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1.
J Endocrinol Invest ; 47(6): 1361-1371, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38630213

RESUMO

AIM: This guideline (GL) is aimed at providing a clinical practice reference for the management of adult patients with overweight or obesity associated with metabolic complications who are resistant to lifestyle modification. METHODS: Surgeons, endocrinologists, gastroenterologists, psychologists, pharmacologists, a general practitioner, a nutritionist, a nurse and a patients' representative acted as multi-disciplinary panel. This GL has been developed following the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. A systematic review and network meta-analysis was performed by a methodologic group. For each question, the panel identified potentially relevant outcomes, which were then rated for their impact on therapeutic choices. Only outcomes classified as "critical" and "important" were considered in the systematic review of evidence. Those classified as "critical" were considered for clinical practice recommendations. Consensus on the direction (for or against) and strength (strong or conditional) of recommendations was reached through a majority vote. RESULTS: The present GL provides recommendations about the role of both pharmacological and surgical treatment for the clinical management of the adult patient population with BMI > 27 kg/m2 and < 40 kg/m2 associated with weight-related metabolic comorbidities, resistant to lifestyle changes. The panel: suggests the timely implementation of therapeutic interventions in addition to diet and physical activity; recommends the use of semaglutide 2.4 mg/week and suggests liraglutide 3 mg/day in patients with obesity or overweight also affected by diabetes or pre-diabetes; recommends semaglutide 2.4 mg/week in patients with obesity or overweight also affected by non-alcoholic fatty liver disease; recommends semaglutide 2.4 mg/week as first-line drug in patients with obesity or overweight that require a larger weight loss to reduce comorbidities; suggests the use of orlistat in patients with obesity or overweight also affected by hypertriglyceridemia that assume high-calorie and high-fat diet; suggests the use of naltrexone/bupropion combination in patients with obesity or overweight, with emotional eating; recommends surgical intervention (sleeve gastrectomy, Roux-en-Y gastric bypass, or metabolic gastric bypass/gastric bypass with single anastomosis/gastric mini bypass in patients with BMI ≥ 35 kg/m2 who are suitable for metabolic surgery; and suggests gastric banding as a possible, though less effective, surgical alternative. CONCLUSION: The present GL is directed to all physicians addressing people with obesity-working in hospitals, territorial services or private practice-and to general practitioners and patients. The recommendations should also consider the patient's preferences and the available resources and expertise.


Assuntos
Obesidade , Sobrepeso , Humanos , Obesidade/terapia , Obesidade/complicações , Obesidade/epidemiologia , Sobrepeso/terapia , Sobrepeso/complicações , Sobrepeso/epidemiologia , Adulto , Itália/epidemiologia , Comorbidade , Terapia Comportamental/métodos , Terapia Comportamental/normas , Guias de Prática Clínica como Assunto/normas , Gerenciamento Clínico , Cirurgia Bariátrica/métodos
2.
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
3.
J Endocrinol Invest ; 30(7): 610-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17848846

RESUMO

Dipeptidyl peptidase 4 (DPP-4) inhibitors are a new pharmacological class of drugs for treating Type 2 diabetes. They improve the capacity of the organism to control glycemia by increasing the levels of active incretins. Their mechanism of action is thus radically different from those of other anti-diabetic drugs currently available. DDP-4 inhibitors use a physiological mechanism to control hyperglycemia, by stimulating the secretion of insulin from beta-cells, decreasing the secretion of glucagon from pancreatic alpha-cells, and at the same time reducing the production of glucose by the liver. DDP-4 inhibitors have shown significant efficacy in maintaining reduced levels of glycosylated hemoglobin for up to 1 year. In vitro and animal studies have shown that they can inhibit apoptosis of beta-cells and favor their regeneration and differentiation. The oral DPP-4 inhibitors vildagliptin, sitagliptin, and saxagliptin are efficacious both alone and in association with other oral anti-diabetic agents and may be administered in a single daily dose. Lastly, they have substantial advantages with respect to other anti-diabetic drugs, since they involve a low risk of hypoglycemia and do not affect body weight.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico , Animais , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 2/metabolismo , Dipeptidil Peptidase 4 , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Células Secretoras de Glucagon/efeitos dos fármacos , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Inibidores de Proteases/efeitos adversos
4.
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
7.
Cell Death Differ ; 4(8): 771-8, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16465289

