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1.
BMC Public Health ; 23(1): 2162, 2023 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-37926849

RESUMEN

BACKGROUND: Depression is increasingly recognized as a worldwide serious, public health concern. A better understanding of depression is important for advancing its management and learning the difference between major depressive disorder (MDD) and dysthymia. Our aim is to conduct a concurrent analysis of the trends of both MDD and dysthymia in China. METHODS: The data on depression from 1990 to 2019 were collected from the Global Burden of Disease Study 2019 (GBD 2019). To determine the average annual percent changes (AAPC) and relative risks (RRs), joinpoint regression and the age-period-cohort models were employed, respectively. RESULTS: The incidence number of MDD and dysthymia continuously increased in China from 1990 to 2019, however, the age-standardized rates (ASR) had a decreasing trend in both men and women. The results from joinpoint regression showed that a declining trend was presented in young people (< 50 years) but an increased trend in the elderly (≥ 50 years) both in men and women, during 1990-2019. Age is the most influential factor for MDD and dysthymia. Age RRs for MDD incidence had an overall increasing trend with age. Period RR in MDD presented a U-shaped pattern, while Cohort RRs presented an inverted U-shaped pattern. On the other hand, RRs in dysthymia for period and cohort effects had no statistical significance, only the age effect presented an inverted U-shaped pattern. CONCLUSIONS: The disparities in trends observed between MDD and dysthymia during the period of 1990-2019 indicated the significance of distinguishing between these two disorders. The age, period and cohort effects all had a greater impact on MDD than on dysthymia, and age effects presented different influential patterns in these two. To alleviate the burden of depressive disorders in China, proactive measures need to be implemented, with particular attention to the elderly population.


Asunto(s)
Trastorno Depresivo Mayor , Masculino , Humanos , Femenino , Anciano , Adolescente , Trastorno Depresivo Mayor/epidemiología , Trastorno Distímico/epidemiología , Incidencia , China/epidemiología , Efecto de Cohortes
2.
Drug Deliv ; 23(6): 1868-81, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25544601

RESUMEN

Coenzyme Q10 (CoQ10), also known as ubiquinone or ubidecarenone, is a powerful, endogenously produced, intracellularly existing lipophilic antioxidant. It combats reactive oxygen species (ROS) known to be responsible for a variety of human pathological conditions. Its target site is the inner mitochondrial membrane (IMM) of each cell. In case of deficiency and/or aging, CoQ10 oral supplementation is warranted. However, CoQ10 has low oral bioavailability due to its lipophilic nature, large molecular weight, regional differences in its gastrointestinal permeability and involvement of multitransporters. Intracellular delivery and mitochondrial target ability issues pose additional hurdles. To maximize CoQ10 delivery to its biopharmaceutical target, numerous approaches have been undertaken. The review summaries the current research on CoQ10 bioavailability and highlights the headways to obtain a satisfactory intracellular and targeted mitochondrial delivery. Unresolved questions and research gaps were identified to bring this promising natural product to the forefront of therapeutic agents for treatment of different pathologies.


Asunto(s)
Antioxidantes/administración & dosificación , Mitocondrias/química , Ubiquinona/análogos & derivados , Ubiquinona/administración & dosificación , Administración Oral , Antioxidantes/química , Disponibilidad Biológica , Humanos , Especies Reactivas de Oxígeno/metabolismo , Ubiquinona/química
3.
Saudi Pharm J ; 22(5): 419-28, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25473330

RESUMEN

OBJECTIVE: Medication use during pregnancy is a major concern for most women. The aim of the present study was to assess medication use, knowledge and beliefs about medications among pregnant women in Saudi Arabia. METHODS: More than 760 pregnant women, attending the obstetric clinic, filled a semi-structured questionnaire. Data were collected about their sociodemographic background, medication use during pregnancy, medication/pregnancy risk awareness, sources of drug information and beliefs about medications. RESULTS: Most women had a positive attitude toward medications in general but they believed pregnant women should be more cautious regarding drug-use during pregnancy. A significant association was found between participants' education and occupation, and beliefs about medications. In this context, well educated women and those working in a health-related career demonstrated more correct beliefs about medications. Women with health-related occupations were more knowledgeable about the life saving effect of drugs on unborn children. Women indicated inadequate provision of drug-related information from physician and pharmacist; they rely on medication pamphlet to get such information. The most frequently used drugs were paracetamol and vitamins (13.2%). Most pregnant women (59.2%) were able to identify drugs to-be avoided in pregnancy that agreed roughly with FDA categories with 23 hits out of 32. They indicated that newborn anomalies (6.5%) were not attributed to drug-use during pregnancy. CONCLUSION: During pregnancy, women were more conservative and skeptic toward medication, health-care professionals should be aware of such attitudes when advising pregnant women to take medication.

