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1.
Eur J Med Chem ; 264: 115946, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38043491

RESUMEN

Pteridine reductase 1 (PTR1) is a catalytic protein belonging to the folate metabolic pathway in Trypanosmatidic parasites. PTR1 is a known target for the medicinal chemistry development of antiparasitic agents against Trypanosomiasis and Leishmaniasis. In previous studies, new nitro derivatives were elaborated as PTR1 inhibitors. The compounds showing a diamino-pyrimidine core structure were previously developed but they showed limited efficacy. Therefore, a new class of phenyl-, heteroaryl- and benzyloxy-nitro derivatives based on the 2-nitroethyl-2,4,6-triaminopyrimidine scaffold were designed and tested. The compounds were assayed for their ability to inhibit T. brucei and L. major PTR1 enzymes and for their antiparasitic activity towards T. brucei and L. infantum parasites. To understand the structure-activity relationships of the compounds against TbPTR1, the X-ray crystallographic structure of the 2,4,6-triaminopyrimidine (TAP) was obtained and molecular modelling studies were performed. As a next step, only the most effective compounds against T. brucei were then tested against the amastigote cellular stage of T. cruzi, searching for a broad-spectrum antiprotozoal agent. An early ADME-Tox profile evaluation was performed. The early toxicity profile of this class of compounds was investigated by measuring their inhibition of hERG and five cytochrome P450 isoforms (CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4), cytotoxicity towards A549 cells and mitochondrial toxicity. Pharmacokinetic studies (SNAP-PK) were performed on selected compounds using hydroxypropyl-ß-cyclodextrins (50 % w/v) to preliminarily study their plasma concentration when administered per os at a dose of 20 mg/kg. Compound 1p, showed the best pharmacodynamic and pharmacokinetic properties, can be considered a good candidate for further bioavailability and efficacy studies.


Asunto(s)
Antiprotozoarios , Enfermedad de Chagas , Trypanosoma brucei brucei , Trypanosoma cruzi , Humanos , Relación Estructura-Actividad , Antiprotozoarios/química , Modelos Moleculares , Antiparasitarios/farmacología , Enfermedad de Chagas/tratamiento farmacológico
2.
Elife ; 112022 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-36475542

RESUMEN

Drugs that target human thymidylate synthase (hTS), a dimeric enzyme, are widely used in anticancer therapy. However, treatment with classical substrate-site-directed TS inhibitors induces over-expression of this protein and development of drug resistance. We thus pursued an alternative strategy that led us to the discovery of TS-dimer destabilizers. These compounds bind at the monomer-monomer interface and shift the dimerization equilibrium of both the recombinant and the intracellular protein toward the inactive monomers. A structural, spectroscopic, and kinetic investigation has provided evidence and quantitative information on the effects of the interaction of these small molecules with hTS. Focusing on the best among them, E7, we have shown that it inhibits hTS in cancer cells and accelerates its proteasomal degradation, thus causing a decrease in the enzyme intracellular level. E7 also showed a superior anticancer profile to fluorouracil in a mouse model of human pancreatic and ovarian cancer. Thus, over sixty years after the discovery of the first TS prodrug inhibitor, fluorouracil, E7 breaks the link between TS inhibition and enhanced expression in response, providing a strategy to fight drug-resistant cancers.


Asunto(s)
Neoplasias Ováricas , Timidilato Sintasa , Femenino , Animales , Ratones , Humanos , Sitios de Unión , Timidilato Sintasa/química , Timidilato Sintasa/metabolismo , Fluorouracilo/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología
3.
Nanomaterials (Basel) ; 10(3)2020 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-32245153

