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1.
Chem Biol Interact ; 394: 110988, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574834

RESUMO

Epilepsy is a neurological disorder characterized by overstimulation of neurotransmitters and uncontrolled seizures. Current medications for epilepsy result in adverse effects or insufficient seizure control, highlighting the necessity to develop alternative therapies. Cannabidiol (CBD), derived from cannabis plants, has been popularly explored as an alternative. CBD is shown to have anti-convulsivatng and muscle-relaxing properties, which have been used in patients with epilepsy with promising results. Current research explores varying dosages in either adult or paediatric patients, with little or no comparison between the two populations. In this review, we aim at consolidating this data and comparing the effect and pharmacokinetic properties of CBD across these two patient populations. When comparing the absorption, there was insufficient data to show differences between paediatric and adult patients. Similarly, limited information was available in comparing the distribution of CBD, but a higher volume of distribution was found in the paediatric population. From the metabolism perspective, the paediatric population had a greater success rate when treated with the drug compared to the adult population. In the elimination, there were no clear distinctions in the clearance rate between the two populations. The drug's half-life was highly variable in both populations, with paediatrics having a lower range than adults. In summary, the paediatric population had a more significant reduction in the severity of seizures compared to the adult population upon CBD treatment. The complexity in which CBD operates highlights the need for further studies of the compound to further understand why differences occur between these two populations.


Assuntos
Anticonvulsivantes , Canabidiol , Epilepsia , Canabidiol/farmacocinética , Canabidiol/uso terapêutico , Humanos , Epilepsia/tratamento farmacológico , Criança , Adulto , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/uso terapêutico
3.
Artigo em Inglês | MEDLINE | ID: mdl-38036849

RESUMO

In recent year, the research of transdermal drug delivery systems has got substantial attention towards the development of microneedles (MNs). This shift has occurred due to multifaceted advantages of MNs as they can be utilized to deliver the drug deeper to the skin with minimal invasion, offer successful delivery of drugs and biomolecules that are susceptible to degradation in gastrointestinal tract (GIT), act as biosensors, and help in monitoring the level of biomarkers in the body. These can be fabricated into different types based on their applications as well as material for fabrication. Some of their types include solid MNs, hollow MNs, coated MNs, hydrogel forming MNs, and dissolving MNs. These MNs deliver the therapeutics via microchannels deeper into the skin. The coated and hollow MNs have been found successful. However, they suffer from poor drug loading and blocking of pores. In contrast, dissolving MNs offer high drug loading. These MNs have also been utilized to deliver vaccines and biologicals. They have also been used in cosmetics. The current review covers the different types of MNs, materials used in their fabrication, properties of MNs, and various case studies related to their role in delivering therapeutics, monitoring level of biomarkers/hormones in body such as insulin. Various patents and clinical trials related to MNs are also covered. Covered are the major bottlenecks associated with their clinical translation and potential future perspectives.

4.
Int J Biol Macromol ; 224: 810-830, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36302483

RESUMO

Diabetic retinopathy (DR) is one of the chronic complications of diabetes. It includes retinal blood vessels' damage. If untreated, it leads to loss of vision. The existing treatment strategies for DR are expensive, invasive, and need expertise during administration. Hence, there is a need to develop a non-invasive topical formulation that can penetrate deep to the posterior segment of retina and treat the damaged retinal vessels. In addition, it should also provide sustained release. In recent years, novel drug delivery systems (NDDS) have been explored for treating DR and found successful. In this study, chitosan (CS) modified 5-Fluorouracil Nanostructured Lipid Carriers (CS-5-FU-NLCs) were prepared by modified melt emulsification-ultrasonication method and optimized by Box-Behnken Design. The size, polydispersity index, zeta potential and entrapment efficiency of CS-5-FU-NLCs were 163.2 ± 2.3 nm, 0.28 ± 1.52, 21.4 ± 0.5 mV and 85.0 ± 0.2 %, respectively. The in vitro drug release and ex vivo permeation study confirmed higher and sustained drug release in CS-5-FU-NLCs as compared to 5-FU solution. HET-CAM Model ensured the non-irritant nature of CS-5-FU-NLCs. In vivo ocular studies of CS-5-FU-NLCs confirmed antiangiogenic effect of 5-FU by CAM model and diabetic retinopathy induced rat model, indicating successful delivery of 5-FU to the retina.


