RESUMEN
Gepotidacin is a novel triazaacenaphthylene bacterial topoisomerase inhibitor. In this phase 1, nonrandomized, open-label, parallel-group, multicenter, multipart study, the pharmacokinetics, safety, and tolerability of a single intravenous (IV) dose of gepotidacin 750 mg over 2 hours were evaluated in subjects with normal renal function, in those with moderate and severe renal impairment, and in end-stage renal disease (ESRD) on and not on dialysis. Administration of IV gepotidacin 750 mg was safe and generally tolerated in the study subjects. Dosing in severe renal impairment with and without hemodialysis resulted in significant increases in plasma drug levels and decreases in clearance. The geometric mean elimination half-life (t½ ) was minimally impacted (range 9.45 to 11.5 hours) in all the renal-impairment groups relative to normal renal function. Regardless of renal function, urine gepotidacin concentrations remained considerably high over a 12-hour period. Saliva concentrations displayed a linear relationship with plasma concentrations. The t½ in saliva was not impacted in the moderate-impairment and ESRD subjects and was comparable to t½ in plasma. Over a 4-hour dialysis, approximately 6% of the gepotidacin dose was removed. Overall, subjects with severe renal impairment and ESRD with and without hemodialysis may require adjustment in dose or dosing frequency.
Asunto(s)
Acenaftenos/farmacocinética , Compuestos Heterocíclicos con 3 Anillos/farmacocinética , Fallo Renal Crónico/metabolismo , Insuficiencia Renal/metabolismo , Inhibidores de Topoisomerasa/farmacocinética , Acenaftenos/administración & dosificación , Acenaftenos/sangre , Administración Intravenosa , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Compuestos Heterocíclicos con 3 Anillos/administración & dosificación , Compuestos Heterocíclicos con 3 Anillos/sangre , Humanos , Fallo Renal Crónico/tratamiento farmacológico , Fallo Renal Crónico/fisiopatología , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados no Aleatorios como Asunto/métodos , Farmacocinética , Insuficiencia Renal/tratamiento farmacológico , Insuficiencia Renal/fisiopatología , Seguridad , Saliva/metabolismo , Inhibidores de Topoisomerasa/administración & dosificación , Inhibidores de Topoisomerasa/sangreRESUMEN
BACKGROUND: Cystic echinococcosis (CE), a condition caused by the larval stage of the dog tapeworm Echinococcus granulosus sensu stricto, is a globally distributed zoonotic disease. Current treatment options for CE are limited, and an effective and safe anti-echinococcal drug is urgently required. METHODS: Drug repurposing strategy was employed to identify new therapeutic agents against echinococcal cysts. An in vitro protoscolicidal assay along with in vivo murine models was applied in the drug screening. A microinjection procedure was employed to mimic the clinical PAIR (puncture, aspiration, injection and reaspiration) technique to evaluate the potential application of the candidate drug in clinical practice. FINDINGS: We repurposed pyronaridine, an approved antimalarial drug, for the treatment of CE. Following a three-dose intraperitoneal regimen (57 mg/kg, q.d. for 3 days), pyronaridine caused 100% cyst mortality. Oral administration of pyronaridine at 57 mg/kg, q.d. for 30 days significantly reduced the parasitic burden in the pre-infected mice compared with albendazole group (p < 0.001). Using a microinjection of drug into cysts, pyronaridine (200 µM) showed highly effective in term of inhibition of cyst growth (p < 0.05, compared with saline group). Pharmacokinetic analysis revealed that pyronaridine was highly distributed in the liver and lungs, the most affected organs of CE. Function analysis showed that pyronaridine inhibited the activity of topoisomerase I (IC50 = 209.7 ± 1.1 µM). In addition, classical apoptotic hallmarks, including DNA fragmentation and caspase activation, were triggered. INTERPRETATION: Given its approved clinical safety, the repurposing of pyronaridine offers a rapidly translational option for treating CE including PAIR. FUND: National Natural Science Foundation of China and International Cooperation Project of the Qinghai Science and Technology Department.
