The brain is the conductor: diet- induced inflammation overlapping physiological control of body mass and metabolism O cérebro é o maestro: inflamação induzida por dieta interfere no controle fisiológico da adiposidade corporal e do metabolismo

ABSTRACT Obesity is currently a worldwide pandemic. It affects more than 300 million humans and it will probably increase over the next 20 years. The consumption of calorie-rich foods is responsible for most of the obesity cases, but not all humans exposed to high-calorie diets develop the disease. This fact has prompted researchers to investigate the mechanisms linking the consumption of high-calorie diets to the generation of an imbalance between energy intake and expenditure. According to recent studies, the exposure to fat-rich diets induces an inflammatory response in the hypothalamic areas involved in the control of feeding and thermogenesis. The inflammatory process damages the neuronal circuitries that maintain the homeostatic control of the body's energy stores, therefore favoring body mass gain. This review will focus on the main advances obtained in this field. Arq Bras Endocrinol Metab. 2009;53(2):151-158. Keywords Inflammation; hypothalamus; metabolism; weight control; fat-rich diet RESUMO Obesidade é hoje um grave problema de saúde pública no mundo. Mais de 300 milhões de pessoas são obesas e esse número deve crescer substancialmente nos próximos 20 anos. As dietas ricas em calorias são a principal causa de obesidade, porém, nem todos os indivíduos expostos a dietas altamente calóricas se tornam obesos. Tal fato estimulou pesquisadores a investigarem os mecanismos que ligam o consumo de dietas ricas em calorias ao desenvolvimento de um balanço inadequado entre consumo e gasto energético. De acordo com estudos recentes, o consumo de dietas ricas em gorduras induz a ativação de uma resposta inflamatória nas áreas do hipotálamo envolvidas com o controle da fome e da termogênese. Tal processo inflamatório lesa os circuitos neuronais que mantêm o controle homeostático das reservas corporais de energia, favorecendo assim o ganho de massa adiposa. Esta revisão irá focar os principais avanços obtidos nesta área. Arq Bras Endocrinol Metab. 2009;53(2):151-158. Descritore

Novo modelo, velho remédio

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Neuroendokrynna regulacja masy ciała: integracja tkanki tłuszczowej, układu pokarmowego i mózgu

Human body weight is maintained at a fairly stable level regardless of changes in energy intake and energy expenditure. Compensatory mechanisms within the central nervous system (CNS), which regulate food intake and energy expenditure, are triggered by other central and peripheral signals. Peripherally, the main sources of those signals are the adipose tissue, gastrointestinal tract, and pancreas. The main signal originating from the adipose tissue is leptin, which promotes the activation of anorexigenic pathways in the CNS. Similarly, the central action of insulin also reduces food intake and stimulates catabolic pathways. The gastrointestinal tract contributes with several peptides that influence food intake, such as ghrelin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY), oxyntomodulin (OXM), and cholecystokinin (CCK). Other substances secreted by the pancreas, such as pancreatic polypeptide (PP) and amylin, a hormone co-secreted with insulin, also affect energy balance. More recently, the endocannabinoid system has also been identified as a contributor in the maintenance of energy balance. Better understanding of these mechanistic systems involved in the regulation of energy metabolism will hopefully lead to the development of new therapeutic approaches against obesity, metabolic syndrome, and other nutritional disorders. (Pol J Endocrinol 2010; 61 (2): 194-206)Masa ciała człowieka jest utrzymywana na względnie stałym poziomie niezależnie od zmian zarówno w dostarczaniu energii, jak i jej zużywania. Mechanizm kompensacyjny w ośrodkowym układzie nerwowym (CNS, central nervous system [OUN]), który reguluje przyjmowanie pokarmu i wydatek energii jest uruchamiany przez inne sygnały ośrodkowe i obwodowe. Obwodowo, źródłem tych sygnałów jest tkanka tłuszczowa, układ pokarmowy i trzustka. Głównym sygnałem pochodzącym z tkanki tuszczowej jest leptyna, która powoduje aktywację anoreksogennych dróg przekazu sygnału w CNS. Podobnie, oddziaływanie ośrodkowe insuliny także zmniejsza przyjmowanie pokarmu i stymuluje kataboliczne drogi przekazu sygnału. W układzie pokarmowym współdziała kilka peptydów, które wpływają na przyjmowanie pokarmu, takie jak grelina, peptyd podobny do glukagonu (GLP-1, glucagon-like peptide), peptyd YY (PYY, peptide YY), oksyntomodulina (OXM, oxyntomodulin) i cholecystokinina (CCK, cholecystokinin), Pozostałe substancje wydzielane przez trzustkę, takie jak polipeptyd trzustkowy (PP, pancreatic polypeptide) i amylina, hormon wydzielany jednocześnie z insuliną , także wpływają na równowagę energetyczną. W najnowszych badaniach stwierdzono, że układ endokannabinoidowy przyczynia sie do zachowania równowagi energetycznej. Lepsze zrozumienie mechanizmów układów wpływających na regulacje przemiany energii przyczyni się do rozwoju nowych terapii otyłości, zespołu metabolicznego i innych zaburzeń odżywiania. (Endokrynol Pol 2010; 61 (2): 194-206

