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1.
Life Sci ; 239: 116884, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31689440

RESUMO

C57BL6/J (B6) mice lacking Se-dependent GSH peroxidase 1 and 2 (GPx1/2-DKO) develop mild to moderate ileocolitis around weaning. These DKO mice have a disease resembling human very-early-onset inflammatory bowel disease (VEOIBD), which is associated with mutations in NADPH oxidase genes. Drugs including dexamethasone (Dex), Tofacitinib (Tofa; a Janus kinase/JAK inhibitor) and anti-TNF antibody are effective to treat adult, but not pediatric IBD. AIMS: To test the efficacy of hydrophobic Dex and hydrophilic Dex phosphate (Dex phos), Tofa, anti-Tnf Ab, Noxa1ds-TAT and gp91ds-TAT peptides (inhibiting NOX1 and NOX2 assembly respectively), antioxidant MJ33 and ML090, and pifithrin-α (p53 inhibitor) on alleviation of gut inflammation in DKO weanlings. MAIN METHODS: All treatments began on 22-day-old GPx1/2-DKO mice. The mouse intestine pathology was compared between the drug- and vehicle-treated groups after six or thirteen days of treatment. KEY FINDINGS: Among all drugs tested, Dex, Dex phos and Tofa were the strongest to suppress ileocolitis in the DKO weanlings. Dex, Dex phos and Tofa inhibited crypt apoptosis and increased crypt density. Dex or Dex phos alone also inhibited cell proliferation, exfoliation and crypt abscess in the ileum. Dex, but not Tofa, retarded mouse growth. Both Dex and Tofa inhibited ileum Nox1, Nox4 and Duox2, but not Nox2 gene expression. Noxa1ds-TAT and gp91ds-TAT peptides as well as MJ33 had subtle effect on suppressing pathology, while others had negligible effect. SIGNIFICANCE: These findings suggest that NADPH oxidases can be novel drug targets for pediatric IBD therapy, and Tofa may be considered for treating VEOIBD.


Assuntos
Doença de Crohn/tratamento farmacológico , Dexametasona/farmacologia , Piperidinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Animais , Apoptose/genética , Doença de Crohn/metabolismo , Dexametasona/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glutationa Peroxidase/fisiologia , Íleo/patologia , Inflamação/patologia , Doenças Inflamatórias Intestinais/genética , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidase 1 , NADPH Oxidases/efeitos dos fármacos , NADPH Oxidases/metabolismo , Oxirredução , Peroxidases , Piperidinas/metabolismo , Pirimidinas/metabolismo , Pirróis/metabolismo
2.
Life Sci ; 239: 117045, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730866

RESUMO

AIMS: Chronic inflammation is associated with the production of high levels of proinflammatory cytokines via the JAK-STAT and NF-κB signalling pathways which are known to be inhibited by tofacitinib and aspirin respectively. High levels of these cytokines increase the synthesis of suppressors of cytokines (SOCS), which at high levels inhibit insulin signalling leading to insulin resistance. The effects of tofacitinib and aspirin on the degree of insulin resistance in type 2 diabetic rats were determined. MATERIALS AND METHODS: Rats were induced with type 2 diabetes (T2D) by administration of 10% fructose solution (ad libitum) followed by streptozotocin injection (40 mg/kg BW) and treated with different doses of tofacitinib (10 and 20 mg/kg BW), aspirin (100 and 200 mg/kg BW) and combination of the two drugs at both doses for 9 weeks. KEY FINDINGS: Results showed that separate treatment with 10 mg/kg BW tofacitinib and 100 mg/kg BW aspirin significantly (P < 0.05) decreased tumour necrosis factor-α (TNF-α), interleukin 6 (IL-6) and serum amyloid A when compared to diabetic untreated rats. However, the combined therapy (10 mg/kg BW tofacitinib and 100 mg/kg BW aspirin) significantly decreased the levels of TNF-α, IL-6, serum amyloid A, HOMA-IR, blood glucose level and SOC-3 gene expression but significantly (P < 0.05) improved glucose homoestasis, insulin secretion, HOMA-ß and GLUT-4 gene expression when compared to diabetic untreated rat. CONCLUSION: It was concluded that simultaneous inhibition of the JAK-STAT and NF-κB signalling pathways with tofacitinib and aspirin respectively, could mitigate insulin resistance and hyperglycemia in T2D.


