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1.
Eat Weight Disord ; 25(1): 107-116, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29949130

RESUMO

PURPOSE: This work analyses the meal supply in primary schools in Italy to highlight new areas of inefficiency upstream of the food chain, regarding the size of the food portions specified in public tenders. A lack of conformity of food portions can potentially lead to a double negative externality affecting the sustainability of school meals: overweight children and food waste. METHOD: Based on the data contained in the contract between municipalities and school catering services, the analysis was performed on the portion sizes (in grams) of the main food products included in the school menu for each regional capital (RC) in Italy. Data analysis regarded two main aspects: consistency of food portions within regions and adherence to national standards for childrens. RESULTS: The results revealed great discrepancies amongst regions and in several cases, portion sizes significantly larger than the reference values of standard portions for school catering. The study also profiles RC on the basis of portion sizes, school meal attendance, and childhood obesity rates. CONCLUSIONS: School meals have the potential to educate the next generation regarding healthy eating habits, and thus play a leading role in obesity prevention in children. Similarly, the educational role of eating at school can contribute to raising children's awareness about one of the most urgent environmental challenges-food waste-by introducing the best strategies for waste reduction, reuse, and recycling. Results have economic, social, health, and environmental implications and highlight the need to revisit policies to introduce new solutions for more sustainable and healthy school canteens in Italy. LEVEL OF EVIDENCE: Level V, descriptive studies.


Assuntos
Refeições , Obesidade Infantil/prevenção & controle , Tamanho da Porção , Instituições Acadêmicas , Criança , Comportamento Alimentar , Feminino , Humanos , Itália , Masculino
2.
Eat Weight Disord ; 12(2): 91-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17615493

RESUMO

OBJECTIVE: Food is considered a reinforcing agent, like a variety of substances such as alcohol and other drugs of abuse that produce pleasure. Psychopathological traits related to food intake are demonstrated in eating disorders as in obesity with different genetic aspects for these diseases. Recently, the prevalence of TaqA1 allele has been associated to alcohol, drug abuse and carbohydrate preference. For this reason, the aim of this study was to evaluate if the presence of A1 allele, in eating disorders and obesity, is associated with some particular psycho-pathological characteristics. METHODS: We studied the presence of TaqA1 in Italian subjects affected by obesity (n=71), anorexia (n=28), bulimia (n=20) and in control group (n=54). The Eating Disorders Inventory (EDI test) was used to evaluate the psychological profiles. Patients without alcohol and drugs abuse were selected (>125 ml/day). RESULTS: The A1+ allele, both in A1/A1 and A1/A2 genotypes, was not differently distributed among disease groups; on the contrary two EDI subscales (Drive for thinness and Ineffectiveness) resulted associated with A1+ allele without effect of the eating disease or obesity. CONCLUSION: These results confirm that the presence of A1+ allele is not simply related to body weight but the A1+ allele might be a marker of a genetic psychological condition in people with high risk to develop pathological eating behaviour.


Assuntos
Anorexia Nervosa/genética , Bulimia/genética , Obesidade/genética , Polimorfismo Genético , Receptores de Dopamina D2/genética , Adulto , Anorexia Nervosa/psicologia , Imagem Corporal , Índice de Massa Corporal , Peso Corporal/genética , Bulimia/psicologia , Estudos de Casos e Controles , Feminino , Marcadores Genéticos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/psicologia , Testes Psicológicos , Autoimagem
4.
Eat Weight Disord ; 7(3): 161-7, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12452247

RESUMO

Obesity has now been identified as a chronic disease, a global epidemic (globesity) and a serious public health issue that leads to reduced life expectancy, an increased risk for many serious medical conditions and enormous healthcare costs. The prevalence of obesity and overweight in Italy in 2000 was respectively 9% and 33%, and has grown by 25% over the last five years. Even moderate weight loss can improve obesity-related morbidity and mortality. In November 1997, the US Food and Drug Administration approved sibutramine, a serotonin and noradrenaline reuptake inhibitor, for the treatment of pathological obesity and the management and maintenance of weight loss. In March 2002, sibutramine was temporarily withdrawn from the Italian market on the basis of 47 adverse event reports received between April and December 2001. However, a worldwide review of efficacy and safety data has shown that the overall risk/benefit profile of sibutramine remains favourable, with the rate of fatal reports involving patients receiving sibutramine being 200 times less than the obese women's mortality rate in the Nurses' Health Study. There is strong evidence supporting the usefulness of the correct use of sibutramine in the management of obesity.


