Enhancing ovarian cancer conventional chemotherapy through the combination with cannabidiol loaded microparticles.

In this work, we evaluated, for the first time, the antitumor effect of cannabidiol (CBD) as monotherapy and in combination with conventional chemotherapeutics in ovarian cancer and developed PLGA-microparticles as CBD carriers to optimize its anticancer activity. Spherical microparticles, with a mean particle size around 25 µm and high entrapment efficiency were obtained. Microparticles elaborated with a CBD:polymer ratio of 10:100 were selected due to the most suitable release profile with a zero-order CBD release (14.13 ± 0.17 µg/day/10 mg Mps) for 40 days. The single administration of this formulation showed an in vitro extended antitumor activity for at least 10 days and an in ovo antitumor efficacy comparable to that of CBD in solution after daily topical administration (≈1.5-fold reduction in tumor growth vs control). The use of CBD in combination with paclitaxel (PTX) was really effective. The best treatment schedule was the pre + co-administration of CBD (10 µM) with PTX. Using this protocol, the single administration of microparticles was even more effective than the daily administration of CBD in solution, achieving a ≈10- and 8- fold reduction in PTX IC50 respectively. This protocol was also effective in ovo. While PTX conducted to a 1.5-fold tumor growth inhibition, its combination with both CBD in solution (daily administered) and 10-Mps (single administration) showed a 2-fold decrease. These results show the promising potential of CBD-Mps administered in combination with PTX for ovarian cancer treatment, since it would allow to reduce the administered dose of this antineoplastic drug maintaining the same efficacy and, as a consequence, reducing PTX adverse effects.

Stability characteristics of cannabidiol for the design of pharmacological, biochemical and pharmaceutical studies.

Cannabidiol (CBD) is one of the most promising cannabinoids in therapeutics. Nevertheless, the reported stability testing has been carried out with plant extracts and not with CBD as a drug substance. The aim of this work was to evaluate the stability of CBD in solution. A High-Performance Liquid Chromatography (HPLC) analytical method, with CBD in ethanol, was previously validated for these stability studies. The resulting method was linear and proportional in a range of concentrations from 1 to 150 µg CBD/mL, as well as precise. It was also considered suitable to quantify CBD in aqueous medium as reported in accuracy studies. The stability of CBD was influenced by multiple factors. Temperature was one of the most critical parameters, with an activation energy of 92.19KJ/mol. At room temperature, CBD was highly unstable (t95 = 117.13 days). However, at 5 °C it was stable for at least 12 months. CBD was also sensitive to oxidation, with a short t95 of 1.77 days in oxidizing environments, as well as to light. The photolytic reaction seems to be oxidative. The solvent influences CBD stability, and the latter is more stable in ethanol than in aqueous medium. In fact, in simulated physiological conditions (pH 7.4 and 37 °C) 10% of CBD was degraded within 24 h. These studies indicate that CBD is highly unstable, and this should be taken into account in the development of in vitro and in vivo studies of CBD activity and in the pharmaceutical development of dosage forms.

CBD loaded microparticles as a potential formulation to improve paclitaxel and doxorubicin-based chemotherapy in breast cancer.

Cannabidiol (CBD) has emerged as a potential agent for breast cancer management. In this work, the potential use of cannabidiol in solution (CBDsol) and encapsulated in polymeric microparticles when combined with paclitaxel (PTX) and doxorubicin (DOX) in breast cancer treatment has been evaluated for the first time using MCF-7 and MDA-MB-231 cells. CBDsol, previously administered at suboptimal concentrations (cell death < 10%), enhanced the PTX and DOX effect in both breast cancer cells. The co-administration of CBDsol and PTX or DOX showed a synergistic effect. PLGA-502 was selected as the most suitable polymer to develop CBD-loaded microparticles. The developed formulation (CBD-Mps) was effective as monotherapy, showing extended antiproliferative activity for at least 10 days, and when combined with PTX or DOX. In fact, the use of CBD-Mps allows the combination of both, pre and co-administration strategies, with a single administration, also showing a significant increase in PTX and DOX antiproliferative activity. Finally, the anticancer effect of both CBDsol and CBD-Mps as monotherapy or in combination with PTX was also confirmed in ovo, usingMDA-MB-231-derived tumours. This data evidences the promising inclusion of CBD in conventional breast cancer chemotherapy and the use of CBD-Mps for the extended release of this cannabinoid, optimising the effect of the chemotherapeutic agents.