Assuntos
Aspirina/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Piperidinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Animais , Aspirina/metabolismo , Glicemia/efeitos dos fármacos , Citocinas , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Feminino , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Resistência à Insulina/fisiologia , Interleucina-6/metabolismo , Janus Quinases/metabolismo , Masculino , NF-kappa B/metabolismo , Piperidinas/metabolismo , Pirimidinas/metabolismo , Pirróis/metabolismo , Ratos , Ratos Wistar , Fatores de Transcrição STAT/metabolismo , Proteína Amiloide A Sérica/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
4.
J Mass Spectrom ; 54(9): 738-749, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31368246

RESUMO

Black pepper, though commonly employed as a spice, has many medicinal properties. It consists of volatile oils, alkaloids, pungent resins, etc., of which piperine is a major constituent. Though safe at low doses, piperine causes alteration in the activity of drug metabolising enzymes and transporters at high dose and is known to precipitate liver toxicity. It has a potential to form reactive metabolite(s) (RM) owing to the presence of structural alerts, such as methylenedioxyphenyl (MDP), α, ß-unsaturated carbonyl group (Michael acceptor), and piperidine. The present study was designed to detect and characterize stable and RM(s) of piperine formed on in vitro incubation with human liver microsomes. The investigation of RMs was done with the aid of trapping agents, viz, glutathione (GSH) and N-acetylcysteine (NAC). The samples were analysed by ultra-high performance liquid chromatography coupled with high resolution mass spectrometry (UHPLC-HRMS) using Thermo Scientific Q Exactive Plus Orbitrap. Full scan MS followed by data-dependent MS2 (Full MS-ddMS2 ) mode was used to establish mass spectrometric fragmentation pathways of protonated piperine and its metabolites. In total, four stable metabolites and their isomers (M1a-c, M2a-b, M3a-c, and M4a-b) were detected. Their formation involved removal of carbon (3, M1a-c), hydroxylation (2, M2a-b), hydroxylation with hydrogenation (3, M3a-c), and dehydrogenation (2, M4a-b). Out of these metabolites, M1, M2, and M3 are reported earlier in the literature, but their isomers and two M4 variants are novel. In addition, six novel conjugates of RMs, including three GSH conjugates of m/z 579 and three NAC conjugates of m/z 435, were also observed.


Assuntos
Alcaloides/análise , Alcaloides/metabolismo , Benzodioxóis/análise , Benzodioxóis/metabolismo , Microssomos Hepáticos/metabolismo , Piperidinas/análise , Piperidinas/metabolismo , Alcamidas Poli-Insaturadas/análise , Alcamidas Poli-Insaturadas/metabolismo , Acetilcisteína/química , Cromatografia Líquida de Alta Pressão , Glutationa/química , Humanos , Isomerismo , Espectrometria de Massas em Tandem
5.
Elife ; 82019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31343405

RESUMO

ATP-sensitive potassium (KATP) channels composed of a pore-forming Kir6.2 potassium channel and a regulatory ABC transporter sulfonylurea receptor 1 (SUR1) regulate insulin secretion in pancreatic ß-cells to maintain glucose homeostasis. Mutations that impair channel folding or assembly prevent cell surface expression and cause congenital hyperinsulinism. Structurally diverse KATP inhibitors are known to act as pharmacochaperones to correct mutant channel expression, but the mechanism is unknown. Here, we compare cryoEM structures of a mammalian KATP channel bound to pharmacochaperones glibenclamide, repaglinide, and carbamazepine. We found all three drugs bind within a common pocket in SUR1. Further, we found the N-terminus of Kir6.2 inserted within the central cavity of the SUR1 ABC core, adjacent the drug binding pocket. The findings reveal a common mechanism by which diverse compounds stabilize the Kir6.2 N-terminus within SUR1's ABC core, allowing it to act as a firm 'handle' for the assembly of metastable mutant SUR1-Kir6.2 complexes.


Assuntos
Microscopia Crioeletrônica , Canais KATP/metabolismo , Canais KATP/ultraestrutura , Mamíferos/metabolismo , Preparações Farmacêuticas/metabolismo , Animais , Sítios de Ligação , Carbamatos/química , Carbamatos/metabolismo , Linhagem Celular , Cricetinae , Cisteína/genética , Glibureto/química , Glibureto/metabolismo , Humanos , Canais KATP/química , Modelos Moleculares , Mutação/genética , Preparações Farmacêuticas/química , Piperidinas/química , Piperidinas/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/química , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Ligação Proteica , Ratos
6.
Biomed Chromatogr ; 33(11): e4645, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31306503

