Harnessing ZIKV NS2A RNA for alleviating acute hepatitis and cytokine release storm by targeting translation machinery.

Background And Aims: Hyperactivated inflammatory responses induced by cytokine release syndrome are the primary causes of tissue damage and even death. The translation process is precisely regulated to control the production of proinflammatory cytokines. However, it is largely unknown whether targeting translation can effectively limit the hyperactivated inflammatory responses during acute hepatitis and graft-versus-host disease.

Inhibition of lysosome-tethered Ragulator-Rag-3D complex restricts the replication of Enterovirus 71 and Coxsackie A16.

Enterovirus 71 (EV71) and Coxsackie A16 (CVA16) are two major causative agents of hand, foot, and mouth disease (HFMD) in young children. However, the mechanisms regulating the replication and pathogenesis of EV71/CVA16 remain incompletely understood. We performed a genome-wide CRISPR-Cas9 knockout screen and identified Ragulator as a mediator of EV71-induced apoptosis and pyroptosis.

Synthesis and evaluation of dihydrofuro[2,3-b]pyridine derivatives as potent IRAK4 inhibitors.

Interleukin-1 receptor-associated kinase 4 (IRAK4) is a key regulator to control downstream NF-κB and MAPK signals in the innate immune response and has been proposed as a therapeutic target for the treatment of inflammatory and autoimmune diseases. Herein, a series of IRAK4 inhibitors based on a dihydrofuro[2,3-b]pyridine scaffold was developed. Structural modifications of the screening hit 16 (IC = 243 nM) led to IRAK4 inhibitors with improved potency but high clearance (Cl) and poor oral bioavailability, as exemplified by compound 21 (IC = 6.

Discovery of a novel RIPK2 inhibitor for the treatment of inflammatory bowel disease.

Nucleotide-binding oligomerization domain-containing protein 1 and 2 (NOD 1/2) are important cytosolic pattern recognition receptors that initiate host immune response. The dysregulation of NOD signaling is highly associated with inflammatory bowel disease (IBD) that needs novel treatment options. Receptor-interacting protein kinase 2 (RIPK2) is a critical mediator of NOD signaling and considered a promising therapeutic target for IBD treatment.

Design, synthesis, evaluation and optimization of potent IRAK4 inhibitors alleviating production of inflammatory cytokines in LPS-induced SIRS model.

Interleukin-1 receptor associated kinase-4 (IRAK4) has emerged as a therapeutic target for inflammatory and autoimmune diseases. Through reversing the amide of CA-4948 and computer aided structure-activity relationship (SAR) studies, a series of IRAK4 inhibitors with oxazolo[4,5-b]pyridine scaffold were identified. Compound 32 showed improved potency (IC = 43 nM) compared to CA-4948 (IC = 115 nM), but suffered from hERG inhibition (IC = 5.

Apoptotic cell death in disease-Current understanding of the NCCD 2023.

Apoptosis is a form of regulated cell death (RCD) that involves proteases of the caspase family. Pharmacological and genetic strategies that experimentally inhibit or delay apoptosis in mammalian systems have elucidated the key contribution of this process not only to (post-)embryonic development and adult tissue homeostasis, but also to the etiology of multiple human disorders. Consistent with this notion, while defects in the molecular machinery for apoptotic cell death impair organismal development and promote oncogenesis, the unwarranted activation of apoptosis promotes cell loss and tissue damage in the context of various neurological, cardiovascular, renal, hepatic, infectious, neoplastic and inflammatory conditions.

A novel RIPK1 inhibitor reduces GVHD in mice via a nonimmunosuppressive mechanism that restores intestinal homeostasis.

Intestinal epithelial cells (IECs) are implicated in the propagation of T-cell-mediated inflammatory diseases, including graft-versus-host disease (GVHD), but the underlying mechanism remains poorly defined. Here, we report that IECs require receptor-interacting protein kinase-3 (RIPK3) to drive both gastrointestinal (GI) tract and systemic GVHD after allogeneic hematopoietic stem cell transplantation. Selectively inhibiting RIPK3 in IECs markedly reduces GVHD in murine intestine and liver.