Assuntos
Antineoplásicos , Quitosana , Diabetes Mellitus , Retinopatia Diabética , Nanoestruturas , Ratos , Animais , Fluoruracila , Portadores de Fármacos , Lipídeos , Tamanho da Partícula , Liberação Controlada de Fármacos
5.
Expert Opin Drug Deliv ; 19(7): 771-793, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35695697

RESUMO

INTRODUCTION: Diabetes mellitus (DM) is the most common metabolic disease and multifactorial, harming patients worldwide. Extensive research has been carried out in the search for novel drug delivery systems offering reliable control of glucose levels for diabetics, aiming at efficient management of DM. AREAS COVERED: Polymeric micelles (PMs) as smart drug delivery nanocarriers are discussed, focusing on oral drug delivery applications for the management of hyperglycemia. The most recent approaches used for the preparation of smart PMs employ molecular features of amphiphilic block copolymers (ABCs), such as stimulus sensitivity, ligand conjugation, and as a more specific example the ability to inhibit islet amyloidosis. EXPERT OPINION: PMs provide a unique platform for self-regulated or spatiotemporal drug delivery, mimicking the working mode of pancreatic islets to maintain glucose homeostasis for prolonged periods. This unique characteristic is achieved by tailoring the functional chemistry of ABCs considering the physicochemical traits of PMs, including sensing capabilities, hydrophobicity, etc. In addition, the application of ABCs for the inhibition of conformational changes in islet amyloid polypeptide garnered attention as one of the root causes of DM. However, research in this field is limited and further studies at the clinical level are required.


Assuntos
Diabetes Mellitus , Micelas , Diabetes Mellitus/tratamento farmacológico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Glucose , Humanos , Polímeros/química
6.
J Pharm Pharm Sci ; 25: 227-236, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35760071

RESUMO

PURPOSE: Between January 2020 and December 2021, Health Canada provided a Summary Basis of Decision (SBD) for each of 110 products approved, including 29 oncology products and 21 non-oncology orphan drugs. This review sought to gain insight into how Real Word Evidence (RWE) impacts regulatory decision making. METHODS: SBDs for oncology drugs and non-oncology orphan drugs were reviewed for evidence of use of the RWE or historical data to support regulatory decisions. This information was compared with both FDA and EMA reviews. RESULTS: For the 29 Health Canada-approved oncology products, 11 were approved with Notice of Compliance with Conditions (NOCc) status. Two NOCc approvals received extensive RWE reviews, while two other approvals briefly mentioned the use of RWE/historical data. Of the 12 NOC approvals, one received RWE reviews. FDA also approved all 29 drugs, 14 of which received extensive comments on RWE and/or historical data and 8 of which mentioned RWE or historical data. EMA approved 25 of the 29 products and provided extensive comments on 10. Four products received a mention of RWE review. The percentages of submissions with RWE/historical reviews conducted by Health Canada, FDA and EMA were 24.1, 75.9 and 56.0 respectively. Of the 21 non-oncology orphan drugs, Health Canada provided priority review status to 11, with extensive RWE comments in 5 and the mention of RWE in 2 of the regular approvals. Two approvals that used third-party data were not included in the comparison. FDA approved 19, and provided extensive RWE assessment on 5 and mentioned use of historical data in 8. EMA approved 17 and provided extensive RWE and historical comments in 7 and mentioned historical data in 4. The percentages of submissions with RWE/historical reviews by Health Canada, FDA and EMA were 36.8, 68.4 and 64.7 respectively. CONCLUSIONS: Use of Real World Data is common among FDA/EMA reviews and Health Canada used RWE in recent NOCc and orphan drug approvals.


