RESUMEN
Exposure to pesticides across species has been associated with cognitive and motor impairments. As the problem impacts ecosystem stability, food production and public health, it is urgent to develop multifactorial solutions, from regulatory legislation to pharmacological alternatives that ameliorate the impairments. Fipronil, a commonly used insecticide, acts as a GABAA receptor (GABAAR) antagonist and induces motor impairments in vertebrates and invertebrates. Here, we hypothesized that kaempferol, a secondary metabolite derived from plants, acting as an allosteric modulator of GABAARs, would protect against the negative effects induced by the administration of fipronil in adults of the fruit fly Drosophila melanogaster. We further evaluated our hypothesis via co-administration of flumazenil, a competitive antagonist on the GABAAR, and through in silico analyses. We administered kaempferol prophylactically at three concentrations (10, 30 and 50â µmolâ l-1) and evaluated its protective effects against motor impairments induced by fipronil. We then used a single dose of kaempferol (50â µmolâ l-1) to evaluate its protective effect while administering flumazenil. We found that oral administration of fipronil impaired motor control and walking ability. In contrast, kaempferol was innocuous and protected flies from developing the motor-impaired phenotype, whereas the co-administration of flumazenil counteracted these protective effects. These results are supported by the binding of the ligands with the receptor. Together, our results suggest that kaempferol exerts a protective effect against fipronil via positive allosteric modulation of GABAARs, probably within brain areas such as the central complex and the mushroom bodies. These findings further support current attempts to use metabolites derived from plants as protectors against impairments produced by pesticides.
Asunto(s)
Insecticidas , Trastornos Motores , Plaguicidas , Animales , Insecticidas/toxicidad , Drosophila melanogaster/metabolismo , Receptores de GABA-A/metabolismo , Flumazenil , Quempferoles/farmacología , Flavonoides , Ligandos , Ecosistema , Drosophila/metabolismo , Antagonistas de Receptores de GABA-ARESUMEN
Bacterial spot is one of the most serious diseases of tomato. It is caused by four species of Xanthomonas: X. euvesicatoria, X. gardneri, X. perforans, and X. vesicatoria. Contaminated or infected seed can be a major source of inoculum for this disease. The use of certified pathogen-free seed is one of the primary management practices to reduce the inoculum load in commercial production. Current seed testing protocols rely mainly on plating the seed extract and conventional PCR; however, the plating method cannot detect viable but nonculturable cells, and the conventional PCR assay has limited capability to differentiate DNA extracted from viable or dead bacterial cells. To improve the sensitivity and specificity of the tomato seed testing method for bacterial spot pathogens, a long-amplicon quantitative PCR (qPCR) assay coupled with propidium monoazide (PMA-qPCR) was developed to quantify selectively the four pathogenic Xanthomonas species in tomato seed. The optimized PMA-qPCR procedure was evaluated on pure bacterial suspensions, bacteria-spiked seed extracts, and seed extracts of inoculated and naturally infected seed. A crude DNA extraction protocol also was developed, and PMA-qPCR with crude bacterial DNA extracts resulted in accurate quantification of 104 to 108 CFU/ml of viable bacteria when mixed with dead cells at concentrations as high as 107 CFU/ml in the seed extracts. With DNA purified from concentrated seed extracts, the PMA-qPCR assay was able to detect DNA of the target pathogens in seed samples spiked with ≥75 CFU/ml (about 0.5 CFU/seed) of the viable pathogens. Latent class analysis of the inoculated and naturally infected seed samples showed that the PMA-qPCR assay had greater sensitivity than plating the seed extracts on the semiselective modified Tween Medium B and CKTM media for all four target species. Being much faster and more sensitive than dilution plating, the PMA-qPCR assay has potential to be used as a standalone tool or in combination with the plating method to improve tomato seed testing and advance the production of clean seed.
