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BACKGROUND & AIMS: The liver is the main organ regulating metabolism. In spite of that, few studies examine liver metabolism in cachexia, a wasting syndrome associated with increased morbidity and mortality in cancer. Cachexia induces major metabolic disruption, inflammation and fat and lean mass loss. We have previously shown impairment of hepatic lipid metabolism in cancer cachexia that contributes to the aggravation of the symptoms. The present study addresses the effects of Conjugated Linoleic Acid supplementation upon liver lipid metabolism in cachectic rats. METHODS: Male Wistar rats were randomly assigned to control groups (C) receiving 0.9 NaCl (Placebo CP); or to groups supplemented with sunflower oil (CSF), supplemented with CLA (CCLA), or still, to tumour bearing animals (T) receiving NaCl (TP), sunflower oil (TSF), or CLA (TCLA). Supplementation (0.5 ml) by gavage was carried out for 14 days. Body weight, dietary intake, glucose, cholesterol and triacylglycerol plasma content, liver glycogen and triacylglycerol content and mRNA expression of liver carnitine palmitoyltransferase I and II (CPT I and II), as well as microsomal triglyceride transfer protein (MTP), liver fatty acid-binding protein (L-FABP), peroxisome proliferator-activated receptor-alpha (PPAR-alpha), and apolipoprotein B (apoB), were assessed. RESULTS: Liver CPT II activity was reduced in all groups, when compared with CP. Hepatic mRNA expression of MTP, apoB and FABP was reduced in TCLA, when compared with all groups. TCLA also presented increased hepatic and plasma triacylglycerol content, when compared with all T groups. Adipose tissue-derived inflammatory factors were assessed. No differences among the groups were observed in regard to Retro Peritoneal Adipose Tissue cytokine (IL-1ß, IL-6, and TNF-α) protein content and expression, with the exception of IL-10 in tumour-bearing animals. In the Epididymal Adipose Tissue, the inflammatory cytokines were augmented in TCLA, compared with all other groups. CONCLUSION: CLA supplementation fails to promote the re-establishment of hepatic lipid metabolism in tumour-bearing animals, and therefore is not recommended in cancer-related cachexia.
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Caquexia , Ácidos Linoleicos Conjugados , Metabolismo de los Lípidos/efectos de los fármacos , Hígado , Neoplasias/complicaciones , Tejido Adiposo/química , Tejido Adiposo/metabolismo , Animales , Caquexia/etiología , Caquexia/metabolismo , Suplementos Dietéticos , Inflamación/inducido químicamente , Inflamación/metabolismo , Ácidos Linoleicos Conjugados/efectos adversos , Ácidos Linoleicos Conjugados/farmacología , Lípidos/análisis , Hígado/química , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratas , Ratas WistarRESUMEN
Chia seed (Salvia hispanica L.) contains high amounts of n-3 α-linolenic acid (ALA) and has been associated with many health benefits. The aim of the present study was to evaluate the AIN-93 diet supplemented by chia flour on cancer-cachexia development and tissues inflammatory response. Wistar rats at 30 days old were treated with control diet or diet supplemented with chia flour for eight weeks. After this period, half of the animals in each diet group were inoculated with Walker 256 tumor cells. On the 14th day after tumor inoculation, the animals were euthanized and white adipose tissue depots, liver, gastrocnemius muscle, and tumor were removed. The tumor weight was higher and IL-10 content was lower in chia flour group. The tumor bearing did not modify the cytokines content in gastrocnemius muscle, retroperitoneal and epididymal adipose tissue, however, it decreased IL-1ß and TNF-α content in liver, and IL6R and IL-10R protein content in mesenteric adipose tissue. In conclusion, our results demonstrated that supplementation with chia flour did not prevent the tumor bearing effects in Walker 256 model.