Assuntos
Tomada de Decisões , Aprovação de Drogas , Canadá
7.
Nanomedicine (Lond) ; 17(12): 827-843, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35437998

RESUMO

Aims: Inhalation of vaping additives has recently been shown to impair respiratory function, leading to e-cigarette or vaping product use associated with lung injuries. This work was designed to understand the impact of additives (vitamin E, vitamin E acetate, tetrahydrocannabinol and cannabidiol) on model lung surfactants. Materials & methods: Lipid monofilms at the air-water interface and Brewster angle microscopy were used to assess the impact of vaping additives on model lung surfactant films. Results & conclusion: The addition of 5 mol % of vaping additives, and even more so mixtures of vitamins and cannabinoids, negatively impacts lipid packing and film stability, induces material loss upon cycling and significantly reduces functionally relevant lipid domains. This range of detrimental effects could affect proper lung function.


The increasing use of vaping products in young adults and the emergence of associated lung injuries have resulted in significant health concerns for healthcare professionals and the public alike. These detrimental effects were linked to additives such as vitamin E and cannabinoids. The deep lung is composed of many small compartments, where oxygen is taken up into the body. The ultimate barrier between the outer gas phase and the lung cells is a layer composed of mainly lipids and some proteins, the lung surfactant. The authors present data for lung surfactant models based on the composition of human lung surfactant. The selected components reflect key lung surfactant roles, stability upon exhalation and fast spreading after inhalation. Additives have recently been shown to impair respiratory function, leading to e-cigarette or vaping product use associated lung injuries. This work was designed to understand the impact of additives (vitamin E, vitamin E acetate, tetrahydrocannabinol and cannabidiol) on model lung surfactants. All tested additives, and more so their mixtures, clearly affected the lung surfactant model in terms of stability and elasticity, which impairs its ability to perform the aforementioned roles. Lipid monofilms at the air­water interface and Brewster angle microscopy were used to assess the impact of vaping additives on model lung surfactant films. The addition of 5 mol % of vaping additives, and even more so mixtures of vitamins and cannabinoids, negatively impacts lipid packing and film stability, induces material loss upon cycling and significantly reduces functionally relevant lipid domains. This range of detrimental effects could affect proper lung function.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Surfactantes Pulmonares , Vaping , Lipídeos , Pulmão , Tensoativos , Vaping/efeitos adversos , Vitamina E
8.
Res Pharm Sci ; 17(2): 111-122, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35280840

RESUMO

Background and purpose: Benjakul (BJK) is a combination of five botanical herbal constituents widely used in Thai traditional medicine as an anti-inflammatory remedy. This study aimed to develop a novel topical microemulsion containing BJK for clinical use. Experimental approach: The microemulsions were produced by a phase inversion temperature (PIT) methodology. Physicochemical properties and stability were evaluated to determine an optimal formula. The stable BJK-loaded microemulsion formulas were then subjected to in vitro studies for their anti-inflammatory activity, skin cell toxicity, drug permeation, and stability. Finding/Results: Two novel formulations containing isopropyl myristate (ME1-BJK and ME2-BJK) passed the compendial stability test. BJK constituents were completely dissolved in the oil phase and incorporated into the microemulsion base Transcutol® and Labrasol® avoiding the use of alcohol, both microemulsion formulations demonstrated high anti-inflammatory activity with IC50 values of 3.41 ± 0.36 and 3.95 ± 1.73 µg/mL, respectively. However, dissolution of ME1-BJK showed a superior release profile through both lipophilic and hydrophilic membranes with the highest accumulated amount at 4 h of 25.13% and 38.06%, respectively. All tested formulations of BJK extract demonstrated no apparent skin cell toxicity at concentrations up to 50 µg/mL. After six-month storage under accelerated conditions, there were no significant changes in anti-inflammatory activity. Conclusions and implications: A novel and stable BJK-loaded microemulsion formulation was successfully developed with excellent release and stability properties. Further clinical research to evaluate pain reduction, edema, and skin irritation using this formulation in animal models is ongoing.

