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Gliomas are primary brain tumors originating from glial cells, representing 30% of all Central Nervous System (CNS) neoplasia. Among them, the astrocytoma grade IV (glioblastoma multiforme) is the most common, presenting an invasive and aggressive profile, with an estimated life expectancy of about 15 months after diagnosis even after treatment with radiation, surgical resection, and chemotherapy. This poor prognosis is related to the presence of the blood-brain barrier (BBB) and multidrug resistance mechanisms that prevent the uptake and retention of chemotherapeutics inside the brain. Gene therapy has been a promising strategy to overcome these treatment limitations since it has the ability to modify the defective genetic information in tumor cells, being able to induce cellular apoptosis and silence the genes responsible for multidrug resistance. Lipidbased nanoparticles, non-viral vectors, have been investigated to deliver genes across the BBB to reach the glioma cell target. Besides, their low immunogenicity, easy production, ability to incorporate ligands to specific target cells, and capacity to carry higher size genes have made the gene therapy based on non-viral vectors a promising glioma treatment. In this context, this review addresses the most common non-viral vectors based on lipid-based nanoparticles used for glioma gene therapy, such as liposomes, solid lipid nanoparticles, nanostructured lipid carriers, and nanoemulsions.

In vitro 3D culture models have emerged in the cancer field due to their ability to recapitulate characteristics of the in vivo tumor. Herein, we described the establishment and characterization of 3D multicellular spheroids using ovarian cancer cells (SKOV-3) in co-culture with mesenchymal cells (MUC-9) or fibroblasts (CCD27-Sk). We demonstrated that SKOV-3 cells in co-culture were able to form regular and compact spheroids with diameters ranging from 300 to 400 µm and with a roundness close to 1.0 regardless of the type of stromal cell used. In the 3D culture an increase was not observed in spheroid diameter nor was there significant cell growth. What is more, the 3D co-cultures presented an up regulation of genes related to tumorigenesis, angiogenesis and metastases (MMP2, VEGFA, SNAI1, ZEB1 and VIM) when compared with 2D and 3D monoculture. As expected, both 3D cultures (mono and co-cultures) exhibited a higher Paclitaxel chemoresistance when compared to 2D condition. Although we did not observe differences in the Paclitaxel resistance between the 3D mono and co-cultures, the gene expression results indicate that the presence of mesenchymal cells and fibroblasts better recapitulate the in vivo tumor microenvironment, being able, therefore, to more accurately evaluate drug efficacy for ovarian cancer therapy.

Made available in DSpace on 2022-05-01T16:48:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-07-20 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Breast cancer is the commonest cancer among women, with more than 2 million cases per year and a lethality rate of 17.7%. The treatment of breast cancer still being a challenge due to the high heterogeneity of tumor cells. In this scenario, the development of targeted nanosystems for drug delivery has been investigated. Thus, the aim of this study was the development and characterization of folic acid-modified curcumin-loaded liposomes (LIP-CCM-FA) for the treatment of breast cancer. For this purpose, LIP-CCM-FA and unmodified liposomes (LIP-CCM) were developed and characterized in vitro using MCF-7 cells culture in two-dimensional (2D) and three-dimensional (3D) models. LIP-CCM and LIP-CCM-FA showed low particles size (~ 138 nm), narrow polydispersity indexes (~ 0.140), negative zeta potential (~ −13 mV), and high drug encapsulation efficiency (> 73%). Furthermore, LIP-CCM-FA showed a significantly greater cytotoxicity effect when compared with free curcumin and LIP-CCM using 2D and 3D cell culture models. In addition, in vitro cellular uptake assays using 2D and 3D models indicated higher cellular internalization and spheroid penetration of LIP-CCM-FA when compared with free curcumin and LIP-CCM, suggesting the potential of folic acid modification for improving drug internalization in breast cancer cells through its recognition by folate receptors overexpressed. In summary, this novel nanosystem demonstrated a greater in vitro antitumoral effect due to its ability to permeate tissues and be specifically recognized by folate receptors. School of Pharmaceutical Science of Ribeirao Preto University of Sao Paulo (USP) School of Pharmaceutical Science of Sao Paulo State University (UNESP), Sao Paulo School of Pharmaceutical Science of Sao Paulo State University (UNESP), Sao Paulo CAPES: 001

Epirubicin (EPI) is a chemotherapeutic agent belonging to the anthracycline drug class indicated for treating several tumors. It acts by suppressing the DNA and RNA synthesis by intercalating between their base pair. However, several side effects are associated with this therapy, including cardiotoxicity and myelosuppression. Therefore, EPI delivery in nanosystems has been an interesting strategy to overcome these limitations and improve the safety and efficacy of EPI. Thus, analytical methods have been used to understand and characterize these nanosystems, including spectrophotometric, spectrofluorimetric, and chromatography. Spectrophotometric and spectrofluorimetric methods have been used to quantify EPI in less complex matrices due to their efficiency, low cost, and green chemistry character. By contrast, high-performance liquid chromatography is a suitable method for detecting EPI in more complex matrices (e.g., plasm and urine) owing to its high sensitivity. This review summarizes physicochemical and pharmacokinetic properties of EPI, its application in drug delivery nanosystems, and the analytical methods employed in its quantification in different matrices, including blood, plasm, urine, and drug delivery nanosystems.

