RESUMO
OBJECTIVES: To examine the cross-sectional association between baseline depressive symptoms and the presence of type 2 diabetes (T2D), and its association with glycated hemoglobin (HbA1c) and other metabolic variables, and the prospective association of depressive symptoms and HbA1c after 1 year of follow-up. METHODS: n = 6224 Mediterranean older adults with overweight/obesity and metabolic syndrome (48% females, mean age 64.9 ± 4.9 years) were evaluated in the framework of the PREDIMED-Plus study cohort. Depressive symptoms were assessed using the Beck Depression Inventory-II and HbA1c was used to measure metabolic control. RESULTS: The presence of T2D increased the likelihood of higher levels of depressive symptoms (χ2 = 15.84, p = 0.001). Polynomial contrast revealed a positive linear relationship (χ2 = 13.49, p = 0.001), the higher the depressive symptoms levels, the higher the prevalence of T2D. Longitudinal analyses showed that the higher baseline depressive symptoms levels, the higher the likelihood of being within the HbA1c ≥ 7% at 1-year level (Wald-χ2 = 24.06, df = 3, p < .001, for the full adjusted model). Additionally, depressive levels at baseline and duration of T2D predicted higher HbA1c and body mass index, and lower physical activity and adherence to Mediterranean Diet at 1 year of follow-up. CONCLUSIONS: This study supports an association between T2D and the severity of depressive symptoms, suggesting a worse metabolic control from mild severity levels in the short-medium term, influenced by lifestyle habits related to diabetes care. Screening for depressive symptoms and a multidisciplinary integrative therapeutic approach should be ensured in patients with T2D.
Assuntos
Depressão , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/psicologia , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Feminino , Masculino , Pessoa de Meia-Idade , Seguimentos , Depressão/epidemiologia , Depressão/etiologia , Idoso , Estudos Transversais , Hemoglobinas Glicadas/análise , Estudos Prospectivos , Dieta Mediterrânea , Prevalência , Índice de Massa Corporal , Obesidade/psicologia , Obesidade/epidemiologia , Obesidade/complicações , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/psicologiaRESUMO
OBJECTIVES: We tested the effects of a weight-loss intervention encouraging energy-reduced MedDiet and physical activity (PA) in comparison to ad libitum MedDiet on COVID-19 incidence in older adults. DESIGN: Secondary analysis of PREDIMED-Plus, a prospective, ongoing, multicentre randomized controlled trial. SETTING: Community-dwelling, free-living participants in PREDIMED-Plus trial. PARTICIPANTS: 6,874 Spanish older adults (55-75 years, 49% women) with overweight/obesity and metabolic syndrome. INTERVENTION: Participants were randomised to Intervention (IG) or Control (CG) Group. IG received intensive behavioural intervention for weight loss with an energy-reduced MedDiet intervention and PA promotion. CG was encouraged to consume ad libitum MedDiet without PA recommendations. MEASUREMENTS: COVID-19 was ascertained by an independent Event Committee until December 31, 2021. COX regression models compared the effect of PREDIMED-Plus interventions on COVID-19 risk. RESULTS: Overall, 653 COVID-19 incident cases were documented (IG:317; CG:336) over a median (IQR) follow-up of 5.8 (1.3) years (inclusive of 4.0 (1.2) years before community transmission of COVID-19) in both groups. A significantly lowered risk of COVID-19 incidence was not evident in IG, compared to CG (fully-adjusted HR (95% CI): 0.96 (0.81,1.12)). CONCLUSIONS: There was no evidence to show that an intensive weight-loss intervention encouraging energy-reduced MedDiet and PA significantly lowered COVID-19 risk in older adults with overweight/obesity and metabolic syndrome in comparison to ad libitum MedDiet. Recommendations to improve adherence to MedDiet provided with or without lifestyle modification suggestions for weight loss may have similar effects in protecting against COVID-19 risk in older adults with high cardiovascular risks.
