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1.
Mol Pharm ; 20(11): 5921-5936, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37874541

RESUMO

Prostate cancer (PCa) is the most prevalent cause of cancer deaths in men. Conventional strategies, such as surgery, radiation, or chemotherapy, face challenges including poor prognosis and resistance. Therefore, the development of new improved strategies is vital to enhance patient outcomes. Recently, immunotherapy has shown potential in the treatment of a range of cancers, including PCa. Tumor-associated macrophages (TAMs) play an important role in the tumor microenvironment (TME) and reprogramming of TAMs is associated with remodeling the TME. The colony-stimulating factor-1/colony stimulating factor-1 receptor (CSF-1/CSF-1R) signaling pathway is closely related to the polarization of TAMs. The downregulation of CSF-1R, using small interfering RNA (siRNA), has been shown to achieve the reprogramming of TAMs, from the immunosuppressive M2 phenotype to the immunostimulatory M1 one. To maximize specific cellular delivery an M2 macrophage-targeting peptide, M2pep, was formulated with an amphiphilic cationic ß-Cyclodextrin (CD) incorporating CSF-1R siRNA. The resulting nanoparticles (NPs) increased M2 macrophage targeting both in vitro and in vivo, promoting the release of M1 factors and simultaneously downregulating the levels of M2 factors through TAM reprogramming. The subsequent remodeling of the TME resulted in a reduction in tumor growth in a subcutaneous PCa mouse model mainly mediated through the recruitment of cytotoxic T cells. In summary, this M2pep-targeted CD-based delivery system demonstrated significant antitumor efficacy, thus presenting an alternative immunotherapeutic strategy for PCa treatment.


Assuntos
Ciclodextrinas , Nanopartículas , Neoplasias da Próstata , Masculino , Camundongos , Animais , Humanos , RNA Interferente Pequeno , Microambiente Tumoral , Neoplasias da Próstata/terapia , Neoplasias da Próstata/tratamento farmacológico , Imunoterapia/métodos
2.
Int J Mol Sci ; 23(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36077202

RESUMO

Non-viral delivery of therapeutic nucleic acids (NA), including siRNA, has potential in the treatment of diseases with high unmet clinical needs such as acute myeloid leukaemia (AML). While cationic biomaterials are frequently used to complex the nucleic acids into nanoparticles, attenuation of charge density is desirable to decrease in vivo toxicity. Here, an anionic amphiphilic CD was synthesised and the structure was confirmed by Fourier-transform infrared spectroscopy (FT-IR), Nuclear Magnetic Resonance (NMR), and high-resolution mass spectrometry (HRMS). A cationic amphiphilic cyclodextrin (CD) was initially used to complex the siRNA and then co-formulated with the anionic amphiphilic CD. Characterisation of the co-formulated NPs indicated a significant reduction in charge from 34 ± 7 mV to 24 ± 6 mV (p < 0.05) and polydispersity index 0.46 ± 0.1 to 0.16 ± 0.04 (p < 0.05), compared to the cationic CD NPs. Size was similar, 161−164 nm, for both formulations. FACS and confocal microscopy, using AML cells (HL-60), indicated a similar level of cellular uptake (60% after 6 h) followed by endosomal escape. The nano co-formulation significantly reduced the charge while maintaining gene silencing (21%). Results indicate that blending of anionic and cationic amphiphilic CDs can produce bespoke NPs with optimised physicochemical properties and potential for enhanced in vivo performance in cancer treatment.


Assuntos
Ciclodextrinas , Leucemia Mieloide Aguda , Nanopartículas , Ânions , Cátions , Ciclodextrinas/química , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Nanopartículas/química , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Mol Pharm ; 16(3): 1358-1366, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30721074

RESUMO

Functionalized cyclodextrin molecules assemble into a wide variety of superstructures in solution, which are of interest for drug delivery and other nanomaterial and biomaterial applications. Here we use a combined simulation and experimental approach to probe the coassembly of siRNA and cationic cyclodextrin (c-CD) derivatives into a highly stable gene delivery nanostructure. The c-CD form supramolecular structures via interdigitation of their aliphatic tails, analogous to the formation of lipid bilayers and micelles. The native conformation of siRNA is preserved by the encapsulating c-CD superstructure in an extensive hydrogen-bonding network between the positively charged side arms of c-CD and the negatively charged siRNA backbone. The stability of the complexation is confirmed using isothermal titration calorimetry, and the experimental/simulation codesign methodology opens new avenues for creation of highly engineerable gene delivery vectors.