RESUMO

AdipoRon is an orally active adiponectin receptor agonist. The aim of this study was to characterize the metabolites of AdipoRon in rat and human liver microsomes using ultra-high performance liquid chromatography combined with Q-Exactive Orbitrap tandem mass spectrometry (UPLC-Q-Exactive-Orbitrap-MS) together with data processing techniques including extracted ion chromatograms and a mass defect filter. AdipoRon (10 µm) was incubated with liver microsomes in the presence of NADPH and this resulted in a total of 11 metabolites being detected. The identities of these metabolites were characterized by comparing their accurate masses and fragment ions as well as their retention times with those of AdipoRon using MetWorks software. Metabolites M1-M3, M6, and M8-M11 were identified for the first time. Metabolite M4, the major metabolite both in rat and human liver microsomes, was further confirmed using the reference standard. Our results revealed that the metabolic pathways of AdipoRon in liver microsomes were N-dealkylation (M2), hydroxylation (M, M5-M9), carbonyl reduction (M4) and the formation of amide (M10 and M11). Our results provide valuable information about the in vitro metabolism of AdipoRon, which would be helpful for us to understand the mechanism of the elimination of AdipoRon and, in turn, its effectiveness and toxicity.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Microssomos Hepáticos/metabolismo , Piperidinas/química , Piperidinas/metabolismo , Espectrometria de Massas em Tandem/métodos , Animais , Humanos , Piperidinas/análise , Piperidinas/farmacocinética , Ratos
7.
Int J Mol Sci ; 20(12)2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31212743

RESUMO

The bioactive piperine (1-piperoyl piperidine) compound found in some pepper species (Piper nigrum linn and Piper sarmentosum Roxb) has been shown to have therapeutic properties and to be useful for well-being. The tests used to validate these properties were performed in vitro or with small rats. However, in all these assays, the molecular approach was absent. Although the first therapeutic trials relied on the use of rats, no proposal was mentioned either experimentally or computationally at the molecular level regarding the interaction between piperine and rat serum albumin (RSA). In the present study, several spectroscopic techniques were employed to characterize rat serum albumin and, aided by computational techniques, the protein modeling was proposed. From the spectroscopic results, it was possible to estimate the binding constant (3.9 × 104 M-1 at 288 K) using the Stern-Volmer model and the number of ligands (three) associated with the protein applying interaction density function model. The Gibbs free energy, an important thermodynamic parameter, was determined (-25 kJ/mol), indicating that the interaction was spontaneous. This important set of experimental results served to parameterize the computational simulations. The results of molecular docking and molecular dynamics matched appropriately made it possible to have detailed microenvironments of RSA accessed by piperine.


Assuntos
Alcaloides/química , Benzodioxóis/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Piperidinas/química , Alcamidas Poli-Insaturadas/química , Albumina Sérica/química , Algoritmos , Alcaloides/metabolismo , Animais , Benzodioxóis/metabolismo , Sítios de Ligação , Dicroísmo Circular , Ligações de Hidrogênio , Conformação Molecular , Estrutura Molecular , Piperidinas/metabolismo , Alcamidas Poli-Insaturadas/metabolismo , Ligação Proteica , Ratos , Albumina Sérica/metabolismo , Espectrometria de Fluorescência , Termodinâmica
8.
Antonie Van Leeuwenhoek ; 112(10): 1425-1445, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31111331

RESUMO

This study set out to isolate and identify epiphytic yeasts producing pulcherrimin, and to evaluate their potential as biological control agents (BCAs). We isolated Metschnikowia sp. strains from flowers and fruits collected in Poland. The plant material had been collected between April to September 2017 from two small orchards where traditional organic management is employed. We identified the essential phenotypic features of the yeast, including assimilation and enzymatic profiles, stress resistance, adhesion properties, and antimicrobial activity against various fungi involved in crop and/or food spoilage. Yeast screening was performed using YPD agar supplemented with chloramphenicol and Fe(III) ions. Taxonomic classification was determined by sequence analysis of the D1/D2 domains of the large subunit rRNA gene. The isolates were identified as Metschnikowia andauensis and Metschnikowia sinensis. The yeast isolates were further characterized based on their enzymatic and assimilation profiles, as well as their growth under various stress conditions. In addition, the hydrophobicity and adhesive abilities of the Metschnikowia isolates were determined using a MATH test and luminometry. Their antagonistic action against molds representing typical crop spoiling microflora was also evaluated. The assimilation profiles of the wild isolates were similar to those displayed by collection strains of M. pulcherrima. However, some of the isolates displayed more beneficial phenotypic properties, especially good growth under stress conditions. Several of the epiphytes grew well over a wider range of temperatures (8-30 °C) and pH levels (3-9), and additionally showed elevated tolerance to ethanol (8%), glucose (30%), and peroxides (50 mM). The hydrophobicity and adhesion of the yeast cells were strain- and surface-dependent. The tested yeasts showed potential for use as BCAs, with some exhibiting strong antagonism against molds belonging to the genera Alternaria, Botrytis, Fusarium, Rhizopus, and Verticillium, as well as against yeasts isolated as food spoilage microbiota.