Assuntos
Antidepressivos/uso terapêutico , Depressores do Apetite/uso terapêutico , Ciclobutanos/uso terapêutico , Obesidade/tratamento farmacológico , Ciclobutanos/efeitos adversos , Feminino , Humanos , Itália/epidemiologia , Obesidade/mortalidade , Qualidade de Vida , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Redução de Peso/efeitos dos fármacos
5.
Int J Obes Relat Metab Disord ; 26(6): 838-47, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12037655

RESUMO

OBJECTIVE: It has been reported that an increased availability of free fatty acids (NEFA) not only interferes with glucose utilization in insulin-dependent tissues, but may also result in an uncoupling effect of heart metabolism. We aimed therefore to investigate the effect of an increased availability of NEFA on gene expression of proteins involved in transmembrane fatty acid (FAT/CD36) and glucose (GLUT4) transport and of the uncoupling proteins UCP2 and 3 at the heart and skeletal muscle level. STUDY DESIGN: Euglycemic hyperinsulinemic clamp was performed after 24 h Intralipid(R) plus heparin or saline infusion in lean Zucker rats. Skeletal and heart muscle glucose utilization was calculated by 2-deoxy-[1-(3)H]-D-glucose technique. Quantification of FAT/CD36, GLUT4, UCP2 and UCP3 mRNAs was obtained by Northern blot analysis or RT-PCR. RESULTS: In Intralipid(R) plus heparin infused animals a significant decrease in insulin-mediated glucose uptake was observed both in the heart (22.62+/-2.04 vs 10.37+/-2.33 ng/mg/min; P<0.01) and in soleus muscle (13.46+/-1.53 vs 6.84+/-2.58 ng/mg/min; P<0.05). FAT/CD36 mRNA was significantly increased in skeletal muscle tissue (+117.4+/-16.3%, P<0.05), while no differences were found at the heart level in respect to saline infused rats. A clear decrease of GLUT4 mRNA was observed in both tissues. The 24 h infusion of fat emulsion resulted in a clear enhancement of UCP2 and UCP3 mRNA levels in the heart (99.5+/-15.3 and 80+/-4%) and in the skeletal muscle (291.5+/-24.7 and 146.9+/-12.7%). CONCLUSIONS: As a result of the increased availability of NEFA, FAT/CD36 gene expression increases in skeletal muscle, but not at the heart level. The augmented lipid fuel supply is responsible for the depression of insulin-mediated glucose transport and for the increase of UCP2 and 3 gene expression in both skeletal and heart muscle.


Assuntos
Proteínas de Transporte/genética , Emulsões Gordurosas Intravenosas/administração & dosagem , Glicoproteínas de Membrana/genética , Proteínas de Membrana Transportadoras , Proteínas Mitocondriais , Proteínas de Transporte de Monossacarídeos/genética , Proteínas Musculares , Músculos/metabolismo , Transportadores de Ânions Orgânicos/genética , Proteínas/genética , Animais , Glicemia/metabolismo , Northern Blotting , Antígenos CD36 , Ácidos Graxos não Esterificados/sangue , Expressão Gênica , Glucose/metabolismo , Técnica Clamp de Glucose , Transportador de Glucose Tipo 4 , Heparina/administração & dosagem , Insulina/sangue , Insulina/farmacologia , Canais Iônicos , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculos/efeitos dos fármacos , Miocárdio/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/genética , Ratos , Ratos Zucker , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Desacopladora 2 , Proteína Desacopladora 3
6.
J Endocrinol Invest ; 25(10): 905-14, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12508954

