RESUMEN
Benzoxazoles are important structural motifs in pharmaceutical drugs. Here, we present the heterologous production of 3-hydroxyanthranilate-derived benzoxazoles in the host bacterium Myxococcus xanthus following the expression of two genes from the nataxazole biosynthetic gene cluster of Streptomyces sp. Tü 6176. The M.â xanthus expression strain achieved a benzoxazole titer of 114.6±7.4â mg L-1 upon precursor supplementation, which is superior to other bacterial production systems. Crosstalk between the heterologously expressed benzoxazole pathway and the endogenous myxochelin pathway led to the combinatorial biosynthesis of benzoxazoles featuring a 2,3-dihydroxybenzoic acid (2,3-DHBA) building block. Subsequent inâ vitro studies confirmed that this crosstalk is not only due to the availability of 2,3-DHBA in M.â xanthus, rather, it is promoted by the adenylating enzyme MxcE from the myxochelin pathway, which contributes to the activation of aryl carboxylic acids and delivers them to benzoxazole biosynthesis.
Asunto(s)
Myxococcus xanthus , Streptomyces , Myxococcus xanthus/genética , Myxococcus xanthus/metabolismo , Streptomyces/metabolismo , Benzoxazoles/química , Benzoxazoles/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismoRESUMEN
For the characterization of BOA-OH insensitive plants, we studied the time-dependent effects of the benzoxazolinone-4/5/6/7-OH isomers on maize roots. Exposure of Zea mays seedlings to 0.5 mM BOA-OH elicits root zone-specific reactions by the formation of dark rings and spots in the zone of lateral roots, high catalase activity on root hairs, and no visible defense reaction at the root tip. We studied BOA-6-OH- short-term effects on membrane lipids and fatty acids in maize root tips in comparison to the benzoxazinone-free species Abutilon theophrasti Medik. Decreased contents of phosphatidylinositol in A. theophrasti and phosphatidylcholine in maize were found after 10-30 min. In the youngest tissue, α-linoleic acid (18:2), decreased considerably in both species and recovered within one hr. Disturbances in membrane phospholipid contents were balanced in both species within 30-60 min. Triacylglycerols (TAGs) were also affected, but levels of maize diacylglycerols (DAGs) were almost unchanged, suggesting a release of fatty acids for membrane lipid regeneration from TAGs while resulting DAGs are buildings blocks for phospholipid reconstitution, concomitant with BOA-6-OH glucosylation. Expression of superoxide dismutase (SOD2) and of ER-bound oleoyl desaturase (FAD2-2) genes were contemporaneously up regulated in contrast to the catalase CAT1, while CAT3 was arguably involved at a later stage of the detoxification process. Immuno-responses were not elicited in short-terms, since the expression of NPR1, POX12 were barely affected, PR4 after 6 h with BOA-4/7-OH and PR1 after 24 h with BOA-5/6-OH. The rapid membrane recovery, reactive oxygen species, and allelochemical detoxification may be characteristic for BOA-OH insensitive plants.
Asunto(s)
Meristema , Raíces de Plantas , Benzoxazoles/química , Benzoxazoles/metabolismo , Benzoxazoles/farmacología , Expresión Génica , Lípidos de la Membrana/metabolismo , Lípidos de la Membrana/farmacología , Meristema/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Zea mays/genética , Zea mays/metabolismoRESUMEN
Recent advances in DNA nanotechnology led the fabrication and utilization of various DNA assemblies, but the development of a method to control their global shapes and mechanical flexibilities with high efficiency and repeatability is one of the remaining challenges for the realization of the molecular machines with on-demand functionalities. DNA-binding molecules with intercalation and groove binding modes are known to induce the perturbation on the geometrical and mechanical characteristics of DNA at the strand level, which might be effective in structured DNA assemblies as well. Here, we demonstrate that the chemo-mechanical response of DNA strands with binding ligands can change the global shape and stiffness of DNA origami nanostructures, thereby enabling the systematic modulation of them by selecting a proper ligand and its concentration. Multiple DNA-binding drugs and fluorophores were applied to straight and curved DNA origami bundles, which demonstrated a fast, recoverable, and controllable alteration of the bending persistence length and the radius of curvature of DNA nanostructures. This chemo-mechanical modulation of DNA nanostructures would provide a powerful tool for reconfigurable and dynamic actuation of DNA machineries.
