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The mortality and morbidity rates for prostate cancer have recently increased to alarming levels, rising higher than lung cancer. Due to a lack of drug targets and molecular probes, existing theranostic techniques are limited. Human LIN28A and its paralog LIN28B overexpression are associated with a number of tumors resulting in a remarkable increase in cancer aggression and poor prognoses. The current review aims to highlight recent work identifying the key roles of LIN28A and LIN28B in prostate cancer, and to instigate further preclinical and clinical research in this important area.
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Terapia de Alvo Molecular , Medicina de Precisão , Neoplasias da Próstata/terapia , Proteínas de Ligação a RNA/metabolismo , Humanos , Masculino , Neoplasias da Próstata/patologiaRESUMO
BACKGROUND: Overexpression of the RAN GTP (RAN) gene has been shown to be linked to metastatic activity of MDA-MB231 human breast cancer cells by increasing Ras/MEK/ERK and PI3K/Akt/mTORC1 signalling. The aim of this study was to investigate the potential of polymeric nanoparticles to deliver two novel shRNA sequences, targeted against the RAN gene, to MDA-MB231 cells grown in culture and to assess their effects in a range of biological assays. METHODS: Biodegradable PLGA nanoparticles, loaded with shRNA-1 and shRNA-4, were fabricated using a double emulsion solvent evaporation technique and characterised for size, zeta potential and polydispersity index before testing on the MDA-MB231 cell line in a range of assays including cell viability, migration, invasion and gene knock down. RESULTS: shRNA-loaded nanoparticles were successfully fabricated and delivered to MDA-MB231 cells in culture, where they effectively released their payload, causing a decrease in both cell invasion and cell migration by knocking down RAN gene expression. CONCLUSION: Results indicate the anti-RAN shRNA-loaded nanoparticles deliver and release biological payload to MDA-MB231 cells in culture. This works paves the way for further investigations into the possible use of anti-RAN shRNA-loaded NP formulations for the treatment of breast cancer in vivo.
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Portadores de Fármacos/química , Nanopartículas/química , Poliglactina 910/química , RNA Interferente Pequeno/genética , Neoplasias da Mama , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Composição de Medicamentos , Liberação Controlada de Fármacos , Feminino , Técnicas de Silenciamento de Genes , Técnicas de Transferência de Genes , Humanos , Tamanho da Partícula , RNA Interferente Pequeno/farmacologia , Propriedades de SuperfícieRESUMO
BACKGROUND: Inhibition of the nuclear factor kappa beta (NF-κß) pathway has been proposed as a therapeutic target due to its key role in the expression of pro-inflammatory genes, including pro-inflammatory cytokines, chemokines, and adhesion molecules. Caffeic acid phenethyl ester (CAPE) is a naturally occurring anti-inflammatory agent, found in propolis, and has been reported as a specific inhibitor of NF-κß. However, the impact of CAPE on levels of myeloperoxidases (MPO) and pro-inflammatory cytokines during inflammation is not clear. The aims of this study were to investigate the protective efficacy of CAPE in the mouse model of colitis and determine its effect on MPO activity, pro-inflammatory cytokines levels, and intestinal permeability. METHOD: Dextran sulphate sodium was administered in drinking water to induce colitis in C57/BL6 mice before treatment with intraperitoneal administration of CAPE (30 mg kg-1 day-1). Disease activity index (DAI) score, colon length and tissue histology levels of MPO, pro-inflammatory cytokines, and intestinal permeability were observed. RESULTS: CAPE-treated mice had lower DAI and tissue inflammation scores, with improved epithelial barrier protection and significant reduction in the level of MPO and pro-inflammatory cytokines. CONCLUSION: Our results show that CAPE is effective in suppressing inflammation-triggered MPO activity and pro-inflammatory cytokines production while enhancing epithelial barrier function in experimental colitis. Thus, we conclude that CAPE could be a potential therapeutic agent for further clinical investigations for treatment of inflammatory bowel diseases in humans.
