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1.
J Appl Microbiol ; 106(4): 1194-203, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19187147

RESUMEN

AIMS: The ability of concentrated supernatants from Lactobacillus plantarum to produce a disruption of plasma membrane in eukaryotic and prokaryotic cells has been examined. METHODS AND RESULTS: A strain of Lact. plantarum (tolerant to acid and bile salts and resistant to several antibiotics) was used. It inhibited the growth of pathogenic Escherichia coli and L. monocytogenes. Supernatants from Lact. plantarum were concentrated by centrifugation. Either E. coli or HL-60 cells (a human promyelocytic cell line) were treated in the presence of the concentrated supernatants. The effect of concentrated supernatants from Lact. plantarum on E. coli growth demonstrated a bacteriostatic activity and a loss of cell viability measured by sytox green staining. Concentrated supernatants were capable of disturbing plasma membrane in E. coli and of promoting a cytotoxic and lyctic action on HL-60 cells and on human erythrocytes, respectively. CONCLUSIONS: These results suggest that Lact. plantarum release an effective compound responsible for an important effect in the disruption of E. coli plasma membrane and for a cytototoxic activity on promyelocytic leukaemia cells. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first in vitro study about the antimicrobial and biological activities of concentrated supernatants from Lact. plantarum.


Asunto(s)
Antibiosis/fisiología , Escherichia coli/efectos de los fármacos , Células HL-60/efectos de los fármacos , Lactobacillus plantarum/fisiología , Probióticos/farmacología , Membrana Celular/efectos de los fármacos , Recuento de Colonia Microbiana , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Células HL-60/enzimología , Humanos , Hidroliasas/metabolismo
2.
Oncol Rep ; 20(3): 657-62, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18695920

RESUMEN

Normal breast development is controlled by a balance between cell proliferation and apoptosis. The balance between the two parameters is crucial for determining the growth or regression of breast tumours in response to therapies and treatments. Therefore, it is necessary to understand the role of apoptosis in tumour progression. Active caspases participate as essential elements in the execution of apoptotic mechanisms. In the present study, we analysed the activities of caspase-3, -8 and -9 as well as cytochrome c release in N-methyl-nitrosourea (NMU)-induced rat mammary tumours, in order to establish the apoptotic events that occur in tumour growth in this animal model. Forty female virgin Wistar rats were randomly divided into two groups. One group was injected intraperitoneally with three doses of 50 mg/kg body weight of NMU. The control group received the vehicle only. After 122 days of NMU injection, the rats were sacrificed and the tumours were excised and processed. Results showed that in mammary tumours induced by NMU, the apoptotic death receptor-mediated pathway is activated through caspase-3 and -8, but the apoptotic mitochondrial pathway is suppressed through a non-activating process of caspase-9 activity, despite the release of cytochrome c. In conclusion, these findings have demonstrated a suppression of the apoptotic mitochondrial pathway through a non-activating process of caspase-9 activity, despite the release of cytochrome c in mammary tumours induced by NMU. Although the apoptotic death receptor-mediated pathway is activated, it is not enough to maintain the balance between proliferation and apoptosis, and thus determine the overall growth of the tumour.


Asunto(s)
Alquilantes/toxicidad , Apoptosis/fisiología , Caspasa 3/metabolismo , Caspasa 8/metabolismo , Caspasa 9/metabolismo , Neoplasias Mamarias Animales/enzimología , Metilnitrosourea/toxicidad , Animales , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Citocromos c/metabolismo , Femenino , Neoplasias Mamarias Animales/inducido químicamente , Neoplasias Mamarias Animales/patología , Mitocondrias/metabolismo , Ratas , Ratas Wistar , Células Tumorales Cultivadas
3.
Sci Total Environ ; 615: 814-827, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29017125

