RESUMO
New 2,5- and 1,5-disubstituted tetrazoles, and 2,5-disubstituted-1,3,4-oxadiazoles were synthesized as tariquidar and elacridar derivatives and studied as multidrug resistance (MDR) reversers. Their behaviour on the three ABC transporters P-gp, MRP1 and BCRP was investigated. All compounds inhibited the P-gp transport activity in MDCK-MDR1 cells overexpressing P-gp, showing EC50 values even in the low nanomolar range (compounds 15, 22). Oxadiazole derivatives were able to increase the antiproliferative effect of doxorubicin in MDCK-MDR1 and in HT29/DX cells confirming their nature of P-gp modulators, with derivative 15 being the most potent in these assays. Compound 15 also displayed a dual inhibitory effect showing good activities towards both P-gp and BCRP. A computational study suggested a common interaction pattern on P-gp for most of the potent compounds. The bioisosteric substitution of the amide group of lead compounds allowed identifying a new set of potent oxadiazole derivatives that modulate MDR through inhibition of the P-gp efflux activity. If compared to previous amide derivatives, the introduction of the heterocycle rings greatly enhances the activity on P-gp, introduces in two compounds a moderate inhibitory activity on MRP1 and maintains in some cases the effect on BCRP, leading to the unveiling of dual inhibitor 15.
Assuntos
Antineoplásicos , Antineoplásicos/farmacologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Resistencia a Medicamentos Antineoplásicos , Relação Estrutura-Atividade , Proteínas de Neoplasias , Resistência a Múltiplos Medicamentos , Tetrazóis/farmacologia , Amidas/farmacologiaRESUMO
The tandem mass spectrometry (MS/MS) approach employing an ion trap mass analyzer (IT) was evaluated in isomers recognition. The proposed approach consists of sole, simple, and rapid liquid chromatographic separation (HPLC) without requiring resolution between the analytes. Then, the MS/MS properties were optimized to solve the signal assignment using post-processing data elaboration (LEDA). The IT-MS/MS experiment uses the same site, helium as collision gas, and different time steps to modify the applied conditions on the studied ions. Nevertheless, helium cannot ensure the quick energization of the precursor ion due to its small cross-section. Then, different combinations between excitation amplitude (ExA) and excitation time (ExT) were tested to achieve the activation of the fragmentation channels and the formation of the MS/MS spectrum. Usually, the IT-MS/MS acquisition cycle is longer for other multistage instruments, decreasing the frequency of sample data collection and influencing the chromatographic profile. To solve these problems, two time segments were set up, and the elution conditions were optimized with a compromise between peaks distinction and run time reduction. The developed HPLC-MS/MS method was checked and applied to analyze a series of human plasma samples spiked with an equimolar mixture of pair of isomers.
Assuntos
Hélio , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , AlgoritmosRESUMO
Tuberculosis treatment requires months-long combination chemotherapy with multiple drugs, with shorter treatments leading to relapses. A major impediment to shortening treatment is that Mycobacterium tuberculosis becomes tolerant to the administered drugs, starting early after infection and within days of infecting macrophages. Multiple lines of evidence suggest that macrophage-induced drug tolerance is mediated by mycobacterial drug efflux pumps. Here, using assays to directly measure drug efflux, we find that M. tuberculosis transports the first-line antitubercular drug rifampicin through a proton gradient-dependent mechanism. We show that verapamil, a known efflux pump inhibitor, which inhibits macrophage-induced rifampicin tolerance, also inhibits M.tuberculosis rifampicin efflux. As with macrophage-induced tolerance, the calcium channel-inhibiting property of verapamil is not required for its inhibition of rifampicin efflux. By testing verapamil analogs, we show that verapamil directly inhibits M. tuberculosis drug efflux pumps through its human P-glycoprotein (PGP)-like inhibitory activity. Screening commonly used drugs with incidental PGP inhibitory activity, we find many inhibit rifampicin efflux, including the proton pump inhibitors (PPIs) such as omeprazole. Like verapamil, the PPIs inhibit macrophage-induced rifampicin tolerance as well as intramacrophage growth, which has also been linked to mycobacterial efflux pump activity. Our assays provide a facile screening platform for M. tuberculosis efflux pump inhibitors that inhibit in vivo drug tolerance and growth.
Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Rifampina/farmacologia , Inibidores da Bomba de Prótons/farmacologia , Antituberculosos/farmacologia , Verapamil/farmacologia , Macrófagos , Tuberculose/tratamento farmacológico , Tolerância a Medicamentos , Proteínas de Bactérias , Testes de Sensibilidade MicrobianaRESUMO
Positive allosteric modulators (PAMs), negative allosteric modulators (NAMs), silent agonists, allosteric activating PAMs and neutral or silent allosteric modulators are compounds capable of modulating the nicotinic receptor by interacting at allosteric modulatory sites distinct from the orthosteric sites. This survey is focused on the compounds that have been shown or have been designed to interact with nicotinic receptors as allosteric modulators of different subtypes, mainly α7 and α4ß2. Minimal chemical changes can cause a different pharmacological profile, which can then lead to the design of selective modulators. Experimental evidence supports the use of allosteric modulators as therapeutic tools for neurological and non-neurological conditions.
Assuntos
Receptores Nicotínicos , Receptores Nicotínicos/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/química , Regulação Alostérica , Sítio AlostéricoRESUMO
Metformin is the most prescribed glucose-lowering drug worldwide; globally, over 100 million patients are prescribed this drug annually. Some different action mechanisms have been proposed for this drug, but, surprisingly, no metabolite of metformin has ever been described. It was considered interesting to investigate the possible reaction of metformin with glucose following the Maillard reaction pattern. The reaction was first performed in in vitro conditions, showing the formation of two adducts that originated by the condensation of the two molecular species with the losses of one or two water molecules. Their structures were investigated by liquid chromatography coupled with mass spectrometry (HPLC-MS), tandem mass spectrometry (MS/MS) and accurate mass measurements (HRMS). The species originated via the reaction of glucose and metformin and were called metformose and dehydrometformose, and some structural hypotheses were conducted. It is worth to emphasize that they were detected in urine samples from a diabetic patient treated with metformin and consequently they must be considered metabolites of the drug, which has never been identified before now. The glucose-related substructure of these compounds could reflect an improved transfer across cell membranes and, consequently, new hypotheses could be made about the biological targets of metformin.
Assuntos
Metformina , Humanos , Espectrometria de Massas em Tandem , Espectrometria de Massa com Cromatografia Líquida , Membrana Celular , GlucoseRESUMO
This paper proposes a tandem mass spectrometry (MS/MS) approach in isomer recognition by playing in the "energetic dimension" of the experiment. The chromatographic set up (HPLC) was tuned to minimize the run time, without requiring high efficiency or resolution between the isomers. Then, the MS/MS properties were explored to solve the signal assignment by performing a series of energy resolved experiments in order to optimize the parameters, and by applying an interesting post-processing data elaboration tool (LEDA). The reliability of the new approach was evaluated, determining the accuracy and precision of the quantitative results through analysis of the isomer mixture solutions. Next, the proposed method was applied in a chemical stability study of human plasma samples through the simultaneous addition of a pair of isomers. In the studied case, only one of the isomers suffered of enzymatic hydrolysis; therefore, the influence of the stable isomer on the degradation rate of the other was verified. In order to monitor this process correctly, it must be possible to distinguish each isomer present in the sample, quantify it, and plot its degradation profile. The reported results demonstrated the effectiveness of the LEDA algorithm in separating the isomers, without chromatographic resolution, and monitoring their behavior in human plasma samples.
