RESUMEN
BACKGROUND: The glutamatergic neurotransmission has important role in the pathomechanism of primary headache disorders. The kynurenine metabolites derived from catabolism of tryptophan (Trp) have significant involvement not only in glutamatergic processes, but also in the neuroinflammation, the oxidative stress and the mitochondrial dysfunctions. Previously we identified a depressed peripheral Trp metabolism in interictal period of episodic migraineurs, which prompted us to examine this pathway in patients with episodic cluster headache (CH) as well. Our aims were to compare the concentrations of compounds both in headache-free and attack periods, and to find correlations between Trp metabolism and the clinical features of CH. Levels of 11 molecules were determined in peripheral blood plasma of healthy controls (n = 22) and interbout/ictal periods of CH patients (n = 24) by neurochemical measurements. FINDINGS: Significantly decreased L-kynurenine (KYN, p < 0.01), while increased quinolinic acid (QUINA, p < 0.005) plasma concentrations were detected in the interbout period of CH patients compared to healthy subjects. The levels of KYN are further reduced during the ictal period compared to the controls (p < 0.006). There was a moderate, negative correlation between disease duration and interbout QUINA levels (p < 0.048, R = - 0.459); and between the total number of CH attacks experienced during the lifetime of patients and the interbout KYN concentrations (p < 0.024, R = - 0.516). Linear regression models revealed negative associations between age and levels of Trp, kynurenic acid, 3-hdyroxyanthranilic acid and QUINA in healthy control subjects, as well as between age and ictal level of anthranilic acid. CONCLUSIONS: Our results refer to a specifically altered Trp metabolism in CH patients. The onset of metabolic imbalance can be attributed to the interbout period, where the decreased KYN level is unable to perform its protective functions, while the concentration of QUINA, as a toxic compound, increases. These processes can trigger CH attacks, which may be associated with glutamate excess induced neurotoxicity, neuroinflammation and oxidative stress. Further studies are needed to elucidate the exact functions of these molecular alterations that can contribute to identify new, potential biomarkers in the therapy of CH.
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Cefalalgia Histamínica , Quinurenina , Humanos , Quinurenina/metabolismo , Enfermedades Neuroinflamatorias , Triptófano/metabolismo , Ácido QuinurénicoRESUMEN
Facile syntheses of 3-O-carbamoyl, -sulfamoyl, or -pivaloyl derivatives of 13α-oestrone and its 17-deoxy counterpart have been carried out. Microwave-induced, Ni-catalysed Suzuki-Miyaura couplings of the newly synthesised phenol esters with phenylboronic acid afforded 3-deoxy-3-phenyl-13α-oestrone derivatives. The carbamate and pivalate esters proved to be suitable for regioselective arylations. 2-(4-Substituted) phenyl derivatives were synthesised via Pd-catalysed, microwave-assisted C-H activation reactions. An efficient, one-pot, tandem methodology was elaborated for the introduction of the carbamoyl or pivaloyl group followed by regioselective C-2-arylation and subsequent removal of the directing group. The antiproliferative properties of the novel 13α-oestrone derivatives were evaluated in vitro on five human adherent cancer cell lines of gynaecological origin. 3-Sulfamate derivatives displayed substantial cell growth inhibitory potential against certain cell lines. The newly identified antiproliferative compounds having hormonally inactive core might be promising candidates for the design of more active anticancer agents.
