RESUMO
Increased oxidative stress may contribute to cancer anorexia, which could be ameliorated by antioxidant supplementation. methylcholanthrene (MCA) sarcoma-bearing Fisher rats were studied. After tumour inoculation, rats were randomly assigned to standard diet (CTR group, n = 6), or to an antioxidant-enriched diet (AOX group, n = 8). Eight more rats (STD-AOX group) switched from standard to antioxidant diet when anorexia developed. At the end of the study, food intake (FI, g/d), body weight and tumour weight (g) were recorded, and plasma samples were obtained. On day 16, anorexia has appeared only in CTR and STD-AOX animals. At the end of the study, FI in AOX animals was still higher than in the other groups (p = 0.08). No differences in body and tumour weights were observed among groups. However, hydrogen peroxide and interleukin-1ß levels were significantly reduced only in AOX rats. Data obtained suggest that early antioxidant supplementation improves cancer anorexia, ameliorates oxidative stress and reduces inflammation.
Assuntos
Anorexia/tratamento farmacológico , Antioxidantes/uso terapêutico , Suplementos Nutricionais , Ingestão de Energia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sarcoma/complicações , Animais , Anorexia/sangue , Anorexia/etiologia , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/uso terapêutico , Peso Corporal/efeitos dos fármacos , Dieta , Modelos Animais de Doenças , Esquema de Medicação , Peróxido de Hidrogênio/sangue , Interleucina-1beta/sangue , Masculino , Metilcolantreno , Distribuição Aleatória , Ratos Endogâmicos F344 , Sarcoma/sangue , Sarcoma/induzido quimicamente , Vitamina E/administração & dosagem , Vitamina E/uso terapêuticoRESUMO
BACKGROUND: Community-acquired pneumonia (CAP) is complicated by cardiovascular events as myocardial infarction and stroke but the underlying mechanism is still unclear. We hypothesized that endothelial dysfunction may be implicated and that endotoxemia may have a role. METHODS: Fifty patients with CAP and 50 controls were enrolled. At admission and at discharge, flow-mediated dilation (FMD), serum levels of endotoxins and oxidative stress, as assessed by serum levels of nitrite/nitrate (NOx) and isoprostanes, were studied. RESULTS: At admission, a significant difference between patients with CAP and controls was observed for FMD (2.1±0.3 vs 4.0±0.3%, p<0.001), serum endotoxins (157.8±7.6 vs 33.1±4.8pg/ml), serum isoprostanes (341±14 vs 286±10 pM, p=0.009) and NOx (24.3±1.1 vs 29.7±2.2µM). Simple linear correlation analysis showed that serum endotoxins significantly correlated with Pneumonia Severity Index score (Rs=0.386, p=0.006). Compared to baseline, at discharge CAP patients showed a significant increase of FMD and NOx (from 2.1±0.3 to 4.6±0.4%, p<0.001 and from 24.3±1.1 to 31.1±1.5µM, p<0.001, respectively) and a significant decrease of serum endotoxins and isoprostanes (from 157.8±7.6 to 55.5±2.3pg/ml, p<0.001, and from 341±14 to 312±14 pM, p<0.001, respectively). Conversely, no changes for FMD, NOx, serum endotoxins and isoprostanes were observed in controls between baseline and discharge. Changes of FMD significantly correlated with changes of serum endotoxins (Rs=-0.315; p=0.001). CONCLUSIONS: The study provides the first evidence that CAP is characterized by impaired FMD with a mechanism potentially involving endotoxin production and oxidative stress.
Assuntos
Infecções Comunitárias Adquiridas/fisiopatologia , Endotélio Vascular/fisiopatologia , Isoprostanos/sangue , Lipopolissacarídeos/sangue , Nitratos/sangue , Nitritos/sangue , Pneumonia/fisiopatologia , Vasodilatação , Idoso , Idoso de 80 Anos ou mais , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiopatologia , Infecções Comunitárias Adquiridas/sangue , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Pneumonia/sangue , Estudos Prospectivos , UltrassonografiaRESUMO
BACKGROUND & AIMS: In hospitalized patients, lack of appetite, i.e., disease-associated anorexia, is the main factor determining insufficient food intake and weight loss, which in turn increase morbidity and mortality. Controversies exist on which tool should be preferred when diagnosing anorexia. Aim of the study was to evaluate in hospitalized medical patients, the performance of 4 different tools [i.e., self-assessment of appetite, FAACT-ESPEN score, visual analog scale (VAS), and the Anorexia Questionnaire (AQ)] in assessing disease-associated anorexia and predicting nutritional and clinical variables. MATERIALS AND METHODS: Hospitalized patients consecutively admitted to the Internal Medicine ward at our institution were considered. After informed consent was obtained, patients were asked to self-assess their appetite vs the previous month. The VAS, the FAACT-ESPEN score and the Anorexia Questionnaire were also submitted. Food intake immediately following the interview was recorded. Nutritional (i.e., body weight, height), functional (i.e., handgrip strength) and clinical variables (i.e., length of stay) were registered upon admission and before discharge. RESULTS: We studied 105 patients (74M:31F; 66.2 ± 16.3 yrs). The prevalence of anorexia as assessed by patients' self assessment, FAACT-ESPEN score, and the Anorexia Questionnaire was 23%, 10% and 48%, respectively. VAS did not show any correlation with food intake. Anorexic patients as identified by the self assessment of appetite showed reduced food intake and weaker handgrip strength than non-anorexic. The FAACT-ESPEN score correlated with body weight, food intake and handgrip strength, but was not related with length of stay. Anorexic patients as identified by the Anorexia Questionnaire showed reduced food intake, lower body weight, weaker handgrip strength and longer hospital stay than non-anorexic patients. DISCUSSION: The prevalence of anorexia significantly varies according to the diagnostic tool used. Except for VAS, all the tested tools identify patients with impaired nutritional and functional variables. However, only the Anorexia Questionnaire identifies patients with longer hospital stay. Our results suggest that in clinical practice, modification of appetite reflects different underlying mechanisms whose impacts on clinical outcome measures may differ. Therefore, an ideal anorexia assessment tool does not appear to exist, but it should be chosen according to the outcome measures to be assessed (i.e., Anorexia Questionnaire to predict length of stay).