RESUMEN

The active targeting to alveolar macrophages (AM) is an attractive strategy to improve the therapeutic efficacy of 'old' drugs currently used in clinical practice for the treatment of pulmonary tuberculosis. Previous studies highlighted the ability of respirable solid lipid nanoparticle assemblies (SLNas), loaded with rifampicin (RIF) and functionalized with a novel synthesized mannose-based surfactant (MS), both alone and in a blend with sodium taurocholate, to efficiently target the AM via mannose receptor-mediated mechanism. Here, we present the in vivo biodistribution of these mannosylated SLNas, in comparison with the behavior of both non-functionalized SLNas and bare RIF. SLNas biodistribution was assessed, after intratracheal instillation in mice, by whole-body real-time fluorescence imaging in living animals and RIF quantification in excised organs and plasma. Additionally, SLNas cell uptake was determined by using fluorescence microscopy on AM from bronchoalveolar lavage fluid and alveolar epithelium from lung dissections. Finally, histopathological evaluation was performed on lungs 24 h after administration. SLNas functionalized with MS alone generated the highest retention in lungs associated with a poor spreading in extra-pulmonary regions. This effect could be probably due to a greater AM phagocytosis with respect to SLNas devoid of mannose on their surface. The results obtained pointed out the unique ability of the nanoparticle surface decoration to provide a potential more efficient treatment restricted to the lungs where the primary tuberculosis infection is located.

4.
Pharmaceutics ; 11(10)2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31581554

RESUMEN

The mimicking of physiological conditions is crucial for the success of accurate in vitro studies. For inhaled nanoparticles, which are designed for being deposited on alveolar epithelium and taken up by macrophages, it is relevant to investigate the interactions with pulmonary surfactant lining alveoli. As a matter of fact, the formation of a lipid corona layer around the nanoparticles could modulate the cell internalization and the fate of the transported drugs. Based on this concept, the present research focused on the interactions between pulmonary surfactant and Solid Lipid Nanoparticle assemblies (SLNas), loaded with rifampicin, an anti-tuberculosis drug. SLNas were functionalized with a synthesized mannosylated surfactant, both alone and in a blend with sodium taurocholate, to achieve an active targeting to mannose receptors present on alveolar macrophages (AM). Physico-chemical properties of the mannosylated SLNas satisfied the requirements relative to suitable respirability, drug payload, and AM active targeting. Our studies have shown that a lipid corona is formed around SLNas in the presence of Curosurf, a commercial substitute of the natural pulmonary surfactant. The lipid corona promoted an additional resistance to the drug diffusion for SLNas functionalized with the mannosylated surfactant and this improved drug retention within SLNas before AM phagocytosis takes place. Moreover, lipid corona formation did not modify the role of nanoparticle mannosylation towards the specific receptors on MH-S cell membrane.

5.
Eur J Med Chem ; 183: 111676, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31542713

RESUMEN

Leishmaniasis, a major health problem worldwide, has a limited arsenal of drugs for its control. The appearance of resistance to first- and second-line anti-leishmanial drugs confirms the need to develop new and less toxic drugs that overcome spontaneous resistance. In the present study, we report the design and synthesis of a novel library of 38 flavonol-like compounds and their evaluation in a panel of assays encompassing parasite killing, pharmacokinetics, genomics and ADME-Toxicity resulting in the progression of a compound in the drug discovery value chain. Compound 19, 2-(benzo[b]thiophen-3-yl)-3-hydroxy-6-methoxy-4H-chromen-4-one, exhibited a broad-spectrum activity against Leishmania spp. (EC50 1.9 µM for Leishmania infantum, 3.4 µM for L. donovani, 6.7 µM for L. major), Trypanosoma cruzi (EC50 7.5 µM) and T. brucei (EC50 0.8 µM). Focusing on anti-Leishmania activity, compound 19 challenge in vitro did not select for resistance markers in L. donovani, while a Cos-Seq screening for dominant resistance genes identified a gene locus on chromosome 36 that became ineffective at concentrations beyond EC50. Thus, compound 19 is a promising scaffold to tackle drug resistance in Leishmania infection. In vivo pharmacokinetic studies indicated that compound 19 has a long half-life (intravenous (IV): 63.2 h; per os (PO): 46.9 h) with an acceptable ADME-Toxicity profile. When tested in Leishmania infected hamsters, no toxicity and limited efficacy were observed. Low solubility and degradation were investigated spectroscopically as possible causes for the sub-optimal pharmacokinetic properties. Compound 19 resulted a specific compound based on the screening against a protein set, following the intrinsic fluorescence changes.


