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1.
Drug Metab Dispos ; 49(5): 389-394, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33632715

RESUMEN

Fevipiprant, an oral, nonsteroidal, highly selective, reversible, and competitive prostaglandin D2 receptor 2 antagonist, is eliminated by glucuronidation and by direct renal excretion predominantly via organic anion transporter (OAT) 3. This study aimed to assess the effect of simultaneous UDP-glucuronosyltransferase (UGT) and OAT3 inhibition by probenecid on the pharmacokinetics of fevipiprant and its acyl glucuronide (AG) metabolite to support the dosing recommendation of fevipiprant in the presence of drugs inhibiting these pathways; however, phase III clinical trial results did not support its submission. This was a single-center, open-label, single-sequence, two-period crossover study in healthy subjects. Liquid chromatography with tandem mass spectrometry was used to measure concentrations of fevipiprant and its AG metabolite in plasma and urine. In the presence of probenecid, the mean maximum concentrations of fevipiprant increased approximately 1.7-fold, and the area under the concentration-time curve in plasma increased approximately 2.5-fold, whereas the mean apparent volume of distribution and the AG metabolite:fevipiprant ratio decreased. The apparent systemic clearance decreased by approximately 60% and the renal clearance decreased by approximately 88% in the presence of probenecid. Using these data and those from previous studies, the relative contribution of OAT and UGT inhibition to the overall effect of probenecid was estimated. Furthermore, a general disposition scheme for fevipiprant was developed, showing how a perpetrator drug such as probenecid, which interferes with two key elimination pathways of fevipiprant, causes only a moderate increase in exposure and allows estimation of the drug-drug inhibition when only one of the two pathways is inhibited. SIGNIFICANCE STATEMENT: In this drug-drug interaction (DDI) study, probenecid was used as a tool to inhibit both glucuronidation and active renal secretion of fevipiprant. The combination of plasma and urine pharmacokinetic data from this study with available data allowed the development of a quantitative scheme to describe the fate of fevipiprant in the body, illustrating why the DDI effect on fevipiprant is weak-to-moderate even if a perpetrator drug inhibits several elimination pathways.


Asunto(s)
Adyuvantes Farmacéuticos/metabolismo , Ácidos Indolacéticos/metabolismo , Riñón/metabolismo , Tasa de Depuración Metabólica/fisiología , Probenecid/metabolismo , Piridinas/metabolismo , Eliminación Renal/fisiología , Adyuvantes Farmacéuticos/farmacología , Adulto , Estudios Cruzados , Interacciones Farmacológicas/fisiología , Femenino , Humanos , Ácidos Indolacéticos/farmacología , Riñón/efectos de los fármacos , Masculino , Tasa de Depuración Metabólica/efectos de los fármacos , Persona de Mediana Edad , Probenecid/farmacología , Piridinas/farmacología , Eliminación Renal/efectos de los fármacos , Adulto Joven
2.
Prostate ; 79(6): 647-656, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30714183

RESUMEN

BACKGROUND: Paclitaxel (PTX) is a first-line chemotherapeutic drug for the treatment of prostate cancer. However, most patients develop resistance and metastasis, and thus new therapeutic approaches are urgently required. Recent studies have identified widespread anti-tumor effects of zinc (Zn) in various tumor cell lines, especially prostate cancer cells. In this study, we examined the effects of Zn as an adjuvant to PTX in prostate cancer cells. METHODS: PC3 and DU145 cells were treated with different concentrations of Zn and/or PTX. MTT assay was used to detect cell viability. Real-time cell analysis (RTCA) and microscopy were used to observe morphological changes in cells. Western blotting was used to detect the expression of epithelial-mesenchymal transition (EMT)-related proteins. qPCR (reverse transcription-polymerase chain reaction) was used to examine changes in TWIST1 mRNA levels. Cell invasion and migration were detected by scratch and transwell assays. shRNA against TWIST1 was used to knockdown TWIST1. Colony formation assay was used to detect cell proliferation, while Annexin V and propidium iodide (PI) staining was used to detect cell apoptosis. RESULTS: Zn and PTX increased proliferation inhibition in a dose- and time-dependent manner in prostate cancer cells, while Zn increased prostate cancer cell chemosensitivity to PTX. Combined Zn and PTX inhibited prostate cancer cell invasion and migration by downregulating the expression of TWIST1. Furthermore, knockdown of TWIST1 increased the sensitivity of prostate cancer cells to PTX. In addition, Zn and PTX reduced cell proliferation and induced apoptosis in prostate cancer cells. CONCLUSIONS: Our results demonstrated that Zn and PTX combined therapy inhibits EMT by reducing the expression of TWIST1, which reduces the invasion and migration of prostate cancer cells. SiTWIST1 increased the sensitivity of prostate cancer cells to PTX. In addition, with prolonged treatment, Zn and PTX inhibited proliferation and led to prostate cancer cell apoptosis. Therefore, Zn may be a potential adjuvant of PTX in treating prostate cancer and combined treatment may offer a promising therapeutic strategy for prostate cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Paclitaxel/farmacología , Próstata , Neoplasias de la Próstata , Zinc , Adyuvantes Farmacéuticos/metabolismo , Adyuvantes Farmacéuticos/farmacología , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Supervivencia Celular , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Proteínas Nucleares/metabolismo , Próstata/metabolismo , Próstata/patología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteína 1 Relacionada con Twist/metabolismo , Zinc/metabolismo , Zinc/farmacología
3.
Front Immunol ; 13: 904415, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35990686