Assuntos
Portadores de Fármacos/química , Composição de Medicamentos/métodos , Nanoestruturas/química , RNA Interferente Pequeno/química , beta-Ciclodextrinas/química , Calorimetria , Cátions/química , Estabilidade de Medicamentos , Técnicas de Transferência de Genes , Temperatura Alta , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular , Eletricidade Estática , Tensoativos/química
4.
Mol Pharm ; 14(1): 42-52, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-28043128

RESUMO

In recent years, RNA interference (RNAi) has emerged as a potential therapeutic offering the opportunity to treat a wide range of diseases, including prostate cancer. Modified cyclodextrins have emerged as effective gene delivery vectors in a range of disease models. The main objective of the current study was to formulate anisamide-targeted cyclodextrin nanoparticles to interact with the sigma receptor (overexpressed on the surface of prostate cancer cells). The inclusion of octaarginine in the nanoparticle optimized uptake and endosomal release of siRNA in two different prostate cancer cell lines (PC3 and DU145 cells). Resulting nanoparticles were less than 200 nm in size with a cationic surface charge (∼+20 mV). In sigma receptor-positive cell lines, the uptake of anisamide-targeted nanoparticles was reduced in the presence of the sigma receptor competitive ligand, haloperidol. When cells were transfected in 2D, the levels of PLK1 mRNA knockdown elicited by targeted versus untargeted nanoparticles tended to be greater but the differences were not statistically different. In contrast, when cells were grown on 3D scaffolds, recapitulating bone metastasis, targeted formulations showed significantly higher levels of PLK1 mRNA knockdown (46% for PC3 and 37% for DU145, p < 0.05). To our knowledge, this is the first time that a targeted cyclodextrin has been used to transfect prostate cancer cells in a 3D model of bone metastasis.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Ciclodextrinas/química , Ciclodextrinas/farmacologia , Inativação Gênica/efeitos dos fármacos , Nanopartículas/química , Metástase Neoplásica/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Cátions/metabolismo , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Técnicas de Transferência de Genes , Haloperidol/química , Haloperidol/farmacologia , Humanos , Masculino , Metástase Neoplásica/patologia , Tamanho da Partícula , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Interferência de RNA/efeitos dos fármacos , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Receptores sigma/metabolismo , Transfecção/métodos
5.
Sci Rep ; 14(1): 10008, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693282

RESUMO

Historically, investigators have not differentiated between patients with and without hemorrhagic transformation (HT) in large core ischemic stroke at risk for life-threatening mass effect (LTME) from cerebral edema. Our objective was to determine whether LTME occurs faster in those with HT compared to those without. We conducted a two-center retrospective study of patients with ≥ 1/2 MCA territory infarct between 2006 and 2021. We tested the association of time-to-LTME and HT subtype (parenchymal, petechial) using Cox regression, controlling for age, mean arterial pressure, glucose, tissue plasminogen activator, mechanical thrombectomy, National Institute of Health Stroke Scale, antiplatelets, anticoagulation, temperature, and stroke side. Secondary and exploratory outcomes included mass effect-related death, all-cause death, disposition, and decompressive hemicraniectomy. Of 840 patients, 358 (42.6%) had no HT, 403 (48.0%) patients had petechial HT, and 79 (9.4%) patients had parenchymal HT. LTME occurred in 317 (37.7%) and 100 (11.9%) had mass effect-related deaths. Parenchymal (HR 8.24, 95% CI 5.46-12.42, p < 0.01) and petechial HT (HR 2.47, 95% CI 1.92-3.17, p < 0.01) were significantly associated with time-to-LTME and mass effect-related death. Understanding different risk factors and sequelae of mass effect with and without HT is critical for informed clinical decisions.