4.
J Microencapsul ; 31(7): 674-84, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24963960

RESUMEN

AIM: To study the effect of poly(d,l-lactic-co-glycolic acid) (PLGA) microparticles (MPs) preparation techniques on particle physical characterization with special emphasis on burst drug release. METHODS: A basic drug clozapine was used in combination with acid-terminated PLGA. Two approaches for MP preparation were compared; the in situ forming microparticle (ISM) and the emulsion-solvent evaporation (ESE) methods using an experimental design. The MPs obtained were compared according to their physical characterization, burst release and T80%. An in vivo pharmacokinetic study with in vitro-in vivo correlation (IVIVC) was also performed for the selected formula. RESULTS: Both methods were able to sustain drug release for three weeks. ISM produced more porous particles and was not effective as ESE for controlling burst release. A good IVIVC (R(2) = 0.9755) was attained when injecting the selected formula into rats. CONCLUSION: MPs prepared with ESE showed a minimum burst release and a level A IVIVC was obtained when administered to rats.


Asunto(s)
Antipsicóticos , Clozapina , Ácido Láctico , Ácido Poliglicólico , Animales , Antipsicóticos/química , Antipsicóticos/farmacocinética , Antipsicóticos/farmacología , Clozapina/química , Clozapina/farmacocinética , Clozapina/farmacología , Preparaciones de Acción Retardada , Ácido Láctico/química , Ácido Láctico/farmacocinética , Ácido Láctico/farmacología , Masculino , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacocinética , Ácido Poliglicólico/farmacología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas
5.
Drug Deliv ; 21(4): 265-75, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24093513

RESUMEN

The aim of this was to investigate and compare the chemosensitizing effect of some pharmaceutical excipients (TPGS, Pluronic P85 and chitosan) by evaluating the cytotoxicity of the chemotherapeutic drug Hydroxy Camptothecin (HCPT) loaded into PLGA nanoparticles. Different nanoparticles formulations were developed and evaluated for size, zeta potential, morphology, loading and encapsulation efficiency as well as in vitro drug release. The cytotoxicity of the nanoparticles was evaluated by MTT assay in A549 (human lung carcinoma cell line) and HT29 (human colon carcinoma cell line) whereas their cellular uptake was determined by confocal laser scanning microscopy and microfluorimetry assay. The results revealed that nanoparticles possessed a desirable nanometric size (revealed by dynamic light scattering measurements and TEM) with appreciable HCPT encapsulation (>48%) and negative surface charge that was switched to positive upon coating with chitosan. The nanoparticles adopted a sustained release phase preceded by initial burst of HCPT that was reduced by chitosan coating. The cytotoxicity of the nanoparticles in A549 and HT29 cells was significantly augmented compared to simple drug solution and basic nanoparticles without excipients. The excipients could be ranked according to their IC50 lowering effect in the following order [TPGS (sixfold lower IC50) > Pluronic P85 > Chitosan]. The augmented cytotoxicity and chemosensitizing effect might be attributed to overcoming drug efflux (in case of TPGS 1000 or Pluronic P85) and/or maximizing internalization by cancer cells (chitosan coating). Acting as chemopotentiators, the studied excipients could have potential in reducing therapeutic HCPT doses and minimizing adverse effects in lung and colon chemotherapy.


Asunto(s)
Camptotecina/análogos & derivados , Neoplasias del Colon , Citotoxinas/química , Excipientes/química , Neoplasias Pulmonares , Nanopartículas/química , Camptotecina/química , Camptotecina/farmacocinética , Camptotecina/toxicidad , Línea Celular Tumoral , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/metabolismo , Citotoxinas/farmacocinética , Citotoxinas/toxicidad , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidad , Excipientes/farmacocinética , Excipientes/toxicidad , Células HT29 , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Nanopartículas/toxicidad
6.
Eur J Pharm Sci ; 51: 59-66, 2014 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-23999035