RESUMEN

The neonatal immune system is distinct from the immune system of older individuals rendering neonates vulnerable to infections and poor responders to vaccination. Adjuvants can be used as tools to enhance immune responses to co-administered antigens. Antibody (Ab) persistence is mediated by long-lived plasma cells that reside in specialized survival niches in the bone marrow, and transient Ab responses in early life have been associated with decreased survival of plasma cells, possibly due to lack of survival factors. Various cells can secrete these factors and which cells are the main producers is still up for debate, especially in early life where this has not been fully addressed. The receptor BCMA and its ligand APRIL have been shown to be important in the maintenance of plasma cells and Abs. Herein, we assessed age-dependent maturation of a broad range of bone marrow accessory cells and their expression of the survival factors APRIL and IL-6. Furthermore, we performed a comparative analysis of the potential of 5 different adjuvants; LT-K63, mmCT, MF59, IC31 and alum, to enhance expression of survival factors and BCMA following immunization of neonatal mice with tetanus toxoid (TT) vaccine. We found that APRIL expression was reduced in the bone marrow of young mice whereas IL-6 expression was higher. Eosinophils, macrophages, megakaryocytes, monocytes and lymphocytes were important secretors of survival factors in early life but undefined cells also constituted a large fraction of secretors. Immunization and adjuvants enhanced APRIL expression but decreased IL-6 expression in bone marrow cells early after immunization. Furthermore, neonatal immunization with adjuvants enhanced the proportion of plasmablasts and plasma cells that expressed BCMA both in spleen and bone marrow. Enhanced BCMA expression correlated with enhanced vaccine-specific humoral responses, even though the effect of alum on BCMA was less pronounced than those of the other adjuvants at later time points. We propose that low APRIL expression in bone marrow as well as low BCMA expression of plasmablasts/plasma cells in early life together cause transient Ab responses and could represent targets to be triggered by vaccine adjuvants to induce persistent humoral immune responses in this age group.


Asunto(s)
Vacunas contra la Tuberculosis , Tuberculosis , Adyuvantes Inmunológicos , Adyuvantes Farmacéuticos/metabolismo , Animales , Antígeno de Maduración de Linfocitos B/metabolismo , Médula Ósea , Supervivencia Celular , Inmunidad Humoral , Interleucina-6/metabolismo , Ratones , Oligodesoxirribonucleótidos/metabolismo , Células Plasmáticas , Toxoide Tetánico , Tuberculosis/metabolismo
4.
Front Immunol ; 13: 916491, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36059475

RESUMEN

Background: Recently, bacterial components were shown to enhance immune responses by shifting immune cell metabolism towards glycolysis and lactic acid production, also known as the Warburg Effect. Currently, the effect of allergen products for immunotherapy (AIT) and commercial vaccines on immune cell metabolism is mostly unknown. Objective: To investigate the effect of AIT products (adjuvanted with either MPLA or Alum) on myeloid dendritic cell (mDC) metabolism and activation. Methods: Bone marrow-derived mDCs were stimulated with five allergoid-based AIT products (one adjuvanted with MPLA, four adjuvanted with Alum) and two MPLA-adjuvanted vaccines and analyzed for their metabolic activation, expression of cell surface markers, and cytokine secretion by ELISA. mDCs were pre-incubated with either immunological or metabolic inhibitors or cultured in glucose- or glutamine-free culture media and subsequently stimulated with the MPLA-containing AIT product (AIT product 1). mDCs were co-cultured with allergen-specific CD4+ T cells to investigate the contribution of metabolic pathways to the T cell priming capacity of mDCs stimulated with AIT product 1. Results: Both the MPLA-containing AIT product 1 and commercial vaccines, but not the Alum-adjuvanted AIT products, activated Warburg metabolism and TNF-α secretion in mDCs. Further experiments focused on AIT product 1. Metabolic analysis showed that AIT product 1 increased glycolytic activity while also inducing the secretion of IL-1ß, IL-10, IL-12, and TNF-α. Both rapamycin (mTOR-inhibitor) and SP600125 (SAP/JNK MAPK-inhibitor) dose-dependently suppressed the AIT product 1-induced Warburg Effect, glucose consumption, IL-10-, and TNF-α secretion. Moreover, both glucose- and glutamine deficiency suppressed secretion of all investigated cytokines (IL-1ß, IL-10, and TNF-α). Glucose metabolism in mDCs was also critical for the (Th1-biased) T cell priming capacity of AIT product 1-stimulated mDCs, as inhibition of mTOR signaling abrogated their ability to induce Th1-responses. Conclusion: The AIT product and commercial vaccines containing the adjuvant MPLA were shown to modulate the induction of immune responses by changing the metabolic state of mDCs. Better understanding the mechanisms underlying the interactions between cell metabolism and immune responses will allow us to further improve vaccine development and AIT.