9.
Chem Biol Interact ; 356: 109869, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35231453

RESUMO

Fisetin (FS) is a bioactive flavonoid obtained mostly from apple and strawberry and classified under the category of food supplements due to numerous pharmacological effects against various diseases through multiple mechanistic pathways. It acts as excellent neuroprotective, cardioprotective, anti-invasive, anti-tumorigenic, anti-angiogenic, anticancer, antidiabetics, antioxidant, anti-inflammatory agent. Despite having excellent safety and efficacy profile, FS is very less explored to clinical research either as food supplement or, as therapeutic agent due to its poor aqueous solubility, low bioavailability and reduced blood brain barrier permeability. Multiple mechanistic pathways through which FS elicits its pharmacological actions and the challenges associated with FS that compromises therapeutic efficacy are described in this article. The nanoformulations developed to enhance the bioavailability and therapeutic efficacy of FS are also covered with detailed description of research works carried by various researchers. These include nanoemulsions, liposomes, ethosomes, glycerosomes, polymeric micelles, self-nanoemulsifying drug delivery system and polymeric nanoparticles. Various patents pertaining to extraction/isolation, formula composition and therapeutic uses of FS as well as some clinical studies conducted using FS as active moiety are also enlisted.


Assuntos
Flavonóis , Nanopartículas , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos
10.
Nanomedicine (Lond) ; 17(30): 2231-2243, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36853835

RESUMO

Aims: Vaping has given rise to e-cigarette or vaping product use-associated lung injury. Model lung surfactant films were used to assess the impact of vape additives (vitamin E, vitamin E acetate, tetrahydrocannabinol, cannabidiol). This work builds upon our previous findings, by incorporating cholesterol, to understand the interplay between the additives and the sterol in surfactant function. Materials & methods: Compression-expansion cycles of lipid monofilm at the air-water interface and Brewster angle microscopy allowed elucidating the effects of vape additives. Results & conclusion: Vape additives at 5 mol% inhibited proper lipid packing and reduced film stability. Cholesterol enhanced the additive effects, resulting in significantly destabilized films and altered domains. The observed impact could signify dysfunctional lung surfactant and impaired lung function.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Lesão Pulmonar , Vaping , Humanos , Vaping/efeitos adversos , Lesão Pulmonar/induzido quimicamente , Tensoativos , Colesterol , Vitamina E , Pulmão
11.
Clin Invest Med ; 44(1): E15-24, 2021 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-33743572

RESUMO

PURPOSE: To investigate a novel composite methodology of using targeted serum microRNAs (micro ribonucleic acid; miRNA) and urine metabolites for the accurate detection of early stage non-small cell lung cancer (NSCLC). METHODS: Consecutively consenting NSCLC patients and matched control subjects were recruited to provide samples of serum for miRNA and/or urine for metabolite analyses. Serum miRNA levels were measured using quantitative real-time reverse-transcription with exogenous control, and the comparative delta cycle threshold (CT) method was used to calculate relative miRNA expression of two targeted miRNAs (miR-21 and miR-223). The concentrations of six targeted urinary metabolites in patients and healthy controls were measured using proton nuclear magnetic resonance (1H NMR) spectroscopy. A composite methodology of using the 35 accruals with both serum and urine biomarkers was then established with binary logistic regression, receiver operating characteristic (ROC) models with or without artificial intelligence (AI). RESULTS: The ROC analysis of miRNA expression yielded a sensitivity of 96.4% and a specificity of 88.2% for the detection of early stage NSCLC, with area under the curve (AUC) = 0.91 (CI 95%: 0.80-1.0). Relative urinary concentrations of 4-methoxyphenylacetic acid (4MPLA) were significantly different between NSCLC and healthy control (p=0.008). The ROC analysis of 4MPLA yielded a sensitivity of 82.1% and a specificity of 88.2%, with AUC = 0.85. The composite process combining miRNA and metabolite expression demonstrated a sensitivity and specificity of nearly 100% and AUC=1. CONCLUSIONS: A highly specific, sensitive and non-invasive detection method for NSCLC was developed. Pending validation, this can potentially improve the early detection and, hence, the treatment and survival outcomes of patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Inteligência Artificial , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Detecção Precoce de Câncer , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Curva ROC
12.
AAPS PharmSciTech ; 22(2): 54, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33475891