RESUMEN

Chitosan microspheres are potential drug carriers for maximizing nasal residence time, circumventing rapid mucociliary clearance and enhancing nasal absorption. The aim of the present study was to develop and characterize chitosan mucoadhesive microspheres of verapamil hydrochloride (VRP) for intranasal delivery as an alternative to oral VRP which suffers low bioavailability (20%) due to extensive first pass effect. The microspheres were produced using a spray-drying and precipitation techniques and characterized for morphology (scanning electron microscopy), particle size (laser diffraction method), drug entrapment efficiency, thermal behavior (differential scanning calorimetry) and crystallinity (X-ray diffractometric studies) as well as in vitro drug release. Bioavailability of nasal VRP microspheres was studied in rabbits and the results were compared to those obtained after nasal, oral and intravenous administration of VRP solution. Results demonstrated that the microspheres were spherical with size 21-53 µm suitable for nasal deposition. The spray-drying technique was superior over precipitation technique in providing higher VRP entrapment efficiency and smaller burst release followed by a more sustained one over 6h. The bioavailability study demonstrated that the nasal microspheres exhibited a significantly higher bioavailability (58.6%) than nasal solution of VRP (47.8%) and oral VRP solution (13%). In conclusion, the chitosan-based nasal VRP microspheres are promising for enhancing VRP bioavailability by increasing the nasal residence time and avoiding the first-pass metabolism of the drug substance.


Asunto(s)
Quitosano/química , Verapamilo/administración & dosificación , Verapamilo/farmacocinética , Adhesividad , Administración Intranasal , Animales , Disponibilidad Biológica , Masculino , Microesferas , Mucosa Nasal/metabolismo , Tamaño de la Partícula , Conejos , Verapamilo/química
7.
Saudi Pharm J ; 22(6): 528-36, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25561865

RESUMEN

INTRODUCTION: Drug promotion has to contribute to a more rational use of drugs. Concerns arise if promotion negatively influences prescribing/dispensing pattern. It is warranted to assess exposure and attitudes to, and acceptance of, drug promotion among pharmacists and physicians. METHODOLOGY: Adopting a randomized, multiple site and cross-sectional survey study, questionnaires (n = 250) were completed by physicians and pharmacists to investigate the exposure, acceptance or skepticism of Saudi physicians/pharmacists to drug promotion as well as their perception of the appropriateness of gifts and to check if they had any teaching/training about dealing with medical representatives (MRs) and Pharma promotion. RESULTS: Significantly more pharmacists than physicians (32% vs. 23%; p < 0.05) reported being taught or educated about the ethics of drug promotion. The experience level was significantly associated with the teaching or training that the physicians and pharmacists received. Conference registration fees and drug samples were the most appropriate promotional gift for the physicians (67% and 66%, respectively; p < 0.01) whereas for pharmacists, the drug sample was considered the most suitable donation (79%). More pharmacists perceived drug companies as a useful way to gain knowledge about drugs than physicians (75% vs. 65%; p < 0.01). A higher proportion of both groups were accepting drug promotion than those skeptical about it. CONCLUSION: The majority of physicians or pharmacists participating in this study have received gifts from pharmaceutical companies. The drug samples and printed educational materials are the most widely accepted gifts. Recent graduates and those with few years of experience had higher teaching/training than experienced physicians and pharmacists in pharmaceutical promotion ethics and tactics to deal with MRs. On the other hand, experienced healthcare team were more approached and targeted by pharmaceutical companies and MRs. It is highly recommended to implement courses/discussion groups on the ethical interaction between healthcare professionals and pharmaceutical companies in the curriculum of both pharmacy and medicine. Updating the physicians and pharmacists after graduation, as part of continued medical/pharmacy education, will eventually improve the healthcare professionals' capability to act to the patients' welfare.

8.
Carbohydr Polym ; 94(1): 669-76, 2013 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23544589

RESUMEN

Engineering polymer surfaces reduces nanoparticles (NPs) aggregation and phagocytosis due to effective shielding, hindering recognition by the reticuloendothelial system (RES). The shielding of NPs is complex and affected by the type of groups used in terms of charge and hydrophilicity. This will, in turn, affect NPs biodistribution which will determine the length of activity of the drug. Polysaccharides are nowadays recognized for decreasing the uptake of particulate carriers by the mononuclear phagocytic system (MPS). Chitosan is considered as an attractive candidate due to its biocompatibility, biodegradability, non-toxicity and low cost. In this study clozapine (CZP)-loaded NPs were coated with chitosan, pluronic F-68, polyethylene glycol (PEG) 4000 and polysorbate 80. The factors affecting drug encapsulation efficiency, particle size, surface charge, surface hydrophilicity, pharmacokinetics and biodistribution were studied. The results proved that although a similarity in surface hydrophilicity, chitosan-stealth NPs showed different pharmacokinetic profile and biodistribution behavior compared to polysorbate-stealth NPs.


