RESUMO
INTRODUCTION: Desloratadine, a second-generation antihistaminic drug, is poorly watersoluble and requires amelioration of the dissolution rate to improve its pharmacokinetics properties. METHOD: This study investigated the impact of polymer, surfactant types, and concentration on the particle size, zeta potential, and dissolution efficiency of nanosuspensions formulated through the solvent antisolvent precipitation method. To optimize the delivery of Desloratadine nanosuspension, we used Minitab software and a 4-factor, 2-level full factorial design. Physicochemical properties and drug release studies were conducted to evaluate the suggested nanosuspension formulations. The optimization goals included minimizing particle size and zeta potential while maximizing dissolution efficiencies. RESULT: The selected optimal nanosuspension demonstrated favourable values, including a particle size of 478.63 ± 15.67 nm, a zeta potential of -36.24 ± 3.21 mV, and dissolution efficiencies in double distilled water and buffer of 90.29 ± 3.75 % and 93.70 ± 3.67 %, respectively. The optimized formulation was subjected to additional analysis using X-ray powder diffraction (XPRD), scanning and transmission electron microscopy (SEM and TEM), and Fourier-transform infrared spectroscopy (FTIR). CONCLUSION: The optimized nanosuspension formulation also underwent further studies under optimal lyophilization conditions, revealing the effectiveness of mannitol as a cryoprotectant at a concentration of 8%.
RESUMO
Background and purpose: Doxazosin mesylate (DOX) is an antihypertensive drug that possesses poor water solubility and, hence, poor release properties. Both nanosuspensions and self-nanoemulsifying drug delivery systems (SNEDDS) are becoming nanotechnology techniques for the enhancement of water solubility of different drugs. Experimental approach: The study's goal was to identify the best drug delivery system able to enhance the release and antihypertensive effect of DOX by comparing the physical characteristics such as particle size, zeta potential, entrapment efficiency, release rate, and main arterial blood pressure of DOX-loaded nanosuspensions and SNEDDS in liquid and solid form. Key results: DOX nanosuspension preparation had a particle size of 385±13 nm, poly-dispersity index of 0.049±3, zeta potential of 50 ± 4 mV and drug release after 20 min (91±0.43 %). Liquid SNEDDS had a droplet size of 224±15 nm, poly-dispersity index of (0.470±0.01), zeta potential of -5±0.10 mV and DR20min of 93±4 %. Solid SEDDS showed particle size of 79±14 nm, poly-dispersity index of 1±0.00, a zeta potential of -18 ±0.26 mv and DR20min of 100 ±2.72 %. Conclusion: Finally, in terms of the mean arterial blood pressure lowering, solid SNEDDS performed better effect than both liquid SNEDDS and nanosuspension (P >0.05).
RESUMO
PURPOSE: Leydig cell hypoplasia (LCH) type II is a rare disease with only a few cases reported. Patients presented with hypospadias, micropenis, undescended testes, or infertility. In this study, we report a new patient with compound heterozygous variants in the LHCGR gene and LCH type II phenotype. METHODS: Whole exome sequencing (WES) was performed followed by Sanger sequencing to confirm the detected variants in the patient and his parents. RESULTS: A novel missense variant (p.Phe444Cys) was identified in a highly conserved site and is verified to be in trans with the signal peptide's 33-bases insertion variant. CONCLUSION: Our research provides a more comprehensive clinical and genetic spectrum of Leydig cell hypoplasia type II. It highlighted the importance of WES in the diagnosis of this uncommon genetic disorder as well as the expansion of the genotype of LCH type II.