The objective of this study was to develop and characterize lipid nanoparticles (LNs) containing chloroaluminum phthalocyanine (ClAlPc) to reduce the aggregation of the drug and improve its skin penetration and its antitumor effect. LNs were prepared and characterized by using stearic acid (SA) as solid lipid and oleic acid (OA) as liquid lipid in different proportions. in vitro and in vivo skin penetration was evaluated using modified Franz diffusion cells and fluorescence microscopy, respectively. in vitro biocompatibility and Photodynamic Therapy (PDT) were performed using L929-fibroblasts cell line and A549 cancer cell line and melanoma BF16-F10, respectively. OA promoted the increase in the encapsulation efficiency and drug loading, reaching values of 95.8% and 4%, respectively. The formulation with 40% OA (NLC 40) showed a significantly higher (p 0.01) amount of drug retained in the skin compared to other formulations. All formulations developed were considered biocompatible. PDT evidenced the antitumor efficacy of NLC 40 with reduced cell viability for approximately 10% of cancer cells, demonstrating that the presence of OA in the NLC seems to potentialize this antitumor effect. PDT in BF16-F10 melanoma using NLC 40 resulted in a reduction in mean cell viability of approximately 99%. According to the results obtained, the systems developed may be promising for the incorporation of ClAlPc in the treatment of skin cancer by photodynamic therapy.

Made available in DSpace on 2021-06-25T10:49:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-20 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Prostate cancer is one of the most frequent neoplasms, associated with high mortality. Some factors may intensify its aggressiveness, for example, the overexpression of the epidermal growth factor receptor (EGFR) in some subtypes of prostate tumors. In this context, the inhibition of EGFR helps to fight neoplasia, with the use of the chimeric anti-EGFR monoclonal antibody, cetuximab (CTX). For cancer treatment in the metastatic stage, chemotherapy using docetaxel (DTX) is widely employed, however the drug is very liposoluble, hampering its bioavailability. In this sense, liquid crystalline systems have great potential for the delivery of DTX. Particularly, liquid crystalline nanodispersions can be used in parenteral routes, with many advantages, including the possibility of prolonged drug release, improved pharmacokinetics, allowing passive tumor accumulation by the EPR effect. Thus, the objective of this work was to develop a liquid crystalline nanodispersion (LCN) based on ethoxylated cetyl alcohol 20 and propoxylated 5 as surfactant (Procetyl®), oleic acid, DSPE-PEG-MAL (anchor for CTX binding) and soy phosphatidylcholine as oily phase and 1.5 % poloxamer dispersion in PBS buffer as an aqueous phase. The formulation was loaded with DTX and covalently functionalized with CTX to evaluate its cytotoxic potential against prostate cancer cells. The results suggested that the obtained system has a predominantly hexagonal crystalline phase, was able to be nanodispersed with low polydispersity, and presented negative zeta potential. CTX did not have its structure compromised after thiolation and was successfully covalently linked to LCN. In a prostate cancer cells, PC3, LCNs functionalized with CTX underwent greater cell uptake, resulting in greater cytotoxicity, compared to free DTX and non-functionalized DTX-loaded LCNs. Therefore, the present study reports for the first time an EGFR-targeted liquid crystal nanodispersion for selective to deliver DTX to prostate cells School of Pharmaceutical Sciences of Araraquara São Paulo State University UNESP Department of Drugs and Medicines Federal University of Ceará College of Pharmacy Dentistry and Nursing Department of Pharmacy University of International Integration of the Afro-Brazilian Lusophony Institute of Health Sciences São Carlos Institute of Chemistry University of São Paulo, São Carlos School of Pharmaceutical Sciences of Ribeirão Preto University of São Paulo Ribeirão Preto School of Pharmaceutical Sciences of Araraquara São Paulo State University UNESP Department of Drugs and Medicines CNPq: # 465687/2014-8 FAPESP: #2014/50928-2

Made available in DSpace on 2021-06-25T11:06:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-02-20 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Prostate cancer (PC) is the second type of cancer, causing the greatest number of deaths among the male population in the world. An attractive approach to treat PC involves the superficial modification of liposomes with specific ligands to overexpressed receptors on the surfaces of tumor cells, such as transferrin receptors (TFR's). To our knowledge, this is the first time that transferrin-functionalized liposomes for delivery of DTX to prostate cancer cells were investigated. In this study, we developed and characterized docetaxel- loaded liposomes functionalized with transferrin (LIP-DTX-TF) and evaluated their effect on PC cell lines. The results showed that the systems had a nanometric size and the presence of DTX contributed to the reduction of the vesicle size and liposomes were stable. The encapsulation efficiency of DTX was approximately 69 and 37 % for liposomes with and without functionalization, respectively. The functionalization efficiency using TF was 31 %. The functionalization process did not affect the integrity of TF. DTX encapsulated in the liposomes showed slow and sustained release for LIP-DTX and LIP-DTX-TF (51.70 % and 31.97 %, respectively). The in vitro cytotoxicity assay in PC-3 and PNT2 cell lines suggest that LIP-DTX-TF was more toxic to PC-3 than the commercial formulation. Confocal microscopy proved that functionalized liposomes were successfully internalized in PC-3 cells. Furthermore, the interaction of these systems with the TFR's overexpressed on the cell surface was further corroborated using Quartz Crystal Microbalance with Dissipation technology (QCM-D). Therefore, although additional studies in three-dimensional cell models and in vivo xenograft studies are warranted, it can be concluded that the systems developed here are promising candidates for the delivery of docetaxel to prostate cancer cells. School of Pharmaceutical Sciences São Paulo State University (UNESP) College of Pharmacy Dentistry and Nursing Federal University of Ceara (UFC) School of Pharmaceutical Science of Ribeirão Preto University of São Paulo (USP) São Carlos Institute of Chemistry University of São Paulo (USP) School of Pharmacy and Pharmaceutical Sciences Trinity Biomedical Sciences Institute Trinity College Dublin the University of Dublin School of Biochemistry and Immunology Trinity Biomedical Sciences Institute Trinity College Dublin the University of Dublin School of Medicine Trinity Biomedical Sciences Institute Trinity College Dublin the University of Dublin School of Pharmaceutical Sciences São Paulo State University (UNESP) CNPq: # 465687/2014-8 FAPESP: #2014/50928-2