Assuntos
Algoritmos , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , IsomerismoRESUMO
BACKGROUND: The failure of anticancer chemotherapy is often due to the development of resistance to a variety of anticancer drugs. This phenomenon is called multidrug resistance (MDR) and is related to the overexpression of ABC transporters, such as P-glycoprotein, multidrug resistance- associated protein 1 and breast cancer resistance protein. Over the past few decades, several ABC protein modulators have been discovered and studied as a possible approach to evade MDR and increase the success of anticancer chemotherapy. Nevertheless, the co-administration of pump inhibitors with cytotoxic drugs, which are substrates of the transporters, does not appear to be associated with an improvement in the therapeutic efficacy of antitumor agents. However, more recently discovered MDR reversing agents, such as the two tetrahydroisoquinoline derivatives tariquidar and elacridar, are characterized by high affinity towards the ABC proteins and by reduced negative properties. Consequently, many analogs of these two derivatives have been synthesized, with the aim of optimizing their MDR reversal properties. OBJECTIVE: This review aims to describe the MDR modulators carrying the tetraidroisoquinoline scaffold reported in the literature in the period 2009-2021, highlighting the structural characteristics that confer potency and/or selectivity towards the three ABC transport proteins. RESULTS AND CONCLUSION: Many compounds have been synthesized in the last twelve years showing interesting properties, both in terms of potency and selectivity. Although clear structure-activity relationships can be drawn only by considering strictly related compounds, some of the compounds reviewed could be promising starting points for the design of new ABC protein inhibitors.
Assuntos
Antineoplásicos , Neoplasias , Tetra-Hidroisoquinolinas , Humanos , Transportadores de Cassetes de Ligação de ATP , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Resistencia a Medicamentos Antineoplásicos , Proteínas de Neoplasias , Resistência a Múltiplos Medicamentos , Antineoplásicos/química , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Tetra-Hidroisoquinolinas/farmacologia , Neoplasias/tratamento farmacológicoRESUMO
In a continuing search of dual P-gp and hCA XII inhibitors, we synthesized and studied new N,N-bis(alkanol)amine aryl diester derivatives characterized by the presence of a coumarin group. These hybrids contain both P-gp and hCA XII binding groups to synergistically overcome the P-gp-mediated multidrug resistance (MDR) in cancer cells expressing both P-gp and hCA XII. Indeed, hCA XII modulates the efflux activity of P-gp and the inhibition of hCA XII reduces the intracellular pH, thereby decreasing the ATPase activity of P-gp. All compounds showed inhibitory activities on P-gp and hCA XII proteins taken individually, and many of them displayed a synergistic effect in HT29/DOX and A549/DOX cells that overexpress both P-gp and hCA XII, being more potent than in K562/DOX cells overexpressing only P-gp. Compounds 5 and 14 were identified as promising chemosensitizer agents for selective inhibition in MDR cancer cells overexpressing both P-gp and hCA XII.
Assuntos
Anidrases Carbônicas , Neoplasias , Humanos , Relação Estrutura-Atividade , Anidrases Carbônicas/metabolismo , Resistência a Múltiplos Medicamentos , Aminas/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Inibidores da Anidrase Carbônica/farmacologia , Inibidores da Anidrase Carbônica/química , Anidrase Carbônica IX , Antígenos de Neoplasias/metabolismo , Estrutura Molecular , Neoplasias/tratamento farmacológicoRESUMO
INTRODUCTION: Piperazine is a structural element present in drugs belonging to various chemical classes and used for numerous different therapeutic applications; it has been considered a privileged scaffold for drug design. AREAS COVERED: The authors have searched examples of piperazine-containing compounds among drugs recently approved by the FDA and in some research fields (nicotinic receptor modulators, compounds acting against cancer, and bacterial multidrug resistance), looking in particular to the design behind the insertion of this moiety. EXPERT OPINION: Piperazine is widely used due to its peculiar characteristics, such as solubility, basicity, chemical reactivity, and conformational properties. This moiety has represented an important tool to modulate pharmacokinetic and pharmacodynamic properties of drugs.