Asunto(s)
Benzoxazoles/química , ADN/química , Doxorrubicina/química , Etidio/química , Sustancias Intercalantes/química , Nanoestructuras/química , Compuestos de Quinolinio/química , Benzoxazoles/metabolismo , ADN/genética , ADN/metabolismo , Doxorrubicina/metabolismo , Etidio/metabolismo , Análisis de Elementos Finitos , Sustancias Intercalantes/metabolismo , Ligandos , Microscopía de Fuerza Atómica , Nanotecnología/métodos , Compuestos de Quinolinio/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , EspectrofotometríaRESUMEN
Benzoxazoles are frequently found in synthetic pharmaceuticals and medicinally active natural products. To facilitate benzoxazole-based drug development, an eco-friendly and rapid platform for benzoxazole production is required. In this study, we have completed the biosynthesis of benzoxazoles in E. coli by coexpressing the minimal set of enzymes required for their biosynthesis. Moreover, by coupling this E. coli-based platform with precursor-directed biosynthesis, we have shown that the benzoxazole biosynthetic system is highly promiscuous in incorporating fluorine, chlorine, nitrile, picolinic, and alkyne functionalities into the scaffold. Our E. coli-based system thus paves the way for straightforward generation of novel benzoxazole analogues through future protein engineering and combinatorial biosynthesis.
Asunto(s)
Benzoxazoles/metabolismo , Vías Biosintéticas/genética , Escherichia coli/metabolismo , Benzoxazoles/análisis , Benzoxazoles/química , Productos Biológicos/química , Productos Biológicos/metabolismo , Cromatografía Líquida de Alta Presión , Escherichia coli/química , Escherichia coli/genética , Ingeniería Metabólica/métodos , Familia de Multigenes , Plásmidos/genética , Plásmidos/metabolismoRESUMEN
Diabetic nephropathy (DN) is resulted from activations of polyol pathway and oxidative stress by abnormal metabolism of glucose, and no specific medication is available. We designed a novel class of benzoxazolone derivatives, and a number of individuals were found to have significant antioxidant activity and inhibition of aldose reductase of the key enzyme in the polyol pathway. The outstanding compound (E)-2-(7-(4-hydroxy-3-methoxystyryl)-2-oxobenzo[d]oxazol-3(2H)-yl)acetic acid was identified to reduce urinary proteins in diabetic mice suggesting an alleviation in the diabetic nephropathy, and this was confirmed by kidney hematoxylin-eosin staining. Further investigations showed blood glucose normalization, declined in the polyol pathway and lipid peroxides, and raised glutathione and superoxide dismutase activity. Thus, we suggest a therapeutic function of the compound for DN which could be attributed to the combination of hypoglycemic, aldose reductase inhibition and antioxidant.
Asunto(s)
Antioxidantes/uso terapéutico , Benzoxazoles/uso terapéutico , Nefropatías Diabéticas/tratamiento farmacológico , Inhibidores Enzimáticos/uso terapéutico , Hipoglucemiantes/uso terapéutico , Aldehído Reductasa/antagonistas & inhibidores , Aldehído Reductasa/metabolismo , Animales , Antioxidantes/síntesis química , Antioxidantes/metabolismo , Benzoxazoles/síntesis química , Benzoxazoles/metabolismo , Diabetes Mellitus Experimental/tratamiento farmacológico , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/metabolismo , Células HEK293 , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/metabolismo , Ratones , Simulación del Acoplamiento Molecular , Estructura Molecular , Unión Proteica , Relación Estructura-ActividadRESUMEN
Despite extensive research on small molecule thrombin inhibitors for oral application in the past decades, only a single double prodrug with very modest oral bioavailability has reached human therapy as a marketed drug. We have undertaken major efforts to identify neutral, non-prodrug inhibitors. Using a holistic analysis of all available internal data, we were able to build computational models and apply these for the selection of a lead series with the highest possibility of achieving oral bioavailability. In our design, we relied on protein structure knowledge to address potency and identified a small window of favorable physicochemical properties to balance absorption and metabolic stability. Protein structure information on the pregnane X receptor helped in overcoming a persistent cytochrome P450 3A4 induction problem. The selected compound series was optimized to a highly potent, neutral, non-prodrug thrombin inhibitor by designing, synthesizing, and testing derivatives. The resulting optimized compound, BAY1217224, has reached first clinical trials, which have confirmed the desired pharmacokinetic properties.