Asunto(s)
Antipsicóticos/farmacocinética , Quitosano/química , Clozapina/farmacocinética , Nanocápsulas/química , Adsorción , Animales , Antipsicóticos/administración & dosificación , Antipsicóticos/química , Análisis Químico de la Sangre/normas , Clozapina/administración & dosificación , Clozapina/química , Composición de Medicamentos , Interacciones Hidrofóbicas e Hidrofílicas , Masculino , Ratones , Tamaño de la Partícula , Poloxámero/química , Polietilenglicoles/química , Polisorbatos/química , Ratas , Estándares de Referencia , Esterilización , Propiedades de Superficie , Distribución Tisular
9.
Probiotics Antimicrob Proteins ; 5(3): 216-26, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26782990

RESUMEN

The wide spread of antimicrobial resistance has urged the need of alternative therapeutic approach. In this context, probiotic lactobacilli have been reported for the prevention and treatment of many gastrointestinal and urogenital infections. However, very little is known about their antagonistic activity against skin pathogens. Accordingly, the present study aimed to investigate the potential of lactobacilli to interfere with pathogenesis features of two antibiotic-resistant skin pathogens, namely methicillin-resistant Staphylococcus aureus and multiple-resistant Pseudomonas aeruginosa. A total of 49 lactobacilli were recovered, identified and tested for their antagonistic activities against the aforementioned pathogens. Of these, eight isolates were capable of blocking the adherence of pathogens to mammalian cells independent of the skin pathogen tested or model adopted. Moreover, three Lactobacillus isolates (LRA4, LC2 and LR5) effectively prevented the pathogen internalization into epithelial cells in addition to potentiating phagocyte-mediated pathogen killing. Interestingly, the lactobacilli LC2, LF9 and LRA4 markedly inhibited the growth of P. aeruginosa and S. aureus isolates in coculture experiments. Besides, the lactobacilli LRA4, LC2, LR5 and LF9 have counteracted pathogen cytotoxicity. Taken together, the present study revealed some inhibitory activities of lactobacilli against two antibiotic-resistant skin pathogens. Moreover, it revealed two lactobacilli, namely LC2 and LRA4, with antagonistic capacity against different virulence determinants of skin pathogens. These lactobacilli are considered promising probiotic candidates that may represent an alternative therapeutic approach for skin infections.

10.
Langmuir ; 28(31): 11490-501, 2012 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-22746328

RESUMEN

Titania (anatase) nanoparticles were successfully PEGylated through the use of catechol (dopamine)-terminated PEG derivatives. The resulting materials were characterized by excellent stability at neutral pH and extremely low toxicity (phagocytic and nonphagocytic cell lines). In particular, we focused on the comparison between mono- and bis-catechol PEGs. Due to the double terminal anchorage on the titania surface, bis-catechol ligands can produce chains differing from classical monoanchored PEG in conformation (horseshoe-shaped vs brush) and thus the possibility of interactions with biomolecules. At the same time, less than quantitative catechol binding may lead to the presence of dangling chains with unbound catechols which can polymerize and eventually produce PEG/titania nanocomposite colloids. Our results on double-functional PEG2000 show the latter to be the case. Pluronic F127 was also used as a bifunctional ligand, leading to nanocomposite aggregates with an even larger organic content.


Asunto(s)
Catecoles/química , Nanocompuestos/química , Nanopartículas/química , Poloxámero/química , Polietilenglicoles/química , Titanio/química , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Coloides , Fibroblastos/efectos de los fármacos , Concentración de Iones de Hidrógeno , Ligandos , Ratones , Microscopía de Fuerza Atómica , Conformación Molecular , Nanocompuestos/toxicidad , Nanocompuestos/ultraestructura , Nanopartículas/toxicidad , Nanopartículas/ultraestructura , Fagocitos/efectos de los fármacos , Espectroscopía de Fotoelectrones , Termogravimetría , Titanio/farmacología
11.
AAPS PharmSciTech ; 13(2): 411-21, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22359159