Current status of nanomedicine in the chemotherapy of breast cancer.

Despite the efforts that have been made in the field of breast cancer therapy, it is a leading cause of cancer death in women and a major health problem. The current treatments combine several strategies (surgery, radiotherapy, immunotherapy, hormone therapy, and chemotherapy) depending on cancer subtype and tumour stage. The use of chemotherapy is required in certain circumstances, like before or after surgery or in advanced stages of the disease. Chemotherapeutic regimens that include anthracyclines (e.g. doxorubicin), taxanes (e.g. paclitaxel), 5-fluorouracil and/or cyclophosphamide show, in general, a high toxicity that limit their clinical use. The use of targeted chemotherapy allows to get a selective location of the drug at tumour mass, decreasing the toxicity of these treatments. An increase of the antitumour efficacy can also be achieved. The use of nanocarriers containing anticancer drugs can be a good strategy to get targeted chemotherapy. In fact, several nanoformulations containing paclitaxel and doxorubicin have been approved or are under clinical trial for breast cancer therapy. The main advantage of these nanomedicines is their lower toxicity compared to conventional formulations, which can be attributed to the elimination of the solvents of the formulation (e.g. Cremophor-EL in paclitaxel conventional formulations) and the more selective location of the drug at tumour site (e.g. cardiotoxicity related to free doxorubicin). However, some adverse events (e.g. hand foot syndrome or infusion reactions) have been related to the administration of some nanomedicines, which have to be considered.

Phyto-, endo- and synthetic cannabinoids: promising chemotherapeutic agents in the treatment of breast and prostate carcinomas.

INTRODUCTION: The term 'cannabinoids' designates a family of compounds with activity upon cannabinoid receptors. Cannabinoids are classified in three groups: phytocannabinoids, endocannabinoids, and the synthetic analogues of both groups. They have become a promising tool in the treatment of cancer disease, not only as palliative agents, but also as antitumor drugs, due to their ability to inhibit the proliferation, adhesion, migration, invasion, and angiogenesis of tumour cells. Two of the cancers where they have shown high anticancer activity are breast and prostate tumours. Despite this potential clinical interest, several studies have also reported that cannabinoids can stimulate the proliferation of cancer cells at very low concentrations. Areas covered: The aim of this review is to evaluate the promising chemotherapeutic utility of phytocannabinoids, endocannabinoids, and synthetic cannabinoids in breast and prostate cancer. Expert opinion: Cannabinoids, in particular the non-psychoactive CBD, may be promising tools in combination therapy for breast and prostate cancer, due to their direct antitumor effects, their ability to improve the efficacy of conventional antitumor drugs and their usefulness as palliative treatment. Nevertheless, deeper studies to fully establish the mechanisms responsible for their antitumour and pro-tumour properties and their formulation in efficient delivery systems remain to be established.

HPLC-UV method development and validation for the quantification of ropinirole in new PLGA multiparticulate systems: Microspheres and nanoparticles.

A simple HPLC-UV method was developed and validated for the quantitation of RP free base encapsulated into two new multiparticulate systems (microparticles and nanoparticles), as well as for the quantification of RP hydrochloride when given as a loading dose together with the new delivery system developed. HPLC separation was achieved using a C18 Kromasil column (250 mm × 4 mm) with a mobile phase composed of acetonitrile-phosphate buffer solution (55:45, v/v) adjusted at pH 6.0 and containing 0.3% triethanolamine. Flow rate was set at 1.0 mL min(-1). The UV detector was operated at 245 nm. The method allowed for the simultaneous determination of both RP and RP-HCl. The method was linear within the range 2.5-50 µg mL(-1) for both RP and RP-HCl. The limits of detection (LOD) and quantitation (LOQ) found were 0.8 µg mL(-1) and 2.4 µg mL(-1) for RP, and 0.3 µg mL(-1) and 0.9 µg mL(-1) for RP-HCl. The method was found to be simple, rapid, specific, precise, accurate, and reproducible. The method was successfully applied to the determination of the encapsulation efficiency of RP in the multiparticulate systems developed, being 85.03 ± 3.77% and 51.12 ± 3.50%, for RP-loaded PLGA microspheres and RP-loaded PLGA nanoparticles, respectively.

