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1.
Nutr Metab Cardiovasc Dis ; 23 Suppl 1: S19-24, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22749678

RESUMO

According to a recent consensus, cachexia is a complex metabolic syndrome associated with underlying illness and characterised by loss of muscle with or without loss of fat mass. The prominent clinical feature of cachexia is weight loss. Cachexia occurs in the majority of terminal cancer patients and it is responsible for the deaths of 22% of cancer patients. Although body weight is, indeed, an important factor to be taken into consideration in any cachexia treatment, body composition, physical performance and quality of life should be monitored. From the results presented here, one can speculate that a single therapy may not be completely successful in the treatment of cachexia. From this point of view, treatments involving different combinations are more likely to be successful. The objectives of any therapeutical combination are two: an anticatabolic aim directed towards both fat and muscle catabolism and an anabolic objective leading to the synthesis of macromolecules such as contractile proteins.


Assuntos
Caquexia/dietoterapia , Caquexia/tratamento farmacológico , Suplementos Nutricionais , Neoplasias/complicações , Animais , Anorexia/dietoterapia , Anorexia/tratamento farmacológico , Anorexia/metabolismo , Peso Corporal , Caquexia/metabolismo , Humanos
2.
Endocr Rev ; 13(3): 515-24, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1425486

RESUMO

Cytokines, in particular IL-1, released mainly by infiltrating macrophages, can be one of the key mediators of immune-induced beta-cell destruction in IDDM. IL-1 is able to induce suppression of insulin release and biosynthesis in cultured rat pancreatic islets. In addition, the cytokine shows clear cytotoxic effects leading to beta-cell death. The proposed mechanisms of action of IL-1 after binding to the beta-cell receptors are varied. Concerning the cytotoxic effects of the cytokine, the role of oxygen free radicals, mainly derived from arachidonate metabolism (see Fig. 1) is clear, and possibly potentiated by a cytosolic Na(+)-mediated alkalinization of the beta-cell exposed to the cytokine. In fact, an increased influx of Na+ may explain some of the cytotoxicity since it results in concomitant water uptake leading to swelling of the endoplasmic reticulum. NO formation also seems to be related to the cytokine-induced cytotoxicity since inhibition of the NO synthase abolishes the effects of the cytokine (see Fig. 1). In relation to the inhibitory effects of the cytokine on the beta-cell, different studies point toward almost all known second messenger systems already described for several hormones, such as cAMP formation, increased phospholipase C activity, changes in cytosolic Ca++, and altered gene transcription (see Fig. 1). Of particular interest is the protease activation associated with IL-1 (a serine protease) that seems to be clearly connected with the effects of the cytokine upon the beta-cell. In conclusion, the different studies devoted to the problem of IL-1 signal transduction on the beta-cell seem to indicate that the action of the cytokine on the pancreatic insulin-secreting cells is not associated with an individual second messenger system but rather seems to be related to a plurifactorial transduction system.


Assuntos
Interleucina-1/fisiologia , Ilhotas Pancreáticas/fisiologia , Sistemas do Segundo Mensageiro/fisiologia , Animais , Doenças Autoimunes/fisiopatologia , Citocinas/fisiologia , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/fisiopatologia , Humanos , Insulina/metabolismo , Secreção de Insulina
3.
J Clin Invest ; 92(6): 2783-9, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8254032

RESUMO

Rats bearing the Yoshida AH-130 ascites hepatoma showed enhanced fractional rates of protein degradation in gastrocnemius muscle, heart, and liver, while fractional synthesis rates were similar to those in non-tumor bearing rats. This hypercatabolic pattern was associated with marked perturbations of the hormonal homeostasis and presence of tumor necrosis factor in the circulation. The daily administration of a goat anti-murine TNF IgG to tumor-bearing rats decreased protein degradation rates in skeletal muscle, heart, and liver as compared with tumor-bearing rats receiving a nonimmune goat IgG. The anti-TNF treatment was also effective in attenuating early perturbations in insulin and corticosterone homeostasis. Although these results suggest that tumor necrosis factor plays a significant role in mediating the changes in protein turnover and hormone levels elicited by tumor growth, the inability of such treatment to prevent a reduction in body weight implies that other mediators or tumor-related events were also involved.


