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1.
J Pharm Sci ; 113(8): 2475-2483, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38754735

RESUMO

The nasal administration of therapeutic fluids and vaccines is used to treat allergic rhinitis, sinusitis, congestion, coronaviruses and even Alzheimer's disease. In the latter, the drug must reach the olfactory region, so it finds its way into the central nervous system. Effective administration techniques able to reach the olfactory region are challenging due to the tortuous anatomy of the nasal cavity, and are frequently evaluated in vitro using transparent anatomical models. Here, the liquid distribution inside a 3D printed human nasal cavity is quantified for model fluids resulting from the discharge of a 1-mL syringe with either a spray-generating nozzle, and a straight tip emitting a collimated fluid stream. Experiments using two model fluids with different viscosities suggest that a simple, correctly positioned straight tip attached to a syringe is able to efficiently deliver most of a therapeutic fluid in the human olfactory region in the side-laying position, avoiding the adoption of head-back and head-down positions that can be difficult for patients in the age range typical of Alzheimer's disease. Furthermore, we demonstrate by computer simulations that the conclusion is valid within a wide range of parameters.


Assuntos
Administração Intranasal , Simulação por Computador , Cavidade Nasal , Humanos , Administração Intranasal/métodos , Modelos Anatômicos , Impressão Tridimensional , Viscosidade , Sistemas de Liberação de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/instrumentação
2.
Int J Mol Sci ; 24(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37762080

RESUMO

Chagas disease is a neglected tropical disease caused by the protozoan Trypanosoma cruzi. Benznidazole and nifurtimox are the two approved drugs for their treatment, but both drugs present side effects and efficacy problems, especially in the chronic phase of this disease. Therefore, new molecules have been tested with promising results aiming for strategic targeting action against T. cruzi. Several studies involve in vitro screening, but a considerable number of in vivo studies describe drug bioavailability increment, drug stability, toxicity assessment, and mainly the efficacy of new drugs and formulations. In this context, new drug delivery systems, such as nanotechnology systems, have been developed for these purposes. Some nanocarriers are able to interact with the immune system of the vertebrate host, modulating the immune response to the elimination of pathogenic microorganisms. In this overview of nanotechnology-based delivery strategies for established and new antichagasic agents, different strategies, and limitations of a wide class of nanocarriers are explored, as new perspectives in the treatment and monitoring of Chagas disease.

3.
J Bone Oncol ; 34: 100431, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35517058

RESUMO

Patients with heavily pretreated, late-stage cancer and bone metastasis are usually poor candidates for further chemotherapy. Previously, we showed that association to lipid nanoparticles (LDE) drastically decreases the toxicity of anti-cancer drugs. Here, we tested the hypothesis that paclitaxel (PTX) carried in LDE could benefit end-of-life patients with painful bone metastases that had been previously treated with conventional PTX. Methods: Eighteen consecutive patients with late-stage cancer, 8 with breast, 5 with prostate and 5 with lung carcinoma, aged 59±9 years, were included in this study. All were receiving opioid medication. LDE-PTX was administered at 175 mg/m 2 every 3 weeks until disease progression. Clinical imaging examinations and serum biochemistry determinations were performed to monitor disease progression. Intensity of bone pain, use of opioid medications and occurrence of pathological bone fractures were also evaluated. Results: In total, 104 chemotherapy cycles were performed and none of the patients showed clinical and laboratorial toxicities or pathological bone fractures. In all patients, pain was reduced so as to allow substitution of non-opioid for opioid medication. Median progression-free survival (PFS) was four months (95% CI 2.4-5.5), but in five patients PFS was longer than 6 months. Conclusions: Absence of observable clinical and laboratorial toxicities from LDE-PTX treatment, improvement of bone pain and the possible effect on PFS in some patients, despite previous use of conventional PTX, suggest that LDEPTX merits further clinical investigation .

