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1.
J Toxicol Environ Health A ; 87(5): 185-198, 2024 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-38073488

RESUMEN

Tellimagrandin-I (TL) and camptothin A (CA) are ellagitannins widely found in diverse plant species. Numerous studies demonstrated their significant biological activities, which include antitumor, antioxidant, and hepatoprotective properties. Despite this protective profile, the effects of TL and CA on DNA have not been comprehensively investigated. Thus, the aim of this study was to determine the mutagenic and antimutagenic effects attributed to TL and CA exposure on Salmonella enterica serovar Typhimurium strains using the Ames test. In addition, the cytotoxic and genotoxic effects were examined on human lymphocytes, employing both trypan blue exclusion and CometChip assay. The antigenotoxic effect was determined following TL and CA exposure in the presence of co-treatment with doxorubicin (DXR). Our results from the Ames test indicated that TL or CA did not display marked mutagenic activity. However, TL or CA demonstrated an ability to protect DNA against the damaging effects of the mutagens 4-nitroquinoline-1-oxide and sodium azide, thereby exhibiting antimutagenic properties. In relation to human lymphocytes, TL or CA did not induce significant cytotoxic or genotoxic actions on these cells. Further, these ellagitannins exhibited an ability to protect DNA from damage induced by DOX during co-treatment, indicating their potential beneficial usefulness as antigenotoxic agents. In conclusion, the protective effects of TL or CA against mutagens, coupled with their absence of genotoxic and cytotoxic effects on human lymphocytes, emphasize their potential therapeutic value in chemopreventive strategies.


Asunto(s)
Antimutagênicos , Salmonella enterica , Humanos , Salmonella typhimurium/genética , Salmonella enterica/genética , Taninos Hidrolizables/farmacología , Serogrupo , Pruebas de Mutagenicidad , Mutágenos/toxicidad , Antimutagênicos/farmacología , Extractos Vegetales/farmacología , Carcinógenos/farmacología , ADN/farmacología , Linfocitos
2.
J Anim Sci ; 1012023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37837391

RESUMEN

A total of 360 pigs (DNA 600 × 241, DNA; initially 11.9 ±â€…0.56 kg) were used in a 28-d trial to evaluate the effects of different bones and analytical methods on the assessment of bone mineralization response to dietary P, vitamin D, and phytase in nursery pigs. Pens of pigs (six pigs per pen) were randomized to six dietary treatments in a randomized complete block design with 10 pens per treatment. Dietary treatments were designed to create differences in bone mineralization and included: (1) 0.19% standardized total tract digestibility (STTD) P (deficient), (2) 0.33% STTD P (NRC [2012] requirement) using monocalcium phosphate, (3) 0.33% STTD P including 0.14% release from phytase (Ronozyme HiPhos 2700, DSM Nutritional Products, Parsippany, NJ), (4) 0.44% STTD P using monocalcium phosphate, phytase, and no vitamin D, (5) diet 4 with vitamin D (1,653 IU/kg), and (6) diet 5 with an additional 50 µg/kg of 25(OH)D3 (HyD, DSM Nutritional Products, Parsippany, NJ) estimated to provide an additional 2,000 IU/kg of vitamin D3. After 28 d on feed, eight pigs per treatment were euthanized for bone (metacarpal, 2nd rib, 10th rib, and fibula), blood, and urine analysis. The response to treatment for bone density and ash was dependent upon the bone analyzed (treatment × bone interaction for bone density, P = 0.044; non-defatted bone ash, P = 0.060; defatted bone ash, P = 0.068). Thus, the response related to dietary treatment differed depending on which bone (metacarpal, fibula, 2nd rib, or 10th rib) was measured. Pigs fed 0.19% STTD P had decreased (P < 0.05) bone density and ash (non-defatted and defatted) for all bones compared to 0.44% STTD P, with 0.33% STTD P generally intermediate or similar to 0.44% STTD P. Pigs fed 0.44% STTD P with no vitamin D had greater (P < 0.05) non-defatted fibula ash compared to all treatments other than 0.44% STTD P with added 25(OH)D3. Pigs fed diets with 0.44% STTD P had greater (P < 0.05) defatted second rib ash compared to pigs fed 0.19% STTD P or 0.33% STTD P with no phytase. In summary, bone density and ash responses varied depending on bone analyzed. Differences in bone density and ash in response to P and vitamin D were most apparent with fibulas and second ribs. There were apparent differences in the bone ash percentage between defatted and non-defatted bone. However, differences between the treatments remain consistent regardless of the analytic procedure. For histopathology, 10th ribs were more sensitive than 2nd ribs or fibulas for the detection of lesions.


Lameness is defined as impaired movement or deviation from normal gait. There are many factors that can contribute to lameness, including but not limited to: infectious disease, genetic and conformational anomaly, and toxicity that affects the bone, muscle, and nervous systems. Metabolic bone disease is another cause of lameness in swine production and can be caused by inappropriate levels of essential vitamins or minerals. To understand and evaluate bone mineralization, it is important to understand the differences in diagnostic results between different bones and analytical techniques. Historically, percentage bone ash has been used as one of the procedures to assess metabolic bone disease as it measures the level of bone mineralization; however, procedures and results vary depending on the methodology and type of bone measured. Differences in bone density and ash in response to dietary P and vitamin D were most apparent in the fibulas and second ribs. There were apparent differences in the percentage of bone ash between defatted and non-defatted bone; however, the differences between the treatments remain consistent regardless of the analytic procedure. For histopathology, 10th ribs were more sensitive than 2nd ribs or fibulas for detection of lesions associated with metabolic bone disease.