Asunto(s)
Antimaláricos/uso terapéutico , Equinococosis/tratamiento farmacológico , Naftiridinas/uso terapéutico , Inhibidores de Topoisomerasa/uso terapéutico , Animales , Antimaláricos/administración & dosificación , Antimaláricos/farmacocinética , Antimaláricos/toxicidad , Fragmentación del ADN , ADN-Topoisomerasas de Tipo I/metabolismo , Reposicionamiento de Medicamentos , Echinococcus granulosus/efectos de los fármacos , Echinococcus granulosus/patogenicidad , Femenino , Hígado/metabolismo , Hígado/parasitología , Pulmón/metabolismo , Pulmón/parasitología , Ratones , Ratones Endogámicos BALB C , Naftiridinas/administración & dosificación , Naftiridinas/farmacocinética , Naftiridinas/toxicidad , Distribución Tisular , Inhibidores de Topoisomerasa/administración & dosificación , Inhibidores de Topoisomerasa/farmacocinética , Inhibidores de Topoisomerasa/toxicidadRESUMEN
In our quest for new antibiotics able to address the growing threat of multidrug resistant infections caused by Gram-negative bacteria, we have investigated an unprecedented series of non-quinolone bacterial topoisomerase inhibitors from the Sanofi patrimony, named IPYs for imidazopyrazinones, as part of the Innovative Medicines Initiative (IMI) European Gram Negative Antibacterial Engine (ENABLE) organization. Hybridization of these historical compounds with the quinazolinediones, a known series of topoisomerase inhibitors, led us to a novel series of tricyclic IPYs that demonstrated potential for broad spectrum activity, in vivo efficacy, and a good developability profile, although later profiling revealed a genotoxicity risk. Resistance studies revealed partial cross-resistance with fluoroquinolones (FQs) suggesting that IPYs bind to the same region of bacterial topoisomerases as FQs and interact with at least some of the keys residues involved in FQ binding.
Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Imidazoles/farmacología , Pirazinas/farmacología , Quinazolinonas/farmacología , Inhibidores de Topoisomerasa/farmacología , Animales , Antibacterianos/síntesis química , Antibacterianos/farmacocinética , Antibacterianos/toxicidad , Farmacorresistencia Bacteriana/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Células Hep G2 , Humanos , Imidazoles/síntesis química , Imidazoles/farmacocinética , Imidazoles/toxicidad , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , Pirazinas/síntesis química , Pirazinas/farmacocinética , Pirazinas/toxicidad , Quinazolinonas/síntesis química , Quinazolinonas/farmacocinética , Quinazolinonas/toxicidad , Inhibidores de Topoisomerasa/síntesis química , Inhibidores de Topoisomerasa/farmacocinética , Inhibidores de Topoisomerasa/toxicidadRESUMEN
1. ETX0914 is a novel bacterial topoisomerase inhibitor that has a novel mode-of-inhibition and is in clinical development for the treatment of infections caused by Neisseria gonorrhoeae. 2. The in vitro biotransformation studies of ETX0914 using mouse, rat, dog and human hepatocytes showed moderate intrinsic clearance in mouse and rat and low intrinsic clearance in dog and human. 3. Following intravenous administration of [14C]-ETX0914 in rats, the mean recovery of administered dose in urine, bile and feces was approximately 15%, 55% and 24%, respectively. Unchanged ETX0914 recovered in urine and bile was less than 5% of the dose, indicating that ETX0914 underwent extensive metabolism in rats. Metabolites M1, M2, M4, M6 and M12 detected in both rat and mouse urine samples were not detected in mouse urine when predosed with 1-aminobenzotriazole, indicating that these metabolites were cytochrome P450 mediated products. The major fecal metabolites observed in rats were not formed when ETX0914 was incubated with fresh feces from germ free rats under sterile condition or in incubations with rat intestinal microsome and cytosol, suggesting that most likely ETX0914 was directly excreted into gut lumen where metabolites were formed as intestinal microflora-mediated products. The major sites of metabolism by CYP enzymes were in the morpholine and oxazolidinone rings while it was benzisoxazole reduction with the gut microflora.