Asunto(s)
Alérgenos , Vacunas , Adyuvantes Inmunológicos/farmacología , Adyuvantes Farmacéuticos/metabolismo , Adyuvantes Farmacéuticos/farmacología , Células Dendríticas , Glucosa/metabolismo , Factores Inmunológicos/farmacología , Inmunoterapia , Interleucina-10 , Serina-Treonina Quinasas TOR/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Vacunas/farmacología
5.
Front Immunol ; 13: 990900, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36131928

RESUMEN

Recent studies have shown that corn-derived cationic α-D-glucan nanoparticles, known as Nano-11, significantly increase the immune response when used as a vaccine adjuvant in mice and in pigs. Furthermore, the nanoparticles can be formulated with other immunostimulators such as poly(I:C), which further enhances the immune response. The current experiments were aimed at elucidating the mechanism of action of Nano-11 alone and in combination with poly(I:C). The effect of these adjuvants on porcine monocyte-derived dendritic cells (Mo-DCs) was determined by RNA-sequencing, supplemented with flow cytometry, cytokine analysis, and Western blots. Adsorption of poly(I:C) to Nano-11 reduced its cytotoxicity for Mo-DCs. Exposure of Mo-DCs to Nano-11 and Nano-11/poly(I:C) induced differential expression of 979 and 2016 genes, respectively. Gene Ontology enrichment and KEGG pathway analysis revealed many changes in gene expression related to inflammation, innate immunity, immune response to infections, and metabolism. Nano-11 and Nano-11/poly(I:C) induced maturation of the Mo-DCs as indicated by increased expression of costimulatory molecules and MHC II. Increased expression of genes downstream of p38 MAPK activation revealed a role for this signaling pathway in the activation of Mo-DCs by the adjuvants. This was confirmed by Western blot and inhibition of TNF-secretion upon incubation with the p38 inhibitor SB203580. These experiments provide insights into the mechanism of action of the novel adjuvants Nano-11 and Nano-11/poly(I:C).


Asunto(s)
Glucanos , Nanopartículas , Adyuvantes Inmunológicos/metabolismo , Adyuvantes Inmunológicos/farmacología , Adyuvantes Farmacéuticos/metabolismo , Adyuvantes Farmacéuticos/farmacología , Animales , Citocinas/metabolismo , Células Dendríticas , Glucanos/farmacología , Ratones , Poli I-C/metabolismo , Poli I-C/farmacología , ARN/metabolismo , Porcinos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
6.
Mol Pharm ; 8(5): 1955-61, 2011 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-21793576

RESUMEN

Multiple dysregulated pathways in tumors necessitate targeting multiple oncogenic elements by combining orthogonal therapeutic moieties like short-interfering RNAs (siRNA) and drug molecules in order to achieve a synergistic therapeutic effect. In this manuscript, we describe the synthesis of cyclodextrin-modified dendritic polyamines (DexAMs) and their application as a multicomponent delivery vehicle for translocating siRNA and anticancer drugs. The presence of ß-cyclodextrins in our DexAMs facilitated complexation and intracellular uptake of hydrophobic anticancer drugs, suberoylanilide hydroxamic acid (SAHA) and erlotinib, whereas the cationic polyamine backbone allowed for electrostatic interaction with the negatively charged siRNA. The DexAM complexes were found to have minimal cytotoxicity over a wide range of concentrations and were found to efficiently deliver siRNA, thereby silencing the expression of targeted genes. As a proof of concept, we demonstrated that upon appropriate modification with targeting ligands, we were able to simultaneously deliver multiple payloads--siRNA against oncogenic receptor, EGFRvIII and anticancer drugs (SAHA or erlotinib)--efficiently and selectively to glioblastoma cells. Codelivery of siRNA-EGFRvIII and SAHA/erlotinib in glioblastoma cells was found to significantly inhibit cell proliferation and induce apoptosis, as compared to the individual treatments.


Asunto(s)
Adyuvantes Farmacéuticos/metabolismo , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Portadores de Fármacos/farmacología , ARN Interferente Pequeño/metabolismo , Animales , Antineoplásicos/agonistas , Antineoplásicos/química , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Composición de Medicamentos , Receptores ErbB/antagonistas & inhibidores , Clorhidrato de Erlotinib , Silenciador del Gen , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Humanos , Ácidos Hidroxámicos/agonistas , Ácidos Hidroxámicos/química , Ácidos Hidroxámicos/farmacología , Ligandos , Proteínas de Neoplasias/antagonistas & inhibidores , Células PC12 , Tamaño de la Partícula , Quinazolinas/agonistas , Quinazolinas/química , Quinazolinas/farmacología , Ratas , Vorinostat
7.
Br J Clin Pharmacol ; 69(2): 167-78, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20233180

RESUMEN

AIMS: Probenecid influences transport processes of drugs at several sites in the body and decreases elimination of several quinolones. We sought to explore extent, time course, and mechanism of the interaction between ciprofloxacin and probenecid at renal and nonrenal sites. METHODS: A randomized, two-way crossover study was conducted in 12 healthy volunteers (in part previously published Clin Pharmacol Ther 1995; 58: 532-41). Subjects received 200 mg ciprofloxacin as 30-min intravenous infusion without and with 3 g probenecid divided into five oral doses. Drug concentrations were analysed by liquid chromatography-tandem mass spectrometry and high-performance liquid chromatography. Ciprofloxacin and its 2-aminoethylamino-metabolite (M1) in plasma and urine with and without probenecid were modelled simultaneously with WinNonlin. RESULTS: Data are ratio of geometric means (90% confidence intervals). Addition of probenecid reduced the median renal clearance from 23.8 to 8.25 l h(-1)[65% reduction (59, 71), P < 0.01] for ciprofloxacin and from 20.5 to 8.26 l h(-1) (66% reduction (57, 73), P < 0.01] for M1 (estimated by modelling). Probenecid reduced ciprofloxacin nonrenal clearance by 8% (1, 14) (P < 0.08). Pharmacokinetic modelling indicated competitive inhibition of the renal tubular secretion of ciprofloxacin and M1 by probenecid. The affinity for the renal transporter was 4.4 times higher for ciprofloxacin and 3.6 times higher for M1 than for probenecid, based on the molar ratio. Probenecid did not affect volume of distribution of ciprofloxacin or M1, nonrenal clearance or intercompartmental clearance of ciprofloxacin. CONCLUSIONS: Probenecid inhibited the renal tubular secretion of ciprofloxacin and M1, probably by a competitive mechanism and due to reaching >100-fold higher plasma concentrations. Formation of M1, nonrenal clearance and distribution of ciprofloxacin were not affected.