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Antineoplásicos/farmacología , Estrona/farmacología , Elementos de Transición/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Catálisis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Estrona/análogos & derivados , Estrona/química , Humanos , Ratones , Microondas , Estructura Molecular , Células 3T3 NIH , Relación Estructura-ActividadRESUMEN
BACKGROUND: Altered glutamatergic neurotransmission and neuropeptide levels play a central role in migraine pathomechanism. Previously, we confirmed that kynurenic acid, an endogenous glutamatergic antagonist, was able to decrease the expression of pituitary adenylate cyclase-activating polypeptide 1-38, a neuropeptide with known migraine-inducing properties. Hence, our aim was to reveal the role of the peripheral kynurenine pathway (KP) in episodic migraineurs. We focused on the complete tryptophan (Trp) catabolism, which comprises the serotonin and melatonin routes in addition to kynurenine metabolites. We investigated the relationship between metabolic alterations and clinical characteristics of migraine patients. METHODS: Female migraine patients aged between 25 and 50 years (n = 50) and healthy control subjects (n = 34) participated in this study. Blood samples were collected from the cubital veins of subjects (during both the interictal/ictal periods in migraineurs, n = 47/12, respectively). 12 metabolites of Trp pathway were determined by neurochemical measurements (UHPLC-MS/MS). RESULTS: Plasma concentrations of the most Trp metabolites were remarkably decreased in the interictal period of migraineurs compared to healthy control subjects, especially in the migraine without aura (MWoA) subgroup: Trp (p < 0.025), L-kynurenine (p < 0.001), kynurenic acid (p < 0.016), anthranilic acid (p < 0.007), picolinic acid (p < 0.03), 5-hydroxy-indoleaceticacid (p < 0.025) and melatonin (p < 0.023). Several metabolites showed a tendency to elevate during the ictal phase, but this was significant only in the cases of anthranilic acid, 5-hydroxy-indoleaceticacid and melatonin in MWoA patients. In the same subgroup, higher interictal kynurenic acid levels were identified in patients whose headache was severe and not related to their menstruation cycle. Negative linear correlation was detected between the interictal levels of xanthurenic acid/melatonin and attack frequency. Positive associations were found between the ictal 3-hydroxykynurenine levels and the beginning of attacks, just as between ictal picolinic acid levels and last attack before ictal sampling. CONCLUSIONS: Our results suggest that there is a widespread metabolic imbalance in migraineurs, which manifests in a completely depressed peripheral Trp catabolism during the interictal period. It might act as trigger for the migraine attack, contributing to glutamate excess induced neurotoxicity and generalised hyperexcitability. This data can draw attention to the clinical relevance of KP in migraine.
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Quinurenina , Espectrometría de Masas en Tándem , Adulto , Femenino , Humanos , Ácido Quinurénico , Persona de Mediana Edad , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , PronósticoRESUMEN
Nasal drug delivery has become a popular research field in the last years. This is not surprising since the nose possesses unique anatomical and physical properties. Via the nasal mucosa local, systemic, and directly central nerve systemic (CNS) effect is achievable. Powders have favorable physicochemical properties over liquid formulations. Lamotrigine (LAM) is an antiepileptic agent with a relatively mild side effect spectrum, but only available in tablet form on market. Reducing the particle size to the nano range can affect the bioavailability of pharmaceutical products. The aim of this article was to continue the work started, compare the in vitro properties of a nanonized lamotrigine containing nasal powder (nanoLAMpowder) and its physical mixture (PM) that were prepared by dry milling. Moreover, to study their trans-epithelial absorption to reach the blood and target the brain by axonal transport. Due to the dry milling technique, the particle size of LAM, their surface and also their structure changed that led to higher in vitro dissolution and permeability rate. The results of the in vivo tests showed that the axonal transport of the drug was assumable by both intranasal formulations because the drug was present in the brain within a really short time, but the LAM from the nanoLAMpowder liberated even faster.
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Anticonvulsivantes/administración & dosificación , Química Farmacéutica/métodos , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos/métodos , Lamotrigina/administración & dosificación , Nanopartículas/administración & dosificación , Polvos/administración & dosificación , Administración Intranasal , Animales , Anticonvulsivantes/sangre , Anticonvulsivantes/farmacocinética , Transporte Axonal , Disponibilidad Biológica , Rastreo Diferencial de Calorimetría , Cromatografía Liquida , Lamotrigina/sangre , Lamotrigina/farmacocinética , Masculino , Espectrometría de Masas , Microscopía Electrónica de Rastreo , Nanopartículas/química , Nanopartículas/ultraestructura , Cavidad Nasal , Mucosa Nasal/efectos de los fármacos , Mucosa Nasal/metabolismo , Tamaño de la Partícula , Permeabilidad , Ratas , Ratas Sprague-Dawley , SolubilidadRESUMEN
Glycerophospholipids (PLs), as amphipathic small molecules and the main constituents of biological membranes, play an important role in several cellular processes, even though their accurate identification from complex biological samples remains a challenge. In this paper, we report a fast and comprehensive HILIC-ESI-MS method for the analysis of glycerophospholipid classes using high-resolution mass spectrometry in negative mode. The final method enabled the quantitative analysis of 130 endogenous PL species in mouse plasma. The application of the method developed was to find differences of plasma PL composition in a mouse model of anxiety disorder. In the case of four PL classes and 35 PL species, significant differences were observed comparing low anxiety-related behavior with high anxiety-related behavior groups. The most characteristic trend was up-regulation in both the PL classes and PL species, and decreases were only detected in two phosphatidylcholines among 35 species in mice having elevated anxiety.