Asunto(s)
6-Fitasa , Fósforo Dietético , Porcinos , Animales , Fósforo Dietético/farmacología , Calcificación Fisiológica , 6-Fitasa/farmacología , Vitamina D/farmacología , Tracto Gastrointestinal , Dieta/veterinaria , Vitaminas/farmacología , ADN/farmacología , Fosfatos/farmacología , Alimentación Animal/análisis , Fósforo , Digestión
3.
J Toxicol Environ Health A ; 86(16): 543-556, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37340982

RESUMEN

Alternanthera littoralis P. Beauv is a plant native to Brazil that exhibits various beneficial activities including antioxidant, antibacterial, antifungal, antiprotozoal, anti-hyperalgesic, and anti-inflammatory properties. The aim of this study was to assess the impact of the ethanol extract of Alternanthera littoralis (EEAl) on reproductive outcomes, embryofetal development, and DNA integrity of pregnant female mice. Pregnant Swiss female mice were randomly assigned to three experimental groups (n = 10): controls were administered either 1% Tween 80 (vehicle), EEAl 100 mg/kg or EEAl 1000 mg/kg. Treatment was administered through gavage during the gestational period until day 18. On gestational days 16, 17, and 18, a peripheral blood sample from the tail vein was obtained for DNA integrity analysis (micronucleus test). After the last collection, animals were euthanized by cervical dislocation. Maternal organs and fetuses were collected, weighed, and subsequently analyzed. Reproductive outcome parameters were assessed by measurement of number of implants, live fetuses, and resorptions. Embryonic development was determined by adequacy of weight for gestational age as well as determination of external, visceral, and skeletal malformations. Data demonstrated that EEAl did not produce maternal toxicity at either dose associated with no marked alterations in any of the reproductive outcome parameters including implantation sites, live/dead fetuses ratio, fetal viability, post-implantation losses, resorptions, and resorption rate. However, EEAl 1000 group reduced embryofetal development by lowering placental weight. In addition, there was an increase in the frequency of external and skeletal malformations in the EEAl 1000 group, which could not be attributed to extract exposure as these values were within control levels. Based upon our findings, evidence indicates that the EEAl at the concentrations employed in our study may be considered safe for use during pregnancy and extracts of this plant show potential for development of phytomedicines to be used in pregnancy.


Asunto(s)
Anomalías Inducidas por Medicamentos , Placenta , Animales , Femenino , Ratones , Embarazo , ADN/farmacología , Etanol , Feto , Edad Gestacional , Reproducción
4.
Environ Toxicol Chem ; 42(6): 1266-1275, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36896658

RESUMEN

Effects of anthropogenic activities such as urbanization, population growth, and agriculture on water quality are major concerns particularly in low-income countries where water quality monitoring can be challenging. The purpose of the present study was to evaluate the cytogenotoxic potential of water from urban and rural Malagasy marshes, coupling a fish (Nile tilapia, Oreochromis niloticus) and a plant (Allium cepa) species as bioindicators. The fish and plants were exposed for 72 h to water sampled in the two locations investigated. Using the comet assay on fish erythrocytes, DNA strand breaks were assessed, while mitotic index and nucleolar alterations were estimated in cells of the plant root apex. Comet assays revealed significant DNA strand breaks to fish erythrocytes in both the marshes investigated while the mitotic index and nucleolar characteristics in the roots of A. cepa mainly highlighted potential cytotoxicity in the urban marsh. Our results demonstrate the advantages of coupling in vivo biological test systems to screen potential cytogenotoxicity of surface water in low-income countries where comprehensive data sets of aquatic contaminants are often lacking. Environ Toxicol Chem 2023;42:1266-1275. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Asunto(s)
Cíclidos , Humedales , Animales , Ensayo Cometa , Daño del ADN , Cebollas/genética , Raíces de Plantas , ADN/farmacología
5.
Int J Med Mushrooms ; 25(2): 55-66, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36749057

RESUMEN

In this study, pink oyster mushroom Pleurotus djamor was cultivated using wheat straw (WS), quinoa stalk (QS), and their mixtures (WS-QS (1:1)) as substrate and evaluated in terms of antimicrobial, antioxidant, cytotoxicity, and DNA protective effects. Gram-positive and Gram-negative pathogen bacteria (Bacillus subtilis, Proteus vulgaris, Streptococcus mutans, Salmonella typhi, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli), dermatophyte (Trichophyton sp.) and yeast (Candida tropicalis) were used in the study. It was found to be very active against all bacteria (except S. mutans and S. typhi), and dermatophyte when compared to the control groups (8.7-33.3 mm), but low against C. tropicalis. It was seen that the best total antioxidant assay (TAS) value was 2.05 mmol/L on WS-QS (1:1). Depend on, it was determined that the total oxidant assay (TOS) value (5.26 µmol/L) in the same compost was lower than the others, and also the scavenging effect of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) was higher on WS at 25 mg/mL (84.20%). The methanol extract on WS at a concentration of 400 µg/mL, significantly reduced the percentage of viability in the human breast cancer (MDA-MB-231) cell line (2.2%). The methanol extracts on WS and QS medium were found to inhibit DNA damage induced by UV radiation and H2O2 at a concentration of 25 mg/mL. These results showed that pink oyster mushroom has benefits such as antimicrobial, antioxidant, cytotoxic, and DNA protective effects.