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Carcinoma 256 de Walker/patología , Suplementos Dietéticos , Inflamación/metabolismo , Salvia , Tejido Adiposo/metabolismo , Animales , Peso Corporal , Carcinoma 256 de Walker/dietoterapia , Citocinas/metabolismo , Harina/análisis , Prueba de Tolerancia a la Glucosa , Inflamación/dietoterapia , Lípidos/análisis , Masculino , Trasplante de Neoplasias , Tamaño de los Órganos , Proteínas/análisis , Ratas WistarRESUMEN
PURPOSE OF REVIEW: Cancer anorexia is a negative prognostic factor and is broadly defined as the loss of the interest in food. However, multiple clinical domains contribute to the phenotype of cancer anorexia. The characterization of the clinical and molecular pathophysiology of cancer anorexia may enhance the efficacy of preventive and therapeutic strategies. RECENT FINDINGS: Clinical trials showed that cancer anorexia should be considered as an umbrella encompassing different signs and symptoms contributing to appetite disruption in cancer patients. Loss of appetite, early satiety, changes in taste and smell are determinants of cancer anorexia, whose presence should be assessed in cancer patients. Interestingly, neuronal correlates of cancer anorexia-related symptoms have been revealed by brain imaging techniques. SUMMARY: The pathophysiology of cancer anorexia is complex and involves different domains influencing eating behavior. Limiting the assessment of cancer anorexia to questions investigating changes in appetite may impede correct identification of the targets to address.
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Anorexia/etiología , Hipotálamo/fisiopatología , Modelos Neurológicos , Neoplasias/fisiopatología , Trastornos del Olfato/fisiopatología , Trastornos del Gusto/fisiopatología , Animales , Anorexia/diagnóstico , Anorexia/prevención & control , Regulación del Apetito , Humanos , Hipotálamo/diagnóstico por imagen , Neoplasias/diagnóstico , Neuroimagen , Trastornos del Olfato/diagnóstico por imagen , Trastornos del Olfato/etiología , Trastornos del Olfato/terapia , Pronóstico , Respuesta de Saciedad , Trastornos del Gusto/diagnóstico por imagen , Trastornos del Gusto/etiología , Trastornos del Gusto/terapiaRESUMEN
Carbon tetrachloride (CCl4) is a potent hepatotoxin, capable of generating free radicals that lead to oxidative stress and the inflammation process. Pequi almond oil (PAO) has been reported to possess unsaturated fatty acid and antioxidant compounds related to beneficial effects on oxidation and inflammatory conditions. The present study was undertaken to evaluate the hepatoprotective effects of handmade and coldpressed PAO on CCl4-induced acute liver injury. The possible mechanisms underlying the effect on liver injury enzymes, histopathological parameters, lipid profile, lipid peroxidation, and antioxidant and detoxification defense systems, as well as inflammatory parameters, were determined. Rats treated with PAO (3 or 6 mL/kg) for 21 days before CCl4 induction (3 mL/kg, 70%) showed significantly decreased levels of alanine aminotransferase and aspartate aminotransferase, milder hepatic lesions and higher levels of serum high-density lipoprotein compared to CCl4 group. Moreover, PAO enhanced antioxidant capacity by increasing hepatic glutathione peroxidase and glutathione reductase enzyme activities, as well as reducing circulating concentrations of leptin and inflammatory mediators such as interleukin-6, leukotrienes -4 and -5 and the tumor necrosis factor receptor. In summary, PAO, especially cold-pressed oil, attenuated the CCl4-induced alterations in serum and hepatic tissue in rats due to its antioxidant and anti-inflammatory properties.
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Antiinflamatorios/farmacología , Antioxidantes/farmacología , Tetracloruro de Carbono/toxicidad , Inflamación/prevención & control , Hígado/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Aceites de Plantas/farmacología , Enfermedad Aguda , Animales , Peroxidación de Lípido/efectos de los fármacos , Hígado/lesiones , Hígado/patología , Masculino , Aceites de Plantas/química , Ratas , Ratas WistarRESUMEN
Nonalcoholic fatty liver disease has been considered the hepatic manifestation of obesity. It is unclear whether supplementation with green tea extract rich in epigallocatechin-3-gallate (EGCG) influences the activity of mitochondrial respiratory chain complexes and insulin resistance in the liver. EGCG regulated hepatic mitochondrial respiratory chain complexes and was capable of improving lipid metabolism, attenuating insulin resistance in obese mice. Mice were divided into four groups: control diet+water (CW) or EGCG (CE) and hyperlipidic diet+water (HFW) or EGCG (HFE). All animals received water and diets ad libitum for 16 weeks. Placebo groups received water (0.1 ml/day) and EGCG groups (0.1 ml EGCG and 50 mg/kg/day) by gavage. Cytokines concentrations were obtained by ELISA, protein expression through Western blotting and mitochondrial complex enzymatic activity by colorimetric assay of substrate degradation. HFW increased body weight gain, adiposity index, retroperitoneal and mesenteric adipose tissue relative weight, serum glucose, insulin and Homeostasis Model Assessment of Basal Insulin Resistance (HOMA-IR); glucose intolerance was observed in oral glucose tolerance test (OGTT) as well as ectopic fat liver deposition. HFE group decreased body weight gain, retroperitoneal and mesenteric adipose tissue relative weight, HOMA-IR, insulin levels and liver fat accumulation; increased complexes II-III and IV and malate dehydrogenase activities and improvement in glucose uptake in OGTT and insulin sensitivity by increased protein expression of total AKT, IRα and IRS1. We did not find alterations in inflammatory parameters analyzed. EGCG was able to prevent obesity stimulating the mitochondrial complex chain, increasing energy expenditure, particularly from the oxidation of lipid substrates, thereby contributing to the prevention of hepatic steatosis and improved insulin sensitivity.