Assuntos
Caquexia/metabolismo , Imunoglobulina G/farmacologia , Neoplasias Hepáticas Experimentais/fisiopatologia , Neoplasias Hepáticas/fisiopatologia , Proteínas/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Animais , Rim/metabolismo , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Músculos/metabolismo , Miocárdio/metabolismo , Especificidade de Órgãos , Ratos , Ratos Wistar , Valores de Referência , Fator de Necrose Tumoral alfa/imunologia
4.
J Clin Invest ; 95(5): 2367-72, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7738199

RESUMO

Tissue protein hypercatabolism (TPH) is a most important feature in cancer cachexia, particularly with regard to the skeletal muscle. The rat ascites hepatoma Yoshida AH-130 is a very suitable model system for studying the mechanisms involved in the processes that lead to tissue depletion, since it induces in the host a rapid and progressive muscle waste mainly due to TPH (Tessitore, L., G. Bonelli, and F. M. Baccino. 1987. Biochem. J. 241:153-159). Detectable plasma levels of tumor necrosis factor-alpha associated with marked perturbations in the hormonal homeostasis have been shown to concur in forcing metabolism into a catabolic setting (Tessitore, L., P. Costelli, and F. M. Baccino. 1993. Br. J. Cancer. 67:15-23). The present study was directed to investigate if beta 2-adrenergic agonists, which are known to favor skeletal muscle hypertrophy, could effectively antagonize the enhanced muscle protein breakdown in this cancer cachexia model. One such agent, i.e., clenbuterol, indeed largely prevented skeletal muscle waste in AH-130-bearing rats by restoring protein degradative rates close to control values. This normalization of protein breakdown rates was achieved through a decrease of the hyperactivation of the ATP-ubiquitin-dependent proteolytic pathway, as previously demonstrated in our laboratory (Llovera, M., C. García-Martínez, N. Agell, M. Marzábal, F. J. López-Soriano, and J. M. Argilés. 1994. FEBS (Fed. Eur. Biochem. Soc.) Lett. 338:311-318). By contrast, the drug did not exert any measurable effect on various parenchymal organs, nor did it modify the plasma level of corticosterone and insulin, which were increased and decreased, respectively, in the tumor hosts. The present data give new insights into the mechanisms by which clenbuterol exerts its preventive effect on muscle protein waste and seem to warrant the implementation of experimental protocols involving the use of clenbuterol or alike drugs in the treatment of pathological states involving TPH, particularly in skeletal muscle and heart, such as in the present model of cancer cachexia.


Assuntos
Trifosfato de Adenosina/metabolismo , Clembuterol/farmacologia , Neoplasias Hepáticas Experimentais/fisiopatologia , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Doenças Musculares/prevenção & controle , Receptores Adrenérgicos beta 2/fisiologia , Ubiquitinas/metabolismo , Análise de Variância , Animais , Ascite , Corticosterona/sangue , Hipertrofia , Insulina/sangue , Masculino , Músculo Esquelético/patologia , Doenças Musculares/etiologia , Doenças Musculares/metabolismo , Ratos , Ratos Wistar
5.
Cytokine Growth Factor Rev ; 8(3): 181-8, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9462484

RESUMO

Although tumour necrosis factor-alpha (TNF) was originally described as a cytotoxic molecule produced by macrophages when activated by certain stimuli (such as bacterial endotoxin or tumour cells), a large body of evidence suggests that TNF plays a role in pregnancy. Both in humans and experimental animals, TNF is expressed and synthesized in the endometrium, placenta and fetus. Here we review evidence in support of positive roles for the cytokine in gestation (such as early pregnancy maintenance, and the contribution of TNF to the maintenance of a complex cytokine-hormone network or to parturition). We also present evidence supporting the idea that TNF acts as a negative regulator of pregnancy, or does not play any significant role in gestation at all.


Assuntos
Gravidez/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Feminino , Humanos
6.
Rev Esp Anestesiol Reanim ; 54(10): 608-11, 2007 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-18200996

RESUMO

OBJECTIVE: To evaluate improvement after implementation of care through a nurse-managed acute pain unit in a district hospital, using statistical process control (SPC) methods. MATERIAL AND METHODS: Each month we measured 3 acute pain unit quality indicators: pain prevalence, pain relief, and satisfaction with pain management. The indicators were monitored on P-charts according to SPC procedures that determine their distribution within control limits and track variability. RESULTS: The hospital prevalence of acute pain stabilized at 30% after a year. Eight-five percent of patients achieved adequate pain relief and 90% were satisfied with pain management. CONCLUSIONS: A nurse-managed acute pain unit designed and managed with tools for monitoring quality assurance produces significant absolute and relative improvements in the prevalence of pain, pain relief, and patient satisfaction (P < .001), leading to a savings of 15 000 days of unnecessary suffering per year.