RESUMO

Accumulating evidence demonstrates that adipose tissue is a major site of tumor necrosis factor-alpha (TNF-alpha) gene expression, which is markedly high in obese animals and may contribute to obesity-linked insulin resistance. We now report that recombinant murine TNF-alpha triggers the apoptotic degeneration of brown adipocytes differentiated in culture. Moreover, noradrenaline, which has been described as having trophic effects on brown fat and accelerating the differentiation of brown adipocytes, is capable of dose-dependently preventing the TNF-alpha-induced apoptosis of brown fat cells. Since obesity is characterized by greatly increased TNF-alpha production and reduced catecholaminergic activity, apoptosis was studied in the brown fat of genetically obese animals. In situ DNA fragmentation analysis revealed a larger number of apoptotic cells in the brown fat of obese (fa/fa) than in that of lean (+/+) Zucker rats. The exposure of obese rats to low temperatures for 7 days, which increases the sympathetic activity of brown adipose tissue, significantly reduces the number of apoptotic brown adipocytes. We hypothesize that TNF-alpha may play a significant role in the control of brown fat homeostasis.

8.
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
9.
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
10.
Endocrinology ; 137(2): 495-503, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8593794

RESUMO

The presence of nerve growth factor (NGF) and the ability of adrenergic stimulation to affect the rate of its synthesis in mouse, rat, and human brown adipose tissue (BAT) were investigated. Addition of conditioned medium, obtained from preconfluent and confluent brown adipocytes, to PC12 cells induced typical morphological changes similar to those due to NGF itself. Anti-NGF antibodies blocked this action. Moreover, NGF mRNA was detected by RT-PCR both in BAT and in brown adipocyte preparations. That NGF is synthesized in and released from brown fat cells was confirmed by immunoblotting. When the animals were exposed to low temperatures, NGF production declined. The effect of cold exposure could be mimicked by the addition of norepinephrine (NE) at day 4 or 8 (preconfluent and confluent cells, respectively). NE depletion obtained by reserpine injection induced a drastic increase of BAT NGF production. In both rat and human BAT, immunohistochemistry identified distinct anatomical structures that express the low affinity neurotropin receptor, termed p75NGFR. BAT production of NGF was higher in genetically obese rats and mice than in their lean counterparts, a difference that becomes more evident with age. Prolonged exposure to low temperature significantly decreased the BAT NGF synthesis also in obese animals. We conclude that NGF is synthesized in and released from brown fat cells, its production being inversely dependent on sympathetic activity, in both physiological and pathophysiological conditions, and increased in genetic animal models of obesity.


Assuntos
Tecido Adiposo Marrom/metabolismo , Regulação da Temperatura Corporal/fisiologia , Fatores de Crescimento Neural/metabolismo , Obesidade/metabolismo , Tecido Adiposo Marrom/citologia , Animais , Sequência de Bases , Células Cultivadas , Feminino , Humanos , Lactente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Norepinefrina/farmacologia , Sondas de Oligonucleotídeos/genética , Células PC12 , Ratos , Ratos Zucker , Receptores de Fator de Crescimento Neural/metabolismo
11.
Endocrinology ; 119(5): 2227-32, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3533523

RESUMO

Dopamine (DA) may participate in the control of aldosterone secretion. We report that two different receptors for DA are present in rat adrenal glomerulosa: D-1, associated with stimulation of adenylate cyclase, and D-2, whose action inhibits adenylate cyclase. The adenylate cyclase system was stimulated by DA (EC50, 7.2 microM) and different DA agonists. When the D-1 receptor blocker SCH 23390 was added to the incubation medium, DA elicited a dose-dependent inhibition of adenylate cyclase (IC50, 10 microM); (-)sulpiride specifically blocked this effect. Furthermore, DA blocked angiotensin II-induced aldosterone release from glomerulosa slices in vitro. This effect was prevented by (-)sulpiride, but not by SCH 23390. The results suggest that the D-2 receptor acts to inhibit the cAMP-generating system and may be physiologically involved in the regulation of aldosterone secretion.


Assuntos
Córtex Suprarrenal/metabolismo , Aldosterona/metabolismo , Receptores Dopaminérgicos/fisiologia , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina , Adenilil Ciclases/metabolismo , Animais , Benzazepinas/farmacologia , Bromocriptina/farmacologia , Di-Hidroergotoxina/farmacologia , Haloperidol/farmacologia , Lisurida/farmacologia , Masculino , Ratos , Ratos Endogâmicos , Estereoisomerismo , Sulpirida/farmacologia
12.
Endocrinology ; 138(2): 676-82, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9003002