Asunto(s)
Antiprotozoarios , Flavonoles , Leishmania/efectos de los fármacos , Leishmaniasis/tratamiento farmacológico , Fosforilcolina/análogos & derivados , Tiofenos , Animales , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Antiprotozoarios/farmacología , Cricetinae , Evaluación Preclínica de Medicamentos , Resistencia a Medicamentos/efectos de los fármacos , Flavonoles/síntesis química , Flavonoles/química , Flavonoles/farmacología , Genómica , Humanos , Fosforilcolina/química , Fosforilcolina/farmacología , Tiofenos/síntesis química , Tiofenos/química , Tiofenos/farmacología
6.
ACS Med Chem Lett ; 10(4): 528-533, 2019 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-30996791

RESUMEN

Chemical modulation of the flavonol 2-(benzo[d][1,3]dioxol-5-yl)-chromen-4-one (1), a promising anti-Trypanosomatid agent previously identified, was evaluated through a phenotypic screening approach. Herein, we have performed structure-activity relationship studies around hit compound 1. The pivaloyl derivative (13) showed significant anti-T. brucei activity (EC50 = 1.1 µM) together with a selectivity index higher than 92. The early in vitro ADME-tox properties (cytotoxicity, mitochondrial toxicity, cytochrome P450 and hERG inhibition) were determined for compound 1 and its derivatives, and these led to the identification of some liabilities. The 1,3-benzodioxole moiety in the presented compounds confers better in vivo pharmacokinetic properties than those of classical flavonols. Further studies using different delivery systems could lead to an increase of compound blood levels.

7.
J Med Chem ; 62(8): 3989-4012, 2019 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-30908048

RESUMEN

2-Amino-benzo[ d]thiazole was identified as a new scaffold for the development of improved pteridine reductase-1 (PTR1) inhibitors and anti-trypanosomatidic agents. Molecular docking and crystallography guided the design and synthesis of 42 new benzothiazoles. The compounds were assessed for Trypanosoma brucei and Leishmania major PTR1 inhibition and in vitro activity against T. brucei and amastigote Leishmania infantum. We identified several 2-amino-benzo[ d]thiazoles with improved enzymatic activity ( TbPTR1 IC50 = 0.35 µM; LmPTR1 IC50 = 1.9 µM) and low µM antiparasitic activity against T. brucei. The ten most active compounds against TbPTR1 were able to potentiate the antiparasitic activity of methotrexate when evaluated in combination against T. brucei, with a potentiating index between 1.2 and 2.7. The compound library was profiled for early ADME toxicity, and 2-amino- N-benzylbenzo[ d]thiazole-6-carboxamide (4c) was finally identified as a novel potent, safe, and selective anti-trypanocydal agent (EC50 = 7.0 µM). Formulation of 4c with hydroxypropyl-ß-cyclodextrin yielded good oral bioavailability, encouraging progression to in vivo studies.


Asunto(s)
Antiprotozoarios/química , Benzotiazoles/química , Inhibidores Enzimáticos/química , Leishmania major/enzimología , Oxidorreductasas/antagonistas & inhibidores , Proteínas Protozoarias/antagonistas & inhibidores , Trypanosoma brucei brucei/enzimología , Animales , Antiprotozoarios/metabolismo , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Benzotiazoles/metabolismo , Benzotiazoles/farmacología , Benzotiazoles/uso terapéutico , Sitios de Unión , Dominio Catalítico , Cristalografía por Rayos X , Diseño de Fármacos , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Semivida , Leishmania major/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Simulación del Acoplamiento Molecular , Oxidorreductasas/metabolismo , Proteínas Protozoarias/metabolismo , Relación Estructura-Actividad , Trypanosoma brucei brucei/efectos de los fármacos , Tripanosomiasis/tratamiento farmacológico , Tripanosomiasis/patología
8.
Curr Top Med Chem ; 19(9): 646-661, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30827246