RESUMO

Obesity is a multi-factorial, chronic disorder that has reached epidemic proportions in most industrialized countries and is threatening to become a global epidemic. Obese patients are at a higher risk from coronary artery disease, hypertension, hyperlipidemia, diabetes mellitus, certain cancers, cerebrovascular accidents, osteoarthritis, restrictive pulmonary disease, and sleep apnea. Obesity is a particularly challenging clinical condition to treat, because of its complex pathophysiological basis. Indeed, body weight represents the integration of many biological and environmental components. Efforts to develop innovative anti-obesity drugs have been recently intensified. In broad terms, researchers use different distinct strategies: first, to reduce energy intake; second, to increase energy expenditure; third, to alter the partitioning of nutrients between fat and lean tissue. In the present review we concentrate on the first of these strategies, by underlining the new pharmacological tools which are presently studied.


Assuntos
Depressores do Apetite/uso terapêutico , Obesidade/tratamento farmacológico , Animais , Fármacos Antiobesidade/uso terapêutico , Ciclobutanos/uso terapêutico , Indústria Farmacêutica/tendências , Humanos , Lactonas/uso terapêutico , Orlistate
7.
Int J Obes Relat Metab Disord ; 25(10): 1421-30, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11673761

RESUMO

OBJECTIVE: To elucidate the effects and molecular mechanism(s) by means of which noradrenaline (NA) protects against the tumor necrosis factor (TNF)-alpha-induced apoptosis of brown adipocytes. DESIGN: Brown fat precursor cells were isolated from young rats; 2.5 million cells were added to each 24-well culture plate and cultured in a defined culture medium. On day 8, the cultured cells were exposed to murine recombinant TNF-alpha and/or cycloheximide (CHX; 10 microg/ml) and/or NA and/or nitric oxide (NO) donors and/or the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) and/or 10 microM heat shock protein 70 (HSP70) antisense or sense oligomers. MEASUREMENTS: Analysis of DNA fragmentation on agarose gel as a marker of apoptosis; reverse transcriptase-polymerase chain reaction analysis of mRNA levels; Western blotting analysis of protein levels. RESULTS: Pretreatment of primary cultures of rat brown fat cells with micromolar concentrations of NA or the NO-donor S-nitroso-N-acetylpenicillamine (SNAP) induced the expression of HSP70 mRNA and protein, which was associated with cytoprotection against TNF-alpha plus CHX-induced apoptosis. The L-NAME inhibitor of NO synthase activity inhibited both NA-stimulated HSP70 expression and cytoprotection. Furthermore, pretreatment of brown adipocytes with an antisense oligonucleotide to HSP70 antagonized both SNAP- and NA-induced cytoprotection. CONCLUSION: These findings demonstrate that the NO produced by NA stimulation can induce resistance to the TNF-alpha-induced apoptosis of brown adipocytes, possibly by means of the expression of HSP70.


Assuntos
Tecido Adiposo Marrom/metabolismo , Apoptose/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/metabolismo , Óxido Nítrico/farmacologia , Norepinefrina/farmacologia , Animais , Western Blotting , Células Cultivadas , Cicloeximida/farmacologia , Fragmentação do DNA , Eletroforese em Gel de Ágar , Proteínas de Choque Térmico HSP70/efeitos dos fármacos , Masculino , Compostos Nitrosos , Oligonucleotídeos Antissenso/farmacologia , Inibidores da Síntese de Proteínas , RNA Mensageiro/metabolismo , Ratos , Ratos Zucker , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/farmacologia
8.
Diabetes ; 50(3): 601-8, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11246880