Asunto(s)
Barbitúricos/farmacocinética , Compuestos de Espiro/farmacocinética , Inhibidores de Topoisomerasa/farmacocinética , Animales , ADN-Topoisomerasas de Tipo II/metabolismo , Perros , Humanos , Isoxazoles , Ratones , Morfolinas , Oxazolidinonas , RatasRESUMEN
ACT-387042 and ACT-292706 are two novel bacterial topoisomerase inhibitors with broad-spectrum activity against Gram-positive and -negative bacteria, including methicillin-resistant Staphylococcus aureus and penicillin- and fluoroquinolone-resistant Streptococcus pneumoniae We used the neutropenic murine thigh infection model to characterize the pharmacokinetics (PK)/pharmacodynamics (PD) of these investigational compounds against a group of 10 S. aureus and S. pneumoniae isolates with phenotypic resistance to beta-lactams and fluoroquinolones. The in vitro activities of the two compounds were very similar (MIC range, 0.03 to 0.125 mg/liter). Plasma pharmacokinetics were determined for each compound by using four escalating doses administered by the subcutaneous route. In treatment studies, mice had 10(7.4) to 10(8) CFU/thigh at the start of therapy with ACT-387042 and 10(6.7) to 10(8.3) CFU/thigh at the start of therapy with ACT-292706. A dose-response relationship was observed with all isolates over the dose range. Maximal kill approached 3 to 4 log10 CFU/thigh compared to the burden at the start of therapy for the highest doses examined. There was a strong relationship between the PK/PD index AUC/MIC ratio (area under the concentration-time curve over 24 h in the steady state divided by the MIC) and therapeutic efficacy in the model (R(2), 0.63 to 0.82). The 24-h free-drug AUC/MIC ratios associated with net stasis for ACT-387042 against S. aureus and S. pneumoniae were 43 and 10, respectively. The 24-h free-drug AUC/MIC ratios associated with net stasis for ACT-292706 against S. aureus and S. pneumoniae were 69 and 25, respectively. The stasis PD targets were significantly lower for S. pneumoniae (P < 0.05) for both compounds. The 1-log-kill AUC/MIC ratio targets were â¼2- to 4-fold higher than stasis targets. Methicillin, penicillin, or ciprofloxacin resistance did not alter the magnitude of the AUC/MIC ratio required for efficacy. These results should be helpful in the design of clinical trials for topoisomerase inhibitors.
Asunto(s)
Antibacterianos/farmacocinética , Naftiridinas/farmacocinética , Neutropenia/tratamiento farmacológico , Infecciones Neumocócicas/tratamiento farmacológico , Piranos/farmacocinética , Piridazinas/farmacocinética , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Infecciones Estafilocócicas/tratamiento farmacológico , Inhibidores de Topoisomerasa/farmacocinética , Animales , Antibacterianos/sangre , Antibacterianos/farmacología , Área Bajo la Curva , Esquema de Medicación , Cálculo de Dosificación de Drogas , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Femenino , Inyecciones Subcutáneas , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Ratones , Ratones Endogámicos ICR , Pruebas de Sensibilidad Microbiana , Naftiridinas/sangre , Naftiridinas/farmacología , Neutropenia/sangre , Neutropenia/microbiología , Neutropenia/patología , Infecciones Neumocócicas/sangre , Infecciones Neumocócicas/microbiología , Infecciones Neumocócicas/patología , Piranos/sangre , Piranos/farmacología , Piridazinas/sangre , Piridazinas/farmacología , Infecciones de los Tejidos Blandos/sangre , Infecciones de los Tejidos Blandos/microbiología , Infecciones de los Tejidos Blandos/patología , Infecciones Estafilocócicas/sangre , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/patología , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/crecimiento & desarrollo , Muslo/microbiología , Muslo/patología , Inhibidores de Topoisomerasa/sangre , Inhibidores de Topoisomerasa/farmacologíaRESUMEN
Topoisomerases (Topo I and II) have been looked as crucial targets against various types of cancers. In the present paper, 100 anticancerous alkaloids were subjected to in silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) analyses to investigate their pharmacokinetic properties. Out of 100 alkaloids, only 18 were found to fulfill all the ADMET descriptors and obeyed the Lipinski's rule of five. All the 18 alkaloids were found to dock successfully within the active site of both Topo I and II. A comparison of the inhibitory potential of 18 screened alkaloids with those of selected drugs revealed that four alkaloids (oliveroline, coptisine, aristolactam, and piperine) inhibited Topo I, whereas six alkaloids (oliveroline, aristolactam, anonaine, piperine, coptisine, and liriodenine) inhibited Topo II more strongly than those of their corresponding drugs, topotecan and etoposide, respectively, with oliveroline being the outstanding. The stability of the complexes of Topo I and II with the best docked alkaloid, oliveroline, was further analyzed using 10 nSec molecular dynamics simulation and compared with those of the respective drugs, namely, topotecan and etoposide, which revealed stabilization of these complexes within 5 nSec of simulation with better stability of Topo II complex than that of Topo I.