Asunto(s)
Adyuvantes Farmacéuticos/farmacocinética , Antiinfecciosos/farmacocinética , Ciprofloxacina/farmacocinética , Túbulos Renales/metabolismo , Probenecid/farmacocinética , Adyuvantes Farmacéuticos/administración & dosificación , Adyuvantes Farmacéuticos/metabolismo , Administración Oral , Análisis de Varianza , Antiinfecciosos/administración & dosificación , Antiinfecciosos/metabolismo , Ciprofloxacina/administración & dosificación , Ciprofloxacina/metabolismo , Estudios Cruzados , Interacciones Farmacológicas , Femenino , Humanos , Inyecciones Intravenosas , Pruebas de Función Renal , Masculino , Tasa de Depuración Metabólica/efectos de los fármacos , Modelos Biológicos , Probenecid/administración & dosificación , Probenecid/metabolismo , Estadística como Asunto
8.
J Med Chem ; 62(19): 8665-8681, 2019 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-31063379

RESUMEN

Multiple approaches have been developed to combat bacterial resistance. However, the combination of antibiotic resistance mechanisms by bacteria and the limited number of effective antibiotics available decreases the effective interventions for the treatment of current bacterial infections. This review covers the many ways that bacteria resist antibiotics including antibiotic target modification, the use of efflux pumps, and antibiotic inactivation. As a pertinent example, the use of beta lactamase inhibitors in combination with ß-lactam containing antibiotics is discussed in detail. The solution to emerging antibiotic resistance may involve combination therapies of existing antibiotics and potentiating adjuvants, which re-empower the antibiotic agent to become efficacious against the resistant strain of interest. We report herein that a reasoned adjuvant design permits one to perform polypharmacy on bacteria by not only providing greater internal access to the codosed antibiotics but also by de-energizing the efflux pumps used by the bacteria to escape antibiotic action.


Asunto(s)
Antibacterianos/metabolismo , Bacterias/metabolismo , Proteínas Bacterianas/metabolismo , Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Transportadoras de Casetes de Unión a ATP/metabolismo , Adyuvantes Farmacéuticos/química , Adyuvantes Farmacéuticos/metabolismo , Adyuvantes Farmacéuticos/farmacología , Antibacterianos/farmacología , Pared Celular/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/genética , Inhibidores de beta-Lactamasas/química , Inhibidores de beta-Lactamasas/metabolismo , beta-Lactamasas/química , beta-Lactamasas/metabolismo
9.
Drug Deliv ; 25(1): 1858-1864, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30338713

RESUMEN

Puerarin (PUE) and tetramethylpyrazine (TMP) are central nervous system (CNS) drugs used in cerebrovascular diseases. Poor brain-blood barrier (BBB) permeability limited their clinical application. Borneol and α-asarone have been proposed as an oral brain-targeting enhancer. In this study, we aimed to first evaluate the 'orifice-opening' effect of borneol and α-asarone, both aromatic resuscitation drugs, on improvement of brain delivery of PUE and TMP and second to investigate whether the enhancing effects were associated with adenosine receptors (ARs)-mediated trans-BBB pathway. In vitro BBB model was established and borneol and α-asarone significantly increased the cumulative amount of permeated PUE and TMP and the enhancing effects could be counteracted by AR inhibitors. Borneol and α-asarone could decrease expression of ZO-1, an important BBB junction protein, but inversely increase the expression of A1AR and A2AAR. In vivo pharmacokinetic study also confirmed that oral co-administration of borneol or α-asarone significantly increased AUCbrain for PUE and TMP. These results suggested that borneol and α-asarone are both effective adjuvant agents for delivery of PUE and TMP to the brain.


Asunto(s)
Adyuvantes Farmacéuticos , Anisoles/química , Barrera Hematoencefálica , Canfanos/química , Receptores Purinérgicos P1/metabolismo , Adyuvantes Farmacéuticos/metabolismo , Adyuvantes Farmacéuticos/farmacología , Derivados de Alilbenceno , Animales , Transporte Biológico , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Línea Celular , Humanos , Isoflavonas/farmacología , Masculino , Ratones , Permeabilidad , Pirazinas/farmacología , Ratas Sprague-Dawley
10.
Cell Mol Biol (Noisy-le-grand) ; 53(1): 26-47, 2007 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-17519110

RESUMEN

Health hazards caused by heavy metals have become a great concern to the population. Lead and arsenic are one of the most important current global environmental toxicants. Their toxic manifestations are being considered caused primarily due to the imbalance between pro-oxidant and antioxidant homeostasis and also due to a high affinity of these metals for thiol groups on functional proteins. They also interfere with a number of other body functions and are known to affect central nervous system (CNS), hematopoietic system, liver and kidneys and produce serious disorders. They produce both acute and chronic poisoning, of which chronic poisoning is more dangerous as its very difficult to revert back to normal condition after chronic exposure to these insidious metals present in our life. Despite many years of research, we are still far from an effective treatment of chronic plumbism and arsenicosis. Current approved treatment lies in the administration of chelating agents that forms an insoluble complex with the metal and removes it. They have been used clinically as antidotes for treating acute and chronic poisoning. The most widely used chelating agents are calcium disodium ethylenediamine tetra acetic acid (CaNa2EDTA), D-penicillamine and British anti-lewisite (BAL). Meso 2,3 dimercaptosuccinic acid (DMSA), an analogue of BAL, has been tried successfully in animals as well as in humans. But it is unable to remove the metal from intracellular sites. Effective chelation therapy for intoxication by heavy metals depends on whether the chelating agents are able to reach the intracellular site where the heavy metal is firmly bound. One of the important approaches has been the use of combination therapy. This includes use of structurally different chelators or a combination of an adjuvant/ antioxidant/ herbal extracts and a chelator to provide better clinical/ biochemical recovery. A number of other strategies have been suggested to minimize the numerous problems. This article presents the recent development made in this area with possible directions for future research.