Assuntos
Auditoria Médica , Clínicas de Dor/estatística & dados numéricos , Dor/prevenção & controle , Adulto , Feminino , Hospitais Urbanos/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Dor/epidemiologia , Dor/enfermagem , Manejo da Dor , Medição da Dor , Satisfação do Paciente , Prevalência , Avaliação de Programas e Projetos de Saúde/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de Saúde , Espanha
7.
J Natl Cancer Inst ; 85(16): 1334-9, 1993 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-8340946

RESUMO

BACKGROUND: Many cancer patients experience a wasting syndrome (cachexia) characterized by weight loss and abnormalities in carbohydrate, protein, and lipid metabolism. Recent experimental studies suggest that the development of cancer cachexia involves the host's production of inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha). PURPOSE: Our goal was to evaluate in rats the effects of an 8-day TNF-alpha treatment on overall protein metabolism in the liver, diaphragm, heart, and hind-leg muscles. METHODS: Four experimental groups corresponding to specific tissues (liver, diaphragm, heart, and hind-leg muscles) in female Wistar rats (100-150 g) were studied. Each group consisted of 25 TNF-alpha-treated and 25 control female Wistar rats. The TNF-alpha-treated rats were given intraperitoneal injections of recombinant-derived human TNF-alpha (0.5 mL) that was administered in two daily injections of 50 micrograms/kg (total dose of 100 micrograms/kg per day) for 8 days. Control animals followed the same injection schedule as the treatment group and received 0.5 mL of physiological saline instead of TNF-alpha. All rats were radioactively labeled with NaH14CO3 24 hours prior to TNF-alpha treatment. At 0, 1, 2, 4, and 8 days during TNF-alpha treatment, five rats per group were killed to measure the radioactive decay of labeled protein in specific tissues in order to estimate fractional protein turnover. During necropsy, the liver, hind-leg muscles (soleus muscle analyzed separately on 8th day only), heart, and diaphragm were rapidly weighed, and each was homogenized. Total protein content and total DNA were also determined. Total protein radioactivity and specific protein radioactivity (per milligram of protein) were evaluated for liver, diaphragm, heart, and hind-leg muscles. Radioactivity was counted in a liquid scintillation counter. Fractional rates of protein synthesis, protein degradation, total protein, and protein accumulation or loss were calculated. RESULTS: The TNF-alpha treatment administered to female Wistar rats for 8 days resulted in a transient decrease in food intake and body weight 24 hours after the beginning of the TNF-alpha treatment. In all types of tissues studied, TNF-alpha treatment resulted in increases in both the protein synthesis and protein degradation, with a greater increase in the protein degradation that resulted in a reduced protein accumulation following TNF-alpha treatment. This reduction in protein accumulation was directly associated with a decreased soleus muscle mass on day 8 of the treatment. CONCLUSIONS: Data suggest that TNF-alpha enhances muscle degradation in experimental situations where body weight loss is not apparent.


Assuntos
Proteínas Musculares/metabolismo , Músculos/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Animais , Peso Corporal/fisiologia , Caquexia/metabolismo , Diafragma/metabolismo , Ingestão de Alimentos/fisiologia , Feminino , Membro Posterior , Fígado/metabolismo , Miocárdio/metabolismo , Proteínas/metabolismo , Ratos , Ratos Wistar , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/administração & dosagem
8.
Nutr Hosp ; 21 Suppl 3: 4-9, 2006 May.
Artigo em Espanhol | MEDLINE | ID: mdl-16768025