New celecoxib multiparticulate systems to improve glioblastoma treatment.

Treatment of malignant gliomas consists of resection followed by radiotherapy and chemotherapy. Celecoxib (CXB), a selective COX-2 inhibitor, is able to control inflammation and pain, to improve the efficacy of radiotherapy, and to inhibit at high doses the growth of cancer cells. Two new delivery systems for CXB are developed: microspheres (MPs) for implantation in the brain after partial/complete removal of the tumor, and nanoparticles (NPs) for their potential to cross the blood brain barrier and deliver CXB into the CNS. Cell culture assays performed in PC12, SKN-AS and U373-MG cells demonstrate the antiproliferative affects of CXB, with EC50 values of 99.81 µM and 82.4 µM in U373-MG and SKN-AS cells. Encapsulation efficacy of CXB in formulation MP2 (20% CXB) was 74.6 ± 2.2% with a zero-order release rate of 47.8 µg/day/20mg microspheres for 34 days. Uncoated and polysorbate 80-coated CXB-NPs are prepared by nanoprecipitation. Mean sizes of uncoated and coated CXB-NPs were 173.6 ± 44.9 nm and 100.6 ± 62.1 nm. Cerebral cortex images showed a marked increase of fluorescence when the surfactant-coated NPs were administered to rats. These results suggest that both CXB formulations (MPs and NPs) are adequate systems to enhance the effects of chemotherapy in the treatment of malignant brain tumor.

Controlled release of rasagiline mesylate promotes neuroprotection in a rotenone-induced advanced model of Parkinson's disease.

Microencapsulation of rasagiline mesylate (RM) into PLGA microspheres was performed by method A (O/W emulsion) and method B (W/O/W double emulsion). The best formulation regarding process yield, encapsulation efficiency and in vitro drug release was that prepared with method A, which exhibited constant drug release for two weeks (K(0)=62.3 µg/day/20mg microspheres). Exposure of SKN-AS cells to peroxide-induced oxidative stress (1 mM) resulted in cell apoptosis which was significantly reduced by RM (40.7-102.5 µM) as determined by cell viability, ROS production and DNA fragmentation. Daily doses of rotenone (2 mg/kg) given i.p. to rats for 45 days induced neuronal and behavioral changes similar to those occurring in PD. Once an advanced stage of PD was achieved, animals received RM in saline (1 mg/kg/day) or encapsulated within PLGA microspheres (amount of microspheres equivalent to 15 mg/kg RM given on days 15 and 30). After 45 days RM showed a robust effect on all analytical outcomes evaluated with non-statistically significant differences found between its administration in solution or within microparticles however; with this controlled release system administration of RM could be performed every two weeks thereby making this new therapeutic system an interesting approach for the treatment of PD.

Protective effects of clioquinol on human neuronal-like cells: a new formulation of clioquinol-loaded PLGA microspheres for Alzheimer's disease.

BACKGROUND: Clioquinol (CQ), a metal chelator, has gained renewed attention due to its ability to modulate metal homeostasis in neurodegenerative disorders such as Alzheimer's disease. PURPOSE: To investigate the protective effects of a wide range of concentrations of CQ on two human neuroblastoma cell lines (IMR-32 and SKN-AS) and to develop and characterize a new controlled release system of CQ consisting of biodegradable microspheres. RESULTS: H(2)O(2) (400 µM) adequately induced death cell in IMR-32 and SKN-AS cell lines thereby resulting in a useful model for neuroprotective studies. CQ (20-50 µM) induced a potent and robust protective effect against peroxide-mediated oxidative stress in human neuronal-like cells (SKN-AS) determined by both MTT and flow cytometry (cell viability). These results were also confirmed by means of reactive oxygen species (ROS) production. Biodegradable poly(dl-lactic-co-glycolic acid) (PLGA) resomers assayed for microspheres preparation were PLGA-502 and PLGA-502H. Optimization by using an experimental design resulted in a formulation prepared with CQ (112 mg) and PLGA-502H (400 mg). With this formulation, mean encapsulation efficiency of 82.37% ± 6.67% and, zero-order release rate of 58 ± 3µg CQ/day/10 mg microspheres between Days 10 and 35 were obtained. CONCLUSION: We have developed a promising formulation for the treatment of Alzheimer's disease.