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Catequina/análogos & derivados , Dieta Alta en Grasa/efectos adversos , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Obesidad/complicaciones , Té/química , Animales , Peso Corporal/efectos de los fármacos , Catequina/farmacología , Citocinas/metabolismo , Suplementos Dietéticos , Enzimas/metabolismo , Prueba de Tolerancia a la Glucosa , Resistencia a la Insulina , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Ratones , Enfermedad del Hígado Graso no Alcohólico/etiología , Obesidad/dietoterapia , Obesidad/metabolismoRESUMEN
Supplementation with epigallocatechin-3-gallate (EGCG), which restores metabolic profiles, has been proposed as an option for preventing and treating obesity. We investigated whether decaffeinated green tea extract rich in EGCG, attenuates high-fat diet (HFD)-induced metabolic alterations in Swiss mice. The mice were maintained on either a control diet (CD) or HFD for 8 weeks and supplemented with either a placebo or EGCG (50mg/kg/day). Body weight, serum lipid profiles, cytokine protein expression, and content in epididymal (EPI) and retroperitoneal (RET) adipose tissues, and adipocyte area were measured. The body weights of HFD + placebo-fed mice were increased compared with those of HFD + EGCG-fed mice (28 and 21%, respectively), whereas the body weights of CD + EGCG-fed mice were decreased 16% compared with those of the CD + placebo group. Serum triglyceride levels were decreased 32% in the CD + EGCG group compared with the CD + placebo group. Compared with the CD + placebo group, increased phosphorylation of AMPK and hormone-sensitive lipase in EPI and RET, respectively, was found in the CD + EGCG group. Increased acetyl-CoA carboxylase phosphorylation was observed in both adipose tissues. In addition, TNF-α and IL-10 levels in EPI and adiponectin levels were higher in the CD + EGCG group than in the CD + placebo group. TNF-α levels were lower in the HFD + EGCG group than in the HFD + placebo group. Furthermore, the CD + EGCG group exhibited a lower adipocyte area than the CD + placebo group. These indicate that the effects of decaffeinated green tea extract on body mass may be related to the crosstalk between lipolytic and inflammatory pathways in normolipidic diet-fed mice but not in HFD-fed mice.
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Camellia sinensis/química , Catequina/análogos & derivados , Suplementos Dietéticos , Manipulación de Alimentos , Hiperlipidemias/prevención & control , Hipolipemiantes/uso terapéutico , Resistencia a la Insulina , Absorción Fisicoquímica , Tejido Adiposo Blanco/inmunología , Tejido Adiposo Blanco/metabolismo , Tejido Adiposo Blanco/patología , Adiposidad , Animales , Fármacos Antiobesidad/análisis , Fármacos Antiobesidad/química , Fármacos Antiobesidad/aislamiento & purificación , Fármacos Antiobesidad/uso terapéutico , Biomarcadores/sangre , Brasil , Catequina/análisis , Catequina/aislamiento & purificación , Catequina/uso terapéutico , Dieta Alta en Grasa/efectos adversos , Suplementos Dietéticos/análisis , Hiperlipidemias/inmunología , Hiperlipidemias/metabolismo , Hiperlipidemias/patología , Hipolipemiantes/análisis , Hipolipemiantes/química , Hipolipemiantes/aislamiento & purificación , Masculino , Ratones , Obesidad/inmunología , Obesidad/metabolismo , Obesidad/patología , Obesidad/prevención & control , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Hojas de la Planta/química , Distribución Aleatoria , Aumento de PesoRESUMEN
The clinical journey of cancer patients is frequently complicated by the development of a complex and multifaceted syndrome, the main features of which are reduced appetite, decreased food intake, progressive weight loss, and wasting of muscle mass and adipose tissue, which is not prevented by the provision of calories and proteins. This syndrome, termed Cachexia, is responsible for increased morbidity, reduced survival, and impinged quality of life of cancer patients. The pathogenesis is complex and involves deranged metabolism of peripheral tissues and profound alterations of brain neurochemistry. Recent studies indicate that brain neurochemistry is perturbed during tumor growth by cancer-induced increased intrahypothalamic expression of proinflammatory cytokines. The attending neurochemical chaos mediates the anorexigenic behavioral responses associated to cancer cachexia, but recent data seem to suggest that neuronal output also may be involved in the metabolic changes occurring at the peripheral level.