Discovery, optimization and evaluation of isothiazolo[5,4-b]pyridine derivatives as RIPK1 inhibitors with potent in vivo anti-SIRS activity.

Receptor-interacting protein kinase-1 (RIPK1) is involved in the necroptosis pathway, which regulates inflammatory signaling and cell death in a variety of diseases, including inflammatory and neurodegenerative disorders. We identified a novel hit compound 36 by a cell-based screening assay (anti-necroptosis EC = 58 nM). Starting from compound 36, we designed a series of scaffolds to improve anti-necroptosis activity, physicochemical properties and metabolic stability.

Temporal Proteomic and Phosphoproteomic Analysis of EV-A71-Infected Human Cells.

Human enterovirus A71 (EV-A71), a member of the Picornaviridae family, is one of the main etiological viruses that lead to hand, foot, and mouth disease (HFMD). We utilized a multiplex tandem mass tag-based quantitative proteomic technique to monitor the alternation of the whole cell proteome and phosphoproteome of human rhabdomyosarcoma cells over the course of EV-A71 infection. We successfully quantified more than 7000 host proteins and 17,000 phosphosites, of which 80 proteins and nearly 1700 phosphosites were significantly regulated upon viral infection.

Design, synthesis, and structure-activity relationship of novel RIPK2 inhibitors.

The NOD1/2 (nucleotide-binding oligomerization domain-containing protein 1/2) signaling pathways are involved in innate immune control and host defense. NOD dysfunction can result in a variety of autoimmune disorders. NOD-induced generation of inflammatory cytokines is mediated by receptor-interacting protein kinase 2 (RIPK2), which has been considered as a promising therapeutic target.

XAF1 Protects Host against Emerging RNA Viruses by Stabilizing IRF1-Dependent Antiviral Immunity.

XIAP-associated factor 1 (XAF1) is an interferon (IFN)-stimulated gene (ISG) that enhances IFN-induced apoptosis. However, it is unexplored whether XAF1 is essential for the host fighting against invaded viruses. Here, we find that XAF1 is significantly upregulated in the host cells infected with emerging RNA viruses, including influenza, Zika virus (ZIKV), and SARS-CoV-2.

Interferon-mediated repression of miR-324-5p potentiates necroptosis to facilitate antiviral defense.

Mixed lineage kinase domain-like protein (MLKL) is the terminal effector of necroptosis, a form of regulated necrosis. Optimal activation of necroptosis, which eliminates infected cells, is critical for antiviral host defense. MicroRNAs (miRNAs) regulate the expression of genes involved in various biological and pathological processes.

Synthesis and characterization of potent RIPK3 inhibitors based on a tricyclic scaffold.

Necroptosis is an important form of regulated cell death involved in inflammatory diseases, degenerative diseases and cancer. RIPK3 is an interesting target for intervention of necroptosis-associated diseases. Herein the authors report the synthesis of a series RIPK3 inhibitors under the guidance of structure-based drug design which leads to the identification of compound .

Design, synthesis, and evaluation of potent RIPK1 inhibitors with in vivo anti-inflammatory activity.

RIPK1 plays a key role in the necroptosis pathway that regulates inflammatory signaling and cell death in various diseases, including inflammatory and neurodegenerative diseases. Herein, we report a series of potent RIPK1 inhibitors, represented by compound 70. Compound 70 efficiently blocks necroptosis induced by TNFα in both human and mouse cells (EC = 17-30 nM).

STING-mediated degradation of IFI16 negatively regulates apoptosis by inhibiting p53 phosphorylation at serine 392.

Interferon-γ-inducible factor 16 (IFI16) triggers stimulator of interferon (IFN) genes (STING)-dependent type I IFN production during host antiviral immunity and facilitates p53-dependent apoptosis during suppressing tumorigenesis. We have previously reported that STING-mediated IFI16 degradation negatively regulates type I IFN production. However, it is unknown whether STING also suppresses IFI16/p53-dependent apoptosis via degradation of IFI16.

Ring closure strategy leads to potent RIPK3 inhibitors.