RESUMEN

A new Circumpolar Active Layer Monitoring (CALM) site was established in 2009 at the Limnopolar Lake watershed in Byers Peninsula, Livingston Island, Antarctica, to provide a node in the western Antarctic Peninsula, one of the regions that recorded the highest air temperature increase in the planet during the last decades. The first detailed analysis of the temporal and spatial evolution of the thaw depth at the Limnopolar Lake CALM-S site is presented here, after eight years of monitoring. The average values range between 48 and 29cm, decreasing at a ratio of 16cm/decade. The annual thaw depth observations in the 100×100 m CALM grid are variable (Variability Index of 34 to 51%), although both the Variance Coefficient and the Climate Matrix Analysis Residual point to the internal consistency of the data. Those differences could be explained then by the terrain complexity and node-specific variability due to the ground properties. The interannual variability was about 60% during 2009-2012, increasing to 124% due to the presence of snow in 2013, 2015 and 2016. The snow has been proposed here as one of the most important factors controlling the spatial variability of ground thaw depth, since its values correlate with the snow thickness but also with the ground surface temperature and unconfined compression resistance, as measured in 2010. The topography explains the thaw depth spatial distribution pattern, being related to snowmelt water and its accumulation in low-elevation areas (downslope-flow). Patterned grounds and other surface features correlate well with high thaw depth patterns as well. The edaphic factor (E=0.05842m2/°C·day; R2=0.63) is in agreement with other permafrost environments, since frozen index (F>0.67) and MAAT (<-2°C) denote a continuous permafrost existence in the area. All these characteristics provided the basis for further comparative analyses between others nearby CALM sites.

4.
Oncogene ; 19(2): 307-14, 2000 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-10645010

RESUMEN

Mitochondrial membrane permeabilization is a critical event in the process leading to physiological or chemotherapy-induced apoptosis. This permeabilization event is at least in part under the control of the permeability transition pore complex (PTPC), which interacts with oncoproteins from the Bcl-2 family as well as with tumor suppressor proteins from the Bax family, which inhibit or facilitate membrane permeabilization, respectively. Here we show that thiol crosslinking agents including diazenedicarboxylic acid bis 5N, N-dimethylamide (diamide), dithiodipyridine (DTDP), or bis-maleimido-hexane (BMH) can act on the adenine nucleotide translocator (ANT), one of the proteins within the PTPC. ANT alone reconstituted into artificial lipid bilayers suffices to confer a membrane permeabilization response to thiol crosslinking agents. Diamide, DTDP, and BMH but not tert-butylhydroperoxide or arsenite cause the oxidation of a critical cysteine residue (Cys 56) of ANT. Thiol modification within ANT is observed in intact cells, isolated mitochondria, and purified ANT. Recombinant Bcl-2 fails to prevent thiol modification of ANT. Concomitantly, a series of different thiol crosslinking agents (diamide, DTDP, and BMH, phenylarsine oxide) but not tert-butylhydroperoxide or arsenite induce mitochondrial membrane permeabilization and cell death irrespective of the expression level of Bcl-2. These data indicate that thiol crosslinkers cause a covalent modification of ANT which, beyond any control by Bcl-2, leads to mitochondrial membrane permeabilization and cell death.


Asunto(s)
Apoptosis , Membranas Intracelulares/enzimología , Translocasas Mitocondriales de ADP y ATP/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Compuestos de Sulfhidrilo/metabolismo , Animales , Línea Celular , Reactivos de Enlaces Cruzados/metabolismo , Humanos , Hibridomas , Sustancias Macromoleculares , Oxidación-Reducción , Permeabilidad , Ratas , Ratas Wistar
5.
FEMS Immunol Med Microbiol ; 32(1): 47-52, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11750222

RESUMEN

Over the past two decades, unsaturated fatty acids have received particular attention due to their ability to suppress immune functions. Nevertheless, suppression of immune functions also involves a reduction of host natural resistance to eliminate the infectious agents. We have analyzed the role of dietary lipids on immune functions in cells cultured with Listeria monocytogenes. Bactericidal efficiency of peritoneal cells from mice fed a fish oil diet against this bacterium was reduced and the incubation of peritoneal cells with polyunsaturated fatty acids led to similar results. The levels of superoxide radicals in the presence of L. monocytogenes increased in cells from mice fed olive oil or fish oil diets. Proteasome activity, a mechanism that participates in T cell activation, was inhibited in all of the dietary groups assayed in the presence of L. monocytogenes, but this inhibition was abolished in the presence of both MG132 (a proteasome inhibitor) and L. monocytogenes. Overall, these results underline the potential role of fatty acids in the modulation of many functions of the immune system.


