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1.
AAPS PharmSciTech ; 22(3): 83, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33625602

RESUMEN

Griffithsin (GRFT) has shown potent anti-HIV activity, and it is being developed as a drug candidate for HIV prevention. Successful implementation requires thorough understanding of its preformulation characterization. In this work, preformulation assessments were conducted to characterize GRFT and identify its degradation pathways under selected conditions of temperature, light, pH, shear, ionic strength, and oxidation. Compatibility with vaginal fluid simulant, vaginal enzymes, Lactobacillus spp., and human cervicovaginal secretions was assessed. The purity, melting temperature, and HIV gp120-binding affinity of GRFT stored at 4°C and 25°C in phosphate-buffered saline (PBS) were assessed for 2 years. Chemical modifications were evaluated by intact mass analysis and peptide sequencing. Excised human ectocervical tissue permeability and localization of GRFT were evaluated. Our results demonstrated GRFT to be safe and stable under all the preformulation assessment conditions studied except oxidative stress. When GRFT was exposed to hydrogen peroxide or human cervicovaginal secretion, methionine 78 in the protein sequence underwent oxidation. GRFT did not permeate through human cervical tissue but adhered to the superficial epithelial tissue. The 2-year stability study revealed no significant change in GRFT's aggregation, degradation, melting temperature, or gp120-binding affinity despite a slow increase in oxidation over time. These studies elucidated desirable safety and bioactivity profile for GRFT, showing promise as a potential drug candidate for HIV prevention. However, susceptibility to oxidative degradation was identified. Effective protection of GRFT from oxidation is required for further development.


Asunto(s)
Fármacos Anti-VIH/síntesis química , Fármacos Anti-VIH/farmacocinética , Productos Biológicos/síntesis química , Productos Biológicos/farmacocinética , Composición de Medicamentos/métodos , Secuencia de Aminoácidos , Fármacos Anti-VIH/administración & dosificación , Productos Biológicos/administración & dosificación , Cuello del Útero/efectos de los fármacos , Cuello del Útero/metabolismo , Femenino , Infecciones por VIH/metabolismo , Infecciones por VIH/prevención & control , VIH-1/efectos de los fármacos , VIH-1/fisiología , Humanos , Técnicas de Cultivo de Órganos , Lectinas de Plantas/administración & dosificación , Lectinas de Plantas/síntesis química , Lectinas de Plantas/farmacocinética , Vagina/efectos de los fármacos , Vagina/metabolismo
2.
Exp Parasitol ; 218: 108004, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32961172

RESUMEN

Haemonchus contortus is a hematophagous parasite causing damage to the production of ruminant animals throughout the world. This study evaluated the in vitro effect of proteins from Moringa oleifera (WSMoL - Water Soluble M. oleifera Lectin and cMoL - coagulant M. oleifera Lectin) on the motility of infective larvae and adult male and female worms of H. contortus. The specific activity of total proteases and the morphology of the worms exposed to the lectins were observed. Both lectins inhibited motility of all parasite stages tested. WSMoL and cMoL at 500 µg mL-1 interfered in the motility of larvae. Values of 11.1% and 8.1% were the lowest motility indices of larvae with sheath, and 30.6% and 16.4% were the lowest motility indices of exsheathed larvae treated with WSMoL and cMoL, respectively. In 1 mg mL-1 solutions of WSMoL and of cMoL, the motility index of adult male worms was 23.3% (p < 0.001) and 20% (p < 0.001), while the motility index of adult female worms was 63.3% (p > 0.05) and 26.6% (p < 0.001), respectively. Greater proteolytic activity was detected in extracts obtained from adult worms, male and female, after incubation with the lectins. Morphological changes caused by the lectins were revealed by changes in the crests of the cuticle, in the longitudinal striations and at the vulva.


Asunto(s)
Haemonchus/efectos de los fármacos , Moringa oleifera/química , Lectinas de Plantas/farmacología , Semillas/química , Animales , Femenino , Haemonchus/enzimología , Haemonchus/fisiología , Haemonchus/ultraestructura , Larva/efectos de los fármacos , Masculino , Microscopía Electrónica de Rastreo , Movimiento/efectos de los fármacos , Péptido Hidrolasas/metabolismo , Lectinas de Plantas/administración & dosificación , Lectinas de Plantas/aislamiento & purificación
3.
Artículo en Inglés | MEDLINE | ID: mdl-31611356

RESUMEN

Griffithsin (Grft) is an antiviral lectin that has been shown to potently inhibit HIV-1 by binding high-mannose N-linked glycosylation sites on HIV-1 gp120. A key factor for Grft potency is glycosylation at N295 of gp120, which is directly adjacent to N332, a target glycan for an entire class of broadly neutralizing antibodies (bNAbs). Here, we unify previous work on the importance of other glycans to Grft potency against HIV-1 and Grft's role in mediating the conformational change of gp120 by mutating nearly every glycosylation site in gp120. In addition to a significant loss of Grft activity by the removal of glycosylation at N295, glycan absence at N332 or N448 was found to have moderate effects on Grft potency. Interestingly, in the absence of N295, Grft effectiveness could be improved by a mutation that results in the glycan at N448 shifting to N446, indicating that the importance of individual glycans may be related to their effect on glycosylation density. Grft's ability to alter the structure of gp120, exposing the CD4 binding site, correlated with the presence of glycosylation at N295 only in clade B strains, not clade C strains. We further demonstrate that Grft can rescue the activity of the bNAbs PGT121 and PGT126 in the event of a loss or a shift of glycosylation at N332, where the bNAbs suffer a drastic loss of potency. Despite targeting the same region, Grft in combination with PGT121 and PGT126 produced additive effects. This indicates that Grft could be an important combinational therapeutic.