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Trastornos de Ansiedad/sangre , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Fosfolípidos/sangre , Animales , Trastornos de Ansiedad/metabolismo , Modelos Animales de Enfermedad , Interacciones Hidrofóbicas e Hidrofílicas , Masculino , Ratones , Fosfolípidos/metabolismoRESUMEN
The aim of this article was to study the trans-epithelial absorption to reach the blood and to target the brain by axonal transport using nasal formulations with nanonized meloxicam (nano MEL spray) and its salt form known as meloxicam potassium monohydrate (MELP spray). The physicochemical properties and the mucoadhesivity of nasal formulations were controlled. In vitro and in vivo studies were carried out. These forms were first investigated in "nose-to-brain" relation. It was found that the in vitro study and in vivo study did not show any significant correlation. In vitro experiments demonstrated faster dissolution rate and higher diffusion of MELP from the spray compared with the nano MEL spray. The administration of the nano MEL spray resulted in faster absorption and constant plasma concentration of the drug after five minutes of administration as compared to MELP. The axonal transport of the drug was justified. MEL appeared in the brain tissues after the first five minutes of administration in the case of both spray forms, but its amount was too small in comparison with the total plasma concentration. The application of the nano MEL spray resulted in the same AUC in the brain as the intravenous injection. The "nose-to-blood" results predicted the nasal applicability of MEL and MELP in pain management. The "nose-to-brain" pathway requires further study.
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Sistemas de Liberación de Medicamentos/métodos , Absorción Nasal , Tiazinas , Tiazoles , Administración Intranasal , Animales , Sistemas de Liberación de Medicamentos/instrumentación , Masculino , Meloxicam , Ratas , Ratas Sprague-Dawley , Tiazinas/química , Tiazinas/farmacocinética , Tiazinas/farmacología , Tiazoles/química , Tiazoles/farmacocinética , Tiazoles/farmacologíaRESUMEN
BACKGROUND: Diabetes mellitus is a chronic metabolic disorder which induces endothelial dysfunction and platelet activation. Eicosanoids produced from arachidonic acid regulate cellular and vascular functions. Sigma-1 receptors (S1R) are expressed in platelets and endothelial cells and S1R expression is protective in diabetes. OBJECTIVES: Our aim was to examine the influence of sub-chronic, in vivo administered S1R ligands PRE-084, (S)-L1 (a new compound) and NE-100 on the ex vivo arachidonic acid metabolism of platelets and aorta in streptozotocin-induced diabetic rats. METHODS: The serum level of the S1R ligands was detected by LC-MS/MS before the ex vivo analysis. Sigma-1 receptor and cyclooxygenase gene expression in platelets were determined by RT-qPCR. The eicosanoid synthesis was examined with a radiolabelled arachidonic acid substrate and ELISA. RESULTS: One month after the onset of STZ-induced diabetes, in vehicle-treated, diabetic rat platelet TxB2 and aortic 6-k-PGF1α production dropped. Sub-chronic in vivo treatment of STZ-induced diabetes in rats for one week with PRE-084 enhanced vasoconstrictor and platelet aggregator and reduced vasodilator and anti-aggregator cyclooxygenase product formation. (S)-L1 reduced the synthesis of vasodilator and anti-aggregator cyclooxygenase metabolites and promoted the recovery of physiological platelet function in diabetic rats. The S1R antagonist NE-100 produced no significant changes in platelet arachidonic acid metabolism. (S)-L1 decreased the synthesis of vasoconstrictor and platelet aggregator cyclooxygenase metabolites, whereas NE-100 increased the quantity of aortic vasodilator and anti-aggregator cyclooxygenase products and promoted the recovery of diabetic endothelial dysfunction in the aorta. The novel S1R ligand, (S)-L1 had similar effects on eicosanoid synthesis in platelets as the agonist PRE-084 and in aortas as the antagonist NE-100. CONCLUSIONS: S1R ligands regulate cellular functions and local blood circulation by influencing arachidonic acid metabolism. In diabetes mellitus, the cell-specific effects of S1R ligands have a compensatory role and aid in restoring physiological balance between the platelet and vessel.