4.
Pharmaceutics ; 14(5)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35631546

RESUMO

Among respiratory infections, tuberculosis was the second deadliest infectious disease in 2020 behind COVID-19. Inhalable nanocarriers offer the possibility of actively targeting anti-tuberculosis drugs to the lungs, especially to alveolar macrophages (cellular reservoirs of the Mycobacterium tuberculosis). Our strategy was based on the development of a mannose-decorated micellar nanoformulation based in Soluplus® to co-encapsulate rifampicin and curcumin. The former is one of the most effective anti-tuberculosis first-line drugs, while curcumin has demonstrated potential anti-mycobacterial properties. Mannose-coated rifampicin (10 mg/mL)-curcumin (5 mg/mL)-loaded polymeric micelles (10% w/v) demonstrated excellent colloidal properties with micellar size ~108 ± 1 nm after freeze-drying, and they remain stable under dilution in simulated interstitial lung fluid. Drug-loaded polymeric micelles were suitable for drug delivery to the deep lung with lung accumulation, according to the in vitro nebulization studies and the in vivo biodistribution assays of radiolabeled (99mTc) polymeric micelles, respectively. Hence, the nanoformulation did not exhibit hemolytic potential. Interestingly, the addition of mannose significantly improved (5.2-fold) the microbicidal efficacy against Mycobacterium tuberculosis H37Rv of the drug-co-loaded systems in comparison with their counterpart mannose-free polymeric micelles. Thus, this novel inhaled nanoformulation has demonstrated its potential for active drug delivery in pulmonary tuberculosis therapy.

5.
Front Cell Infect Microbiol ; 12: 773405, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35174104

RESUMO

Carbapenem-resistant Klebsiella pneumoniae (CR-KP) represents an emerging threat to public health. CR-KP infections result in elevated morbidity and mortality. This fact, coupled with their global dissemination and increasingly limited number of therapeutic options, highlights the urgency of novel antimicrobials. Innovative strategies linking genome-wide interrogation with multi-layered metabolic data integration can accelerate the early steps of drug development, particularly target selection. Using the BioCyc ontology, we generated and manually refined a metabolic network for a CR-KP, K. pneumoniae Kp13. Converted into a reaction graph, we conducted topological-based analyses in this network to prioritize pathways exhibiting druggable features and fragile metabolic points likely exploitable to develop novel antimicrobials. Our results point to the aptness of previously recognized pathways, such as lipopolysaccharide and peptidoglycan synthesis, and casts light on the possibility of targeting less explored cellular functions. These functions include the production of lipoate, trehalose, glycine betaine, and flavin, as well as the salvaging of methionine. Energy metabolism pathways emerged as attractive targets in the context of carbapenem exposure, targeted either alone or in conjunction with current therapeutic options. These results prompt further experimental investigation aimed at controlling this highly relevant pathogen.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Klebsiella , Antibacterianos/uso terapêutico , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Humanos , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo
6.
Liver Int ; 42(2): 444-457, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34800352

RESUMO

BACKGROUND & AIMS: Reaching efficacious drug delivery to target cells/tissues represents a major obstacle in the current treatment of solid malignancies including hepatocellular carcinoma (HCC). In this study, we developed a pipeline to selective add complex-sugars to the aglycone 4-methylumbelliferone (4MU) to help their bioavailability and tumour cell intake. METHODS: The therapeutic efficacy of sugar-modified rutinosyl-4-methylumbelliferone (4MUR) and 4MU were compared in vitro and in an orthotopic HCC model established in fibrotic livers. The mechanistic bases of its selective target to liver tumour cells were evaluated by the interaction with asialoglycoprotein receptor (ASGPR), the mRNA expression of hyaluronan synthases (HAS2 or HAS3) and hyaluronan deposition. RESULTS: 4MUR showed a significant antiproliferative effect on liver tumoural cells as compared to non-tumoural cells in a dose-dependent manner. Further analysis showed that 4MUR is incorporated mostly into HCC cells by interaction with ASGPR, a receptor commonly overexpressed in HCC cells. 4MUR-treatment decreased the levels of HAS2 and HAS3 and the cytoplasmic deposition of hyaluronan. Moreover, 4MUR reduced CFSC-2G activation, hence reducing the fibrosis. In vivo efficacy showed that 4MUR treatment displayed a greater tumour growth inhibition and increased survival in comparison to 4MU. 4MUR administration was associated with a significant reduction of liver fibrosis without any signs of tissue damage. Further, 60% of 4MUR treated mice did not present macroscopically tumour mass post-treatment. CONCLUSION: Our results provide evidence that 4MUR may be used as an effective HCC therapy, without damaging non-tumoural cells or other organs, most probably due to the specific targeting.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Hialuronan Sintases , Himecromona/farmacologia , Himecromona/uso terapêutico , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Camundongos
7.
J Biomol Struct Dyn ; 40(19): 9214-9234, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33970798