Asunto(s)
Solanum lycopersicum , Xanthomonas , Solanum lycopersicum/microbiología , Extractos Vegetales , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Semillas , Xanthomonas/genéticaRESUMEN
Aureocin A53 is an N-formylated antimicrobial peptide (AMP) produced by Staphylococcus aureus. Aureocin A53 has a broad spectrum of antimicrobial activity against human and animal pathogens. In the present study, its antagonistic activity was investigated towards 30 strains of S. aureus and 30 strains of Streptococcus spp. isolated from bovine mastitis cases in Brazil. Bovine mastitis is a disease that causes a major economic impact worldwide. Aureocin A53 inhibited the growth of all 60 strains tested, including multidrug-resistant streptococcal isolates and strains of S. aureus belonging to different pulsotypes. This AMP proved to be bactericidal against the six target strains randomly selected among staphylococci and streptococci, also exhibiting a lytic mode of action against the staphylococcal cells. Furthermore, it was determined that 2,048 AU/mL of the AMP were required to inhibit 99.99% of the cell growth of the strain less sensitive to aureocin A53. Aureocin A53 was not toxic to bovine mammary gland epithelial cells after a 24-h exposure and maintained its antimicrobial activity when tested in the excised-teat model against strains of S. aureus and Streptococcus agalactiae, the species responsible for most intramammary infections, not only in Brazil but in other countries as well. Therefore, the use of aureocin A53 in the development of new pharmacological products for the prophylaxis and/or treatment of bovine mastitis was considered promising.
Asunto(s)
Antiinfecciosos , Mastitis Bovina , Infecciones Estafilocócicas , Femenino , Humanos , Bovinos , Animales , Staphylococcus aureus , Streptococcus agalactiae , Péptidos Antimicrobianos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/veterinaria , Staphylococcus , Antibacterianos/farmacología , Streptococcus , Antiinfecciosos/farmacología , Adenosina Monofosfato/farmacologíaRESUMEN
Due to the emergence of multidrug-resistant pathogens, it is necessary to develop options to fight infections caused by these agents. Lactoferrin (Lf) is a cationic nonheme multifunctional glycoprotein of the innate immune system of mammals that provides numerous benefits. Lf is bacteriostatic and/or bactericidal, can stimulate cell proliferation and differentiation, facilitate iron absorption, improve neural development and cognition, promote bone growth, prevent cancer and exert anti-inflammatory and immunoregulatory effects. Lactoferrin is present in colostrum and milk and is also produced by the secondary granules of polymorphonuclear leukocytes, which store this glycoprotein and release it at sites of infection. Lf is also present in many fluids and exocrine secretions, on the surfaces of the digestive, respiratory and reproductive systems that are commonly exposed to pathogens. Apo-Lf (an iron-free molecule) can be microbiostatic due to its ability to capture ferric iron, blocking the availability of host iron to pathogens. However, apo-Lf is mostly microbicidal via its interaction with the microbial surface, causing membrane damage and altering its permeability function. Lf can inhibit viral entry by binding to cell receptors or viral particles. Lf is also able to counter different important mechanisms evolved by microbial pathogens to infect and invade the host, such as adherence, colonization, invasion, production of biofilms and production of virulence factors such as proteases and toxins. Lf can also cause mitochondrial and caspase-dependent regulated cell death and apoptosis-like in pathogenic yeasts. All of these mechanisms are important targets for treatment with Lf. Holo-Lf (the iron-saturated molecule) can contain up to two ferric ions and can also be microbicidal against some pathogens. On the other hand, lactoferricins (Lfcins) are peptides derived from the N-terminus of Lf that are produced by proteolysis with pepsin under acidic conditions, and they cause similar effects on pathogens to those caused by the parental Lf. Synthetic analog peptides comprising the N-terminus Lf region similarly exhibit potent antimicrobial properties. Importantly, there are no reported pathogens that are resistant to Lf and Lfcins; in addition, Lf and Lfcins have shown a synergistic effect with antimicrobial and antiviral drugs. Due to the Lf properties being microbiostatic, microbicidal, anti-inflammatory and an immune modulator, it represents an excellent natural alternative either alone or as adjuvant in the combat to antibiotic multidrug-resistant bacteria and other pathogens. This review aimed to evaluate the data that appeared in the literature about the effects of Lf and its derived peptides on pathogenic bacteria, protozoa, fungi and viruses and how Lf and Lfcins inhibit the mechanisms developed by these pathogens to cause disease.