Los estilos de aprendizaje y su relación con las TIC en la adaptación al EEES de los estudios de farmacia / Learning styles and their relationship with the Technologies of Information and Communication (TIC) in the adaptation of pharmacy studies to the ESHE

Introducción: El conocimiento de los estilos de aprendizaje es fundamental para el docente a fin de comprender cómo aprenden sus alumnos y así modificar/reforzar su estilo de enseñanza. La aplicación de las nuevas Tecnologías de la Comunicación y de la Información (TIC) facilita la adaptación de las enseñanzas universitarias al Espacio Europeo de Educación Superior (EEES).Objetivo: Evaluar el estilo de aprendizaje de los alumnos de Farmacia de la Universidad Complutense de Madrid (UCM) y comparar dichos estilos con las TIC. Metodología: Alumnos de 4º curso de licenciatura en Farmacia y de postgrado. Todos respondieron al cuestionario CHAEA de estilos de aprendizaje. Además, se ha planteado un nuevo cuestionario para correlacionar estilos de aprendizaje y TIC. Discusión: Las puntuaciones positivas más elevadas correspondieron al estilo reflexivo seguido del teórico. Más del 80% de los alumnos muestran preferencia muy elevada por las clases magistrales (puntuaciones 4-5, siendo 5 la puntación de máxima preferencia). Este resultado estaría en concordancia con el estilo mayoritario de aprendizaje de los alumnos evaluados. Más del 90% de los alumnos valora de forma altamente positiva (4-5) la impartición de clases mediante la utilización de presentaciones en PowerPoint y, a continuación la utilización de la pizarra y la proyección de videos. Conclusiones: El estilo de aprendizaje de los alumnos de cuarto curso de Farmacia y de postgrado es fundamentalmente reflexivo aunque valoran de forma altamente positiva la utilización de las TIC, lo que confirma la importancia de su uso en la consecución de los objetivos del EEES(AU)

Introduction: knowledge of the learning styles of Pharmacy students is an important tool that can be used to improve teaching thereby reinforcing the use of appropriate and transferable teaching strategies. For this, the use of the Technologies of Information and Communication (TIC) may facilitate the implementation of the European Space for Higher Education (ESHE). Objective: To evaluate the learning styles of graduate and postgraduate pharmacy students at the Universidad Complutense of Madrid and, to compare the student´s learning styles with their preferences regarding the use of the TIC. Methods: The study was performed on fourth-year pharmacy students and postgraduate students. The instrument used to analyze the learning styles was the CHAEA questionnaire. Moreover, a new questionnaire was developed and implemented in order to establish a correlation between learning styles and TIC. Results: The preferred learning styles corresponded to reflexive and, in second place, theoretical learning. More than 80% of the students highly graded traditional lectures (4-5, being 5 the grade for maximum preference), with this result in accordance with the main learning style of the population assayed. More than 90% of the students also positively graded (4-5) multimedia presentations using Power Point software, followed by the use of blackboard and videos. Conclusions: The main learning style of fourth-year graduate students and postgraduate students at the School of Pharmacy (UCM) is reflexive. The populations assayed highly and positively graded the use of TIC, thereby stating their importance in the implementation of the ESHE(AU)

Effective antiproliferative effect of meloxicam on prostate cancer cells: development of a new controlled release system.

Recent studies have shown that COX-2 inhibitors, such as meloxicam, have demonstrated promising results when used with chemotherapy. Based on these findings, this is the first study in which the antiproliferative effect of meloxicam is investigated on two prostate cancer cell lines (PC3 and DU-145). We have also evaluated if this antiproliferative effect is dose- and/or time-dependent. Meloxicam is assayed at a concentration range of 10-800 microM for 24, 48 and 72 h. Our results reveal that meloxicam has a selective dose- and time-dependent antiproliferative effect against PC3 but not against DU-145 cells. In PC3 cells the IC(50) decreased from 740 microM at 24 h to 515 microM at 72 h after meloxicam treatment. Chemoembolization based on microspheres has been emerged as a novel and promising way for antitumoural therapy; therefore, in our study we have developed and characterized a new controlled release system consisting of biodegradable PLGA/PEG-derivative meloxicam microspheres. The optimized formulation has a mean particle size of 13.06+/-0.09 microm, mean encapsulation efficiency of 58.44+/-4.53% and releases 0.45+/-0.05 microg meloxicam/day/mg microspheres between days 3 and 28 of the in vitro release assay. In conclusion, we should consider meloxicam as a possible adjuvant agent in the treatment of prostate cancer.