Assuntos
Neoplasias , Receptores Nicotínicos , Desenho de Fármacos , Descoberta de Drogas , Humanos , Piperazina/farmacologiaRESUMO
Design and synthesis of new candidate drugs produces a large number of compounds that must be qualified and tested to evaluate their characteristics and potential applications. Therefore, many studies will be scheduled and, consequently, it will be necessary to arrange specific, reliable, fast and relatively cheap analytic methods to support this research. The manuscript proposes a new approach in the HPLC-MS/MS analysis by using a sole chromatographic set up, tuned to minimize the run time, without requiring high efficiency or resolution between the analytes. The chromatographic column was used only to avoid or limit the interference of sample matrix towards the analyte ionization process (matrix-effects). Then, the MS/MS properties were explored to solve the signal assignment, by performing a series of energy resolved experiments to optimize the parameters and applying an interesting post-processing data elaboration tool (LEDA). The reliability of the new approach was evaluated in a chemical stability study in PBS and human plasma samples of a series of isomeric compounds P-glycoprotein/Carbonic Anhydrase (P-gp/CA) hybrid inhibitors. The obtained results demonstrated the effectiveness (reliability 97%-100%) of the LEDA algorithm to recognize and to separate the possible isomers present in the samples. The obtained matrix-effects values (ME 96%-106%) established that the chromatographic set up (short column and fast elution gradient) was proper to avoid the matrix interferences, while recovery values (RE 88%-108%) indicate a suitable sample preparation, despite only a protein precipitation was carried out. The quantitative performances of proposed HPLC-MS/MS methods showed an accuracy ranging between 92% and 108% and a precision lower than 13% that allows to be confident on the determination of new P-gp/CA hybrid inhibitors in the degradation study. Therefore, the general procedure proposed was found adequate to study a series of isomeric compounds without their chromatographic separation but only by applying and developing the MS/MS features.
Assuntos
Anidrases Carbônicas , Espectrometria de Massas em Tandem , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Algoritmos , Inibidores da Anidrase Carbônica , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodosRESUMO
Some 2,4-disubstituted quinazolines were synthesized and studied as multidrug resistance (MDR) reversers. The new derivatives carried the quinazoline-4-amine scaffold found in modulators of the ABC transporters involved in MDR, as the TKIs gefitinib and erlotinib. Their behaviour on the three ABC transporters, P-gp, MRP1 and BCRP, was investigated. Almost all compounds inhibited the P-gp activity in MDCK-MDR1 cells overexpressing P-gp, showing EC50 values in the nanomolar range (1 d, 1 e, 2 a, 2 c, 2 e). Some compounds were active also towards MRP1 and/or BCRP. Docking results obtained by in silico studies on the P-gp crystal structure highlighted common features for the most potent compounds. The P-gp selective compound 1 e was able to increase the doxorubicin uptake in HT29/DX cells and to restore its antineoplastic activity in resistant cancer cells in the same extent of sensitive cells. Compound 2 a displayed a dual inhibitory effect showing good activities towards both P-gp and BCRP.
Assuntos
Antineoplásicos , Quinazolinas , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP , Antineoplásicos/química , Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Proteínas de Neoplasias/metabolismo , Quinazolinas/farmacologiaRESUMO
A series of histamine (HST)-related compounds were synthesized and tested for their activating properties on five physiologically relevant human Carbonic Anhydrase (hCA) isoforms (I, II, Va, VII and XIII). The imidazole ring of HST was replaced with different 5-membered heterocycles and the length of the aliphatic chain was varied. For the most interesting compounds some modifications on the terminal amino group were also performed. The most sensitive isoform to activation was hCA I (KA values in the low micromolar range), but surprisingly none of the new compounds displayed activity on hCA II. Some derivatives (1, 3a and 22) displayed an interesting selectivity for activating hCA I over hCA II, Va, VII and XIII.