Assuntos
Transtorno 46,XY do Desenvolvimento Sexual , Fenótipo , Receptores do LH , Humanos , Masculino , Receptores do LH/genética , Transtorno 46,XY do Desenvolvimento Sexual/genética , Transtorno 46,XY do Desenvolvimento Sexual/diagnóstico , Sequenciamento do Exoma , Sinais Direcionadores de Proteínas/genética , Mutação de Sentido Incorreto , Erros Inatos do Metabolismo de Esteroides/genética , Alelos , Testículo/anormalidadesRESUMO
This work aims to develop plant extract-loaded electrospun nanofiber as an effective wound dressing scaffolds for topical wound healing. Electrospun nanofibers were fabricated from Syzygium cumini leaf extract (SCLE), poly(lactic-co-glycolic acid) (PLGA), poly(methyl methacrylate) (PMMA), collagen and glycine. Electrospinning conditions were optimized to allow the formation of nanosized and uniform fibers that display smooth surface. Morphology and swelling behavior of the formed nanofibers were studied. In addition, the antibacterial activity of the nanofibers against multidrug-resistant and human pathogens was assessed by agar-well diffusion. Results showed that nanofibers containing Syzygium cumini extract at concentrations of 0.5 and 1% w/v exhibited greater antibacterial activity against the tested Gram-positive (i.e., Staphylococcus aureus, Candida albicans, Candida glabrata and Bacillus cereus) and Gram-negative (i.e., Salmonella paratyphi and Escherichia coli) pathogens compared to the same concentrations of the plain extract. Furthermore, in vivo wound healing was evaluated in Wistar rats over a period of 14 days. In vivo results demonstrated that nanofiber mats containing SCLE and collagen significantly improved wound healing within two weeks, compared to the control untreated group. These findings highlight the potential of fabricated nanofibers in accelerating wound healing and management of topical acute wounds.
RESUMO
In this work, Tamarindus indica (T. indica)-loaded crosslinked poly(methyl methacrylate) (PMMA)/cellulose acetate (CA)/poly(ethylene oxide) (PEO) electrospun nanofibers were designed and fabricated for wound healing applications. T. indica is a plant extract that possesses antidiabetic, antimicrobial, antioxidant, antimalarial and wound healing properties. T. indica leaves extract of different concentrations were blended with a tuned composition of a matrix comprised of PMMA (10 %), CA (2 %) and PEO (1.5 %), and were electrospun to form smooth, dense and continuous nanofibers as illustrated by SEM investigation. In vitro evaluation of T. indica-loaded nanofibers on normal human skin fibroblasts (HBF4) revealed a high compatibility and low cytotoxicity. T. indica-loaded nanofibers significantly increased the healing activity of scratched HBF4 cells, as compared to the free plant extract, and the healing activity was significantly enhanced upon increasing the plant extract concentration. Moreover, T. indica-loaded nanofibers demonstrated significant antimicrobial activity in vitro against the tested microbes. In vivo, nanofibers resulted in a superior wound healing efficiency compared to the control untreated animals. Hence, engineered nanofibers loaded with potent phytochemicals could be exploited as an effective biocompatible and eco-friendly antimicrobial biomaterials and wound healing composites.
Assuntos
Anti-Infecciosos , Celulose/análogos & derivados , Nanofibras , Tamarindus , Animais , Humanos , Polimetil Metacrilato/farmacologia , Nanofibras/química , Cicatrização , Anti-Infecciosos/farmacologia , Extratos Vegetais/química , Antibacterianos/farmacologiaRESUMO
Exploitation of nanocarriers provides a compartment for enclosing drugs to protect them from degradation and potentiate their therapeutic efficiency. In the current study, amitriptyline- and liraglutide-loaded proniosomes were constructed for management of diabetic neuropathy, a serious complication associated with diabetes, that triggers spontaneous pain in patients and results in impaired quality of life. The developed therapeutic proniosomes were extensively characterized via dynamic light scattering, scanning electron microscopy, transmission electron microscopy, and Fourier transform-infrared spectroscopy. High entrapment efficiency could be attained for both drugs in the proniosomes, and the reconstituted amitriptyline- and liraglutide-loaded niosomes possessed spherical morphology and particle sizes of 585.3 nm and 864.4 nm, respectively. In a diabetic neuropathy rat model, oral administration of the developed amitriptyline- and liraglutide-loaded proniosomes significantly controlled blood glucose levels, reduced neuropathic pain, oxidative stress and inflammatory markers, and improved histological structure of the sciatic nerve as compared to the oral and subcutaneous administration of amitriptyline and liraglutide, respectively. Loading of the tricyclic antidepressant amitriptyline and the antidiabetic peptide liraglutide into proniosomes resulted in exceptional control over hyperglycemia and neuropathic pain, and thus could provide an auspicious delivery system for management of neuropathic pain and control of blood glucose levels.
Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Hiperglicemia , Neuralgia , Humanos , Ratos , Animais , Amitriptilina , Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/complicações , Liraglutida/uso terapêutico , Glicemia , Qualidade de Vida , Neuralgia/tratamento farmacológico , Neuralgia/complicações , Lipossomos/química , Hiperglicemia/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológicoRESUMO
The poor water solubility of numerous novel drug candidates presents significant challenges, particularly in terms of oral administration. This limitation can result in various undesirable clinical implications, such as inter-patient variability, poor bioavailability, difficulties in achieving a safe therapeutic index, increased costs, and potential risks of toxicity or inefficacy. Biopharmaceutics Classification System (BCS) class II drugs face particular hurdles due to their limited solubility in the aqueous media of the gastrointestinal tract. In such cases, parenteral administration is often employed as an alternative strategy. To address these challenges, nanosuspension techniques offer a promising solution for enhancing drug solubility and overcoming oral delivery obstacles. This technique has the potential to bridge the gap between drug discovery and preclinical use by resolving problematic solubility. This literature review has delved into contemporary nanosuspension preparation technologies and the incorporation of stabilizing ingredients within the formulation. Furthermore, the manuscript explores nanosuspension strategies for both oral and parenteral/other delivery routes, and separate discussions have been presented to establish a suitable flow that addresses the challenges and strategies relevant to each administration method.
Assuntos
Nanopartículas , Tecnologia , Humanos , Preparações Farmacêuticas , Disponibilidade Biológica , Solubilidade , Administração Oral , Suspensões , Tamanho da PartículaRESUMO
Exploitation of machine learning in predicting performance of nanomaterials is a rapidly growing dynamic area of research. For instance, incorporation of therapeutic cargoes into nanovesicles (i.e., entrapment efficiency) is one of the critical parameters that ensures proper entrapment of drugs in the developed nanosystems. Several factors affect the entrapment efficiency of drugs and thus multiple assessments are required to ensure drug retention, and to reduce cost and time. Supervised machine learning can allow for the construction of algorithms that can mine data available from earlier studies to predict performance of specific types of nanoparticles. Comparative studies that utilize multiple regression algorithms to predict entrapment efficiency in nanomaterials are scarce. Herein, we report on a detailed methodology for prediction of entrapment efficiency in nanomaterials (e.g., niosomes) using different regression algorithms (i.e., CatBoost, linear regression, support vector regression and artificial neural network) to select the model that demonstrates the best performance for estimation of entrapment efficiency. The study concluded that CatBoost algorithm demonstrated the best performance with maximum R2 score (0.98) and mean square error (< 10-4). Among the various parameters that possess a role in entrapment efficiency of drugs into niosomes, the results obtained from CatBoost model revealed that the drug:lipid ratio is the major contributing factor affecting entrapment efficiency, followed by the lipid:surfactant molar ratio. Hence, supervised machine learning may be applied for future selection of the components of niosomes that achieve high entrapment efficiency of drugs while minimizing experimental procedures and cost.
Assuntos
Lipossomos , Nanoestruturas , Aprendizado de Máquina , Algoritmos , LipídeosRESUMO
BACKGROUND: Congenital muscular dystrophies (CMDs) result from genetically inherited defects in the biosynthesis and/or the posttranslational modification (glycosylation) of laminin-α2 and α-dystroglycan (α-DG), respectively. The interaction between both proteins is responsible for the stability and integrity of the muscle cell. We aimed to study the expression profiles of both proteins in two classes of CMDs. SUBJECTS AND METHODS: Whole-exome sequencing (WES) was done for four patients with neuromuscular manifestations. The expression of core α-DG and laminin-α2 subunit in skin fibroblasts and MCF-7 cells was assessed by western blot. RESULTS: WES revealed two cases with nonsense mutations; c.2938G > T and c.4348 C > T, in LAMA2 encodes laminin-α2. It revealed also two cases with mutations in POMGNT1 encode protein O-mannose beta-1,2-N-acetylglucosaminyltransferase mutations. One patient had a missense mutation c.1325G > A, and the other had a synonymous variant c.636 C > T. Immunodetection of core α-DG in skin fibroblasts revealed the expression of truncated forms of core α-DG accompanied by reduced expression of laminin-α2 in POMGNT1-CMD patients and one patient with LAMA2-CMD. One patient with LAMA2-CMD had overexpression of laminin-α2 and expression of a low level of an abnormal form of increased molecular weight core α-DG. MCF-7 cells showed truncated forms of core α-CDG with an absent laminin-α2. CONCLUSION: A correlation between the expression pattern/level of core α-DG and laminin-α2 could be found in patients with different types of CMD.