RESUMO

The preferential channeling of different fuels to fat and changes in the transcription profile of adipose tissue and skeletal muscle are poorly understood processes involved in the pathogenesis of obesity and insulin resistance. Carbohydrate and lipid metabolism may play relevant roles in this context. Freely moving lean Zucker rats received 3- and 24-h infusions of Intralipid (Pharmacia and Upjohn, Milan, Italy) plus heparin, or saline plus heparin, to evaluate how an increase in free fatty acids (nonesterified fatty acid [NEFA]) modulates fat tissue and skeletal muscle gene expression and thus influences fuel partitioning. Glucose uptake was determined in various tissues at the end of the infusion period by means of the 2-deoxy-[1-3H]-D-glucose technique after a euglycemic-hyperinsulinemic clamp: high NEFA levels markedly decreased insulin-mediated glucose uptake in red fiber-type muscles but enhanced glucose utilization in visceral fat. Using reverse transcriptase-polymerase chain reaction and Northern blotting analyses, the mRNA expression of fatty acid translocase (FAT)/CD36, GLUT4, tumor necrosis factor (TNF)-alpha, peroxisome proliferator-activated receptor (PPAR)-gamma, leptin, uncoupling protein (UCP)-2, and UCP-3 was investigated in different fat depots and skeletal muscles before and after the study infusions. GLUT4 mRNA levels significantly decreased (by approximately 25%) in red fiber-type muscle (soleus) and increased (by approximately 45%) in visceral adipose tissue. Furthermore, there were marked increases in FAT/CD36, TNF-alpha, PPAR-gamma, leptin, UCP2, and UCP3 mRNA levels in the visceral fat and muscle of the treated animals in comparison with those measured in the saline-treated animals. These data suggest that the in vivo gene expression of FAT/CD36, GLUT4, TNF-alpha, PPAR-gamma, leptin, UCP2, and UCP3 in visceral fat and red fiber-type muscle are differently regulated by circulating lipids and that selective insulin resistance seems to favor, at least in part, a prevention of fat accumulation in tissues not primarily destined for fat storage, thus contributing to increased adiposity and the development of a prediabetic syndrome.


Assuntos
Tecido Adiposo/metabolismo , Metabolismo Energético , Ácidos Graxos não Esterificados/farmacocinética , Músculo Esquelético/metabolismo , Tecido Adiposo/fisiologia , Animais , Emulsões Gordurosas Intravenosas/farmacocinética , Emulsões Gordurosas Intravenosas/farmacologia , Expressão Gênica/efeitos dos fármacos , Técnica Clamp de Glucose , Heparina/farmacologia , Masculino , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/fisiologia , Ratos , Ratos Zucker , Vísceras
9.
Int Clin Psychopharmacol ; 16(1): 27-32, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11195257

RESUMO

A 6-week double-blind placebo-controlled trial was carried out to examine the efficacy and tolerability of moclobemide, a monoamine oxidase type A selective and reversible inhibitor, in the treatment of bulimia nervosa. Patients were admitted to the study even if they were unable to adhere to a tyramine-free diet. Fifty-two normal-weight women (age range 18-40 years) suffering from bulimia nervosa (DSM-IV criteria) completed the trial. Particular emphasis was placed on evaluating the incidence of hypertension and other side-effects in chronically treated patients. At the usual antidepressant dose of 600 mg, moclobemide was not significantly superior to placebo in the reducing the weekly number of binge eating episodes or in improving several measures of eating attitudes and behaviour (BITE, EDI, TFEQ) in normal-weight bulimia nervosa. The dropout rate was relatively low (29%), and the side-effects were limited and equally distributed between the two treatment groups. No patient experienced a hypertensive crisis during the study and no serious side-effect was detected. The study indicates that moclobemide 600 mg pro die is not efficacious in bulimia nervosa, but it can be safely administered, even to young subjects, at a very high risk of consuming large amounts of tyramine-rich foods without dietary restrictions.


Assuntos
Bulimia/tratamento farmacológico , Moclobemida/uso terapêutico , Adolescente , Adulto , Bulimia/diagnóstico , Bulimia/psicologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Moclobemida/efeitos adversos , Falha de Tratamento , Resultado do Tratamento
10.
Proc Natl Acad Sci U S A ; 97(14): 8033-8, 2000 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-10884431

RESUMO

Severe quantitative and qualitative brown adipocyte defects are common in obesity. To investigate whether aberrant expression of tumor necrosis factor alpha (TNF-alpha) in obesity is involved in functional brown fat atrophy, we have studied genetically obese (ob/ob) mice with targeted null mutations in the genes encoding the two TNF receptors. The absence of both TNF receptors or p55 receptor alone resulted in a significant reduction in brown adipocyte apoptosis and an increase in beta(3)-adrenoreceptor and uncoupling protein-1 expression in obese mice. Increased numbers of multilocular functionally active brown adipocytes, and improved thermoregulation was also observed in obese animals lacking TNF-alpha function. These results indicate that TNF-alpha plays an important role in multiple aspects of brown adipose tissue biology and mediates the abnormalities that occur at this site in obesity.