Assuntos
Anidrase Carbônica I/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Histamina/química , Histamina/farmacologia , Anidrase Carbônica I/efeitos dos fármacos , Anidrase Carbônica II/efeitos dos fármacos , Anidrase Carbônica II/metabolismo , Anidrase Carbônica V/efeitos dos fármacos , Anidrase Carbônica V/metabolismo , Anidrases Carbônicas/efeitos dos fármacos , Anidrases Carbônicas/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Histamina/análogos & derivados , Histamina/síntese química , Humanos , Imidazóis/química , Isoformas de Proteínas/efeitos dos fármacos , Isoformas de Proteínas/metabolismoRESUMO
Targeting Carbonic Anhydrases (CAs) represents a strategy to treat several diseases, from glaucoma to cancer. To widen the structure-activity relationships (SARs) of our series of piperazines endowed with potent human carbonic anhydrase (hCA) inhibition, a new series of chiral piperazines carrying a (2-hydroxyethyl) group was prepared. The Zn-binding function, the 4-sulfamoylbenzoyl moiety, was connected to one piperazine N-atom, while the other nitrogen was decorated with alkyl substituents. In analogy to the approach used for the synthesis of the previously reported series, the preparation of the new compounds started with (R)- and (S)-aspartic acid. A partial racemization occurred during the synthesis. In order to overcome this problem, other chemical strategies were investigated. The inhibitory activity of the new polar derivatives against four hCAs isoforms I, II, IV and IX using a stopped flow CO2 hydrase assay was determined. Some compounds showed potency in the nanomolar range and a preference for inhibiting hCA IX.
Assuntos
Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Glaucoma/tratamento farmacológico , Simulação de Dinâmica Molecular , Soluções Oftálmicas/farmacologia , Piperazina/farmacologia , Animais , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glaucoma/metabolismo , Glaucoma/patologia , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Masculino , Estrutura Molecular , Soluções Oftálmicas/síntese química , Soluções Oftálmicas/química , Piperazina/síntese química , Piperazina/química , Coelhos , Relação Estrutura-AtividadeRESUMO
BACKGROUND: MDR in bacteria is threatening to public health. Overexpression of efflux pumps is an important cause of MDR. The co-administration of antimicrobial drugs and efflux pump inhibitors (EPIs) is a promising approach to address the problem of MDR. OBJECTIVES: To identify new putative EPIs and to characterize their mechanisms of action. METHODS: The effects of four selected piperazine derivatives on resistance-nodulation-cell division (RND) pumps was evaluated in Escherichia coli strains overexpressing or not expressing RND pumps by assays aimed at evaluating antibiotic potentiation, membrane functionality, ethidium bromide accumulation and AcrB expression. The cytotoxicity of selected piperazines towards primary cultures of human dermal fibroblasts was also investigated. RESULTS: Four molecules enhanced levofloxacin activity against strains overexpressing RND efflux pumps (AcrAB-TolC and AcrEF-TolC), but not against RND pump-deficient strains. They had little effects on membrane potential. Molecule 4 decreased, whereas the other three increased, membrane permeability compared with untreated control cells. The four molecules showed differences in the specificity of interaction with RND efflux pumps, by inactivating the transport of one or more antibiotics, and in the levels of ethidium bromide accumulation and of acrB expression inhibition. CONCLUSIONS: Piperazine derivatives are good candidates as inhibitors of RND efflux pumps. They decreased the activity of RND pumps by mixed mechanisms of action. Small structural differences among the molecules can be critical in defining their behaviour.