RESUMO

The regulation of food intake is mediated by different psicological, gastrointestinal metabolic, nutritional and endocrine mechanisms. The cancer patient suffers from anorexia which results in early saciety and a reduction of appetite. Sometimes, the causes of the anorectic response are derived from the antitumoral treatment (chemotherapy, radiotherapy or immunotherapy), in some cases vomiting resulting in altered food intake. Alterations in the food taste and smell perception in addition to psychological dearrangements might also lead to the anorexia. Sometimes the tumour may play a direct effect when it is localised in either the hypothalamus or the digestive apparatus. However, in the majority of cases the origin of the anorexia associated with cancer cachexia seems to be due to the metabolic alterations induced by tumour burden. Different factors of both humoral and tumoral origin play a role in cancer anorexia. For instance, tumour necrosis factor (TNF-), a cytokine responsible for a great part of the metabolic alterations characteristic of cancer cachexia seems to be involved. In conclusion, the cancer anorexia seems to be more an effect than the cause of the weight loss and in fact the decrease in food intake might take place after weight loss is evident. In any case, the malnutrition associated with a decrease of food intake worsens the cachectic state, favouring a kind of a positive feed-back mechanism that finally leads to the patient's death.


Assuntos
Caquexia/etiologia , Caquexia/fisiopatologia , Neoplasias/complicações , Caquexia/imunologia , Caquexia/metabolismo , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo
9.
Adv Gerontol ; 18: 39-54, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16676797

RESUMO

Muscle wasting during cancer and ageing share many common metabolic pathways and mediators. Due to the size of the population involved, both cancer cachexia and ageing sarcopenia may represent targets for future promising clinical investigations. Cancer cachexia is a syndrome characterized by a marked weight loss, anorexia, asthenia and anemia. In fact, many patients who die with advanced cancer suffer from cachexia. The degree of cachexia is inversely correlated with the survival time of the patient and it always implies a poor prognosis. In recent years, age-related diseases and disabilities have become of major health interest and importance. This holds particularly for muscle wasting, also known as sarcopenia that decreases the quality of life of the geriatric population, increasing morbidity and decreasing life expectancy. The cachectic factors (associated with both depletion of fat stores and muscular tissue) can be divided into two categories: of tumour origin and humoural factors. In conclusion, more research should be devoted to the understanding of muscle wasting mediators, both in cancer and ageing, in particular the identification of common mediators may prove as a good therapeutic strategy for both prevention and treatment of wasting both in disease and during healthy ageing.


Assuntos
Envelhecimento , Caquexia/etiologia , Atrofia Muscular/etiologia , Neoplasias , Caquexia/metabolismo , Humanos , Atrofia Muscular/metabolismo , Neoplasias/complicações , Neoplasias/imunologia , Neoplasias/metabolismo
10.
Cancer Res ; 47(21): 5644-6, 1987 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-3664471

RESUMO

Blood amino acid compartmentation between plasma and red blood cells was studied in mice bearing the Lewis lung carcinoma. The animals showed a change in compartmentation with an increase in the concentration of most amino acids in the plasmatic fraction with the exception of glycine, glutamine, aspartate, asparagine, and taurine. This work focuses on the importance of studying the distribution of amino acids in both fractions when performing studies concerning amino acid metabolism in tumor-bearing animals.


Assuntos
Aminoácidos/sangue , Neoplasias Experimentais/sangue , Animais , Eritrócitos/análise , Neoplasias Pulmonares/sangue , Camundongos , Camundongos Endogâmicos C57BL , Taurina/sangue
11.
Rev Esp Anestesiol Reanim ; 53(2): 110-3, 2006 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-16553344

RESUMO

Cerebellar hemorrhage is a rare complication of spinal anesthesia. We report a case in a 51-year-old woman with a history of hypertension who underwent uterine dilatation and curettage with spinal anesthesia. During recovery she vomited and complained of headache. Postdural puncture headache was diagnosed. When there was no response to conventional treatment, computed tomography and magnetic resonance scans of the head were performed. The scans confirmed cerebellar hemorrhage due to rupture of a cavernous angioma. The patient recovered fully without surgical decompression. We review the pathogenesis of headache and cerebral hemorrhage after spinal anesthesia and propose differential diagnosis between spontaneous rupture related to hypertension and cerebrospinal fluid hypotension syndrome caused by trauma from lumbar spinal puncture. Patients with prolonged severe headache after spinal anesthesia require neurologic and radiologic monitoring to rule out the possibility of intracranial complications.