Asunto(s)
Fármacos Anti-VIH/farmacología , Anticuerpos ampliamente neutralizantes/administración & dosificación , Anticuerpos Anti-VIH/administración & dosificación , Proteína gp120 de Envoltorio del VIH/metabolismo , VIH-1/efectos de los fármacos , Lectinas de Plantas/farmacología , Fármacos Anti-VIH/administración & dosificación , Sitios de Unión , Terapia Combinada , Farmacorresistencia Viral/genética , Glicosilación , Proteína gp120 de Envoltorio del VIH/química , Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/inmunología , Infecciones por VIH/terapia , Infecciones por VIH/virología , VIH-1/inmunología , VIH-1/metabolismo , Humanos , Técnicas In Vitro , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Lectinas de Plantas/administración & dosificación , Conformación Proteica/efectos de los fármacos
4.
Mol Genet Metab ; 123(2): 105-111, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29198892

RESUMEN

Mucopolysaccharidosis type I (MPS I) is a lysosomal disease resulting from deficiency in the α-L-iduronidase (IDUA) hydrolase and subsequent accumulation of glycosaminoglycan (GAG). Clinically, enzyme replacement therapy (ERT) with IDUA achieves negligible neurological benefits presumably due to blood-brain-barrier (BBB) limitations. To investigate the plant lectin ricin B chain (RTB) as a novel carrier for enzyme delivery to the brain, an IDUA:RTB fusion protein (IDUAL), produced in N. benthamiana leaves, was tested in a murine model of Hurler syndrome (MPS I). Affect mice (n=3 for each group) were intravenously injected with a single dose of IDUAL (0.58, 2 or 5.8mgIDUAequivalents/kg) and analyzed after 24h. IDUA activities in liver, kidney and spleen increased significantly, and liver GAG levels were significantly reduced in all three groups. Plasma IDUA levels for all treated groups were high at 1h after injection and decreased by 95% at 4h, indicating efficient distribution into tissues. For long-term evaluations, IDUAL (0.58 or 2mg/kg, 8 weekly injections) was intravenously injected into MPS I mice (n=12 for each group). Thirteen days after the 8th injection, significant IDUA activity was detected in the liver and spleen. GAG levels in tissues including the brain cortex and cerebellum were significantly reduced in treated animals. Treated MPS I mice also showed significant improvement in neurocognitive testing. ELISA results showed that while there was a significant antibody response against IDUAL and plant-derived IDUA, there was no significant antibody response to RTB. No major toxicity or adverse events were observed. Together, these results showed that infusion of IDUAL allowed for significant IDUA levels and GAG reduction in the brain and subsequent neurological benefits. This RTB-mediated delivery may have significant implications for therapeutic protein delivery impacting a broad spectrum of lysosomal, and potentially neurological diseases.


Asunto(s)
Enfermedades del Sistema Nervioso Central/terapia , Terapia de Reemplazo Enzimático , Iduronidasa/administración & dosificación , Lisosomas/enzimología , Mucopolisacaridosis I/terapia , Lectinas de Plantas/química , Animales , Enfermedades del Sistema Nervioso Central/enzimología , Modelos Animales de Enfermedad , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Iduronidasa/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mucopolisacaridosis I/enzimología , Lectinas de Plantas/administración & dosificación , Nicotiana/química
5.
Clin Exp Immunol ; 189(1): 21-35, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28268243

RESUMEN

Neovascularization and jeopardized immunity has been critically emphasized for the establishment of malignant progression. Lectins are the diverse class of carbohydrate interacting proteins, having great potential as immunopotentiating and anti-cancer agents. The present investigation sought to demonstrate the anti-proliferative activity of Dolichos lablab lectin (DLL) encompassing immunomodulatory attributes. DLL specific to glucose and mannose carbohydrate moieties has been purified to homogeneity from the common dietary legume D. lablab. Results elucidated that DLL agglutinated blood cells non-specifically and displayed striking mitogenicity to human and murine lymphocytes in vitro with interleukin (IL)-2 production. The DLL-conditioned medium exerted cytotoxicity towards malignant cells and neoangiogenesis in vitro. Similarly, in-vivo anti-tumour investigation of DLL elucidated the regressed proliferation of ascitic and solid tumour cells, which was paralleled with blockade of tumour neovasculature. DLL-treated mice showed an up-regulated immunoregulatory cytokine IL-2 in contrast to severely declined levels in control mice. Mechanistic validation revealed that DLL has abrogated the microvessel formation by weakening the proangiogenic signals, specifically nuclear factor kappa B (NF-κB), hypoxia inducible factor 1α (HIF-1 α), matrix metalloproteinase (MMP)-2 and 9 and vascular endothelial growth factor (VEGF) in malignant cells leading to tumour regression. In summary, it is evident that the dietary lectin DLL potentially dampens the malignant establishment by mitigating neoangiogenesis and immune shutdown. For the first time, to our knowledge, this study illustrates the critical role of DLL as an immunostimulatory and anti-angiogenic molecule in cancer therapeutics.