Assuntos
Adipócitos/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Apoptose , Obesidade/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Adaptação Fisiológica , Adipócitos/citologia , Tecido Adiposo Marrom/citologia , Animais , Antígenos CD/genética , Temperatura Corporal , Proteínas de Transporte/metabolismo , Temperatura Baixa , AMP Cíclico/biossíntese , Marcação In Situ das Extremidades Cortadas , Canais Iônicos , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Mutantes , Proteínas Mitocondriais , Mutação , Receptores Adrenérgicos beta/metabolismo , Receptores Adrenérgicos beta 3 , Receptores do Fator de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Desacopladores/metabolismo , Proteína Desacopladora 1
11.
Diabetes ; 49(3): 319-24, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10868951

RESUMO

Little is known about the mechanisms involved in the preferential channeling of different fuels to fat and how the target tissue participates in this process. Dietary fatty acids have been shown to act as signaling molecules that bind and activate a new class of nuclear receptors, the peroxisome proliferator-activated receptors (PPARs). PPAR-gamma is particularly interesting because it may have the potential to link particular fatty acids with a program of gene expression involved in lipid storage and metabolism. We investigated whether a nutrient-sensing pathway is activated by an increased availability of lipid fuels in nine normal weight male volunteers. Using reverse transcriptase-polymerase chain reaction analysis, the mRNA expression of fatty acid translocase (FAT)/CD36, PPAR-gamma2, leptin, uncoupling protein (UCP)-2 and UCP-3, and tumor necrosis factor (TNF)-alpha was investigated in gluteal subcutaneous fat biopsies before and after 5 h infusions of saline or Intralipid (Pharmacia and Upjohn, Milan, Italy) plus heparin, which does not modify insulinemia. Marked increases in FAT/CD36 (724+/-18%; P < 0.05), PPAR-gamma2 (200+/-8%; P < 0.05), leptin (110+/-13%; P < 0.05), UCP-2 (120+/-7%; P < 0.05), UCP-3 (80+/-5%; P < 0.05), and TNF-alpha mRNA (130+/-12%; P < 0.05) were observed in comparison with pretreatment levels, whereas there was no change after saline infusion. These data suggest that the in vivo gene expression of FAT/CD36, PPAR-gamma2, leptin, UCP-2, UCP-3, and TNF-alpha in subcutaneous adipose tissue is regulated by circulating lipids independent of insulin and that prolonged hyperlipidemia may therefore contribute to increased fat metabolism and storage as a result of the increased expression of these proteins.


Assuntos
Tecido Adiposo/fisiologia , Emulsões Gordurosas Intravenosas/farmacologia , Expressão Gênica/efeitos dos fármacos , Transportadores de Ânions Orgânicos , Tecido Adiposo/citologia , Adulto , Nádegas , Antígenos CD36/genética , Proteínas de Transporte/genética , Ácidos Graxos não Esterificados/sangue , Humanos , Infusões Intravenosas , Insulina/sangue , Canais Iônicos , Masculino , Glicoproteínas de Membrana/genética , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Proteínas Mitocondriais , Oxirredução , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores para Leptina , Pele , Especificidade por Substrato , Fatores de Transcrição/genética , Fator de Necrose Tumoral alfa/genética , Proteína Desacopladora 1
12.
FEBS Lett ; 487(2): 171-5, 2000 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-11150503

RESUMO

To investigate whether brown adipose tissue (BAT) expresses the inducible (HO-1) and the constitutive (HO-2) isoform of heme oxygenase, reverse transcriptase-polymerase chain reaction, Western blotting and immunohistochemistry were performed on interscapular BAT (IBAT) from rats acclimated at environmental temperature or exposed to cold. Both HO isoforms were detected in rat IBAT. They were immunolocalized in the cytoplasm and/or nuclei of brown adipocytes, in parenchymal capillaries, arteries and in some veins and nerves. Whereas cold exposure did not affect HO-2 expression, it significantly increased the expression of HO-1, both at mRNA (about 3-fold) and protein (about 2-fold) levels, reflecting the increased expression of HO-1 in the brown adipocytes and endothelial cells of parenchymal capillaries. Western blotting of cytosolic and nuclear protein extracts from cultured differentiated brown adipocytes showed that HO-1 and HO-2 are indeed localized in the cytosol and nuclei of brown adipocytes, and that noradrenaline stimulation significantly increased their amount in cytosol but not in the nuclear fraction.