RESUMO

The main-protease (Mpro) catalyzes a crucial step for the SARS-CoV-2 life cycle. The recent SARS-CoV-2 presents the main protease (MCoV2pro) with 12 mutations compared to SARS-CoV (MCoV1pro). Recent studies point out that these subtle differences lead to mobility variances at the active site loops with functional implications. We use metadynamics simulations and a sort of computational analysis to probe the dynamic, pharmacophoric and catalytic environment differences between the monomers of both enzymes. So, we verify how much intrinsic distinctions are preserved in the functional dimer of MCoV2pro, as well as its implications for ligand accessibility and optimized drug screening. We find a significantly higher accessibility to open binding conformers in the MCoV2pro monomer compared to MCoV1pro. A higher hydration propensity for the MCoV2pro S2 loop with the A46S substitution seems to exercise a key role. Quantum calculations suggest that the wider conformations for MCoV2pro are less catalytically active in the monomer. However, the statistics for contacts involving the N-finger suggest higher maintenance of this activity at the dimer. Docking analyses suggest that the ability to vary the active site width can be important to improve the access of the ligand to the active site in different ways. So, we carry out a multiconformational virtual screening with different ligand bases. The results point to the importance of taking into account the protein conformational multiplicity for new promissors anti MCoV2pro ligands. We hope these results will be useful in prospecting, repurposing and/or designing new anti SARS-CoV-2 drugs.Communicated by Ramaswamy H. Sarma.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Domínio Catalítico , Ligantes , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Proteínas não Estruturais Virais/química , Antivirais/farmacologia , Antivirais/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Cisteína Endopeptidases/química
8.
Pharmaceutics ; 13(11)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34834206

RESUMO

Glycyrrhizic acid and its hydrolyzed metabolite 18ß-glycyrrhetinic acid, obtained from the plant Glycyrrhiza glabra, have numerous pharmacological activities, such as anti-inflammatory, anti-ulcerative, antiallergic, immunomodulatory, antiviral, antitumor, hepatoprotective, and antioxidant effects, and others. In addition to the pharmacological activities, in the 1980s, an interaction and uptake of these molecules by the liver was verified, which was later confirmed by other studies through the discovery of specific receptors in the hepatocytes. The presence of these specific receptors in the liver led to vectorization and delivery of drugs, by the introduction of glycyrrhizic acid or glycyrrhetinic acid on the surface of nanosystems, for the treatment of liver diseases. This review describes experimental evidence of vectorization by conjugating glycyrrhizic acid or glycyrrhetinic acid to nanosystems and delivery of antitumor drugs for the treatment of liver cancer and also describes the techniques used to perform this conjugation. We have shown that due to the existence of specific receptors for these molecules, in addition to the targeting of nanosystems to hepatocytes, nanosystems having glycyrrhizic acid or glycyrrhetinic acid on their surface had the same therapeutic effect in a significantly lower dose compared to the free drug and unconjugated nanosystems, with consequent reduction of side effects and toxicity.