Asunto(s)
Arsénico/metabolismo , Quelantes/metabolismo , Radicales Libres/metabolismo , Plomo/metabolismo , Acetilcisteína/metabolismo , Adyuvantes Farmacéuticos/metabolismo , Animales , Antioxidantes/metabolismo , Arsénico/toxicidad , Intoxicación por Arsénico/fisiopatología , Intoxicación por Arsénico/terapia , Ácido Ascórbico/metabolismo , Calcio/metabolismo , Quelantes/química , Quelantes/uso terapéutico , Radicales Libres/toxicidad , Humanos , Plomo/toxicidad , Intoxicación por Plomo/fisiopatología , Intoxicación por Plomo/terapia , Melatonina/metabolismo , Metales/metabolismo , Micronutrientes/metabolismo , Estructura Molecular , Succímero/química , Succímero/metabolismo , Succímero/uso terapéutico , Taurina/metabolismo , Ácido Tióctico/metabolismo , Unitiol/química , Unitiol/metabolismo , Unitiol/uso terapéutico , Vitamina E/metabolismo
11.
J Pharm Sci ; 105(6): 1829-1836, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27238481

RESUMEN

The adsorption mechanism of antigen on aluminum adjuvant can affect antigen elution at the injection site and hence the immune response. Our aim was to evaluate adsorption onto aluminum hydroxide (AH) by ligand exchange and electrostatic interactions of model proteins and antigens, bovine serum albumin (BSA), ß-casein, ovalbumin (OVA), hepatitis B surface antigen, and tetanus toxin (TT). A high-throughput screening platform was developed to measure adsorption isotherms in the presence of electrolytes and ligand exchange by a fluorescence-spectroscopy method that detects the catalysis of 6,8-difluoro-4-methylumbelliferyl phosphate by free hydroxyl groups on AH. BSA adsorption depended on predominant electrostatic interactions. Ligand exchange contributes to the adsorption of ß-casein, OVA, hepatitis B surface antigen, and TT onto AH. Based on relative surface phosphophilicity and adsorption isotherms in the presence of phosphate and fluoride, the capacities of the proteins to interact with AH by ligand exchange followed the trend: OVA < ß-casein < BSA < TT. This could be explained by both the content of ligands available in the protein structure for ligand exchange and the antigen's molecular weight. The high-throughput screening platform can be used to better understand the contributions of ligand exchange and electrostatic attractions governing the interactions between an antigen adsorbed onto aluminum-containing adjuvant.


Asunto(s)
Hidróxido de Aluminio/química , Hidróxido de Aluminio/metabolismo , Antígenos/análisis , Antígenos/metabolismo , Ensayos Analíticos de Alto Rendimiento/métodos , Adyuvantes Farmacéuticos/química , Adyuvantes Farmacéuticos/metabolismo , Adsorción , Animales , Caseínas/análisis , Caseínas/metabolismo , Bovinos , Evaluación Preclínica de Medicamentos/métodos , Antígenos de Superficie de la Hepatitis B/análisis , Antígenos de Superficie de la Hepatitis B/metabolismo , Humanos , Ovalbúmina/análisis , Ovalbúmina/metabolismo , Albúmina Sérica Bovina/análisis , Albúmina Sérica Bovina/metabolismo , Toxoide Tetánico/análisis , Toxoide Tetánico/metabolismo
12.
J Pharm Sci ; 104(2): 627-39, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25581103

RESUMEN

During transport and storage, vaccines may be exposed to temperatures outside of the range recommended for storage, potentially causing efficacy losses. To better understand and prevent such losses, dominant negative inhibitor (DNI), a recombinant protein antigen for a candidate vaccine against anthrax, was formulated as a liquid and as a glassy lyophilized powder with the adjuvants aluminum hydroxide and glycopyranoside lipid A (GLA). Freeze-thawing of the liquid vaccine caused the adjuvants to aggregate and decreased its immunogenicity in mice. Immunogenicity of liquid vaccines also decreased when stored at 40°C for 8 weeks, as measured by decreases in neutralizing antibody titers in vaccinated mice. Concomitant with efficacy losses at elevated temperatures, changes in DNI structure were detected by fluorescence spectroscopy and increased deamidation was observed by capillary isoelectric focusing (cIEF) after only 1 week of storage of the liquid formulation at 40°C. In contrast, upon lyophilization, no additional deamidation after 4 weeks at 40°C and no detectable changes in DNI structure or reduction in immunogenicity after 16 weeks at 40°C were observed. Vaccines containing aluminum hydroxide and GLA elicited higher immune responses than vaccines adjuvanted with only aluminum hydroxide, with more mice responding to a single dose.