Uso da cinza insolúvel em ácido para determinar o consumo de forragem dos bovinos

Six young crossbred bulls were used to determine dry matter intake by cattle fed a tropical grass hay (Cynodon dactylon, Coastcross 1). Digestion trial lasted for 23 days being the last 7 days for feed and feces sample collections. Dry matter intake was calculated by use of adequate formulas and indicator method. Dry matter intake was calculated by acid insoluble ash HCl 2N and concentrated HCl and also by direct consumption. There was no statistical difference among methods for dry matter consumption.Foram utilizados seis bovinos mestiços holandês/zebu, machos inteiros, com idade variando entre 16 e 33 meses. O alimento foi o feno de Cynodon dactylon hibrido Coasteross - 1. O período experimental teve duração de 23 dias, sendo os últimos sete dias para colheita das amostras de alimento e de fezes. O feno foi fornecido picado e à vontade em duas refeições, diariamente. O consumo de matéria seca pelo método do indicador, foi calculado usando fórmulas adequadas, delineamento estatístico foi o inteiramente cercalizado. Foram comparados os consumos de matéria seca pelos métodos da cinza insolúvel em ácido HCl concentrado, HCl 2N e também pelo consumo observado no experimento. Não houve diferença estatisticamente significativa nos consumos médios de matéria seca g/kg 0,75 /dia, entre os três métodos

Uso da cinza insolúvel em ácido como indicador natural para determinação da digestabilidade em bovinos

Six crossbred young bulls were used in a digestibility trial during 23 days being the last 7 days for feed and feces sample collections. Cynodon dactylon grass hay was the sole ration. Nutrient digestibility coefficients were calculated by total collection method and by HCl 2N and concentrated HCl, acid insoluble ash methods which were statistically different among them for dry matter, crude protein, crude fiber, crude energy and nitrogen-free extract when calculated by SCHNEIDER & FLATT (1975) or LUCAS (1952) formulas. By use of total feces collection, digestibility coefficients were not statistically different. These results show the validity of acid insoluble ash methods to determine digestibility of nutrients for tropical grass hay.Foram utilizados seis bovinos mestiços Holandês/Zebu, machos inteiros, com idade entre 16 e 33 meses, para ensaio de digestibilidade em gaiolas, que teve duração de 23 dias, sendo os 7 dias finais, para colheita das amostras de fezes e do alimento. O alimento constituiu-se de feno de Cynodon dactylon, hibrido Coastcross 1, o que foi fornecido picado à vontade, em dois arraçoamentos, diariamente, sendo que junto ao primeiro destes era acrescentada mistura mineral completa na base de 40 g para cada animal. Os cálculos dos coeficientes de digestibilidade dos nutrientes foram feitos de dois modos: pela fórmula de SCHNEIDER e FLATT (1975) e pela fórmula de LUCAS (1952). O delineamento experimental foi inteiramente casualizado, com aplicação do teste de Duncan. A recuperação fecal foi alta para os dois métodos aplicados: HCl 2N com 109,46% e HCl concentrado com 103,20%. Houve diferença estatisticamente significativa nos coeficientes de digestibilidade  da matéria seca, da proteína bruta, da fibra bruta, dos extrativos não nitrogenados e da energia bruta quando foram comparados os métodos de cinza insolúvel em ácido  HCl 2N , HCl concentrado e pelo método de colheita total de fezes. Apenas a fração de extrato etéreo não mostrou diferença estatística significativa nos coeficientes de digestibilidade, entre os métodos .Usando a recuperação de fezes observada no experimento, para o cálculo dos coeficientes de digestibilidade, não houve diferença estatisticamente significativa para qualquer dos nutrientes; comprovando assim, a validade do uso da cinza insolúvel em ácido, como indicador para determinar a digestibilidade dos nutrientes de gramínea tropical fornecida a bovinos