Asunto(s)
Antiinfecciosos , Pleurotus , Humanos , Antioxidantes/farmacología , Pleurotus/química , Peróxido de Hidrógeno , Metanol/farmacología , Antiinfecciosos/farmacología , Bacterias Gramnegativas , ADN/farmacología
6.
Int J Mol Sci ; 23(23)2022 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-36499160

RESUMEN

Oxidative stress is associated with aging, cancers, and numerous metabolic and chronic disorders, and phenolic compounds are well known for their health-promoting role due to their free-radical scavenging activity. These phytochemicals could also exhibit pro-oxidant effects. Due to its bioactive phenolic secondary metabolites, Usnea barbata (L.) Weber ex. F.H. Wigg (U. barbata) displays anticancer and antioxidant activities and has been used as a phytomedicine for thousands of years. The present work aims to analyze the properties of U. barbata extract in canola oil (UBO). The UBO cytotoxicity on oral squamous cell carcinoma (OSCC) CLS-354 cell line and blood cell cultures was explored through complex flow cytometry analyses regarding apoptosis, reactive oxygen species (ROS) levels, the enzymatic activity of caspase 3/7, cell cycle, nuclear shrinkage (NS), autophagy (A), and synthesis of deoxyribonucleic acid (DNA). All these studies were concomitantly performed on canola oil (CNO) to evidence the interaction of lichen metabolites with the constituents of this green solvent used for extraction. The obtained data evidenced that UBO inhibited CLS-354 oral cancer cell proliferation through ROS generation (316.67 × 104), determining higher levels of nuclear shrinkage (40.12%), cell cycle arrest in G0/G1 (92.51%; G0 is the differentiation phase, while during G1 phase occurs preparation for cell division), DNA fragmentation (2.97%), and autophagy (62.98%) than in blood cells. At a substantially higher ROS level in blood cells (5250.00 × 104), the processes that lead to cell death-NS (30.05%), cell cycle arrest in G0/G1 (86.30%), DNA fragmentation (0.72%), and autophagy (39.37%)-are considerably lower than in CLS-354 oral cancer cells. Our work reveals the ROS-mediated anticancer potential of UBO through DNA damage and autophagy. Moreover, the present study suggests that UBO pharmacological potential could result from the synergism between lichen secondary metabolites and canola oil phytoconstituents.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Usnea , Humanos , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/metabolismo , Usnea/química , Usnea/metabolismo , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello , Aceite de Brassica napus/farmacología , Autofagia , Daño del ADN , Especies Reactivas de Oxígeno/metabolismo , Apoptosis , Extractos Vegetales/farmacología , Fenoles/farmacología , ADN/farmacología , Línea Celular Tumoral
7.
J Toxicol Environ Health A ; 85(23): 972-987, 2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36208226

RESUMEN

Cancer and infectious diseases are among the leading causes of death in the world. Despite the diverse array of treatments available, challenges posed by resistance, side effects, high costs, and inaccessibility persist. In the Solanaceae plant family, few studies with Vassobia breviflora species relating to biological activity are known, but promising results have emerged. The phytochemicals present in the ethyl acetate fraction were obtained using ESI-MS-QTOF, and the antioxidants assays 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radical capture (ABTS), plasma ferric reduction capacity (FRAP), and total antioxidant capacity (TAC). Cytotoxic activity was evaluated by MTT, Neutral Red, and lactate dehydrogenase (LDH) released. The production of reactive oxygen species, nitric oxide, and purinergic enzymes was also investigated. Antibacterial activity was measured through minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and antibiofilm activity, in addition to genotoxicity in plasmid DNA. Five major masses were identified D-glucopyranose II, allyl disulfide, γ-lactones, pharbilignoside, and one mass was not identified. V. breviflora exhibited relevant antioxidant and cytotoxic activity against the HeLa cell line and enhanced expression effect in modulation of purinergic signaling. Antibacterial activities in the assays in 7 ATCC strains and 8 multidrug-resistant clinical isolates were found. V. breviflora blocked biofilm formation in producing bacteria at the highest concentrations tested. However, there was no plasmid DNA cleavage at the concentrations tested. Data demonstrated that V. breviflora exhibited an antioxidant effect through several methods and proved to be a promising therapeutic alternative for use against tumor cells via purinergic signaling and multidrug-resistant microorganisms, presenting an anti-biofilm effect.


Asunto(s)
Antioxidantes , Solanaceae , Acetatos , Antibacterianos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Bacterias , ADN/farmacología , Células HeLa , Humanos , Lactato Deshidrogenasas , Lactonas/farmacología , Pruebas de Sensibilidad Microbiana , Rojo Neutro/farmacología , Óxido Nítrico , Extractos Vegetales/química , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno , Ácidos Sulfónicos
8.
Fitoterapia ; 161: 105232, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35690187