Asunto(s)
Mitógenos/farmacología , Neoplasias/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Lectinas de Plantas/administración & dosificación , Lectinas de Plantas/farmacología , Células A549 , Aglutinación , Animales , Aorta/efectos de los fármacos , Técnicas de Cultivo de Célula , Membrana Corioalantoides/efectos de los fármacos , Córnea/irrigación sanguínea , Córnea/efectos de los fármacos , Disacáridos , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inmunomodulación , Interleucina-2/metabolismo , Metaloproteinasa 3 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratones Endogámicos BALB C , Mitógenos/inmunología , Lectinas de Plantas/inmunología , Ratas , Ratas Wistar , Semillas/química , Factor A de Crecimiento Endotelial Vascular/metabolismo
6.
Tumour Biol ; 39(5): 1010428317701634, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28459216

RESUMEN

The accumulating evidences show that Abrus agglutinin, a plant lectin, displays a broad range of anticancer activity including cancer-specific induction of apoptosis; however, the underlying molecular mechanism of Abrus agglutinin-induced oral cancer stem cell elimination remains elusive. Our data documented that Abrus agglutinin effectively downregulated the CD44+ expression with the increased CD44- population in different oral cancer cells. After 24-h Abrus agglutinin treatment, FaDu cells were quantified for orosphere formation in ultra-low attachment plates and data showed that Abrus agglutinin inhibited the number and size of orosphere in a dose-dependent manner in FaDu cells. Furthermore, Abrus agglutinin hindered the plasticity of FaDu orospheres as supported by reduced sphere formation and downregulated the self-renewal property via inhibition of Wnt-ß-catenin signaling pathway. Introduction of LiCl, a glycogen synthase kinase 3ß inhibitor, rescued the Abrus agglutinin-stimulated inhibition of ß-catenin and phosphorylated glycogen synthase kinase 3ß in FaDu cell-derived orospheres confirming importance of Wnt signaling in Abrus agglutinin-mediated inhibition of stemness. In this connection, our data showed that Abrus agglutinin restrained proliferation and induced apoptosis in FaDu-derived cancer stem cells in dose-dependent manner. Moreover, western blot data demonstrated that Abrus agglutinin increased the Bax/Bcl-2 ratio with activation of poly(adenosine diphosphate-ribose) polymerase and caspase-3 favoring apoptosis induction in orospheres. Abrus agglutinin induced reactive oxygen species accumulation in orospheres and pretreatment of N-acetyl cysteine, and a reactive oxygen species scavenger inhibited Abrus agglutinin-mediated caspase-3 activity and ß-catenin expression indicating reactive oxygen species as a principal regulator of Wnt signaling and apoptosis. In conclusion, Abrus agglutinin has a potential role as an integrative therapeutic approach for combating oral cancer through targeting self-renewability of orospheres via reactive oxygen species-mediated apoptosis.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Autorrenovación de las Células/efectos de los fármacos , Neoplasias de la Boca/tratamiento farmacológico , Lectinas de Plantas/administración & dosificación , Animales , Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3 beta/genética , Humanos , Receptores de Hialuranos/genética , Cloruro de Litio/administración & dosificación , Ratones , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Células Madre Neoplásicas/efectos de los fármacos , Lectinas de Plantas/química , Especies Reactivas de Oxígeno/metabolismo , Vía de Señalización Wnt/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Cancer Sci ; 107(1): 53-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26495901

RESUMEN

Bauhinia purprea agglutinin (BPA) is a well-known lectin that recognizes galactosyl glycoproteins and glycolipids. In the present study, we firstly found that BPA bound to human prostate cancer specimens but not to normal prostate ones. Therefore, we sought to develop BPA-PEG-modified liposomes (BPA-PEG-LP) encapsulating anticancer drugs for the treatment of prostate cancer. We examined the tumor targetability of BPA-PEG-LP with human prostate cancer DU145 cells, and observed that fluorescently labeled BPA-PEG-LP dominantly associated with the cells via the interaction between liposome-surface BPA and cell-surface galactosyl molecules. We also observed that BPA-PEG-LP accumulated in the prostate cancer tissue after the i.v. injection to DU145 solid cancer-bearing mice, and strongly bound to the cancer cells. In a therapeutic study, DU145 solid cancer-bearing mice were i.v. injected thrice with BPA-PEG-LP encapsulating doxorubicin (BPA-PEG-LPDOX, 2 mg/kg/day as the DOX dosage) or PEG-modified liposomes encapsulating DOX (PEG-LPDOX). As a result, BPA-PEG-LPDOX significantly suppressed the growth of the DU145 cancer cells, whereas PEG-LPDOX at the same dosage as DOX showed little anti-cancer effect. The present study suggested that BPA-PEG-LP could be a useful drug carrier for the treatment of human prostate cancers.


