LY3041658/ interleukin-8 complex structure as targets for IL-8 small molecule inhibitors discovery using a combination of in silico methods

Investigating interleukin-8 in Alzheimer's disease: A comprehensive review

Several studies indicate that the development of Alzheimer's disease (AD) has strong interactions with immune mechanisms within the brain, indicating a close association between inflammation in the central nervous system and the progression of neurodegeneration. Despite considerable progress in understanding the inflammatory aspects of AD, several of them remain unresolved. Pro-inflammatory cytokines and microglia are pivotal components in the inflammatory cascade. Among these, the role of interleukin-8 (IL-8) in neurodegeneration seems complex and multifaceted, involving inflammation, neurotoxicity, blood-brain barrier disruption, and oxidative stress, and is still poorly characterized. We conducted a review to describe the evidence of IL-8 involvement in AD. IL-8 is a cytokine known for its proinflammatory properties and typically produced by macrophages, predominantly functions as a chemotactic signal for attracting neutrophils to inflamed sites in the bloodstream. Interestingly, IL-8 is also present in the brain, where it is primarily released by microglia in response to inflammatory signals. This review aims to provide a comprehensive overview of the structure, function, and regulatory mechanisms of IL-8 relevant to AD pathology.

Structure, function and drug discovery of GPCR signaling

G protein-coupled receptors (GPCRs) are versatile and vital proteins involved in a wide array of physiological processes and responses, such as sensory perception (e.g., vision, taste, and smell), immune response, hormone regulation, and neurotransmission. Their diverse and essential roles in the body make them a significant focus for pharmaceutical research and drug development. Currently, approximately 35% of marketed drugs directly target GPCRs, underscoring their prominence as therapeutic targets. Recent advances in structural biology have substantially deepened our understanding of GPCR activation mechanisms and interactions with G-protein and arrestin signaling pathways. This review offers an in-depth exploration of both traditional and recent methods in GPCR structure analysis. It presents structure-based insights into ligand recognition and receptor activation mechanisms and delves deeper into the mechanisms of canonical and noncanonical signaling pathways downstream of GPCRs. Furthermore, it highlights recent advancements in GPCR-related drug discovery and development. Particular emphasis is placed on GPCR selective drugs, allosteric and biased signaling, polyphamarcology, and antibody drugs. Our goal is to provide researchers with a thorough and updated understanding of GPCR structure determination, signaling pathway investigation, and drug development. This foundation aims to propel forward-thinking therapeutic approaches that target GPCRs, drawing upon the latest insights into GPCR ligand selectivity, activation, and biased signaling mechanisms.

Targeting Olokizumab-Interleukin 6 interaction interface to discover novel IL-6 inhibitors

The IL-6/IL-6R or IL-6/GP130 protein-protein interactions play a significant role in controlling the development of chronic inflammatory diseases, such as rheumatoid arthritis, Castleman disease, psoriasis, and, most recently, COVID-19. Modulating or antagonizing protein-protein interactions of IL6 binding to its receptors by oral drugs promises similar efficacy to biological therapy in patients, namely monoclonal antibodies. In this study, we used a crystal structure of the Fab part of olokizumab in a complex with IL-6 (PDB ID: 4CNI) to uncover starting points for small molecule IL-6 antagonist discovery. Firstly, a structure‑based pharmacophore model of the protein active site cavity was generated to identify possible candidates, followed by virtual screening with a significant database Drugbank. After the docking protocol validation, a virtual screening by molecular docking was carried out and a total of 11 top hits were reported. Detailed analysis of the best scoring molecules was performed with ADME/T analysis and molecular dynamics simulation. Furthermore, the Molecular Mechanics-Generalized Born Surface Area (MM/GBSA) technique has been utilized to evaluate the free binding energy. Based on the finding, one newly obtained compound in this study, namely DB15187, may serve as a lead compound for the discovery of IL-6 inhibitors.Communicated by Ramaswamy H. Sarma.