Asunto(s)
Anticoagulantes/síntesis química , Diseño de Fármacos , Trombina/antagonistas & inhibidores , Administración Oral , Animales , Anticoagulantes/química , Anticoagulantes/farmacocinética , Anticoagulantes/farmacología , Benzoxazoles/química , Benzoxazoles/metabolismo , Benzoxazoles/farmacología , Sitios de Unión , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Semivida , Humanos , Imidazoles/química , Imidazoles/metabolismo , Imidazoles/farmacología , Concentración 50 Inhibidora , Masculino , Simulación del Acoplamiento Molecular , Oxazolidinonas/química , Oxazolidinonas/metabolismo , Oxazolidinonas/farmacología , Receptor X de Pregnano/genética , Receptor X de Pregnano/metabolismo , Ratas , Ratas Wistar , Relación Estructura-Actividad , Trombina/metabolismo , Activación Transcripcional/efectos de los fármacosRESUMEN
Acute lung injury (ALI) is a pulmonary disease that acts as a severe acute inflammatory response with no specific drugs. iNOS, a catalyst of the excessive production of NO, has been demonstrated to participate in the inflammatory process, and targeting iNOS may be a promising therapeutic pathway to alleviate ALI. In our research, eighteen new disubstituted benzoxazolone derivatives were synthesized, characterized, and evaluated for activity against NO production in an LPS-induced RAW264.7 cell. The results showed that these compounds could obviously inhibit the over-generation of NO and disubstitution at the 4, N-position of the benzoxazolone ring, presenting better potency than substitution only at the 4-position. Among the analogues generated, compounds 2c, 2d, and 3d showed NO inhibitory activity with IC50 values of 16.43, 14.72, and 13.44 µM and iNOS inhibitory activity with IC50 values of 4.605, 3.342, and 9.733 µM, respectively. Meanwhile, compounds 2c, 2d, and 3d could also inhibit the release of IL-6, IL-1ß in vitro and suppress xylene-induced ear edema in vivo to realize anti-inflammatory activity. Furthermore, compound 2d could significantly protect the LPS-induced ALI, presenting as decreased inflammatory cytokines and obvious pathological changes. Immunohistochemistry and molecular modeling demonstrated that compound 2d significantly inhibited the expression of iNOS in vivo and interacted with iNOS through two hydrogen bindings with the MET368 and ILE195 residues of the iNOS protein. These results demonstrated that compound 2d could be a promising lead structure for iNOS inhibitors, with anti-inflammatory activity to treat LPS-induced acute lung injury.
Asunto(s)
Antiinflamatorios/síntesis química , Benzoxazoles/química , Diseño de Fármacos , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/etiología , Animales , Antiinflamatorios/metabolismo , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Benzoxazoles/metabolismo , Benzoxazoles/farmacología , Benzoxazoles/uso terapéutico , Modelos Animales de Enfermedad , Edema/inducido químicamente , Edema/tratamiento farmacológico , Regulación de la Expresión Génica/efectos de los fármacos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , Pulmón/metabolismo , Pulmón/patología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Peroxidasa/metabolismo , Células RAW 264.7RESUMEN
Transthyretin (TTR) is a homotetrameric protein involved in human amyloidosis, including familial amyloid polyneuropathy (FAP). Discovering small-molecule stabilizers of the TTR tetramer is a therapeutic strategy for these diseases. Tafamidis, the only approved drug for FAP treatment, is not effective for all patients. Herein, we discovered that benzbromarone (BBM), a uricosuric drug, is an effective TTR stabilizer and inhibitor against TTR amyloid fibril formation. BBM rendered TTR more resistant to urea denaturation, similarly to iododiflunisal (IDIF), a very potent TTR stabilizer. BBM competes with thyroxine for binding in the TTR central channel, with an IC50 similar to IDIF and tafamidis. Results obtained by isothermal titration calorimetry (ITC) demonstrated that BBM binds TTR with an affinity similar to IDIF, tolcapone and tafamidis, confirming BBM as a potent binder of TTR. The crystal structure of the BBM-TTR complex shows two molecules binding deeply in the thyroxine binding channel, forming strong intermonomer hydrogen bonds and increasing the stability of the TTR tetramer. Finally, kinetic analysis of the ability of BBM to inhibit TTR fibrillogenesis at acidic pH and comparison with other stabilizers revealed that benzbromarone is a potent inhibitor of TTR amyloidogenesis, adding a new interesting scaffold for drug design of TTR stabilizers.