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Ácidos Cafeicos/farmacologia , Colite Ulcerativa/tratamento farmacológico , Células Epiteliais/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Álcool Feniletílico/análogos & derivados , Substâncias Protetoras/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/metabolismo , Citocinas/metabolismo , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Feminino , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Álcool Feniletílico/farmacologiaRESUMO
CONTEXT: Size, encapsulation efficiency and stability affect the sustained release from nanoparticles containing protein-type drugs. OBJECTIVES: Insulin was used to evaluate effects of formulation parameters on minimizing diameter, maximizing encapsulation efficiency and preserving blood glucose control following intraperitoneal (IP) administration. METHODS: Homogenization or sonication was used to incorporate insulin into poly(D,L-lactic-co-glycolic acid) (PLGA) nanoparticles with increasing poly(ethylene glycol) (PEG) content. Effects of polymer type, insulin/polymer loading ratio and stabilizer in the internal aqueous phase on physicochemical characteristics of NP, in vitro release and stability of encapsulated insulin were investigated. Entrapment efficiency and release were assessed by radioimmunoassay and bicinconnic acid protein assay, and stability was evaluated using SDS-PAGE. Bioactivity of insulin was assessed in streptozotocin-induced, insulin-deficient Type I diabetic mice. RESULTS: Increasing polymeric PEG increased encapsulation efficiency, while the absence of internal stabilizer improved encapsulation and minimized burst release kinetics. Homogenization was shown to be superior to sonication, with NP fabricated from 10% PEG-PLGA having higher insulin encapsulation, lower burst release and better stability. Insulin-loaded NP maintained normoglycaemia for 24 h in diabetic mice following a single bolus, with no evidence of hypoglycemia. CONCLUSIONS: Insulin-loaded NP prepared from 10% PEG-PLGA possessed therapeutically useful encapsulation and release kinetics when delivered by the IP route.
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Preparações de Ação Retardada/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Ácido Láctico/química , Nanopartículas/química , Polietilenoglicóis/química , Ácido Poliglicólico/química , Animais , Emulsões/química , Hipoglicemiantes/uso terapêutico , Injeções Intraperitoneais , Insulina/uso terapêutico , Masculino , Camundongos , Copolímero de Ácido Poliláctico e Ácido PoliglicólicoRESUMO
STUDY OBJECTIVE: We test the hypothesis that anesthesia, measured as pain scores, induced by a novel topical anesthetic putty is non-inferior (margin=1.3) to that provided by conventional lidocaine infiltration for the repair of lacerations. METHODS: A randomized controlled trial was conducted in the emergency department (ED) of a local hospital. Participants were randomly allocated to receive either infiltration anesthesia or topical anesthetic putty as per the trial protocol. Pain scores were recorded 15 minutes after infiltration and 30 minutes after topical anesthetic putty application. Median pain scores were compared between groups. Wound evaluation scores were conducted after 7 to 10 days and adverse events were monitored for both groups of participants throughout the study. RESULTS: One hundred and ten participants were enrolled in the study, with 56 receiving infiltration and 54 receiving topical anesthetic putty. The median difference between the pain scores of the 2 groups was 0 (95% confidence interval -1 to 0). There were no substantial differences between the 2 groups in terms of either the wound evaluation scores or the incidence of adverse events. CONCLUSION: The novel topical anesthetic putty was not inferior to infiltration with lidocaine with respect to the pain experienced during suturing, and this putty is a feasible alternative to infiltration anesthesia of lacerations in the ED.
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Anestésicos Locais/administração & dosagem , Lacerações/terapia , Lidocaína/administração & dosagem , Manejo da Dor/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestésicos Locais/uso terapêutico , Feminino , Humanos , Lidocaína/uso terapêutico , Masculino , Pessoa de Meia-Idade , Medição da Dor , Resultado do Tratamento , Cicatrização/efeitos dos fármacos , Adulto JovemRESUMO
No bioadhesive patch-based system is currently marketed. This is despite an extensive number of literature reports on such systems detailing their advantages over conventional pressure sensitive adhesive-based patches in wet environments and describing successful delivery of a diverse array of drug substances. This lack of proprietary bioadhesive patches is largely due to the fact that such systems are exclusively water-based, meaning drying is difficult. In this paper we describe, for the first time, a novel multiple lamination method for production of bioadhesive patches. In contrast to patches produced using a conventional casting approach, which took 48 hours to dry, bioadhesive films prepared using the novel multiple lamination method were dried in 15 min and were folded into formed patches in a further 10 min. Patches prepared by both methods had comparable physicochemical properties. The multiple lamination method allowed supersaturation of 5-aminolevulinic acid to be achieved in formed patch matrices. However, drug release studies were unable to show an advantage for supersaturation with this particular drug, due to its water high solubility. The multiple lamination method allowed greater than 90% of incorporated nicotine to remain within formed patches, in contrast to the 48% achieved for patches prepared using a conventional casting approach. The procedure described here could readily be adapted for automation by industry. Due to the reduced time, energy and ensuing finance now required, this could lead to bioadhesive patch-based drug delivery systems becoming commercially viable. This would, in turn, mean that pathological conditions occurring in wet or moist areas of the body could now be routinely treated by prolonged site-specific drug delivery, as mediated by a commercially produced bioadhesive patch.