Asunto(s)
Antineoplásicos/administración & dosificación , Doxorrubicina/análogos & derivados , Lectinas de Plantas/administración & dosificación , Neoplasias de la Próstata/tratamiento farmacológico , Animales , Antineoplásicos/farmacocinética , Línea Celular Tumoral , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Humanos , Liposomas , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Lectinas de Plantas/farmacocinética , Polietilenglicoles/administración & dosificación , Polietilenglicoles/farmacocinética , Ensayos Antitumor por Modelo de Xenoinjerto
9.
J Mol Recognit ; 29(6): 248-52, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26638121

RESUMEN

Andira anthelmia (tribe Dalbergieae), a plant from Brazilian Amazon, possesses a seed lectin that was purified by affinity chromatography in sepharose-mannose. This novel Dalbergieae lectin, named AAL, agglutinated rabbit erythrocytes treated with trypsin. The hemagglutinating activity of AAL was maintained after incubation at a wide range of temperature (40 to 70 °C) and pH, was shown to be dependent on divalent cations, and was inhibited by d-mannose and d-sucrose. AAL showed an electrophoretic profile in sodium dodecyl sulfate-polyacrylamide gel electrophoresis similar to other lectins of the tribe Dalbergieae, presenting a double band of molecular weight with approximately 20 kDa and other minor bands of 17, 15, and 13 kDa, being the smaller fragment glycosylated. AAL injected by intravenous route in mice showed antinociceptive activity in two behavioral tests (writhing and formalin). In the writhing test induced by acetic acid, AAL showed inhibitory effect at 0.01 mg/kg (68%), 0.1 mg/kg (46%) and 1 mg/kg (74%). In the formalin test, AAL (0.1 mg/kg) inhibited by 48% the licking time in the inflammatory phase, an effect that was recovered by the lectin association with mannose. In conclusion, AAL presents analgesic effect involving the lectin domain via peripheral mechanisms of inflammatory nociception. This activity highlights the importance of lectins as tools to be used for understanding the interaction of protein-carbohydrate in processes associated to inflammatory pain. Copyright © 2015 John Wiley & Sons, Ltd.


Asunto(s)
Analgésicos/administración & dosificación , Analgésicos/aislamiento & purificación , Fabaceae/química , Dolor/tratamiento farmacológico , Lectinas de Plantas/administración & dosificación , Lectinas de Plantas/aislamiento & purificación , Analgésicos/química , Analgésicos/farmacología , Animales , Cromatografía de Afinidad , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Eritrocitos/efectos de los fármacos , Pruebas de Hemaglutinación , Concentración de Iones de Hidrógeno , Manosa/farmacología , Ratones , Peso Molecular , Dolor/etiología , Lectinas de Plantas/química , Lectinas de Plantas/farmacología , Estabilidad Proteica , Conejos , Sacarosa/farmacología , Temperatura
10.
Pharm Biol ; 54(4): 686-91, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26427318

RESUMEN

CONTEXT: Antibacterial resistance has dramatically increased and resulted in serious health problems worldwide. One appealing strategy to overcome this resistance problem is the use of combinations of antibacterial compounds to increase their potency. OBJECTIVE: The objective of this study is to determine the synergistic effects of artocarpin for ampicillin, norfloxacin, and tetracycline against methicillin-resistant Staphylococcus aureus (MRSA) as well as the Gram-negative bacteria Pseudomonas aeruginosa and Escherichia coli. MATERIALS AND METHODS: A broth microdilution method (1.95-250 µg/mL) was used to determine the minimum inhibitory concentration (MIC) of artocarpin and the antibiotics. Any synergistic effects were evaluated at their own MIC using the checkerboard method and a time-kill assay at 37 °C for 24 h. RESULTS AND DISCUSSION: Artocarpin showed antibacterial activity against MRSA and E. coli with an MIC value of 62.5 µg/mL, and against P. aeruginosa with an MIC value of 250 µg/mL. The interaction of artocarpin with all tested antibiotics produced synergistic effects against MRSA with a fractional inhibitory concentration index (FICI) of 0.15-0.37. In addition, a combination of artocarpin and norfloxacin showed a synergistic effect against E. coli with an FICI value of 0.37, while the combinations of artocarpin and tetracycline as well as artocarpin and norfloxacin exhibited synergy interactions against P. aeruginosa with FICI values of 0.24 and 0.37, respectively. Time-kill assays indicated that artocarpin enhanced the antimicrobial activities of tetracycline, ampicillin, and norfloxacin against MRSA as well as Gram-negative bacteria.