Asunto(s)
Grasas de la Dieta/administración & dosificación , Inmunidad Innata , Listeria monocytogenes/inmunología , Listeria monocytogenes/patogenicidad , Listeriosis/inmunología , Animales , Peso Corporal , Cisteína Endopeptidasas/metabolismo , Grasas de la Dieta/inmunología , Peroxidación de Lípido , Listeriosis/microbiología , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/microbiología , Ratones , Ratones Endogámicos BALB C , Complejos Multienzimáticos/metabolismo , Complejo de la Endopetidasa Proteasomal , Bazo/citología , Bazo/inmunología , Superóxidos/metabolismo , Timo/citología , Timo/inmunología
6.
FEMS Immunol Med Microbiol ; 29(4): 323-8, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11118914

RESUMEN

Nutritional status may exert a profound effect on immune system functions. Hence, several parameters of immune system are modified by dietary lipid administration, as lymphocyte proliferation, cytokine production, natural killer activity, antigen presentation, etc. Thus, numerous studies have indicated the key role of lipids as immune response modulators. These properties have been applied in the treatment of autoimmune and inflammatory diseases. As a result, the reduction or suppression of immune status due to lipid incorporation promotes an impairment in the ability of host natural response to eliminate infectious microorganisms as bacteria or parasites. In the present review, we analyze the current status about the relationship among dietary lipids, reduction of immune parameters and reduction of host natural response against infectious diseases. Many discrepancies are discussed, although several studies indicate a close association between dietary lipid manipulation and impairment in the elimination of bacteria, viruses or parasites. On the other hand, other studies point out a beneficial effect of dietary lipid manipulation on the host natural response. Future investigations will determine the events involved in the regulation of immune response by fatty acids and their role in the elimination of pathogenic agents.


Asunto(s)
Grasas de la Dieta/administración & dosificación , Inmunidad Celular , Inmunidad Innata , Infecciones/inmunología , Lípidos/fisiología , Grasas Insaturadas en la Dieta/administración & dosificación , Humanos
7.
FEMS Immunol Med Microbiol ; 24(1): 35-42, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10340710

RESUMEN

The effect of nisin on the immune response of mice was studied. Nisin (in the form of the commercial preparation Nisaplin) was incorporated in the diet of experimental mice which were fed for 30, 75 or 100 days. Short-term administration of diets containing Nisaplin induced an increase of both CD4 and CD8 T-lymphocyte cell counts and also a decrease of B-lymphocyte counts. After prolonged diet administration, T-cell counts returned to control levels. Normal levels of B-lymphocytes were also reached after prolonged administration of the lower (but not the higher) Nisaplin concentration. The macrophage/monocyte fraction isolated from peripheral blood became significantly increased after long-term administration (100 days) of Nisaplin-containing diets in a concentration-dependent way. Although the number of peritoneal cells was not affected by the diets, the phagocytic activity of peritoneal cells decreased after prolonged administration of low (but not high) Nisaplin doses.


Asunto(s)
Conservantes de Alimentos , Nisina/inmunología , Animales , Relación CD4-CD8/efectos de los fármacos , Relación CD4-CD8/métodos , Relación Dosis-Respuesta Inmunológica , Citometría de Flujo , Recuento de Leucocitos/efectos de los fármacos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/inmunología , Ratones , Ratones Endogámicos BALB C , Fagocitos/inmunología , Fagocitos/fisiología , Factores de Tiempo
8.
FEMS Immunol Med Microbiol ; 28(4): 283-9, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10891651

RESUMEN

Candida albicans is an increasingly important opportunistic fungal pathogen in immunocompromised patients. Natural killer (NK) cells constitute an important immune effector mechanism and are involved in the response to different pathological disorders. We wished to determine if this immune mechanism is involved in the specific response to C. albicans. Tilorone hydrochloride and related compounds have been described to display antiviral and antitumoral activity, as well as to enhance NK cell activity. In this study, we show the antimicrobial activity of different tilorone analogues and the enhanced resistance of tilorone-treated mice in experimental systemic candidiasis. We also present data suggesting that there is a correlation between NK cell activation and the resistance to experimental systemic candidiasis. Thus, it seems that the immunosurveillance of metastatic spread and the infection by C. albicans share some immune effector mechanisms, in particular activation of NK cells.