9.
J Pharm Sci ; 110(4): 1557-1571, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33450220

RESUMO

Acyclovir is an antiviral drug poorly absorbed in the gastrointestinal tract due to its hydrophilicity, with low oral bioavailability (~20%). Although acyclovir is prescribed in the management of herpes simplex encephalitis (HSE), the disease has a poor prognosis, particularly if the treatment is delayed, reaching mortality rates of 70% if left untreated. Thus, high acyclovir doses are administered by intravenous (IV) infusion, usually at a dosage of 10 mg kg-1 8-hourly in adults with normal renal function. However, the mortality related to HSE treated with acyclovir remains high (~20%) and permanent sequelae are commonly reported after 1 year (~50%). This review analyzed clinical trials following IV acyclovir administration. Novel insights aiming to improve drug bioavailability were reviewed, including acyclovir or its prodrugs, leading to the systemic distribution of the drug or drug targeting. Much research effort has been made to improve antiviral therapy, searching for delivery systems increasing acyclovir bioavailability by non-invasive pathways, such as oral and nasal pathways, or parenterally administered nanotechnology-based systems leading to drug targeting. Nanocarriers administered by non-invasive pathways represent feasible alternatives to treat HSE, even though not be industrially manufactured yet.


Assuntos
Encefalite por Herpes Simples , Herpes Simples , Pró-Fármacos , Aciclovir , Adulto , Antivirais/uso terapêutico , Encefalite por Herpes Simples/tratamento farmacológico , Herpes Simples/tratamento farmacológico , Humanos , Infusões Intravenosas , Pró-Fármacos/uso terapêutico
10.
Curr Med Chem ; 28(13): 2485-2520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32484100

RESUMO

Targeted therapy has been recently highlighted due to the reduction of side effects and improvement in overall efficacy and survival from different types of cancers. Considering the approval of many monoclonal antibodies in the last twenty years, cancer treatment can be accomplished by the combination of monoclonal antibodies and small molecule chemotherapeutics. Thus, strategies to combine both drugs in a single administration system are relevant in the clinic. In this context, two strategies are possible and will be further discussed in this review: antibody-drug conjugates (ADCs) and antibody-functionalized nanoparticles. First, it is important to better understand the possible molecular targets for cancer therapy, addressing different antigens that can selectively bind to antibodies. After selecting the best target, ADCs can be prepared by attaching a cytotoxic drug to an antibody able to target a cancer cell antigen. Briefly, an ADC will be formed by a monoclonal antibody (MAb), a cytotoxic molecule (cytotoxin) and a chemical linker. Usually, surface-exposed lysine or the thiol group of cysteine residues are used as anchor sites for linker-drug molecules. Another strategy that should be considered is antibody-functionalized nanoparticles. Basically, liposomes, polymeric and inorganic nanoparticles can be attached to specific antibodies for targeted therapy. Different conjugation strategies can be used, but nanoparticles coupling between maleimide and thiolated antibodies or activation with the addition of ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)/ N-hydroxysuccinimide (NHS) (1:5) and further addition of the antibody are some of the most used strategies. Herein, molecular targets and conjugation strategies will be presented and discussed to better understand the in vitro and in vivo applications presented. Also, the clinical development of ADCs and antibody-conjugated nanoparticles are addressed in the clinical development section. Finally, due to the innovation related to the targeted therapy, it is convenient to analyze the impact on patenting and technology. Information related to the temporal evolution of the number of patents, distribution of patent holders and also the number of patents related to cancer types are presented and discussed. Thus, our aim is to provide an overview of the recent developments in immunoconjugates for cancer targeting and highlight the most important aspects for clinical relevance and innovation.