Asunto(s)
Antiinfecciosos/química , Antiinfecciosos/farmacología , Lactoferrina/química , Lactoferrina/farmacología , Péptidos/química , Péptidos/farmacología , Animales , Antiinfecciosos/síntesis química , Antiparasitarios/síntesis química , Antiparasitarios/química , Antiparasitarios/farmacología , Bacterias/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Pared Celular/efectos de los fármacos , Técnicas de Química Sintética , Hongos/efectos de los fármacos , Interacciones Huésped-Patógeno , Humanos , Péptidos/síntesis química , Proteolisis/efectos de los fármacos , Relación Estructura-Actividad , Virulencia/efectos de los fármacos , Factores de Virulencia , Virus/efectos de los fármacosRESUMEN
Strategies for the control of sulfate-reducing bacteria (SRB) in the oil industry involve the use of high concentrations of biocides, but these may induce bacterial resistance and/or be harmful to public health and the environment. Essential oils (EO) produced by plants inhibit the growth of different microorganisms and are a possible alternative for controlling SRB. We aimed to characterize the bacterial community of produced water obtained from a Brazilian petroleum facility using molecular methods, as well as to evaluate the antimicrobial activity of EO from different plants and their major components against Desulfovibrio alaskensis NCIMB 13491 and against SRB growth directly in the produced water. Denaturing gradient gel electrophoresis revealed the presence of the genera Pelobacter and Marinobacterium, Geotoga petraea, and the SRB Desulfoplanes formicivorans in our produced water samples. Sequencing of dsrA insert-containing clones confirmed the presence of sequences related to D. formicivorans. EO obtained from Citrus aurantifolia, Lippia alba LA44 and Cymbopogon citratus, as well as citral, linalool, eugenol and geraniol, greatly inhibited (minimum inhibitory concentration (MIC) = 78 µg/mL) the growth of D. alaskensis in a liquid medium. The same MIC was obtained directly in the produced water with EO from L. alba LA44 (containing 82% citral) and with pure citral. These findings may help to control detrimental bacteria in the oil industry.
Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Industria del Petróleo y Gas , Aceites Volátiles/farmacología , Sulfatos/metabolismo , Agua , Bacterias/genética , Pruebas de Sensibilidad MicrobianaRESUMEN
Production of phytohormones is one of the main mechanisms to explain the beneficial effects of plant growth-promoting rhizobacteria (PGPR) such as Azospirillum sp. The PGPRs induce plant growth and development, and reduce stress susceptibility. However, little is known regarding the stress-related phytohormone abscisic acid (ABA) produced by bacteria. We investigated the effects of Azospirillum brasilense Sp 245 strain on Arabidopsis thaliana Col-0 and aba2-1 mutant plants, evaluating the morphophysiological and biochemical responses when watered and in drought. We used an in vitro-grown system to study changes in the root volume and architecture after inoculation with Azospirillum in Arabidopsis wild-type Col-0 and on the mutant aba2-1, during early growth. To examine Arabidopsis development and reproductive success as affected by the bacteria, ABA and drought, a pot experiment using Arabidopsis Col-0 plants was also carried out. Azospirillum brasilense augmented plant biomass, altered root architecture by increasing lateral roots number, stimulated photosynthetic and photoprotective pigments and retarded water loss in correlation with incremented ABA levels. As well, inoculation improved plants seed yield, plants survival, proline levels and relative leaf water content; it also decreased stomatal conductance, malondialdehyde and relative soil water content in plants submitted to drought. Arabidopsis inoculation with A. brasilense improved plants performance, especially in drought.