Assuntos
Laminina , Distrofias Musculares , Humanos , Distroglicanas/genética , Distroglicanas/metabolismo , Fibroblastos/metabolismo , Laminina/genética , Distrofias Musculares/genética , Distrofias Musculares/complicações , Distrofias Musculares/metabolismo , Mutação/genéticaRESUMO
Morphologic design of nanomaterials for a diversity of biomedical applications is of increasing interest. The aim of the current study is to construct therapeutic gold nanoparticles of different morphologies and investigate their effect on ocular retention and intraocular pressure in a glaucoma rabbit model. Poly(lactic-co-glycolic acid) (PLGA)-coated nanorods and nanospheres have been synthesized and loaded with carbonic anhydrase inhibitor (CAI), and characterized in vitro for their size, zeta potential and encapsulation efficiency. Nanosized PLGA-coated gold nanoparticles of both morphologies demonstrated high entrapment efficiency (Ë 98%) for the synthesized CAI and the encapsulation of the drug into the developed nanoparticles was confirmed via Fourier transform-infrared spectroscopy. In vivo studies revealed a significant reduction in intraocular pressure upon instillation of drug-loaded nanogold formulations compared to the marketed eye drops. Spherical nanogolds exhibited a superior efficacy compared to the rod-shaped counterparts, probably due to the enhanced ocular retention of spherical nanogolds within collagen fibers of the stroma, as illustrated by transmission electron microscopy imaging. Normal histological appearance was observed for the cornea and retina of the eyes treated with spherical drug-loaded nanogolds. Hence, incorporation of a molecularly-designed CAI into nanogold of tailored morphology may provide a promising strategy for management of glaucoma.
Assuntos
Glaucoma , Nanopartículas Metálicas , Nanopartículas , Animais , Coelhos , Pressão Intraocular , Inibidores da Anidrase Carbônica/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ouro/uso terapêutico , Glaucoma/tratamento farmacológico , Nanopartículas/química , Córnea , Portadores de Fármacos/química , Tamanho da PartículaRESUMO
High percentage of diabetic people are diagnosed as type 2 who require daily dosing of an antidiabetic drug such as Linagliptin (Lina) to manage their blood glucose levels. This study aimed to develop injectable Lina-loaded biodegradable poly (lactic-co-glycolic acid) (PLGA) in-situ implants (ISIs) to deliver a desired burst effect of Lina followed by a sustained release over several days for controlling the blood glucose levels over prolonged time periods. The morphological, pharmacokinetic, and pharmacodynamic assessments of the Lina-loaded ISIs were performed. Scanning electron microscopy (SEM) study revealed the rapid exchange between the water miscible solvent (N-methyl-2-pyrrolidone; NMP) and water during the ISI preparation, hence enhancing the initial burst Lina release. While, triacetin of lower water affinity could lead to formation of more compact and dense ISI structure with slower drug release. By comparing various ISI formulations containing different solvents and different PLGA concentrations, the ISI containing 40 % PLGA and triacetin was selected for its sustained release of Lina (93.06 ± 1.50 %) after 21 days. The pharmacokinetic results showed prolonged half life (t1/2) and higher area under the curve (AUC) values of the selected Lina-loaded ISI when compared to those of oral Lina preparation. The single Lina-ISI injection produced a hypoglycemic control in the diabetic rats very similar to the daily oral administration of Lina after 7 and 14 days. In conclusion, PLGA-based ISIs confirmed their suitability for prolonging Lina release in patients receiving long-term antidiabetic therapy, thereby achieving more enhanced patient compliance and reduced dosing frequency.