Assuntos
Raquianestesia/efeitos adversos , Hemorragias Intracranianas/etiologia , Cerebelo , Feminino , Humanos , Pessoa de Meia-Idade , Cefaleia Pós-Punção Dural/etiologia
12.
Rev Calid Asist ; 31(1): 55-63, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-26420516

RESUMO

OBJECTIVE: Although several clinical practice guidelines have been developed in the last decades, cancer pain management is still deficient. The purpose of this work was to carry out a comprehensive and systematic literature review of current clinical practice guidelines on cancer pain management, and critically appraise their methodology and content in order to evaluate their quality and validity to cope with this public health issue. MATERIALS AND METHODS: A systematic review was performed in the main databases, using English, French and Spanish as languages, from 2008 to 2013. Reporting and methodological quality was rated with the Appraisal of Guidelines, Research and Evaluation II (AGREE-II) tool, including an inter-rater reliability analysis. Guideline recommendations were extracted and classified into several categories and levels of evidence, aiming to analyse guidelines variability and evidence-based content comprehensiveness. RESULTS: Six guidelines were included. A wide variability was found in both reporting and methodological quality of guidelines, as well as in the content and the level of evidence of their recommendations. The Scottish Intercollegiate Guidelines Network guideline was the best rated using AGREE-II, while the Sociedad Española de Oncología Médica guideline was the worst rated. The Ministry of Health Malaysia guideline was the most comprehensive, and the Scottish Intercollegiate Guidelines Network guideline was the second one. CONCLUSIONS: The current guidelines on cancer pain management have limited quality and content. We recommend Ministry of Health Malaysia and Scottish Intercollegiate Guidelines Network guidelines, whilst Sociedad Española de Oncología Médica guideline still needs to improve.


Assuntos
Dor do Câncer/terapia , Manejo da Dor , Medicina Baseada em Evidências , Humanos , Neoplasias , Guias de Prática Clínica como Assunto , Reprodutibilidade dos Testes
13.
Biochim Biophys Acta ; 925(3): 265-71, 1987 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-2887209

RESUMO

The amino acid pool composition and its concentration ratios with respect to blood and plasma, as well as the activities of alanine, aspartate and branched chain amino acid transaminases, glutamine synthetase, adenylate deaminase and glutamate dehydrogenase have been studied in the interscapular brown adipose tissue of control, 12-h cold-exposed and 15-day cold-acclimated rats. Cold temperature affected the amino acid metabolism and pool composition more intensely after 15 days than after 12-h cold-exposure, even though the patterns of change were very similar in both groups. Cold temperatures induced a decrease in glutamine and an increase in glutamate concentration in the tissue. This probably increased the metabolism of branched chain amino acids and caused a decrease in adenylate deaminase activity. It also seemed to increase alanine utilization. We concluded that amino acid metabolism in brown adipose tissue is enhanced by cold temperature acclimation.


Assuntos
Aclimatação , Tecido Adiposo Marrom/metabolismo , Aminoácidos/metabolismo , Temperatura Baixa , AMP Desaminase/metabolismo , Tecido Adiposo Marrom/enzimologia , Animais , Glutamato Desidrogenase/metabolismo , Glutamato-Amônia Ligase/metabolismo , Masculino , Ratos , Ratos Endogâmicos , Transaminases/metabolismo
14.
Biochim Biophys Acta ; 1010(3): 338-41, 1989 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-2920181

RESUMO

The rates of either glucose or alanine incorporation into tissue and oxidation to CO2 were studied in rat interscapular brown adipose tissue in order to evaluate the mutual influence of both substrates on their uptake and utilization. Tissue fragments were incubated in vitro in the presence of 1-10 mM glucose and 0.3-1.5 mM alanine. The highest glucose oxidation rate was obtained with the lowest alanine concentrations tested. This suggests that alanine inhibits glucose utilization by this tissue at concentrations that are within the physiological plasmatic range. Glucose levels had little effect upon alanine oxidation, but glucose had a permissive effect on the utilization of alanine. On the basis of these results, it is postulated that this glucose conservation effect of alanine on brown adipose tissue can help to prevent glucose wastage in postprandrial situations.