Asunto(s)
Ácido Abscísico/metabolismo , Arabidopsis/microbiología , Azospirillum brasilense/fisiología , Regulación de la Expresión Génica de las Plantas , Reguladores del Crecimiento de las Plantas/metabolismo , Ácido Abscísico/análisis , Arabidopsis/genética , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Biomasa , Clorofila/metabolismo , Sequías , Flores/genética , Flores/microbiología , Flores/fisiología , Peroxidación de Lípido , Fotosíntesis/fisiología , Reguladores del Crecimiento de las Plantas/análisis , Hojas de la Planta/genética , Hojas de la Planta/microbiología , Hojas de la Planta/fisiología , Raíces de Plantas/genética , Raíces de Plantas/microbiología , Raíces de Plantas/fisiología , Transpiración de Plantas/fisiología , Prolina/metabolismo , Plantones/genética , Plantones/microbiología , Plantones/fisiología , Semillas/genética , Semillas/microbiología , Semillas/fisiología , Agua/fisiologíaRESUMEN
Eleven bacterial strains were isolated at different soil depths from roots and rhizosphere of grapevines from a commercial vineyard. By 16S rRNA gene sequencing 10 different genera and 8 possible at species level were identified. From them, Bacillus licheniformis Rt4M10 and Pseudomonas fluorescens Rt6M10 were selected according to their characteristics as plant growth promoting rhizobacteria (PGPR). Both produced abscisic acid (ABA), indole-3-acetic acid (IAA) and the gibberellins A1 and A3 in chemically-defined medium. They also colonized roots of in vitro grown Vitis vinifera cv. Malbec plants. As result of bacterization ABA levels in 45 days-old in vitro plants were increased 76-fold by B. licheniformis and 40-fold by P. fluorescens as compared to controls. Both bacteria diminished plant water loss rate in correlation with increments of ABA. Twenty and 30 days post bacterization the plants incremented terpenes. The monoterpenes α-pinene, terpinolene, 4-carene, limonene, eucalyptol and lilac aldehyde A, and the sesquiterpenes α-bergamotene, α-farnesene, nerolidol and farnesol were assessed by gas chromatography-electron impact mass spectrometry analysis. α-Pinene and nerolidol were the most abundant (µg per g of tissue in plants bacterized with P. fluorescens). Only α-pinene, eucalyptol and farnesol were identified at low concentration in non-bacterized plants treated with ABA, while no terpenes were detected in controls. The results obtained along with others from literature suggest that B. licheniformis and P. fluorescens act as stress alleviators by inducing ABA synthesis so diminishing water losses. These bacteria also elicit synthesis of compounds of plant defense via an ABA independent mechanism.
Asunto(s)
Ácido Abscísico/metabolismo , Bacterias/aislamiento & purificación , Raíces de Plantas/microbiología , Transpiración de Plantas , Rizosfera , Terpenos/metabolismo , Vitis/microbiología , Ácido Abscísico/farmacología , Bacterias/crecimiento & desarrollo , Recuento de Colonia Microbiana , Cromatografía de Gases y Espectrometría de Masas , Concentración de Iones de Hidrógeno , Ácidos Indolacéticos/metabolismo , Filogenia , Transpiración de Plantas/efectos de los fármacos , ARN Ribosómico 16S/genética , Terpenos/química , Técnicas de Cultivo de Tejidos , Vitis/inmunología , Vitis/fisiologíaRESUMEN
Fonsecaea pedrosoi is a melanized fungus that causes chromoblastomycosis (CBM), a tropical neglected disease responsible for chronic and disability-related subcutaneous mycosis. Given the challenging nature of CBM treatment, the study of new targets and novel bioactive drugs capable of improving patient life quality is urgent. In the present work, we detected a calcineurin activity in F. pedrosoi conidial form, employing primarily colorimetric, immunoblotting and flow cytometry assays. Our findings reveal that the calcineurin activity of F. pedrosoi was stimulated by Ca2+/calmodulin, inhibited by EGTA and specific inhibitors, such as tacrolimus (FK506) and cyclosporine A (CsA), and proved to be insensitive to okadaic acid. In addition, FK506 and CsA were able to affect the cellular viability and the fungal proliferation. This effect was corroborated by transmission electron microscopy that showed both calcineurin inhibitors promoted profound changes in the ultrastructure of conidia, causing mainly cytoplasm condensation and intense vacuolization that are clear indication of cell death. Our data indicated that FK506 exhibited the highest effectiveness, with a minimum inhibitory concentration (MIC) of 3.12 mg/L, whereas CsA required 15.6 mg/L to inhibit 100% of conidial growth. Interestingly, when both were combined with itraconazole, they demonstrated anti-F. pedrosoi activity, exhibiting a synergistic effect. Moreover, the fungal filamentation was affected after treatment with both calcineurin inhibitors. These data corroborate with other calcineurin studies in fungal cells and open up further discussions aiming to establish the role of this enzyme as a potential target for antifungal therapy against CBM infections.