Asunto(s)
Benzbromarona/química , Reposicionamiento de Medicamentos , Fármacos Neuroprotectores/química , Prealbúmina/química , Tiroxina/química , Amiloide/antagonistas & inhibidores , Benzbromarona/metabolismo , Benzoxazoles/química , Benzoxazoles/metabolismo , Sitios de Unión , Unión Competitiva , Cristalografía por Rayos X , Diflunisal/análogos & derivados , Diflunisal/química , Diflunisal/metabolismo , Expresión Génica , Humanos , Enlace de Hidrógeno , Cinética , Simulación del Acoplamiento Molecular , Fármacos Neuroprotectores/metabolismo , Prealbúmina/agonistas , Prealbúmina/genética , Prealbúmina/metabolismo , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Estabilidad Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Termodinámica , Tiroxina/metabolismo , Tolcapona/química , Tolcapona/metabolismoRESUMEN
We previously reported 2-aminobenzoxazole analogue 1 as a potent ChemR23 inhibitor. The compound showed inhibitory activity against chemerin-induced calcium signaling through ChemR23 internalization in CAL-1 cells, which are cell lines of plasmacytoid dendric cells (pDCs). Furthermore, compound 2 inhibited chemotaxis of CAL-1 triggered by chemerin in vitro. However, we noted a difference in the ChemR23 response to our inhibitor between rodents and non-rodents in a previous study. To address this issue, we performed optimization of ChemR23 inhibitors using CAL-1 cells endogenously expressing human ChemR23 and conducted a pharmacokinetics study in cynomolgus monkeys. Various substituents at the 4-position of the benzoxazole ring exhibited potent in vitro bioactivity, while those at the 6-position were not tolerated. Among substituents, a carboxyl group was identified as key for improving the oral bioavailability in cynomolgus monkeys. Compound 38a with the acidic part changed from a tetrazole group to a 1,2,4-oxadiazol-5-one group to improve bioactivity and pharmacokinetic parameters exhibited inhibitory activity against chemerin-induced chemotaxis in vitro. In addition, we confirmed the ChemR23 internalization of pDCs by compound 38a orally administered to cynomolgus monkeys. These 2-aminobenzoxazole-based ChemR23 inhibitors may be useful as novel immunotherapeutic agents capable of suppressing the migration of pDCs, which are known to be major producers of type I interferons in the lesion area of certain autoimmune diseases, such as systemic lupus erythematosus and psoriasis.
Asunto(s)
Benzoxazoles/química , Diseño de Fármacos , Receptores de Quimiocina/antagonistas & inhibidores , Administración Oral , Animales , Benzoxazoles/administración & dosificación , Benzoxazoles/síntesis química , Benzoxazoles/metabolismo , Línea Celular , Células Dendríticas/citología , Células Dendríticas/metabolismo , Semivida , Humanos , Concentración 50 Inhibidora , Macaca fascicularis , Receptores de Quimiocina/metabolismo , Relación Estructura-Actividad , Tetrazoles/administración & dosificación , Tetrazoles/síntesis química , Tetrazoles/química , Tetrazoles/metabolismoRESUMEN
Pulsed radiofrequency (PRF) treatments for chronic pain consist in the delivery of a train of sinusoidal electric bursts to the targeted nerve. Despite numerous clinical evidence of its efficiency, the mechanism of action of PRF remains unclear. Since most of the reported biological effects of PRF can be initiated by a calcium influx into the neurons, we hypothesized that PRF may induce a mild electroporation effect causing a calcium uptake. To test this hypothesis, HEK-293 cells were exposed to PRF bursts and cytosolic calcium and Yo-Pro-1 uptake were monitored. After a single burst, calcium peaks were observed for electric fields above 480 V/cm while the uptake of Yo-pro-1 was insignificant. After a train of 120 bursts, the electric fields required to induce a calcium and Yo-pro-1 uptake decreased to 330 V/cm and 880 V/cm respectively. Calcium peaks were not detected when cells were treated in calcium free media. The temperature increase during the treatments was lower than 5 °C in all cases. Finally, the cell response for different burst frequencies and extracellular media conductivities correlated with the induced transmembrane voltage calculated with a numerical model. Our results support the hypothesis of an electroporation mediated calcium influx.