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Ácido Aminolevulínico/química , Sistemas de Liberação de Medicamentos , Modelos Moleculares , Nicotina/química , Agonistas Nicotínicos/química , Fármacos Fotossensibilizantes/química , Pele/química , Adesividade , Administração Cutânea , Ácido Aminolevulínico/administração & dosagem , Ácido Aminolevulínico/análise , Animais , Animais Recém-Nascidos , Fenômenos Químicos , Composição de Medicamentos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Fenômenos Mecânicos , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/análise , Controle de Qualidade , Solubilidade , Sus scrofa , Resistência à Tração , Adesivo Transdérmico , VolatilizaçãoRESUMO
Almost 80% of chronic wounds have a bacterial biofilm present. These wound biofilms are caused by a range of organisms and are often polymicrobial. Pseudomonas aeruginosa is one of the most common causative organisms in wound infections and readily forms biofilms in wounds. To coordinate this, P. aeruginosa uses a process known as quorum sensing. Structural homologues of the quorum sensing signalling molecules have been used to disrupt this communication and prevent biofilm formation by Pseudomonas. However, these compounds have not yet reached clinical use. Here, we report the production and characterisation of a lyophilised PVA aerogel for use in delivering furanones to wound biofilms. PVA aerogels successfully release a model antimicrobial and two naturally occurring furanones in an aqueous environment. Furanone loaded aerogels inhibited biofilm formation in P. aeruginosa by up to 98.80%. Further, furanone loaded aerogels successfully reduced total biomass of preformed biofilms. Treatment with a sotolon loaded aerogel yielded a 5.16 log reduction in viable biofilm bound cells in a novel model of chronic wound biofilm, equivalent to the current wound therapy Aquacel AG. These results highlight the potential utility of aerogels in drug delivery to infected wounds and supports the use of biofilm inhibitory compounds as wound therapeutics.
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Neuropsychiatric disorders that affect the central nervous system cause considerable pressures on the health care system and have a substantial economic burden on modern societies. The present treatments based on available drugs are mostly ineffective and often costly. The molecular process of neuropsychiatric disorders is closely connected to modifying the genetic structures inherited or caused by damage, toxic chemicals, and some current diseases. Gene therapy is presently an experimental concept for neurological disorders. Clinical applications endeavor to alleviate the symptoms, reduce disease progression, and repair defective genes. Implementing gene therapy in inherited and acquired neurological illnesses entails the integration of several scientific disciplines, including virology, neurology, neurosurgery, molecular genetics, and immunology. Genetic manipulation has the power to minimize or cure illness by inducing genetic alterations at endogenous loci. Gene therapy that involves treating the disease by deleting, silencing, or editing defective genes and delivering genetic material to produce therapeutic molecules has excellent potential as a novel approach for treating neuropsychiatric disorders. With the recent advances in gene selection and vector design quality in targeted treatments, gene therapy could be an effective approach. This review article will investigate and report the newest and the most critical molecules and factors in neuropsychiatric disorder gene therapy. Different genome editing techniques available will be evaluated, and the review will highlight preclinical research of genome editing for neuropsychiatric disorders while also evaluating current limitations and potential strategies to overcome genome editing advancements.
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Terapia Genética , Transtornos Mentais , Humanos , Transtornos Mentais/genética , Transtornos Mentais/terapiaRESUMO
The Signal Transducer and Activator of Transcription 3 (STAT3) protein is encoded on chromosome 17q21. The SH2 and the DNA binding domains are critical structural components of the protein, together with tyrosine and serine residues that initiate phosphorylation. STAT3 interacts with DNA directly and functions in cells as both a signal transducer and a transcription factor. Its cytoplasmic activation results in dimerisation and nuclear translocation, where it is involved in the transcription of a large number of target genes. STAT3 is hyperactive in cancer cells as a result of upstream STAT3 mutations or enhanced cytokine production in the tumour environment. The STAT3 signalling pathway promotes many hallmarks of carcinogenesis and metastasis, including enhanced cell proliferation and survival, as well as migration and invasion into the extracellular matrix. Recent investigations into novel STAT3-based therapies describe a range of innovative approaches, such as the use of novel oligonucleotide drugs. These limit STAT3 binding to its target genes by attaching to SH2 and DNA-binding domains. Yet, despite these significant steps in understanding the underpinning mechanisms, there are currently no therapeutic agents that addresses STAT3 signalling in a clinically relevant manner.