RESUMEN
Xanthomonas arboricola pv. pruni (Xap) causes bacterial spot, a major worldwide disease of Prunus species. Very few chemical management options are available for this disease and frequent applications of oxytetracycline (OTC) in the United States peach orchards have raised concerns about resistance development. During 2017-2020, 430 Xap strains were collected from ten peach orchards in South Carolina. Seven OTC-resistant (OTC R ) Xap strains were found in 2017 and 2020 from four orchards about 20-270 km apart. Interestingly, the seven strains were also resistant to streptomycin (STR). Six strains grew on media amended with ≤100 µg/mL OTC, while one strain, R1, grew on ≤250 µg/mL OTC. Genome sequence analysis of four representative OTC R strains revealed a 14-20 kb plasmid carrying tetC, tetR, and strAB in each strain. These three genes were transferable to Xanthomonas perforans via conjugation, and they were PCR confirmed in all seven OTC R Xap strains. When tetC and tetR were cloned and expressed together in a sensitive strain, the transconjugants showed resistance to ≤100 µg/mL OTC. When tetC was cloned and expressed alone in a sensitive strain, the transconjugants showed resistance to ≤250 µg/mL OTC. TetC and tetR expression was inducible by OTC in all six wild-type strains resistant to ≤100 µg/mL OTC. However, in the R1 strain resistant to ≤250 µg/mL OTC, tetR was not expressed, possibly due to the presence of Tn3 in the tetR gene, and in this case tetC was constitutively expressed. These data suggest that tetC confers OTC resistance in Xap strains, and tetR regulates the level of OTC resistance conferred by tetC. To our knowledge, this is the first report of OTC resistance in plant pathogenic xanthomonads.
RESUMEN
Wilms tumor is a frequent malignant neoplasia in pediatric population. Extension to the inferior vena cava is a complication that occurs in approximately 4%-15% of cases. Surgical techniques derived from the field of adult transplant surgery allow the resection of the tumor with its thrombus extension. In the case of a 6-year-old male patient with a stage III Wilms tumor that originated from the left renal vein, thrombectomy and left radical nephroureterectomy were accomplished without extracorporeal circulation. Surgical technique applied in adult transplant surgery for removal of advanced renal tumors, could be a safe and feasible technique in pediatric population.
Asunto(s)
Carcinoma de Células Renales , Kava , Neoplasias Renales , Trombosis , Tumor de Wilms , Adulto , Carcinoma de Células Renales/cirugía , Puente Cardiopulmonar , Niño , Humanos , Neoplasias Renales/patología , Masculino , Nefrectomía/efectos adversos , Nefrectomía/métodos , Trombectomía , Trombosis/complicaciones , Trombosis/cirugía , Vena Cava Inferior/cirugía , Tumor de Wilms/complicaciones , Tumor de Wilms/patología , Tumor de Wilms/cirugíaRESUMEN
This study aimed to investigate controlled fermentation of cocoa beans with selected yeasts as starter cultures via integrating microbiological, biochemical, and chromatographic analyses. The steps involved in the yeast starter culture test were of the following order: 1) counting, isolation, purification, and biochemical identification of yeasts, 2) selection of ethanol-producing yeasts, 3) selection of thermotolerant yeasts, and 4) evaluation of physicochemical parameters of the selected yeasts in controlled fermentation of cocoa (F1 - Saccharomyces ssp. and Hanseniaspora ssp. and F2 - spontaneous fermentation - control). A total of 32 yeasts were isolated from three sampling points (M1, M2, and M3), which comprised 50% Candida ssp., 9.4% Rhodotorula ssp., 18.8% Saccharomyces ssp., and 18.8% Hanseniaspora ssp. The yeasts identified as Saccharomyces ssp. (n = 6) were subjected to the ethanol production test. Saccharomyces spp. CLV09 showed the highest concentration of ethanol in the simulated cocoa medium (3.5% v/v). Hanseniaspora spp. CVL20 and CVL19 strains showed the highest thermotolerance at 42°C after 72 h of growth. The starter cultures with Saccharomyces ssp. and Hanseniaspora ssp. showed a similar growth rate of the mesophilic aerobic population in both F1 and F2. Fermentation of the starter culture showed a higher production of organic acids than spontaneous fermentation (F2). Thus, Saccharomyces ssp. and Hanseniaspora ssp. can be used as a starter culture in cocoa fermentation.