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Diabetes Mellitus Experimental , Animales , Ratas , Estreptozocina , Ácido Araquidónico/farmacología , Diabetes Mellitus Experimental/metabolismo , Ligandos , Células Endoteliales/metabolismo , Cromatografía Liquida , Espectrometría de Masas en Tándem , Ácidos Araquidónicos/metabolismo , Aorta/metabolismo , Eicosanoides , Ciclooxigenasa 2 , Vasodilatadores , Vasoconstrictores , Receptor Sigma-1RESUMEN
Platelets regulate cell-cell interactions and local circulation through eicosanoids from arachidonic acid. Sigma non-opioid intracellular receptor 1 (sigma-1 receptor) expressed in platelets and endothelial cells can regulate intracellular signalization. Our aim was to examine the influence of sub-chronic, in vivo-administered sigma-1 receptor ligands 2-morpholin-4-ylethyl 1-phenylcyclohexane-1-carboxylate (PRE-084); N-benzyl-2-[(1S)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolin-1-yl]ethan-1-amine; dihydrochloride, a new compound ((S)-L1); and N-[2-[4-methoxy-3-(2-phenylethoxy)phenyl]ethyl]-N-propylpropan-1-amine (NE-100) on the ex vivo arachidonic acid metabolism of the platelets and aorta of male rats. The serum level of sigma-1 receptor ligands was determined by liquid chromatography-mass spectrometry. Sigma-1 receptor and cyclooxygenase gene expression in the platelets were determined by a reverse transcription-coupled quantitative polymerase chain reaction. The eicosanoid synthesis was examined using a radiolabeled arachidonic acid substrate and enzyme-linked immunosorbent assay. We confirmed the absorption of sigma-1 receptor ligands and confirmed that the ligands were not present during the ex vivo studies, so their acute effect could be excluded. We detected no changes in either sigma-1 receptor or cyclooxygenase mRNA levels in the platelets. Nevertheless, (S)-L1 and NE-100 increased the quantity of cyclooxygenases there. Both platelet and aortic eicosanoid synthesis was modified by the ligands, although in different ways. The effect of the new sigma-1 receptor ligand, (S)-L1, was similar to that of PRE-084 in most of the parameters studied but was found to be more potent. Our results suggest that sigma-1 receptor ligands may act at multiple points in arachidonic acid metabolism and play an important role in the control of the microcirculation by modulating the eicosanoid synthesis of the platelets and vessels.
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Plaquetas , Receptores sigma , Animales , Aorta/metabolismo , Ácidos Araquidónicos/metabolismo , Ciclooxigenasa 2/metabolismo , Eicosanoides/metabolismo , Células Endoteliales/metabolismo , Ligandos , Masculino , Ratas , Receptores sigma/metabolismoRESUMEN
BACKGROUND: Biomarkers for predicting treatment response to thrombolysis in acute ischemic stroke are currently lacking. Both, animal models and clinical studies have provided evidence that the kynurenine (KYN) pathway is activated in ischemic stroke. OBJECTIVES: In our pilot study, we aimed to investigate whether KYN pathway enzymes and metabolites could serve as potential biomarkers for treatment response in the hyperacute phase of ischemic stroke. MATERIAL AND METHODS: We included 48 acute ischemic stroke patients who received thrombolysis. Blood samples were taken both before and 12 h after treatment. Concentrations of 11 KYN metabolites were determined using ultra-high-performance liquid chromatography-mass spectrometry. To assess the treatment response, we used early neurological improvement (ENI), calculated as the difference between the admission and discharge National Institutes of Health Stroke Scale (NIHSS) scores. We performed receiver operating characteristic (ROC) analysis for KYN pathway metabolites and enzymes that showed a correlation with ENI. RESULTS: In the samples taken before thrombolysis, significantly lower concentrations of kynurenic acid (KYNA) and kynurenine aminotransferase (KAT) activity were found in patients who had ENI (p = 0.01 and p = 0.002, respectively). According to the ROC analysis, the optimal cut-off value to predict ENI for KYNA was 37.80 nM (sensitivity (SN) 69.2%, specificity (SP) 68.4%) and 0.0127 for KAT activity (SN 92.3%, SP 73.7%). CONCLUSIONS: Our research is the first clinical pilot study to analyze changes in the KYN pathway in ischemic stroke patients who received thrombolytic treatment. Based on our results, baseline KYNA concentration and KAT activity could serve as potential biomarkers to predict early treatment response to thrombolysis.