The acquired drug chemoresistance represents the main challenge of the ovarian cancer treatment. In addition, the absence of an adequate in vitro model able to reproduce the native tumor environment can contribute to the poor success rate of pre-clinical studies of new compounds. Three-dimensional (3D) culture models have been recently used for drug screening purposes due to their ability to reproduce the main characteristics of in vivo solid tumors. Here we describe the establishment and characterization of 3D ovarian cancer spheroids using different adenocarcinoma tumor cell lines (SKOV-3 and OVCAR-3 cells) in two different 3D scaffold-free methods: forced-floating in ultra-low attachment (ULA) plates and hanging drop (HD). Spheroids were evaluated in both 3D cultures in order to establish the best condition to perform the drug response analysis with Paclitaxel, a common drug used to treat ovarian cancer. SKOV-3 and OVCAR-3 spheroids with the desired characteristics (roundness close to 1.0 and diameter in the 200-500 μm range) were obtained using both methods after addition of the methylcellulose (MC) in the culture medium (0.25% and 0.5%, w/v). We also observed the presence of microvilli on the surface of the spheroids, higher presence of apoptotic cells and higher drug resistance, when compared with 2D cultures. The 3D cultures obtained seem to provide more reliable results in terms of drug response than those provided by 2D monolayer culture. The forced floating method was considered more suitable and straightforward to generate ovarian cancer spheroids for drug screening/cytotoxicity assays.

Made available in DSpace on 2022-05-01T05:29:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-08-01 Nanotechnology has been widely applied to develop drug delivery systems to improve therapeutic performance. The effectiveness of these systems is intrinsically related to their physicochemical properties, so their biological responses are highly susceptible to factors such as the type and quantity of each material that is employed in their synthesis and to the method that is used to produce them. In this context, quality-oriented manufacturing of nanoparticles has been an important strategy to understand and to optimize the factors involved in their production. For this purpose, Design of Experiment (DoE) tools have been applied to obtain enough knowledge about the process and hence achieve high-quality products. This review aims to set up the bases to implement DoE as a strategy to improve the manufacture of nanocarriers and to discuss the main factors involved in the production of the most common nanocarriers employed in the pharmaceutical field. School of Pharmaceutical Sciences of Ribeirao Preto University of Sao Paulo Department of Computer Science Federal University of Minas Gerais, Belo Horizonte School of Pharmaceutical Sciences Sao Paulo State University Department of Chemistry Faculty of Philosophy Sciences and Letters of Ribeirao Preto University of São Paulo School of Pharmaceutical Sciences Sao Paulo State University

Made available in DSpace on 2020-12-12T02:11:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-10-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Prostate cancer is the second cause of cancer death in men worldwide. Docetaxel (DTX), an antimitotic drug, is widely used for the treatment of metastatic prostate cancer patients. Taxotere® is a commercial DTX formulation. It contains a polysorbate 80 surfactant to improve DTX aqueous solubility, which has been associated with hypersensitivity reactions in patients. Liposomes have been used as promising delivery systems for a range of hydrophobic drugs, such as DTX, offering improved drug water solubility and biocompatibility, without compromising its anticancer activity. Herein, DTX-loaded liposomes were developed using the Box-Behnken factorial design. The optimized formulation was nano-sized, homogenous in size (67.47 nm) with high DTX encapsulation efficiency (99.95 %). The encapsulated DTX was in a soluble amorphous state, which was slowly released. Next, to increase the liposomes selectivity to prostate cancer cells, cetuximab, an anti-EGFR monoclonal antibody. was successfully conjugated to the surface of liposomes, without compromising cetuximab protein structure and stability. As expected, our results showed higher cellular uptake and toxicity of immunoliposomes, compared to non-targeted liposomes, in DU145 (EGFR-overxpressing) prostate cancer cells. To the best of our knowledge, this is the first report of engineering EGFR-targeted liposomes to enhance the selectivity of DTX delivery to EGFR-positive prostate cancer cells. Federal University of Ceará College of Pharmacy Dentistry and Nursing Department of Pharmacy School of Pharmacy Queen's University Belfast, 97 Lisburn Rd School of Pharmaceutical Sciences of Araraquara São Paulo State University UNESP Department of Drugs and Medicines University for International Integration of the Afro-Brazilian Lusophony Institute of Health Sciences College of Pharmaceutical Sciences of Ribeirão Preto University of São Paulo São Carlos Institute of Chemistry University of São Paulo School of Pharmaceutical Sciences of Araraquara São Paulo State University UNESP Department of Drugs and Medicines

Prostate cancer is the second most common type of cancer in men, remaining the second leading cause of cancer-related deaths in this gender. In order to improve the security and efficacy of its treatment, nanostructured delivery systems have been widely studied. The present work aimed to develop and characterize polymeric nanoparticles based on a copolymer of polycaprolactone-DL-α-tocopherol-polyethylene glycol-1000 (PCL-block-TPGS) containing docetaxel (PN-DTX) for prostate cancer therapy. TPGS was used in nanoparticle composition due to its ability to inhibit the P-glycoprotein, an efflux pump related with multidrug resistance. PCL-block-TPGS PN-DTX were obtained by the nanoprecipitation technique and characterized by their physicochemical, morphological and biological characteristics in vitro and in vivo. The systems were successfully obtained and had suitable size distribution, polydispersity index, zeta potential encapsulation efficiency and loading capacity for the proposed objectives (130 ± 18 nm, 0.10 ± 0.04, −30.1 ± 2.3 mV, 96.2 ± 1.1% and 5.01 ± 0.32%, respectively). The encapsulation efficiency was confirmed by calorimetric and spectroscopic studies. Biological assays demonstrated the high ability of PN-DTX to cause cell death and to be internalized in PC-3 cell line, reaching EC50 of 0.476 ± 0.092 nM and internalization of 97.64 ± 1.21%. In vivo studies demonstrated efficacy of the system developed in an animal model with a reduction of tumor volume in 40.1% and 18.0% when compared with control and DTX commercial formulation groups, respectively. Therefore, docetaxel-loaded PCL-block-TPGS polymeric nanoparticle is a potential system for prostate cancer treatment.