RESUMO

This work describes an exploratory experimental and in silico study of the influence of polymorphism, particle size, and physiology on the pharmacokinetics of lercanidipine hydrochloride (LHC). Equilibrium and kinetic solubility studies were performed on LHC forms I and II, as a function of pH and buffer composition. GastroPlus® was used to evaluate the potential effect of solubility differences due to polymorphism, particle size, and physiological conditions, on the drug pharmacokinetics. The results indicated that solubilities of LHC polymorphs are strongly dependent on the composition and pH of the buffer media. The concentration ratio (CI/CII) is particularly large for chloride buffer (CI/CII = 3.3-3.9) and exhibits a slightly decreasing tendency with the pH increase for all other buffers. Based on solubility alone, a higher bioavailability of form I might be expected. However, exploratory PBPK simulations suggested that (i) under usual fasted (pH 1.3) and fed (pH 4.9) gastric conditions, the two polymorphs have similar bioavailability, regardless of the particle size; (ii) at high gastric pH in the fasted state (e.g., pH 3.0), the bioavailability of form II can be considerably lower than that of form I, unless the particle size is < 20 µm. This study demonstrates the importance of investigating the effect of the buffer nature when evaluating the solubility of ionizable polymorphic substances. It also showcases the benefits of using PBPK simulations, to assess the risk and pharmacokinetic relevance of different solubility and particle size between crystal forms, for diverse physiological conditions.


Assuntos
Di-Hidropiridinas/química , Disponibilidade Biológica , Di-Hidropiridinas/farmacocinética , Humanos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Solubilidade
13.
Artigo em Inglês | MEDLINE | ID: mdl-32877636

RESUMO

A joint Canadian Society for Pharmaceutical Sciences and Health Canada workshop entitled "Biowaiver for Immediate and Modified Release Dosage forms" was held in Ottawa, November 19th 2015. A summary of all presentations is included.


Assuntos
Preparações Farmacêuticas/administração & dosagem , Equivalência Terapêutica , Disponibilidade Biológica , Biofarmácia , Canadá , Química Farmacêutica , Congressos como Assunto , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Humanos , Preparações Farmacêuticas/química , Preparações Farmacêuticas/normas
14.
Eur J Pharm Biopharm ; 152: 257-269, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32422167

RESUMO

This study aimed to design the ideal nanonizing vehicle for poorly water-soluble model curcumin (CCM) using fattigation-platform nanotechnology, and to investigate the effects of fatty acid salts chain length on nanonizing CCM and its efficient delivery to different cancer cells. HSA-fatty acid conjugates were synthesized by EDC/NHS coupling. Fattigation-platform nanomicelles (NMs), prepared by film hydration, exhibited uniform and spherical morphology, although, each NM varied in particle size, zeta potential, and critical micelle concentration according to the types of fatty acid. Preliminary solubility studies of albumin conjugates with 5 types of fatty acid salts of different chain lengths revealed that C14 exhibited the highest solubilization of CCM. CCM-loaded HSA-C14 NMs demonstrated the highest drug content (5.35 ± 0.48%) and loading efficiency (95.93 ± 1.87%) compared to other NMs. It exhibited enhanced drug release rate and reduced micelle size in biorelevant dissolution medium. Interestingly, this solubilization approach was well applied in poorly water-soluble docetaxel trihydrate (DTX). Preliminary solubility results of DTX was also corresponded to the stable nanonization phenomenon in biorelevant dissolution medium. Compared to the CCM EtOH solution, HSA-C14 NMs showed higher internalization in cancer cell lines A549 and MCF-7, and consequently, exhibited significantly increased cytotoxicity against both cell lines. Therefore, this study provides a new solubilization approach for poorly water-soluble drugs using fatty acid salts of different chain lengths and their micellar formations via nanonization, which could be a promising tool for targeted cancer therapy using poorly water-soluble drugs.