RESUMO

Exposure of rat brown adipocytes differentiated in culture to norepinephrine (NE) results in the production of nitrites (NO2-), the breakdown product of nitric oxide (NO). This production, which is blocked by actinomycin D1 is directly related to the duration of exposure to and dose of NE. Cytosol from NE-treated brown fat cells, but not from untreated cultures, catalyzed the Ca(2+)-independent conversion of L-arginine to L-citrulline, which could be significantly blocked by the specific nitric oxide synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester. Reverse transcriptase-PCR demonstrates that the addition of NE; selective beta 1-, beta 2-, or beta 3-adrenergic receptor agonists; or agents increasing cAMP production, such as forskolin, to brown adipocytes stimulates inducible NOS (iNOS) messenger RNA, which is present within 4 h after exposure. That iNOS is synthesized in brown fat cells is confirmed by immunoblotting using an antibody to the iNOS of mouse macrophages, Finally, in both brown adipose tissue (BAT) and brown adipocyte preparations from animals exposed to low temperature, iNOS messenger RNA and protein were expressed, and NOS activity was detectable; these findings were unlikely for room temperature-acclimated rats. We conclude that brown fat cells can express an inducible form of NOS similar to the iNOS of macrophages, and that its production is directly dependent on sympathetic activity in physiological conditions. NO generated by stimulation of iNOS in brown adipocytes may represent an important mechanism to modulate different BAT functions, among which is vasodilation of the BAT microcirculation.


Assuntos
Adipócitos/enzimologia , Tecido Adiposo Marrom/enzimologia , Óxido Nítrico Sintase/biossíntese , Tecido Adiposo Marrom/irrigação sanguínea , Animais , Arginina/metabolismo , Células Cultivadas , Citrulina/metabolismo , Dactinomicina/farmacologia , Indução Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Cinética , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Nitritos/metabolismo , Norepinefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional
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
14.
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
15.
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
16.
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
17.
Neuropharmacology ; 26(5): 477-80, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-2955241

RESUMO

With the aim of evaluating the possible functional modifications of both D1 and D2 dopamine receptor subpopulations after repeated administration of neuroleptics, the ability of selective D1 and D2 dopamine agonists to stimulate or inhibit, respectively, the activity of adenylate cyclase in the striatum and nucleus accumbens of rats treated with either saline or haloperidol for 21 days, was studied. It was found that stimulation of the activity of adenylate cyclase elicited by the selective D1 receptor agonist SKF 38393 was significantly greater in homogenates of striatum in rats treated with haloperidol, than in those of saline-treated rats. Similarly, the inhibitory effect on the activity of the enzyme elicited by the selective D2 agonist bromocriptine was much more evident in homogenates of the striatum from rats treated with neuroleptic than in those from saline-treated rats. When dopamine, sodium fluoride (NaF), or 5-guanylyl imidodiphosphate (Gpp(NH)p), were used as agonists to stimulate the activity of adenylate cyclase, the amount of cyclic AMP formed appeared the same in rats treated with haloperidol or saline. Dopamine receptors in nucleus accumbens behaved like those in the striatum in the pattern of modifications after repeated administration of haloperidol. Indeed, the inhibitory effect elicited by bromocriptine, as well as the stimulatory effect elicited by SKF 38393, was much more evident in nucleus accumbens from rats treated with haloperidol than in that from controls, whereas activation of adenylate cyclase induced by dopamine and sodium fluoride was similar in both experimental groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Adenilil Ciclases/metabolismo , Corpo Estriado/efeitos dos fármacos , Haloperidol/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Receptores Dopaminérgicos/efeitos dos fármacos , Núcleos Septais/efeitos dos fármacos , Animais , Corpo Estriado/enzimologia , Masculino , Núcleo Accumbens/enzimologia , Ratos , Ratos Endogâmicos , Receptores de Dopamina D1 , Receptores de Dopamina D2
18.
Neuropharmacology ; 24(3): 199-206, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-4039419

RESUMO

To investigate whether prolonged pretreatment with the dopamine (DA) agonist lisuride would result in modification of some of its behavioural effects, food intake, locomotor activity, body temperature or stereotyped and mounting behaviour were evaluated after acute injections of different doses of lisuride into rats, pretreated daily for four weeks with either saline or lisuride. Rats pretreated with lisuride developed tolerance to its anorexigenic and hypothermic effects, and reverse tolerance to its effects on locomotor activity, stereotyped and mounting behaviour. Pretreatment with lisuride did not modify the activity of drug-metabolizing enzymes in the liver. These results, in addition to revealing the pattern of the changes in the behavioural effects of a DA agonist drug, after repeated administration, may be taken as evidence for the existence of different DA receptor systems in different areas of the brain, that mediate different behavioural effects, and that differ markedly in their reactions to prolonged stimulation with an agonist drug.