Glioma is the most common type of Central Nervous System (CNS) neoplasia and it arises from glial cells. As glial cells are formed by different types of cells, glioma can be classified according to the cells that originate it or the malignancy grade. Glioblastoma multiforme is the most common and aggressive glioma. The high lethality of this tumor is related to the difficulty in performing surgical removal, chemotherapy, and radiotherapy in the CNS. To improve glioma treatment, a wide range of chemotherapeutics have been encapsulated in nanosystems to increase their ability to overcome the blood-brain barrier (BBB) and specifically reach the tumoral cells, reducing side effects and improving drug concentration in the tumor microenvironment. Several studies have investigated nanosystems covered with targeting ligands (e.g., proteins, peptides, aptamers, folate, and glucose) to increase the ability of drugs to cross the BBB and enhance their specificity to glioma through specific recognition by receptors on BBB and glioma cells. This review addresses the main targeting ligands used in nanosystems to overcome the BBB and promote the active targeting of drugs for glioma. Furthermore, the advantages of using these molecules in glioma treatment are discussed.

Made available in DSpace on 2021-06-25T11:13:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Glioblastoma multiforme (GBM) is a first primary Central Nervous System tumor with high incidence and lethality. Its treatment is hampered by the difficulty to overcome the blood-brain barrier (BBB) and by the non-specificity of chemotherapeutics to tumor cells. This study was based on the development characterization and in vitro efficacy of folate-modified TPGS transfersomes containing docetaxel (TF-DTX-FA) to improve GBM treatment. TF-DTX-FA and unmodified transfersomes (TF-DTX) were prepared through thin-film hydration followed by extrusion technique and characterized by physicochemical and in vitro studies. All formulations showed low particles sizes (below 200 nm), polydispersity index below 0.2, negative zeta potential (between −16.75 to −12.45 mV) and high encapsulation efficiency (78.72 ± 1.29% and 75.62 ± 0.05% for TF-DTX and TF-DTX-FA, respectively). Furthermore, cytotoxicity assay of TF-DTX-FA showed the high capacity of the nanocarriers to reduce the viability of U-87 MG in both 2D and 3D culture models, when compared with DTX commercial formulation and TF-DTX. In vitro cellular uptake assay indicated the selectivity of transfersomes to tumoral cells when compared to normal cells, and the higher ability of TF-DTX-FA to be internalized into 2D U-87 MG in comparison with TF-DTX (72.10 and 62.90%, respectively, after 24 h). Moreover, TF-DTX-FA showed higher permeability into 3D U-87 MG spheroid than TF-DTX, suggesting the potential FA modulation to target treatment of GBM. School of Pharmaceutical Science of Ribeirao Preto University of Sao Paulo (USP) School of Pharmaceutical Sciences Sao Paulo State University (UNESP) School of Pharmaceutical Sciences Sao Paulo State University (UNESP) CAPES: 001 FAPESP: 2014/50928-2

Adenocarcinoma is the most lethal gynecologic tumor and treatment usually consists in surgery followed by chemotherapy. However, the chemotherapy benefits are eventually limited due to drug toxicity to normal tissues and cells, which cause several and harsh side effects. Paclitaxel (PCX) is the drug of first choice for ovarian cancer treatment, but it has low aqueous solubility, which reduces its bioavailability. Thus, in the commercial drug, Taxol®, PCX is solubilized in a mixture of toxic surfactants. The development of drug nanocarriers has been investigated to promote the reduction of toxic effects and increase the safety and therapeutic efficacy of PCX. The aim of this work was the development and characterization of PCX loaded nanoparticles (PNPCX) and evaluation of in vitro efficacy of developed system using adenocarcinoma cell line. The nanocarrier was successfully obtained using nanoprecipitation technique. The results showed that the PNPCX-A had a particle size distribution around 140 nm and polydispersity index smaller than 0.1, with high PCX encapsulation efficiency. The results obtained were suitable for the intravenous administration route and promotion of passive targeting in the tumor microenvironment. The in vitro cytotoxicity assays of SKOV-3 cell line demonstrated that PNPCX-A was able to release PCX and reduce cell viability. The flow cytometry assays first reported that a nanostructured system with such composition (PNPCX-A) presented a time dependent cellular uptake, showing the ability of nanocarrier to be internalized. PNPCX-A present a distinguish potential for ovarian cancer therapy optimization. In vivo studies are needed to confirm the in vitro results and provide additional data regarding safety and efficacy of ovarian cancer treatment.

Nanotechnology has been applied in the medicine field to improve the treatment of a wide range of diseases. However, to reach the nanomedicines delivery to desirable target tissue for promote an enhancement of pharmacological activity, these nanomedicines must overcome biological barriers, such as mucus gel, skin, corneal and blood–brain barriers. Aiming the increase nanomedicines permeation through these barriers, surface modifications of nanocarriers with permeation enhancers and/or specific ligands for cellular receptors have been widely investigated. Among these modifications, d-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) is a biocompatible macromolecule that has been evaluated as a permeation enhancer. TPGS is a non-ionic surfactant composed by the natural vitamin E bonded with polyethylene glycol 1000 (PEG) and its composition have been responsible to enhance cellular internalization and permeation of nanomedicines through biological barriers. In addition, this molecule has acted as solubilizer, emulsifier, stabilizer and P-glycoprotein (P-gp) inhibitor, that are important features to manufacture nanomedicines with suitable to overcome barriers and multidrug resistance (MDR) mechanisms. This review will address the TPGS physicochemical and biological features and its most recent application in nanomedicine field to overcome biological barriers.