Asunto(s)
Antibacterianos/administración & dosificación , Escherichia coli/efectos de los fármacos , Lectinas de Unión a Manosa/administración & dosificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Lectinas de Plantas/administración & dosificación , Pseudomonas aeruginosa/efectos de los fármacos , Antibacterianos/aislamiento & purificación , Artocarpus , Combinación de Medicamentos , Sinergismo Farmacológico , Escherichia coli/fisiología , Humanos , Lectinas de Unión a Manosa/aislamiento & purificación , Meticilina/administración & dosificación , Staphylococcus aureus Resistente a Meticilina/fisiología , Pruebas de Sensibilidad Microbiana/métodos , Extractos Vegetales/administración & dosificación , Extractos Vegetales/aislamiento & purificación , Lectinas de Plantas/aislamiento & purificación , Pseudomonas aeruginosa/fisiología
11.
Mol Cell Biochem ; 408(1-2): 73-87, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26152904

RESUMEN

In this study, we evaluated the effects of Korean mistletoe (Viscum album L. var. coloratum) coated with a biodegradable polymer (Eudragit(®)) wall on the growth of mouse melanoma in vivo. Oral administration of 4% (430 mg/kg/day) enteric-coated mistletoe resulted in a significant reduction in tumor volume on day 14 compared to the negative control group in B16F10 melanoma-inoculated BDF1 mice. When we measured the survival rate, enteric-coated mistletoe-received mice had a higher survival rate after day 12. Also, we investigated the mechanism involving the cancer cell growth inhibition when melanoma cells were treated with Korean mistletoe lectin (Viscum album L. var. coloratum agglutinin, VCA) and its extract in vitro. As a result, a significant G0/G1 arrest was observed in both B16BL6 and B16F10 melanoma cells with VCA or mistletoe extract. In addition, VCA or mistletoe extract induced an increase in both early and late apoptosis in cells. When we studied the molecular mechanism, our results showed that VCA and mistletoe extract can increase activated multiple caspases (caspase-1, 3, 4, 5, 6, 7, 8, and 9), dose-dependently. We also found out that VCA and mistletoe treatment causes a significant decrease in the expression of procaspase-3 and 8.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Melanoma Experimental/tratamiento farmacológico , Muérdago/metabolismo , Lectinas de Plantas/administración & dosificación , Proteínas Inactivadoras de Ribosomas/administración & dosificación , Neoplasias Cutáneas/tratamiento farmacológico , Administración Oral , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Apoptosis , Caspasa 3/metabolismo , Caspasa 8/metabolismo , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Técnicas In Vitro , Melanoma Experimental/metabolismo , Ratones , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Lectinas de Plantas/química , Lectinas de Plantas/farmacología , Polímeros/química , Proteínas Inactivadoras de Ribosomas/química , Proteínas Inactivadoras de Ribosomas/farmacología , Neoplasias Cutáneas/metabolismo , Análisis de Supervivencia
12.
J Virol ; 87(11): 6257-69, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23536670

RESUMEN

Griffithsin, which binds N-linked glycans on gp120 to prevent HIV entry, has the most potent HIV-1 inhibitory activity described for any antiviral lectin and is being developed for topical preexposure prophylaxis. The current studies were designed to further assess its potential by exploring its activity against herpes simplex virus 2 (HSV-2), a cofactor for HIV acquisition, in vitro and in a murine model. Safety was evaluated by examining its impact on epithelial barrier integrity in polarized cultures and testing whether repeated intravaginal dosing potentiates the susceptibility of mice to genital herpes. Griffithsin displayed modest inhibitory activity against HSV-2 if present during viral entry but completely blocked plaque formation if present postentry, reduced plaque size, and prevented cell-to-cell spread. These in vitro findings translated to significant protection against genital herpes in mice treated with 0.1% griffithsin gel. Griffithsin, but not placebo gel, prevented viral spread (visualized with a luciferase-expressing virus), significantly reduced disease scores, and resulted in greater survival (P < 0.05, log rank test). Protection persisted when HSV-2 was introduced in seminal plasma. Although griffithsin triggered a small decline in transepithelial electrical resistance in polarized cultures, this did not translate to any significant increase in the ability of HIV to migrate from the apical to the basolateral chamber nor to an increase in susceptibility to HSV-2 in mice treated with griffithsin gel for 7 days. These findings demonstrate that griffithsin inhibits HSV-2 by a unique mechanism of blocking cell-to-cell spread and support its further development for HIV and HSV-2 prevention.


Asunto(s)
Antivirales/administración & dosificación , Herpes Genital/prevención & control , Herpes Genital/virología , Herpesvirus Humano 2/efectos de los fármacos , Lectinas de Plantas/administración & dosificación , Animales , Femenino , Herpesvirus Humano 2/fisiología , Humanos , Ratones , Ratones Endogámicos BALB C , Internalización del Virus/efectos de los fármacos
13.
Biomacromolecules ; 15(6): 2012-8, 2014 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-24761752

RESUMEN

In this study, we fabricated lectin-tagged fluorescent polymeric nanoparticles approximately 35 nm in diameter using biocompatible polymers conjugated with lectins for the purpose of detecting sialic acid on a living cell surface, which is one of the most important biomarkers for cancer diagnosis. Through cellular experiments, we successfully detected sialic acid overexpression on cancerous cells with high specificity. These fluorescent polymeric nanoparticles can be useful as a potential bioimaging probe for detecting diseased cells.