Assuntos
Aminoácidos Sulfúricos/metabolismo , Fungos/efeitos dos fármacos , Metschnikowia/classificação , Metschnikowia/isolamento & purificação , Controle Biológico de Vetores , Piperidinas/metabolismo , Antibiose , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Flores/microbiologia , Frutas/microbiologia , Fungos/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Metschnikowia/genética , Metschnikowia/fisiologia , Técnicas de Tipagem Micológica , Filogenia , Polônia , RNA Ribossômico/genética , Análise de Sequência de DNA , Temperatura Ambiente
9.
Drug Des Devel Ther ; 13: 925-940, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30962675

RESUMO

Background: Association of long hydrocarbon chain with alginate molecule imparts surface active properties and increases chain flexibility. Purpose: This work studied the efficacy of synthesized hexyl alginate derivative as a film-forming material with unique amphiphilic and mechanical properties for the preparation of rapidly disintegrating repaglinide oral films with higher drug release rate and improved bioavailability. Methods: Alginate hexyl amide derivative was prepared and used in the formulation of oral films by solvent casting technique. Using Box-Behnken experimental design, formulations were optimized at different polymer, plasticizer, and disintegrant levels as independent variables for maximum drug release rate, higher tensile strength, and shortest disintegration time as responses. Optimized film formulae were fully evaluated and subjected to further in vivo bioavailability studies in rabbits. Results: Higher dependency of response results on the selected variables was observed. Optimized formula showed satisfactory tensile strength (145.862 g/cm2), rapid disintegration (22.2 seconds), and higher drug release rate (97.799% within 30 minutes). The drug bioavailability was significantly improved in comparison with plain drug and conventional alginate oral films, where the AUC and Cmax values reached 296.072 µg.h/mL and 116.932 µg/mL in comparison with 164.917 µg.h/mL and 56.568 µg/mL for alginate film and 95.368 µg.h/mL and 31.925 µg/mL for plain drug, respectively. Tmax also showed significant reduction to be only 30 minutes in comparison with 60 minutes for other forms. Conclusion: This led to the final conclusion that the synthesized alginate derivative is an innovative promising film-forming material with unique mechanical and drug release properties for application in buccal drug delivery especially of Biopharmaceutics Classification System (BCS) class II drugs to increase solubility and improve bioavailability.


Assuntos
Alginatos/química , Carbamatos/metabolismo , Piperidinas/metabolismo , Tensoativos/química , Administração Oral , Alginatos/administração & dosagem , Alginatos/metabolismo , Disponibilidade Biológica , Carbamatos/administração & dosagem , Carbamatos/química , Liberação Controlada de Fármacos , Piperidinas/administração & dosagem , Piperidinas/química , Tensoativos/administração & dosagem , Tensoativos/metabolismo , Resistência à Tração
10.
Bioorg Med Chem ; 27(10): 1990-1996, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30975500

RESUMO

Sigma-1 receptor imaging probes for determining the expression levels are desirable for diagnoses of various diseases and companion diagnoses of therapeutic agents targeting the sigma-1 receptor. In this study, we aimed to develop probes with higher affinity for the sigma-1 receptor. For this purpose, we synthesized and evaluated compounds, namely, vesamicol derivatives, in which alkyl chains of varying chain length were introduced between a piperazine ring and a benzene ring. The binding affinity of the vesamicol derivatives for the sigma-1 receptor tended to increase depending on the length of the alkyl chain between the benzene ring and the piperazine ring. The sigma-1 receptor of 2-(4-(3-phenylpropyl)piperazin-1-yl)cyclohexan-1-ol (5) (Ki = 5.8 nM) exhibited the highest binding affinity; therefore, we introduced radioiodine into the benzene ring in 5. The radioiodine labeled probe [125I]2-(4-(3-(4-iodophenyl)propyl)piperazin-1-yl)cyclohexan-1-ol ([125I]10) showed high accumulation in the sigma-1 receptor expressing DU-145 cells both in vitro and in vivo. Co-injection of [125I]10 with an excess level of a sigma receptor ligand, haloperidol, resulted in a significant decrease in the tumor accumulation in vitro and in vivo, indicating sigma receptor-mediated tumor uptake. These results provide useful information for developing sigma-1 receptor imaging probes.