Paclitaxel and rapamycin have been reported to act synergistically to treat breast cancer. Albeit paclitaxel is available for breast cancer treatment, the most commonly used formulation in the clinic presents side effects, limiting its use. Furthermore, both drugs present pharmacokinetics drawbacks limiting their in vivo efficacy and clinic combination. As an alternative, drug delivery systems, particularly liposomes, emerge as an option for drug combination, able to simultaneously deliver co-loaded drugs with improved therapeutic index. Therefore, the purpose of this study is to develop and characterize a co-loaded paclitaxel and rapamycin liposome and evaluate it for breast cancer efficacy both in vitro and in vivo. Results showed that a SPC/Chol/DSPE-PEG (2000) liposome was able to co-encapsulate paclitaxel and rapamycin with suitable encapsulation efficiency values, nanometric particle size, low polydispersity and neutral zeta potential. Taken together, FTIR and thermal analysis evidenced drug conversion to the more bioavailable molecular and amorphous forms, respectively, for paclitaxel and rapamycin. The pegylated liposome exhibited excellent colloidal stability and was able to retain drugs encapsulated, which were released in a slow and sustained fashion. Liposomes were more cytotoxic to 4T1 breast cancer cell line than the free drugs and drugs acted synergistically, particularly when co-loaded. Finally, in vivo therapeutic evaluation carried out in 4T1-tumor-bearing mice confirmed the in vitro results. The co-loaded paclitaxel/rapamycin pegylated liposome better controlled tumor growth compared to the solution. Therefore, we expect that the formulation developed herein might be a contribution for future studies focusing on the clinical combination of paclitaxel and rapamycin.

Ovarian cancer is the most lethal gynecological cancer of female reproductive system. In order to improve the survival rate, some modifications on nanoparticles surfaces have been investigated to promote active targeting of drugs into tumor microenvironment. The aim of this study was the development and characterization of folate-modified (PN-PCX-FA) and unmodified PLGA nanoparticles (PN-PCX) containing paclitaxel for ovarian cancer treatment. Nanocarriers were produced using nanoprecipitation technique and characterized by mean particle diameter (MPD), polydispersity index (PDI), zeta potential (ZP), encapsulation efficiency (EE), DSC, FTIR, in vitro cytotoxicity and cellular uptake. PN-PCX and PN-PCX-FA showed MPD 150 nm and PDI 0.2 with high EE (about 90%). Cytotoxicity assays in SKOV-3 cells demonstrated the ability of both formulations to cause cellular damage. PCX encapsulated in PN-PCX-FA at 1 nM showed higher cytotoxicity than PN-PCX. Folate-modified nanoparticles showed a 3.6-fold higher cellular uptake than unmodified nanoparticles. PN-PCX-FA is a promising system to improve safety and efficacy of ovarian cancer treatment. Further in vivo studies are necessary to prove PN-PCX-FA potential.

Objetivo: Este estudo transversal visa analisar comparativamente as prescrições de medicamentos provenientes da atenção básica tradicional (Unidades Básicas de Saúde - UBS) com as da Estratégia de Saúde da Família (ESF). Métodos: Foram incluídas 1053 prescrições, alocadas em dois grupos: 932 provenientes de UBS e 121 da ESF. Tais prescrições foram analisadas de acordo com a adequação aos itens legalmente exigidos e aos indicadores de qualidade (presença de antimicrobianos, presença de injetáveis, uso da denominação oficial, uso da relação de medicamentos essenciais, média de medicamentos prescritos). Resultados: As prescrições da ESF se mostraram estatisticamente mais completas quanto à presença do endereço do prescritor (82,6% UBS, 96,7% ESF), à ausência de rasuras (90,3% UBS, 96,7% ESF) e ao cumprimento dos aspectos legais exigidos referentes ao uso do medicamento, sendo eles: forma farmacêutica (70,7% UBS, 80,2% ESF), dose (70,9% UBS, 79,3% ESF), posologia (63,0% UBS, 75,2% ESF), via de administração (58,3% UBS, 83,5% ESF) e duração do tratamento (76,9% UBS, 92,6% ESF). Os resultados dos indicadores de qualidade da prescrição se aproximaram nos dois modelos de atenção básica e estão de acordo com os valores recomendados, com exceção da média de medicamentos prescritos, a qual evidenciou uma tendência à polifarmácia no município (3,9 medicamentos por prescrição na UBS e 3,5 na ESF). Conclusão: Apesar dos resultados revelarem práticas inapropriadas na prescrição de medicamentos na Atenção Primária como um todo, há evidências de que as prescrições da ESF estão mais próximas ao padrão ideal, o que pode favorecer o Uso Racional de Medicamentos.

Studies of in vitro release profiles are important during the development of drug delivery systems. This article describes the development and validation of a RP-HPLC method for the quantification of drug released from tamoxifen-loaded DSPE-PEG(2000)/TPGS micelles and the determination of the best dissolution medium and apparatus for this assay. The method showed specificity, linearity, precision, accuracy, and robustness for the parameters evaluated (range 0.25–20.0 µg mL−1). The best dissolution medium was 1.0 mol L−1 sodium salicylate, pH 7.4, and the most suitable apparatus was a PVC tube with one end covered with a dialysis membrane. This method was shown to be useful for tamoxifen quantification in in vitro release studies.

Antisense oligonucleotides (AS-ODNs) are short, single-stranded DNA molecules designed to bind specifically to a target messenger RNA (mRNA) and down-regulate gene expression. Despite being a promising class of therapeutics for a variety of diseases, they face major hurdles limiting their clinical application, including low intracellular delivery and poor in vivo stability. Among strategies available to enhance delivery, lipid nanoparticles have gained considerable attention. Active targeting of carriers of AS-ODNs is likely to further enhance delivery efficiency. For that, ligands for overexpressed receptors on the cell surface can be linked to the lipid nanoparticle, facilitating intracellular uptake, resulting in improved efficacy and reduced systemic toxicity. These include cell penetrating peptides (CPPs), transferrin, folate, oligosaccharides, polysaccharides and antibodies. Although targeted-lipid nanoparticles have been shown to enhance intracellular delivery and therapeutic effect of AS-ODNs, no clinical evaluation has been conducted yet. Therefore, more efforts are needed to turn these promising tools into clinical products.