Asunto(s)
Calcio/metabolismo , Dolor Crónico/terapia , Electroporación/métodos , Tratamiento de Radiofrecuencia Pulsada/métodos , Benzoxazoles/metabolismo , Dolor Crónico/metabolismo , Citosol/metabolismo , Células HEK293 , Humanos , Técnicas In Vitro , Potenciales de la Membrana , Neuronas/metabolismo , Compuestos de Quinolinio/metabolismo , TemperaturaRESUMEN
In vitro permeability and in vivo pharmacokinetics of pemafibrate were investigated in human intestinal and animal models untreated or pretreated with cyclosporine A or rifampicin to evaluate any drug interactions. Ratios of basal to apical apparent permeability (Papp) over apical to basal Papp in the presence of pH gradients decreased from 0.37 to 0.080 on rifampicin co-incubation, suggesting active transport of pemafibrate from basal to apical sides in intestinal models. Plasma concentrations of intravenously administered pemafibrate were enhanced moderately in control mice but only marginally in humanized-liver mice by oral pretreatment with rifampicin [an organic anion transporting polypeptide (OATP) 1B1 inhibitor] 1 h before the administration of pemafibrate. In three cynomolgus monkeys genotyped as wild-type OATP1B1 (2 homozygous and 1 heterozygous), oral dosing of cyclosporine A 4 h or rifampicin 1 h before pemafibrate administration significantly increased the areas under the plasma concentration-time curves (AUC) of intravenously administered pemafibrate by 4.9- and 7.4-fold, respectively. Plasma AUC values of three pemafibrate metabolites in cynomolgus monkeys were also increased by cyclosporine A or rifampicin. These results suggested that pemafibrate was actively uptaken in livers and rapidly cleared from plasma in cynomolgus monkeys; this rapid clearance was suppressible by OATP1B1 inhibitors.
Asunto(s)
Benzoxazoles/sangre , Butiratos/sangre , Ciclosporina/sangre , Hipolipemiantes/sangre , Transportador 1 de Anión Orgánico Específico del Hígado/genética , Rifampin/sangre , Animales , Benzoxazoles/administración & dosificación , Benzoxazoles/metabolismo , Butiratos/administración & dosificación , Butiratos/metabolismo , Células CACO-2 , Ciclosporina/administración & dosificación , Ciclosporina/metabolismo , Genotipo , Humanos , Hipolipemiantes/administración & dosificación , Hipolipemiantes/metabolismo , Inyecciones Intravenosas , Transportador 1 de Anión Orgánico Específico del Hígado/metabolismo , Macaca fascicularis , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Rifampin/administración & dosificación , Rifampin/metabolismoRESUMEN
2-Mercaptobenzoxazole is a widely used organic scaffold in medicinal chemistry. By means of kinetic and structural studies, we demonstrate that this molecule can effectively be used to inhibit hCAs showing a peculiar binding mode. The results reported here can pave the way for the development of selective CA inhibitors.
Asunto(s)
Benzoxazoles/química , Inhibidores de Anhidrasa Carbónica/química , Anhidrasas Carbónicas/metabolismo , Compuestos de Sulfhidrilo/química , Secuencia de Aminoácidos , Benzoxazoles/metabolismo , Inhibidores de Anhidrasa Carbónica/metabolismo , Dominio Catalítico , Humanos , Cinética , Modelos Moleculares , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/metabolismoRESUMEN
Screening of a GSK-proprietary library against intracellular Mycobacterium tuberculosis identified 1, a thioalkylbenzoxazole hit. Biological profiling and mutant analysis revealed that this compound is a prodrug that is bioactivated by the mycobacterial enzyme MymA. A hit-expansion program including design, synthesis, and profiling of a defined set of analogues with optimized drug-like properties led to the identification of an emerging lead compound, displaying potency against intracellular bacteria in the low micromolar range, high in vitro solubility and permeability, and excellent microsomal stability.