RESUMEN

To find more effective anticancer agents, a series of novel dehydroabietylamine (DA) derivatives were synthesized, focusing on C-ring nitro modifications and C-18 imide introduction. Their cytotoxic activities against human tumor cell line HeLa (cervix), MCF-7 (breast), A549 (lung), HepG2 (liver), and nonmalignant cell line HUVEC (umbilical vein) in vitro were screened. The C-18 imide heterocyclic compounds 1, 2, and C-ring 14-nitro substituted 14 exhibited moderate to good cytotoxic activities and significant selectivity towards malignant cell lines. More importantly, they were significantly less cytotoxic to nonmalignant cells (HUVEC) than the parent compound and positive control doxorubicin hydrochloride (DOX). Meantime the mechanism of cytotoxicity of DA derivatives was studied. Annexin V-FITC/PI double-staining analysis suggested that cytotoxicity of compounds 2 and 14 was associated with early apoptosis induction. The interaction between compounds and DNA (herring sperm DNA) was studied using absorption spectral analysis and ethidium bromide (EB) fluorescence displacement experiments, the results exhibited that the binding of the compound to DNA was in the intercalative mode. The structure-activity relationship discussion implied that introduction of the nitro-group, especially the 14-nitro group, can significantly improve the cytotoxicity of dehydroabietylimide compounds. The relatively high cytotoxicity and significant high selectivity of compounds 2 and 14 indicated that they were particularly noteworthy. NO released amounts indicated that the amounts of NO released by the compounds bearing nitro-group were quite well associated positive correlation with their cytotoxic activity, which provide a new strategy for structure design of DA anticancer agents in the future.


Asunto(s)
Antineoplásicos , Semen , Abietanos , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis , Línea Celular Tumoral , Proliferación Celular , ADN/farmacología , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Imidas/farmacología , Masculino , Estructura Molecular , Relación Estructura-Actividad
9.
Sci Adv ; 7(45): eabj0611, 2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34739313

RESUMEN

This work reports a suction-based cutaneous delivery method for in vivo DNA transfection. Following intradermal Mantoux injection of plasmid DNA in a rat model, a moderate negative pressure is applied to the injection site, a technique similar to Chinese báguàn and Middle Eastern hijama cupping therapies. Strong GFP expression was demonstrated with pEGFP-N1 plasmids where fluorescence was observed as early as 1 hour after dosing. Modeling indicates a strong correlation between focal strain/stress and expression patterns. The absence of visible and/or histological tissue injury contrasts with current in vivo transfection systems such as electroporation. Specific utility was demonstrated with a synthetic SARS-CoV-2 DNA vaccine, which generated host humoral immune response in rats with notable antibody production. This method enables an easy-to-use, cost-effective, and highly scalable platform for both laboratorial transfection needs and clinical applications for nucleic acid­based therapeutics and vaccines.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , ADN , SARS-CoV-2 , Piel/inmunología , Transfección , Vacunas de ADN , Administración Cutánea , Animales , COVID-19/genética , COVID-19/inmunología , COVID-19/prevención & control , Vacunas contra la COVID-19/genética , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/farmacología , ADN/genética , ADN/inmunología , ADN/farmacología , Masculino , Ratas , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Succión , Vacunas de ADN/genética , Vacunas de ADN/inmunología , Vacunas de ADN/farmacología
10.
Plant Sci ; 312: 111036, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34620440

RESUMEN

Like in mammals, the plant immune system has evolved to perceive damage. Damaged-associated molecular patterns (DAMPs) are endogenous signals generated in wounded or infected tissue after pathogen or insect attack. Although extracellular DNA (eDNA) is a DAMP signal that induces immune responses, plant responses after eDNA perception remain largely unknown. Here, we report that signaling defenses but not direct defense responses are induced after eDNA applications enhancing broad-range plant protection. A screening of defense signaling and hormone biosynthesis marker genes revealed that OXI1, CML37 and MPK3 are relevant eDNA-Induced Resistance markers (eDNA-IR). Additionally, we observed that eDNA from several Arabidopsis ecotypes and other phylogenetically distant plants such as citrus, bean and, more surprisingly, a monocotyledonous plant such as maize upregulates eDNA-IR marker genes. Using 3,3'-Diaminobenzidine (DAB) and aniline blue staining methods, we observed that H2O2 but not callose was strongly accumulated following self-eDNA treatments. Finally, eDNA resulted in effective induced resistance in Arabidopsis against the pathogens Hyaloperonospora arabidopsidis, Pseudomonas syringae, and Botrytis cinerea and against aphid infestation, reducing the number of nymphs and moving forms. Hence, the unspecificity of DNA origin and the wide range of insects to which eDNA can protect opens many questions about the mechanisms behind eDNA-IR.


Asunto(s)
Arabidopsis/genética , ADN/farmacología , Resistencia a la Enfermedad/genética , Resistencia a la Enfermedad/inmunología , Inmunidad de la Planta/genética , Transducción de Señal/genética , Zea mays/genética , Arabidopsis/inmunología , Arabidopsis/microbiología , Brassica/genética , Brassica/inmunología , Brassica/microbiología , Citrus/genética , Citrus/inmunología , Citrus/microbiología , Productos Agrícolas/genética , Productos Agrícolas/inmunología , Productos Agrícolas/microbiología , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Variación Genética , Genotipo , Phaseolus/genética , Phaseolus/inmunología , Phaseolus/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/microbiología , Solanum/genética , Solanum/inmunología , Solanum/microbiología , Spinacia oleracea/genética , Spinacia oleracea/inmunología , Spinacia oleracea/microbiología , Zea mays/inmunología , Zea mays/microbiología
11.
Bioorg Med Chem Lett ; 39: 127851, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33631371

RESUMEN

The use of DNA-encoded libraries (DELs) has increased greatly over the last decade, and today a majority of pharmaceutical companies employ the technology. The technology may be applied to most soluble and purified targets. However, standard DEL technology has limitations; some targets are challenging to purify, and it is not possible to directly screen for cellular or biochemical activity. Numerous creative methods have been reported to overcome these limitations and expand DEL target scope. Reported proof-of-concept experiments include DEL selections of cell surfaces, and inside of living cells. Additional alternatives include the construction and biochemical screening of one-bead-one-compound (OBOC) DELs using picoliter aqueous droplets or microfabricated wells as containers. In these cases, the small-molecule moiety of the library member is liberated from its DNA barcode, and able to interact freely with the desired target. Lastly, patent literature suggests the ability to conduct cellular functional screens using OBOC DELs.