RESUMO
OBJECTIVE: The study of the impact of some inherited defects in glycosylation on the biosynthesis of some lysosomal glycoproteins. Results description: Whole-exome sequencing revealed a homozygous variant; 428G > A; p. (R143K) in SRD5A3 in one patient and a heterozygous one c.46G > A p. (Gly16Arg) in SLC35A2 in the other patient. Both variants were predicted to be likely pathogenic. Lysosome-associated membrane glycoprotein 2 (LAMP2) immunodetection in both cases showed a truncated form of the protein. Cystinosin (CTN) protein appeared as normal and truncated forms in both patients in ratios of the mature to truncated forms of CTN were lower than the control. The levels of the truncated forms of both cellular proteins were higher in the SRD5A3-CDG case compared to the SLC35A2-CDG case. The tetrameric form of cathepsin C (CTSC) was expressed at low levels in both cases with congenital disorder of glycosylation (CDG). SLC35A2-CDG patient had one extra-unknown band while SRD5A3-CDG patient had a missing band of CTSC forms. The expression patterns of lysosomal glycoproteins could be different between different types of CDG.
Assuntos
Defeitos Congênitos da Glicosilação , Humanos , Glicosilação , Defeitos Congênitos da Glicosilação/genética , Defeitos Congênitos da Glicosilação/diagnóstico , Defeitos Congênitos da Glicosilação/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Homozigoto , Lisossomos/metabolismo , Lisossomos/patologia , MutaçãoRESUMO
The brain is a vital organ that is protected from the general circulation and is distinguished by the presence of a relatively impermeable blood brain barrier (BBB). Blood brain barrier prevents the entry of foreign molecules. The current research aims to transport valsartan (Val) across BBB utilizing solid lipid nanoparticles (SLNs) approach to mitigate the adverse effects of stroke. Using a 32-factorial design, we could investigate and optimize the effect of several variables in order to improve brain permeability of valsartan in a target-specific and sustained-release manner, which led to alleviation of ischemia-induced brain damage. The impact of each of the following independent variables was investigated: lipid concentration (% w/v), surfactant concentration (% w/v), and homogenization speed (RPM) on particle size, zeta potential (ZP), entrapment efficiency (EE) %, and cumulative drug release percentage (CDR) %. TEM images revealed a spherical form of the optimized nanoparticles, with particle size (215.76 ± 7.63 nm), PDI (0.311 ± 0.02), ZP (-15.26 ± 0.58 mV), EE (59.45 ± 0.88%), and CDR (87.59 ± 1.67%) for 72 hours. SLNs formulations showed sustained drug release, which could effectively reduce the dose frequency and improve patient compliance. DSC and X-ray emphasize that Val was encapsulated in the amorphous form. The in-vivo results revealed that the optimized formula successfully delivered Val to the brain through intranasal rout as compared to a pure Val solution and evidenced by the photon imaging and florescence intensity quantification. In a conclusion, the optimized SLN formula (F9) could be a promising therapy for delivering Val to brain, alleviating the negative consequences associated with stroke.
Assuntos
Nanopartículas , Acidente Vascular Cerebral , Humanos , Lipídeos , Encéfalo , Acidente Vascular Cerebral/tratamento farmacológico , Tamanho da Partícula , Portadores de FármacosRESUMO
Overexpression of two carbonic anhydrase (CA) isoforms, CA IX and XII, in several hypoxic solid tumors provides an extracellular hypoxic microenvironment, interferes with extra- and intracellular pH regulation, thus favoring hypoxic tumor cell survival, proliferation and metastasis. In the current study, a selective inhibitor for human CA isoforms IX and XII (isatin-bearing sulfonamide, WEG-104), was incorporated into nanosized spherical niosomes at high encapsulation efficiency to allow for an enhanced and sustained antitumor activity. In vivo, administration of WEG-104 that is either free (10 mg/kg) or loaded into niosomes (5 mg/kg) into a mice model of Ehrlich ascites solid tumor resulted in comparable efficacy in terms of reduction of tumor weight and volume. Administration of WEG-104-loaded niosomes (10 mg/kg) exhibited superior antitumor activity compared to the free drug, evidenced by reduced tumor weight and volume, marked reduction in the activity of CA IX and XII, and suppression of HIF-1α and MMP-2. Moreover, prominent increase of caspase 3 and pronounced decrease in VEGF immune expression were observed in the treated animals. Hence, loading of molecularly designed compounds that targets CAs in hypoxic solid tumors into nanosized delivery systems provided an auspicious strategy for limiting solid tumor progression and malignancy.