PLGA/PEG-derivative polymeric matrix for drug delivery system applications: Characterization and cell viability studies.

The incorporation of additives such as polyoxyethylated oleic acid glycerides (PEG-derivative) can modify the release of drugs from microparticles. PEG-derivative decreases the release rate of drugs that are dissolved in PLGA matrices but if un-dissolved the initial release rate slightly increases. To clarify this behaviour the influence of adding PEG-derivative in the preparation of microspheres was investigated by scanning electron microscopy, differential scanning calorimetry, gel permeation chromatography, nuclear magnetic resonance and infrared spectroscopy. Cytotoxicity of this resulting PLGA/PEG-derivative matrix was evaluated in cell lines (fibroblasts) which are more reproducible but less specific and in primary cell cultures (splenocytes and human leucocytes) which have the advantage of their specificity. Scanning electron microscopy revealed that PLGA/PEG-derivative microspheres exhibited small surface concavities with a highly porous polymeric matrix. The incorporation of PEG-derivative caused a slight reduction in the T(g) values of PLGA. In vitro degradation studies showed that PEG-derivative remains within the microspheres as long as the matrix does. This PLGA/PEG-derivative matrix was well tolerated exhibiting cell viabilities similar to PLGA microspheres and can be used to modulate the release of drugs from microparticulate systems destined for parenteral administration.

Biodegradable ibuprofen-loaded PLGA microspheres for intraarticular administration. Effect of Labrafil addition on release in vitro.

The objective of this study was the development and optimisation of biodegradable PLGA microspheres loaded with ibuprofen destined for intraarticular administration. The formulation was designed to provide "in vitro" therapeutic concentrations of ibuprofen (8 microg/ml) for as long as possible. The solvent evaporation method based on an o/w emulsion was used to form the microparticles. The polymer used was Poly (D,L-lactide-co-glicolide) 50:50 (PLGA), of different molecular weights (Mw) (34,000, 48,000 and 80,000 Da). In order to get a more controlled release rate of ibuprofen, a biodegradable oil, Labrafil M1944CS, polyethylene glycol 300 derivative, was used as an additive. The formulation was optimised by means of an experimental design, 2(3) being the variables: X(1) = PLGA Mw; X(2) = initial ibuprofen:polymer ratio; X(3) = percentage of Labrafil. The theoretical profile yielding in vitro "therapeutic" concentrations of ibuprofen (8 microg/ml) was calculated. The experimental profiles obtained for the formulations tested were compared with the theoretical one by means of the difference factor (f(1)). In all cases, the addition of Labrafil lowered the initial ibuprofen burst, prolonging the release rate of the drug from 24 h (without additive) up to 8 days incorporating the oil. The microspheres made from the PLGA (Mw = 34,000 Da) with Labrafil addition (10%) and ibuprofen:polymer (15%) ratio (formulation 1) yielded the most suitable release profiles. Forty milligram of the selected formulation (formulation 1), was sufficient to provide in vitro "therapeutic" concentrations of ibuprofen (8 microg/ml) up to 8 days. Labrafil modulates the release rate of donor-acceptor substances such as ibuprofen.

Sterilized ibuprofen-loaded poly(D,L-lactide-co-glycolide) microspheres for intra-articular administration: effect of gamma-irradiation and storage.