[hypothalamic Dysfunction In Obesity].

Obesity, defined as abnormal or excessive fat accumulation that may impair life quality, is one of the major public health problems worldwide. It results from an imbalance between food intake and energy expenditure. The control of energy balance in animals and humans is performed by the central nervous system (CNS) by means of neuroendocrine connections, in which circulating peripheral hormones, such as leptin and insulin, provide signals to specialized neurons of the hypothalamus reflecting body fat stores, and induce appropriate responses to maintain the stability of these stores. The majority of obesity cases are associated with central resistance to both leptin and insulin actions. In experimental animals, high-fat diets can induce an inflammatory process in the hypothalamus, which impairs leptin and insulin intracellular signaling pathways, and results in hyperphagia, decreased energy expenditure and, ultimately, obesity. Recent evidence obtained from neuroimaging studies and assessment of inflammatory markers in the cerebrospinal fluid of obese subjects suggests that similar alterations may be also present in humans. In this review, we briefly present the mechanisms involved with the loss of homeostatic control of energy balance in animal models of obesity, and the current evidence of hypothalamic dysfunction in obese humans.56341-5

Digestibilidade (aparente) e produção forrageira de um pasto de capim gordura (Melinis minutiflora, Pal de Beauv). Fase II. Período de inverno

A planta forrageira estudada foi proveniente de um pasto com área de 2,0 ha, formado em setembro de 1974, tendo recebido antes da semeadura uma aplicação de 1.700 Kg/ha de calcário dolomítico e, após o plantio 510 Kg/ha de sulfato de amônio. A partir de sua formação foi utilizado em pastejo rotacionado por vacas em lactação, até o dia 27 de setembro de 1977, quando foi efetuado um corte com roçadeira para padronização, visando o aproveitamento da rebrota para os estudos conduzidos. Os ensaios de digestibilidade e as estimativas de produção forrageira foram efetuados em média aso 240, 300 e 360 dias de idade do capim. Os dados de produção de forragem foram obtidos com doze amostras colhidas com o auxílio de um quadrado de ferro medindo 0,25m2, tendo sido observados os seguintes resultados: 1) aos 240 dias (29/09/77 a 26/05/78): 37.430 Kg/há de massa verde (MV) e 13.870 Kg/há de matéria seca (MS). 2) aos 300 dias (27/09/77 a 25/07/78): 20.930 Kg/ha de MV e 10.360 Kg/ha MS. 3) aos 360 dias (27/09/77 a 23/09/78): 15.200 Kg/ha de MV e 9.060 Kg/ha de MS. Os ensaios de digestibilidade (aparente) foram efetuados com três bovinos em gaiolas e os valores dos nutrientes digestíveis na MS a 100oC foram: 1) aos 240 dias: matéria seca digestível (MSD) = 12,7%; proteína digestível (PD) = zero; extrato etéreo digestível (EED) = 3,3%; fibra digestível (FD) = 20,9%; extrativos não nitrogenados digestíveis (ENND) = 20,4% e nutrientes digestíveis totais (NDT) = 44,6%. 2) aos 300 dias: MSD = 16,2%; PD = zero; EED = 2,4%; FD = 22,8%; ENND = 18,5% e NDT = 43,7%. 3) aos 360 dias: MSD = 26,1; PD = zero; EED = 0,7; FD = 23,8%; ENND = 20,0% e NDT = 44,5. Os valores de EED foram multiplicados pelo fator 2,25.A digestion trial was conducted in order to determine the nutritive value of molassesgrass (Melinis minutiflora, Pal de Beauv) during the dry season in Pirassununga State of São Paulo -Brazil. Three young  crossbred Holstein vs Zebu bulls were kept in cages during seven days for collection, after eight-day adaptation period to the forage. Fresh chopped grass was fed to the animals after 240, 300 and 360 days of grass growing periods. Digestible nutrients in the grass were as follows: after 240 days: (DDM-digestible dry material=12,7%; DP-digestible protein=zero; DEE-digestible ethereal extract=3,3%; DCF-digestible fibers=20,9%; DNFE-digestible unazotated extract=20,4% and TDN-total digestible nutrients=44,6%; after 300 days: DDM=16,5%; DP=zero; DEE=2,4%; DCF=22,8%; DNFE=18,5% and TDN=43,7%; after 360 days: DDM=26,0%; DP=zero; DEE=0,7%; DCF=23,8%; DNFE = 20,0% and TDN = 44,5%