RESUMEN

Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), still remains an urgent global health issue, mainly due to the emergence of multi-drug resistant strains. Therefore, there is a pressing need to develop novel and more efficient drugs to control the disease. In this context, targeting the pathogen virulence factors, and particularly signal mechanisms, seems to be a promising approach. An important transmembrane signaling system in Mtb is represented by receptor-type Serine/ Threonine protein kinases (STPKs). Mtb has 11 different STPKs, two of them, PknA and PknB, are essential. By contrast PknG and PknH are involved in Mtb virulence and adaptation, and are fundamental for the pathogen growth in infection models. Therefore, STPKs represent a very interesting group of pharmacological targets in M. tuberculosis. In this work, the principal inhibitors of the mycobacterial STPKs will be presented and discussed. In particular, medicinal chemistry efforts have been focused on discovering new antimycobacterial compounds, targeting three of these kinases, namely PknA, PknB and PknG. Generally, the inhibitory effect on these enzymes do not correlate with a significant antimycobacterial action in whole-cell assays. However, compounds with activity in the low micromolar range have been obtained, demonstrating that targeting Mtb STPKs could be a new promising strategy for the development of drugs to treat TB infections.


Asunto(s)
Antituberculosos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Antituberculosos/química , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Mycobacterium tuberculosis/metabolismo , Inhibidores de Proteínas Quinasas/química , Proteínas Serina-Treonina Quinasas/metabolismo
9.
J Enzyme Inhib Med Chem ; 34(1): 823-828, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30889995

RESUMEN

Starting from the analysis of the hypothetical binding mode of our previous furan-based hit (I), we successfully achieved our objective to replace the nitro moiety, leading to the disclosure of a new lead exhibiting a strong activity against MbtI. Our best candidate 1 h displayed a Ki of 8.8 µM and its antimycobacterial activity (MIC99 = 250 µM) is conceivably related to mycobactin biosynthesis inhibition. These results support the hypothesis that 5-phenylfuran-2-carboxylic derivatives are a promising class of MbtI inhibitors.


Asunto(s)
Antituberculosos/química , Antituberculosos/farmacología , Inhibidores Enzimáticos/farmacología , Furanos/química , Liasas/antagonistas & inhibidores , Sitios de Unión , Inhibidores Enzimáticos/química , Liasas/química , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Mycobacterium bovis/efectos de los fármacos , Relación Estructura-Actividad
10.
J Colloid Interface Sci ; 541: 399-406, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30710822

RESUMEN

With the aim of developing new drug carriers for inhalation therapy, we report here an in depth investigation of the structure of multilamellar liposomes loaded with two well-established anti-tubercular (anti-TB) drugs, isoniazid (INH) and rifampicin (RIF), by means of small-angle neutron-scattering (SANS) analysis. Unloaded, single drug-loaded and co-loaded liposomes were prepared using different amounts of drugs and characterized regarding size, encapsulation efficiency and drug release. Detailed information on relevant properties of the investigated host-guest structures, namely the steric bilayer thickness, particle dispersion, number of lamellae and drug localization was studied by SANS. Results showed that RIF-liposomes were less ordered than unloaded liposomes. INH induced a change in the inter-bilayer periodical spacing, while RIF-INH co-loading stabilized the multilamellar liposome architecture, as confirmed by the increment of the drug loading capacity. These findings could be useful for the understanding of in vitro and in vivo behavior of these systems and for the design of new drug carriers, intended for inhaled therapy.


Asunto(s)
Antituberculosos/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Isoniazida/química , Liposomas/química , Rifampin/química , Dispersión del Ángulo Pequeño
11.
Drug Deliv Transl Res ; 9(1): 298-310, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30484257