Asunto(s)
Adyuvantes Farmacéuticos/química , Hidróxido de Aluminio/química , Vacunas contra el Carbunco/química , Lípido A/química , Adyuvantes Farmacéuticos/metabolismo , Hidróxido de Aluminio/metabolismo , Animales , Vacunas contra el Carbunco/metabolismo , Estabilidad de Medicamentos , Femenino , Liofilización/métodos , Congelación , Vidrio , Lípido A/metabolismo , Ratones , Ratones Endogámicos BALB C
13.
J Pharm Sci ; 104(2): 557-65, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25470455

RESUMEN

Aluminum-containing salts are important adjuvants in the formulations of many licensed human vaccines. However, in the early stage of the design of a new vaccine, a thorough understanding of the adsorption mechanisms of an antigen onto an aluminum salt is required. Therefore, we have developed a robust, rapid, and reproducible high-throughput screening (HTS) platform to study the adsorption capacity of aluminum-containing vaccines. The adsorption isotherms on aluminum hydroxide and aluminum phosphate of two model proteins, ß-casein, and bovine serum albumin, were evaluated using a liquid handling system, which permitted rapid sample preparation in a small volume without nonspecific adsorption. Highly reproducible adsorption capacities and adsorptive coefficients were estimated based on the Langmuir model. To demonstrate the potential of this HTS platform, we evaluated the adsorption isotherms for two antigens, hepatitis B surface antigen and a pneumococcal serotype polysaccharide conjugated to a protein-D carrier, onto aluminum-containing vaccines at either a constant protein or a constant aluminum concentration. The automated assay enabled the rapid quantification of antigen adsorption with a significant reduction in operator workload and reagent use. This platform should accelerate data acquisition during the development of a new vaccine.


Asunto(s)
Adyuvantes Farmacéuticos/análisis , Aluminio/análisis , Antígenos/análisis , Ensayos Analíticos de Alto Rendimiento/métodos , Adyuvantes Farmacéuticos/metabolismo , Adsorción/fisiología , Aluminio/metabolismo , Animales , Antígenos/metabolismo , Caseínas/análisis , Caseínas/metabolismo , Bovinos , Humanos , Albúmina Sérica Bovina/análisis , Albúmina Sérica Bovina/metabolismo
14.
Cancer Chemother Pharmacol ; 45(4): 298-304, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10755318

RESUMEN

PURPOSE: N,N-diethyl-2-[4-(phenylmethyl)phenoxy]ethanamine HCl (DPPE), an intracellular histamine (HA) antagonist with chemopotentiating and cytoprotective properties, is currently in phase 2 and 3 clinical trials in breast and prostate cancer. DPPE modulates growth at in vitro concentrations that antagonize HA binding to cytochromes P450 in rat liver microsomes. HA inhibits P450 metabolism of some drugs. Recent in vitro studies in human colon cancer cells have linked DPPE enhancement of paclitaxel, doxorubicin and vinblastine cytotoxicity to inhibition of the P-glycoprotein (P-gp) pump. Many substrates of P-gp are also substrates of CYP3A4, a P450 isozyme that metabolizes a variety of antineoplastic agents and is highly expressed in some malignant tissues. Therefore, we assessed whether (a) DPPE and HA interact at CYP3A4 and other P450 human isozymes, and (b) DPPE inhibits the catalytic activity of CYP3A4. METHODS: Using spectral analysis, we measured DPPE and HA binding to insect microsomes that express human P450 isozymes 1A1, 2B6, 2D6 or 3A4. Employing thin-layer chromatography, we assessed the metabolism of DPPE by each isozyme and DPPE inhibition of testosterone metabolism by CYP3A4 and by rat liver microsomes. RESULTS: (1) DPPE evoked "type I" (substrate site binding) absorbance-difference spectra with CYP2D6 (K(S) = 4.1 +/- 0.4 microM), CYP3A4 (K(S) = 31 +/- 15 microM) and CYP1A1 (K(S) = 40 +/- 9 microM), but not with CYP2B6. (2) In correspondence with the binding studies, DPPE was metabolized by CYP2D6, CYP3A4 and CYP1A1; no metabolism occurred with CYP2B6. (3) HA evoked "type II" (heme iron binding) absorbance-difference spectra with all four isozymes, with K(S) values in the range 80-600 microM. DPPE inhibited HA (600 microM) binding to CYP2D6 (IC50 = 4 microM, 95% CI= 1.8-8.9 microM) and CYP1A1 (IC50 = 135 microM: 95% CI = 100-177 microM), but stimulated HA (500 and 1000 microM) binding to CYP3A4 (EC50 = 155 microM, 95% CI = 104-231 microM). DPPE did not affect HA binding to CYP2B6. (4) DPPE inhibited the metabolism of testosterone by CYP3A4. The concentration/effect curve was biphasic: DPPE inhibited metabolism by 30% at the first site (IC50 = 3 microM, 95% CI = 0.5-25.5 microM), and an additional 70% inhibition occurred at the second site (IC50 = 350 microM, 95% CI = 215-570 microM). A similar result was observed with rat liver microsomes. CONCLUSION: DPPE is a substrate for CYP3A4, CYP2D6 and CYP1A1, but not CYP2B6. DPPE inhibits testosterone metabolism by interacting at two sites on CYP3A4, the first correlating with its K(S) value to bind the substrate site and the second, with its EC50 value to enhance HA binding to the heme iron. We postulate that (1) the inhibitory effect of DPPE on CYP3A4 activity is mediated directly at the substrate site and indirectly by its enhancement of the binding of HA to the heme moiety; (2) in tumor cells that express high constitutive levels of CYP3A4, potentiation of chemotherapy cytotoxicity by DPPE results, in part, from inhibition of CYP3A4-mediated metabolism and P-gp-mediated efflux of antineoplastic drugs; (3) in normal cells that express low constitutive levels of the isozyme, cytoprotection by DPPE results, in part, from induction of CYP3A4 and P-gp, resulting in an increase both in metabolism and efflux of antineoplastic drugs.