RESUMEN
We investigated the interactions of abscisic acid (ABA) in the responses of grape leaf tissues to contrasting ultraviolet (UV)-B treatments. One-year-old field-grown plants of Vitis vinifera L. were exposed to photosynthetically active radiation (PAR) where solar UV-B was eliminated by using polyester filters, or where PAR was supplemented with UV-B irradiation. Treatments combinations included weekly foliar sprays of ABA or a water control. The levels of UV-B absorbing flavonols, quercetin and kaempferol were significantly decreased by filtering out UV-B, while applied ABA increased their content. Concentration of two hydroxycinnamic acids, caffeic and ferulic acids, were also increased by ABA, but not affected by plus UV-B (+UV-B) treatments. Levels of carotenoids and activities of the antioxidant enzymes, catalase, ascorbate peroxidase and peroxidase were elevated by +ABA treatments, but only if +UV-B was given. Cell membrane beta-sitosterol was enhanced by ABA independently of +UV-B. Changes in photoprotective compounds, antioxidant enzymatic activities and sterols were correlated with lessened membrane harm by UV-B, as assessed by ion leakage. Oxidative damage expressed as malondialdehyde content was increased under +UV-B treatments. Our results suggest that the defence system of grape leaf tissues against UV-B is activated by UV-B irradiation with ABA acting downstream in the signalling pathway.
Asunto(s)
Ácido Abscísico/metabolismo , Hojas de la Planta/metabolismo , Rayos Ultravioleta , Vitis/efectos de la radiación , Ácido Abscísico/farmacología , Antocianinas/metabolismo , Antioxidantes/metabolismo , Carotenoides/metabolismo , Catalasa/metabolismo , Clorofila/metabolismo , Quempferoles/metabolismo , Peroxidación de Lípido , Estrés Oxidativo , Peroxidasas/metabolismo , Hojas de la Planta/efectos de la radiación , Quercetina/metabolismo , Sitoesteroles/metabolismo , Vitis/metabolismoRESUMEN
Low-dose computed tomography (LDCT), an accepted U.S. screening tool for early lung cancer detection, is not widely-used in Puerto Rico. We investigated knowledge and attitudes about LDCT in focus groups of primary care physicians (PCP) and individuals at high risk for lung cancer (HRI) in Puerto Rico. Transcribed/translated audio-recorded discussions were analyzed with the constant comparison method. Both groups had limited knowledge about LDCT and concerns regarding insurance coverage. Most HRIs had never had a provider recommend LDCT and believed that having symptoms was necessary to obtain LDCT screening. Perceived barriers included fears about results and the procedure; a perceived benefit was having early detection and possibly being cured. Few PCPs had ever recommended LDCT to a patient, with those who had basing their decision on symptoms/smoking history but having challenges with insurance. More education on LDCT is needed among HRIs, and U.S. Preventive Services Task Force guidelines should be widely distributed to encourage physician recommendations.