RESUMEN

The present study reports about new solid lipid nanoparticle assemblies (SLNas) loaded with rifampicin (RIF) surface-decorated with novel mannose derivatives, designed for anti-tuberculosis (TB) inhaled therapy by dry powder inhaler (DPI). Mannose is considered a relevant ligand to achieve active drug targeting being mannose receptors (MR) overexpressed on membranes of infected alveolar macrophages (AM), which are the preferred site of Mycobacterium tuberculosis. Surface decoration of SLNas was obtained by means of newly synthesized functionalizing compounds used as surfactants in the preparation of carriers. SLNas were fully characterized in vitro determining size, morphology, drug loading, drug release, surface mannosylation, cytotoxicity, macrophage internalization extent and ability to bind MR, and intracellular RIF concentration. Moreover, the influence of these new surface functionalizing agents on SLNas aerodynamic performance was assessed by measuring particle respirability features using next generation impactor. SLNas exhibited suitable drug payload, in vitro release, and more efficient ability to enter macrophages (about 80%) compared to bare RIF (about 20%) and to non-functionalized SLNas (about 40%). The involvement of MR-specific binding has been demonstrated by saturating MR of J774 cells causing a decrease of RIF intracellular concentration of about 40%. Furthermore, it is noteworthy that the surface decoration of particles produced a poor cohesive powder with an adequate respirability (fine particle fraction ranging from about 30 to 50%). Therefore, the proposed SLNas may represent an encouraging opportunity in a perspective of an efficacious anti-TB inhaled therapy.


Asunto(s)
Antibióticos Antituberculosos/farmacología , Lectinas Tipo C/metabolismo , Macrófagos/microbiología , Lectinas de Unión a Manosa/metabolismo , Manosa/química , Receptores de Superficie Celular/metabolismo , Rifampin/farmacología , Animales , Antibióticos Antituberculosos/química , Línea Celular , Liberación de Fármacos , Inhaladores de Polvo Seco , Femenino , Macrófagos/metabolismo , Receptor de Manosa , Ratones , Mycobacterium tuberculosis/efectos de los fármacos , Nanopartículas/química , Rifampin/química , Propiedades de Superficie , Tensoactivos
12.
Eur J Med Chem ; 155: 754-763, 2018 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-29940465

RESUMEN

We report on the virtual screening, synthesis, and biological evaluation of new furan derivatives targeting Mycobacterium tuberculosis salicylate synthase (MbtI). A receptor-based virtual screening procedure was applied to screen the Enamine database, identifying two compounds, I and III, endowed with a good enzyme inhibitory activity. Considering the most active compound I as starting point for the development of novel MbtI inhibitors, we obtained new derivatives based on the furan scaffold. Among the SAR performed on this class, compound 1a emerged as the most potent MbtI inhibitor reported to date (Ki = 5.3 µM). Moreover, compound 1a showed a promising antimycobacterial activity (MIC99 = 156 µM), which is conceivably related to mycobactin biosynthesis inhibition.


Asunto(s)
Antituberculosos/farmacología , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Liasas/antagonistas & inhibidores , Mycobacterium tuberculosis/efectos de los fármacos , Antituberculosos/síntesis química , Antituberculosos/química , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Liasas/metabolismo , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Mycobacterium tuberculosis/enzimología , Relación Estructura-Actividad
13.
Molecules ; 23(7)2018 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-29933627

RESUMEN

Tuberculosis is the leading cause of death from a single infectious agent worldwide; therefore, the need for new antitubercular drugs is desperate. The recently validated target salicylate synthase MbtI is the first enzyme involved in the biosynthesis of mycobactins, compounds able to chelate iron, an essential cofactor for the survival of Mycobacterium tuberculosis in the host. Here, we report on the synthesis and biological evaluation of chromane-based compounds as new potential inhibitors of MbtI. Our approach successfully allowed the identification of a novel lead compound (1), endowed with a promising activity against this enzyme (IC50 = 55 µM). Molecular modeling studies were performed in order to evaluate the binding mode of 1 and rationalize the preliminary structure-activity relationships, thus providing crucial information to carry out further optimization studies.