Asunto(s)
Membrana Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Colorantes Fluorescentes/administración & dosificación , Ácido N-Acetilneuramínico , Nanopartículas/administración & dosificación , Lectinas de Plantas/administración & dosificación , Polímeros/administración & dosificación , Animales , Membrana Celular/metabolismo , Colorantes Fluorescentes/metabolismo , Células HeLa , Humanos , Células MCF-7 , Ratones , Ácido N-Acetilneuramínico/metabolismo , Nanopartículas/metabolismo , Corteza de la Planta , Extractos Vegetales/administración & dosificación , Extractos Vegetales/metabolismo , Lectinas de Plantas/metabolismo , Polímeros/metabolismo , Sambucus nigra
14.
Cancer Immunol Immunother ; 62(8): 1283-92, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23832140

RESUMEN

Mistletoe extract (ME) is applied as an adjuvant treatment in cancer therapy in thousands of patients each year in Europe. The main immunostimulating component of mistletoe extract, mistletoe lectin, recently has been shown to be a pattern recognition receptor ligand and hence is binding to an important class of pathogen-sensing receptors. Pattern recognition receptor ligands are potent activators of dendritic cells. This activation is a prerequisite for a full-blown T-cell response against cancer cells. Pattern recognition receptor ligands are increasingly recognized as important players in cancer immunotherapy. We collect evidence from case studies on spontaneous regression, from epidemiology, from experiments in a mouse cancer model, and from protein structure comparisons to argue that a combination of mistletoe therapy with other pattern recognition receptor ligand substances leads to an increased immune stimulatory effect. We show that mistletoe lectin is a plant protein of bacterial origin with a 3D structure very similar to shiga toxin from Shigella dysenteriae, which explains the remarkable immunogenicity of mistletoe lectin. Secondly, we show that a combination of pattern recognition receptor ligands applied metronomically in a cancer mouse model leads to complete remission, while single pattern recognition receptor ligands slowed tumor growth. Taken together, we propose to combine mistletoe drugs with other pattern recognition receptor ligand drugs to increase its efficacy in adjuvant or even primary cancer therapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Muérdago/metabolismo , Neoplasias Pancreáticas/tratamiento farmacológico , Lectinas de Plantas/química , Receptores Toll-Like/agonistas , Animales , Línea Celular Tumoral , Flagelina/administración & dosificación , Humanos , Imidazoles/administración & dosificación , Lipopolisacáridos/administración & dosificación , Ratones , Ratones Endogámicos C57BL , Modelos Moleculares , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Fitoterapia , Lectinas de Plantas/administración & dosificación , Conformación Proteica , Toxina Shiga/química , Factores de Tiempo , Resultado del Tratamiento , Carga Tumoral/efectos de los fármacos
15.
J Immunol ; 186(7): 4253-62, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21357262

RESUMEN

In this study, we demonstrated a new airway Ag sampling site by analyzing tissue sections of the murine nasal passages. We revealed the presence of respiratory M cells, which had the ability to take up OVA and recombinant Salmonella typhimurium expressing GFP, in the turbinates covered with single-layer epithelium. These M cells were also capable of taking up respiratory pathogen group A Streptococcus after nasal challenge. Inhibitor of DNA binding/differentiation 2 (Id2)-deficient mice, which are deficient in lymphoid tissues, including nasopharynx-associated lymphoid tissue, had a similar frequency of M cell clusters in their nasal epithelia to that of their littermates, Id2(+/-) mice. The titers of Ag-specific Abs were as high in Id2(-/-) mice as in Id2(+/-) mice after nasal immunization with recombinant Salmonella-ToxC or group A Streptococcus, indicating that respiratory M cells were capable of sampling inhaled bacterial Ag to initiate an Ag-specific immune response. Taken together, these findings suggest that respiratory M cells act as a nasopharynx-associated lymphoid tissue-independent alternative gateway for Ag sampling and subsequent induction of Ag-specific immune responses in the upper respiratory tract.


Asunto(s)
Antígenos Bacterianos/administración & dosificación , Tejido Linfoide/inmunología , Mucosa Nasal/inmunología , Nasofaringe/inmunología , Lectinas de Plantas/administración & dosificación , Cornetes Nasales/inmunología , Administración por Inhalación , Animales , Antígenos Bacterianos/inmunología , Células Epiteliales/inmunología , Células Epiteliales/microbiología , Células Epiteliales/ultraestructura , Recuento de Linfocitos , Tejido Linfoide/microbiología , Tejido Linfoide/ultraestructura , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos BALB C , Ratones Noqueados , Cavidad Nasal/inmunología , Cavidad Nasal/microbiología , Cavidad Nasal/ultraestructura , Mucosa Nasal/microbiología , Mucosa Nasal/ultraestructura , Nasofaringe/microbiología , Nasofaringe/ultraestructura , Lectinas de Plantas/biosíntesis , Lectinas de Plantas/inmunología , Salmonella typhimurium/inmunología , Streptococcus pyogenes/inmunología , Cornetes Nasales/microbiología , Cornetes Nasales/ultraestructura , Ulex/inmunología , Aglutininas del Germen de Trigo/inmunología
16.
Int J Mol Sci ; 14(11): 21689-704, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24189218