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Isquemia Encefálica , Ácido Quinurénico/sangre , Accidente Cerebrovascular , Terapia Trombolítica , Transaminasas/sangre , Biomarcadores/sangre , Isquemia Encefálica/tratamiento farmacológico , Humanos , Proyectos Piloto , Accidente Cerebrovascular/tratamiento farmacológico , Estados UnidosRESUMEN
Aims: Neutrophil granulocytes are the major cells involved in Chlamydia trachomatis (C. trachomatis)-mediated inflammation and histopathology. A key protein in human intracellular antichlamydial defense is the tryptophan-degrading enzyme indoleamine 2,3-dioxygenase (IDO) which limits the growth of the tryptophan auxotroph Chlamydia. Despite its importance, the role of IDO in the intracellular defense against Chlamydia in neutrophils is not well characterized. Methods: Global gene expression screen was used to evaluate the effect of C. trachomatis serovar D infection on the transcriptome of human neutrophil granulocytes. Tryptophan metabolite concentrations in the Chlamydia-infected and/or interferon-gamma (IFNG)-treated neutrophils were measured by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Results: Our results indicate that the C. trachomatis infection had a major impact on neutrophil gene expression, inducing 1,295 genes and repressing 1,510 genes. A bioinformatics analysis revealed that important factors involved in the induction of neutrophil gene expression were the interferon-related transcription factors such as IRF1-5, IRF7-9, STAT2, ICSB, and ISGF3. One of the upregulated genes was ido1, a known infection- and interferon-induced host gene. The tryptophan-degrading activity of IDO1 was not induced significantly by Chlamydia infection alone, but the addition of IFNG greatly increased its activity. Despite the significant IDO activity in IFNG-treated cells, C. trachomatis growth was not affected by IFNG. This result was in contrast to what we observed in HeLa human cervical epithelial cells, where the IFNG-mediated inhibition of C. trachomatis growth was significant and the IFNG-induced IDO activity correlated with growth inhibition. Conclusions: IDO activity was not able to inhibit chlamydial growth in human neutrophils. Whether the IDO activity was not high enough for inhibition or other chlamydial growth-promoting host mechanisms were induced in the infected and interferon-treated neutrophils needs to be further investigated.
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Infecciones por Chlamydia/microbiología , Chlamydia trachomatis/crecimiento & desarrollo , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Neutrófilos/enzimología , Triptófano/metabolismo , Infecciones por Chlamydia/enzimología , Infecciones por Chlamydia/inmunología , Chlamydia trachomatis/inmunología , Chlamydia trachomatis/metabolismo , Células HL-60 , Células HeLa , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Interferón gamma/farmacología , Metaboloma , Neutrófilos/efectos de los fármacos , TranscriptomaRESUMEN
The simultaneous quantitative estimation of tryptophan (TRP) and its metabolites represents a great challenge because of their diverse chemical properties, e.g., presence of acidic, basic, and nonpolar functional groups and their immensely different concentrations in biological matrices. A short ultra high-performance liquid chromatography (UHPLC)-tandem mass spectrometry (MS/MS) method was validated for targeted analysis of TRP and its 11 most important metabolites derived via both kynurenine (KYN) and serotonin (SERO) pathways in human serum and cerebrospinal fluid (CSF): SERO, KYN, 3-hydroxyanthranilic acid, 5-hydroxyindoleacetic acid, anthranilic acid, kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK), xanthurenic acid, melatonin, picolinic acid (PICA), and quinolinic acid (QUIN). After selecting the "best" reversed-phase column and organic modifier, DryLab®4 was used to optimize the gradient time and temperature in chromatographic separation. To achieve absolute quantification, deuterium-labeled internal standards were used. Among all compounds, 3 were analyzed in derivatized (butyl ester) forms (3-HK, PICA, and QUIN) and the remaining 9 in underivatized forms. Validation was performed in accordance with the ICH and FDA guidelines to determine the intraday and interday precision, accuracy, sensitivity, and recovery. To demonstrate the applicability of the developed UHPLC-MS/MS method, the aforementioned metabolites were analyzed in serum and CSF samples from patients with multiple sclerosis (multiple sclerosis group) and those with symptomatic or noninflammatory neurological diseases (control group). The concentration of QUIN dramatically increased, whereas that of KYNA slightly decreased in the multiple sclerosis group, resulting in a significantly increased QUIN/KYNA ratio and significantly decreased PICA/QUIN ratio.