Asunto(s)
Antituberculosos/química , Proteínas Bacterianas/antagonistas & inhibidores , Ácido Corísmico/química , Cromanos/química , Inhibidores Enzimáticos/química , Liasas/antagonistas & inhibidores , Mycobacterium tuberculosis/química , Secuencias de Aminoácidos , Antituberculosos/síntesis química , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Dominio Catalítico , Ácido Corísmico/metabolismo , Cromanos/síntesis química , Inhibidores Enzimáticos/síntesis química , Expresión Génica , Cinética , Liasas/química , Liasas/genética , Liasas/metabolismo , Simulación del Acoplamiento Molecular , Mycobacterium tuberculosis/enzimología , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Relación Estructura-Actividad , Especificidad por Sustrato , Termodinámica
14.
Eur J Med Chem ; 146: 423-434, 2018 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-29407968

RESUMEN

Basing on a library of thiadiazole derivatives showing anti-trypanosomatidic activity, we have considered the thiadiazoles opened forms and reaction intermediates, thiosemicarbazones, as compounds of interest for phenotypic screening against Trypanosoma brucei (Tb), intracellular amastigote form of Leishmania infantum (Li) and Trypanosoma cruzi (Tc). Similar compounds have already shown interesting activity against the same organisms. The compounds were particularly effective against T. brucei and T. cruzi. Among the 28 synthesized compounds, the best one was (E)-2-(4-((3.4-dichlorobenzyl)oxy)benzylidene) hydrazinecarbothioamide (A14) yielding a comparable anti-parasitic activity against the three parasitic species (TbEC50 = 2.31 µM, LiEC50 = 6.14 µM, TcEC50 = 1.31 µM) and a Selectivity Index higher than 10 with respect to human macrophages, therefore showing a pan-anti-trypanosomatidic activity. (E)-2-((3'.4'-dimethoxy-[1.1'-biphenyl]-3-yl)methyle ne) hydrazinecarbothioamide (A12) and (E)-2-(4-((3.4-dichlorobenzyl)oxy)benzylidene)hydrazine carbothioamide (A14) were able to potentiate the anti-parasitic activity of methotrexate (MTX) when evaluated in combination against T. brucei, yielding a 6-fold and 4-fold respectively Dose Reduction Index for MTX. The toxicity profile against four human cell lines and a panel of in vitro early-toxicity assays (comprising hERG, Aurora B, five cytochrome P450 isoforms and mitochondrial toxicity) demonstrated the low toxicity for the thosemicarbazones class in comparison with known drugs. The results confirmed thiosemicarbazones as a suitable chemical scaffold with potential for the development of properly decorated new anti-parasitic drugs.


Asunto(s)
Antiprotozoarios/farmacología , Enfermedad de Chagas/tratamiento farmacológico , Tiosemicarbazonas/farmacología , Trypanosoma/efectos de los fármacos , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Relación Dosis-Respuesta a Droga , Humanos , Macrófagos/efectos de los fármacos , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Relación Estructura-Actividad , Tiosemicarbazonas/síntesis química , Tiosemicarbazonas/química
15.
Eur J Med Chem ; 146: p. 423-434, 2018.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib14932

RESUMEN

Basing on a library of thiadiazole derivatives showing anti-trypanosomatidic activity, we have considered the thiadiazoles opened forms and reaction intermediates, thiosemicarbazones, as compounds of interest for phenotypic screening against Trypanosoma brucei (Tb), intracellular amastigote form of Leishmania infantum (Li) and Trypanosoma cruzi (Tc). Similar compounds have already shown interesting activity against the same organisms. The compounds were particularly effective against T. brucei and T. cruzi. Among the 28 synthesized compounds, the best one was (E)-2-(4-((3.4-dichlorobenzyl)oxy)benzylidene) hydrazinecarbothioamide (A14) yielding a comparable anti-parasitic activity against the three parasitic species (TbEC50=231 mu M, LiEC50 = 6.14 mu M, TcEC50 = 1.31 mu M) and a Selectivity Index higher than 10 with respect to human macrophages, therefore showing a pan-anti-trypanosomatidic activity. (E)-2-((3'.4'-dimethoxy-[1.1'-biphenyl]-3-yl)methyle ne) hydrazinecarbothioamide (A12) and (E)-2-(4-((3.4-dichlorobenzyl)oxy)benzylidene)hydrazine carbothioamide (A14) were able to potentiate the anti parasitic activity of methotrexate (MTX) when evaluated in combination against T. brucei, yielding a 6 fold and 4-fold respectively Dose Reduction Index for MTX. The toxicity profile against four human cell lines and a panel of in vitro early-toxicity assays (comprising hERG, Aurora B, five cytochrome P450 isoforms and mitochondrial toxicity) demonstrated the low toxicity for the thosemicarbazones class in comparison with known drugs. The results confirmed thiosemicarbazones as a suitable chemical scaffold with potential for the development of properly decorated new anti-parasitic drugs.