Breast cancer is the second leading cause of cancer deaths among women. Paclitaxel (PTX) is used for its treatment, however non-selectivity, rapid systemic clearance and hypersensitivity to the commercially available formulation are major drawbacks. Rapamycin (RAP), an mTOR inhibitor, acts synergistically with PTX, and thus could be used in combination with it. Drug loading into nanocarriers, particularly liposomes, has proven to enhance efficacy and reduce side-effects of chemotherapeutic drugs. Within this context, the functionalization of liposomes with antibodies for overexpressed receptors on tumor surface is a potential strategy to increase specificity and reduce side-effects. Specifically, active targeting of HER2(+) breast cancer cells can be achieved by immunoliposomes consisting of liposomes coated with an anti-HER2 monoclonal antibody, Trastuzumab. Herein, we have synthesized PTX/RAP co-loaded immunoliposomes coated with Trastuzumab, performed physicochemical characterization, and evaluated the formulations for cytotoxicity and uptake in 4T1 (triple negative) and SKBR3 (HER2 positive) cell lines. Furthermore, we aimed to compare the immunoliposomes with liposomes and solution of PTX/RAP in vivo, employing human xenograft HER2-overexpressing tumors in mouse model. The co-loaded immunoliposomes had a mean particle size of 140.3nm, a zeta potential of -9.85mV and drug encapsulation efficiency of 55.87 and 69.51, respectively for PTX and RAP. The functionalization efficiency of Trastuzumab was higher than 70% and the antibody retained HER2 binding activity. Cell studies showed increased cytotoxicity of PTX/RAP for the immunoliposome, compared to the control liposomes in SKBR3 cells, which could be attributed to enhanced uptake mediated through HER2 binding. Furthermore, immunoliposomes were better able to control tumor growth in vivo, with tumor volume averages corresponding to 25.27, 44.38 and 47.78% of tumor volumes of untreated control, PTX/RAP solution and control liposomes, respectively. Taken together, our results support the clinical development of immunoliposomes for targeted delivery of PTX and RAP to HER2-positive breast cancer.

Background: Liposomes have been employed to improve pharmacokinetics and reduce side effects of drugs. They can be functionalized with antibodies for targeted delivery. While the monoclonal antibody trastuzumab has been employed in the therapy of HER2-positive breast cancer, the resistance developed during treatment has been reported. Rapamycin could be used in combination with trastuzumab for improved therapeutic response. Objective: In this study, we aimed to develop rapamycin-loaded liposomes and immunoliposomes with trastuzumab, characterize them and evaluate their in vitro cytotoxicity. Method: Formulations were prepared by the thin film hydration method and immunoliposome was conjugated to antibody by covalent bond. Characterization involved particle size, polydispersity, zeta potential, encapsulation efficiency, functionalization efficiency, DSC and FTIR assays. Cell studies were conducted through the MTT assay. Results: SPC:Chol:DSPE-PEG formulation prepared at 1:10 drug to lipid ratio presented high encapsulation efficiency, appropriate particle size, low polydispersity, negative zeta potential and colloidal stability. Rapamycin exhibited intermolecular interactions with lipids and underwent crystallinity reduction. Rapamycin-loaded immunoliposomes were prepared with high trastuzumab functionalization efficiency and antibody stability. Cytotoxicity studies showed that the HER2-positive SK-BR-3 cell line was sensitive to trastuzumab, either as free drug or in the context of immunoliposomes, and is more sensitive to rapamycin than the triple negative MDA-MB-231 cells. For MDA-MB-231, the liposomal rapamycin was more cytotoxic than the free drug. Furthermore, the immunoliposomes showed potent cytotoxicity against SK-BR-3 cells. Finally, rapamycin and trastuzumab exhibited in vitro synergistic effect, particularly through immunoliposomes. Conclusion: The formulation developed herein has potential for in vivo evaluation.

Ursolic acid is a molecule with several therapeutic applications not yet commercially explored because of its bioavailability-limiting water insolubility. To avoid this drawback, solid dispersions containing ursolic acid have been employed to increase water solubility. The influence of hydrophilic carriers, PEG 6000 and Poloxamer 407, and the method of preparation, fusion and solvent, were studied for ursolic acid in this work. The solid dispersions and physical mixtures were characterized by particle size, scanning electron microscopy, fourier transform infrared spectroscopy, X-ray diffractometry, differential scanning calorimetry, hot stage microscopy, water solubility and dissolution profile. Results showed that both methods and polymers used for solid dispersion preparation resulted in homogeneous powders, but the surfactant Poloxamer 407 enhanced the ursolic acid solubility in solid dispersions better than PEG 6000. With Poloxamer 407, both methods enabled complete dissolution of ursolic acid in phosphate buffer; however the solid dispersion showed higher solubility when prepared by the solvent method compared to the fusion method, 689.47 μg/mL and 328.52 μg/mL, respectively. For comparison, the physical mixture solubility was 248.17 μg/mL. The better results achieved with the solvent method were attributed to smaller particle size, amorphic conversion of ursolic acid from its less soluble crystalline state and hydrogen bond formation between drug and carrier, whereas there was a polymorphic change caused by the fusion method. Results indicated that the solid dispersion prepared by the solvent method is an adequate approach to increasing ursolic acid solubility and dissolution, a very important step toward the development of a pharmaceutical dosage form containing ursolic acid.

Poorly water soluble drugs tend to have low bioavailability, however, this can be improved by several methods. One of the most promising strategies is the employment of solid dispersions to increase water solubility and enhance oral bioavailability of these drugs. Nonetheless, the mechanisms of solid dispersion formation may influence the solid-state characteristics and thus the dissolution profile. In this study, rotary evaporation and spray-drying solvent evaporation techniques were used to produce solid dispersions of the anti-allergenic loratadine, a class II drug in the Biopharmaceutical Classification System, with the hydrophilic carrier polyvinylpyrrolidone K-30. Thermogravimetry, differential scanning calorimetry, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, particle size distribution by light scattering, solubility at different pHs, and dissolution profile experiments were carried out to evaluate the solid dispersions and physical mixtures. Results showed an increase in solubility, especially in acid medium, where the drug is protonated, and an enhancement in dissolution profiles, following first order kinetic, of solid dispersions manufactured by both the rotary evaporation and the spray-drying methods. Both methods proved to be equally adequate, when compared to physical mixtures. This is a consequence of particle size reduction, increased wettability due to intimate contact of the drug with the hydrophilic matrix, increased surface area, and the conversion of the crystalline to the amorphous state, which proved to be stable after 6 months at room temperature.