Assuntos
Compostos Aza/química , Piperidinas/química , Compostos Radiofarmacêuticos/síntese química , Receptores sigma/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Radioisótopos do Iodo/química , Marcação por Isótopo , Masculino , Camundongos , Camundongos Nus , Neoplasias/diagnóstico por imagem , Piperidinas/síntese química , Piperidinas/metabolismo , Ligação Proteica , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/metabolismo , Receptores sigma/química , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único , Transplante Heterólogo
11.
Bioorg Med Chem ; 27(10): 2019-2026, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30975505

RESUMO

Neurokinin-3 receptor (NK3R) plays a pivotal role in the release of gonadotropin-releasing hormone in the hypothalamus-pituitary-gonadal (HPG) axis. To develop novel NK3R antagonists with less environmental toxicity, a series of heterocyclic scaffolds for the triazolopiperazine substructure in an NK3R antagonist fezolinetant were designed and synthesized. An isoxazolo[3,4-c]piperidine derivative exhibited moderate NK3R antagonistic activity and favorable properties that were decomposable under environmental conditions.


Assuntos
Piperidinas/química , Receptores da Neurocinina-3/antagonistas & inibidores , Cristalografia por Raios X , Compostos Heterocíclicos com 2 Anéis/síntese química , Compostos Heterocíclicos com 2 Anéis/química , Concentração Inibidora 50 , Conformação Molecular , Fotólise , Piperidinas/metabolismo , Receptores da Neurocinina-3/metabolismo , Relação Estrutura-Atividade , Luz Solar , Tiadiazóis/síntese química , Tiadiazóis/química
12.
mBio ; 10(1)2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755505

RESUMO

The large genome of human cytomegalovirus (HCMV) is transcribed by RNA polymerase II (Pol II). However, it is not known how closely this betaherpesvirus follows host transcriptional paradigms. We applied PRO-Seq and PRO-Cap methods to profile and quantify transcription initiation and productive elongation across the host and virus genomes in late infection. A major similarity between host transcription and viral transcription is that treatment of cells with the P-TEFb inhibitor flavopiridol preempts virtually all productive elongation, which otherwise covers most of the HCMV genome. The deep, nucleotide resolution identification of transcription start sites (TSSs) enabled an extensive analysis of core promoter elements. An important difference between host and viral transcription is that initiation is much more pervasive on the HCMV genome. The sequence preferences in the initiator region around the TSS and the utilization of upstream T/A-rich elements are different. Upstream TATA positions the TSS and boosts initiation in both the host and the virus, but upstream TATT has a significant stimulatory impact only on the viral template. The major immediate early (MIE) promoter remained active during late infection and was accompanied by transcription of both strands of the MIE enhancer from promoters within the enhancer. Surprisingly, we found that the long noncoding RNA4.9 is intimately associated with the viral origin of replication (oriLyt) and was transcribed to a higher level than any other viral or host promoter. Finally, our results significantly contribute to the idea that late in infection, transcription takes place on viral genomes that are not highly chromatinized.IMPORTANCE Human cytomegalovirus infects more than half of humans, persists silently in virtually all tissues, and produces life-threatening disease in immunocompromised individuals. HCMV is also the most common infectious cause of birth defects and the leading nongenetic cause of sensorineural hearing loss in the United States. Because there is no vaccine and current drugs have problems with potency, toxicity, and antiviral drug resistance, alternative treatment strategies that target different points of viral control are needed. Our current study contributes to this goal by applying newly developed methods to examine transcription of the HCMV and host genomes at nucleotide resolution in an attempt to find targetable differences between the two. After a thorough analysis of productive elongation and of core promoter element usage, we found that some mechanisms of regulating transcription are shared between the host and HCMV but that others are distinctly different. This suggests that HCMV transcription may be a legitimate target for future antiviral therapies and this might translate to other herpesviruses.


Assuntos
Citomegalovirus/genética , Genoma Humano , Genoma Viral , Regiões Promotoras Genéticas , RNA Polimerase II/metabolismo , Sítio de Iniciação de Transcrição , Iniciação da Transcrição Genética , Células Cultivadas , Inibidores Enzimáticos/metabolismo , Flavonoides/metabolismo , Humanos , Piperidinas/metabolismo
13.
Curr Drug Metab ; 20(4): 266-274, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30636597