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Caquexia/etiología , Hipotálamo/fisiología , Inflamación/complicaciones , Neoplasias/complicaciones , Humanos , Síndrome Debilitante/etiologíaRESUMEN
Dexamethasone (DEXA) is a potent immunosupressant and anti-inflammatory agent whose main side effects are muscle atrophy and insulin resistance in skeletal muscles. In this context, leucine supplementation may represent a way to limit the DEXA side effects. In this study, we have investigated the effects of a low and a high dose of leucine supplementation (via a bolus) on glucose homeostasis, muscle mass and muscle strength in energy-restricted and DEXA-treated rats. Since the leucine response may also be linked to the administration of this amino acid, we performed a second set of experiments with leucine given in bolus (via gavage) versus leucine given via drinking water. Leucine supplementation was found to produce positive effects (e.g., reduced insulin levels) only when administrated in low dosage, both via the bolus or via drinking water. However, under DEXA treatment, leucine administration was found to significantly influence this response, since leucine supplementation via drinking water clearly induced a diabetic state, whereas the same effect was not observed when supplied via the gavage.
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Glucemia/metabolismo , Dexametasona/efectos adversos , Glucocorticoides/efectos adversos , Resistencia a la Insulina , Insulina/sangre , Leucina/administración & dosificación , Músculo Esquelético/efectos de los fármacos , Animales , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Vías de Administración de Medicamentos , Homeostasis/efectos de los fármacos , Leucina/farmacología , Leucina/uso terapéutico , Masculino , Fuerza Muscular/efectos de los fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Atrofia Muscular/inducido químicamente , Atrofia Muscular/tratamiento farmacológico , Ratas , Ratas WistarRESUMEN
Cancer cachexia causes metabolic alterations with a marked effect on hepatic lipid metabolism. L-Carnitine modulates lipid metabolism and its supplementation has been proposed as a therapeutic strategy in many diseases. In the present study, the effects of L-carnitine supplementation on gene expression and on liver lipid metabolism-related proteins was investigated in cachectic tumour-bearing rats. Wistar rats were assigned to receive 1 g/kg of L-carnitine or saline. After 14 days, supplemented and control animals were assigned to a control (N), control supplemented with L-carnitine (CN), tumour-bearing Walker 256 carcinosarcoma (TB) and tumour-bearing supplemented with L-carnitine (CTB) group. The mRNA expression of carnitine palmitoyltransferase I and II (CPT I and II), microsomal triglyceride transfer protein (MTP), liver fatty acid-binding protein (L-FABP), fatty acid translocase (FAT/CD36), peroxisome proliferator-activated receptor-alpha (PPAR-alpha) and organic cation transporter 2 (OCTN2) was assessed, and the maximal activity of CPT I and II in the liver measured, along with plasma and liver triacylglycerol content. The gene expression of MTP, and CPT I catalytic activity were reduced in TB, who also showed increased liver (150%) and plasma (3.3-fold) triacylglycerol content. L-Carnitine supplementation was able to restore these parameters back to control values (p<0.05). These data show that L-carnitine preserves hepatic lipid metabolism in tumour-bearing animals, suggesting its supplementation to be of potential interest in cachexia.