Assuntos
Albuminas/química , Portadores de Fármacos/química , Ácidos Graxos/química , Nanopartículas/química , Água/química , Células A549 , Linhagem Celular , Linhagem Celular Tumoral , Curcumina/química , Docetaxel/química , Liberação Controlada de Fármacos/efeitos dos fármacos , Células HEK293 , Humanos , Células MCF-7 , Micelas , Nanotecnologia/métodos , Tamanho da Partícula , Solubilidade
15.
J Control Release ; 324: 55-68, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32380202

RESUMO

The aims of this study were to design different chain length fatty acid-conjugated albumin nanoparticles (ANPs) and evaluate their anticancer activity in the HCT116 human colorectal cancer xenograft mouse model. Doxorubicin hydrochloride (DOX·HCl) was chosen as a model drug. The different chain lengths of fatty acids (butyric acid; C4, and stearic acid; C18) in albumin conjugates exhibited different physicochemical properties and anticancer activity. Fatty acid-conjugated albumin aided the formation of self-assembled structures with an average size of approximately 200 nm and a negative charge when incubated with excess DOX in an aqueous solution. DOX-loaded long-chain C18-conjugated ANPs allowed efficient encapsulation of hydrophobic DOX into the core of the self-assembled structure, enabling higher drug loading, enhanced colloidal stability and controlled release behavior in PBS pH 7.4 medium as compared with free DOX·HCl or non-fatty acid conjugated ANPs. Furthermore, DOX-loaded fatty acid-conjugated ANPs showed an increased cellular uptake intensity and cytotoxic effects in vitro. In vivo, HCT116 xenograft model experiments confirmed that DOX-loaded C18-conjugated ANPs showed improved anticancer activity and reduced side effects compared with the DOX-treated groups. The long-chain fatty acid-conjugated ANPs synergistically activated the interaction with the free-fatty acid receptor (FFAR) on HCT116 colorectal cancer cells as compared with short-chain C4 or other non-conjugated ANPs. Specifically, DOX-loaded C18-conjugated NPs exhibited significant performance to overexpressed FFAR4 on HCT116 colorectal cancer cells. The fatty acid chain length in the fattigation-platform system could be a promising molecular moiety to improve targeting efficiency and drug accumulation in various cancer therapy.


Assuntos
Neoplasias Colorretais , Nanopartículas , Albuminas , Animais , Neoplasias Colorretais/tratamento farmacológico , Doxorrubicina , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Ácidos Graxos , Xenoenxertos , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Pharm Pharm Sci ; 21(1): 143-159, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29789104