Assuntos
Antibacterianos , Proteínas de Escherichia coli , Escherichia coli , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Piperazinas , Antibacterianos/farmacologia , Divisão Celular , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Piperazinas/farmacologiaRESUMO
Differently substituted ß-hydroxy- and ß-amino dialkyl and alkyl-aryl tellurides and selenides have been prepared through ring-opening reactions of epoxides and aziridines with selenium- or tellurium-centered nucleophiles. The antioxidant properties and the cytotoxicity of such compounds have been investigated on normal human dermal fibroblasts. Most of the studied compounds exhibited a low cytotoxicity and a number of them proved to be non-toxic, not showing any effect on cell viability even at the highest concentration used (100 µM). The obtained results showed a significant antioxidant potential of the selected organotellurium compounds, particularly evident under conditions of exogenously induced oxidative stress. The antioxidant activity of selenium-containing analogues of active tellurides has also been evaluated on cells, highlighting that the replacement of Se with Te brought about a significant increase in the peroxidase activity.
Assuntos
Antioxidantes/farmacologia , Calcogênios/farmacologia , Ditiotreitol/metabolismo , Antioxidantes/síntese química , Antioxidantes/química , Células Cultivadas , Calcogênios/síntese química , Calcogênios/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Aim: To investigate the action mechanism of 1-benzyl-1,4-diazepane (1-BD) as efflux pump inhibitor (EPI) in Escherichia coli mutants: ΔacrAB or overexpressing AcrAB and AcrEF efflux pumps. Materials & methods: Effect of 1-BD on: antibiotic potentiation, by microdilution method; membrane functionality, by fluorimetric assays; ethidium bromide accumulation, by fluorometric real-time efflux assay; AcrB expression, by quantitative photoactivated localization microscopy. Results: 1-BD decreases the minimal inhibitory concentration of levofloxacin and other antibiotics and increase ethidium bromide accumulation in E. coli overexpressing efflux pumps but not in the ΔacrAB strain. 1-BD increases membranes permeability, without sensibly affecting inner membrane polarity and decreases acrAB transcription. Conclusion: 1-BD acts as an EPI in E. coli with a mixed mechanism, different from that of major reference EPIs.
Assuntos
Antibacterianos/farmacologia , Azepinas/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Farmacorresistência Bacteriana Múltipla , Escherichia coli/genética , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Levofloxacino/farmacologia , Lipoproteínas/genética , Lipoproteínas/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Testes de Sensibilidade Microbiana , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismoRESUMO
Although agonists and antagonists of muscarinic receptors have been known for long time, there is renewed interest in compounds (such as allosteric or bitopic ligands, or biased agonists) able to differently and selectively modulate these receptors. As a continuation of our previous research, we designed a new series of dimers of the well-known cholinergic agonist carbachol. The new compounds were tested on the five cloned human muscarinic receptors (hM1-5) expressed in CHO cells by means of equilibrium binding experiments, showing a dependence of the binding affinity on the length and position of the linker connecting the two monomers. Kinetic binding studies revealed that some of the tested compounds were able to slow the rate of NMS dissociation, suggesting allosteric behavior, also supported by docking simulations. Assessment of ERK1/2 phosphorylation on hM1, hM2 and hM3 activation showed that the new compounds are endowed with muscarinic antagonist properties. At hM2 receptors, some compounds were able to stimulate GTPγS binding but not cAMP accumulation, suggesting a biased behavior. Classification, Molecular and cellular pharmacology.