Assuntos
Antineoplásicos , Imunoconjugados , Nanopartículas , Neoplasias , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Humanos , Imunoconjugados/uso terapêutico , Neoplasias/tratamento farmacológico
12.
Placenta ; 100: 75-80, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32862059

RESUMO

During the period of pregnancy, several processes and physiological adaptations occur in the body and metabolism of pregnant woman. These physiological adaptations in pregnant woman end up leading to a suppression in immune system favoring obstetric complications to the mother, fetus and placental tissue. An effective pharmacological therapy for these complications is still a challenge, since some drugs during pregnancy can have deleterious and teratogenic effects. An emerging alternative to pharmacological therapy during pregnancy is drugs encapsulated in nanoparticles (NP), recent area called nano-obstetrics. NP have the advantage of drug targeting and reduction of side effects. Then, maternal, placental or fetal uptake can be expected, depending on the characteristics of NP. Inorganic NP, crossing placental barrier effectively, but have several nanotoxicological effects. While organic NP appear to have a better targeting capacity and have few toxicological effects, but the studies are still scarce. Thus, in this review, were examined questions related to use and impact of physicochemical aspects of inorganic and organic NP during pregnancy.


Assuntos
Nanopartículas/uso terapêutico , Complicações na Gravidez/tratamento farmacológico , Feminino , Humanos , Nanomedicina , Gravidez
13.
World J Clin Oncol ; 11(3): 110-120, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32257842

RESUMO

Cancer constitutes the second leading cause of death globally and is considered to have been responsible for an estimated 9.6 million fatalities in 2018. Although treatments against gastrointestinal tumors have recently advanced, those interventions can only be applied to a minority of patients at the time of diagnosis. Therefore, new therapeutic options are necessary for advanced stages of the disease. Glycosylation of antitumor agents, has been found to improve pharmacokinetic parameters, reduce side effects, and expand drug half-life in comparison with the parent compounds. In addition, glycosylation of therapeutic agents has been proven to be an effective strategy for their targeting tumor tissue, thereby reducing the doses of the glycodrugs administered to patients. This review focusses on the effect of the targeting properties of glycosylated antitumor agents on gastrointestinal tumors.

14.
Int J Pharm ; 555: 36-48, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30448310

RESUMO

This study explored the transition of lamellar-type liquid crystal (LLC) to biocompatible oil-in-water nanoemulsions able to modify benznidazole (BNZ) release and target the drug to cells infected with the T. cruzi parasite. Three cosolvents (2methylpyrrolidone [NMP], polyethylene glycol [POL], and propylene glycol [PRO] were tested to induce the transition of anisotropic LLC systems to isotropic nanoemulsions. Mixtures of soy phosphatidylcholine with sodium oleate stabilized the dispersions of medium chain triglyceride in water. Rheological measurements, polarized microscopy, and small angle X-ray scattering demonstrated that there is a phase transition from LLC to desired nanoemulsions. These small and narrow droplet-sized nanocarriers exhibited some advantages and promising features, such as the enhanced BNZ aqueous solubility and slow drug release rate. In vitro cell biocompatibility of formulations was assessed in the Vero E6 and SiHa cell lines. Drug-loaded nanoemulsions inhibited the epimastigote growth of the T. cruzi parasite (IC50 0.208 ±â€¯0.052 µg mL-1) and reduced its infective life form trypomastigote (IC50 0.392 ±â€¯0.107 µg mL-1). The oil-in-water nanoemulsions were demonstrated as promising biocompatible liquid drug delivery systems capable of improving the BNZ trypanocidal activity for the treatment of Chagas disease.


Assuntos
Sistemas de Liberação de Medicamentos , Nitroimidazóis/administração & dosagem , Tripanossomicidas/administração & dosagem , Trypanosoma cruzi/efeitos dos fármacos , Animais , Linhagem Celular , Doença de Chagas/tratamento farmacológico , Química Farmacêutica/métodos , Chlorocebus aethiops , Preparações de Ação Retardada , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Emulsões , Humanos , Concentração Inibidora 50 , Cristais Líquidos , Nanoestruturas , Nitroimidazóis/química , Nitroimidazóis/farmacologia , Transição de Fase , Solubilidade , Solventes/química , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Células Vero
15.
J Cardiovasc Pharmacol Ther ; 23(6): 561-569, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29779420