Albendazole sulfoxide (ABZSO), a broad spectrum anthelmintic drug extensively used in veterinary medicine, exhibits a low and erratic bioavailability due to its poor solubility in biological fluids. The aims of this study were the development, physicochemical characterization, and in vitro release profile evaluation of ABZSO-loaded Eudragit RS PO® microparticles (MPs) in order to improve the rate of dissolution and the dissolved percentage of the drug in pH 7.4. MPs were successfully obtained by the emulsification/solvent evaporation method, achieving entrapment efficiency and process yield of about 60% and mean size of 254 nm. The in vitro release profile study showed that dissolution of ABZSO followed a pseudo-second order kinetics and MPs were able to increase significantly ( p

Over a hundred years after the discovery of Chagas disease, this ailment continues to affect thousands of people. For more than 40 years, only two drugs have been available to treat it. Ursolic acid is a naturally occurring terpene that has shown a good trypanocidal action. However, the hydrophobicity of this compound presents a challenge for the development of proper delivery systems. Nanostructured systems are a prominent in delivering lipophilic drugs. Thus, a nanoemulsion containing ursolic acid was developed and had its trypanocidal activity and cytotoxicity evaluated. Pseudo-ternary phase diagrams and hydrophilic-lipophilic balance (HLB) system were used in the development. The system was stable throughout 90 days of testing, as evidenced by turbidimetry analysis and measurements of the droplet size (57.3 nm) and polydispersity index (0.24). Fourier transform infrared spectroscopy and mass spectrometry evidenced drug’s integrity in the formulation. An in vitro dissolution profile showed 75% of ursolic acid release after 5 min from the nanoemulsion into the alkaline dissolution medium, while only 20% could be released from a physical mixture after 2 h. Trypanocidal activity and cytotoxicity were evaluated on the CL Brener strain and LLC-MK2 (monkey kidney) fibroblast by chlorophenol red-β-d-galactoside (CPRG) method. Biological studies showed that the developed formulation was nontoxic and effective against replicant forms of the parasite. A stable and efficient nanoemulsion could be developed to improve the delivery of a promising drug to treat a threatening illness such as Chagas disease.

Despite affecting millions of people worldwide, Chagas disease is still neglected by the academia and industry and the therapeutic option available, benznidazole, presents limited efficacy and side effects. Within this context, ursolic acid may serve as an option for treatment, however has low bioavailability, which can be enhanced through the encapsulation in polymeric nanoparticles. Therefore, herein we developed ursolic acid-loaded nanoparticles with poly-e-caprolactone by the nanoprecipitation method and characterized them for particle size, zeta potential, polydispersity, encapsulation efficiency, morphology by scanning electron microscopy and thermal behavior by differential scanning calorimetry. Results indicated that an appropriate ratio of organic phase/aqueous phase and polymer/drug is necessary to produce smaller particles, with low polydispersity, negative zeta potential and high drug encapsulation efficiency. In vitro studies indicated the safety of the formulation against fibroblast culture and its efficacy in killing T. cruzi. Very importantly, the in vivo study revealed that the ursolic acid-loaded nanoparticle is as potent as the benznidazole group to control parasitemia, which could be attributed to improved bioavailability of the encapsulated drug. Finally, the toxicity evaluation showed that while benznidazole group caused liver toxicity, the nanoparticles were safe, indicating that this formulation is promising for future evaluation.

Liposomes have been employed to improve pharmacokinetics and reduce side effects of drugs. They can be functionalized with antibodies for targeted delivery. While the monoclonal antibody trastuzumab has been employed in the therapy of HER2-positive breast cancer, the resistance developed during treatment has been reported. Rapamycin could be used in combination with trastuzumab for improved therapeutic response.In this study, we aimed to develop rapamycin-loaded liposomes and immunoliposomes with trastuzumab, characterize them and evaluate their in vitro cytotoxicity.Formulations were prepared by the thin film hydration method and immunoliposome was conjugated to antibody by covalent bond. Characterization involved particle size, polydispersity, zeta potential, encapsulation efficiency, functionalization efficiency, DSC and FTIR assays. Cell studies were conducted through the MTT assay.SPC:Chol:DSPE-PEG formulation prepared at 1:10 drug to lipid ratio presented high encapsulation efficiency, appropriate particle size, low polydispersity, negative zeta potential and colloidal stability. Rapamycin exhibited intermolecular interactions with lipids and underwent crystallinity reduction. Rapamycin-loaded immunoliposomes were prepared with high trastuzumab functionalization efficiency and antibody stability. Cytotoxicity studies showed that the HER2-positive SK-BR-3 cell line was sensitive to trastuzumab, either as free drug or in the context of immunoliposomes, and is more sensitive to rapamycin than the triple negative MDA-MB-231 cells. For MDA-MB-231, the liposomal rapamycin was more cytotoxic than the free drug. Furthermore, the immunoliposomes showed potent cytotoxicity against SK-BR-3 cells. Finally, rapamycin and trastuzumab exhibited in vitro synergistic effect, particularly through immunoliposomes.The formulation developed herein has potential for in vivo evaluation.

siRNA has recently emerged as a potential therapeutic tool for the treatment of a variety of human diseases, such as viral infection, cancer, cardiovascular and inflammatory disorders. Briefly, siRNAs are double-stranded RNAs formed by 21-23 nucleotides that are able to bind to and trigger the degradation of specific target messenger RNAs (mRNAs) through the silencing induced by the RNA-induced silencing complex. Compared with conventional therapeutics, it affords high specificity, resulting in improved efficacy and decreased side effects. However, many hurdles hamper the effective clinical application, including low intracellular delivery and poor in vivo stability. These drawbacks can be improved by the use of drug delivery systems as non-viral carriers of siRNA, which present important advantages over viral carriers, particularly the lower immunogenicity. Lipid nanoparticles are the most commonly reported type of drug delivery system for siRNA. They consist of vesicular systems, with an inner aqueous cavity, where siRNA can be loaded, surrounded by a lipid bilayer. This chapter will focus on the efforts that have been carried out to deliver siRNA loaded in lipid nanoparticles, highlighting the advantages, disadvantages, applications, clinical relevance, and future perspectives.