Asunto(s)
Alcaloides/química , Alcaloides/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Inhibidores de Topoisomerasa/química , Inhibidores de Topoisomerasa/farmacología , Alcaloides/farmacocinética , Animales , Antineoplásicos/farmacocinética , Barrera Hematoencefálica/metabolismo , ADN-Topoisomerasas de Tipo I/metabolismo , Humanos , Absorción Intestinal , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Inhibidores de Topoisomerasa/farmacocinéticaRESUMEN
Gemifloxacin mesylate (GFM) is a synthetic, broad-spectrum, fluoroquinolone antibacterial agent. It is different from other class members because it achieves adequate plasma concentrations to inhibit both topoisomerase IV and gyrase. The aim of this study was to develop and validate a dissolution test for GFM in coated tablets, using a simulated absorption profile based on in vivo data obtained from the literature. The fraction and percentage of the dose absorbed were calculated using model-dependent Loo-Riegelman approach for two compartments. The best in vitro dissolution profile was obtained using 900 mL of pH 6.0 phosphate buffer as a dissolution medium at 37 °C ± 0.5 °C and paddles at 50 rpm. The in vitro dissolution samples were analyzed using a liquid chromatography method, and the validation was performed according to USP 34 (2011). The method showed specificity, precision, accuracy, robustness and linearity. Under these conditions, a level-A in vitro-in vivo correlation was suggested (r = 0.9926). The prediction errors were calculated to determine the validity and accuracy of the suggested correlation. The dissolution test can be used to evaluate the dissolution profile of GFM-coated tablets and minimize the number of bioavailability studies as part of new formulation development.
Asunto(s)
Antibacterianos/química , Industria Farmacéutica/métodos , Fluoroquinolonas/química , Absorción Intestinal , Modelos Biológicos , Naftiridinas/química , Inhibidores de Topoisomerasa/química , Animales , Antibacterianos/análisis , Antibacterianos/sangre , Antibacterianos/farmacocinética , Disponibilidad Biológica , Brasil , Cromatografía Líquida de Alta Presión , Simulación por Computador , Industria Farmacéutica/instrumentación , Liberación de Fármacos , Fluoroquinolonas/análisis , Fluoroquinolonas/sangre , Fluoroquinolonas/farmacocinética , Gemifloxacina , Humanos , Concentración de Iones de Hidrógeno , Modelos Lineales , Naftiridinas/análisis , Naftiridinas/sangre , Naftiridinas/farmacocinética , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta , Comprimidos Recubiertos , Inhibidores de Topoisomerasa/análisis , Inhibidores de Topoisomerasa/sangre , Inhibidores de Topoisomerasa/farmacocinéticaRESUMEN
1. (2R,4S,4aS)-11-Fluoro-2,4-dimethyl-8-((S)-4-methyl-2-oxooxazolidin-3-yl)-2,4,4a,6-tetrahydro-1H,1'H-spiro [isoxazolo[4,5-g][1,4]oxazino[4,3-a]quinoline-5,5'-pyrimidine]-2',4',6'(3'H)-trione (AZ11) is a novel mode-of-inhibition bacterial topoisomerase inhibitor that entered preclinical development for the treatment of Gram-positive bacteria infection. 2. The in vitro biotransformation studies of AZ11 using mouse, rat, dog and human hepatocytes showed low-intrinsic clearance in all species attributed to microsomal metabolism. 3. After a single intravenous administration of [14C]AZ11 in bile duct cannulated rats, the mean percentage of dose recovered in rat urine, bile and feces was approximately 18, 36 and 42%, respectively. Unchanged AZ11 recovered in rat urine and bile was less than 9% of the dose, indicating that AZ11 underwent extensive metabolism in rats. 4. The most abundant in vivo metabolite detected in urine and bile was M1 formed via ring opening on the piperidine and morpholine rings accounting for 20% of the administered dose. The major fecal metabolite was M5, which accounted for approximately 32% of administered dose. M5 was not formed when AZ11 incubated with rat intestinal microsomes and cytosol but was formed when incubated with fresh rat feces, suggesting that unchanged AZ11 was directly excreted into gut lumen where M5 formed as an intestinal microflora-mediated product. This process could have significant impact on bioavailability or exposure of AZ11 in rat.