The aim of this study was to prepare and characterize a controlled-release system (microspheres) loaded with ibuprofen, for intra-articular administration, to extend its anti-inflammatory effect in the knee joint cavity. Among the bioresorbable polymers employed, poly(D,L-lactic-co-glycolic) acid (PLGA) (13137 Da) was chosen because of its high biocompatiblity. Microspheres were produced by the solvent evaporation process from an O/W emulsion. Labrafil M 1944 CS was included in the formulation as an additive in order to modulate the release rate of the non-steroidal anti-inflammatory drug (NSAID). Once prepared, the microspheres were sobre-sterilized by gamma-irradiation. The effect of the irradiation dose (25 kGy) exposure, at low temperature, on the formulation was evaluated. The sterilization procedure employed did not alter the physicochemical characteristics of the formulation. Dissolution profiles of formulations behaved similarly and overlapped (f2=87.23, f1=4.2) before and after sterilization. Size Exclusion Chromatography (SEC) revealed no significant changes in the polymer molecular weight. Additionally, a stability study of the sterilized formulation was carried out using microsphere storage conditions of 4 degrees C in a vacuum desiccator for 1 year. The results obtained after storing the sterilized microspheres show no significant alterations in the ibuprofen release rate (f2 = 85.06, f1 = 4.32) or in the molecular weight of the PLGA (12957 Da). The employment of low molecular weight PLGA polymers resulted as advantageous, due to the practical absence of degradation after gamma irradiation (25 kGy) exposure at low temperature.

Enhancement of the mydriatic response to tropicamide by bioadhesive polymers.

The aim of this work was to evaluate how the addition of mucoadhesive polymers to aqueous solutions affects the ocular response of tropicamide (0.2%; w/v). The polymer solutions tested were carboxymethylcellulose sodium salt (CMC-Na; 1%; w/v), hyaluronic acid sodium salt (HA-Na; 0.1%; w/v) and polyacrylic acid (PAA; 0.2%; w/v). Polymeric solutions were compared to a nonviscous formulation (AS). In vitro mucoadhesion measurements were expressed as a percentage of the adhesion force mucin-mucin, considering this one as 100% mucoadhesion. The values ofmucoadhesion obtained were 172%, 127%, 103% and 87.6% for formulations with CMC, PAA, HA and AS, respectively. The mydriatic response of tropicamide was determined in adult male New Zealand rabbits, weighing 1.7-2 Kg, by pupil diameter measurements at different times after instillation. The area under the mydriatic response-time curve (AUC 0-6 hr) was interpreted as an indication of the bioavailability of tropicamide in each vehicle. The AUC 0-6 hr was related to the in vitro mucoadhesion for each formulation. Tropicamide solutions with CMC-Na and PAA resulted in mucoadhesion and AUC 0-6 hr values approximately 1.9 and 1.4 times higher than AS. Although the solution with HA-Na was less mucoadhesive than PAA, the hyaluronic acid solution resulted in a higher AUC mydriasis/time value. Formulations with HA-Na and PAA presented values of surface tension close to that observed in the lacrimal fluid, with the Imax (maximum pupil diameter) being higher than for CMC-Na and AS. Greater than 90% of the mydriatic effect disappeared 4.5 hr after instillation for PAA and AS. Nevertheless, the mydriatic effect remained up to 5.5 hr for HA-Na and CMC-Na. HA-Na solution enhanced the bioavailability oftropicamide, presenting a value of mucoadhesion similar to the reference mucin-mucin.

Biodegradable PLGA microspheres loaded with ganciclovir for intraocular administration. Encapsulation technique, in vitro release profiles, and sterilization process.

PURPOSE: The purpose of this work was to obtain a sterilized formulation consisting of biodegradable microspheres of poly (DL-lactide-co-glycolide) (PLGA) for intraocular sustained release of ganciclovir. METHODS: Microspheres were prepared using a dispersion of ganciclovir in fluorosilicone oil (FSiO) that was further dispersed in an acetone solution of PLGA [50/50 and inherent viscosity 0.41 dl/g], and emulsified in silicone oil with a surfactant. Once prepared, the formulation was exposed with an effective gamma radiation dose of 2.5 megarads. The release rate data of ganciclovir from the sterilized and nonsterilized batches were compared using the similarity factor (f2). RESULTS: The dispersion of the drug in FSiO contributed to achieving a drug payload of up to 95% of the theoretical in the 300-500 microm microspheres. Ten mg released ganciclovir in vitro at 1.3 microg/h for the first 21 days, but decreased to approximately 0.2 microg/h from day 25 until the end of the release study (42 days). No significant differences in the amounts of encapsulated drug (alpha = 0.05) were observed between the sterilized and nonsterilized microspheres. Furthermore, dissolution profiles of formulations behaved similarly before and after gamma radiation exposure. CONCLUSIONS: The technique of microsphere preparation described resulted in high ganciclovir loading (95%) and prolonged drug release. The ganciclovir formulation behaved similarly before and after the sterilization process.