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Neoplasias Pulmonares , Médicos de Atención Primaria , Detección Precoz del Cáncer , Conocimientos, Actitudes y Práctica en Salud , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Tamizaje Masivo , Percepción , Puerto RicoRESUMEN
The ß-amyloid peptide (1-42) is a molecule capable of aggregating into neurotoxic structures that have been implicated as potential etiological factors of Alzheimer's Disease. The aim of this study was to evaluate the inhibition of ß-amyloid aggregation of ethyl acetate and ethanolic extracts obtained from Ugni molinae leaves on neurotoxic actions of ß-amyloid aggregates. Chemical analyses were carried out with the extracts in order to determine their phenolic profile and its quantification. Both extracts showed a tendency to reduce neuronal deaths caused by ß-amyloid. This tendency was inversely proportional to the evaluated concentrations. Moreover, the effect of EAE and ETE on ß-amyloid aggregation was studied by fluorimetric T Thioflavin assay and transmission electronic microscopy (TEM); the extracts showed a modulation in the aggregation process. Partly, it is believed that these effects can be attributed to the polyphenolic compounds present in the extracts.
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Enfermedad de Alzheimer , Myrtaceae , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Humanos , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Fenoles/química , Extractos Vegetales/farmacología , Hojas de la Planta/químicaRESUMEN
Aristolochia trilobata, popularly known as "mil-homens," is widely used for treatment of stomach aches, colic, asthma, pulmonary diseases, diabetes, and skin affection. We evaluated the antinociceptive and anti-inflammatory activities of the essential oil (EO) and the main constituent, 6-methyl-5-hepten-2-yl acetate (sulcatyl acetate, SA). EO and SA (1, 10, and 100 mg/kg, p.o.) were evaluated using chemical (formalin-induced licking) and thermal (hot-plate) models of nociception or inflammation (carrageenan-induced cell migration into the subcutaneous air pouch, SAP). The mechanism of antinociceptive activity was evaluated using opioid, cholinergic receptor antagonists (naloxone and atropine), or nitric oxide synthase inhibitor (L-NAME). EO and SA presented a central antinociceptive effect (the hot-plate model). In formalin-induced licking response, higher doses of EO and SA also reduced 1st and 2nd phases. None of the antagonists and enzyme inhibitor reversed antinociceptive effects. EO and SA reduced the leukocyte migration into the SAP, and the cytokines tumor necrosis factor and interleukin-1 (TNF-α and IL-1ß, respectively) produced in the exudate. Our results are indicative that EO and SA present peripheral and central antinociceptive and anti-inflammatory effects.
RESUMEN
The melanoma-associated antigen family A (MAGEA) antigens are expressed in a wide variety of malignant tumors but not in adult somatic cells, rendering them attractive targets for cancer immunotherapy. Here we show that a number of cancer-associated MAGEA mutants that undergo proteasome-dependent degradation in vitro could negatively impact their utility as immunotherapeutic targets. Importantly, in pancreatic ductal adenocarcinoma cell models, MAGEA6 suppresses macroautophagy (autophagy). The inhibition of autophagy is released upon MAGEA6 degradation, which can be induced by nutrient deficiency or by acquisition of cancer-associated mutations. Using xenograft mouse models, we demonstrated that inhibition of autophagy is critical for tumor initiation whereas reinstitution of autophagy as a consequence of MAGEA6 degradation contributes to tumor progression. These findings could inform cancer immunotherapeutic strategies for targeting MAGEA antigens and provide mechanistic insight into the divergent roles of MAGEA6 during pancreatic cancer initiation and progression.