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Caquexia/dietoterapia , Carcinoma 256 de Walker/dietoterapia , Carnitina/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/metabolismo , Animales , Carnitina O-Palmitoiltransferasa/metabolismo , Suplementos Dietéticos , Expresión Génica/efectos de los fármacos , Lípidos/sangre , Hígado/efectos de los fármacos , Hígado/patología , Ratas , Ratas WistarRESUMEN
We examined whether feeding pregnant and lactating rats with hydrogenated vegetable fats rich in trans fatty acids led to an increase in serum endotoxin levels and inflammation and to impaired satiety-sensing pathways in the hypothalamus of 90-day-old offspring. Pregnant and lactating Wistar rats were fed either a standard chow (Control) or one enriched with hydrogenated vegetable fat (Trans). Upon weaning, the male offspring were divided in two groups: Control-Control (CC), mothers and offspring fed the control diet; and Trans-Control (TC), mothers fed the trans diet, and offspring fed the control diet. The offspring's food intake and body weight were quantified weekly and the offspring were killed on the 90th day of life by decapitation. The blood and hypothalamus were collected from the offspring. Food intake and body weight were higher in the TC rats than in the CC rats. TC rats had increased serum endotoxin levels and increased hypothalamic cytokines, IL-6, TNF-α and IL1-ß, concentrations (P<.05). TLR4, NFκBp65 and MyD88 were higher (P<.05) in the TC rats than in the CC rats. AdipoR1 was lower in the TC rats than in the CC rats. Thus, the present study shows that the mothers' hydrogenated vegetable fat intake during pregnancy and lactation led to hypothalamic inflammation and impaired satiety-sensing, which promotes deleterious metabolic consequences such as obesity, even after the withdrawal of the causal factor. In other words, the effect remains after the consumption of the standard chow by offspring.
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Hipotálamo/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/genética , Ácidos Grasos trans/administración & dosificación , Animales , Peso Corporal , Endotoxinas/sangre , Ingestión de Energía , Femenino , Bacterias Gramnegativas/aislamiento & purificación , Humanos , Hipotálamo/metabolismo , Hipotálamo/patología , Interleucina-1beta/sangre , Interleucina-6/sangre , Lactancia/metabolismo , Masculino , Embarazo , Ratas , Ratas Wistar , Receptores de Adiponectina/genética , Receptores de Adiponectina/metabolismo , Receptor Toll-Like 4/metabolismo , Factor de Transcripción ReIA/metabolismo , Factor de Necrosis Tumoral alfa/sangre , DesteteRESUMEN
Anorexia and muscle wasting are frequently observed in cancer patients and influence their clinical outcome. The better understanding of the mechanisms underlying behavioral changes and altered metabolism yielded to the development of specialized nutritional support, which enhances utilization of provided calories and proteins by counteracting some of the metabolic derangements occurring during tumor growth. Inflammation appears to be a key factor determining the cancer-associated biochemical abnormalities eventually leading to anorexia and cachexia. Interestingly, inflammation is also involved in carcinogenesis, cancer progression and metastasis by impairing immune surveillance, among other mechanisms. Therefore, nutritional interventions aiming at modulating inflammation to restore nutritional status may also result in improved response to pharmacological anti-cancer therapies. Recent clinical data show that supplementation with nutrients targeting inflammation and immune system increases response rate and survival in cancer patients. This suggests that nutrition therapy should be considered as an important adjuvant strategy in the multidimensional approach to cancer patients.
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Anorexia/complicaciones , Anorexia/terapia , Caquexia/complicaciones , Caquexia/terapia , Terapias Complementarias/métodos , Suplementos Dietéticos , Neoplasias/complicaciones , Animales , Anorexia/dietoterapia , Encéfalo/patología , Encéfalo/fisiopatología , Caquexia/dietoterapia , HumanosRESUMEN
Cancer cachexia is a multifaceted syndrome characterized, among many symptoms, by extensive muscle wasting. Chronic systemic inflammation, partly triggered and sustained by cytokines, as well as increased oxidative stress contributes to the pathogenesis of this complex metabolic disorder. l-carnitine plays a central role in the metabolism of fatty acids and shows important antioxidant and anti-inflammatory properties. Systemic carnitine depletion has been described in several diseases, and it is characterized by fatigue, muscle weakness, and decreased tolerance to metabolic stress. In cachectic cancer patients, low serum carnitine levels have been reported, and this change has been suggested to play an important contributory role in the development of cachexia. Based on these data, carnitine supplementation has been tested in preliminary studies concerning human cachexia, resulting in improved fatigue and quality of life. We present here a review of clinical and experimental evidence regarding the use of carnitine supplementation in the management of cancer cachexia.