RESUMEN

The aim of the present study was to utilize chitosan (CS) nanoparticles for the intracellular delivery of the poorly cell-penetrating antibiotic, ceftriaxone sodium (CTX). In vitro characterization of (CTX-CS) nanoparticles was conducted leading to an optimized formula that was assessed for its biocompatibility to blood (hemolysis test) and cells (MTT assay). Progressively, confocal laser scanning microscopy (CLSM), cellular uptake (microfluorimetry), and antibacterial activity of the nanoparticles were investigated in two cell lines: Caco-2 and macrophages J774.2 pre-infected with Salmonella typhimurium. Results showed that the optimized formula had size 210 nm, positive zeta potential (+30 mV) and appreciable entrapment efficiency for CTX (45%) and included a biphasic release pattern. The nanoparticles were biocompatible and were internalized by cells as verified by CLSM whereas microfluorimetry indicated substantial cellular uptake. Moreover, the CTX-chitosan nanoparticles showed a significant reduction in the count of intracellular S. typhimurium in Caco-2 and macrophages J774.2. This reduction was significantly higher than that obtained in case of placebo nanoparticles, CTX, and CTX-chitosan solutions and might be attributed to enhanced endocytic uptake of the nanoaprticles and antibacterial effect of the chitosan polymer. In conclusion, the results provide evidence for the potential use of chitosan nanoparticles to enhance the intracellular delivery and antibacterial effect of CTX in enterocytes and macrophages.


Asunto(s)
Antibacterianos/farmacología , Ceftriaxona/farmacología , Quitosano/química , Portadores de Fármacos , Mucosa Intestinal/microbiología , Macrófagos/microbiología , Nanopartículas , Salmonella typhimurium/efectos de los fármacos , Animales , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/toxicidad , Transporte Biológico , Células CACO-2 , Ceftriaxona/química , Ceftriaxona/metabolismo , Ceftriaxona/toxicidad , Supervivencia Celular/efectos de los fármacos , Química Farmacéutica , Quitosano/toxicidad , Citofotometría , Relación Dosis-Respuesta a Droga , Hemólisis/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Microscopía Confocal , Nanotecnología , Tamaño de la Partícula , Permeabilidad , Salmonella typhimurium/crecimiento & desarrollo , Solubilidad , Tecnología Farmacéutica/métodos
12.
Macromol Biosci ; 11(12): 1747-60, 2011 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-21954171

RESUMEN

The cellular uptake of hyaluronic-acid-coated, negatively charged chitosan/triphosphate nanoparticles and that of uncoated, positively charged ones is investigated by studying cellular localization, uptake kinetics and mechanism of internalization in J774.2 macrophages, using non-phagocytic L929 fibroblasts as a control for uncoated nanoparticles. Both kinds of nanoparticles undergo endosomal escape and adopt a similar clathrin-based endocytic mechanism. The surface decoration with HA profoundly influences the kinetics of cellular uptake, with an at least two orders of magnitude slower kinetics, but also the nature of the binding on the cellular surface.


Asunto(s)
Quitosano/química , Portadores de Fármacos/síntesis química , Ácido Hialurónico/química , Macrófagos/metabolismo , Nanopartículas , Animales , Sitios de Unión , Línea Celular , Quitosano/metabolismo , Materiales Biocompatibles Revestidos/síntesis química , Materiales Biocompatibles Revestidos/metabolismo , Materiales Biocompatibles Revestidos/farmacología , Portadores de Fármacos/metabolismo , Portadores de Fármacos/farmacología , Endocitosis/efectos de los fármacos , Endosomas/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Ácido Hialurónico/metabolismo , Macrófagos/citología , Ratones , Microscopía Fluorescente , Tamaño de la Partícula , Electricidad Estática
13.
J Pharm Sci ; 100(9): 3763-72, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21491458

RESUMEN

The primary aim of this study was to identify structural features that alter the intestinal epithelial permeability and efflux in a series of novel HIV-1 protease inhibitors (PIs). Eleven PIs were selected containing a tertiary alcohol in a transition-state mimicking scaffold, in which two substituents (R(1) and R(2) ) were varied systematically. Indinavir was selected as a reference compound. The apical-to-basolateral permeability was investigated in 2/4/A1 and Caco-2 monolayers. In addition, the basolateral-to-apical permeability was investigated in the Caco-2 monolayers and the efflux ratios were calculated. The absence of active drug transport processes in 2/4/A1 cells allowed identification and modeling of structural elements affecting the passive permeability. For instance, small aromatic R(1) substituents and a small (bromo-) R(2) substituent were associated with a high passive permeability. Efflux studies in Caco-2 cells indicated that amide-substituted neutral hydrophobic amino acids, such as valine and leucine, in the R(1) position, reduced the apical-to-basolateral transport and enhanced the efflux. We conclude that our investigation revealed structural features that alter the intestinal epithelial permeability and efflux in the series of PIs and hope that these results can contribute to the synthesis of PIs with improved permeability and limited efflux properties.