RESUMO

In previous studies, it was demonstrated that lipid core nanoparticles (LDE) resemble the low-density lipoprotein structure and carrying the antiproliferative agent paclitaxel (PTX) strongly reduced atherosclerosis lesions induced in rabbits by cholesterol feeding. Currently, the aim was to verify whether combining LDE-PTX treatment with methotrexate (MTX) associated with LDE (LDE-MTX) could accelerate the atherosclerosis regression attained with single LDE-PTX treatment, after withdrawing the cholesterol feeding. Thirty-eight rabbits were fed 1% cholesterol chow for 8 weeks. Six of these rabbits were then euthanized for analyses of the aorta (controls). In the remaining rabbits, cholesterol feeding was withdrawn, and those 32 animals were allocated to 3 groups submitted to different 8-week intravenous treatments, all once/week: LDE-PTX (n = 10; 4 mg/kg), LDE-PTX + LDE-MTX (n = 11; 4 mg/kg), and LDE-alone (n = 11). Rabbits were then euthanized and aortas were excised for morphometric, immunohistochemical, and gene expression analyses. After cholesterol feeding withdrawal, in comparison with LDE-alone group, both LDE-PTX and LDE-PTX + LDE-MTX treatments had the ability to increase the regression of plaque areas: -49% in LDE-PTX and -59% for LDE-PTX + LDE-MTX. However, only LDE-PTX + LDE-MTX treatment elicited reduction in the intima area, estimated in -57%. Macrophage presence in aortic lesions was reduced 48% by LDE-PTX and 43% by LDE-PTX + LDE-MTX treatment. Matrix metalloproteinase 9 was reduced by either LDE-PTX (74%) or LDE-PTX + LDE-MTX (78%). Tumor necrosis factor α gene expression was reduced 65% by LDE-PTX and 79% by LDE-PTX + LDE-MTX. In conclusion, treatment with LDE-PTX indeed accelerated plaque reduction after cholesterol feeding; LDE-PTX + LDE-MTX further increased this effect, without any observed toxicity. These results pave the way for the use of combined chemotherapy to achieve stronger effects on aggravated, highly inflamed atherosclerotic lesions.


Assuntos
Aorta/efeitos dos fármacos , Doenças da Aorta/prevenção & controle , Aterosclerose/tratamento farmacológico , Fármacos Cardiovasculares/administração & dosagem , Colesterol na Dieta , Lipídeos/química , Metotrexato/administração & dosagem , Nanopartículas , Paclitaxel/administração & dosagem , Placa Aterosclerótica , Animais , Aorta/metabolismo , Aorta/patologia , Doenças da Aorta/sangue , Doenças da Aorta/patologia , Aterosclerose/sangue , Aterosclerose/patologia , Fármacos Cardiovasculares/química , Citocinas/metabolismo , Modelos Animais de Doenças , Composição de Medicamentos , Quimioterapia Combinada , Mediadores da Inflamação/metabolismo , Lipossomos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Metotrexato/química , Paclitaxel/química , Coelhos
16.
J Cell Biochem ; 119(2): 1273-1284, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28722178

RESUMO

Cyclin-Dependent Kinase 9 (CDK9) is part of a functional diverse group of enzymes responsible for cell cycle control and progression. It associates mainly with Cyclin T1 and forms the Positive Transcription Elongation Factor b (p-TEFb) complex responsible for regulation of transcription elongation and mRNA maturation. Recent studies have highlighted the importance of CDK9 in many relevant pathologic processes, like cancer, cardiovascular diseases, and viral replication. Herein we provide an overview of the different pathways in which CDK9 is directly and indirectly involved.