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Esclerosis Múltiple Recurrente-Remitente/diagnóstico , Espectrometría de Masas en Tándem/métodos , Triptófano/análisis , Adulto , Biomarcadores/análisis , Biomarcadores/metabolismo , Calibración , Estudios de Casos y Controles , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Líquida de Alta Presión/normas , Femenino , Humanos , Ácido Quinurénico/análisis , Ácido Quinurénico/metabolismo , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/sangre , Esclerosis Múltiple Recurrente-Remitente/líquido cefalorraquídeo , Ácidos Picolínicos/análisis , Ácidos Picolínicos/metabolismo , Ácido Quinolínico/análisis , Ácido Quinolínico/metabolismo , Estándares de Referencia , Espectrometría de Masas en Tándem/instrumentación , Espectrometría de Masas en Tándem/normas , Triptófano/metabolismo , Adulto JovenRESUMEN
The aim of this study was to optimize the formulation of meloxicam (MEL)-containing human serum albumin (HSA) nanoparticles for nose-to-brain via a quality by design (QbD) approach. Liquid and dried formulations of nanoparticles containing Tween 80 and without the surfactant were investigated. Various properties, such as the Z-average, zeta potential, encapsulation efficacy (EE), conjugation of MEL and HSA, physical stability, in vitro dissolution, in vitro permeability, and in vivo plasma and brain distribution of MEL were characterized. From a stability point of view, a solid product (Mel-HSA-Tween) is recommended for further development since it met the desired critical parameters (176 ± 0.3 nm Z-average, 0.205 ± 0.01 PdI, -14.1 ± 0.7 mV zeta potential) after 6 months of storage. In vitro examination showed a significantly increased drug dissolution and permeability of MEL-containing nanoparticles, especially in the case of applying Tween 80. The in vivo studies confirmed both the trans-epithelial and axonal transport of nanoparticles, and a significantly higher cerebral concentration of MEL was detected with nose-to-brain delivery, in comparison with intravenous or per os administration. These results indicate intranasal the administration of optimized MEL-containing HSA formulations as a potentially applicable "value-added" product for the treatment of neuroinflammation.
RESUMEN
The unique requirements of poorly water-soluble drug delivery have driven a great deal of research into new formulations and routes of administration. This study investigates the use of nanosuspensions for solubility enhancement and drug delivery. Simple methods were used to prepare nasal formulations of loratadine based on nanosuspension pre-dispersion with sodium hyaluronate as a mucoadhesive agent. The nanosuspension was prepared by antisolvent precipitation method followed by ultrasonication and characterized for particle size, polydispersity index, zeta potential, morphology, and structure. Moreover, the nasal formulations were characterized for drug loading, pH, particle size, viscosity, bioadhesive viscosity parameter, and were evaluated for in vitro dissolution and diffusion, in addition to in vivo studies in a rat model. Loratadine nanosuspension displayed a particle size of 311 nm, a polydispersity index of 0.16, and zeta potential of -22.05 mV. The nanosuspension preserved the crystalline status of the raw drug. The addition of sodium hyaluronate exhibited an increase in the mean particle size and zeta potential of the nanoparticles. The nasal formulations showed enhanced bioadhesive properties compared to the unprocessed loratadine in the reference samples. The nanosuspension based-formulation that contained 5 mg mL-1 sodium hyaluronate and 2.5 mg mL-1 loratadine (NF4) showed a significant enhancement of flux and permeability coefficient through a synthetic membrane. NF4 exhibited 24.73 µg cm-2 h-1 and 0.082 cm h-1, while the reference sample showed 1.49 µg cm-2 h-1 and 0.017 cm h-1, for the flux and the permeability coefficient, respectively. Nasal administration of NF4 showed a bioavailability of 5.54-fold relative to the oral administration. The results obtained in this study indicate the potential of the nasal route and the nanosuspension for loratadine delivery. The relative bioavailability of NF4 was 1.84-fold compared to unprocessed loratadine in the reference sample. Therefore, the nanosized loratadine could be suggested as a practical and simple nanosystem for the intranasal delivery with improved bioavailability.