RESUMO

PURPOSE: Silibinin, is a natural compound, which has shown anticancer activity in various malignancies. In this study, we evaluated the anticancer effects of silibinin in B16-F10 melanoma cells and developed a novel thermoresponsive hydrogel for local delivery of this compound. METHOD: A thermoresponsive hydrogel loaded with silibinin was prepared using triblock copolymers of poly[(α-benzyl carboxylate-e-caprolactone)-co-(α-carboxyl-e-caprolactone)]ran-b-PEG-b-[(α-benzyl carboxylate-e-caprolactone) -co-(α-carboxyl-e-caprolactone)]ran (PCBCL-b-PEG-b-PCBCL), namely PolyGelTM, and compared with a Pluronic F-127 formulation of silibinin. Sol-gel transition temperature of hydrogels was measured by inverse flow method and modulated differential scanning calorimetry (MDSC). Silibinin loading efficiency was measured by HPLC. The MTT and clonogenic assays were used to assess the cytotoxicity and anti-proliferative effects of silibinin on B16-F10 melanoma cells. Flow cytotmetry was used to quantify the induced level of apoptosis and measure the intracellular level of activated STAT3 (pSTAT3) following silibinin treatment in B16.F10 cells. The effects of silibinin on the activation of oncogenic proteins were also evaluated by western blot. RESULTS: Silibinin inhibited cell proliferation (IC50 = 67 µM), provoked cell cycle arrest, induced apoptosis, suppressed key oncogenic pathways (i.e STAT3 and MEK/ERK), and enhanced the cytotoxic effects of doxorubicin in B16-F10 cells. Both PolyGelTM and Pluronic F-127 hydrogels were effective in loading silibinin. A lower drug release pattern within 24h, fitting first- order release kinetics, was observed for the release of silibinin from both gels compared to free drug.  PolyGelTM demonstrated enhanced percutaneous absorption of silibinin through increasing mouse skin intracellular lipid fluidity as documented by DSC of skin following PolyGelTM use. Silibinin loaded in PolyGel TM inhibited the growth of B16-F10 cells (IC50 = 30 µM) and effectively suppressed pSTAT3 activity in B16-F10 cells at 10 µM. CONCLUSION: Our results imply a great potential for PolyGel TM formulations of silibinin for local treatment of malignant melanoma. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's content page.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Caproatos/química , Lactonas/química , Melanoma/tratamento farmacológico , Polietilenoglicóis/química , Silibina/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Temperatura , Animais , Antineoplásicos Fitogênicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Hidrogéis/química , Hidrogéis/farmacologia , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Silibina/química , Neoplasias Cutâneas/patologia , Melanoma Maligno Cutâneo
17.
Mol Pharm ; 14(12): 4281-4294, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-28737409

RESUMO

In this study, we determined the pH and buffer capacity of human gastrointestinal (GI) fluids (aspirated from the stomach, duodenum, proximal jejunum, and mid/distal jejunum) as a function of time, from 37 healthy subjects after oral administration of an 800 mg immediate-release tablet of ibuprofen (reference listed drug; RLD) under typical prescribed bioequivalence (BE) study protocol conditions in both fasted and fed states (simulated by ingestion of a liquid meal). Simultaneously, motility was continuously monitored using water-perfused manometry. The time to appearance of phase III contractions (i.e., housekeeper wave) was monitored following administration of the ibuprofen tablet. Our results clearly demonstrated the dynamic change in pH as a function of time and, most significantly, the extremely low buffer capacity along the GI tract. The buffer capacity on average was 2.26 µmol/mL/ΔpH in fasted state (range: 0.26 and 6.32 µmol/mL/ΔpH) and 2.66 µmol/mL/ΔpH in fed state (range: 0.78 and 5.98 µmol/mL/ΔpH) throughout the entire upper GI tract (stomach, duodenum, and proximal and mid/distal jejunum). The implication of this very low buffer capacity of the human GI tract is profound for the oral delivery of both acidic and basic active pharmaceutical ingredients (APIs). An in vivo predictive dissolution method would require not only a bicarbonate buffer but also, more significantly, a low buffer capacity of dissolution media to reflect in vivo dissolution conditions.


Assuntos
Líquidos Corporais/química , Motilidade Gastrointestinal/fisiologia , Trato Gastrointestinal/fisiologia , Ibuprofeno/farmacocinética , Absorção Intestinal/fisiologia , Absorção Fisiológica , Administração Oral , Adulto , Líquidos Corporais/fisiologia , Soluções Tampão , Liberação Controlada de Fármacos , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Mucosa Intestinal/fisiologia , Manometria , Pessoa de Meia-Idade , Solubilidade , Comprimidos , Equivalência Terapêutica , Fatores de Tempo , Adulto Jovem
18.
J Pharm Pharm Sci ; 19(3): 312-324, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27806246

