RESUMEN
The ongoing evolution of SARS-CoV-2 to evade vaccines and therapeutics underlines the need for innovative therapies with high genetic barriers to resistance. Therefore, there is pronounced interest in identifying new pharmacological targets in the SARS-CoV-2 viral life cycle. The small molecule PAV-104, identified through a cell-free protein synthesis and assembly screen, was recently shown to target host protein assembly machinery in a manner specific to viral assembly. In this study, we investigate the capacity of PAV-104 to inhibit SARS-CoV-2 replication in human airway epithelial cells (AECs). We show that PAV-104 inhibits >99% of infection with diverse SARS-CoV-2 variants in immortalized AECs, and in primary human AECs cultured at the air-liquid interface (ALI) to represent the lung microenvironment in vivo. Our data demonstrate that PAV-104 inhibits SARS-CoV-2 production without affecting viral entry, mRNA transcription, or protein synthesis. PAV-104 interacts with SARS-CoV-2 nucleocapsid (N) and interferes with its oligomerization, blocking particle assembly. Transcriptomic analysis reveals that PAV-104 reverses SARS-CoV-2 induction of the type-I interferon response and the maturation of nucleoprotein signaling pathway known to support coronavirus replication. Our findings suggest that PAV-104 is a promising therapeutic candidate for COVID-19 with a mechanism of action that is distinct from existing clinical management approaches.
Asunto(s)
Antivirales , Células Epiteliales , SARS-CoV-2 , Replicación Viral , Humanos , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/fisiología , Replicación Viral/efectos de los fármacos , Células Epiteliales/virología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Antivirales/farmacología , Ensamble de Virus/efectos de los fármacos , COVID-19/virología , Tratamiento Farmacológico de COVID-19RESUMEN
The ongoing evolution of SARS-CoV-2 to evade vaccines and therapeutics underlines the need for novel therapies with high genetic barriers to resistance. The small molecule PAV-104, identified through a cell-free protein synthesis and assembly screen, was recently shown to target host protein assembly machinery in a manner specific to viral assembly. Here, we investigated the capacity of PAV-104 to inhibit SARS-CoV-2 replication in human airway epithelial cells (AECs). Our data demonstrate that PAV-104 inhibited > 99% of infection with diverse SARS-CoV-2 variants in primary and immortalized human AECs. PAV-104 suppressed SARS-CoV-2 production without affecting viral entry or protein synthesis. PAV-104 interacted with SARS-CoV-2 nucleocapsid (N) and interfered with its oligomerization, blocking particle assembly. Transcriptomic analysis revealed that PAV-104 reversed SARS-CoV-2 induction of the Type-I interferon response and the 'maturation of nucleoprotein' signaling pathway known to support coronavirus replication. Our findings suggest that PAV-104 is a promising therapeutic candidate for COVID-19.
RESUMEN
This letter describes the structure-activity relationship (SAR) of the 'right-wing' α-amino acid residue of potent tetrahydroisoquinoline (THIQ)-derived LFA-1/ICAM-1 antagonists. Novel (S)-substituted heteroaryl-bearing α-amino acids have been identified as replacements of the 'right-wing' (S)-2,3-diaminopropanoic acid (DAP) moiety. Improvement of potency in the Hut-78 assay in the presence of 10% human serum has also been achieved.
Asunto(s)
Aminoácidos/química , Molécula 1 de Adhesión Intercelular/química , Antígeno-1 Asociado a Función de Linfocito/química , Tetrahidroisoquinolinas/química , Animales , Molécula 1 de Adhesión Intercelular/metabolismo , Antígeno-1 Asociado a Función de Linfocito/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , Tetrahidroisoquinolinas/síntesis química , Tetrahidroisoquinolinas/farmacocinética , beta-Alanina/análogos & derivados , beta-Alanina/químicaRESUMEN
This letter describes the discovery of a novel series of tetrahydroisoquinoline (THIQ)-derived small molecules that potently inhibit both human T-cell migration and super-antigen induced T-cell activation through disruption of the binding of integrin LFA-1 to its receptor, ICAM-1. In addition to excellent in vitro potency, 6q shows good pharmacokinetic properties and its ethyl ester (6t) demonstrates good oral bioavailability in both mouse and rat. Either intravenous administration of 6q or oral administration of its ethyl ester (6t) produced a significant reduction of neutrophil migration in a thioglycollate-induced murine peritonitis model.
Asunto(s)
Molécula 1 de Adhesión Intercelular/efectos de los fármacos , Antígeno-1 Asociado a Función de Linfocito/efectos de los fármacos , Tetrahidroisoquinolinas/farmacología , Animales , Disponibilidad Biológica , Descubrimiento de Drogas , Humanos , Tetrahidroisoquinolinas/administración & dosificación , Tetrahidroisoquinolinas/farmacocinéticaRESUMEN
Polo-like kinase 1 (Plk1) is a member of the Polo-like kinase family of serine/threonine kinases involved in the regulation of cell-cycle progression and cytokinesis and is an attractive target for the development of anticancer therapeutics. The catalytic domain of this enzyme shares significant primary amino-acid homology and structural similarity with another mitotic kinase, Aurora A. While screening an Aurora A library of ATP-competitive compounds, a urea-containing inhibitor with low affinity for mouse Aurora A but with submicromolar potency for human and zebrafish Plk1 (hPlk1 and zPlk1, respectively) was identified. A crystal structure of the zebrafish Plk1 kinase domain-inhibitor complex reveals that the small molecule occupies the purine pocket and extends past the catalytic lysine into the adaptive region of the active site. Analysis of the structures of this protein-inhibitor complex and of similar small molecules cocrystallized with other kinases facilitates understanding of the specificity of the inhibitor for Plk1 and documents for the first time that Plk1 can accommodate extended ATP-competitive compounds that project toward the adaptive pocket and help the enzyme order its activation segment.
Asunto(s)
Proteínas de Ciclo Celular/química , Proteínas Serina-Treonina Quinasas/química , Proteínas Proto-Oncogénicas/química , Proteínas de Pez Cebra/química , Pez Cebra/metabolismo , Animales , Secuencia de Bases , Dominio Catalítico , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/genética , Cristalografía por Rayos X , Cartilla de ADN , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Conformación Proteica , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , Especificidad por Sustrato , Proteínas de Pez Cebra/antagonistas & inhibidores , Proteínas de Pez Cebra/genética , Quinasa Tipo Polo 1RESUMEN
We report the discovery of a new potent allosteric effector of sickle cell hemoglobin, GBT440 (36), that increases the affinity of hemoglobin for oxygen and consequently inhibits its polymerization when subjected to hypoxic conditions. Unlike earlier allosteric activators that bind covalently to hemoglobin in a 2:1 stoichiometry, 36 binds with a 1:1 stoichiometry. Compound 36 is orally bioavailable and partitions highly and favorably into the red blood cell with a RBC/plasma ratio of â¼150. This partitioning onto the target protein is anticipated to allow therapeutic concentrations to be achieved in the red blood cell at low plasma concentrations. GBT440 (36) is in Phase 3 clinical trials for the treatment of sickle cell disease (NCT03036813).