Asunto(s)
Inhibidores de la Proteasa del VIH/farmacocinética , Mucosa Intestinal/fisiología , Células CACO-2 , VIH-1 , Humanos , Permeabilidad
14.
Methods Mol Biol ; 695: 243-59, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21042977

RESUMEN

The impact that nanotechnology may have on life and medical sciences is immense and includes novel therapies as much as novel diagnostic and imaging tools, often offering the possibility to combine the two. It is, therefore, of the essence to understand and control the interactions that nanomaterials can have with cells, first at an individual level, focusing on, e.g., binding and internalization events, and then at a tissue level, where diffusion and long-range transport add further complications. Here, we present experimental methods based on selective labeling techniques and the use of effectors for a qualitative and quantitative evaluation of endocytic phenomena involving nanoparticles. The understanding of the cell-material interactions arising from these tests can then form the basis for a model-based evaluation of nanoparticles behavior in 3D tissues.


Asunto(s)
Endocitosis/efectos de los fármacos , Nanopartículas/toxicidad , Animales , Muerte Celular/efectos de los fármacos , Línea Celular , Citofotometría , Endosomas/efectos de los fármacos , Endosomas/metabolismo , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fluoresceína-5-Isotiocianato , Colorantes Fluorescentes/metabolismo , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Microscopía Confocal , Nanotecnología/métodos
15.
Mol Pharm ; 7(5): 1478-87, 2010 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-20734997

RESUMEN

In this study, the influence of physiologically relevant media on the compound position in a biopharmaceutical classification system (BCS) which resembled the intestinal absorption was investigated. Both solubility and permeability limited compounds (n = 22) were included to analyze the importance of each of these on the final absorption. Solubility was determined in three different dissolution media, phosphate buffer pH 6.5 (PhB 6.5), fasted state simulated intestinal fluid (FaSSIF), and fed state simulated intestinal fluid (FeSSIF) at 37 °C, and permeability values were determined using the 2/4/A1 cell line. The solubility data and membrane permeability values were used for sorting the compounds into a BCS modified to reflect the fasted and fed state. Three of the seven compounds sorted as BCS II in PhB 6.5 (high permeability, low solubility) changed their position to BCS I when dissolved in FaSSIF and/or FeSSIF (high permeability, high solubility). These were low dosed (20 mg or less) lipophilic molecules displaying solvation limited solubility. In contrast, compounds having solid-state limited solubility had a minor increase in solubility when dissolved in FaSSIF and/or FeSSIF. Although further studies are needed to enable general cutoff values, our study indicates that low dosed BCS Class II compounds which have solubility normally restricted by poor solvation may behave as BCS Class I compounds in vivo. The large series of compounds investigated herein reveals the importance of investigating solubility and dissolution under physiologically relevant conditions in all stages of the drug discovery process to push suitable compounds forward, to select proper formulations, and to reduce the risk of food effects.


Asunto(s)
Descubrimiento de Drogas , Absorción Intestinal , Administración Oral , Biofarmacia , Línea Celular , Química Farmacéutica , Ayuno/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Modelos Biológicos , Permeabilidad , Farmacocinética , Prohibitinas , Solubilidad
16.
Expert Opin Drug Deliv ; 7(8): 895-913, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20629604

RESUMEN

IMPORTANCE OF THE FIELD: The last 10 years have seen a dramatic growth in understanding and controlling how complex, drug-loaded (nano)structures, as well as pathogens, or biopharmaceuticals can gather access to the cytoplasm, which is a key step to increasing the effectiveness of their action. AREAS COVERED IN THIS REVIEW: The review offers an updated overview of the current knowledge of endocytic processes; furthermore, the cell surface receptors most commonly used in drug delivery are here discussed on the basis of their reported internalization mechanisms, with examples of their use as nanocarrier targets taken from the most recent scientific literature. WHAT THE READER WILL GAIN: Knowledge of molecular biology details is increasingly necessary for a rational design of drug delivery systems. Here, the aim is to provide the reader with an attempt to link a mechanistic knowledge of endocytic mechanisms with the identification of appropriate targets (internalization receptors) for nanocarriers. TAKE HOME MESSAGE: Much advance is still needed to create a complete and coherent biological picture of endocytosis, but current knowledge already allows individuation of a good number of targetable groups for a predetermined intracellular fate of nanocarriers.