Assuntos
COVID-19 , Doenças Cardiovasculares , Dieta Mediterrânea , Síndrome Metabólica , Humanos , Feminino , Idoso , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/prevenção & controle , Síndrome Metabólica/complicações , Sobrepeso/complicações , Estudos Prospectivos , Doenças Cardiovasculares/etiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/complicações , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/terapia , Estilo de Vida , Redução de PesoRESUMO
Mango leaf tea has been traditionally used by different cultures to reduce inflammation in the body. There is evidence that chronic inflammation increases the risk of cancer. This study investigates the antitumoural effects of pressurized mango leaf extracts on minimally (MCF7) and highly invasive (MDA-MB-231) breast cancer cells as well as on non-tumourigenic cells (MCF10). Extracts showed protective properties against oxidation and cytotoxic effects against breast cancer cell lines, causing minor damage to non-carcinogenic cells. Nonetheless, some selective activity, depending on hormone receptor status, was observed. This was possibly related to the presence of minor compounds. Extracts with high levels of gallotannins showed cytotoxic action against MCF7 cells, while those which had methyl gallate and homomangiferin as common components were more effective against MDA-MB-231 cells. Therefore, the cytotoxic effect of mango leaf extracts might be attributed to the synergistic effect of different polyphenols and not just to mangiferin on its own as the predominant compound in mango leaves.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Mangifera/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Feminino , Humanos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/químicaRESUMO
Olive oil (OO) is the most representative food of the traditional Mediterranean Diet (MedDiet). Increasing evidence suggests that monounsaturated fatty acids (MUFA) as a nutrient, OO as a food, and the MedDiet as a food pattern are associated with a decreased risk of cardiovascular disease, obesity, metabolic syndrome, type 2 diabetes and hypertension. A MedDiet rich in OO and OO per se has been shown to improve cardiovascular risk factors, such as lipid profiles, blood pressure, postprandial hyperlipidemia, endothelial dysfunction, oxidative stress, and antithrombotic profiles. Some of these beneficial effects can be attributed to the OO minor components. Therefore, the definition of the MedDiet should include OO. Phenolic compounds in OO have shown antioxidant and anti-inflammatory properties, prevent lipoperoxidation, induce favorable changes of lipid profile, improve endothelial function, and disclose antithrombotic properties. Observational studies from Mediterranean cohorts have suggested that dietary MUFA may be protective against age-related cognitive decline and Alzheimer's disease. Recent studies consistently support the concept that the OO-rich MedDiet is compatible with healthier aging and increased longevity. In countries where the population adheres to the MedDiet, such as Spain, Greece and Italy, and OO is the principal source of fat, rates of cancer incidence are lower than in northern European countries. Experimental and human cellular studies have provided new evidence on the potential protective effect of OO on cancer. Furthermore, results of case-control and cohort studies suggest that MUFA intake including OO is associated with a reduction in cancer risk (mainly breast, colorectal and prostate cancers).
Assuntos
Dieta Mediterrânea , Saúde , Óleos de Plantas , Envelhecimento/psicologia , Doenças Cardiovasculares/epidemiologia , Doença Crônica , Cognição/fisiologia , Consenso , Diabetes Mellitus/epidemiologia , Expectativa de Vida , Síndrome Metabólica/epidemiologia , Neoplasias/epidemiologia , Obesidade/epidemiologia , Azeite de Oliva , Óleos de Plantas/química , Medição de Risco , Fatores de RiscoRESUMO
Circulating tumor cells (CTCs) in patients with breast cancer can be regarded as the pre-stadium of clinically manifest distant metastases. Here we present results on CTCs determination in peripheral blood (PB) of breast cancer patients in the context of treatment. Ninety-two patients were enrolled onto a prospective, unicenter study and 71 of those subjects are the focus of our analyses. CTC assessment was performed by isolating cytokeratin-positive (CK) cells by immunomagnetic techniques, with further identification by immunocytochemical methods. CTCs were detected in 47 (66%) patients: 35 with primary breast cancer and 12 with metastatic disease. Five (14.3%) of those patients with primary cancer and CTCs showed first disease progression or died. Of those patients with metastatic disease and CTCs before chemotherapy, eleven (91.6%) died. During chemotherapy, >6 CTCs was correlated with a worse prognostic of disease in patients with metastatic disease (p = 0.05). Four weeks after chemotherapy, 59 patients underwent a follow-up assessment. CTCs were detected in 54.2% of those patients. CTCs levels, and not the presence of CTCs alone, was associated with progression free of disease (p = 0.052) and showed borderline significance with overall survival (p = 0.071). The differential prognostic and overall survival showed between patients with and without elevated CTCs before and at the end of chemotherapy, is of special interest in patients without clinical evidence of metastasis.
Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Células Neoplásicas Circulantes/patologia , Adulto , Idoso , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/sangue , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/sangue , Carcinoma Lobular/tratamento farmacológico , Carcinoma Lobular/patologia , Progressão da Doença , Feminino , Humanos , Separação Imunomagnética , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Taxa de SobrevidaRESUMO
The discrepancies among data reported by using olive oil (OO) in humans appear to be due to the great differences between the different OO used. Based on structure/function relationships we have chemically optimized an OO through the rational mixture ("coupage") of several Spanish extra virgin olive oils (methodology "oHo"). Patients with chronic kidney disease (CKD) develop a progressive picture of malnutrition and inflammation that lead them to an elevated risk of cardiovascular disease. In a pilot, randomised trial the nutritional efficacy and safety of "oHo" were evaluated in 32 patients (mean age 60,8 +/- 13,2 years old; 16 women) with CKD (KDIGO stages 4-5) at predialysis. After a 7 days wash out for statins and ACE inhibitors 19 patients had "oHo" at doses of 60 mL/day (20 mL t.i.d) for 30 consecutive days, whilst 13 patients remain as a control group without "oHo". At the end of the study only patients having "oHo" showed significant increases of serum albumin (p<0.05) and not significant increases of total proteins, weight, and BMI. Total cholesterol (p<0.05) and HDL-cholesterol (p<0.01) increased with "oHo". The number of cases with pathologic HOMA-IR in the control group increased from 1 to 2 patients whilst in the "oHo" group decreased from 2 to none. No significant changes of minerals, arterial pressure, hemoglobin, and other parameters related to CKD were seen. After a 30 days follow-up in the "oHo" group all parameters came back to basal ones, excepting for blood pressure that significantly decreased (p<0,05). Tolerance was excellent and constipation significantly diminished (p<0,001) in the "oHo" group. Of importance, none of these biological changes were seen in regular consumers of other conventional olive oils (control group). These intriguing results, seen by the first time, appear to partially satisfy the recent claims ("reverse epidemiology") about the need of a more correct nutrition in CKD patients. However, these data need to be proved in more larger trials as well as in CKD patients under dialysis with harder inflammatory/malnutrition conditions.
Assuntos
Inflamação/dietoterapia , Inflamação/etiologia , Nefropatias/complicações , Desnutrição/dietoterapia , Desnutrição/etiologia , Óleos de Plantas , Doença Crônica , Feminino , Humanos , Inflamação/sangue , Nefropatias/sangue , Masculino , Desnutrição/sangue , Pessoa de Meia-Idade , Azeite de Oliva , Projetos PilotoRESUMO
PURPOSE: Results from an external quality control programme for semen analysis carried out in Spain are analysed. METHODS: Quality control materials were distributed and the following seminal parameters were determined: concentration, total motility, progressive motility, rapid progressive motility, morphology and sperm vitality. The between-laboratories coefficients of variation were assessed on different types of quality control material. RESULTS: The majority of participating laboratories utilised manual versus computer-assisted semen analysis methods. Some between-laboratories coefficients of variation ranges were: 20.8-33.8% for concentration (semen pool suspension); 13.9-19.2% for total motility (videotapes); 54.2-70.2% for sperm morphology (strict criteria using stained smears); and 9.8-41.1% for sperm vitality (stained smears). There was an inverse relation between mean percentage of sperm and coefficients of variation between laboratories for sperm motility, morphology and vitality. CONCLUSIONS: These data highlight the urgent need for improvement in the overall quality of andrology testing.
Assuntos
Técnicas de Laboratório Clínico/normas , Controle de Qualidade , Sêmen/fisiologia , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Humanos , Masculino , EspanhaRESUMO
1. Ageing represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, morbus Parkinson, Alzheimer's disease, vascular dementia, cognitive decline, diabetes and cancer. 2. Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) decreases the risk of cardiovascular disease. 3. The Mediterranean diet, rich in virgin olive oil, improves the major risk factors for cardiovascular disease, such as the lipoprotein profile, blood pressure, glucose metabolism and antithrombotic profile. Endothelial function, inflammation and oxidative stress are also positively modulated. Some of these effects are attributed to minor components of virgin olive oil. Therefore, the definition of the Mediterranean diet should include virgin olive oil. 4. Different observational studies conducted in humans have shown that the intake of monounsaturated fat may be protective against age-related cognitive decline and Alzheimer's disease. 5. Microconstituents from virgin olive oil are bioavailable in humans and have shown antioxidant properties and capacity to improve endothelial function. Furthermore they are also able to modify the haemostasis, showing antithrombotic properties. 6. In countries where the populations fulfilled a typical Mediterranean diet, such as Spain, Greece and Italy, where virgin olive oil is the principal source of fat, cancer incidence rates are lower than in northern European countries. 7. The protective effect of virgin olive oil can be most important in the first decades of life, which suggests that the dietetic benefit of virgin olive oil intake should be initiated before puberty, and maintained through life. 8. The more recent studies consistently support that the Mediterranean diet, based in virgin olive oil, is compatible with a healthier ageing and increased longevity. However, despite the significant advances of the recent years, the final proof about the specific mechanisms and contributing role of the different components of virgin olive oil to its beneficial effects requires further investigations.
Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta Mediterrânea , Neoplasias/prevenção & controle , Óleos de Plantas , Envelhecimento/efeitos dos fármacos , Gorduras Insaturadas na Dieta/farmacologia , Medicina Baseada em Evidências , Humanos , Azeite de Oliva , Estresse Oxidativo/efeitos dos fármacos , Óleos de Plantas/química , Óleos de Plantas/farmacologiaRESUMO
BACKGROUND: A study was undertaken to assess the components of biological variation of seminal parameters in healthy subjects. METHODS: Twenty donor candidates were included in a 10-week follow-up study. Within- and between-subject biological variation, indices of individuality and heterogeneity, coefficient of reliability, critical differences, analytical goals and the lowest value observed with a <5% probability of having a true value less than the World Health Organization (1999) reference value were estimated for the following seminal parameters: concentration, total motility (WHO grades a + b + c), progressive motility (grades a + b), rapid progressive motility (grade a), sperm morphology and vitality. All analysis was performed by a single technician according to WHO 1999 guidelines for routine semen analysis. Analytical variation was assessed on different types of quality control material (frozen straws, sperm suspension, videotape, and slides) and at different (low, medium, high) quality levels. RESULTS: The analytical variation observed depended on the quality control material used and the level of semen quality. Concentration was the semen parameter with highest within- and between-subject variation, and vitality the lowest. Indices of individuality were all <0.7, and coefficients of reliability were high (0.68-0.84). The critical difference for sequential values significant at P < 0.05 for vitality, progressive motility and morphology (34.4, 49.2 and 58.0% respectively) were lower than for concentration (77.8%). CONCLUSIONS: The study results showed that conventional reference values for seminal parameters have little diagnostic value because of their marked individuality, though seminal parameters can be useful for assessing differences in an individual's serial results, in particular of progressive motility, morphology and vitality.
Assuntos
Variação Genética , Sêmen/fisiologia , Adulto , Sobrevivência Celular , Humanos , Masculino , Valores de Referência , Sêmen/citologia , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/citologia , Espermatozoides/fisiologiaRESUMO
BACKGROUND: Apoptotic cells are recognized specifically by macrophages and are cleared rapidly by phagocytosis. However, the recognition mechanisms involved in the clearance of apoptotic cells by macrophages are still not fully understood. Therefore, new methods must be designed to better our understanding of the mechanisms of interaction between macrophages and apoptotic cells. 7-Aminoactinomycin D (7-AAD) is a fluorescent DNA-binding stain usually used as a single agent to detect apoptotic cells by flow cytometry. We propose the use of 7-AAD-stained apoptotic cells as targets for a new flow cytometry phagocytosis assay. METHODS: Murine T-cell lymphoma YAC-1 cells were treated with etoposide to induce apoptosis. Etoposide-treated YAC-1 target cells were stained subsequently with 7-AAD and then coincubated with resident peritoneal macrophages to allow phagocytosis. The samples were analyzed by flow cytometry. Macrophages that had phagocytosed 7-AAD-stained apoptotic cells were identified by their bright red fluorescence and the resulting values were expressed as the percentage of cells. RESULTS: The phagocytic cells appeared as a distinct population characterized by bright fluorescence, which could not be detected in the negative controls. The effects of a phagocytic enhancer (interferon-gamma [IFN-gamma]) or inhibitor (incubation at 4 degrees C) were assessed accurately with this flow cytometric method. CONCLUSIONS: We describe the use of 7-AAD in an assay that is easy and quick to perform. This flow cytometric-based assay allows the quantification of phagocytosis of apoptotic cells by macrophages.