Assuntos
Adipócitos/enzimologia , Tecido Adiposo Marrom/enzimologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Heme Oxigenase (Desciclizante)/genética , Aclimatação , Adipócitos/citologia , Tecido Adiposo Marrom/citologia , Animais , Núcleo Celular/enzimologia , Células Cultivadas , Temperatura Baixa , Citoplasma/enzimologia , Citosol/enzimologia , Heme Oxigenase (Desciclizante)/análise , Heme Oxigenase-1 , Biossíntese de Proteínas , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Temperatura , Transcrição Gênica
13.
Obes Rev ; 1(2): 127-39, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12119986

RESUMO

Sibutramine is a combined serotonin(5-HT) and noradrenaline (NA)re-uptake inhibitor. Sibutramine works predominantly through its two pharmacologically active metabolites (i.e. primary and secondary amines) which induce marked weight loss by affecting both food intake and energy expenditure. It is able to enhance the physiological process of satiety, and to stimulate thermogenesis, increasing the efferent sympathetic activity to thermogenically active brown fat. There is a dose-related reduction in body weight in clinical trials with sibutramine, with weight loss up to 11% below baseline, which can last up to 18 months with continued treatment. When weight loss is induced with a very low calorie diet (VLCDL), patients randomized to the sibutramine treatment continued to lose weight over a 1 year period, reaching 15% below baseline, whereas the placebo-treated patients regained some weight. Sibutramine improves metabolic fitness, by decreasing the biochemical risk factors associated with obesity, such as plasma triglycerides, total cholesterol and low density lipoprotein (LDL) cholesterol, glucose and insulin, and increasing HDL-cholesterol. In controlled studies, 84% of sibutramine-treated patients reported side effects, most commonly including dry mouth, constipation and insomnia, compared with 71% of patients receiving placebo. A small increase in heart rate and blood pressure also occurs and persists for as long as treatment is continued, which, therefore, requires monitoring. Nevertheless, successful treatment of moderately hypertensive obese patients with sibutramine has been demonstrated without undue blood pressure problems and even a mean lowering of blood pressure associated with weight loss. Finally, sibutramine does not have the potential for abuse that is characteristic of amphetamine and it is indistinguishable from placebo in abuse potential studies.


Assuntos
Fármacos Antiobesidade/efeitos adversos , Fármacos Antiobesidade/uso terapêutico , Ciclobutanos/efeitos adversos , Ciclobutanos/uso terapêutico , Obesidade/tratamento farmacológico , Fármacos Antiobesidade/farmacocinética , Monoaminas Biogênicas/metabolismo , Ciclobutanos/química , Ciclobutanos/farmacocinética , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Humanos , Relação Estrutura-Atividade , Termogênese/efeitos dos fármacos , Redução de Peso
15.
FEBS Lett ; 442(2-3): 167-72, 1999 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9928995

RESUMO

The thermogenic activity of brown adipose tissue (BAT) is heavily dependent on high perfusion, through its dense vascular system. Angiogenesis must go hand-in-hand with BAT functions, but little is known about the factors controlling it. In the present study we demonstrate that: (a) vascular endothelial growth factor (VEGF) is synthesised and released in brown adipocytes in culture; (b) VEGF mRNA isoforms and protein appear in dispersed mature brown adipocytes and whole tissue; (c) VEGF expression is increased in BAT from cold-exposed rats, and in cultured brown adipocytes exposed to noradrenaline and the beta3-adrenoceptor agonists; (e) BAT from genetically obese (falfa) rats exhibits reduced expression of VEGF as well as a change in the ratio of mRNA isoforms. It is concluded that sympathetic control of VEGF expression via noradrenaline acting on beta3-adrenoceptors plays a major role in developmental and adaptive angiogenesis, and defects in this contribute to the reduced thermogenic capacity of BAT in genetic obesity.