Assuntos
Comportamento Animal/efeitos dos fármacos , Ergolinas/farmacologia , Lisurida/farmacologia , Receptores Dopaminérgicos/efeitos dos fármacos , Animais , Temperatura Corporal/efeitos dos fármacos , Tolerância a Medicamentos , Ingestão de Alimentos/efeitos dos fármacos , Humanos , Lisurida/administração & dosagem , Masculino , Microssomos Hepáticos/enzimologia , Oxigenases de Função Mista/metabolismo , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Estereotipado/efeitos dos fármacos
19.
Br J Pharmacol ; 48(2): 245-54, 1973 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-4733727

RESUMO

1. With isolated preparations of rat stomach fundus as well as of duodenum and ileum of rats and guinea-pigs, 5,6-dihydroxytryptamine and 5,6-diacetoxytryptamine caused a contraction which was antagonized by methysergide and lysergic acid diethylamide (LSD), but not by atropine. Pretreatment of the animals with reserpine did not decrease the effect of the two indoleamines on the isolated ileum and duodenum.2. In anaesthetized guinea-pigs, 5,6-dihydroxytryptamine and its diacetyl derivative caused bronchoconstriction which was antagonized by methysergide, but not modified by pretreating the animals with reserpine.3. In anaesthetized cats, 5,6-dihydroxytryptamine had, in general, a hypotensive effect which was reversed by hexamethonium.4. 5,6-Dihydroxytryptamine also caused aggregation of isolated rabbit and human platelets and inhibited the platelet aggregation induced by 5-hydroxytryptamine (5-HT) plus adrenaline.5. The pattern of action of 5,6-hydroxytryptamine and 5,6-diacetoxytryptamine was qualitatively the same as that of 5-HT, but the potency of the compounds decreased in the order 5-HT, 5,6-dihydroxytryptamine, 5,6-diacetoxytryptamine both in vitro and in vivo.6. It is concluded that 5,6-dihydroxytryptamine and its diacetyl derivative stimulate postsynaptic 5-HT receptors, but that their effect is weaker than that of 5-HT.


Assuntos
Serotonina/farmacologia , Triptaminas/farmacologia , Resistência das Vias Respiratórias/efeitos dos fármacos , Animais , Atropina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Brônquios/efeitos dos fármacos , Gatos , Relação Dose-Resposta a Droga , Duodeno/efeitos dos fármacos , Cobaias , Frequência Cardíaca/efeitos dos fármacos , Íleo/efeitos dos fármacos , Técnicas In Vitro , Iproniazida/farmacologia , Dietilamida do Ácido Lisérgico/farmacologia , Masculino , Metisergida/farmacologia , Contração Muscular/efeitos dos fármacos , Adesividade Plaquetária/efeitos dos fármacos , Ratos , Antagonistas da Serotonina , Estômago/efeitos dos fármacos , Fatores de Tempo , Triptaminas/antagonistas & inibidores
20.
Br J Pharmacol ; 56(4): 431-6, 1976 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1260223

RESUMO

1 Mazindol is a new anorexigenic agent which possesses a different chemical structure from that of phenylethylamines, but shows a pharmacological profile similar to that of (+)-amphetamine. 2 Mazindol neither altered whole brain monoamine levels (noradrenaline (NA), dopamine, 5-hydroxytryptamine (5-HT)) nor changed NA levels in the hypothalamus or dopamine levels in the caudate nucleus. 3 Mazindol enhanced dopamine turnover rate in the caudate nucleus, as shown by the increased rate of dopamine decline after blockade of catecholamine synthesis by alpha-methyl-p-tyrosine and decreased the conversion index of (3H)-tyrosine into brain NA. 4 Mazindol administration did not modify pargyline-induced decline of 5-hydroxyindoleacetic acid suggesting that 5-HT turnover is not altered by this drug.


Assuntos
Aminas Biogênicas/análise , Química Encefálica/efeitos dos fármacos , Indóis/farmacologia , Mazindol/farmacologia , Animais , Aminas Biogênicas/metabolismo , Núcleo Caudado/metabolismo , Corpo Estriado/metabolismo , Dopamina/metabolismo , Ácido Hidroxi-Indolacético/metabolismo , Cinética , Masculino , Metiltirosinas/farmacologia , Norepinefrina/metabolismo , Pargilina/farmacologia , Ratos , Serotonina/metabolismo
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