Asunto(s)
ADN/farmacología , Desoxirribonucleasas/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Línea Celular , Desoxirribonucleasas/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Estructura Molecular , Bibliotecas de Moléculas Pequeñas/química
12.
Int J Mol Sci ; 19(8)2018 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-30110965

RESUMEN

Plasmonic nanoparticles for drug delivery have attracted increasing interest over the last few years. Their localized surface plasmon resonance causes photothermal effects on laser irradiation, which allows for delivering drugs in a spatio-temporally controlled manner. Here, we explore the use of gold nanoparticles (AuNP) as carriers for pDNA in combination with pulsed laser irradiation to induce endosomal escape, which is currently considered to be one of the major bottlenecks in macromolecular drug delivery on the intracellular level. In particular, we evaluate nanocomplexes composed of JetPEI (polyethylenimine)pDNA and 10 nm AuNP, which do not exhibit endosomal escape by themselves. After incubating HeLa cells with these complexes, we evaluated endosomal escape and transfection efficiency using low- and high-energy laser pulses. At low laser energy heat is produced by the nanocomplexes, while, at higher laser energy, explosive vapour nanobubbles (VNB) are formed. We investigated the ability of heat transfer and VNB formation to induce endosomal escape and we examine the integrity of pDNA cargo after inducing both photothermal effects. We conclude that JetPEI/pDNA/AuNP complexes are unable to induce meaningful transfection efficiencies because laser treatment causes either dysfunctionality of the cargo when VNB are formed or forms too small pores in the endosomal membrane to allow pDNA to escape in case of heating. We conclude that laser-induced VNB is the most suitable to induce effective pDNA endosomal escape, but a different nanocomplex structure will be required to keep the pDNA intact.


Asunto(s)
Endosomas/metabolismo , Oro , Hipertermia Inducida , Terapia por Luz de Baja Intensidad , Nanopartículas del Metal , Neoplasias/terapia , Polietileneimina , Transfección/métodos , ADN/genética , ADN/farmacología , Endosomas/genética , Endosomas/patología , Oro/química , Oro/farmacología , Células HeLa , Humanos , Nanopartículas del Metal/química , Nanopartículas del Metal/uso terapéutico , Neoplasias/genética , Neoplasias/metabolismo , Polietileneimina/química , Polietileneimina/farmacología
13.
São Paulo; s.n; s.n; nov. 2015. 193 p. tab, graf, ilus.
Tesis en Portugués | LILACS | ID: biblio-834077

RESUMEN

Com o início da fortificação de farinhas com ácido fólico (AF) no Brasil, a partir 2004, a população passou a estar exposta de modo compulsório a maiores quantidades desta vitamina. Sabe-se que o AF na sua forma sintética pode não ser completamente convertido para formas metabolicamente ativas, levando ao aparecimento de uma fração não metabolizada no organismo. Este fato é mais preocupante nos indivíduos que além da fortificação, fazem uso terapêutico dessa vitamina, como em pacientes com anemias hemolíticas (esferocitose hereditária (EH), ß-talassemia heterozigótica (ß-TH), entre outras). O objetivo desse estudo foi avaliar se as concentrações séricas de AF não metabolizado (UMFA) afetam a metilação global do DNA; a expressão de RNAm de genes da DHFR, MTHFR, interferon-γ, TNF-α e interleucina (IL)-8; e a citotoxicidade de células NK. Foram incluídos 27 pacientes com EH, 50 indivíduos com ß-talassemia heterozigótica (ß-TH) e 136 indivíduos saudáveis. Outros 30 indivíduos saudáveis foram incluídos num estudo de intervenção com 5mg/dia de AF durante 90 dias. Foram realizadas as análises de: ácido fólico sérico, eritrocitário e UMFA, vitamina B12, homocisteína total; expressões de RNAm dos genes de MTHFR, DHFR, IFN-γ, TNF-α e IL-8; citotoxicidade das células NK; metilação global do DNA e citocinas séricas IL6, IL-8, IL10, IFN-γ e TNF-α. Resultados: Os pacientes EH apresentaram maiores concentrações de AF (sérico, eritrocitário e UMFA) que seus controles, sendo que 55,5% (método microbiológico) e 74,1% (método LC-MS/MS) apresentaram concentrações suprafisiológicas da vitamina, e 74,1% apresentaram concentrações aumentadas de UMFA. No grupo ß-TH foi observado maiores concentrações de folato eritrocitário comparado ao controle e 22% dos indivíduos tinham concentrações suprafisiológicas de AF. No estudo de intervenção, após 45 e 90 dias de uso de AF as concentrações suprafisiológicas estavam presentes em 93,3% dos indivíduos e 100% deles apresentavam concentrações aumentadas de UMFA. Não foram observadas diferenças nas taxas de metilação global do DNA entre os grupos EH e ß-TH quando comparados aos seus controles e não foi verificada correlação entre metilação global e concentrações de UMFA. Tanto EH quanto ß-TH apresentaram maior expressão de RNAm de IL-8, quando comparados aos seus controles. No grupo de intervenção houve maior expressão de IL-8 após 45 dias de uso de AF quando comparado ao período pré-intervenção. Foi mostrada uma correlação inversa entre as concentrações de folato eritrocitário com o número de células NK no grupo EH e com a capacidade citotóxica das células NK no grupo total (EH + controle). No grupo intervenção foi observado menor número e menor capacidade citotóxica das células NK após 90 dias de uso de AF. Conclusões: O uso de AF 5mg/dia foi associado com aumento expressivo das concentrações de folato sérico, eritrocitário, UMFA, na expressão de RNAm de genes da citocina inflamatória IL-8 e redução do número e da citotoxicidade das células NK. Dessa forma, altas doses de AF podem resultar em alterações de componentes do sistema imune podendo prejudicar os mecanismos de vigilância celular das células NK. Os nossos achados sugerem que é importante o acompanhamento terapêutico dos pacientes que fazem uso de AF, especialmente aqueles indivíduos que fazem uso crônico desta vitamina por longo tempo, como os pacientes com anemias hemolíticas, mulheres que desejam engravidar e gestantes