RESUMEN
Amino acids such as leucine and its metabolite α-ketoisocaproate (KIC), are returning to be the focus of studies, mainly because of their anti-catabolic properties, through inhibition of muscle proteolysis and enhancement of protein synthesis. It is clear that these effects may counteract catabolic conditions, as well as enhance skeletal muscle mass and strength in athletes. Moreover, beta-hydroxy-beta-methylbutyrate (HMB) has been shown to produce an important effect in reducing muscle damage induced by mechanical stimuli of skeletal muscle. This review aims to describe the general scientific evidence of KIC and HMB supplementation clinical relevance, as well as their effects (e.g., increases in skeletal muscle mass and/or strength), associated with resistance training or other sports. Moreover, the possible mechanisms of cell signaling regulation leading to increases and/or sparing (during catabolic conditions) of skeletal muscle mass are discussed in detail based on the recent literature.
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Cetoácidos/administración & dosificación , Leucina/administración & dosificación , Fuerza Muscular/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Valeratos/administración & dosificación , Administración Oral , Adulto , Rendimiento Atlético , Composición Corporal , Suplementos Dietéticos , Humanos , Cetoácidos/metabolismo , Leucina/metabolismo , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Entrenamiento de Fuerza , Transducción de Señal/efectos de los fármacos , Valeratos/metabolismoRESUMEN
Conjugated linoleic acid (CLA) is a class of 28 positional and geometric isomers of linoleic acid octadecadienoic.Currently, it has been described many benefits related to the supplementation of CLA in animals and humans, as in the treatment of cancer, oxidative stress, in atherosclerosis, in bone formation and composition in obesity, in diabetes and the immune system. However, our results show that, CLA appears to be not a good supplement in patients with cachexia.
RESUMEN
The anorexia-cachexia syndrome is a debilitating clinical condition characterizing the course of chronic diseases, which heavily impacts on patients' morbidity and quality of life, ultimately accelerating death. The pathogenesis is multifactorial and reflects the complexity and redundancy of the mechanisms controlling energy homeostasis under physiological conditions. Accumulating evidence indicates that, during disease, disturbances of the hypothalamic pathways controlling energy homeostasis occur, leading to profound metabolic changes in peripheral tissues. In particular, the hypothalamic melanocortin system does not respond appropriately to peripheral inputs, and its activity is diverted largely toward the promotion of catabolic stimuli (i.e., reduced energy intake, increased energy expenditure, possibly increased muscle proteolysis, and adipose tissue loss). Hypothalamic proinflammatory cytokines and serotonin, among other factors, are key in triggering hypothalamic resistance. These catabolic effects represent the central response to peripheral challenges (i.e., growing tumor, renal, cardiac failure, disrupted hepatic metabolism) that are likely sensed by the brain through the vagus nerve. Also, disease-induced changes in fatty acid oxidation within hypothalamic neurons may contribute to the dysfunction of the hypothalamic melanocortin system. Ultimately, sympathetic outflow mediates, at least in part, the metabolic changes in peripheral tissues. Other factors are likely involved in the pathogenesis of the anorexia-cachexia syndrome, and their role is currently being elucidated. However, available evidence shows that the constellation of symptoms characterizing this syndrome should be considered, at least in part, as different phenotypes of common neurochemical/metabolic alterations in the presence of a chronic inflammatory state.
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Anorexia/fisiopatología , Caquexia/fisiopatología , Sistema Nervioso/fisiopatología , Animales , Anorexia/metabolismo , Caquexia/metabolismo , Citocinas/fisiología , Humanos , Hipotálamo/metabolismo , Hipotálamo/fisiopatología , Melanocortinas/fisiología , Sistema Nervioso/metabolismo , Serotonina/fisiología , SíndromeRESUMEN
BACKGROUND & AIMS: Cancer cachexia affects intermediary metabolism with intense and general catabolism. Walker 256 tumor is a model injected either subcutaneously (Sc) or intraperitoneally (Ip), with different metabolic features. Beta-hydroxy beta-methylbutyrate (HMbeta) is a leucine metabolite with anti-catabolic properties, the aim of this study being to investigate its effects on metabolic parameters in both tumor models. METHODS: Controls (subcutaneous control group (ScC) and intraperitoneal control group (IpC)) and supplemented animals (subcutaneous supplemented group (ScS) and intraperitoneal supplemented group (IpS)) showed these results. RESULTS: Protein Sc values were (47.8%) lower than Ip groups. Sc group fat content was (65.16%) higher than Ip groups. Liver glycogen value for Sc groups was (38.4%) higher than Ip groups. Muscle glycogen value for Sc groups were (2.75 times) higher than Ip groups. Corticosterone and insulin values were lower (44.53%) and higher (45.94%), respectively, in Sc when compared with Ip groups. Glucose and lactate values for ScS were the lowest (61.7% and 41.53%) compared to other groups. ScC glutamine value was the highest (40.8%) of all groups. Glutamate Sc values were (42.65%) lower than Ip groups. Sc groups showed greater survival time compared with Ip groups. ScS group showed 100% increase in survival time when compared with ScC. CONCLUSIONS: HMbeta supplementation can increase survival time and promotes metabolic changes in cancer-bearing animals, but it seems to work in a time-dependent manner.