Asunto(s)
Candida albicans/inmunología , Candidiasis/tratamiento farmacológico , Candidiasis/inmunología , Inductores de Interferón/uso terapéutico , Tilorona/uso terapéutico , Animales , Bacterias/efectos de los fármacos , Candida albicans/efectos de los fármacos , Citotoxicidad Inmunológica , Inductores de Interferón/farmacología , Células Asesinas Naturales/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Tilorona/análogos & derivados , Tilorona/farmacología
9.
FEMS Immunol Med Microbiol ; 27(2): 127-33, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10640607

RESUMEN

Current understanding based on the effect of dietary lipid manipulation upon immune system function indicates that fatty acids are involved in the modulation of the immune response through different and complex pathways. Reduction of several immune parameters by fatty acid action may be applied in the treatment of diseases characterised by an overactivation of the immune system. As a consequence, a reduction of host resistance against infectious agents has been reported in animals fed dietary lipids. The present study confirms the action of dietary lipids on the survival of mice infected with the pathogenic bacterium Listeria monocytogenes. A significant increase in peritoneal cells from mice fed a hydrogenated coconut oil diet was found, while a significant reduction of bacterial recovery from spleens of these mice was observed in this group. In addition, both eicosanoid and phospholipase inhibitors did not promote any modification of lymphocyte proliferation from mice fed olive oil or fish oil.


Asunto(s)
Grasas Insaturadas en la Dieta/administración & dosificación , Listeria monocytogenes/inmunología , Listeriosis/inmunología , Animales , Peso Corporal , Recuento de Células , Inhibidores de la Ciclooxigenasa/farmacología , Inmunidad Innata , Listeria monocytogenes/aislamiento & purificación , Listeria monocytogenes/patogenicidad , Activación de Linfocitos , Macrófagos Peritoneales/citología , Macrófagos Peritoneales/inmunología , Ratones , Ratones Endogámicos BALB C , Tamaño de los Órganos , Fosfolipasas/antagonistas & inhibidores , Bazo/microbiología , Análisis de Supervivencia
10.
Int J Antimicrob Agents ; 15(3): 193-9, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10926441

RESUMEN

Recent studies have suggested that antibiotics may act as biological response modifiers. In this study we investigated the effect of aztreonam, a monobactam antibiotic, on different parameters of acquired immunity in BALB/c mice. Different dosages of aztreonam injected into mice induced an increase in the lymphoproliferative response to specific mitogens and in the production of interleukin-2 by splenic cells, as well as a decreased response of this immune population to sheep erythrocytes lower total blood cell counts and a lower percentage of monocytes than in untreated mice. These results show a modulatory action of aztreonam on different immune parameters, which is independent of its antimicrobial activity and that could be of interest in human therapy.


Asunto(s)
Aztreonam/farmacología , Inmunidad/efectos de los fármacos , Factores Inmunológicos/farmacología , Monobactamas/farmacología , Animales , Formación de Anticuerpos/efectos de los fármacos , Inmunidad Celular/efectos de los fármacos , Interleucina-2/biosíntesis , Leucocitos Mononucleares/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Bazo/inmunología
11.
Int J Antimicrob Agents ; 13(1): 41-6, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10563409

RESUMEN

The influence of the dose and the duration of treatment with aztreonam, a monocyclic beta-lactam antibiotic, on the natural immune response of mice has been investigated. The results show the effects induced by the antibiotic on several immune parameters were affected by the duration of treatment. Thus, treatment with 28 mg/kg per day of aztreonam over 14 days increased every immune parameter tested, while treatment with 57 mg/kg per day of aztreonam for 7 days only enhanced the natural killer (NK) activity of splenocytes. Since aztreonam does not apparently impair the innate immune response, it might be a suitable therapy for the treatment of patients who are immunosuppressed.