Assuntos
Tecido Adiposo Marrom/metabolismo , Fatores de Crescimento Endotelial/metabolismo , Regulação da Expressão Gênica , Linfocinas/metabolismo , Obesidade/metabolismo , Sistema Nervoso Simpático/metabolismo , Tecido Adiposo Marrom/irrigação sanguínea , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/imunologia , Agonistas Adrenérgicos beta/farmacologia , Animais , Células Cultivadas , Temperatura Baixa , Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Linfocinas/genética , Linfocinas/imunologia , Masculino , Neovascularização Fisiológica , Norepinefrina/farmacologia , Obesidade/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Ratos Zucker , Receptores Adrenérgicos beta/fisiologia , Receptores Adrenérgicos beta 3 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
16.
Br J Pharmacol ; 125(4): 888-94, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9831929

RESUMO

1. In the present work, we study the effect of NO on the proliferation and differentiation of brown fat cells in primary cultures. 2. Brown fat precursor cells isolated from rat brown adipose tissue were cultured for 8 days until confluence and treated daily with the NO donating agents, S-nitroso-acetyl penicillamine (SNAP) or S-nitroso-L-glutathione (GSNO). Both agents (300 microM) decreased cell proliferation approximately 8 fold on day 8. The inhibitory effect of NO was unlikely to be due to cytotoxicity since (i) cells never completely lost their proliferation capacity even after 8 days of exposure to repeated additions of SNAP or GSNO, and (ii) the inhibitory effect was reversible after removal of the media containing NO donors. 3. Daily treatment with nitric oxide synthase inhibitors, such as NG-nitro-L-arginine methyl ester (L-NAME, 300 microM), led to the stimulation of cell proliferation by 44+/-5%, n=3, suggesting that NO, endogenously produced in brown adipocytes, may be involved in modulating cell growth. 4. Daily treatment with both SNAP or GSNO induced significant mitochondriogenesis, measured as the mitochondrial conversion of 3-[4,5-dimethylthiazol-2-yl-]-2,5-diphenyl tetrazolium bromide (MTT) to formazan, whilst daily treatment with L-NAME was without effect. 5. The inhibition of cell proliferation by NO donors was accompanied by the expression of two genes coding for peroxisome proliferator activated receptor-gamma and uncoupling protein-1, which are upregulated during differentiation. 6. Increasing cyclic GMP in cells by 8-bromo-cyclic GMP (100-1000 microM) did not reproduce the observed NO effects on either cell number or gene expression. On the other hand, chronic treatment with the inhibitor of the NO-stimulated guanylyl cyclase, 1H-[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one (ODQ), reduced the expression of peroxisome proliferator activated receptor-gamma and uncoupling protein-1.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico/farmacologia , Animais , Sequência de Bases , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , GMP Cíclico/análogos & derivados , GMP Cíclico/farmacologia , Glutationa/análogos & derivados , Glutationa/farmacologia , Masculino , Dados de Sequência Molecular , NG-Nitroarginina Metil Éster/farmacologia , Compostos Nitrosos/farmacologia , Penicilamina/análogos & derivados , Penicilamina/farmacologia , Ensaio de Radioimunoprecipitação , Ratos , Ratos Sprague-Dawley , S-Nitrosoglutationa , Fatores de Tempo
17.
Eur J Pharmacol ; 352(1): 125-9, 1998 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-9718277