Solid dispersions (SDs) are an approach to increasing the water solubility and bioavailability of lipophilic drugs such as ursolic acid (UA), a triterpenoid with trypanocidal activity. In this work, Gelucire 50/13, a surfactant compound with permeability-enhancing properties, and silicon dioxide, a drying adjuvant, were employed to produce SDs with UA. SDs and physical mixtures (PMs) in different drug/carrier ratios were characterized and compared using differential scanning calorimetry, hot stage microscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), particle size, water solubility values, and dissolution profiles. Moreover, LLC-MK2 fibroblast cytotoxicity and trypanocidal activity evaluation were performed to determine the potential of SD as a strategy to improve UA efficacy against Chagas disease. The results demonstrated the conversion of UA from the crystalline to the amorphous state through XRD. FTIR experiments provided evidence of intermolecular interactions among the drug and carriers through carbonyl peak broadening in the SDs. These findings helped explain the enhancement of water solubility from 75.98 μg/mL in PMs to 293.43 μg/mL in SDs and the faster drug release into aqueous media compared with pure UA or PMs, which was maintained after 6 months at room temperature. Importantly, improved SD dissolution was accompanied by higher UA activity against trypomastigote forms of Trypanosoma cruzi, but not against mammalian fibroblasts, enhancing the potential of UA for Chagas disease treatment.

Ursolic acid is a natural molecule that presents several pharmacological properties. In this work, an analytical method by RP-HPLC has been developed and validated for quantification of this drug in the solid dispersions, using PEG 6000 and Poloxamer 407 as polymers. The method was specific, linear in the range of 1.0-50.0 µg mL-1 (r

The aim of this study was to develop a formulation, containing the propolis standardized extract (EPP-AF®), which can assist in the healing of skin lesions. To achieve this objective the antimicrobial activity and chemical composition of the propolis extract was determined. The final product was subjected to in vitro and in vivo pre-clinical evaluation. The broth macrodilution method was used to determine the antimicrobial activity of the extracts and formulations against the microorganisms most commonly found in burns, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus and Staphylococcus epidermidis. Wistar rats with puncture wounded skin were used to evaluate the wound healing properties of propolis. The results of chemical and biological characterization demonstrated the batch-to-batch reproducibility of the standardized extract which is an unprecedented result. The antimicrobial and wound healing activity of the pharmaceutical studied showed the best results when samples contain 3.6% propolis, suggesting that this is the most promising composition.

A turbidimetric method has been used for quantification of fractionated heparin (FH) in pharmaceutical dosage. The UV detection at two wavelengths (290 and 500 nm) showed a significant increase in sensitivity of the method, specificity, and linearity to range 5.0-50.0 µg mL-1 and 50.0-200.0 µg mL-1, respectively (r < 0.99). At both wavelengths, the method was precise (inter-assay CV < 5.0%, and intra-assay CV < 3.0%), accurate (maximum deviation of ± 12%), and robust to the parameters evaluated. Turbidimetry proved to be easy, inexpensive and relatively fast. The results obtained attest to the reliability of the method.

Five laboratory experiments were performed to evaluate the effect of supplements of fatty acids and a green alga on the individual growth and reproduction of three species of tropical cladocerans Ceriodaphnia richardi, Daphnia ambigua, and D. gessneri feeding on natural seston from the Brazilian Lake Monte Alegre. Cohorts of newborns from cultivated females were submitted to one of the following treatments: (1) Natural seston, (2) Natural seston + microcapsules of EPA and DHA or linoleic and linolenic fatty acids, (3) Natural seston + oil-free microcapsules, and (4) Natural seston + green alga Scenedesmus spinosus (1 mg C l−1). Particulate organic carbon, algal carbon, C:P ratios of seston and green alga, polyunsaturated fatty acids (PUFA) content of seston and cladocerans, as well as phytoplankton composition, size, and shape were measured. The addition of fatty acids to seston did not significantly enhance growth and reproduction of the cladocerans, suggesting that sestonic PUFA content is sufficient for promoting cladoceran development, even in the cool–dry season when the fatty acids used in the experiments were 5–10 times lower in the seston than in the warm–wet season. Despite high C:P molar ratios in most experiments, there was only one indication of growth limitation by P. Reproduction was more affected than individual growth on some occasions by food quantity (energy) caused apparently by algal size, morphology, and digestion resistance. Energy availability, which is affected by algae morphological characteristics, seems to prevail over PUFA and P in controlling growth and reproduction of cladocerans in tropical Lake Monte Alegre.

Osmotically controlled and oral drug delivery systems utilize osmotic pressure for controlled delivery of active agent(s). Drug delivery from these systems, to a large extent, is independent of the physiological factors of the gastrointestinal tract and these systems can be utilized for systemic as well as targeted delivery of drugs. We apply the thermal methods and IR spectroscopy to study compatibility between atenolol and several excipients usually found in the osmotic systems formulations (Polyethylene oxide, MW 3350, 100000, 200000 and 5000000; HPMC K4000, magnesium stearate and cellulose acetate. Cellulose acetate, HPMC K4000 and magnesium stearate have essentially no interaction with atenolol otherwise all Polyethylene oxide excipients modifies significantly the drug melting point indicating some extend of interaction.