Necroptosis is a form of regulated necrotic cell death that is independent of caspases. Receptor-interacting protein kinase 3 (RIPK3) has been identified as a key regulator for necroptosis, and has been proposed as a potential therapeutic target for the treatment of diseases associated with necroptosis. In this report, we describe the design, synthesis, and evaluation of a series of novel RIPK3 inhibitors.

Discovery of a Potent RIPK3 Inhibitor for the Amelioration of Necroptosis-Associated Inflammatory Injury.

Necroptosis is a form of regulated necrosis that requires the activation of receptor-interacting kinase 3 (RIPK3 or RIP3) and its phosphorylation of the substrate MLKL (mixed lineage kinase domain-like protein). Necroptosis has emerged as important cell death involved in the pathogenesis of various diseases including inflammatory diseases, degenerative diseases, and cancer. Here, we discovered a small molecule Zharp-99 as a potent inhibitor of necroptosis through blocking the kinase activity of RIPK3.

Design, synthesis, and evaluation of pyrrolidine based CXCR4 antagonists with in vivo anti-tumor metastatic activity.

The chemokine receptor CXCR4 has been proposed as a drug target based on its important functions in HIV infection, inflammation/autoimmune diseases and cancer metastasis. Herein we report the design, synthesis and evaluation of novel CXCR4 antagonists based on a pyrrolidine scaffold. The structural exploration/optimization identified numerous potent CXCR4 antagonists, represented by compound 46, which displayed potent binding affinity to CXCR4 receptor (IC = 79 nM competitively displacing fluorescent 12G5 antibody) and inhibited CXCL12 induced cytosolic calcium flux (IC = 0.

Correction: The Natural Pesticide Dihydrorotenone Induces Human Plasma Cell Apoptosis by Triggering Endoplasmic Reticulum Stress and Activating p38 Signaling Pathway.

[This corrects the article DOI: 10.1371/journal.pone.

Doxorubicin sensitizes cancer cells to Smac mimetic via synergistic activation of the CYLD/RIPK1/FADD/caspase-8-dependent apoptosis.

Smac/Diablo is a pro-apoptotic protein via interaction with inhibitors of apoptosis proteins (IAPs) to relieve their inhibition of caspases. Smac mimetic compounds (also known as antagonists of IAPs) mimic the function of Smac/Diablo and sensitize cancer cells to TNF-induced apoptosis. However, the majority of cancer cells are resistant to Smac mimetic alone.

MicroRNA-381-3p Functions as a Dual Suppressor of Apoptosis and Necroptosis and Promotes Proliferation of Renal Cancer Cells.

Renal cell carcinoma (RCC) is the most common type of kidney cancer. It has a poor prognosis, with approximately 20-30% of patients developing recurrent and/or metastatic diseases that is relatively high resistant to conventional therapy. Resisting cell death is a hallmark of cancer cells.

Design, Synthesis, and Characterization of Novel CXCR4 Antagonists Featuring Cyclic Amines.

Chemokine receptor CXCR4 and its natural ligand CXCL12 (also known as stromal cell-derived factor-1, or SDF-1) regulate a broad range of physiological functions. Dysregulation of the CXCL12/CXCR4 axis is involved in numerous pathological conditions such as HIV infection, inflammation and cancer. Herein, we report the design, synthesis, and characterization of novel CXCR4 antagonists based on cyclic amine scaffolds.

Design, synthesis, and evaluation of novel CXCR4 antagonists based on an aminoquinoline template.

The chemokine receptor CXCR4 has been explored as a drug target due to its involvement in pathological conditions such as HIV infection and cancer metastasis. Here we report the structure-activity relationship study of novel CXCR4 antagonists based on an aminoquinoline template. This template is devoid of the chiral center in the classical tetrahydroquinoline (THQ) ring moiety and therefore can be easily synthesized.

Manipulation of Host Cell Death Pathways by Herpes Simplex Virus.

Herpes simplex virus (HSV)-1 and HSV-2 are ubiquitous human pathogens that infect keratinized epithelial surfaces and establish lifelong latent infection in sensory neurons of the peripheral nervous system. HSV-1 causes oral cold sores, and HSV-2 causes genital lesions characterized by recurrence at the site of the initial infection. In multicellular organisms, cell death plays a pivotal role in host defense by eliminating pathogen-infected cells.