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Neoplasias , Fator de Transcrição STAT3 , Regulação da Expressão Gênica , Humanos , Neoplasias/genética , Fosforilação , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/fisiologiaRESUMO
Angiogenesis and metastasis play pivotal roles in the progression of cancer. We recently discovered that crocin, a dietary carotenoid derived from the Himalayan crocus, inhibited the growth of colon cancer cells. However, the exact role of crocin on the angiogenesis and metastasis in colorectal cancer remains unclear. In the present study, we demonstrated that crocin significantly reduces the viability of colon cancer cells (HT-29, Caco-2) and human umbilical vein endothelial cells (HUVEC), but was not toxic to human colon epithelial (HCEC) cells. Furthermore, pre-treatment of human carcinoma cells (HT-29 and Caco-2) with crocin inhibited cell migration, invasion, and angiogenesis in concentration -dependent manner. Further studies demonstrated that crocin inhibited TNF-α, NF-κB and VEGF pathways in colon carcinoma cell angiogenesis and metastasis. Crocin also inhibited cell migration, invasion, and tube formation in human umbilical vein endothelial cells (HUVEC) in a concentration -dependent manner. We also observed that crocin significantly reduced the secretion of VEGF and TNF-α induced activation of NF-kB by human colon carcinoma cells. In the absence of TNF-α, a concentration-dependent reduction in NF-kB was observed. Many of these observations were confirmed by in vivo angiogenesis models, which showed that crocin significantly reduced the progression of tumour growth. Collectively, these finding suggest that crocin inhibits angiogenesis and colorectal cancer cell metastasis by targeting NF-kB and blocking TNF-α/NF-κB/VEGF pathways.
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Carcinoma , Neoplasias do Colo , Células CACO-2 , Carotenoides/farmacologia , Neoplasias do Colo/tratamento farmacológico , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , NF-kappa B/metabolismo , Neovascularização Patológica/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The efficacy of chemotherapy depends on the tumor microenvironment. This microenvironment consists of a complex cellular network that can exert both stimulatory and inhibitory effects on tumor genesis. Given the increasing interest in the effectiveness of cannabis, cannabinoids have gained much attention as a potential chemotherapy drug. Cannabinoids are a group of marker compounds found in Cannabis sativa L., more commonly known as marijuana, a psychoactive drug used since ancient times for pain management. Although the anticancer potential of C. sativa, has been recognized previously, increased attention was generated after discovering the endocannabinoid system and the successful production of cannabinoid receptors. In vitro and in vivo studies on various tumor models have shown therapeutic efficiency by modifying the tumor microenvironment. However, despite extensive attention regarding potential therapeutic implications of cannabinoids, considerable clinical and preclinical analysis is needed to adequately define the physiological, pharmacological, and medicinal aspects of this range of compounds in various disorders covered in this review. This review summarizes the key literature surrounding the role of cannabinoids in the tumor microenvironment and their future promise in cancer treatment.
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Canabinoides , Cannabis , Neoplasias , Canabinoides/farmacologia , Canabinoides/uso terapêutico , Endocanabinoides , Humanos , Neoplasias/tratamento farmacológico , Receptores de Canabinoides , Microambiente TumoralRESUMO
A combination of light and ultrasound activation of two conventional photosensitising drugs, methylene blue and rose bengal, was shown to generate higher levels of reactive oxygen species (ROS) and lower LD50 values than either light or ultrasound activation alone.
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Morte Celular , Luz , Azul de Metileno/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Rosa Bengala/farmacologia , Som , Animais , Células CHO , Linhagem Celular Tumoral , Sobrevivência Celular , Cricetinae , Avaliação Pré-Clínica de Medicamentos , Dose Letal Mediana , Azul de Metileno/química , Oxirredução , Fármacos Fotossensibilizantes/química , Rosa Bengala/metabolismoRESUMO
The purpose of this review is to highlight recent scientific developments and provide an overview of virus self-assembly and viral particle dynamics. Viruses are organized supramolecular structures with distinct yet related features and functions. Plant viruses are extensively used in biotechnology, and virus-like particulate matter is generated by genetic modification. Both provide a material-based means for selective distribution and delivery of drug molecules. Through surface engineering of their capsids, virus-derived nanomaterials facilitate various potential applications for selective drug delivery. Viruses have significant implications in chemotherapy, gene transfer, vaccine production, immunotherapy and molecular imaging.