Assuntos
Doenças Cardiovasculares/metabolismo , Quinase 9 Dependente de Ciclina/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Viroses/metabolismo , Animais , Doenças Cardiovasculares/genética , Ciclina T/genética , Ciclina T/metabolismo , Quinase 9 Dependente de Ciclina/genética , Humanos , Proteínas de Neoplasias/genética , Neoplasias/genética , Fator B de Elongação Transcricional Positiva/genética , Fator B de Elongação Transcricional Positiva/metabolismo , Elongação da Transcrição Genética , Viroses/genética
17.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;51(3): 7090, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889042

RESUMO

Particles are usually polydispersed and size is an important feature for lipid-based drug delivery systems in order to optimize cell-particle interactions as to pharmacologic action and toxicity. Lipid nanoparticles (LDE) with composition similar to that of low-density lipoprotein carrying paclitaxel were shown to markedly reduce atherosclerosis lesions induced in rabbits by cholesterol feeding. The aim of this study was to test whether two LDE fractions, one with small (20-60 nm) and the other with large (60-100 nm) particles, had different actions on the atherosclerotic lesions. The two LDE-paclitaxel fractions, prepared by microfluidization, were separated by density gradient ultracentrifugation and injected (4 mg/body weight, intravenously once a week) into two groups of rabbits previously fed cholesterol for 4 weeks. A group of cholesterol-fed animals injected with saline solution was used as control to assess lesion reduction with treatment. After the treatment period, the animals were euthanized for analysis. After treatment, both the small and large nanoparticle preparations of LDE-paclitaxel had equally strong anti-atherosclerosis action. Both reduced lesion extension in the aorta by roughly 50%, decreased the intima width by 75% and the macrophage presence in the intima by 50%. The two preparations also showed similar toxicity profile. In conclusion, within the 20-100 nm range, size is apparently not an important feature regarding the LDE nanoparticle system and perhaps other solid lipid-based systems.


Assuntos
Animais , Masculino , Coelhos , Paclitaxel/administração & dosagem , Aterosclerose/tratamento farmacológico , Moduladores de Tubulina/administração & dosagem , Nanopartículas/administração & dosagem , Lipídeos/administração & dosagem , Lipoproteínas LDL/efeitos dos fármacos , Tamanho da Partícula , Quimioterapia Combinada
18.
Nanomaterials (Basel) ; 8(1)2017 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-29271920

RESUMO

Doxorubicin (Dox) clinical use is limited by dose-related cardiomyopathy, becoming more prevalent with increasing cumulative doses. Previously, we developed Dox-loaded lipid-core nanocapsules (Dox-LNC) and, in this study, we hypothesized that self-assembling and interfacial reactions could be used to obtain arginylglycylaspartic acid (RGD)-surface-functionalized-Dox-LNC, which could target tumoral cells overexpressing αvß3 integrin. Human breast adenocarcinoma cell line (MCF-7) and human glioblastoma astrocytoma (U87MG) expressing different levels of αvß3 integrin were studied. RGD-functionalized Dox-LNC were prepared with Dox at 100 and 500 mg·mL-1 (RGD-MCMN (Dox100) and RGD-MCMN (Dox500)). Blank formulation (RGD-MCMN) had z-average diameter of 162 ± 6 nm, polydispersity index of 0.11 ± 0.04, zeta potential of +13.2 ± 1.9 mV and (6.2 ± 1.1) × 1011 particles mL-1, while RGD-MCMN (Dox100) and RGD-MCMN (Dox500) showed respectively 146 ± 20 and 215 ± 25 nm, 0.10 ± 0.01 and 0.09 ± 0.03, +13.8 ± 2.3 and +16.4 ± 1.5 mV and (6.9 ± 0.6) × 1011 and (6.1 ± 1.0) × 1011 particles mL-1. RGD complexation was 7.73 × 104 molecules per nanocapsule and Dox loading were 1.51 × 104 and 7.64 × 104 molecules per nanocapsule, respectively. RGD-functionalized nanocapsules had an improved uptake capacity by U87MG cells. Pareto chart showed that the cell viability was mainly affected by the Dox concentration and the period of treatment in both MCF-7 and U87MG. The influence of RGD-functionalization on cell viability was a determinant factor exclusively to U87MG.