RESUMO

OBJECTIVE: The purpose of this systematic review and meta-analysis was to summarize the potential impact of CYP2C8 and SLCO1B1 genetic polymorphisms on repaglinide pharmacokinetics. METHODS: A systematic search was conducted using electronic databases. Eligible studies reported data from pharmacokinetic evaluations of repaglinide in healthy adults according to different categories of CYP2C8 and SLCO1B1 genetic polymorphisms. RESULTS: Six studies including a total of 191 participants met the inclusion criteria. We noted that CYP2C8 *1/*3 carriers exhibited lower AUC(0-∞) (SMD: -0.77; 95%CI: -1.23 to -0.30; P=0.001) and Cmax (SMD: -0.94; 95%CI: - 1.41 to -0.47; P<0.001) than CYP2C8 *1/*1 carriers. There were no significant differences in AUC(0-∞), Cmax, t1/2 and mean change in blood glucose concentration between *1/*4 and *1/*1 carriers. Further, *3/*3 carriers had lower Cmax (SMD: -1.42; 95%CI: -2.66 to -0.17; P=0.026) than *1/*1 carriers. Additionally, *3/*3 carriers had lower Cmax than *1/*3 carriers (SMD: -1.20; 95%CI: -2.40 to -0.00; P=0.050). Finally, we noted that repaglinide pharmacokinetics did not differ by SLCO1B1 genotype. CONCLUSION: The current systematic review and meta-analysis indicated that the genotype of CYP2C8, but not SLCO1B1, may affect repaglinide pharmacokinetics. However, because of the comparatively insufficient number of published studies included, our conclusions require support from additional studies.


Assuntos
Carbamatos/farmacocinética , Citocromo P-450 CYP2C8/genética , Hipoglicemiantes/farmacocinética , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Piperidinas/farmacocinética , Polimorfismo Genético , Carbamatos/metabolismo , Citocromo P-450 CYP2C8/metabolismo , Hipoglicemiantes/metabolismo , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Piperidinas/metabolismo
14.
Xenobiotica ; 49(2): 187-199, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29448869

RESUMO

1. The objective of our study was to develop and validate a cocktail approach to allow the simultaneous characterization of various CYP450-mediated oxidations by human heart microsomes for nine probe drug substrates, namely, 7-ethoxyresorufin, bupropion, repaglinide, tolbutamide, bufuralol, chlorzoxazone, ebastine, midazolam and dodecanoic acid. 2. The first validation step was conducted using recombinant human CYP450 isoenzymes by comparing activity measured for each probe drug as a function of (1) buffer used, (2) selectivity towards specific isoenzymes and (3) drug interactions between probes. Activity was all measured by validated LC-MSMS methods. 3. Two cocktails were then constituted with seven of the nine drugs and subjected to kinetic validation. Finally, all probe drugs were incubated with human heart microsomes prepared from ventricular tissues obtained from 12 patients undergoing cardiac transplantation. 4. Validated cocktail #1 including bupropion, chlorzoxazone, ebastine and midazolam was used to characterize CYP2B6-, 2E1-, 2J2- and 3A5-mediated metabolism in human hearts. 5. Cocktail #2 which includes bufuralol, 7-ethoxyresorufin and repaglinide failed the validation step. Substrates in cocktail #2 as well as tolbutamide and dodecanoic acid had to be incubated separately because of their physico-chemical characteristics (solubility and ionization) or drug interactions. 6. Activity in HHM was the highest towards ebastine, chlorzoxazone and tolbutamide.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Microssomos/metabolismo , Bupropiona/metabolismo , Butirofenonas/metabolismo , Carbamatos/metabolismo , Clorzoxazona/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Etanolaminas/metabolismo , Humanos , Ácidos Láuricos/metabolismo , Midazolam/metabolismo , Miocárdio/metabolismo , Oxazinas/metabolismo , Piperidinas/metabolismo , Tolbutamida/metabolismo
15.
J Nucl Med ; 60(1): 129-134, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30213846

RESUMO

Accumulation of hyperphosphorylated tau, a microtubule-associated protein, plays an important role in the progression of Alzheimer disease. Animal studies suggest that one strategy for treating Alzheimer disease and related tauopathies may be inhibition of O-GlcNAcase (OGA), which may subsequently decrease pathologic tau phosphorylation. Here, we report the pharmacokinetics of a novel PET radioligand, 18F-LSN3316612, which binds with high affinity and selectivity to OGA. Methods: PET imaging was performed on rhesus monkeys at baseline and after administration of either thiamet-G, a potent OGA inhibitor, or nonradioactive LSN3316612. The density of the enzyme was calculated as distribution volume using a 2-tissue-compartment model and serial concentrations of parent radioligand in arterial plasma. The radiation burden for future studies was based on whole-body imaging of monkeys. Oga ∆Br, a mouse brain-specific knockout of Oga, was also scanned to assess the specificity of the radioligand for its target enzyme. Results: Uptake of radioactivity in monkey brain was high (∼5 SUV) and followed by slow washout. The highest uptake was in the amygdala, followed by striatum and hippocampus. Pretreatment with thiamet-G or nonradioactive LSN3316612 reduced brain uptake to a low and uniform concentration in all regions, corresponding to an approximately 90% decrease in distribution volume. Whole-body imaging of rhesus monkeys showed high uptake in kidney, spleen, liver, and testes. In Oga ∆Br mice, brain uptake of 18F-LSN3316612 was reduced by 82% compared with control mice. Peripheral organs were unaffected in Oga ∆Br mice, consistent with loss of OGA expression exclusively in the brain. The effective dose of 18F-LSN3316612 in humans was calculated to be 22 µSv/MBq, which is typical for 18F-labeled radioligands. Conclusion: These results show that 18F-LSN3316612 is an excellent radioligand for imaging and quantifying OGA in rhesus monkeys and mice. On the basis of these data, 18F-LSN3316612 merits evaluation in humans.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Piperidinas/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Tiazóis/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo , Animais , Transporte Biológico , Processamento de Imagem Assistida por Computador , Cinética , Ligantes , Macaca mulatta , Camundongos , Camundongos Knockout , Piperidinas/farmacocinética , Radiometria , Tiazóis/farmacocinética , Distribuição Tecidual
16.
J Pharm Pharmacol ; 71(3): 362-370, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30362574

