RESUMEN
There are different studies that aim to enhance the production of nisin by Lactococcus lactis since its chemical synthesis is not possible. In this study, glutathione (GSH) and pyruvate, which are known to reduce the oxidative stress of cells, have been shown to trigger the production of nisin at both transcriptional and translational levels in L. lactis cells grown under aerobic condition. Presence of GSH and pyruvate caused more nisin yield than the heme-supplemented medium. Moreover, the expression of genes that encode stress-related enzymes were apparently upregulated in the presence of GSH and pyruvate. It can be concluded that GSH and pyruvate contribute to the defense system of L. lactis cells and so that higher biomass was obtained which in turn enhance nisin production. Antioxidant effect of GSH and pyruvate was known; however, their stimulating effect on nisin production was shown for the first time in this study.
Asunto(s)
Antibacterianos/biosíntesis , Glutatión/metabolismo , Hemo/metabolismo , Lactococcus lactis/metabolismo , Nisina/biosíntesis , Ácido Pirúvico/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biomasa , Medios de Cultivo/análisis , Medios de Cultivo/metabolismo , Glutatión/análisis , Hemo/análisis , Lactococcus lactis/genética , Lactococcus lactis/crecimiento & desarrollo , Ácido Pirúvico/análisisRESUMEN
Regulation of the energetic metabolism occurs fundamentally at the cellular level, so analytical strategies must aim to attain single cell resolution to fully embrace its inherent complexity. We have developed methods to utilize a toolset of metabolic FRET sensors for assessing lactate, pyruvate and 2-oxoglutarate levels of Drosophila tissues in vivo by imaging techniques. We show here how the energetic metabolism is altered by hypoxia: While some larval tissues respond to low oxygen levels by executing a metabolic switch towards lactic fermentation, the fat body and salivary glands do not alter their energetic metabolism. Analysis of tumor metabolism revealed that depending on the genetic background, some tumors undergo a lactogenic switch typical of the Warburg effect, while other tumors do not. This toolset allows for developmental and physiologic studies in genetically manipulated Drosophila individuals in vivo.
Asunto(s)
Drosophila melanogaster/metabolismo , Transferencia Resonante de Energía de Fluorescencia/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Animales , Línea Celular Tumoral , Proliferación Celular , Transformación Celular Neoplásica , Drosophila melanogaster/genética , Metabolismo Energético/genética , Glucólisis/fisiología , Hipoxia/metabolismo , Ácidos Cetoglutáricos/análisis , Ácido Láctico/análisis , Oxígeno/metabolismo , Ácido Pirúvico/análisisRESUMEN
Nowdays it is established that ischemic brain damage like ischemic stroke is one of the leading cause of death and disability in the population that assumes relevance development of anti-ischemic drugs. The work studied the anti-hypoxic and anti-ischemic effect of 7 plant extracts. Antihypoxic activity was assessed on models of hypobaric, hypercapnic, histotoxic, hematotoxic hypoxia. Anti-ischemic activity of test-extracts was studied on the focal cerebral ischemia model. Administration of Tagetes patula, Gaillardia pulchella, Sorbaria sorbifolia, Grossularia reclinata, Ribes nigrum, Rubus caesius and Lysimachia punctata extracts contributed to the necrosis zone reduction by 56.6% (p<0.05); 37.3% (p<0.05); 73.2% (p<0.05); 49.4% (p<0.05); 42.5% (p<0.05); 85.5% (p<0.05); 44.2% (p<0.05) and also restored aerobic metabolism in brain tissue. Test - objects increased of the animal lifespan under hypoxia conditions. Based on the data obtained, it is assumed that further studies of North Caucasus flora plant extracts as cerebro-protective agents are promising.
Hoy en diÌa, se ha establecido que el danÌo cerebral isqueÌmico, como el accidente cerebrovascular isqueÌmico, es una de las principales causas de muerte y discapacidad en la poblacioÌn lo cual hace relevante el desarrollo faÌrmacos antiisqueÌmicos. En este trabajo se estudioÌ el efecto antihipoÌxico y antiisqueÌmico de siete extractos de plantas. La actividad antihipoÌxica se evaluoÌ en modelos de hipoxia hipocraÌtica, hipercaÌpnica, histotoÌxica y hematotoÌxica. La actividad antiisqueÌmica de los extractos de prueba se estudioÌ en el modelo de isquemia cerebral focal. La administracioÌn de los extractos de Tagetes patula; Gaillardia pulchella; Sorbaria sorbifolia; Grossularia reclinata; Ribes nigrum; Rubus caesius y Lysimachia punctata contribuyeron a la reduccioÌn de la zona de necrosis en un 56,6% (p<0,05); 37,3% (p<0,05); 73,2% (p<0,05); 49,4% (p<0,05); 42,5% (p<0,05); 85,5% (p<0,05); 44.2% (p<0.05), respectivamente, ademaÌs, de restaurar el metabolismo aeroÌbico en el tejido cerebral. Comparado con el control, se observoÌ un aumento en el tiempo de sobrevida del animal en condiciones de hipoxia. Sobre la base de los interesantes datos obtenidos, se sugiere estudios adicionales de extractos de plantas de la flora del CaÌucaso Norte como agentes protectores del cerebro.