Assuntos
Anidrases Carbônicas , Neoplasias , Camundongos , Animais , Humanos , Inibidores da Anidrase Carbônica/farmacologia , Lipossomos/uso terapêutico , Neoplasias/tratamento farmacológico , Antígenos de Neoplasias , Anidrases Carbônicas/metabolismo , Anidrases Carbônicas/uso terapêutico , Hipóxia/tratamento farmacológico , Microambiente TumoralRESUMO
Despite significant progress in synthetic polymer chemistry and in control over tuning the structures and morphologies of nanoparticles, studies on morphologic design of nanomaterials for the purpose of optimizing antimicrobial activity have yielded mixed results. When designing antimicrobial materials, it is important to consider two distinctly different modes and mechanisms of activity-those that involve direct interactions with bacterial cells, and those that promote the entry of nanomaterials into infected host cells to gain access to intracellular pathogens. Antibacterial activity of nanoparticles may involve direct interactions with organisms and/or release of antibacterial cargo, and these activities depend on attractive interactions and contact areas between particles and bacterial or host cell surfaces, local curvature and dynamics of the particles, all of which are functions of nanoparticle shape. Bacteria may exist as spheres, rods, helices, or even in uncommon shapes (e.g., box- and star-shaped) and, furthermore, may transform into other morphologies along their lifespan. For bacteria that invade host cells, multivalent interactions are involved and are dependent upon bacterial size and shape. Therefore, mimicking bacterial shapes has been hypothesized to impact intracellular delivery of antimicrobial nanostructures. Indeed, designing complementarities between the shapes of microorganisms with nanoparticle platforms that are designed for antimicrobial delivery offers interesting new perspectives toward future nanomedicines. Some studies have reported improved antimicrobial activities with spherical shapes compared to non-spherical constructs, whereas other studies have reported higher activity for non-spherical structures (e.g., rod, discoid, cylinder, etc.). The shapes of nano- and microparticles have also been shown to impact their rates and extents of uptake by mammalian cells (macrophages, epithelial cells, and others). However, in most of these studies, nanoparticle morphology was not intentionally designed to mimic specific bacterial shape. Herein, the morphologic designs of nanoparticles that possess antimicrobial activities per se and those designed to deliver antimicrobial agent cargoes are reviewed. Furthermore, hypotheses beyond shape dependence and additional factors that help to explain apparent discrepancies among studies are highlighted.
Assuntos
Anti-Infecciosos , Nanopartículas , Nanoestruturas , Animais , Nanopartículas/química , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Polímeros , Transporte Biológico , MamíferosRESUMO
Hemorrhage is a prime cause of death in civilian and military traumatic injuries, whereby a significant proportion of death and complications occur prior to paramedic arrival and hospital resuscitation. Hence, it is crucial to develop hemostatic materials that are able to be applied by simple processes and allow control over bleeding by inducing rapid hemostasis, non-invasively, until subjects receive necessary medical care. This tutorial review discusses recent advances in synthesis and fabrication of degradable hemostatic nanomaterials and nanocomposites. Control of assembly and fine-tuning of composition of absorbable (i.e., degradable) hemostatic supramolecular structures and nanoconstructs have afforded the development of smart devices and scaffolds capable of efficiently controlling bleeding while degrading over time, thereby reducing surgical operation times and hospitalization duration. The nanoconstructs that are highlighted have demonstrated hemostatic efficiency pre-clinically in animal models, while also sharing characteristics of degradability, bioabsorbability and presence of nano-assemblies within their compositions.