RESUMO

OBJECTIVES: The aim of this research was to assess regional difference in the intestinal absorption of ranitidine HCl as an indicator for the potential effect of P-glycoprotein (P-gp) efflux transporters. METHODS: In situ rabbit intestinal perfusion was used to investigate absorption of ranitidine HCl, a substrate for P-gp efflux from duodenum, jejunum, ileum and colon. This was conducted both in the presence and absence of piperine as P-gp inhibitor. KEY FINDINGS: Ranitidine HCl was incompletely absorbed from rabbit intestine. The length normalized absorptive clearance (PeA/L) of ranitidine HCl was ranked as colon > duodenum > jejunum > ileum. This is the reverse order of the magnitude of P-gp expression. Coperfusion of piperine with ranitidine HCl significantly increased the PeA/L of ranitidine HCl from jejunum and ileum with no significant change on the absorption from duodenum and colon. This was confirmed by significant reduction in the length required for complete ranitidine HCl absorption from jejunum and ileum in presence piperine. CONCLUSIONS: The results indicate that P-gp transporters play a major role in determining regional difference in intestinal absorption of ranitidine HCl. Thus, the regional absorption of drugs may be taken as an indirect indication for the role of P-gp in intestinal absorption.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Proteínas de Membrana Transportadoras/metabolismo , Alcaloides/metabolismo , Animais , Benzodioxóis/metabolismo , Piperidinas/metabolismo , Alcamidas Poli-Insaturadas/metabolismo , Coelhos
17.
Brain Behav Immun ; 76: 116-125, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30453021

RESUMO

Neuropathic pain is a widespread problem which remains poorly managed by currently available therapeutics. Peripheral nerve injury and inflammation leads to changes at the nerve injury site, including activation of resident and recruited peripheral immune cells, that lead to neuronal central sensitization and pain amplification. The present series of studies tested the effects of peri-sciatic nerve delivery of single doses of adenosine 2A receptor (A2aR) agonists on pain and neuroinflammation. The data provide converging lines of evidence supportive that A2aR agonism at the site of peripheral nerve injury and inflammation is effective in suppressing ongoing neuropathic pain. After A2aR agonism resolved neuropathic pain, a return of pain enhancement (allodynia) was observed in response to peri-sciatic injection of H-89, which can inhibit protein kinase A, and by peri-sciatic injection of neutralizing antibody against the potent anti-inflammatory cytokine interleukin-10. A2aR agonist actions at the nerve injury site suppress neuroinflammation, as reflected by decreased release of interleukin-1ß and nitric oxide, as well as decreased sciatic expression of markers of monocytes/macrophages and inducible nitric oxide synthase. Taken together, the data are supportive that A2aR agonists, acting at the level of peripheral nerve injury, may be of therapeutic value in treating chronic pain of neuroinflammatory origin.


Assuntos
Piperidinas/farmacologia , Nervo Isquiático/efeitos dos fármacos , Neuropatia Ciática/tratamento farmacológico , Animais , Citocinas/metabolismo , Hiperalgesia/tratamento farmacológico , Inflamação/tratamento farmacológico , Injeções Espinhais/métodos , Masculino , Neuralgia/tratamento farmacológico , Traumatismos dos Nervos Periféricos , Piperidinas/metabolismo , Agonistas do Receptor Purinérgico P1/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Purinérgicos P1/metabolismo , Nervo Isquiático/lesões
18.
Chem Biol Drug Des ; 93(5): 818-831, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30582283