Assuntos
Tecido Adiposo Marrom/metabolismo , Alanina/farmacologia , Glucose/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Alanina/metabolismo , Animais , Glucose/farmacologia , Técnicas In Vitro , Masculino , Oxirredução , Ratos , Ratos Endogâmicos
15.
Biochim Biophys Acta ; 1036(1): 6-10, 1990 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-2121275

RESUMO

The in vitro oxidation to CO2 and tissue incorporation of alanine label by pieces of rat interscapular brown adipose tissue (IBAT) has been investigated. Insulin increased both uptake and oxidation of alanine, as well as the incorporation of alanine label into tissue. This effect only was observed in the presence of glucose in the incubation medium. Noradrenaline hampered alanine incorporation, not affecting its rate of oxidation. IBAT from 4-h cold-exposed rats showed a higher alanine utilization than that of controls; however, IBAT pieces from both 36-h starved and 30-day cold-exposed rats presented lower rates of alanine utilization. The main fate of alanine taken up by the IBAT pieces was its oxidation to CO2. Part of the label was also incorporated into the fatty acid fraction of lipids. The results obtained in this study agree with a possible role of alanine as alternative energetic substrate for IBAT.


Assuntos
Tecido Adiposo Marrom/metabolismo , Alanina/metabolismo , Animais , Dióxido de Carbono/metabolismo , Técnicas In Vitro , Insulina/farmacologia , Masculino , Norepinefrina/farmacologia , Ratos , Ratos Endogâmicos
16.
Biochim Biophys Acta ; 1475(1): 5-9, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10806331

RESUMO

The Yoshida AH-130 rat ascites hepatoma is a model system for studying the mechanisms involved in the protein hypercatabolism associated with cancer cachexia. The present study was aimed at investigating if the calpain-3 gene expression in skeletal muscle was affected by tumor growth. The results presented clearly show that calpain-3 gene expression is considerably reduced in experimental cancer cachexia, while there is a reciprocal change in the expression of the ubiquitin-dependent proteolytic system and in the ubiquitous m-calpain. The results, observed during cancer cachexia, suggest a potential counterregulatory role of calpain-3 in muscle proteolysis.


Assuntos
Caquexia/enzimologia , Calpaína/genética , Proteínas Musculares/genética , Músculo Esquelético/enzimologia , Animais , Caquexia/etiologia , Calpaína/metabolismo , Sondas de DNA , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Masculino , Proteínas Musculares/metabolismo , Neoplasias Experimentais/complicações , RNA/isolamento & purificação , Ratos , Ratos Wistar
17.
Biochim Biophys Acta ; 1499(3): 249-56, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11341972

RESUMO

In order to understand the role of brain localized uncoupling proteins, we have examined the UCP2 and BMCP-1 gene expression in mice brain in two different catabolic states: administration of lipopolysaccharide (LPS) (2.5 mg/kg, i.p.) and tumour burden. Administration of LPS resulted in an increased UCP2 gene expression both in brain (208%) and cerebellum (77%). An increase in UCP2 gene expression was also observed after LPS treatment in double knockout mice for tumour necrosis factor-alpha (TNF) receptors 1 and 2 (75% in brain and 33% in cerebellum). Tumour growth also resulted in increased brain UCP2 gene expression (80%) in mice bearing the Lewis lung carcinoma as compared with the non-tumour-bearing controls. No changes were observed in BMCP-1 mRNA levels of either LPS-injected or tumour-bearing mice. From the results presented it may be suggested that: (a) the brain may contribute significantly to the increase in energy expenditure associated with hypermetabolic states such as fever and tumour burden, and (b) the regulation of UCP2 gene expression in brain does not seem to be influenced by TNF; therefore the action of other cytokines cannot be discarded.


Assuntos
Encéfalo/metabolismo , Proteínas de Membrana Transportadoras , Proteínas Mitocondriais , Proteínas/genética , Fator de Necrose Tumoral alfa/metabolismo , Animais , Antígenos CD/genética , Proteínas de Transporte/genética , Metabolismo Energético , Feminino , Expressão Gênica/efeitos dos fármacos , Canais Iônicos , Lipopolissacarídeos/toxicidade , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Desacoplamento Mitocondrial , Proteínas do Tecido Nervoso/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Proteína Desacopladora 2
18.
Biochim Biophys Acta ; 1526(1): 17-24, 2001 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-11287118