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Micro-organisms use quorum sensing (QS), a cell density-dependent process, to communicate. This QS mode of interchange leads to the production of a variety of virulence factors, co-ordination of complex bacterial behaviours, such as swarming motility, degradation of host tissue and biofilm formation. QS is implicated in numerous human infections and consequently researchers have sought ways of effectively inhibiting the process in pathogenic bacteria. Two decades ago, furanones were the first class of chemical compounds identified as Pseudomonas aeruginosa QS inhibitors (QSIs). P. aeruginosa is a ubiquitous organism, capable of causing a wide range of infections in humans, including eye and ear infections, wound infections and potentially fatal bacteraemia and thus novel treatments against this organism are greatly needed. This review provides a brief background on QS and the use of furanones as QSIs. Based on the effectiveness of action, both in vivo and in vitro, we will explore the use of furanones as potential antimicrobial therapeutics and conclude with open questions.
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Antibacterianos/administração & dosagem , Furanos/administração & dosagem , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Animais , Antibacterianos/química , Furanos/química , Humanos , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/fisiologiaRESUMO
Poly(lactic-co-glycolic acid) nanocapsules containing amphiphilic biosurfactant sophorolipids were formulated using a dispersion-based procedure. Di-block copolymers were used to vary peripheral poly(ethylene glycol) density, and variation in the oil core was used to achieve efficient encapsulation of the sophorolipid payload. Particulate size, zeta potential, encapsulation efficiency, release and stability were characterised. A glyceryl monocaprate core composition had the lowest particulate size, maximum encapsulation efficiency and optimum shelf-life stability compared to other formulations. This core composition was used to deliver sophorolipid to both in vitro and in vivo model tumour cell lines (CT26 murine colon carcinoma) and the effect of peripheral hydrophilicity was evaluated. Formulations with 10% poly(ethylene glycol) density achieved more than 80% reduction in cancer cell viability after 72 h and enhanced cellular uptake in CT26 cells. These formulations exhibited higher tumour accumulation and a longer blood circulation profile when compared to the non-poly(ethylene glycol)-containing nanocapsules. Animals treated with sophorolipid-loaded nanocapsules showed a tumour growth inhibition of 57% when compared to controls. An assessment of tumour mass within the same study cohort showed the biggest reduction when compared control and free drug-treated cohorts. This study shows that hydrophilic poly(lactic-co-glycolic acid) nanocapsules loaded with sophorolipids can address the poor intracellular delivery associated with these biosurfactants and is a promising approach for the treatment of colon neoplasia. Graphical abstract.
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Carcinoma , Neoplasias do Colo/tratamento farmacológico , Ácidos Oleicos , Poliglactina 910 , Animais , Carcinoma/tratamento farmacológico , Linhagem Celular Tumoral , Modelos Animais de Doenças , Camundongos , Ácidos Oleicos/administração & dosagem , Ácidos Oleicos/farmacologia , Tamanho da Partícula , PolietilenoglicóisRESUMO
BACKGROUND: Multidrug resistance (MDR) limits the beneficial outcomes of conventional breast cancer chemotherapy. Ras-related nuclear protein (Ran-GTP) plays a key role in these resistance mechanisms, assisting cancer cells to repair damage to DNA. Herein, we investigate the co-delivery of Ran-RCC1 inhibitory peptide (RAN-IP) and doxorubicin (DOX) to breast cancer cells using liposomal nanocarriers. RESEARCH DESIGN: A liposomal delivery system, co-encapsulating DOX, and RAN-IP, was prepared using a thin-film rehydration technique. Dual-loaded liposomes were optimized by systematic modification of formulation variables. Real-Time-Polymerase Chain Reaction was used to determine Ran-GTP mRNA expression. In vitro cell lines were used to evaluate the effect of loaded liposomes on the viability of breast and lung cancer cell lines. In vivo testing was performed on a murine Solid Ehrlich Carcinoma model. RESULTS: RAN-IP reversed the Ran-expression-mediated MDR by inhibiting the Ran DNA damage repair function. Co-administration of RAN-IP enhanced sensitivity of DOX in breast cancer cell lines. Finally, liposome-mediated co-delivery with RAN-IP improved the anti-tumor effect of DOX in tumor-bearing mice when compared to single therapy. CONCLUSIONS: This study is the first to show the simultaneous delivery of RAN-IP and DOX using liposomes can be synergistic with DOX and lead to tumor regression in vitro and in vivo.
