, as well as key properties such as binding affinity and stability. Using this hybrid framework, we identified novel inhibitory peptides, particularly P4, with an IC50 of 2 μM. Systematic experimental validation established its inhibitory activity, elucidated its binding mechanism, confirmed its specificity toward the IL23R, and demonstrated its ability to disrupt IL23R/IL23 interaction. This integrated approach highlights the significant potential of combining deep learning and simulations to accelerate the identification of peptide-based therapeutics targeting key protein targets.

At The Interface: Small-Molecule Inhibitors of Soluble Cytokines

Cytokines are crucial regulators of the immune system that orchestrate interactions between cells and, when dysregulated, contribute to the progression of chronic inflammation, cancer, and autoimmunity. Numerous biologic-based clinical agents, mostly monoclonal antibodies, have validated cytokines as important clinical targets and are now part of the standard of care for a number of diseases. These agents, while impactful, still suffer from limitations including a lack of oral bioavailability, high cost of production, and immunogenicity. Small-molecule cytokine inhibitors are attractive alternatives that can address these limitations. Although targeting cytokine-cytokine receptor complexes with small molecules has been a challenging research endeavor, multiple small-molecule inhibitors have now been identified, with a number of them undergoing clinical evaluation. In this review, we highlight the recent advancements in the discovery and development of small-molecule inhibitors targeting soluble cytokines. The strategies for identifying these novel ligands as well as the structural and mechanistic insights into their activity represent important milestones in tackling these challenging and clinically important protein-protein interactions.

Transcriptomic Analysis Reveals the Potential Mechanism of Cardamine circaeoides Hook.f. & Thomson in Lowering Serum Uric Acid by Reducing Inflammatory State Through CCR7 Target

Cardamine circaeoides Hook.f. & Thomson (CC) is a traditional medicinal herb with multiple biological activities. In previous studies, we have identified its serum uric acid (SUA) lowering effects and speculated that Cardamine circaeoides water extract (CCE) may exert anti-hyperuricemia effects related to its anti-inflammatory activity. This study aims to further investigate the molecular mechanism underlying these effects at the mRNA level through transcriptomic analysis, quantitative reverse transcription polymerase chain reaction (RT-qPCR), molecular docking, and Western blotting. CCE effectively reduced SUA and improved renal function in a dose-dependent manner in hyperuricemia rats. Cytokine-cytokine receptor interaction pathway was significantly altered by CCE. An additional study identified a number of genes (IL27, Inhbe, CCR7, CXCR3, IL12RB1, CXCR5, Mstn, and GDF5) as regulators of the inflammatory response. Meanwhile, three key targets (IL27, Inhbe, and CCR7) were found to be significantly expressed at the mRNA level and have strong binding affinity with 22 components, among which Kaempferol 3-sophoroside 7-glucoside, Kaempferol-3-O-sophoroside, and Quercetin 3-sophoroside 7-glucoside have strong binding activities. Following this, Western blotting showed a significant increase in CCR7 expression. Our findings indicated that CCE regulated the cytokine-cytokine receptor interaction pathway through CCR7 to reduce the inflammatory state and exert an SUA-lowering effect.

Targeting cytokine networks in neuroinflammatory diseases

In neuroinflammatory diseases, systemic (blood-borne) leukocytes invade the central nervous system (CNS) and lead to tissue damage. A causal relationship between neuroinflammatory diseases and dysregulated cytokine networks is well established across several preclinical models. Cytokine dysregulation is also observed as an inadvertent effect of cancer immunotherapy, where it often leads to neuroinflammation. Neuroinflammatory diseases can be separated into those in which a pathogen is at the centre of the immune response and those of largely unknown aetiology. Here, we discuss the pathophysiology, cytokine networks and therapeutic landscape of 'sterile' neuroinflammatory diseases such as multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), neurosarcoidosis and immune effector cell-associated neurotoxicity syndrome (ICANS) triggered by cancer immunotherapy. Despite successes in targeting cytokine networks in preclinical models of neuroinflammation, the clinical translation of targeting cytokines and their receptors has shown mixed and often paradoxical responses.