Assuntos
Hospitalização , Infarto da Artéria Cerebral Média , Humanos , Feminino , Masculino , Idoso , Estudos Retrospectivos , Pessoa de Meia-Idade , Infarto da Artéria Cerebral Média/complicações , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/mortalidade , Hemorragia Cerebral/complicações , Edema Encefálico/etiologia , Fatores de Risco , AVC Isquêmico/mortalidade
6.
Eur J Pharm Sci ; 185: 106427, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36948408

RESUMO

Prostate cancer remains a serious condition threatening the health of men. Due to the complicated nature of the tumour microenvironment (TME), conventional treatments face challenges including poor prognosis and tumour resistance, therefore new therapeutic strategies are urgently needed. Small interfering RNA (siRNA), a double-stranded non-coding RNA, regulates specific gene expression through RNA interference. Tumour-associated macrophages (TAMs) are a potential therapeutic target in cancer immunotherapy. Colony stimulating factor-1/colony stimulating factor-1 receptor (CSF-1/CSF-1R) signaling pathway plays a crucial role in the polarization of the immunosuppressive TAMs, M2 macrophages. Downregulation of CSF-1R is known to reprogram the immunosuppressive TAMs, M2 macrophages, to the immunostimulatory phenotype, M1 macrophages. Sialic acid is a ligand for Siglec-1 (CD169) which is overexpressed on M2 macrophages with little expression in other phenotypes. Therefore, a sialic acid-targeted cyclodextrin-based nanoparticle was developed to specifically deliver CSF-1R siRNA to M2 macrophages. The nanoparticles were studied in vitro using both human and mouse prostate cancer cell lines. Results show that the targeted nanoparticles achieved cell specific delivery to M2 macrophages via the sialic acid-CD169 axis. The expression of CSF-1R was significantly downregulated in M2 macrophages (29.64% for targeted vs 19.31% for non-targeted nanoparticles in THP-1-derived M2 macrophages and 38.94% for targeted vs 18.51% for non-targeted nanoparticles in RAW 264.7-derived M2 macrophages, n = 4, p < 0.01). The resulting reprograming of M2 macrophages to M1 enhanced the level of apoptosis in the prostate cancer cells in a Transwell model (49.17% for targeted vs 37.68% for non-targeted nanoparticles in PC-3 cells and 69.15% for targeted vs 44.73% for non-targeted nanoparticles in TRAMP C1 cells, n = 3, p < 0.01). Thus, this targeted cyclodextrin-based siRNA drug delivery system provides a potential strategy for prostate cancer immunotherapy.


Assuntos
Ciclodextrinas , Nanopartículas , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Fatores Estimuladores de Colônias , Imunoterapia/métodos , Ácido N-Acetilneuramínico , Nanopartículas/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/terapia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/uso terapêutico , Microambiente Tumoral , Macrófagos Associados a Tumor , Receptor de Fator Estimulador de Colônias de Macrófagos/genética
7.
Pharmaceutics ; 15(2)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36839842

RESUMO

Huntington's disease (HD) is a progressive inherited neurodegenerative disease caused by a CAG repeat expansion in the huntingtin gene, which is translated into the pathologic mutant huntingtin (mHTT) protein. Despite the great potential of HTT lowering strategies and the numerous antisense oligonucleotides (ASOs) in pre- and clinical trials, sustained silencing of mHTT has not been achieved. As a strategy to improve ASO delivery, cyclodextrin-based nanoparticles (CDs) offer a promising approach. Here, three CDs with distinct chemical structures were designed and their efficacies were compared as potential platforms for the delivery of ASO targeting HTT. Results using striatal neurons and HD patient-derived fibroblasts indicate that modified γ-CDs exhibited the best uptake efficiency and successfully downregulated mHTT at protein and allele levels. The incorporation of the brain-targeting peptide RVG into the modified γ-CDs showed greater downregulation of mHTT protein and HD-causing allele SNP1 than untargeted ones in an in vitro blood-brain barrier model. Although the ASO sequence was designed as a nonallele-specific therapeutic approach, our strategy gives an additional benefit of some mHTT selectivity. Overall, this study demonstrated the CD platform's feasibility for delivering ASO-based therapeutics for HD treatment.