Asunto(s)
Aztreonam/farmacología , Inmunidad Innata/efectos de los fármacos , Monobactamas/farmacología , Animales , Interleucina-1/biosíntesis , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Fagocitos/efectos de los fármacos , Fagocitos/metabolismo
12.
Clin Nutr ; 22(3): 313-9, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12765672

RESUMEN

BACKGROUND & AIMS: Current knowledge of the potential effects that several dietary lipids exert on immune functions indicates that these substances participate actively in the modulation of immune system by which they contribute to the improvement of the conditions of patients suffering from inflammatory disorders. However, long-chain n-3 polyunsaturated fatty acids induce an immunosuppressive status that leads to a reduction of the host natural resistance to infectious agents as well as to an enhancement of oxidative damage. Hence, the present study has been designed to evaluate the effects on the immune system of the antioxidant N-acetyl-L-cysteine (NAC) in mice fed dietary lipids and infected with Listeria monocytogenes. METHODS: Balb/c mice were fed for 4 weeks with diets containing either olive oil (OO, 20% by weight), fish oil (FO, 20% by weight) or hydrogenated coconut oil (HCO, 20% by weight). After dietary lipid administration mice were experimentally infected with L. monocytogenes or treated with NAC (25mg/ml intraperitoneally). RESULTS: NAC at a concentration of 1mM promoted a loss of cell viability, although no differences were observed among the four groups. After injection of NAC in combination with L. monocytogenes, 25% of mice fed a low-fat (LF) diet survived. However, in the groups fed dietary lipids no effect on survival of mice was found. NAC participated in the reduction of superoxide anion generation measured with nitroblue tetrazolium (NBT) in the group fed a FO diet. Finally, NAC reduced the recovery of L. monocytogenes from spleen of mice fed diets containing LF or HCO. CONCLUSIONS: On the basis of these results, we can confirm that the administration of NAC improves survival in mice fed LF diet, whereas a reduction in the generation of superoxide radicals was measured in mice fed a FO diet and infected with L. monocytogenes. Similarly, bacterial recovery was diminished in mice fed diets containing LF or HCO. Hence, these data reveal a beneficial effect of NAC in mice fed LF or HCO and a detrimental action of this antioxidant in mice fed diets containing FO or OO.


Asunto(s)
Acetilcisteína/farmacología , Grasas de la Dieta/administración & dosificación , Depuradores de Radicales Libres/farmacología , Listeria monocytogenes/fisiología , Listeriosis/inmunología , Acetilcisteína/administración & dosificación , Animales , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , Adhesión Bacteriana/efectos de los fármacos , Depuradores de Radicales Libres/administración & dosificación , Peroxidación de Lípido/efectos de los fármacos , Listeria monocytogenes/crecimiento & desarrollo , Listeria monocytogenes/inmunología , Listeriosis/epidemiología , Masculino , Ratones , Ratones Endogámicos BALB C , Distribución Aleatoria , Especies Reactivas de Oxígeno/metabolismo , Bazo/citología , Bazo/microbiología
13.
Anticancer Res ; 21(4A): 2697-702, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11724342

RESUMEN

It is generally assumed that unsaturated fatty acids are important biological mediators that may be applied in the treatment of patients suffering from autoimmune disorders, in the modulation of tumorigenic processes or in the induction or inhibition of apoptosis. In this study, mice divided into three groups were fed dietary lipids; olive oil (20% w/w), fish oil (20% w/w) or hydrogenated coconut oil (20% w/w) for four weeks. Then, survival percentage, natural killer (NK) cell activity and lipid peroxidation were measured after murine lymphoma (LSTRA) transplantation. Survival percentage showed a reduced resistance to LSTRA tumor in mice fed fish oil diet and generaly loss of NK cell activity was observed after lymphoma transplantation. Lipid peroxidation from mice fed dietary lipids was measured in the presence of both phospholipase and cyclooxygenase inhibitors. In general, the data contained in this paper point to a detrimental effect caused by dietary lipids in mice transplanted with a lymphoma.