RESUMO

Interleukin (IL)-15 is a cytokine which is highly expressed in skeletal muscle. Cell culture studies have indicated that IL-15 may have an important role in muscle fiber growth and anabolism. However, data concerning the metabolic effects of this cytokine in vivo are lacking. In the present study, IL-15 was administered to adult rats for 7 days. While IL-15 did not cause changes in either muscle mass or muscle protein content, it induced significant changes in the fractional rates of both muscle protein synthesis and degradation, with no net changes in protein accumulation. Additionally, IL-15 administration resulted in a 33% decrease in white adipose tissue mass and a 20% decrease in circulating triacylglycerols; this was associated with a 47% lower hepatic lipogenic rate and a 36% lower plasma VLDL triacylglycerol content. The decrease in white fat induced by IL-15 was in adipose tissue. No changes were observed in the rate of lipolysis as a result of cytokine administration. These findings indicate that IL-15 has significant effects on both protein and lipid metabolism, and suggest that this cytokine may participate in reciprocal regulation of muscle and adipose tissue mass.


Assuntos
Tecido Adiposo/anatomia & histologia , Peso Corporal/efeitos dos fármacos , Interleucina-15/farmacologia , Músculo Esquelético/anatomia & histologia , Animais , Peso Corporal/fisiologia , Ingestão de Alimentos , Interleucina-15/fisiologia , Lipólise/efeitos dos fármacos , Lipoproteínas VLDL/sangue , Masculino , Proteínas Musculares/biossíntese , Proteínas Musculares/metabolismo , Tamanho do Órgão , Ratos , Ratos Wistar , Triglicerídeos/sangue
19.
Cell Death Differ ; 10(9): 997-1004, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12934074

RESUMO

The liver is particularly susceptible to Fas-mediated cytotoxicity. Mice given an adequate parenteral dose of agonistic anti-Fas antibody (aFas) or of FasL are known to develop a devastating liver injury and to die in a few hours. The present work shows that mice lacking TNFR1 and TNFR2 (R(-)) both survive a single dose of aFas, otherwise rapidly lethal, and develop a mild form of hepatic damage, compared to the much more severe liver injury that in a few hours strikes wild-type mice (R(+)), eventually involving increased activity of proteases of different families (caspase 3-, 8-, and 9-like, calpains, cathepsin B). Neither the overall tissue levels of Fas and FasL nor Fas expression at the hepatocyte surface are altered in the liver of R(-) animals. The DNA-binding activity of the NF-kappaB transcription factor is enhanced after aFas treatment, but much more markedly in R(-) than in R(+) mice. Bcl2, while unchanged in untreated animals, is markedly upregulated in R(-) but not in R(+) mice challenged with aFas. The requirement of a normal TNFR1/TNFR2 phenotype for full deployment of the general and liver-specific aFas toxicity in mice most likely implies that treatment with aFas in some way results in activation of the TNFalpha-TNFRs system and that this activation synergizes with Fas-mediated signals in causing the fulminant liver injury and the animal death. The precise cellular and molecular details underlying this interplay between Fas- and TNFRs-mediated signaling systems in the general and liver-specific aFas toxicity largely remain to be clarified.


Assuntos
Antígenos CD/fisiologia , Apoptose , Hepatite Animal/etiologia , Receptores do Fator de Necrose Tumoral/fisiologia , Receptor fas/metabolismo , Animais , Anticorpos/toxicidade , Antígenos CD/genética , Proteína Ligante Fas , Hepatite Animal/metabolismo , Hepatite Animal/patologia , Fígado/patologia , Fígado/ultraestrutura , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Fator de Necrose Tumoral alfa/fisiologia , Receptor fas/imunologia
20.
Trends Pharmacol Sci ; 17(6): 223-6, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8763200

RESUMO

It is generally accepted that muscle wasting is caused by an increase in protein breakdown which seems to be associated with an ATP-dependent, non-lysosomal proteolytic system based on conjugation of proteins to the small polypeptide ubiquitin. Increases in ubiquitin conjugates and in ubiquitin mRNAs are found in the skeletal muscle of experimental animals with various pathological conditions such as infection, acidosis or cancer cachexia. In this review, Josep Argilés and Francisco López-Soriano discuss the role of the ubiquitin-dependent proteolytic pathway in muscle weight loss in pathological situations.


Assuntos
Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Doenças Musculares/metabolismo , Ubiquitinas/metabolismo , Humanos
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