Asunto(s)
Antígenos de Neoplasias/fisiología , Autofagia/fisiología , Carcinoma Ductal Pancreático/etiología , Proteínas de Neoplasias/fisiología , Neoplasias Pancreáticas/etiología , Animales , Antígenos de Neoplasias/genética , Autofagia/genética , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Progresión de la Enfermedad , Femenino , Humanos , Ratones , Mutación , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/patología , Complejo de la Endopetidasa Proteasomal/fisiologíaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Schinopsis brasiliensis is a native plant from Brazil, popularly used in folk medicine to relieve pain and treat inflammation. This study evaluated the antinociceptive and anti-inflammatory activities and antioxidant properties of the hydroethanol extract (HEE) and ethyl acetate fraction (EAF) obtained from S. brasiliensis bark. MATERIALS AND METHODS: The HEE and EAF of S. brasiliensis bark (10, 30 and 100mg/kg, p.o.) were evaluated using models of analgaesia (formalin-induced licking and hot-plate models) or inflammation (licking response by formalin-induced and carrageenan-induced cell migration into the subcutaneous air pouch). The antioxidant activities of HEE and EAF (50, 100 and 200µg/ml) were evaluated using the lipoperoxidation method induced in egg yolk by 2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and FeSO4. RESULTS: HEE and EAF presented a central antinociceptive effect (at 100mg/kg dose), increasing the baseline and area under the curve in the hot plate model. EAF (100mg/kg) significantly reduced (p< 0.005) the pain response in the first (45%) and second (35%) phases of the formalin-induced licking model, while HEE (100mg/kg) reduced (38%) only the pain response in the second phase. Regarding anti-inflammatory activity, EAF (100mg/kg) also inhibited the inflammatory process induced by subcutaneous carrageenan injection in the SAP model, reducing the amount of the cytokine TNF-α produced. CONCLUSION: HEE and EAF from S. brasiliensis bark show pharmacological interest because they were able to inhibit the peripheral and central transmission of pain. Our data also suggest that the anti-inflammatory activity caused by EAF exposure occurs through the inhibition of the pro-inflammatory cytokine TNF-α, also reducing the spreading of the inflammatory processes by neutralizing reactive oxygen species, which are by-products in the biosynthesis of pain mediators.
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Anacardiaceae/química , Analgésicos/farmacología , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Animales , Movimiento Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Peroxidación de Lípido/efectos de los fármacos , Ratones , Dimensión del Dolor/efectos de los fármacos , Corteza de la Planta/química , Extractos Vegetales/farmacologíaRESUMEN
Hippo signaling has been recognized as a key tumor suppressor pathway. Here, we perform a comprehensive molecular characterization of 19 Hippo core genes in 9,125 tumor samples across 33 cancer types using multidimensional "omic" data from The Cancer Genome Atlas. We identify somatic drivers among Hippo genes and the related microRNA (miRNA) regulators, and using functional genomic approaches, we experimentally characterize YAP and TAZ mutation effects and miR-590 and miR-200a regulation for TAZ. Hippo pathway activity is best characterized by a YAP/TAZ transcriptional target signature of 22 genes, which shows robust prognostic power across cancer types. Our elastic-net integrated modeling further reveals cancer-type-specific pathway regulators and associated cancer drivers. Our results highlight the importance of Hippo signaling in squamous cell cancers, characterized by frequent amplification of YAP/TAZ, high expression heterogeneity, and significant prognostic patterns. This study represents a systems-biology approach to characterizing key cancer signaling pathways in the post-genomic era.
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Neoplasias/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Secuencia de Bases , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Vía de Señalización Hippo , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Modelos Biológicos , Mutación/genética , Pronóstico , Transducción de Señal/genéticaRESUMEN
Genetic aberrations driving pro-oncogenic and pro-metastatic activity remain an elusive target in the quest of precision oncology. To identify such drivers, we use an animal model of KRAS-mutant lung adenocarcinoma to perform an in vivo functional screen of 217 genetic aberrations selected from lung cancer genomics datasets. We identify 28 genes whose expression promoted tumor metastasis to the lung in mice. We employ two tools for examining the KRAS-dependence of genes identified from our screen: 1) a human lung cell model containing a regulatable mutant KRAS allele and 2) a lentiviral system permitting co-expression of DNA-barcoded cDNAs with Cre recombinase to activate a mutant KRAS allele in the lungs of mice. Mechanistic evaluation of one gene, GATAD2B, illuminates its role as a dual activity gene, promoting both pro-tumorigenic and pro-metastatic activities in KRAS-mutant lung cancer through interaction with c-MYC and hyperactivation of the c-MYC pathway.