Asunto(s)
Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Endocitosis , Nanopartículas , Receptores de Superficie Celular/metabolismo , Animales , Transporte Biológico , Humanos , Ratones , Nanotecnología , Receptores de Superficie Celular/efectos de los fármacos , Propiedades de Superficie
17.
Pharm Res ; 26(8): 1918-30, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19507009

RESUMEN

PURPOSE: Chitosan is one of the most sought-after components for designing nanoparticles for drug delivery applications. However, despite the large number of studies, reproducibility is often an issue; generally more attention should be focused on purity and precise characterization of the starting material, as well as on the development of robust preparative procedures. METHODS: Using a rational experimental design, we have studied the influence of a number of orthogonal factors (pH, concentrations, ratios of components, different methods of mixing) in the preparation of chitosan/triphosphate (TPP) nanoparticles and in their coating with hyaluronic acid (HA), aiming at the minimisation of size polydispersity, the maximisation of zeta potential and long-term stability, and at the control over average nanoparticle size. RESULTS AND CONCLUSION: Three optimised nanoparticles have been developed (two uncoated and one HA-coated) and their toxicity on fibroblasts and macrophages has been evaluated: experiments showed the beneficial character of HA-coating in the reduction of toxicity (IC50 raised from 0.7-0.8 mg/mL to 1.8 mg/mL) and suggested that the uncoated chitosan/TPP nanoparticles had toxic effects following internalisation rather than membrane disruption.


Asunto(s)
Quitosano/química , Ácido Hialurónico/química , Nanopartículas , Animales , Línea Celular , Quitosano/aislamiento & purificación , Evaluación Preclínica de Medicamentos , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Ratones
18.
Eur J Pharm Sci ; 32(4-5): 296-307, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17920822

RESUMEN

The prolonged residence of drug formulation in the nasal cavity is of utmost importance for intranasal drug delivery. The objective of the present investigation was to develop a mucoadhesive in situ gel with reduced nasal mucociliary clearance in order to improve the bioavailability of the antiemetic drug, metoclopramide hydrochloride (MCP HCl). The in situ gelation upon contact with nasal mucosa was conferred via the use of the thermogelling poloxamer 407 whereas mucoadhesion and drug release enhancement were modulated via the use of mucoadhesive and polyethylene glycol (PEG) polymers respectively. The results revealed that the different mucoadhesives augmented the gel viscosity but reduced its sol-gel transition temperatures (T(sol-gel)) and the drug release. The inclusion of PEG counteracted the effect of the mucoadhesive polymers whereby it decreased the gel consistency and increased the T(sol-gel) as well as the in vitro drug release. The formulations with favorable sol-gel transition temperatures (25-32 degrees C) and high in vitro drug release (100% release in 60 min) were also rheologically stable upon storage. The mucoadhesiveness test was performed in vivo in rats, results showed that the carbopol-containing in situ gel prolonged the mucociliary transport time from 10 min (control solution) to 52 min (mucoadhesive gel) and maintained nasal mucosal integrity after 14-days application. The bioavailability study in rabbits revealed that the absolute bioavailability of MCP HCl was significantly increased from 51.7% in case of the oral drug solution to 69.1% in case of the nasal in situ gel. The study point to the potential of mucoadhesive nasal in situ gel in terms of ease of administration, accuracy of dosing, prolonged nasal residence and improved drug bioavailability.


Asunto(s)
Metoclopramida/administración & dosificación , Metoclopramida/farmacocinética , Depuración Mucociliar/efectos de los fármacos , Mucosa Nasal/efectos de los fármacos , Adhesividad , Administración Intranasal , Animales , Disponibilidad Biológica , Evaluación Preclínica de Medicamentos , Geles/química , Masculino , Metoclopramida/química , Estructura Molecular , Depuración Mucociliar/fisiología , Mucosa Nasal/metabolismo , Conejos , Ratas , Ratas Mutantes , Reología , Temperatura , Factores de Tiempo , Viscosidad
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