Assuntos
Carbacol/farmacologia , Agonistas Muscarínicos/farmacologia , Antagonistas Muscarínicos/farmacologia , Receptores Muscarínicos/efeitos dos fármacos , Animais , Células CHO , Carbacol/química , Carbacol/metabolismo , Cricetulus , AMP Cíclico/metabolismo , Dimerização , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Humanos , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Agonistas Muscarínicos/química , Agonistas Muscarínicos/metabolismo , Antagonistas Muscarínicos/química , Antagonistas Muscarínicos/metabolismo , Fosforilação , Ligação Proteica , Receptores Muscarínicos/genética , Receptores Muscarínicos/metabolismo , Transdução de Sinais , Relação Estrutura-AtividadeRESUMO
The Carbonic Anhydrase (CA, EC 4.2.1.1) activating properties of histamine have been known for a long time. This compound has been extensively modified but only in few instances the imidazole ring has been replaced with other heterocycles. It was envisaged that the imidazoline ring could be a bioisoster of the imidazole moiety. Indeed, we report that clonidine, a 2-aminoimidazoline derivative, was found able to activate several human CA isoforms (hCA I, IV, VA, VII, IX, XII and XIII), with potency in the micromolar range, while it was inactive on hCA II. A series of 2-aminoimidazoline, structurally related to clonidine, was then synthesised and tested on selected hCA isoforms. The compounds were inactive on hCA II while displayed activating properties on hCA I, VA, VII and XIII, with KA values in the micromolar range. Two compounds (10 and 11) showed some preference for the hCA VA or VII isoforms.
Assuntos
Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Clonidina/farmacologia , Imidazóis/farmacologia , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Clonidina/química , Relação Dose-Resposta a Droga , Humanos , Imidazóis/síntese química , Imidazóis/química , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Aiming to deepen the structure-activity relationships of the two P-glycoprotein (P-gp) modulators elacridar and tariquidar, a new series of amide and ester derivatives carrying a 6,7-dimethoxy-2-phenethyl-1,2,3,4-tetrahydroisoquinoline scaffold linked to different methoxy-substituted aryl moieties were synthesised. The obtained compounds were evaluated for their P-gp interaction profile and selectivity towards the two other ABC transporters, multidrug-resistance-associated protein-1 and breast cancer resistance protein, showing to be very active and selective versus P-gp. Two amide derivatives, displaying the best P-gp activity, were tested in co-administration with the antineoplastic drug doxorubicin in different cancer cell lines, showing a significant sensitising activity towards doxorubicin. The investigation on the chemical stability of the derivatives towards spontaneous or enzymatic hydrolysis, showed that amides are stable in both models while some ester compounds were hydrolysed in human plasma. This study allowed us to identify two chemosensitizers that behave as non-transported substrates and are characterised by different selectivity profiles.
Assuntos
Amidas/farmacologia , Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ésteres/farmacologia , Neoplasias/tratamento farmacológico , Tetra-Hidroisoquinolinas/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Amidas/síntese química , Amidas/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Células Cultivadas , Cães , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Ésteres/síntese química , Ésteres/química , Humanos , Estrutura Molecular , Neoplasias/metabolismo , Relação Estrutura-Atividade , Tetra-Hidroisoquinolinas/síntese química , Tetra-Hidroisoquinolinas/químicaRESUMO
A new series of N,N-bis(alkanol)amine aryl diesters was synthesized and studied as dual P-glycoprotein (P-gp) and carbonic anhydrase XII inhibitors (CA XII). These hybrids should be able to synergistically overcome P-gp mediated multidrug resistance (MDR) in cancer cells. It was reported that the efflux activity of P-gp could be modulated by CA XII, as the pH reduction caused by CA XII inhibition produces a significant decrease in P-gp ATPase activity. The new compounds reported here feature both P-gp and CA XII binding moieties. These hybrids contain a N,N-bis(alkanol)amine diester scaffold found in P-glycoprotein ligands and a coumarin or benzene sulfonamide moiety to target CA XII. Many compounds displayed a dual activity against P-gp and CA XII being active in the Rhd 123 uptake test on K562/DOX cells and in the hCA XII inhibition test. On LoVo/DOX cells, that overexpress both P-gp and CA XII, some coumarin derivatives showed a high MDR reversal effect in Rhd 123 uptake and doxorubicin cytotoxicity enhancement tests. In particular, compounds 7 and 8 showed higher activity than verapamil and were more potent on LoVo/DOX than on K562/DOX cells overexpressing only P-gp. They can be considered as valuable candidates for selective P-gp/CA XII inhibition in MDR cancer cells.