Assuntos
Apoptose , Dactinomicina/análogos & derivados , Citometria de Fluxo/métodos , Corantes Fluorescentes , Fagocitose , Animais , Linfoma de Células T , Camundongos , Células Tumorais Cultivadas/citologiaRESUMO
The resistance of mice to systemic infections caused by Candida albicans is associated with activated splenic macrophages. In addition, there is a correlation between natural killer (NK) cell activation and the resistance to systemic candidiasis. The present study was designed to clarify the role of NK cells in the control of splenic macrophage C. albicans phagocytosis by either depleting NK cells (anti-asialo GM(1) treatment) or maintaining them in an activated state (tilorone treatment) in both immunocompetent BALB/c mice and T-cell-deficient nude mice. The results of the in vitro phagocytosis assays were analyzed by flow cytometry and demonstrate the pivotal role of NK cells in controlling the capacity of splenic macrophages to phagocytose C. albicans. In summary, these data provide evidence that the NK cells are the main inducers of phagocytic activity of splenic macrophages and that they mediate the protection against C. albicans systemic infection.
Assuntos
Candida albicans/imunologia , Candidíase/imunologia , Células Matadoras Naturais/imunologia , Macrófagos/imunologia , Fagocitose , Baço/imunologia , Animais , Candida albicans/patogenicidade , Candidíase/microbiologia , Testes Imunológicos de Citotoxicidade , Gangliosídeo G(M1)/antagonistas & inibidores , Gangliosídeo G(M1)/farmacologia , Imunocompetência , Terapia de Imunossupressão , Ativação Linfocitária , Macrófagos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Baço/citologiaRESUMO
BACKGROUND: Fluorescein isothiocyanate (FITC) is used widely to label the targets used in flow cytometric phagocytosis assays. Unfortunately, the fluorescence intensity of phagocytosed FITC-labeled targets is influenced by changes in intracellular pH level, making quantitative measurements with this fluorophore problematic. We describe the use of SYTOX green nucleic acid stain to measure phagocytosis by flow cytometry. METHODS: Suspensions of isopropyl alcohol-permeabilized Escherichia coli DH5alpha were stained with the SYTOX green dye and then incubated with resident peritoneal macrophages. The samples were analyzed by flow cytometry and phagocytosis was determined by gating the cells. RESULTS: Results are expressed as percentage of phagocyte-associated green fluorescent cells. The validity of the method was shown by the effects of a phagocytosis inhibitor (incubation at 4 degrees C) or enhancer (gamma interferon [IFN- gamma] treatment) being accurately assessed with this assay. CONCLUSIONS: The method described was reproducible and provides an advantageous alternative to the use of FITC to label bacteria for the flow cytometric measurement of target uptake by phagocytic cells.
Assuntos
Escherichia coli/fisiologia , Citometria de Fluxo/métodos , Corantes Fluorescentes , Macrófagos Peritoneais/fisiologia , Fagocitose/fisiologia , Macrófagos Peritoneais/microbiologia , Compostos Orgânicos , Reprodutibilidade dos Testes , Coloração e RotulagemRESUMO
We describe the use of 7-amino-actinomycin D (7AAD) to measure phagocytosis and the opsonizing capacity of serum. Heat-inactivated Candida albicans was previously stained with 7AAD and incubated with resident peritoneal macrophages. The samples were analyzed by flow cytometry and phagocytic cells were identified by their bright red fluorescence. This is a rapid, reproducible and reliable one-step procedure and provides a means of evaluating low levels of phagocytosis.
Assuntos
Candida albicans/imunologia , Dactinomicina/química , Corantes Fluorescentes/química , Proteínas Opsonizantes/análise , Fagocitose , Animais , Células Cultivadas , Dactinomicina/análogos & derivados , Citometria de Fluxo/métodos , Macrófagos Peritoneais/microbiologia , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Alteration of MHC class I molecule expression is a widespread mechanism used by tumor cells to evade T cell responses. It has long been proposed that the origin of these MHC class I-negative or -deficient tumor variants is T cell immune selection. However, there are no experimental or clinical data to substantiate this hypothesis, and this issue is currently the subject of debate. Here we report that an H-2 class I-negative fibrosarcoma tumor clone generated MHC class I-negative spontaneous lung metastases in immunocompetent syngeneic BALB/c mice. Interestingly, the same B9 clone generated MHC class I-positive metastatic nodes, under basal conditions, in athymic nu/nu BALB/c mice. This phenomenon was observed in the metastatic nodules generated after a period of in vivo growth but not in the primary tumors growing locally in the footpad. These findings support the hypothesis that the H-2 phenotype of metastatic nodes is influenced by the T cell repertoire of the host, since in the absence of this T cell pressure (i.e., in nude mice) the metastatic nodes 'recovered' H-2 class I expression. In addition, 2 different phenotypes were found when the metastatic nodules obtained from immunocompetent mice were treated with IFN-gamma. One phenotype, present in 83% of the colonies, was characterized by resistance of the Ld molecule to IFN-gamma induction, due to a deletion involving the Ld gene. The second phenotype (17% of the colonies) was similar to the original B9 clone and was characterized by the response of K, D and L class I genes to IFN-gamma. These data provide evidence that the changes in MHC class I expression during tumor development might not be random but could be predictable.