Asunto(s)
Animales , Masculino , Ratones , Ratas , Extractos Vegetales/uso terapéutico , Isquemia Encefálica/tratamiento farmacológico , Hipoxia/tratamiento farmacológico , Ensayo de Inmunoadsorción Enzimática , Adenosina Trifosfato/análisis , Ratas Wistar , Ácido Láctico/análisis , Ácido Pirúvico/análisis , Ratones Endogámicos BALB CRESUMEN
Sulfated and pyruvylated galactans are the major soluble polysaccharides produced by seaweeds of the Bryopsidales. Their backbones have a complex and variable pattern of substitution which, until now, has only been elucidated for a few species. Methods for determination of sulfate and pyruvic acid content, and chemical strategies to determine their position in the galactan chain are outlined here. These methods can also be applied to other sulfated and/or pyruvylated polysaccharides.
Asunto(s)
Chlorophyta/química , Galactanos/química , Ácido Pirúvico/análisis , Algas Marinas/química , Sulfatos/análisis , Conductometría/métodos , Espectroscopía de Resonancia Magnética/métodos , Metilación , Nefelometría y Turbidimetría/métodosRESUMEN
Leptospiral immunoglobulin-like (Lig) proteins are of great interest due to their ability to act as mediators of pathogenesis, serodiagnostic antigens, and immunogens. Purified recombinant LigA protein is the most promising subunit vaccine candidate against leptospirosis reported to date, however, as purified proteins are weak immunogens the use of a potent adjuvant is essential for the success of LigA as a subunit vaccine. In the present study, we compared xanthan pv. pruni (strain 106), aluminium hydroxide (alhydrogel), and CpG ODN as adjuvants in a LigA subunit vaccine preparation. Xanthan gum is a high molecular weight extracellular polysaccharide produced by fermentation of Xanthomonas spp., a plant-pathogenic bacterium genus. Preparations containing xanthan induced a strong antibody response comparable to that observed when alhydrogel was used. Upon challenge with a virulent strain of L. interrogans serovar Copenhageni, significant protection (Fisher test, P < 0.05) was observed in 100%, 100%, and 67% of hamsters immunized with rLigANI-xanthan, LigA-CpG-xanthan, and rLigANI-alhydrogel, respectively. Furthermore, xanthan did not cause cytotoxicity in Chinese hamster ovary (CHO) cells in vitro. The use of xanthan as an adjuvant is a novel alternative for enhancing the immunogenicity of vaccines against leptospirosis and possibly against other pathogens.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Vacunas Bacterianas/inmunología , Leptospirosis/inmunología , Leptospirosis/prevención & control , Polisacáridos Bacterianos/inmunología , Vacunas de Subunidad/inmunología , Animales , Formación de Anticuerpos/efectos de los fármacos , Antígenos Bacterianos/inmunología , Células CHO , Muerte Celular/efectos de los fármacos , Cricetinae , Cricetulus , Modelos Animales de Enfermedad , Femenino , Humedad , Inmunidad Humoral/efectos de los fármacos , Inmunización , Leptospira interrogans/fisiología , Leptospirosis/microbiología , Mesocricetus , Nitrógeno/análisis , Polisacáridos Bacterianos/farmacología , Ácido Pirúvico/análisisRESUMEN
The glucose content in the hemolymph and glycogen content in the digestive gland-gonad complex (DGG) and cephalopedal mass of Biomphalaria glabrata exposed to different parasite doses (5 and 50 miracidia) of Echinostoma paraensei as well as the activity of lactate dehydrogenase were evaluated. HPLC (high-performance liquid chromatography) analyses were also performed to determine the concentrations of four organic acids (oxalic, succinic, pyruvic and lactic) present in the hemolymph of infected and uninfected snails, to better understand the effect of infection on the host's energetic/oxidative metabolism. The snails were dissected 1-4 weeks after infection to collect the hemolymph and separate the tissues. There was alteration in the glycemia of the snails at both parasite doses, with a significant increase of glycemia from of the third week after infection in comparison to the control group. Changes were also observed in the lactate dehydrogenase activity, with increased activity as the infection progressed. In parallel, there was a decrease in the glycogen content in the storage tissues, with a markedly greater reduction in the digestive gland-gonad complex (larval development site) in comparison with the cephalopedal mass. Additionally, the infection by both miracidial doses resulted in an increase of oxalic and lactic acid levels, as well as in a decline of piruvic and succinic acid levels in B. glabrata, thus explaining the reduction of the oxidative decarboxylation rate in the tricarboxylic acid cycle and acceleration of the anaerobic degradation of carbohydrates in the snails, through lactic fermentation, which is essential to ensure energy supply and success of the infection.