Asunto(s)
Barbitúricos/farmacocinética , Girasa de ADN/farmacocinética , Hepatocitos/metabolismo , Compuestos de Espiro/farmacocinética , Inhibidores de Topoisomerasa/farmacocinética , Animales , Barbitúricos/química , Biotransformación , Girasa de ADN/química , Perros , Humanos , Mucosa Intestinal/metabolismo , Ratones , Microsomas/metabolismo , Ratas , Compuestos de Espiro/química , Inhibidores de Topoisomerasa/químicaRESUMEN
A series of chiral Ru(II) complexes bearing thiophene ligands were synthesized and characterized. Both Ru(II) complexes Δ/Λ-[Ru(bpy)2(pscl)](2+) (Δ/Λ-1) and Δ/Λ-[Ru(bpy)2(psbr)](2+) (Δ/Λ-2) (bpy=2,2'-bipyridine, pscl=2-(5-chlorothiophen-2-yl)imidazo[4,5-f][1,10]phenanthroline, psbr=2-(5-bromothiophen-2-yl)imidazo[4,5-f][1,10]phenanthroline) showed antitumor activities against A549, HepG2 and BEL-7402 tumor cell lines, especially HeLa tumor cell line. Moreover, Δ enantiomers were more active than Λ enantiomers, accounting for the different cellular uptake. In addition, with the extension of time, these enantiomers could finally accumulate in the nucleus, suggesting that nucleic acids were the cellular target of these enantiomers. The DNA-binding behaviors of complexes were studied using spectroscopic and viscosity measurements. Results suggested that four complexes could bind to DNA in an intercalative mode but no obvious DNA-binding selectivity between the enantiomers was observed. Topoisomerase inhibition and DNA religation assay confirmed that four complexes acted as efficient dual topoisomerase I and II poisons, DNA strand breaks had also been observed from alkaline single cell gel electrophoresis (comet assay). Δ-1 and Δ-2 inhibited the growth of HeLa cells through the induction of apoptotic cell death, as evidenced by the Alexa Fluor® 488 annexin V staining assays and flow cytometry analysis. The results demonstrated that Δ/Λ-1 and Δ/Λ-2 acted as dual topoisomerase I and II poisons and caused DNA damage that could lead to cell cycle arrest by apoptosis.
Asunto(s)
Compuestos Organometálicos/química , Compuestos Organometálicos/farmacología , Rutenio/química , Inhibidores de Topoisomerasa/química , Inhibidores de Topoisomerasa/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , ADN/metabolismo , Células HeLa/efectos de los fármacos , Humanos , Estructura Molecular , Compuestos Organometálicos/síntesis química , Fenantrolinas/química , Rutenio/metabolismo , Inhibidores de Topoisomerasa I/química , Inhibidores de Topoisomerasa I/farmacología , Inhibidores de Topoisomerasa II/química , Inhibidores de Topoisomerasa II/farmacología , Inhibidores de Topoisomerasa/síntesis química , Inhibidores de Topoisomerasa/farmacocinéticaRESUMEN
Enrofloxacin is a fluorquinolone exclusively developed for use in veterinary medicine (1980). The kinetics of enrofloxacin are characterized, in general terms, by high bioavailability in most species and rapid absorption after IM, SC or oral administration. However, several studies reported that enrofloxacin showed low bioavailability after oral administration in ruminants. This drug has a broad distribution in the organism, excellent tissue penetration and long serum half-life. Also, enrofloxacin is characterized by a low host toxicity, a broad antibacterial spectrum and high bactericidal activity against major pathogenic bacteria (both Gram-positive and Gram-negative), and intracellular organisms found in diseased animals. The kinetics vary according to the route of administration, formulation, animal species, age, body condition, and physiological status, all of which contribute to differences in drug efficacy. The pharmacokinetic properties of drugs are closely related to their pharmacological efficiency, so it is important to know their behavior in each species that is used. This article reviews the pharmacokinetics of enrofloxacin in several domestic animal species.