Asunto(s)
Grasas de la Dieta/efectos adversos , Células Asesinas Naturales/inmunología , Linfoma/inmunología , Animales , Aceite de Coco , Inhibidores de la Ciclooxigenasa/farmacología , Citotoxicidad Inmunológica/efectos de los fármacos , Citotoxicidad Inmunológica/inmunología , Grasas de la Dieta/inmunología , Inhibidores Enzimáticos/farmacología , Aceites de Pescado/efectos adversos , Aceites de Pescado/inmunología , Células Asesinas Naturales/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Peroxidación de Lípido/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Trasplante de Neoplasias/inmunología , Aceite de Oliva , Cavidad Peritoneal/citología , Fosfolipasas/antagonistas & inhibidores , Aceites de Plantas/efectos adversos , Quinacrina/farmacología , Zimosan/farmacología
14.
J Antibiot (Tokyo) ; 50(6): 502-8, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9268007

RESUMEN

The imipenem/cilastatin constitutes a broad spectrum beta-lactam antibiotic formulation, especially used in pre and post-operatory treatments for transplanted or drug-immunosuppresed patients. The effect of the dose and the duration of the treatment with imipenem/cilastatin on some parameters of natural immunity in BALB/c mice were examined. The treatment by intraperitoneal route with 1 or 2 g/70 kg/day during 7 days did not alter significantly the parameters tested, whereas the greater dose used (4 g/70 kg/day) had an inhibitory effect on peritoneal cell counts and phagocytic activity, as well as it caused an increase on IL-1 production and natural killer activity. The greater stimulating effect of innate immunity was obtained with the lowest imipenem/cilastatin dose used (0.5 g/70 kg/day). Since this antibiotic apparently does not impair the studied innate immune responses at 1 or 2 g/70 kg/day, it seems to be especially suited for the therapy of systemic bacterial infections in immunocompromised patients.


Asunto(s)
Antibacterianos/farmacología , Quimioterapia Combinada/farmacología , Inmunidad Innata/efectos de los fármacos , Animales , Recuento de Células/efectos de los fármacos , Cilastatina/farmacología , Combinación Cilastatina e Imipenem , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Imipenem/farmacología , Interleucina-2/biosíntesis , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Leucocitos/efectos de los fármacos , Leucocitos/inmunología , Leucocitos/metabolismo , Macrófagos Peritoneales/citología , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Cavidad Peritoneal/citología , Fagocitosis/efectos de los fármacos
15.
Folia Biol (Praha) ; 48(3): 89-95, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12118728

RESUMEN

In recent years, it has been demonstrated that certain fatty acids are involved in the modulation of immune system functions. The mechanisms responsible for these effects are not fully elucidated, but many hypotheses have described numerous changes in the cell functionality as the main factors capable of altering the immune functions. In the present investigation, we have analysed the potential effects of FFA on cell viability, production of superoxide radicals or proteasome activity in assays in vitro. Thus, different FFA, such as OA, EPA or SA have been incorporated to cellular cultures at a concentration of 100 microM. Phospholipase, cyclooxygenase or lipooxygenase inhibitors abolished the loss of thymocyte viability exerted by EPA, the most immunosuppressive fatty acid. Similarly, measurement of the oxidative process by NBT reduction in cells treated with EPA was markedly increased. Nevertheless, the proteasome activity as a mechanism that participates in T-cell activation was not modified by direct action of the different fatty acids on the in vitro cultures. Overall, these results underline the differential role of several fatty acids (particularly long-chain n-3 polyunsaturated fatty acids) in order to modulate many functions of the immune system.


Asunto(s)
Ácidos Grasos Omega-3/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Cisteína Endopeptidasas/metabolismo , Ácidos Grasos Omega-3/metabolismo , Ratones , Ratones Endogámicos BALB C , Complejos Multienzimáticos/metabolismo , Fosfolipasas/antagonistas & inhibidores , Prostaglandina-Endoperóxido Sintasas/metabolismo , Complejo de la Endopetidasa Proteasomal , Superóxidos/metabolismo
16.
Folia Biol (Praha) ; 44(3): 117-21, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-10730853