Ironing Out the Mechanism of gp130 Signaling

gp130 functions as a shared signal-transducing subunit not only for interleukin (IL)-6 but also for eight other human cytokine receptor complexes. The IL-6 signaling pathway mediated through gp130 encompasses classical, trans, or cluster signaling, intricately regulated by a diverse array of modulators affecting IL-6, its receptor, and gp130. Currently, only a limited number of small molecule antagonists and agonists for gp130 are known. This review aims to comprehensively examine the current knowledge of these modulators and provide insights into their pharmacological properties, particularly in the context of cancer and other diseases. Notably, the prominent gp130 modulators SC144, bazedoxifene, and raloxifene are discussed in detail, with a specific focus on the discovery of SC144's iron-chelating properties. This adds a new dimension to the understanding of its pharmacological effects and therapeutic potential in conditions where iron homeostasis is significant. Our bioinformatic analysis of gp130 and genes related to iron homeostasis reveals insightful correlations, implicating the role of iron in the gp130 signaling pathway. Overall, this review contributes to the evolving understanding of gp130 modulation and its potential therapeutic applications in various disease contexts. SIGNIFICANCE STATEMENT: This perspective provides a timely and comprehensive analysis of advancements in gp130 signaling research, emphasizing the therapeutic implications of the currently available modulators. Bioinformatic analysis demonstrates potential interplay between gp130 and genes that regulate iron homeostasis, suggesting new therapeutic avenues. By combining original research findings with a broader discussion of gp130's therapeutic potential, this perspective significantly contributes to the field.

Recent insights of PROTAC developments in inflammation-mediated and autoimmune targets: a critical review

According to the mounting evidence in the literature, pro-inflammatory mediators/targets activate multiple signalling pathways to trigger illnesses that are ultimately responsible for acute pain, chronic inflammatory diseases, and several auto-immune disorders. Conventional drugs have been ruled out since proteolysis-targeting chimeras (PROTACs) are poised to overcome the limitations of traditional therapies. These heterobifunctional molecules help to degrade the targeted proteins of interest through ubiquitination. This review encompasses current and future aspects of PROTACs in inflammation-mediated and autoimmune targets. Different key points are highlighted and discussed, such as why PROTACs are preferred in this disease area, drawbacks and lessons learnt from the past, the role of linkers in establishing crucial degradation, in vitro findings, pharmacokinetics, in silico parameters, limitations of PROTACs in clinical settings, and future outcomes.

Safety, Tolerability, and Pharmacokinetics of an Oral Small Molecule Inhibitor of IL-17A (LY3509754): A Phase I Randomized Placebo-Controlled Study

For some patients with psoriasis, orally administered small molecule inhibitors of interleukin (IL)-17A may represent a convenient alternative to IL-17A-targeting monoclonal antibodies. This first-in-human study assessed the safety, tolerability, pharmacokinetics (PKs), and peripherally circulating IL-17A target engagement profile of single or multiple oral doses of the small molecule IL-17A inhibitor LY3509754 (NCT04586920). Healthy participants were randomly assigned to receive LY3509754 or placebo in sequential escalating single ascending dose (SAD; dose range 10-2,000 mg) or multiple ascending dose (MAD; dose range 100-1,000 mg daily for 14 days) cohorts. The study enrolled 91 participants (SAD, N = 51 and MAD, N = 40) aged 21-65 years (71% men). LY3509754 had a time to maximum concentration (Tmax) of 1.5-3.5 hours, terminal half-life of 11.4-19.1 hours, and exhibited dose-dependent increases in exposure. LY3509754 had strong target engagement, indicated by elevated plasma IL-17A levels within 12 hours of dosing. Four participants from the 400-mg (n = 1) and 1,000-mg (n = 3) MAD cohorts experienced increased liver transaminases or acute hepatitis (onset ≥ 12 days post-last LY3509754 dose), consistent with drug-induced liver injury (DILI). One case of acute hepatitis was severe, resulted in temporary hospitalization, and was classified as a serious adverse event. No adverse effects on other major organ systems were observed. Liver biopsies from three of the four participants revealed lymphocyte-rich, moderate-to-severe lobular inflammation. We theorize that the DILI relates to an off-target effect rather than IL-17A inhibition. In conclusion, despite strong target engagement and a PK profile that supported once-daily administration, this study showed that oral dosing with LY3509754 was poorly tolerated.

Prophylactic Mitigation of Acute Graft versus Host Disease by Novel 2-(Pyrrolidin-1-ylmethyl)pyrrole-Based Stimulation-2 (ST2) Inhibitors

Hematopoietic cell transplantation (HCT) is a proven and potentially curable therapy for hematological malignancies and inherited hematological disease. The main risk of HCT is the development of graft versus host disease (GVHD) acquired in up to 50% of patients. Upregulation of soluble ST2 (sST2) is a key clinical biomarker for GVHD prognosis and was shown to be a potential therapeutic target for GVHD. Agents targeting sST2 to reduce the sST2 level after HCT have the potential to mitigate GVHD progression. Here, we report 32 (or XY52) as the lead ST2 inhibitor from our optimization campaign. XY52 had improved inhibitory activity and metabolic stability in vitro and in vivo. XY52 suppressed proinflammatory T-cell proliferation while increasing regulatory T cells in vitro. In a clinically relevant GVHD model, a 21-day prophylactic regimen of XY52 reduced plasma sST2 and IFN-γ levels and GVHD score and extended survival in mice. XY52 represented a significant improvement over our previous compound, iST2-1, and further optimization of XY52 is warranted. The small-molecule ST2 inhibitors can potentially be used as a biomarker-guided therapy for mitigating GVHD in future clinical applications.