Asunto(s)
Antituberculosos/farmacología , Proteínas Bacterianas/metabolismo , Benzoxazoles/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Oxigenasas/metabolismo , Profármacos/farmacología , Animales , Antituberculosos/síntesis química , Antituberculosos/metabolismo , Benzoxazoles/síntesis química , Benzoxazoles/metabolismo , Línea Celular Tumoral , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Microsomas Hepáticos/efectos de los fármacos , Estructura Molecular , Profármacos/síntesis química , Profármacos/metabolismo , Relación Estructura-ActividadRESUMEN
Transthyretin (TTR) modulates the deposition, processing, and toxicity of Abeta (Aß) peptides. We have shown that this effect is enhanced in mice by treatment with small molecules such as iododiflunisal (IDIF, 4), a good TTR stabilizer. Here, we describe the thermodynamics of the formation of binary and ternary complexes among TTR, Aß(1-42) peptide, and TTR stabilizers using isothermal titration calorimetry (ITC). A TTR/Aß(1-42) (1:1) complex with a dissociation constant of Kd = 0.94 µM is formed; with IDIF (4), this constant improves up to Kd = 0.32 µM, indicating the presence of a ternary complex TTR/IDIF/Aß(1-42). However, with the drugs diflunisal (1) or Tafamidis (2), an analogous chaperoning effect could not be observed. Similar phenomena could be recorded with the shorter peptide Aß(12-28) (7). We propose the design of a simple assay system for the search of other chaperones that behave like IDIF and may become potential candidate drugs for Alzheimer's disease (AD).
Asunto(s)
Péptidos beta-Amiloides/metabolismo , Benzoxazoles/metabolismo , Diflunisal/análogos & derivados , Diflunisal/metabolismo , Fragmentos de Péptidos/metabolismo , Prealbúmina/metabolismo , Multimerización de Proteína/efectos de los fármacos , Bioensayo/métodos , Calorimetría/métodos , Humanos , TermodinámicaRESUMEN
AIMS: Lipopolysaccharide (LPS)-induced intestinal injury is a common clinical feature of sepsis. Aggravated inflammation and higher sensitivity to infection are associated with high-fat diet (HFD) in patients with type 2 diabetes and/or obesity. However, the mechanism by which HFD exacerbates LPS-induced intestinal injury has not been elucidated. This study aims to examine the effects of HFD on intestinal injury induced by LPS and the underlying mechanism. MAIN METHODS: Mice were fed with HFD or regular chow for 12weeks and were then challenged with LPS. Vas2870 was administered to mice that received HFD before the initiation of the diet. The levels of tight junction protein expression, oxidative stress, organ injury, and nicotinamide adenine dinucleotide phosphate (NADPH)-associated proteins were assessed periodically. KEY FINDINGS: LPS treatment resulted in severe intestinal pathological injury and increased oxidative stress, evidenced by significantly increased serum diamine oxidase, reactive oxygen species, malondialdehyde, and intestinal fatty acid binding protein contents. Additionally, a decrease in tight junction protein expression was observed, indicating a loss of tight junction integrity. LPS treatment induced the expression of Nox2 and Nox4. All the effects were more severe in HFD mice. Treatment with vas2870 conferred protection against LPS-induced intestinal injury in HFD-fed mice, partially reduced oxidative stress, and rescued the expression of tight junction proteins. CONCLUSION: HFD aggravated LPS-induced intestine injury through exacerbating intestinal Nox-related oxidative stress, which led to a loss of the integrity of tight junctions and consequently increased intestinal permeability.
Asunto(s)
Dieta Alta en Grasa , Intestinos/efectos de los fármacos , Lipopolisacáridos/metabolismo , NADP/metabolismo , Estrés Oxidativo/efectos de los fármacos , Adsorción , Animales , Benzoxazoles/administración & dosificación , Benzoxazoles/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Proteínas de Unión a Ácidos Grasos/metabolismo , Humanos , Masculino , Malondialdehído/metabolismo , Ratones , Ratones Endogámicos C57BL , NADPH Oxidasas/metabolismo , Obesidad/metabolismo , Oxidación-Reducción , Permeabilidad , Especies Reactivas de Oxígeno/metabolismo , Proteínas de Uniones Estrechas/metabolismo , Uniones Estrechas/metabolismo , Triazoles/administración & dosificación , Triazoles/metabolismoRESUMEN
Malaria remains a major public health problem. With the loss of antimalarials to resistance, the malaria burden will likely continue for decades. New antimalarial scaffolds are crucial to avoid cross-resistance. Here, we present the first structure based virtual screening using the ß-haematin crystal as a target for new inhibitor scaffolds by applying a docking method. The ZINC15 database was searched for compounds with high binding affinity with the surface of the ß-haematin crystal using the PyRx Virtual Screening Tool. Top-ranked compounds predicted to interact with ß-haematin were submitted to a second screen applying in silico toxicity and drug-likeness predictions using Osiris DataWarrior. Fifteen compounds were purchased for experimental testing. An NP-40 mediated ß-haematin inhibition assay and parasite growth inhibition activity assay were performed. The benzoxazole moiety was found to be a promising scaffold for further development, showing intraparasitic haemozoin inhibition using a cellular haem fractionation assay causing a decrease in haemozoin in a dose dependent manner with a corresponding increase in exchangeable haem. A ß-haematin inhibition hit rate of 73% was found, a large enrichment over random screening, demonstrating that virtual screening can be a useful and cost-effective approach in the search for new haemozoin inhibiting antimalarials.