RESUMEN

In this study, we sought to investigate the role of soybean agglutinin (SBA) in mediating membrane permeability and the mechanical barrier function of intestinal epithelial cells. The IPEC-J2 cells were cultured and treated with 0, 0.5, 1.0, 1.5, 2.0, 2.5, or 3.0 mg/mL SBA. Transepithelial electrical resistance (TEER) and alkaline phosphatase (AP) activity were measured to evaluate membrane permeability. The results showed a significant decrease in TEER values (p < 0.05) in a time- and dose-dependent manner, and a pronounced increase in AP activity (p < 0.05). Cell growth and cell morphology were used to evaluate the cell viability. A significant cell growth inhibition (p < 0.05) and alteration of morphology were observed when the concentration of SBA was increased. The results of western blotting showed that the expression levels of occludin and claudin-3 were decreased by 31% and 64% compared to those of the control, respectively (p < 0.05). In addition, immunofluorescence labeling indicated an obvious decrease in staining of these targets and changes in their localizations. In conclusion, SBA increased the membrane permeability, inhibited the cell viability and reduced the levels of tight junction proteins (occludin and claudin-3), leading to a decrease in mechanical barrier function in intestinal epithelial cells.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Mucosa Intestinal/metabolismo , Lectinas de Plantas/administración & dosificación , Proteínas de Soja/administración & dosificación , Proteínas de Uniones Estrechas/biosíntesis , Animales , Permeabilidad de la Membrana Celular/efectos de los fármacos , Mucosa Intestinal/citología , Mucosa Intestinal/efectos de los fármacos , Porcinos , Proteínas de Uniones Estrechas/metabolismo , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/metabolismo
17.
Dev Biol ; 349(2): 342-9, 2011 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-21050843

RESUMEN

The mammalian embryo represents a fundamental paradox in biology. Its location within the uterus, especially early during development when embryonic cardiovascular development and placental blood flow are not well-established, leads to an obligate hypoxic environment. Despite this hypoxia, the embryonic cells are able to undergo remarkable growth, morphogenesis, and differentiation. Recent evidence suggests that embryonic organ differentiation, including pancreatic ß-cells, is tightly regulated by oxygen levels. Since a major determinant of oxygen tension in mammalian embryos after implantation is embryonic blood flow, here we used a novel survivable in utero intracardiac injection technique to deliver a vascular tracer to living mouse embryos. Once injected, the embryonic heart could be visualized to continue contracting normally, thereby distributing the tracer specifically only to those regions where embryonic blood was flowing. We found that the embryonic pancreas early in development shows a remarkable paucity of blood flow and that the presence of blood flow correlates with the differentiation state of the developing pancreatic epithelial cells in the region of the blood flow.


Asunto(s)
Diferenciación Celular/fisiología , Embrión de Mamíferos/irrigación sanguínea , Oxígeno/metabolismo , Páncreas/embriología , Ultrasonografía Intervencional/métodos , Animales , Técnicas de Imagen Cardíaca/métodos , Fluoresceínas/administración & dosificación , Inmunohistoquímica , Ratones , Microscopía Fluorescente , Páncreas/irrigación sanguínea , Páncreas/citología , Páncreas/metabolismo , Lectinas de Plantas/administración & dosificación
18.
Ann Allergy Asthma Immunol ; 108(5): 367-72, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22541410

RESUMEN

BACKGROUND: As the frequency of natural rubber latex (NRL) allergy has increased, attempts have been made to diminish exposure in high-risk patients. Despite some good results, complete NRL avoidance was not possible, so latex immunotherapy was developed. OBJECTIVE: To examine variations in immunologic parameters, clinical efficacy, and safety of NRL sublingual immunotherapy (SLIT). METHODS: This prospective, observational, open, case-control study included 23 patients (18 patients receiving NRL SLIT and 5 controls). Skin prick, conjunctival provocation, and in-use tests with NRL, specific IgE and specific IgG4 to NRL, specific IgE to recombinant NRL allergens, and basophil activation test (BAT) with whole latex, natural, and recombinant allergens were performed before immunotherapy (T0) and at 6 (T1) and 12 months (T2) of treatment. RESULTS: Patients were sensitized to Hev b 5, Hev b 6.01, and Hev b 6.02 proteins, optimal for SLIT. Changes in specific IgE were not significant. Increases in specific IgG4 between T1 and T2 were larger in the active group. BAT determinations showed significant decreases in recombinant Hev b 6.01 and natural Hev b 6.02 in the active group at T1 but not at T2. Both groups had new sensitizations at T1 but not at T2. The active group had significant increases in the response threshold in the in vivo tests at T1 and T2. Adverse effects were limited to local reactions. CONCLUSION: NRL SLIT is effective and safe in children with latex allergy. Our results suggest that specific IgE determinations and BAT measurements to natural and recombinant latex allergens may allow obtaining an allergen-based diagnosis to help determine specific immunotherapy.