With the beginning of the fortification of flour with folic acid (FA) in Brazil, since 2004, the population has been exposed compulsorily to larger amounts of this vitamin. It is known that FA in its synthetic form can not be completely converted to metabolically active forms, leading to the appearance of an unmetabolized fraction in the body. This fact is more worrying in subjects beyond fortification, make therapeutic use of this vitamin, such as patients with hemolytic anemia (hereditary spherocytosis (HS), ß-thalassemia heterozygotic (ß-TH), among others). The aim of this study was to evaluate if serum concentrations of unmetabolized FA (UMFA) affect the global DNA methylation; mRNA expression of DHFR, MTHFR, interferon-γ, TNF-α and interleukin (IL)-8 genes; and on cytotoxicity of NK cells. It was included 27 patients EH, 50 subjects ß-TH and 136 healthy subjects. Another 30 healthy subjects were included in an intervention study with 5 mg/FA daily during 90 days. Analyzes performed were: serum and erythrocyte folate, and UMFA, vitamin B12, tHcy; mRNA expression of MTHFR, DHFR, IFN-γ, TNF-α and IL-8 genes; cytotoxicity of NK cells; global DNA methylation and serum cytokines IL6, IL-8, IL10, IFN-γ and TNF-α. Results: EH patients presented higher FA concentrations (serum, erythrocytes and UMFA) than controls ones, and 55.5% (microbiologic method) and 74.1% (LC-MS/MS method) showed supraphysiologic concentrations of vitamin, and 74.1% presented increased concentrations of UMFA. In ß-TH group, it was observed higher erythrocyte folate concentrations compared with the control and 22% of subjects had supraphysiological concentrations of FA. In the intervention study, after 45 and 90 days of FA use, supraphysiological concentrations were present in 93.3% of subjects and 100% of them showed increased concentrations of UMFA. It was not observed differences in global methylation of DNA between EH and ß-TH groups when compared to their controls and it was not observed significant correlation between global DNA methylation and UMFA levels. Both EH and ß-TH showed higher mRNA expression of IL-8 gene, when compared to controls. In the intervention group, there was higher mRNA expression of IL-8 gene after 45 days of FA use when compared to pre-intervention period. It was demonstrated an inverse correlation between erythrocyte folate levels and the number of NK cells in EH group; and cytotoxic capacity of NK cells on total group (EH + control). In intervention group, it was observed fewer number and lower cytotoxic capacity of NK cells after 90 days of AF use. Conclusions: The use of AF 5mg daily was associated with a significant increase in serum and erythrocytes folate levels, accompanied by increase in UMFA levels, an increase in mRNA expression of IL-8 gene, and reduction of the number and the cytotoxicity capacity of NK cells. Thus, high doses of AF can result in modifications of the immune system components, which may damage the cell surveillance mechanisms of NK cells. Our findings suggest that is important the therapeutic follow up of patients that are using AF, especially those subjects with chronic use of this vitamin, such as patients with hemolytic anemia, women who wish to become pregnant and pregnant women


Asunto(s)
ADN/farmacología , ARN Mensajero/farmacología , Alimentos Fortificados , Harina/clasificación , Ácido Fólico/administración & dosificación , Citotoxicidad Celular Dependiente de Anticuerpos , Células Asesinas Naturales/clasificación , Hematología
14.
Drugs ; 75(7): 723-30, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25911184

RESUMEN

Despite the great success of anti-tumour necrosis factor-based therapies, the treatment of Crohn's disease (CD) and ulcerative colitis (UC) still remains a challenge for clinicians, as these drugs are not effective in all patients, their efficacy may wane with time, and their use can increase the risk of adverse events and be associated with the development of new immune-mediated diseases. Therefore, new therapeutic targets are currently being investigated both in pre-clinical studies and in clinical trials. Among the technologies used to build new therapeutic compounds, the antisense oligonucleotide (ASO) approach is slowly gaining space in the field of inflammatory bowel diseases (IBDs), and three ASOs have been investigated in clinical trials. Systemic administration of alicaforsen targeting intercellular adhesion molecule-1, a protein involved in the recruitment of leukocytes to inflamed intestine, was not effective in CD, even though the same compound was of benefit when given as an enema to UC patients. DIMS0150, targeting nuclear factor (NF) κB-p65, a transcription factor that promotes pro-inflammatory responses, was very promising in pre-clinical studies and is currently being tested in clinical trials. Oral mongersen, targeting Smad7, an intracellular protein that inhibits transforming growth factor (TGF)-ß1 activity, was safe and well tolerated by CD patients, and the results of a phase II clinical trial showed the efficacy of the drug in inducing clinical remission in patients with active disease. In this leading article, we review the rationale and the clinical data available regarding these three agents, and we discuss the challenge of using ASOs in IBD.