8.
Sleep ; 46(4)2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36255119

RESUMO

STUDY OBJECTIVES: Eye movement quantification in polysomnograms (PSG) is difficult and resource intensive. Automated eye movement detection would enable further study of eye movement patterns in normal and abnormal sleep, which could be clinically diagnostic of neurologic disorders, or used to monitor potential treatments. We trained a long short-term memory (LSTM) algorithm that can identify eye movement occurrence with high sensitivity and specificity. METHODS: We conducted a retrospective, single-center study using one-hour PSG samples from 47 patients 18-90 years of age. Team members manually identified and trained an LSTM algorithm to detect eye movement presence, direction, and speed. We performed a 5-fold cross validation and implemented a "fuzzy" evaluation method to account for misclassification in the preceding and subsequent 1-second of gold standard manually labeled eye movements. We assessed G-means, discrimination, sensitivity, and specificity. RESULTS: Overall, eye movements occurred in 9.4% of the analyzed EOG recording time from 47 patients. Eye movements were present 3.2% of N2 (lighter stages of sleep) time, 2.9% of N3 (deep sleep), and 19.8% of REM sleep. Our LSTM model had average sensitivity of 0.88 and specificity of 0.89 in 5-fold cross validation, which improved to 0.93 and 0.92 respectively using the fuzzy evaluation scheme. CONCLUSION: An automated algorithm can detect eye movements from EOG with excellent sensitivity and specificity. Noninvasive, automated eye movement detection has several potential clinical implications in improving sleep study stage classification and establishing normal eye movement distributions in healthy and unhealthy sleep, and in patients with and without brain injury.


Assuntos
Algoritmos , Movimentos Oculares , Humanos , Eletroculografia/métodos , Estudos Retrospectivos , Aprendizado de Máquina
9.
Eur J Pharm Biopharm ; 169: 309-318, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34793942

RESUMO

Huntington's disease (HD) is a neurodegenerative disorder caused by a mutation in the huntingtin (HTT) gene, leading to a toxic version of the HTT protein. There are currently no disease-modifying therapies available. In this scenario, gene-based treatments for HD aimed at lowering HTT levels have become one of the most promising emerging therapeutic options. To date, however, promising results have only been achieved following direct intrathecal or intracranial injections designed to circumvent the blood-brain barrier (BBB). Consequently, efforts to develop less invasive delivery platforms are highly desirable. Here, we described a novel delivery system based on modified cyclodextrin nanoparticles (CDs) loaded with small interfering RNAs (siRNAs) targeting HTT andcomplexed with the rabies virus glycoprotein(RVG), a BBB-shuttle peptide. Results using an in vitro BBB model, indicate the formulation successfully crosses the brain endothelial cells, releases the encapsulated siRNAs into the cytoplasm of neuronal cells, and mediates downregulation of HTT. In conclusion, the CD platform is a promising option for delivery of siRNA-based therapeutics for HD with wider potential to treat other diseases with a genetically validated target in the central nervous system.


Assuntos
Proteína Huntingtina/genética , Doença de Huntington/genética , Nanopartículas , RNA Interferente Pequeno/administração & dosagem , Animais , Barreira Hematoencefálica/metabolismo , Linhagem Celular , Ciclodextrinas/química , Regulação para Baixo/genética , Células Endoteliais/metabolismo , Inativação Gênica , Técnicas de Transferência de Genes , Terapia Genética/métodos , Glicoproteínas/química , Humanos , Fragmentos de Peptídeos/química , Ratos , Proteínas Virais/química
10.
Food Funct ; 9(6): 3500-3508, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29892770

RESUMO

Plant proteins are often characterized by low solubilities and impaired functionalities e.g. emulsifying properties. In products like milk substitutes, these protein properties are of great importance to ensure good product quality. In this study proteolytic enzymes were used as a tool to increase protein solubility and alter their properties gently. A plant-based milk substitute based on quinoa was produced and treated with different enzymes. One α-amylase and three commercial proteases were selected: Hitempase 2XP, Profix 100L, Bioprotease N100L, and Flavourzyme 1000L. The protein solubility of the samples was initially low with 48.02% and was improved with the increasing degree of hydrolysis up to a value of 75.82% for Profix. These results were supported by SDS-PAGE and circular dichroism analysis: especially Profix degraded the proteins extensively. Quality characteristics, such as foaming, and emulsifying properties were not influenced considerably by the protease treatment. The results of this study provide an in-depth understanding of the effects of different enzymes in a complex system of a plant-based milk substitute and contribute to the development of protein based products.