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Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Peptídeos/administração & dosagem , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/química , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Feminino , Humanos , Lipossomos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Increased epithelial permeability is a key feature of IBD pathogenesis and it has been proposed that agents which promote barrier function may be of therapeutic benefit. We have previously reported the secondary bile acid, ursodeoxycholic acid (UDCA), to be protective in a mouse model of colonic inflammation and that its bacterial metabolism is required for its beneficial effects. The current study aimed to compare the effects of UDCA, LCA, and a non-metabolizable analog of UDCA, 6-methyl-UDCA (6-MUDCA), on colonic barrier function and mucosal inflammation in a mouse model of colonic inflammation. Bile acids were administered daily to C57Bl6 mice by intraperitoneal injection. Colonic inflammation, induced by addition of DSS (2.5%) to the drinking water, was measured as disease activity index (DAI) and histological score. Epithelial permeability and apoptosis were assessed by measuring FITC-dextran uptake and caspase-3 cleavage, respectively. Cecal bile acids were measured by HPLC-MS/MS. UDCA and LCA, but not 6-MUDCA, were protective against DSS-induced increases in epithelial permeability and colonic inflammation. Furthermore, UDCA and LCA inhibited colonic epithelial caspase-3 cleavage both in DSS-treated mice and in an in vitro model of cytokine-induced epithelial injury. HPLC-MS/MS analysis revealed UDCA administration to increase colonic LCA levels, whereas LCA administration did not alter UDCA levels. UDCA, and its primary metabolite, LCA, protect against intestinal inflammation in vivo, at least in part, by inhibition of epithelial apoptosis and promotion of barrier function. These data suggest that clinical trials of UDCA in IBD patients are warranted.
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Doenças Inflamatórias Intestinais/tratamento farmacológico , Mucosa Intestinal/efeitos dos fármacos , Ácido Litocólico/farmacologia , Substâncias Protetoras/farmacologia , Ácido Ursodesoxicólico/farmacologia , Animais , Apoptose/efeitos dos fármacos , Colagogos e Coleréticos/farmacologia , Detergentes/farmacologia , Modelos Animais de Doenças , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , PermeabilidadeRESUMO
Biofilms are a collective of multiple types of bacteria that develop on a variety of surfaces. Biofilm development results in heightened resistance to antibiotics. Quorum sensing plays an important role in biofilm development as it is one of the common communication mechanisms within cells, which balances and stabilizes the environment, when the amount of bacteria increases. Because of the important implications of the roles biofilms play in infectious diseases, it is crucial to investigate natural antibacterial agents that are able to regulate biofilm formation and development. Various studies have suggested that natural plant products have the potential to suppress bacterial growth and exhibit chemopreventive traits in the modulation of biofilm development. In this review, we discuss and collate potential antibiofilm drugs and biological molecules from natural sources, along with their underlying mechanisms of action. In addition, we also discuss the antibiofilm drugs that are currently under clinical trials and highlight their potential future uses.
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Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções/tratamento farmacológico , Extratos Vegetais/farmacologia , Antibacterianos/uso terapêutico , Biofilmes/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Humanos , Infecções/microbiologia , Extratos Vegetais/uso terapêutico , Percepção de Quorum/efeitos dos fármacosRESUMO
[This corrects the article DOI: 10.18632/oncotarget.26930.].
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This review details the antimicrobial applications of inorganic nanomaterials of mostly metallic form, and the augmentation of activity by surface conjugation of peptide ligands. The review is subdivided into three main sections, of which the first describes the antimicrobial activity of inorganic nanomaterials against gram-positive, gram-negative and multidrug-resistant bacterial strains. The second section highlights the range of antimicrobial peptides and the drug resistance strategies employed by bacterial species to counter lethality. The final part discusses the role of antimicrobial peptide-decorated inorganic nanomaterials in the fight against bacterial strains that show resistance. General strategies for the preparation of antimicrobial peptides and their conjugation to nanomaterials are discussed, emphasizing the use of elemental and metallic oxide nanomaterials. Importantly, the permeation of antimicrobial peptides through the bacterial membrane is shown to aid the delivery of nanomaterials into bacterial cells. By judicious use of targeting ligands, the nanomaterial becomes able to differentiate between bacterial and mammalian cells and, thus, reduce side effects. Moreover, peptide conjugation to the surface of a nanomaterial will alter surface chemistry in ways that lead to reduction in toxicity and improvements in biocompatibility.