16.
Eur J Med Chem, v. 146, p. 423-434, fev. 2018
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2419

RESUMEN

Basing on a library of thiadiazole derivatives showing anti-trypanosomatidic activity, we have considered the thiadiazoles opened forms and reaction intermediates, thiosemicarbazones, as compounds of interest for phenotypic screening against Trypanosoma brucei (Tb), intracellular amastigote form of Leishmania infantum (Li) and Trypanosoma cruzi (Tc). Similar compounds have already shown interesting activity against the same organisms. The compounds were particularly effective against T. brucei and T. cruzi. Among the 28 synthesized compounds, the best one was (E)-2-(4-((3.4-dichlorobenzyl)oxy)benzylidene) hydrazinecarbothioamide (A14) yielding a comparable anti-parasitic activity against the three parasitic species (TbEC50=231 mu M, LiEC50 = 6.14 mu M, TcEC50 = 1.31 mu M) and a Selectivity Index higher than 10 with respect to human macrophages, therefore showing a pan-anti-trypanosomatidic activity. (E)-2-((3'.4'-dimethoxy-[1.1'-biphenyl]-3-yl)methyle ne) hydrazinecarbothioamide (A12) and (E)-2-(4-((3.4-dichlorobenzyl)oxy)benzylidene)hydrazine carbothioamide (A14) were able to potentiate the anti parasitic activity of methotrexate (MTX) when evaluated in combination against T. brucei, yielding a 6 fold and 4-fold respectively Dose Reduction Index for MTX. The toxicity profile against four human cell lines and a panel of in vitro early-toxicity assays (comprising hERG, Aurora B, five cytochrome P450 isoforms and mitochondrial toxicity) demonstrated the low toxicity for the thosemicarbazones class in comparison with known drugs. The results confirmed thiosemicarbazones as a suitable chemical scaffold with potential for the development of properly decorated new anti-parasitic drugs.

17.
ACS Omega ; 2(9): 5666-5683, 2017 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-28983525

RESUMEN

Pteridine reductase-1 (PTR1) is a promising drug target for the treatment of trypanosomiasis. We investigated the potential of a previously identified class of thiadiazole inhibitors of Leishmania major PTR1 for activity against Trypanosoma brucei (Tb). We solved crystal structures of several TbPTR1-inhibitor complexes to guide the structure-based design of new thiadiazole derivatives. Subsequent synthesis and enzyme- and cell-based assays confirm new, mid-micromolar inhibitors of TbPTR1 with low toxicity. In particular, compound 4m, a biphenyl-thiadiazole-2,5-diamine with IC50 = 16 µM, was able to potentiate the antitrypanosomal activity of the dihydrofolate reductase inhibitor methotrexate (MTX) with a 4.1-fold decrease of the EC50 value. In addition, the antiparasitic activity of the combination of 4m and MTX was reversed by addition of folic acid. By adopting an efficient hit discovery platform, we demonstrate, using the 2-amino-1,3,4-thiadiazole scaffold, how a promising tool for the development of anti-T. brucei agents can be obtained.