Assuntos
Amilases/química , Chenopodium quinoa/química , Substitutos do Leite/química , Peptídeo Hidrolases/química , Proteínas de Plantas/química , Biocatálise , Manipulação de Alimentos , Concentração de Íons de Hidrogênio , Hidrólise , Controle de Qualidade , Solubilidade
11.
J Pharm Sci ; 103(5): 1346-55, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24604260

RESUMO

Modified cyclodextrins (CDs) have shown great promise as non-viral gene and siRNA delivery vectors in a range of in vitro and in vivo studies. In the current study, structural and biophysical characterisation of selected CDs was carried out to enhance our understanding of their interaction with nucleic acids. The methods used for such characterisation were dynamic light scattering, zeta potential measurements and circular dichroism. Variations in the chemistries of individual CDs and in the type of formulation were shown to affect key properties of complexes such as size, surface charge and nucleic acid conformation. Furthermore, the effects of temperature and pH on the conformation of nucleic acids were investigated. pH studies were intended to mimic the conditions encountered by cationic complexes during endocytosis. Circular dichroism studies revealed that changes occurred in DNA and siRNA conformation upon complexation with CDs and when exposed to increasing temperature and decreasing pH. Overall, siRNA appeared to be more susceptible to conformational changes although complexation of siRNA with CDs tended to have a stabilising effect.


Assuntos
Ciclodextrinas/química , Ácidos Nucleicos/química , Biofísica , Dicroísmo Circular/métodos , Endocitose , Concentração de Íons de Hidrogênio , Conformação de Ácido Nucleico , Análise Espectral , Temperatura
12.
Atherosclerosis ; 216(1): 74-82, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21333993

RESUMO

OBJECTIVES: We examined the role of C-fms+ cells in response to vascular injury with a focus on the temporal and spatial platelet interactions, monocyte survival and proliferation within the evolving neointimal lesion and monocyte proliferation within the circulation and specified monocyte reservoir sites. Finally, we investigated the therapeutic effect of C-fms kinase inhibition (CFKI) on neointimal hyperplasia post vessel injury. METHODS AND RESULTS: We utilized murine carotid-wire injury, a transgenic C-fms reporting mouse model, confocal microscopy, shear-flow studies, specific C-fms signalling inhibition to determine the activation, mobilization and recruitment of C-fms+ monocytes in the context of early and late vessel remodelling. C-fms+ cells were recruited as early as 4h and accumulated over time in the neointima following injury. Monocyte interaction with platelet thrombus under flow and in vivo, in addition to monocyte mobilisation into the circulation post-injury was impaired by CFKI administration. Sustained inhibition of C-fms over 1-2 weeks abrogated the neointimal response but preserved re-endothelialisation post-injury. CONCLUSION: These data establish C-fms as a key regulator of the vascular response to injury and a potentially attractive therapeutic target in disease states where neointimal hyperplasia, monocyte activation and pathologic remodelling are prominent and endothelial homeostasis is desirable.


Assuntos
Artérias Carótidas/metabolismo , Lesões das Artérias Carótidas/metabolismo , Monócitos/metabolismo , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Túnica Íntima/metabolismo , Lesões do Sistema Vascular/metabolismo , Animais , Plaquetas/metabolismo , Antígeno CD11b/metabolismo , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/patologia , Lesões das Artérias Carótidas/tratamento farmacológico , Lesões das Artérias Carótidas/genética , Lesões das Artérias Carótidas/patologia , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Hemorreologia , Hiperplasia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Monócitos/efeitos dos fármacos , Monócitos/patologia , Adesividade Plaquetária , Inibidores de Proteínas Quinases/farmacologia , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Fatores de Tempo , Túnica Íntima/efeitos dos fármacos , Túnica Íntima/lesões , Túnica Íntima/patologia , Lesões do Sistema Vascular/tratamento farmacológico , Lesões do Sistema Vascular/genética , Lesões do Sistema Vascular/patologia
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