Asunto(s)
Antimaláricos/farmacología , Hemoproteínas/antagonistas & inhibidores , Plasmodium falciparum/efectos de los fármacos , Proteínas Protozoarias/antagonistas & inhibidores , Animales , Antimaláricos/química , Antimaláricos/metabolismo , Benzoxazoles/química , Benzoxazoles/metabolismo , Benzoxazoles/farmacología , Sitios de Unión , Células CHO , Supervivencia Celular/efectos de los fármacos , Cricetinae , Cricetulus , Bases de Datos de Proteínas , Hemoproteínas/metabolismo , Simulación del Acoplamiento Molecular , Conformación Proteica , Proteínas Protozoarias/metabolismoRESUMEN
This paper focuses on the production of a high-affinity monoclonal antibody (mAb) that can efficiently detect and block purinergic ligand-gated ion channel 7 receptor (P2X7R). To achieve this goal, the extracellular domain of human P2X7R, P2X7R-ECD, was used as an immunogen for BALB/c mice, inducing them to produce spleen lymphocytes that were subsequently fused with myeloma cells. Screening of the resultant hybridoma clones resulted in the selection of one stable positive clone that produced a qualified mAb, named 4B3A4. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis demonstrated that the purity of the purified 4B3A4 mAb was above 85%, with prominent bands corresponding to molecular weights of 55 kDa (heavy chain) and 25 kDa (light chain), and the BCA assay showed that the concentration of the purified 4B3A4 mAb was 0.3 mg/mL. Western blot analysis revealed that the 4B3A4 mAb could specifically recognize and bind both P2X7R-ECD and the full-length P2X7R protein. Laser scanning confocal microscopy (LSCM) revealed that the 4B3A4 mAb specifically bound to P2X7R on the membrane of human peripheral blood mononuclear cells (PBMCs). P2X7R expression was significantly different between healthy individuals and people with certain cancers as determined by flow cytometry (FCM). In addition, the 4B3A4 mAb significantly reduced ATP-stimulated Ca2+ entry and YO-PRO-1 uptake, which indicated that the 4B3A4 mAb effectively blocked P2X7R activity. These data indicate that the 4B3A4 mAb can be further used as not only an antibody to detect cell surface P2X7R but also as a therapeutic antibody to target P2X7R-related signaling pathways.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Receptores Purinérgicos P2X7/inmunología , Animales , Anticuerpos Monoclonales/química , Especificidad de Anticuerpos , Benzoxazoles/metabolismo , Calcio/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Femenino , Humanos , Inmunoglobulina G/química , Inmunoglobulina G/inmunología , Leucocitos Mononucleares/metabolismo , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Dominios Proteicos , Compuestos de Quinolinio/metabolismo , Receptores Purinérgicos P2X7/químicaRESUMEN
Gout is a crystalline-related arthropathy caused by the deposition of monosodium urate (MSU). Acute gouty arthritis is the most common first symptom of gout. Studies have shown that NOD-like receptor protein 3 (NLRP3) inflammasome as pattern recognition receptors can be activated by uric acid crystallization, triggering immune inflammation and causing acute gouty arthritis symptoms. Currently, the treatment of gout mainly includes two basic methods: reducing uric acid and alleviating inflammation. In this paper, 22 novel benzoxazole and benzimidazole derivatives were synthesized from deoxybenzoin oxime derivatives. These compounds have good inhibitory effects on NLRP3 and XOD screened by our research group in the early stage. The inhibitory activities of XOD and NLRP3 and their derivatives were also screened. Notably, compound 9b is a multi-targeting inhibitor of NLRP3 and XOD with excellent potency in treating hyperuricemia and acute gouty arthritis.