Unbiased molecular dynamics simulation of a first-in-class small molecule inhibitor binds to oncostatin M

Small molecule inhibitors (SMIs) targeting oncostatin M (OSM) signaling pathway represent new therapeutics to combat cancer, inflammatory bowel disease (IBD) and CNS disease. Recently, the first-in-class SMI named SMI-10B that target OSM and block its interaction with receptor (OSMR) were reported. However, the binding pocket and interaction mode of the compound on OSM remain poorly understood, which hampering the rational design of SMIs that target OSM. Here, using SMI-10B as a probe, the multiple pockets on OSM for small molecules binding were extensively explored by unbiased molecular dynamics (MD) simulations. Then, the near-native structure of the complex was identified by molecular mechanics generalized Born surface area (MM/GBSA) binding energy funnel. Moreover, the binding stabilities of the protein-ligand complexes in near- and non-native conformations were verified by additional independent MD runs and absolute free energy perturbation (FEP) calculation. In summary, the unique feature of SMI-10B spontaneously binds to OSM characterized here not only provide detailed information for understanding the molecular mechanism of SMI-10B binding to OSM, but also will facilitate the rational design of novel and more potent SMIs to block OSM signaling.

New, Low-Molecular Weight Chemical Compounds Inhibiting Biological Activity of Interleukin 15

Chronic overproduction of IL-15 contributes to the pathogenesis of numerous inflammatory and autoimmune disorders. Experimental methods used to reduce the cytokine activity show promise as potential therapeutic approaches to modify IL-15 signaling and alleviate the development and progression of IL-15-related diseases. We previously demonstrated that an efficient reduction of IL-15 activity can be obtained by selective blocking of the specific, high affinity subunit alpha of the IL-15 receptor (IL-15Rα) with small-molecule inhibitors. In this study, we determined the structure-activity relationship of currently known IL-15Rα inhibitors in order to define the critical structural features required for their activity. To validate our predictions, we designed, analyzed in silico, and assessed in vitro function of 16 new potential IL-15Rα inhibitors. All newly synthesized molecules were benzoic acid derivatives with favorable ADME properties and they efficiently reduced IL-15 dependent peripheral blood mononuclear cells (PBMCs) proliferation, as well as TNF-α and IL-17 secretion. The rational design of IL-15 inhibitors may propel the identification of potential lead molecules for the development of safe and effective therapeutic agents.

Transcriptomic analysis of spleen B cell revealed the molecular basis of bursopentin on B cell differentiation

The bursa of Fabricius, the acknowledged humoral immune organ unique to birds, plays a vital role in B cell development. Bursopentin (BP5) derived from the bursa is reported to induce the development and formation of B cells. However, the mechanism of BP5 on B cell differentiation is still unclear. In this paper, total B lymphocytes from mice immunized with H9N2 subtype AIV vaccine were stimulated with BP5. The results show that BP5 at the experimental dosages promoted B cell differentiation, including the total B cells, activated B cells, differentiated B cells, mature B cells and plasma cells. Then, the in vivo immune experiment proved that the percentages of activated and differentiated B cells from mice immunized with AIV vaccine and 0.25 mg/mL BP5 were increased. To investigate the molecular mechanism of BP5 on B cell differentiation, the gene expression profiles of B cells purified from the spleen cells of mice immunized with AIV vaccine and BP5 were detected following RNA sequencing technology. The results show that BP5 at 0.05 and 0.25 mg/mL induced the enrichment of various biological functions, and stimulated five common significant enrichment pathways in B cells from the immunized mice. Additionally, 120 and 59 differentially expressed genes (DEG) represented transcriptional factors in B cells following 0.05 and 0.25 mg/mL BP5 immunization, respectively. In summary, these results suggest that BP5 regulates various gene expression involved in regulation of B cell development, which provides the knowledge required for additional studies on B cell differentiation in response to bursal-derived peptides and also provides an important experimental basis for improving vaccine immunity.