Assuntos
Fibrossarcoma/genética , Genes MHC Classe I/genética , Neoplasias Pulmonares/genética , Neoplasias Experimentais/genética , Linfócitos T/imunologia , Animais , Separação Celular , Mapeamento Cromossômico , DNA Complementar/metabolismo , Éxons , Fibrossarcoma/imunologia , Citometria de Fluxo , Interferon gama/farmacologia , Neoplasias Pulmonares/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Repetições de Microssatélites , Neoplasias Experimentais/imunologia , Fenótipo , Reação em Cadeia da Polimerase , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/metabolismoRESUMO
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.
Assuntos
Aztreonam/farmacologia , Imunidade/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Monobactamas/farmacologia , Animais , Formação de Anticorpos/efeitos dos fármacos , Imunidade Celular/efeitos dos fármacos , Interleucina-2/biossíntese , Leucócitos Mononucleares/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Baço/imunologiaRESUMO
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.
Assuntos
Candida albicans/imunologia , Candidíase/tratamento farmacológico , Candidíase/imunologia , Indutores de Interferon/uso terapêutico , Tilorona/uso terapêutico , Animais , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Citotoxicidade Imunológica , Indutores de Interferon/farmacologia , Células Matadoras Naturais/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Tilorona/análogos & derivados , Tilorona/farmacologiaRESUMO
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.
Assuntos
Gorduras Insaturadas na Dieta/administração & dosagem , Listeria monocytogenes/imunologia , Listeriose/imunologia , Animais , Peso Corporal , Contagem de Células , Inibidores de Ciclo-Oxigenase/farmacologia , Imunidade Inata , Listeria monocytogenes/isolamento & purificação , Listeria monocytogenes/patogenicidade , Ativação Linfocitária , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Tamanho do Órgão , Fosfolipases/antagonistas & inibidores , Baço/microbiologia , Análise de SobrevidaRESUMO
The immunomodulating properties of antimicrobial drugs may have important implications for clinical practice, particularly for those patients whose immune system has been compromised. In this study, we assessed the influence of different treatments with a beta-lactam antibiotic (imipenem/cilastatin) on several acquired immune responses of BALB/c mice; splenocyte responses to specific mitogens and to sheep red blood cells, IL-2 production and proportions of the different lympho-monocytic populations. Impenem/cilastatin was shown to modify some lymphocyte-associated immune functions and it would be useful to investigate whether immunomodulatory effects also occur in humans.
Assuntos
Quimioterapia Combinada/farmacologia , Imunidade/efeitos dos fármacos , Animais , Cilastatina/farmacologia , Combinação Imipenem e Cilastatina , Combinação de Medicamentos , Imipenem/farmacologia , Interleucina-2/biossíntese , Ativação Linfocitária/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB CRESUMO
The identification of different mechanisms by which tumours escape from the immune system has helped to evaluate the clinical relevance of a variety of phenotypic changes that occur during tumour development. Among them, changes in HLA class I expression play a leading role in the tumour-host environment since HLA class I molecules interact with T lymphocytes for antigen presentation and with NK cells for inhibition/activation of these immune effector cells. Our laboratory has proposed a classification of the altered HLA class I phenotypes frequently found in human tumours, into five major groups. This review focuses on the tumour phenotypes found in primary and metastatic lesions, the molecular mechanisms that give rise to each phenotype and the clinical implications of these findings.
Assuntos
Antígenos de Histocompatibilidade Classe I/fisiologia , Metástase Neoplásica/imunologia , Neoplasias/imunologia , Alelos , Antígenos de Histocompatibilidade Classe I/classificação , Humanos , Fenótipo , Valores de ReferênciaRESUMO
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.