Asunto(s)
Adyuvantes Farmacéuticos/farmacología , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Histamina/metabolismo , Oxigenasas de Función Mixta/metabolismo , Éteres Fenílicos/farmacología , Adyuvantes Farmacéuticos/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Cromatografía en Capa Delgada , Citocromo P-450 CYP3A , Técnicas In Vitro , Indicadores y Reactivos , Isoenzimas/metabolismo , Masculino , Microsomas Hepáticos/metabolismo , Éteres Fenílicos/metabolismo , Ratas , Ratas Sprague-Dawley , Espectrofotometría Ultravioleta , Testosterona/metabolismo
15.
J Control Release ; 93(2): 95-103, 2003 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-14636716

RESUMEN

Thiolated polymers (= thiomers) in combination with reduced glutathione (GSH) were shown to improve the uptake of hydrophilic macromolecules from the GI tract. The mechanism responsible for this permeation enhancing effect seems to be based on the thiol groups of the polymer. These groups inhibit protein tyrosine phosphatase, being involved in the closing process of tight junctions, via a GSH-mediated mechanism. The strong permeation enhancing effect of various thiomer/GSH systems such as poly(acrylic acid)-cysteine/GSH or chitosan-4-thio-butylamidine (chitosan-TBA)/GSH could be shown via permeation studies on freshly excised intestinal mucosa in Ussing-type chambers. Furthermore, the efficacy of the system was also shown in vivo. By utilizing poly(acrylic acid)-cysteine/GSH as carrier matrix, an absolute oral bioavailability for low molecular weight heparin of 19.9 +/- 9.3% and a pharmacological efficacy--calculated on the basis of the areas under the reduction in serum glucose levels of the oral formulation versus subcutaneous (s.c.) injection-for orally given insulin of 7% could be achieved. The incorporation of salmon calcitonin in chitosan-TBA/GSH led on the other hand to a pharmacological efficacy based on the areas under the reduction in plasma calcium levels of the oral thiomer formulation versus intravenous (i.v.) injection of 1.3%. Because of this high efficacy (i), the possibility to combine thiomer/GSH systems with additional low molecular weight permeation enhancers acting in other ways (ii) and minimal toxicological risks as these polymers are not absorbed from the GI tract (iii), thiolated polymers represent a promising novel tool for the oral administration of hydrophilic macromolecules.


Asunto(s)
Adyuvantes Farmacéuticos/química , Administración Oral , Glutatión/metabolismo , Sustancias Macromoleculares , Permeabilidad , Polímeros/química , Compuestos de Sulfhidrilo/metabolismo , Adyuvantes Farmacéuticos/metabolismo , Animales , Transporte Biológico , Glutatión/química , Humanos , Polímeros/metabolismo , Compuestos de Sulfhidrilo/química
16.
J Pharm Biomed Anal ; 16(7): 1179-87, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9571535

RESUMEN

A new nonaqueous topical minoxidil formulation containing SEPA (2-n-nonyl-1,3-dioxolane) for enhancement of percutaneous absorption was under evaluation. SEPA does not have chromophore for either ultraviolet or fluorescence detection using liquid chromatography and has no functional groups for derivatization. Therefore, a direct gas-chromatographic method with flame-ionization detection (GC-FID) was developed. Owing to the limited detection response of the FID detection, it needs a selective and concentrated extract for GC-FID analysis to improve the assay sensitivity to meet the requirement for pharmacokinetic evaluation after topical application. In addition, SEPA is a very volatile compound. Any extraction procedures involving evaporation will result in a poor recovery. The application of solid-phase extraction (SPE) makes it possible to achieve a selective and a 10-fold concentrated extract with an absolute extraction recovery of approximately 90%, which greatly improved the assay sensitivity. This method involved the extraction of SEPA and the internal standard (2-n-heptyl-1,3-dioxolane) from serum (0.1-1 ml) with 100 microliter of hexane-chloroform (1:1, v:v) using a 50 mg 1.0 ml-1 phenyl SPE column (Varian, Harbor City, CA, USA), followed by direct GC-FID analysis on a fused-silica column chemically bonded with cross-linked methyl silicone gum phase (Hewlett Packard Ultra-1, 12 m x 0.2 mm x 0.33 micron, Avondale, PA, USA). The assay demonstrated a lower limit of quantitation of 2.5 ng ml-1 and a linear range of 2.5 to 250 ng ml-1 with intra- and inter-assay precision and accuracy of < or = 10%.