Asunto(s)
Antibacterianos/farmacocinética , Fluoroquinolonas/farmacocinética , Animales , Animales Domésticos , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/metabolismo , Infecciones Bacterianas/veterinaria , Disponibilidad Biológica , Biotransformación , Enrofloxacina , Fluoroquinolonas/administración & dosificación , Fluoroquinolonas/efectos adversos , Fluoroquinolonas/uso terapéutico , Semivida , Humanos , Absorción Intestinal , Tasa de Depuración Metabólica , Distribución Tisular , Inhibidores de Topoisomerasa/administración & dosificación , Inhibidores de Topoisomerasa/efectos adversos , Inhibidores de Topoisomerasa/farmacocinética , Inhibidores de Topoisomerasa/uso terapéuticoRESUMEN
The type II topoisomerases DNA gyrase (GyrA/GyrB) and topoisomerase IV (ParC/ParE) are well-validated targets for antibacterial drug discovery. Because of their structural and functional homology, these enzymes are amenable to dual targeting by a single ligand. In this study, two novel benzothiazole ethyl urea-based small molecules, designated compound A and compound B, were evaluated for their biochemical, antibacterial, and pharmacokinetic properties. The two compounds inhibited the ATPase activity of GyrB and ParE with 50% inhibitory concentrations of <0.1 µg/ml. Prevention of DNA supercoiling by DNA gyrase was also observed. Both compounds potently inhibited the growth of a range of bacterial organisms, including staphylococci, streptococci, enterococci, Clostridium difficile, and selected Gram-negative respiratory pathogens. MIC90s against clinical isolates ranged from 0.015 µg/ml for Streptococcus pneumoniae to 0.25 µg/ml for Staphylococcus aureus. No cross-resistance with common drug resistance phenotypes was observed. In addition, no synergistic or antagonistic interactions between compound A or compound B and other antibiotics, including the topoisomerase inhibitors novobiocin and levofloxacin, were detected in checkerboard experiments. The frequencies of spontaneous resistance for S. aureus were <2.3 × 10(-10) with compound A and <5.8 × 10(-11) with compound B at concentrations equivalent to 8× the MICs. These values indicate a multitargeting mechanism of action. The pharmacokinetic properties of both compounds were profiled in rats. Following intravenous administration, compound B showed approximately 3-fold improvement over compound A in terms of both clearance and the area under the concentration-time curve. The measured oral bioavailability of compound B was 47.7%.
Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Benzotiazoles/farmacología , Topoisomerasa de ADN IV/antagonistas & inhibidores , ADN-Topoisomerasas de Tipo II/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Inhibidores de Topoisomerasa/farmacología , Urea/análogos & derivados , Adenosina Trifosfatasas/antagonistas & inhibidores , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Animales , Antibacterianos/química , Antibacterianos/farmacocinética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Benzotiazoles/química , Benzotiazoles/farmacocinética , Supervivencia Celular/efectos de los fármacos , Topoisomerasa de ADN IV/genética , Topoisomerasa de ADN IV/metabolismo , ADN-Topoisomerasas de Tipo II/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Bacterias Gramnegativas/enzimología , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/enzimología , Bacterias Grampositivas/crecimiento & desarrollo , Células Hep G2 , Humanos , Interleucina-33 , Interleucinas , Levofloxacino/farmacología , Masculino , Pruebas de Sensibilidad Microbiana , Novobiocina/farmacología , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Inhibidores de Topoisomerasa/química , Inhibidores de Topoisomerasa/farmacocinética , Urea/química , Urea/farmacocinética , Urea/farmacologíaRESUMEN
There is an urgent need for new antibacterial drugs that are effective against infections caused by multidrug-resistant pathogens. Novel nonfluoroquinolone inhibitors of bacterial type II topoisomerases (DNA gyrase and topoisomerase IV) have the potential to become such drugs because they display potent antibacterial activity and exhibit no target-mediated cross-resistance with fluoroquinolones. Bacterial topoisomerase inhibitors that are built on a tetrahydropyran ring linked to a bicyclic aromatic moiety through a syn-diol linker show potent anti-Gram-positive activity, covering isolates with clinically relevant resistance phenotypes. For instance, analog 49c was found to be a dual DNA gyrase-topoisomerase IV inhibitor, with broad antibacterial activity and low propensity for spontaneous resistance development, but suffered from high hERG K(+) channel block. On the other hand, analog 49e displayed lower hERG K(+) channel block while retaining potent in vitro antibacterial activity and acceptable frequency for resistance development. Furthermore, analog 49e showed moderate clearance in rat and promising in vivo efficacy against Staphylococcus aureus in a murine infection model.