19.
Lipids ; 52(12): 991-998, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29094255

RESUMO

Lipid core nanoparticles (LDE) resembling LDL behave similarly to native LDL when injected in animals or subjects. In contact with plasma, LDE acquires apolipoproteins (apo) E, A-I and C and bind to LDL receptors. LDE can be used to explore LDL metabolism or as a vehicle of drugs directed against tumoral or atherosclerotic sites. The aim was to investigate in knockout (KO) and transgenic mice the plasma clearance and tissue uptake of LDE labeled with 3H-cholesteryl ether. LDE clearance was lower in LDLR KO and apoE KO mice than in wild type (WT) mice (p < 0.05). However, infusion of human apoE3 into the apoE KO mice increased LDE clearance. LDE clearance was higher in apoA-I KO than in WT. In apoA-I transgenic mice, LDE clearance was lower than in apoA-I KO and than in apoA-I KO infusion with human HDL. Infusion of human HDL into the apoA-I KO mice resulted in higher LDE clearance than in the apoA-I transgenic mice (p < 0.05). In apoA-I KO and apoA-I KO infused human HDL, the liver uptake was greater than in WT animals and apoA-I transgenic animals (p < 0.05). LDE clearance was lower in apoE/A-I KO than in WT. Infusion of human HDL increased LDE clearance in those double KO mice. No difference among the groups in LDE uptake by the tissues occurred. In conclusion, results support LDLR and apoE as the key players for LDE clearance, apoA-I also influences those processes.


Assuntos
Apolipoproteínas E/genética , Lipídeos/sangue , Receptores de LDL/genética , Animais , Linhagem Celular , Humanos , Lipoproteínas HDL/administração & dosagem , Camundongos , Camundongos Knockout , Camundongos Transgênicos
20.
Med Oncol ; 34(9): 151, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28756613

RESUMO

Ovarian cancer is often diagnosed at advanced stages, when poorly responsive to standard treatment. First-line treatment consists in schemes including cytoreductive surgery followed by adjuvant chemotherapy schemes with platinum and taxane derivatives. Second-line regimens are based on gemcitabine and liposomal doxorubicin. Third line is often not worthwhile because of the high toxicity with poor response to treatment. Previously, we showed that paclitaxel (PTX) carried in non-protein lipid core nanoparticles (LDE) resembling the chemical structure of LDL has remarkably reduced toxicity. Here, the hypothesis was tested whether PTX-LDE could safely benefit patients in third-line treatment setting. Fourteen women unresponsive to second-line chemotherapy for ovarian cancer, aged 61 ± 10 years, clinical stage IV and TqNqM1, were included. PTX-LDE was administered at 175 mg/m2, 3/3 week dose. Patients were submitted to clinical examinations before each chemotherapy cycle. Serum biochemistry and imaging examinations to monitor disease progression were performed. In total, 74 cycles of chemotherapy were done and, in all cycles, clinical or laboratorial toxicities were not observed. Median progression-free survival (PFS) was 3.0 months (95% CI 2.0-3.9). In four patients, PFS was >6 months and in 2 > 1 year. The unpreceded, striking absence of toxicity and consistently long PFS, compared to previous results, indicate that at least 4 among 14 patients had tumor arrest by the treatment and clear benefit of PTX-LDE at third-line setting. The absence of observable toxicity allows dose escalating to improve response to treatment, as perspective to be tested in the ensuing studies.


Assuntos
Carcinoma/tratamento farmacológico , Lipídeos/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Epitelial do Ovário , Quimioterapia Adjuvante/métodos , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Progressão da Doença , Intervalo Livre de Doença , Doxorrubicina/análogos & derivados , Doxorrubicina/uso terapêutico , Feminino , Humanos , Polietilenoglicóis/uso terapêutico , Gencitabina
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