RESUMEN

A mixture of Ficoll 400 and sodium diatrizoate (Hypaque) at a density of 1.077 g/ml has been used to isolate the mononuclear cells from the remaining haematic cells. A simple, inexpensive and classical method was established to obtain substantially erythrocyte-free polymorphonuclear cell preparations from mouse peripheral blood, using a mixture of the same substances but at a density of 1.119 g/ml. This method along with that at a density of 1.077 g/ml allows two cellular bands to appear which contain mononuclear and polymorphonuclear (PMN) cells, respectively. Using this method, the counts of monocytes isolated from peripheral blood are significantly greater than those obtained by a one-step Ficoll-Hypaque procedure. On the contrary, the counts of PMN cells are significantly smaller than when sedimentation in dextran (6% solution) is used after gradient centrifugation. In this paper, chemiluminescence assay has been used to analyze the possible variations in phagocytic activity of cells isolated by both procedures, since it appears to be one of the most sensitive methods available for this purpose. The results obtained show a slightly greater activation in monocytes and PMN cells isolated by one-step Ficoll-Hypaque procedure, in comparison with another method which uses both Ficoll-Hypaque 1077 and Ficoll-Hypaque 1119, although statistical differences were not significant.


Asunto(s)
Separación Celular/métodos , Fagocitos/citología , Animales , Centrifugación por Gradiente de Densidad , Diatrizoato , Ficoll , Técnicas In Vitro , Mediciones Luminiscentes , Ratones , Ratones Endogámicos BALB C , Monocitos/citología , Monocitos/fisiología , Neutrófilos/citología , Neutrófilos/fisiología , Fagocitos/fisiología , Fagocitosis
17.
J Nutr Sci Vitaminol (Tokyo) ; 44(1): 57-67, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9591234

RESUMEN

Previous studies have demonstrated that dietary lipid manipulation may modify immune response by affecting lymphocyte proliferation, phagocytosis, cytokine production, etc. In this paper, we investigated the effect of olive oil (OO) on the phagocytic activity and cytokine production by murine peritoneal cells. These results were compared with those obtained from mice fed diets containing sunflower oil (SO) or hydrogenated coconut oil (HCO). Balb/c mice were divided into three groups and fed diets containing 15% by weight of either OO, SO or HCO for 5, 15, 30, 60 or 90 d. Phagocytic activity and interleukin-1 (IL-1) production were increased in OO-fed mice as compared to the other groups. On the contrary, no significant differences were observed in the levels of tumor necrosis factor (TNF) production, although the levels of this cytokine were slightly increased in mice fed the OO diet. These observations suggest that OO is able to modify the immune response and therefore, it may be used as an immunomodulatory agent.


Asunto(s)
Citocinas/biosíntesis , Grasas Insaturadas en la Dieta/administración & dosificación , Ácidos Grasos/administración & dosificación , Peritoneo/citología , Peritoneo/inmunología , Fagocitosis , Animales , Peso Corporal , Recuento de Células , Interleucina-1/biosíntesis , Ratones , Ratones Endogámicos BALB C , Aceite de Oliva , Aceites de Plantas , Factor de Necrosis Tumoral alfa/biosíntesis
18.
Nutr Hosp ; 19(6): 333-40, 2004.
Artículo en Español | MEDLINE | ID: mdl-15672648

RESUMEN

Several dietary lipids are capable of exerting an immunosupressor effect. This action may have undiserable effects on the host immune resistance to infectious diseases. The purpose of the present study was to determinate the immune status of mice fed dietary lipids and experimentally infected with a virulent strain of Listeria monocytogenes. Balb/c mice were divided into four groups and were fed with their respective diet: low fat diet (LF, 20%), olive oil diet (OO, 20%), fish oil diet (FO, 20%) and hydrogenated coconut oil (HCO, 20%). Mice were fed for four weeks and infected with L. monocytogenes by endovenous route. Results have shown a survival reduction in mice fed a diet containing FO, as well as a significant increase in the number of viable bacteria from spleen. In addition, we have observed an increase in the bactericidal activity in peritoneal cells from OO group, although the invasion of L. monocytogenes in cells from this group was larger. Finally, a significant reduction of lymphocyte proliferation was observed in the group fed an FO diet, whereas natural killer (NK) cell activity was not modified. These results indicate that dietary lipids constituted by polyunsaturated n-3 fatty acids reduce the murine immune resistance, whereas a diet constituted by OO-does not exert an immunosuppressor effect as relevant as FO diet, and it does not reduce the immune resistance leading to an efficient L. monocytogenes elimination.