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Ácido 3-Hidroxibutírico/administración & dosificación , Composición Corporal/efectos de los fármacos , Carcinoma 256 de Walker/metabolismo , Metabolismo Energético/efectos de los fármacos , Glucógeno/metabolismo , Tejido Adiposo/metabolismo , Animales , Composición Corporal/fisiología , Caquexia/metabolismo , Caquexia/mortalidad , Caquexia/prevención & control , Carcinoma 256 de Walker/mortalidad , Suplementos Dietéticos , Modelos Animales de Enfermedad , Metabolismo Energético/fisiología , Inyecciones Intraperitoneales , Inyecciones Subcutáneas , Glucógeno Hepático/metabolismo , Masculino , Proteínas/metabolismo , Ratas , Ratas Wistar , Tasa de Supervivencia , Factores de TiempoRESUMEN
BACKGROUND AND AIMS: Guarana is widely consumed by athletes, either in supplements or in soft drinks, under the belief that it presents ergogenic and "fat burning" effects. We examined the effect of guarana supplementation (14 days) upon aspects of lipid metabolism in sedentary (C) and trained rats (T). METHODS: To isolate the effect of caffeine from that of other components of guarana, we adopted two different doses of whole extract (G1-0.130 g/kg; G2-0.325 g/kg) or decaffeinated extract (DG1, DG2). Body weight, food and water intake; muscle fat content, oleate incorporation, glycogen content, and carnitine palmitoyltransferase I (CPT I) activity and mRNA expression; along with plasma lactate concentration, were assessed. RESULTS: Muscle oleate incorporation was decreased in rats receiving decaffeinated guarana in relation to G1 and G2; as was CPT I mRNA expression in the gastrocnemius. Whole extract supplementation, but not DG induced reduced plasma lactate concentration in trained rats. G1 showed higher muscle glycogen content compared with all other groups. The results show an effect of guarana on aspects of lipid metabolism, which is abolished by decaffeination. CONCLUSION: The changes in lipid metabolism of supplemented rats herein reported are associated with the methylxanthine content of guarana.
Asunto(s)
Metabolismo de los Lípidos/efectos de los fármacos , Paullinia/química , Condicionamiento Físico Animal/fisiología , Extractos Vegetales/farmacología , Xantinas/farmacología , Animales , Cafeína/farmacología , Suplementos Dietéticos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Glucógeno/metabolismo , Humanos , Masculino , Músculo Esquelético/metabolismo , Ácido Oléico/metabolismo , ARN Mensajero/metabolismo , Distribución Aleatoria , Ratas , Ratas WistarRESUMEN
Os ácidos graxos säo o principal substrato energético utilizado pelas fibras musculares durante a realizaçäo de um exercício de intensidade submáxima e longa duraçäo. A instalaçäo da fadiga periférica durante este tipo de atividade está relacionada à reduçäo dos estoques endógenos de carboidrato. A adoçäo da suplementaçäo lipídica visa maximizar a utilizaçäo deste tipo de substrato em detrimento aos estoques de carboidrato, promovendo assim, o efeito poupador de glicogênio ("sparing effect"). A suplementaçäo lipídica para atividades de "endurance" pode ser classificada em duas principais estratégias: a) elevaçäo aguda dos ácidos graxos no plasma e b) administraçäo de dietas hiperlipídicas. Existe, contudo, muita controvérsia em relaçäo aos possíveis efeitos benéficos ou deletérios deste tipo de suplementaçäo para atletas. O objetivo deste trabalho foi revisar a literatura sobre os efeitos da suplementaçäo lipídica sobre o desempenho físico tento de animais como de humanos