RESUMO

Experimental evidence suggests that, by stimulating energy expenditure in brown fat, selective beta3-adrenoceptor agonists can reduce body weight in obese rodents. In order to investigate further the physiological role of beta3-adrenoceptors in brown adipocytes, we analysed the effects of selective beta3-adrenoceptor agonists and antagonists on uncoupling protein-1 and leptin gene expression in culture-differentiated brown fat cells. Our main findings were that: (i) the leptin gene is expressed in brown adipocytes; (ii) the selective beta3-adrenoceptor agonist, N[(2S)-7-carbethoxy-1,2,3,4-tetrahydronaphth-2-yl]-(2R)-2-hydroxy- 2-(3-chlorophenil)ethanamine hydrochloride (SR58611A), inhibits leptin gene while inducing uncoupling protein-1 gene expression; (iii) these opposite effects of SR58611A are antagonized by the selective beta3-adrenoceptor antagonist, SS-enantiomer 3-(2-ethylphenoxy)-1-(1S),2,3,4-tetrahydronaphth-1-ylamin ol]-(2S)-2-propanol oxalate (SR59230A), but not by the selective beta1-adrenoceptor antagonist (+/-)-[2-(3-carbamoyl-4-hydroxyphenoxy)-ethylamino]-3-[4(1-methyl- 4-trifluoromethyl-2-imidazolyl)-phenoxy]-2 propanol (CGP20712A); and (iv) these effects are due to increased cyclic AMP levels. These results confirm by means of a different experimental approach that beta3-adrenoceptors play a central role in controlling the expression of genes that are important for brown fat function.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Agonistas Adrenérgicos beta/farmacologia , Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Propanolaminas/farmacologia , Proteínas/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/metabolismo , Animais , Sequência de Bases , Células Cultivadas , Primers do DNA , Canais Iônicos , Leptina , Masculino , Proteínas Mitocondriais , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta/efeitos dos fármacos , Receptores Adrenérgicos beta 3 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Desacopladora 1
18.
FEBS Lett ; 431(1): 80-4, 1998 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-9684870

RESUMO

Obesity is linked to functional brown adipose tissue (BAT) atrophy, partially due to adipocyte apoptosis. The brown adipocytes of obese rats have lower Bcl-2/Bax mRNA and protein ratios than those of their lean littermates. Exposure to a low temperature for three days markedly increased the Bcl-2/Bax ratio, by increasing the noradrenergic output to BAT, which has previously been shown to reduce apoptotic cell death. This effect could be mimicked in vitro by the addition of noradrenaline (NA) to brown adipocytes differentiated in culture. Micromolar NA concentrations increased the Bcl-2/Bax mRNA and protein ratios, and protected against serum deprivation-induced apoptosis. We conclude that NA acts by modulating bcl-2 and bax gene expression.


Assuntos
Tecido Adiposo Marrom/patologia , Apoptose , Obesidade/patologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Meios de Cultura Livres de Soro , Regulação da Expressão Gênica , Masculino , Norepinefrina/farmacologia , Obesidade/genética , Obesidade/metabolismo , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Zucker , Temperatura , Fator de Necrose Tumoral alfa/farmacologia , Proteína X Associada a bcl-2
20.
Neurosci Lett ; 246(1): 5-8, 1998 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-9622194

RESUMO

An analysis was made of the expression of nerve growth factor (NGF) mRNA and protein in the brown fat of rats at different ages, and the results compared with the expression of beta3-adrenoceptor and uncoupling protein 1 (UCP1). NGF, beta3-adrenoceptor, and UCP1 messenger RNA and protein levels were measured by means of reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting in the brown fat of rats at different ages (from 20-day-old fetuses (E20) to 16-month-old rats). During the perinatal period, NGF production increased and then declined to adult levels (which are comparable with fetal levels) by eight months, and remained stable thereafter. Relatively low levels of NGF were present in the brown fat of aged rats. Taken together, these results suggest that NGF may be responsible for regulating sympathetic innervation during the perinatal and adult periods.


Assuntos
Tecido Adiposo Marrom/metabolismo , Proteínas de Transporte/biossíntese , Proteínas de Membrana/biossíntese , Fatores de Crescimento Neural/biossíntese , Receptores Adrenérgicos beta/biossíntese , Tecido Adiposo Marrom/embriologia , Envelhecimento , Animais , Western Blotting , Canais Iônicos , Masculino , Proteínas Mitocondriais , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos beta 3 , Fatores de Tempo , Transcrição Gênica , Proteína Desacopladora 1
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