18.
Int J Pharm ; 528(1-2): 440-451, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-28624659

RESUMEN

This study describes the development of new mannosylated Solid Lipid Nanoparticle assemblies (SLNas) delivering rifampicin for an inhaled treatment of tuberculosis. SLNas were surface engineered with mannose residues to recognize mannose receptors located on infected alveolar macrophages and facilitate cell internalization. Two sets of SLNas were produced by the melt emulsifying technique using biocompatible lipid components, i.e. cholesteryl myristate combined with palmitic acid (PA set) or tripalmitin (TP set), in the presence of the targeting moiety, methyl α-d-mannopyranoside. Mannosylated SLNas were examined for their physical properties, drug payloads and release, as well as respirability in terms of emitted dose and respirable fraction determined by Next Generation Impactor. The most appropriate formulations were assessed for mannosylation using FTIR, XPS, SEM coupled with EDX analysis, and wettability assay, in comparison with the respective non-functionalized SLNas. Besides, cytotoxicity and cell internalization ability were established on J774 murine macrophage cell line. Mannosylated SLNas exhibited physical properties suitable for alveolar macrophage passive targeting, adequate rifampicin payloads (10-15%), and feasible drug maintenance within SLNas along the respiratory tract before macrophage internalization. Despite respirability impaired by powder cohesiveness, surface mannosylation provided quicker macrophage phagocytosis, giving evidence of an active targeting promotion.


Asunto(s)
Sistemas de Liberación de Medicamentos , Lípidos/química , Macrófagos/efectos de los fármacos , Metilmanósidos/química , Nanopartículas/química , Tuberculosis/tratamiento farmacológico , Administración por Inhalación , Animales , Línea Celular , Manosa , Ratones , Fagocitosis , Terapia Respiratoria
19.
Ann Vasc Surg ; 42: 304.e11-304.e16, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28389292

RESUMEN

Type II endoleak is the most frequent procedure-related complication during endovascular aneurysm exclusion. Actually, there is little controversy in the management of type I and III endoleak, while type II endoleak still generates conflicting reports about their timing and type of treatment. Currently, the intervention is needed only in case of sac enlargement but not in case of persistent endoleak alone. We report the case of a 77-year-old man treated with a custom-made branched/fenestrated endograft for a type III thoracoabdominal aortic aneurysm. A low-flow type II endoleak was detected at the end of the intervention, and a conservative approach was adopted. The sixth month follow-up computed tomography scan demonstrated a 6-mm aneurysm sac growth that required the type II endoleak management. The endoleak nidus, situated between the inferior mesenteric artery (IMA) and left renal artery stent graft, was embolized through the IMA punctured laparoscopically. IMA origin laparoscopic clipping completed the intervention. To our knowledge, this is a unique case in the literature. Type II endoleak management should be reserved to selected patients. The combination of different techniques may offer safe and feasible treatment options in complex aneurysms treated with advanced endovascular materials.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Embolización Terapéutica/métodos , Endofuga/cirugía , Procedimientos Endovasculares/instrumentación , Laparoscopía , Stents , Anciano , Aortografía/métodos , Implantación de Prótesis Vascular/efectos adversos , Angiografía por Tomografía Computarizada , Endofuga/diagnóstico por imagen , Endofuga/etiología , Procedimientos Endovasculares/efectos adversos , Humanos , Masculino , Diseño de Prótesis , Resultado del Tratamiento
20.
Eur J Med Chem ; 126: 1129-1135, 2017 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-28064141

RESUMEN

Chalcones display a broad spectrum of pharmacological activities. Herein, a series of 2'-hydroxy methoxylated chalcones was synthesized and evaluated towards Trypanosoma brucei, Trypanosoma cruzi and Leishmania infantum. Among the synthesized library, compounds 1, 3, 4, 7 and 8 were the most potent and selective anti-T. brucei compounds (EC50 = 1.3-4.2 µM, selectivity index >10-fold). Compound 4 showed the best early-tox and antiparasitic profile. The pharmacokinetic studies of compound 4 in BALB/c mice using hydroxypropil-ß-cyclodextrins formulation showed a 7.5 times increase in oral bioavailability.


Asunto(s)
Antiparasitarios/química , Antiparasitarios/farmacología , Chalconas/química , Chalconas/farmacología , Animales , Antiparasitarios/farmacocinética , Antiparasitarios/toxicidad , Línea Celular Tumoral , Chalconas/farmacocinética , Chalconas/toxicidad , Ciclodextrinas/química , Portadores de Fármacos/química , Ratones , Solubilidad , Trypanosomatina/efectos de los fármacos
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