Asunto(s)
Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Oligonucleótidos Antisentido/farmacología , Oligonucleótidos Antisentido/uso terapéutico , Animales , Ensayos Clínicos como Asunto , ADN/farmacología , ADN/uso terapéutico , Humanos , Oligonucleótidos/farmacología , Oligonucleótidos/uso terapéutico , Oligonucleótidos Fosforotioatos/farmacología , Oligonucleótidos Fosforotioatos/uso terapéutico
15.
Crit Rev Oncol Hematol ; 94(1): 31-44, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25577571

RESUMEN

The adaptive immune system has been the main focus of immunological strategies in oncology with only more recent approaches targeting innate immunity. Endosomal toll-like receptors (TLR-7, TLR-9) activate innate immune responses by signaling damage-associated molecular patterns (DAMP) from decaying tumor cells. This has led to the development of DNA-based TLR-9 agonists, which induce antitumor activity through innate and subsequent adaptive immune responses. Early clinical trials with CpG-ODN as TLR-9 agonists were associated with unfavorable tolerability and narrow clinical efficacy, leading to failure in pivotal trials. dSLIM, the active ingredient of MGN1703, is a DNA-based, radically different molecular alternative to CpG-ODN, which results in genuine antitumor immunomodulation. Preclinical and clinical studies of MGN1703 have confirmed that this TLR-9 agonist has therapeutic potential in a variety of solid tumors, while long-term treatment with high doses was very well tolerated. A pivotal trial of first-line maintenance treatment with MGN1703 in patients with metastatic colorectal cancer is underway.


Asunto(s)
Antineoplásicos/farmacología , ADN/farmacología , Factores Inmunológicos/farmacología , Receptor Toll-Like 9/agonistas , Adyuvantes Inmunológicos , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Ensayos Clínicos como Asunto , ADN/química , ADN/uso terapéutico , Evaluación Preclínica de Medicamentos , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Humanos , Factores Inmunológicos/química , Factores Inmunológicos/uso terapéutico , Inmunomodulación/efectos de los fármacos , Inmunoterapia , Neoplasias/inmunología , Neoplasias/metabolismo , Neoplasias/terapia , Oligodesoxirribonucleótidos/inmunología , Oligodesoxirribonucleótidos/farmacología , Receptor Toll-Like 9/metabolismo , Resultado del Tratamiento
16.
Drug Deliv ; 22(6): 849-61, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24725027

RESUMEN

This study was aimed to develop and evaluate p53 polyplex-loaded enteric-coated calcium pectinate microbeads for oral gene delivery as an effective novel alternative for colorectal cancer therapy. Mutation in p53 is the key event in colorectal cancer (CRC) and an important target for the treatment of CRC through gene therapy. Polymethacrylates-based non-viral vectors were evaluated for their ability to complex, protect and transfect p53 (wt) into colon cancer cell line. Polyplexes were formulated by complexation of cationic polymer with anionic pDNA at different N/P ratios. p53 polyplex-loaded calcium pectinate (CP) microbeads were prepared by ionotropic gelation of pectin with calcium chloride and coated with Eudragit® S100. In vitro release studies showed that enteric-coated CP microbeads protected the release of p53 polyplex in upper GIT with less than 10% release. In-vitro cell line studies and in vivo studies in rat showed that polymethacrylate carrier could transfect the pDNA effectively. Results of in vivo gene expression study further confirmed the ability of enteric-coated calcium pectinate microbeads to deliver pDNA specifically to rat colon. Conclusively, enteric-coated calcium pectinate microbeads released p53 polyplex specifically in colon and could serve as an effective alternative for CRC therapy.


Asunto(s)
ADN/administración & dosificación , Portadores de Fármacos/química , Genes p53 , Microesferas , Plásmidos/administración & dosificación , Ácidos Polimetacrílicos/química , Administración Oral , Animales , Cloruro de Calcio/química , Línea Celular Tumoral , Química Farmacéutica , Neoplasias Colorrectales/tratamiento farmacológico , ADN/farmacología , Liberación de Fármacos , Terapia Genética , Pectinas/química , Plásmidos/farmacología , Ratas , Comprimidos Recubiertos , Tecnología Farmacéutica , Transfección/métodos
17.
J Phys Chem B ; 118(6): 1535-44, 2014 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-24467641

RESUMEN

We report a one-step process to functionalize superparamagnetic iron oxide nanoparticle (SPIO-NP) surfaces with a controlled number of oligonucleotides. For this study, we use a specific oligonucleotide targeting the signal transducer and activator of transcription 3 (STAT3), a key regulator of cell survival and proliferation. This oligonucleotide is self-complementary and can adopt a hairpin structure. It is labeled with the fluorescein amidite group at the 3'-end. The polyanionic DNA is electrostatically attracted onto the positively charged surface of the bare SPIO-NPs. During synthesis, the molar ratio between the oligonucleotides and nanoparticles was varied from 17.5 to 175. For particles with a mean diameter of 10 nm, a nanoparticle surface saturation is observed corresponding to 70 DNA strands per particle. The increase of DNA density per nanoparticle is correlated to a transition from the hairpin structure adsorbed horizontally on the nanoparticle surface to a vertically ordered surface packing assembly. An in vitro study on human colon carcinoma cell line SW480 shows that the kinetics of internalization and biological activity of the NPs seem to be dependent on the oligonucleotide density. Cell death and the kinetics of internalization are favored by a low density of oligonucleotides.