RESUMO

The phosphoinositide 3-kinase γ (PI3Kγ) has been verified to be a potential drug target for the treatments of various human physical disorders. Although received lots of attention, the development of PI3Kγ-selective inhibitors is still a challenging subject because of its unique protein structural features. Aiming to uncover the interaction mechanism between the selective inhibitors and PI3Kγ, a series of benzothiazole and thiazolopiperidine PI3Kγ isoform-selective inhibitors were studied with an integrated in silico strategy by combining molecular docking, molecular dynamic simulations, binding free energy calculations, and decomposition analysis. Firstly, three molecular docking models, including rigid receptor docking, induced fit docking (IFD), and quantum mechanical-polarized ligand docking, were respectively, built, and the IFD preliminarily predicted the docking poses of all studied inhibitors and roughly analyzed the binding mechanism. Secondly, four binding complexes with representative inhibitors were selected to perform molecular dynamic simulations and free energy calculations. The predicted binding energies were consistent with the experimental bioactivities and different binding patterns between potent and weak inhibitors were uncovered. Finally, through the Molecular Mechanics/Generalized Born Surface Area binding free energy decomposition, residue-inhibitor interactions spectra were obtained and several key residues contributing to favorable binding were highlighted, which provides valuable information for rational PI3Kγ inhibitor design and modification.


Assuntos
Benzotiazóis/química , Classe Ib de Fosfatidilinositol 3-Quinase/química , Inibidores Enzimáticos/química , Piperidinas/química , Benzotiazóis/metabolismo , Sítios de Ligação , Domínio Catalítico , Classe Ib de Fosfatidilinositol 3-Quinase/metabolismo , Inibidores Enzimáticos/metabolismo , Humanos , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Piperidinas/metabolismo , Termodinâmica
19.
Bioorg Med Chem ; 27(2): 354-363, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30578075

RESUMO

From a screening study of various potential inhibitors for cholinesterases (ChEs), compound (rac)-1 (4-((3-hydroxy-2-oxo-3-phenylindolin-1-yl) methyl) piperidin-1-ium chloride) showed an IC50 of 18 µM for butyrylcholinesterase (BuChE). Herein we present a toxicological and pharmacological evaluation of (rac)-1 to determine its potential for use as an alternative ChE inhibitor for the treatment of Alzheimer's disease. The strategy adopted included in vivo and ex vivo studies with mouse models, Molecular Modelling and Saturation Transfer Difference (STD) NMR studies. Preliminary molecular docking studies were conducted with both (R) and (S)-1 with acetylcholinesterase (AChE) and BuChE, prior to advancing to the mouse model, and indeed favorable interactions were observed, with (R)-1 showing the best binding with AChE and (S)-1 with BuChE. STD-NMR studies were used to successfully validate these results. Toxicological studies were also conducted using the Artemia salina model, with donepezil as reference. It was found that in the in vivo mouse studies that (rac)-1 presented a slightly better inhibition of AChE (0.096 µmol.min-1.mg-1) than donepezil (0.112 µmol.min-1.mg-1) and the same level of inhibition for BuChE as donepezil (0.014 µmol.min-1.mg-1).


Assuntos
Inibidores da Colinesterase/farmacologia , Indóis/farmacologia , Piperidinas/farmacologia , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Animais , Artemia , Encéfalo/metabolismo , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Domínio Catalítico , Inibidores da Colinesterase/química , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/toxicidade , Donepezila/farmacologia , Electrophorus , Humanos , Indóis/química , Indóis/metabolismo , Indóis/toxicidade , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Simulação de Acoplamento Molecular , Piperidinas/química , Piperidinas/metabolismo , Piperidinas/toxicidade , Ligação Proteica , Estereoisomerismo
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 206: 126-134, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30096696

RESUMO

The interactions between 2-{4-[(3S)-piperidin-3-yl] phenyl}-2H-indazole-7-carboxamide (niraparib) and human serum albumin (HSA) were investigated through fluorescence and computational studies. Fluorescence experiments showed that the static quenching mechanism and the binding constant of the HSA-niraparib system at a single binding site was approximately 4 × 104 L mol-1. Thermodynamic constants indicated that the binding of niraparib to HSA was mainly driven by electrostatic interactions. Competition experiments and molecular docking simulations revealed that niraparib bound to site III of HSA. Synchronous fluorescence and Fourier transform infrared spectroscopy (FT-IR) results suggested that interactions between niraparib and HSA could affect the conformation and microenvironment of HSA. Circular dichroism (CD) measurements revealed that the α-helix contents of HSA negligibly increased after binding with niraparib. Molecular dynamics simulations demonstrated the stability of the binary HSA-niraparib system and confirmed that electrostatic forces accounted for the dominant contribution to system energy between HSA and niraparib.


Assuntos
Indazóis/química , Indazóis/metabolismo , Piperidinas/química , Piperidinas/metabolismo , Albumina Sérica Humana/química , Albumina Sérica Humana/metabolismo , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Espectrometria de Fluorescência , Eletricidade Estática
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