RESUMO

BACKGROUND: We assessed the feasibility of using crystal-liquid fugacity ratio (CLFR) as an alternative parameter for intestinal permeability in the biopharmaceutical classification (BCS) of passively absorbed drugs. METHODS: Dose number, fraction of dose absorbed, intestinal permeability, and intrinsic dissolution rate were used as the input parameters. CLFR was determined using thermodynamic parameters i.e., melting point, molar fusion enthalpy, and entropy of drug molecules obtained using differential scanning calorimetry. RESULTS: The CLFR values were in the range of 0.06-41.76 mole percent. There was a close relationship between CLFR and in vivo intestinal permeability (r > 0.8). CLFR values of greater than 2 mole percent corresponded to complete intestinal absorption. Applying CLFR versus dose number or intrinsic dissolution rate, more than 92% of tested drugs were correctly classified with respect to the reported classification system on the basis of human intestinal permeability and solubility. CONCLUSION: This investigation revealed that the CLFR might be an appropriate parameter for quantitative biopharmaceutical classification. This could be attributed to the fact that CLFR could be a measure of solubility of compounds in lipid bilayer which was found in this study to be directly proportional to the intestinal permeability of compounds. This classification enables researchers to define characteristics for intestinal absorption of all four BCS drug classes using suitable cutoff points for both intrinsic dissolution rate and crystal-liquid fugacity ratio. Therefore, it may be used as a surrogate for permeability studies. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.


Assuntos
Intestinos/efeitos dos fármacos , Cristais Líquidos/química , Preparações Farmacêuticas/química , Termodinâmica , Biofarmácia , Humanos , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Permeabilidade/efeitos dos fármacos , Preparações Farmacêuticas/metabolismo , Solubilidade
19.
Pak J Pharm Sci ; 28(6): 2001-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26639477

RESUMO

Eczema is characterized by itching, lichenification, scaling, oedema and erythema. Current management strategies include corticosteroids, which are limited due to side effects. Many herbal remedies are used traditionally but unfortunately have not been validated in controlled clinical trials. Three popular traditional treatments of eczema include Indian pennywort, Walnut and Turmeric. In this study three topical formulations (micro emulsion, gel and ointment) were prepared from extracts of Indian pennywort, Walnut and Turmeric. These formulations were monitored for stability for a period of three months. Controlled clinical trials were conducted on 360 eczema patients. Clinical parameters observed were degree of erythema, oedema, scaling, itching and lichenification. Effects of each formulation on these clinical parameters were compared with placebo formulations. Micro emulsion formulations in all cases proved to be more effective in reducing semi quantitative scores of erythema and oedema. Itching was relieved more by gel formulation. The ointment showed more efficacy towards scaling and lichenification. Comparison of the effects of placebo and the specific formulations was performed by chi-square statistics and found to be highly significant. In summary it is concluded that all the formulations could be used as promising source for treatment of eczema.


Assuntos
Centella , Curcuma , Fármacos Dermatológicos/administração & dosagem , Eczema/tratamento farmacológico , Juglans , Extratos Vegetais/administração & dosagem , Administração Cutânea , Centella/química , Química Farmacêutica , Distribuição de Qui-Quadrado , Curcuma/química , Fármacos Dermatológicos/química , Método Duplo-Cego , Eczema/diagnóstico , Emulsões , Feminino , Géis , Humanos , Juglans/química , Masculino , Pomadas , Paquistão , Fitoterapia , Extratos Vegetais/química , Folhas de Planta , Caules de Planta , Plantas Medicinais , Rizoma , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
20.
J Pharm Pharm Sci ; 18(2): 177-83, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26158283

RESUMO

The Canadian Society for Pharmaceutical Sciences organized a workshop on the current state of sciences of subsequent entry biologics (SEBs, biosimilars) on December 10th 2014 in the Health Canada location in Ottawa, ON. The day-long workshop provided an opportunity to discuss recent regulatory developments and a wide range of scientific issues related to SEBs. Following a discussion on the differences between the Canadian guidance and those of other countries,  a series of presentations were made that focused on the regulatory requirements with regard to the product quality, methodology, non-clinical and clinical data. In addition, issues of extrapolation from one indication to another, interchangeability and reimbursement  were articulated. It was also highlighted that both the patients and caregivers need to be better informed regarding the safety and efficacy of articulated SEBs.


Assuntos
Medicamentos Biossimilares , Medicamentos Biossimilares/efeitos adversos , Medicamentos Biossimilares/farmacologia , Medicamentos Biossimilares/normas , Canadá , Humanos
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