Assuntos
Hemostáticos , Animais , Hemorragia/terapia , Hemostasia , Técnicas Hemostáticas/efeitos adversos , Hemostáticos/farmacologia , HumanosRESUMO
Intravenous dexmedetomidine (DEX) is currently approved by the FDA for the sedation of intubated patients in intensive care units to reduce anxiety and to augment postoperative analgesia. Bradycardia and hypotension are limitations associated with the intravenous administration of DEX. In this study, DEX sublingual in situ gels were developed and assessed for their pH, gelling capacity, viscosity, mucoadhesion and in vitro drug release. The optimized gelling system demonstrated enhanced mucoadhesion, superior gelling capacity, reasonable pH and optimal rheological profile. In vivo, compared to the oral solution, the optimal sublingual gel resulted in a significant higher rate and extent of bioavailability. Although the in situ gel had comparable plasma levels to those observed following intravenous administration, significant amelioration of the systemic adverse reactions were attained. As demonstrated by the hot plate method, a sustained duration of analgesia in rats was observed after sublingual administration of DEX gel compared to the intravenously administered DEX solution. Furthermore, no changes in systolic blood pressure and heart rate were recorded in rats and rabbits, respectively, after sublingual administration of DEX. Sublingual administration of DEX in situ gel provides a promising approach for analgesia and sedation, while circumventing the reported adverse reactions associated with intravenous administration of DEX.
RESUMO
Construction of nanocarriers of different structures and properties have shown great promise as delivery systems for a wide range of drugs to improve therapeutic effects and reduce side effects. Nanostructured lipid carriers (NLCs) have been introduced as a new generation of solid lipid nanoparticles (SLNs) to overcome several of the limitations associated with the SLNs. NLCs consist of a blend of solid and liquid lipids which result in a partially crystallized lipid system that enables higher drug loading efficiency compared to SLNs. Owing to their biocompatibility, low toxicity, ease of preparation and scaling-up, and high stability, NLCs have been exploited in numerous pharmaceutical applications. Different methods for fabrication of NLCs have been described in the literature. In this article, procedures involved in emulsification-solvent evaporation method, one of the commonly utilized methods for preparation of NLCs, are described in detail. Critical aspects that should be considered throughout preparation process are also highlighted to allow for consistent and reproducible construction of NLCs.
Assuntos
Nanopartículas , Nanoestruturas , Portadores de Fármacos/química , Lipídeos/química , Lipossomos , Nanopartículas/química , Nanoestruturas/química , Tamanho da PartículaRESUMO
Development of nanocarriers has opened new avenues for the delivery of therapeutics of various pharmacological activities with improved targeting properties and reduced side effects. Niosomes, non-ionic-based vesicles, have drawn much interest in various biomedical applications, owing to their unique characteristics and their ability to encapsulate both hydrophilic and lipophilic cargoes. Niosomes share structural similarity with liposomes while overcoming limitations associated with stability, sterilization, and large-scale production of liposomes. Different methods for preparation of niosomes have been described in the literature, each having its own merits and a great impact on the sizes and characteristics of the formed niosomes. In this article, procedures involved in the thin-film hydration method, a commonly used method for the preparation of niosomes, are described in detail, while highlighting precautions that should be considered for consistent and reproducible construction of niosomes.
Assuntos
Sistemas de Liberação de Medicamentos , Lipossomos , Sistemas de Liberação de Medicamentos/métodos , Lipossomos/química , Tamanho da Partícula , Tensoativos/químicaRESUMO
Inspired by the antitubercular activity of isoniazid (INH) and 5-bromoisatin, isatin-INH hybrid (WF-208) has been synthesized as a potent agent against multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of M. tuberculosis. In silico molecular docking studies indicated that DprE1, a critical enzyme in the synthesis of M. tuberculosis cell wall, is a potential enzymatic target for WF-208. The synthesized WF-208 was incorporated into a nanoparticulate system to enhance stability of the compound and to sustain its antimicrobial effect. Nanosized spherical niosomes (hydrodynamic diameter of ca. 500-600 nm) could accommodate WF-208 at a high encapsulation efficiency of 74.2%, and could impart superior stability to the compound in simulated gastric conditions. Interestingly, WF-208 had minimal inhibitory concentrations (MICs) of 7.8 and 31.3 µg/mL against MDR and XDR M. tuberculosis, respectively, whereas INH failed to demonstrate bacterial growth inhibition at the range of the tested concentrations. WF-208-loaded niosomes exhibited a 4-fold increase in the anti-mycobacterial activity as compared to the free compound (MIC of 1.9 vs. 7.8 µg/mL) against H37Rv M. tuberculosis, after three weeks of incubation with WF-208-loaded niosomes. Incorporation of the compound into nanosized vesicles allowed for a further increase in stability, potency and sustainability of the anti-mycobacterial activity, thus, providing a promising strategy for management of tuberculosis.