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Bencimidazoles/química , Benzoxazoles/química , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Xantina Oxidasa/antagonistas & inhibidores , Animales , Bencimidazoles/metabolismo , Bencimidazoles/farmacología , Bencimidazoles/uso terapéutico , Benzoxazoles/metabolismo , Benzoxazoles/farmacología , Benzoxazoles/uso terapéutico , Línea Celular , Modelos Animales de Enfermedad , Gota/tratamiento farmacológico , Gota/patología , Humanos , Hiperuricemia/tratamiento farmacológico , Interleucina-1beta/metabolismo , Hígado/enzimología , Ratones , Monocitos/citología , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Ácido Oxónico/farmacología , Ratas , Relación Estructura-Actividad , Membrana Sinovial/efectos de los fármacos , Membrana Sinovial/metabolismo , Ácido Úrico/sangre , Xantina Oxidasa/metabolismoRESUMEN
Heterocycles, a class of molecules that includes oxazoles, constitute one of the most common building blocks in current pharmaceuticals and are common in medicinally important natural products. The antitumor natural product nataxazole is a model for a large class of benzoxazole-containing molecules that are made by a pathway that is not characterized. We report structural, biochemical, and chemical evidence that benzoxazole biosynthesis proceeds through an ester generated by an ATP-dependent adenylating enzyme. The ester rearranges via a tetrahedral hemiorthoamide to yield an amide, which is a shunt product and not, as previously thought, an intermediate in the pathway. A second zinc-dependent enzyme catalyzes the formation of hemiorthoamide from the ester but, by shuttling protons, the enzyme eliminates water, a reverse hydrolysis reaction, to yield the benzoxazole and avoids the amide. These insights have allowed us to harness the pathway to synthesize a series of novel halogenated benzoxazoles.
Asunto(s)
Benzoxazoles/química , Benzoxazoles/metabolismo , Ésteres/química , Adenosina Trifosfato/metabolismo , Enzimas/química , Enzimas/metabolismo , Halogenación , Modelos Moleculares , Conformación ProteicaRESUMEN
PURPOSE OF REVIEW: Reduction of serum low-density lipoprotein cholesterol (LDL-C) levels by statins, ezetimibe and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors has been shown to significantly reduce cardiovascular events risk. However, fasting and postprandial hypertriglyceridemia as well as reduced high-density lipoprotein cholesterol (HDL-C) remain as residual risk factors of atherosclerotic cardiovascular diseases (ASCVD). To treat patients with hypertriglyceridemia and/or low HDL-C, drugs such as fibrates, nicotinic acids, and n-3 polyunsaturated fatty acids have been used. However, fibrates were demonstrated to cause side effects such as liver dysfunction and increase in creatinine levels, and thus large-scale clinical trials of fibrates have shown negative results for prevention of ASCVD. The failure could be attributed to their low selectivity and potency for binding to peroxisome proliferator-activated receptor (PPAR) α. To resolve these issues, the concept of selective PPARα modulator (SPPARMα) with a superior balance of efficacy and safety has been proposed and pemafibrate (K-877) has been developed. RECENT FINDINGS: Pemafibrate, one of SPPARMsα, was synthesized by Kowa Company, Ltd. for better efficiency and safety. Clinical trials in Japan have established the superiority of pemafibrate on effects on serum triglycerides (TG) reduction and HDL-C elevation as well safety. Although available fibrates showed worsening of liver and kidney function test values, pemafibrate indicated improved liver function test values and was less likely to increase serum creatinine or decrease estimated glomerular filtration rate (eGFR). Very few drug-drug interactions were observed even when used concomitantly with statins. Furthermore, pemafibrate is metabolized in the liver and excreted into the bile, while many of available fibrates are mainly excreted from the kidney. Therefore, pemafibrate can be used safely even in patients with impaired renal function since there is no significant increase in its blood concentration. A large-scale trial of pemafibrate, PROMINENT, for dyslipidemic patients with type 2 diabetes is ongoing. Pemafibrate is one of novel SPPARMsα and has superior benefit-risk balance compared to conventional fibrates and can be applicable for patients for whom the usage of existing fibrates is difficult such as those who are taking statins or patients with renal dysfunction. In the current review, all the recent data on pemafibrate will be summarized.