Asunto(s)
Grasas de la Dieta/administración & dosificación , Sistema Inmunológico/fisiología , Listeria monocytogenes/patogenicidad , Listeriosis/inmunología , Animales , Actividad Bactericida de la Sangre/inmunología , Aceite de Coco , Aceites de Pescado/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Modelos Animales , Aceite de Oliva , Aceites de Plantas/administración & dosificación
19.
An Sist Sanit Navar ; 32(3): 385-96, 2009.
Artículo en Español | MEDLINE | ID: mdl-20094099

RESUMEN

BACKGROUND: Selective biopsy of the sentinel ganglion (SBSG) has replaced axillary lymphadectomy (AL) as the procedure of choice in staging breast cancer in its initial stages and in clinically negative axilla. The aim of this study is to compare global event-free survival of those patients subjected to SBSG followed by AL, during the period of validation of the technique, with respect to those subjected to SBSG and AL if the sentinel ganglion (SG) showed metastasis. METHODS: One hundred and forty-eight patients were included, 81 belonging to the period of validation and 67 to the clinical application group. Radiocoloid was administered intraperitumorally, obtaining images up until the visualisation of the SG; its identification and extirpation were carried out subsequently in the surgical intervention. RESULTS: The efficacy of the technique in the validation group was 92.5%, sensitivity was 95.6% and the rate of false negatives was 4%. Of the 81 patients, 75 are free of disease (92.6%). Of the 67 patients belonging to the clinical application group, 63 (94%) are free of disease. No patient has presented axillary ganglion recurrence. CONCLUSION: In the validation of the technique we obtained values that fall within the demands of generally accepted quality. With an average follow up of 6 years we did not observe axillary ganglion recurrence in any of the two groups. There is no statistically significant difference in global and event free survival between the two groups.


Asunto(s)
Neoplasias de la Mama/patología , Escisión del Ganglio Linfático , Biopsia del Ganglio Linfático Centinela , Adulto , Anciano , Anciano de 80 o más Años , Axila , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios Retrospectivos
20.
Immunol Cell Biol ; 78(1): 31-9, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10651927

RESUMEN

Dietary lipid manipulation may affect a great number of immune parameters, such as lymphocyte proliferation, cytokine synthesis, natural killer (NK) cell activity, phagocytosis and so on. The immunomodulation induced by dietary fatty acids may be applied in the amelioration of inflammatory disorders, such as autoimmune diseases. However, the mechanisms that participate in these processes are still poorly understood. It is probable that modulation of immune system by fatty acids of the diet may occur by alteration of membrane fluidity, lipid peroxide formation, eicosanoid production or regulation of gene expression. However, recent studies have reported the effects of several free fatty acids on apoptosis induction of in vitro cultures. In fact, a possible explanation of the effects that fatty acids promote on the immune system cells could be associated with an apoptotic process performed in an irreversible way. In vivo studies have demonstrated the ability of fatty acids to alter the survival of animals fed diets containing oils and infected with a pathogenic bacterium. Experimental infection in animals fed dietary lipids produces a modification of resistance to micro-organisms. The present review analyses all of these parameters that dietary fatty acids are capable of altering in order to modify the immune response. Further studies will be needed to establish the mechanisms involved in immune system regulation, reduction of symptoms derived from autoimmune pathologies and so on.


Asunto(s)
Grasas de la Dieta/farmacología , Ácidos Grasos/farmacología , Sistema Inmunológico/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Infecciones Bacterianas/inmunología , Citocinas/biosíntesis , Eicosanoides/biosíntesis , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Técnicas In Vitro , Inflamación/inmunología , Células Asesinas Naturales/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Activación de Linfocitos/efectos de los fármacos , Fluidez de la Membrana/efectos de los fármacos , Fagocitosis/efectos de los fármacos , Virosis/inmunología
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