Asunto(s)
Biomphalaria/metabolismo , Biomphalaria/parasitología , Echinostoma/fisiología , Aerobiosis , Anaerobiosis , Animales , Cromatografía Líquida de Alta Presión , Cricetinae , Vectores de Enfermedades , Echinostoma/crecimiento & desarrollo , Glucosa/análisis , Glucógeno/análisis , Hemolinfa/química , Histocitoquímica , Interacciones Huésped-Parásitos , L-Lactato Deshidrogenasa/análisis , Ácido Láctico/análisis , Mesocricetus , Ácido Oxálico/análisis , Ácido Pirúvico/análisis , Ácido Succínico/análisis , Factores de TiempoRESUMEN
Response surface methodology (RSM) was employed to study the effects of various medium components on biomass production by Lactobacillus rhamnosus E/N. This strain is commonly used in the pharmaceutical and food industries due to its beneficial effect on the human gut and general health. The best medium composition derived from RSM regression was (in g/l) glucose 15.44, sodium pyruvate 3.92, meat extract 8.0, potassium phosphate 1.88, sodium acetate 4.7, and ammonium citrate 1.88. With this medium composition biomass production was 23 g/l of dry cell weight after 18 h of cultivation in bioreactor conditions, whereas on MRS the yield of biomass was 21 g/l of dry cell weight. The cost of 1 g of biomass obtained on MRS broth was calculated at the level of 0.44 whereas on the new optimal medium it was 25 percent lower. It may be concluded then, that the new medium, being cheaper than the control MRS allows large scale commercial cultivation of the L. rhamnosus strain. This study is of relevance to food industry because the possibility to obtain high yield of bacterial biomass is necessary step in manufacturing of probiotic food.
Asunto(s)
Ácido Pirúvico/análisis , Biomasa , Alimentos , Industria de Alimentos , Lacticaseibacillus rhamnosus/aislamiento & purificación , Probióticos , Suplementos Dietéticos/análisis , Microbiología de Alimentos , Muestras de Alimentos , Metodología como un Tema , Métodos , MétodosRESUMEN
The raw form of garlic and some of its preparations are widely recognized as antiplatelet agents that may contribute to the prevention of cardiovascular disease. Herein, we examined the in-vitro antiaggregatory activity (IVAA) of human blood platelets induced by extracts of garlic samples that were previously heated (in the form of crushed versus uncrushed cloves) using different cooking methods and intensities. The concentrations of allicin and pyruvate, two predictors of antiplatelet strength, were also monitored. Oven-heating at 200 degrees C or immersing in boiling water for 3 min or less did not affect the ability of garlic to inhibit platelet aggregation (as compared to raw garlic), whereas heating for 6 min completely suppressed IVAA in uncrushed, but not in previously crushed, samples. The latter samples had reduced, yet significant, antiplatelet activity. Prolonged incubation (more than 10 min) at these temperatures completely suppressed IVAA. Microwaved garlic had no effect on platelet aggregation. However, increasing the concentration of garlic juice in the aggregation reaction had a positive IVAA dose response in crushed, but not in uncrushed, microwaved samples. The addition of raw garlic juice to microwaved uncrushed garlic restored a full complement of antiplatelet activity that was completely lost without the garlic addition. Garlic-induced IVAA was always associated with allicin and pyruvate levels. Our results suggest that (1) allicin and thiosulfinates are responsible for the IVAA response, (2) crushing garlic before moderate cooking can reduce the loss of activity, and (3) the partial loss of antithrombotic effect in crushed-cooked garlic may be compensated by increasing the amount consumed.