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Antibacterianos/síntesis química , Antibacterianos/farmacología , ADN-Topoisomerasas/metabolismo , Diseño de Fármacos , Bacterias Grampositivas/efectos de los fármacos , Piranos/síntesis química , Piranos/farmacología , Animales , Antibacterianos/metabolismo , Antibacterianos/farmacocinética , Técnicas de Química Sintética , Girasa de ADN/química , Girasa de ADN/metabolismo , Topoisomerasa de ADN IV/antagonistas & inhibidores , Topoisomerasa de ADN IV/química , Topoisomerasa de ADN IV/metabolismo , ADN-Topoisomerasas/química , Femenino , Bacterias Grampositivas/enzimología , Humanos , Concentración 50 Inhibidora , Ratones , Simulación del Acoplamiento Molecular , Conformación Proteica , Piranos/metabolismo , Piranos/farmacocinética , Ratas , Relación Estructura-Actividad , Inhibidores de Topoisomerasa II , Inhibidores de Topoisomerasa/síntesis química , Inhibidores de Topoisomerasa/metabolismo , Inhibidores de Topoisomerasa/farmacocinética , Inhibidores de Topoisomerasa/farmacologíaRESUMEN
Angelman syndrome is a severe neurodevelopmental disorder caused by deletion or mutation of the maternal allele of the ubiquitin protein ligase E3A (UBE3A). In neurons, the paternal allele of UBE3A is intact but epigenetically silenced, raising the possibility that Angelman syndrome could be treated by activating this silenced allele to restore functional UBE3A protein. Using an unbiased, high-content screen in primary cortical neurons from mice, we identify twelve topoisomerase I inhibitors and four topoisomerase II inhibitors that unsilence the paternal Ube3a allele. These drugs included topotecan, irinotecan, etoposide and dexrazoxane (ICRF-187). At nanomolar concentrations, topotecan upregulated catalytically active UBE3A in neurons from maternal Ube3a-null mice. Topotecan concomitantly downregulated expression of the Ube3a antisense transcript that overlaps the paternal copy of Ube3a. These results indicate that topotecan unsilences Ube3a in cis by reducing transcription of an imprinted antisense RNA. When administered in vivo, topotecan unsilenced the paternal Ube3a allele in several regions of the nervous system, including neurons in the hippocampus, neocortex, striatum, cerebellum and spinal cord. Paternal expression of Ube3a remained elevated in a subset of spinal cord neurons for at least 12 weeks after cessation of topotecan treatment, indicating that transient topoisomerase inhibition can have enduring effects on gene expression. Although potential off-target effects remain to be investigated, our findings suggest a therapeutic strategy for reactivating the functional but dormant allele of Ube3a in patients with Angelman syndrome.
Asunto(s)
Alelos , Silenciador del Gen/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Inhibidores de Topoisomerasa/farmacología , Ubiquitina-Proteína Ligasas/genética , Síndrome de Angelman/tratamiento farmacológico , Síndrome de Angelman/genética , Animales , Células Cultivadas , Corteza Cerebral/citología , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Evaluación Preclínica de Medicamentos , Padre , Femenino , Impresión Genómica/efectos de los fármacos , Impresión Genómica/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Madres , Bibliotecas de Moléculas Pequeñas/administración & dosificación , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Inhibidores de Topoisomerasa/administración & dosificación , Inhibidores de Topoisomerasa/análisis , Inhibidores de Topoisomerasa/farmacocinética , Topotecan/administración & dosificación , Topotecan/farmacocinética , Topotecan/farmacología , Ubiquitina-Proteína Ligasas/deficienciaRESUMEN
Novel non-fluoroquinolone inhibitors of bacterial type II topoisomerases (DNA gyrase and topoisomerase IV) are of interest for the development of new antibacterial agents that are not impacted by target-mediated cross-resistance with fluoroquinolones. Aminopiperidines that have a bicyclic aromatic moiety linked through a carbon to an ethyl bridge, such as 1, generally show potent broad-spectrum antibacterial activity, including quinolone-resistant isolates, but suffer from potent hERG inhibition (IC(50)= 3 µM for 1). We now disclose the finding that new analogues of 1 with an N-linked cyclic amide moiety attached to the ethyl bridge, such as 24m, retain the broad-spectrum antibacterial activity of 1 but show significantly less hERG inhibition (IC(50)= 31 µM for 24m) and higher free fraction than 1. One optimized analogue, compound 24l, showed moderate clearance in the dog and promising efficacy against Staphylococcus aureus in a mouse thigh infection model.