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Adhesivos/química , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos/métodos , Ácido Hialurónico/química , Loratadina/química , Loratadina/farmacocinética , Nanoestructuras/química , Suspensiones/química , Adhesivos/administración & dosificación , Administración Intranasal , Administración Oral , Animales , Disponibilidad Biológica , Liberación de Fármacos , Ácido Hialurónico/administración & dosificación , Masculino , Nanoestructuras/administración & dosificación , Nanoestructuras/ultraestructura , Tamaño de la Partícula , Ratas , Propiedades de Superficie , Suspensiones/administración & dosificación , ViscosidadRESUMEN
PURPOSE: The aim of this work was to study the influence of solidification of meloxicam (Mel) containing nanosuspension (nanoMel) on the physical stability and drug bioavailability of the products. The nanoMel sample had poly(vinyl alcohol) (PVA) as a protective polymer, but no surfactant as a further stabilizing agent because the final aim was to produce surfactant-free solid phase products as well. METHODS: The solidified samples produced by fluidization and lyophilization (fluidMel, lyoMel) were examined for particle size, crystallinity, and in vitro release of Mel compared to similar parameters of nanoMel. The products were subjected to an animal experiment using per oral administration to verify their bioavailability. RESULTS: Mel containing (1%) nanoMel sample was produced by wet milling process using an optimized amount of PVA (0.5%) which resulted in 130 nm as mean particle size and a significant reduction in the degree of crystallinity (13.43%) of Mel. The fluidization technique using microcrystalline cellulose (MCC) as carrier resulted in a quick conversion and no significant change in the critical product parameters. The process of lyophilization required a longer operation time, which resulted in the amorphization of the crystalline carrier (trehalose) and the recrystallization of Mel increased its particle size and crystallinity. The fluidMel and lyoMel samples had nearly five-fold higher relative bioavailability than nanoMel application by oral administration. The correlation between in vitro and in vivo studies showed that the fixed Mel nanoparticles on the surface of solid carriers (MCC, trehalose) in both the artificial gastric juice and the stomach of the animals rapidly reached saturation concentration leading to faster dissolution and rapid absorption. CONCLUSION: The solidification of the nanosuspension not only increased the stability of the Mel nanoparticles but also allowed the preparation of surfactant-free compositions with excellent bioavailability which may be an important consideration for certain groups of patients to achieve rapid analgesia.
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Analgesia , Antiinflamatorios no Esteroideos/uso terapéutico , Inhibidores de la Ciclooxigenasa 2/uso terapéutico , Meloxicam/uso terapéutico , Nanopartículas/química , Dolor/tratamiento farmacológico , Administración Oral , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/química , Disponibilidad Biológica , Inhibidores de la Ciclooxigenasa 2/administración & dosificación , Inhibidores de la Ciclooxigenasa 2/química , Liberación de Fármacos , Estabilidad de Medicamentos , Humanos , Meloxicam/administración & dosificación , Meloxicam/química , Tamaño de la Partícula , Alcohol Polivinílico/química , Propiedades de Superficie , Suspensiones/químicaRESUMEN
A novel online system including two-dimensional liquid chromatography coupled to high-resolution mass spectrometry (2D-LC/MS) was developed and applied for comprehensive phospholipid (PL) and sphingomyelin (SM) profiling of dorsal hippocampus (DHPC), ventral (VHPC) and prefrontal cortex (PFC) brain regions in a mouse model of anxiety disorder. In the first dimension, lipid classes were distinguished by hydrophilic interaction liquid chromatography (HILIC), while the second dimensional separation of individual PL and SM species was achieved by reversed-phase (RP) chromatography. For the enrichment of lipid species in diluted HILIC effluent, two RP trapping columns were used separately. The developed fully-automated 2D method allowed the quantitative analysis of over 150 endogenous PL and SM species in mouse brain regions within 40min. The developed method was applied in a pilot study, which aimed to find alteration of PL and SM composition in a mouse model of anxiety disorder. In the case of 37 PL and SM species, significant differences were observed between high anxiety-related behavior (AX) and low anxiety-related behavior (nAX) mice. In mice having elevated anxiety, the most typical trend was the downregulation of PL species, in particular, in VHPC.