Asunto(s)
Fenómenos Químicos , ADN/química , ADN/metabolismo , Compuestos Férricos/química , Nanopartículas/química , Oligonucleótidos/química , Oligonucleótidos/metabolismo , Secuencia de Bases , Transporte Biológico , Línea Celular Tumoral , ADN/genética , ADN/farmacología , Estabilidad de Medicamentos , Humanos , Hidrodinámica , Oligonucleótidos/genética , Oligonucleótidos/farmacología , Propiedades de Superficie
18.
Nat Nanotechnol ; 7(6): 389-93, 2012 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-22659608

RESUMEN

Nanoparticles are used for delivering therapeutics into cells. However, size, shape, surface chemistry and the presentation of targeting ligands on the surface of nanoparticles can affect circulation half-life and biodistribution, cell-specific internalization, excretion, toxicity and efficacy. A variety of materials have been explored for delivering small interfering RNAs (siRNAs)--a therapeutic agent that suppresses the expression of targeted genes. However, conventional delivery nanoparticles such as liposomes and polymeric systems are heterogeneous in size, composition and surface chemistry, and this can lead to suboptimal performance, a lack of tissue specificity and potential toxicity. Here, we show that self-assembled DNA tetrahedral nanoparticles with a well-defined size can deliver siRNAs into cells and silence target genes in tumours. Monodisperse nanoparticles are prepared through the self-assembly of complementary DNA strands. Because the DNA strands are easily programmable, the size of the nanoparticles and the spatial orientation and density of cancer-targeting ligands (such as peptides and folate) on the nanoparticle surface can be controlled precisely. We show that at least three folate molecules per nanoparticle are required for optimal delivery of the siRNAs into cells and, gene silencing occurs only when the ligands are in the appropriate spatial orientation. In vivo, these nanoparticles showed a longer blood circulation time (t(1/2) ≈ 24.2 min) than the parent siRNA (t(1/2) ≈ 6 min).


Asunto(s)
ADN , Sistemas de Liberación de Medicamentos/métodos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Silenciador del Gen/efectos de los fármacos , Nanopartículas , Neoplasias Experimentales/tratamiento farmacológico , ARN Interferente Pequeño , Animales , ADN/química , ADN/genética , ADN/farmacología , Femenino , Ácido Fólico/química , Ácido Fólico/farmacología , Regulación Neoplásica de la Expresión Génica/genética , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Experimentales/genética , Neoplasias Experimentales/metabolismo , ARN Interferente Pequeño/química , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología
19.
J Med Food ; 15(7): 629-38, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22612294

RESUMEN

High levels of reactive oxygen species inflict oxidative damage on various cellular components that eventually culminate in a variety of diseases. This study investigated the cytoprotective effects of a nucleic acid-based health product (Squina [Hong Kong, China] DNA) against oxidative stress, particularly in neuronal cells. Adult female Sprague-Dawley rats were treated with Squina DNA, and changes in mitochondrial antioxidant status and functional capacity were assessed by the activities of antioxidant enzymes and ATP generation capacity in brain, heart ventricular, kidney, skeletal muscle, and liver tissues of control and Squina DNA-treated rats. The effects of Squina DNA pretreatment on brain/neuronal cell injury were investigated in a rat model of cerebral ischemia/reperfusion (I/R) injury and a neuroblastoma SH-SY5Y cell model of ß-amyloid (Aß) protein fragment 25-35-induced toxicity. Long-term Squina DNA treatment caused dose-dependent increases in mitochondrial antioxidant status and functional capacity in rat brain, heart ventricular, kidney, skeletal muscle, and liver tissues. Squina DNA pretreatment significantly prevented I/R injury in brain tissue. The cerebroprotection was associated with a reversal of I/R-induced impairment in mitochondrial antioxidant status and disruption in membrane integrity. Squina DNA ethanol extract also significantly inhibited the Aß-induced apoptosis in SH-SY5Y neuronal cells, as evidenced by less caspase 3 and caspase 9 activation as well as mitochondrial cytochrome c release in Aß-challenged cells. Squina DNA may enhance the resistance of tissues and cells to oxidative stress, particularly in pathological conditions such as stroke and aging-related neurodegenerative diseases.


Asunto(s)
Antioxidantes , Isquemia Encefálica/tratamiento farmacológico , Encéfalo/efectos de los fármacos , ADN/uso terapéutico , Mitocondrias/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Daño por Reperfusión/prevención & control , Péptidos beta-Amiloides , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Apoptosis/efectos de los fármacos , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Isquemia Encefálica/metabolismo , Caspasas/metabolismo , Línea Celular Tumoral , Citocromos c/metabolismo , ADN/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Ventrículos Cardíacos/efectos de los fármacos , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/fisiología , Membranas Mitocondriales/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Enfermedades Neurodegenerativas/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismo , Salmón , Accidente Cerebrovascular/tratamiento farmacológico
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