Asunto(s)
Adyuvantes Farmacéuticos/metabolismo , Cromatografía de Gases/métodos , Dioxolanos/sangre , Absorción , Administración Tópica , Alopecia/tratamiento farmacológico , Animales , Sistemas de Liberación de Medicamentos , Estabilidad de Medicamentos , Humanos , Minoxidil/administración & dosificación , Minoxidil/sangre , Minoxidil/uso terapéutico , Conejos , Ratas , Sensibilidad y Especificidad
17.
Methods Find Exp Clin Pharmacol ; 8(1): 15-8, 1986 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3702541

RESUMEN

The pharmaceutical properties of quinonyl-MDP-66 were discussed with special reference to the stability of oil-in-water emulsion, distribution capacity into regional lymph nodes and tumor regressive activity. The oil-in-water emulsion of quinonyl-MDP-66, which was prepared by treatment of quinonyl-MDP-66 with squalane (25 x) and emulsified with aqueous solution of 5% HCO-60 and 5.6% d-mannitol, was kept in lyophylized state and used after reconstitution by the addition of water before use. The reconstituted suspension of quinonyl-MDP-66 in oil-in-water emulsion was stable for more than 24 hrs. The oil-in-water emulsion of quinonyl-MDP-66 as prepared above was effective for the distribution of quinonyl-MDP-66 into regional lymph node in rats and for the regression of line 10 hepatoma in strain 2 guinea pigs by intralesional injection.


Asunto(s)
Acetilmuramil-Alanil-Isoglutamina/análogos & derivados , Antineoplásicos/farmacología , Neoplasias Hepáticas Experimentales/patología , Acetilmuramil-Alanil-Isoglutamina/metabolismo , Acetilmuramil-Alanil-Isoglutamina/farmacología , Adyuvantes Farmacéuticos/metabolismo , Adyuvantes Farmacéuticos/farmacología , Animales , Antineoplásicos/metabolismo , Línea Celular , Fenómenos Químicos , Química , Emulsiones , Femenino , Cobayas , Neoplasias Hepáticas Experimentales/metabolismo , Ganglios Linfáticos/metabolismo , Masculino , Trasplante de Neoplasias , Factores de Tiempo
19.
Drug Deliv ; 21(2): 140-7, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24559517

RESUMEN

Studies on preparation of in situ gel formulations containing diphtheria toxoid as the model active substance and their intranasal administration have been conducted in this study. The objective of mucosal vaccination is to stimulate both systemic and mucosal immune responses. In situ gel formulations were prepared by using, in different ratios, mixtures of Poloxamer 407 and Poloxamer 188 polymers, which gelate in a temperature-dependent manner, and mucoadhesive polymers carbopol 934, hydroxypropyl methyl cellulose, hydroxypropyl cellulose or chitosan. Following pre-formulation studies, F1, F2, F3, F4, F5, F6 and F7 formulations, which gelate at intervals and temperatures in accordance with nasal temperatures, were subjected to more comprehensive studies. For this purpose, organoleptic characteristics of the formulations were identified, their pH and mucoadhesive potencies were measured and rheological behaviors were characterized. Calculated amounts of diphtheria toxoid were added to formulations after optimization of formulations was achieved, and assay and in vitro release studies were carried out. Formulations coded F3 and F7 were considered to be superior to other formulations given the in vitro test results. Therefore, these formulations were tested in guinea pigs to determine immune responses, which they would produce following intranasal and subcutaneous administration. Absorbance values of ELISA tests and antibody neutralization test showed that formulations coded F3 and F7 were unable to stimulate adequate systemic immune response when either of the formulations was administered alone intranasally, whereas F7 resulted in significantly increased neutralizing antibody titers with intranasal administration as a booster dose following subcutaneous administration.


Asunto(s)
Adyuvantes Farmacéuticos/administración & dosificación , Adyuvantes Farmacéuticos/metabolismo , Toxoide Diftérico/administración & dosificación , Toxoide Diftérico/metabolismo , Mucosa Nasal/efectos de los fármacos , Mucosa Nasal/metabolismo , Adyuvantes Farmacéuticos/química , Administración Intranasal , Animales , Química Farmacéutica , Toxoide Diftérico/química , Evaluación Preclínica de Medicamentos/métodos , Geles , Cobayas
20.
Folia Neuropathol ; 51(2): 132-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23821385

RESUMEN

Opiate analgesics like morphine or fentanyl are the most widely used medicines for relieving severe acute or chronic pain, including cancer pain. Unfortunately, chronic pain treatment is associated with fast development of tolerance that creates the need to escalate the treatment doses. In addition, opiates may stimulate progression of cancer. Therefore, a new type of effective analgesic especially designed for chronic cancer pain treatment is needed. In this paper, a new opioid peptide analogue has been described as a new analgesic. The compound is characterized by very high agonist affinities to MOR and also high, but ten times lower affinity to DOR. Affinity to hNK1 as an antagonist is on the level of C-terminal hexapeptide fragment analogue of Substance P. The compound expressed reasonable antiproliferative properties toward various cancer cells. Interestingly, the peptide did not interfere with the proliferation of fibro-blasts. Therefore, the compound should be considered as a new analgesic for treatment of cancer-related pains with adjuvant anticancer properties which may support cancer treatments.


Asunto(s)
Analgésicos Opioides/farmacología , Antineoplásicos/farmacología , Antagonistas de Narcóticos/farmacología , Receptores Opioides/agonistas , Taquicininas/antagonistas & inhibidores , Adyuvantes Farmacéuticos/síntesis química , Adyuvantes Farmacéuticos/metabolismo , Adyuvantes Farmacéuticos/farmacología , Analgésicos Opioides/síntesis química , Analgésicos Opioides/metabolismo , Animales , Antineoplásicos/síntesis química , Antineoplásicos/metabolismo , Células CHO , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Quimioterapia Adyuvante/métodos , Cricetinae , Cricetulus , Humanos , Antagonistas de Narcóticos/síntesis química , Antagonistas de Narcóticos/metabolismo , Unión Proteica/fisiología , Ratas Wistar , Receptores de Neuroquinina-1/fisiología , Receptores Opioides/metabolismo , Taquicininas/fisiología
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