Asunto(s)
Alérgenos/administración & dosificación , Antígenos de Plantas/administración & dosificación , Péptidos Catiónicos Antimicrobianos/inmunología , Desensibilización Inmunológica/métodos , Hipersensibilidad al Látex/terapia , Lectinas de Plantas/inmunología , Proteínas de Plantas/administración & dosificación , Administración Sublingual , Adolescente , Alérgenos/efectos adversos , Alérgenos/inmunología , Antígenos de Plantas/efectos adversos , Antígenos de Plantas/inmunología , Péptidos Catiónicos Antimicrobianos/administración & dosificación , Péptidos Catiónicos Antimicrobianos/efectos adversos , Basófilos/inmunología , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Tolerancia Inmunológica/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Hipersensibilidad al Látex/inmunología , Masculino , Lectinas de Plantas/administración & dosificación , Lectinas de Plantas/efectos adversos , Proteínas de Plantas/efectos adversos , Proteínas de Plantas/inmunología , Estudios Prospectivos , Goma/administración & dosificación , Goma/química , Pruebas Cutáneas , Resultado del Tratamiento
19.
Neurol Sci ; 33(6): 1365-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22437495

RESUMEN

Migraine is common in children, but few specific drugs are available. We performed an open-label comparison of effects of two nutraceutical preparations (ginkgolide B vs. Griffonia simplicifolia extract) on outcomes in 374 school-age children (mean 10.7 years) with migraine without aura. Half of them received ginkgolide B; and half, Griffonia simplicifolia. Both preparations were given orally twice a day for 6 months. Patients kept a headache diary. Outcomes at the beginning and end of treatment were compared. Both preparations reduced all outcome measures after 6 months of treatment. However, reductions in headache frequency, duration and intensity, PedMIDAS score and behavioural reactions to headache were significantly greater in the ginkgolide B group. Both nutraceutical treatments appear promising in paediatric migraine without aura, particularly because of their lack of side effects. However, the ginkgolide B preparation was significantly more effective in the medium-term (6 months).


Asunto(s)
Conducta Infantil/psicología , Suplementos Dietéticos , Ginkgólidos/administración & dosificación , Lactonas/administración & dosificación , Trastornos Migrañosos/prevención & control , Trastornos Migrañosos/psicología , Lectinas de Plantas/administración & dosificación , Niño , Evaluación de la Discapacidad , Femenino , Griffonia , Humanos , Masculino , Trastornos Migrañosos/epidemiología , Proyectos Piloto , Resultado del Tratamiento
20.
PLoS One ; 17(1): e0261775, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35051209

RESUMEN

HIV pre-exposure prophylaxis (PrEP) is dominated by clinical therapeutic antiretroviral (ARV) drugs. Griffithsin (GRFT) is a non-ARV lectin with potent anti-HIV activity. GRFT's preclinical safety, lack of systemic absorption after vaginal administration in animal studies, and lack of cross-resistance with existing ARV drugs prompted its development for topical HIV PrEP. We investigated safety, pharmacokinetics (PK), pharmacodynamics (PD), and immunogenicity of PC-6500 (0.1% GRFT in a carrageenan (CG) gel) in healthy women after vaginal administration. This randomized, placebo-controlled, parallel group, double-blind first-in-human phase 1 study enrolled healthy, HIV-negative, non-pregnant women aged 24-45 years. In the open label period, all participants (n = 7) received single dose of PC-6500. In the randomized period, participants (n = 13) were instructed to self-administer 14 doses of PC-6500 or its matching CG placebo (PC-535) once daily for 14 days. The primary outcomes were safety and PK after single dose, and then after 14 days of dosing. Exploratory outcomes were GRFT concentrations in cervicovaginal fluids, PD, inflammatory mediators and gene expression in ectocervical biopsies. This trial is registered with ClinicalTrials.gov, number NCT02875119. No significant adverse events were recorded in clinical or laboratory results or histopathological evaluations in cervicovaginal mucosa, and no anti-drug (GRFT) antibodies were detected in serum. No cervicovaginal proinflammatory responses and no changes in the ectocervical transcriptome were evident. Decreased levels of proinflammatory chemokines (CXCL8, CCL5 and CCL20) were observed. GRFT was not detected in plasma. GRFT and GRFT/CG in cervicovaginal lavage samples inhibited HIV and HPV, respectively, in vitro in a dose-dependent fashion. These data suggest GRFT formulated in a CG gel is a safe and promising on-demand multipurpose prevention technology product that warrants further investigation.


Asunto(s)
Carragenina/administración & dosificación , Infecciones por VIH/prevención & control , Infecciones por Papillomavirus/prevención & control , Lectinas de Plantas/administración & dosificación , Profilaxis Pre-Exposición , Cremas, Espumas y Geles Vaginales/administración & dosificación , Administración Intravaginal , Adolescente , Adulto , Método Doble Ciego , Femenino , VIH-1 , Humanos , Persona de Mediana Edad , Papillomaviridae
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