Interleukin-6 expression by hypothalamic microglia in multiple inflammatory contexts: a systematic review

Interleukin-6 (IL-6) is a unique cytokine that can play both pro- and anti-inflammatory roles depending on the anatomical site and conditions under which it has been induced. Specific neurons of the hypothalamus provide important signals to control food intake and energy expenditure. In individuals with obesity, a microglia-dependent inflammatory response damages the neural circuits responsible for maintaining whole-body energy homeostasis, resulting in a positive energy balance. However, little is known about the role of IL-6 in the regulation of hypothalamic microglia. In this systematic review, we asked what types of conditions and stimuli could modulate microglial IL-6 expression in murine model. We searched the PubMed and Web of Science databases and analyzed 13 articles that evaluated diverse contexts and study models focused on IL-6 expression and microglia activation, including the effects of stress, hypoxia, infection, neonatal overfeeding and nicotine exposure, lipopolysaccharide stimulus, hormones, exercise protocols, and aging. The results presented in this review emphasized the role of injury-like stimuli, under which IL-6 acts as a proinflammatory cytokine, concomitant with marked microglial activation, which drive hypothalamic neuroinflammation. Emerging evidence indicates an important correlation of basal IL-6 levels and microglial function with the maintenance of hypothalamic homeostasis. Advances in our understanding of these different contexts will lead to the development of more specific pharmacological approaches for the management of acute and chronic conditions, like obesity and metabolic diseases, without disturbing the homeostatic functions of IL-6 and microglia in the hypothalamus.2019COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informação2013/07607-

Central role of obesity in endothelial cell dysfunction and cardiovascular risk

Atherosclerosis is the leading cause of mortality in the contemporary world. The critical role of the endothelial cells (EC) in vascular homeostasis, the metabolic changes that take place when the cell is activated, and the elements involved in these processes have been widely explored over the past years. Obesity and its impact, promoting a rise in blood levels of free fatty acids (FAs) are often associated with atherosclerosis and cardiovascular mortality. However, the mechanisms that promote cardiovascular structural changes and adaptive changes in the ECs, particularly in the context of obesity, are little known. Here, we reviewed studies that assessed the metabolic adaptations of healthy and dysfunctional ECs during exposure to FAs, as well as the epidemiological perspectives of cardiovascular structural changes in obesity. Finally, we explored the role of new agents - sphingolipids, dietary unsaturated fatty acids and sodium-glucose cotransporter-2 inhibitors (iSGLT2) - in atherosclerosis and their relationship with obesity.651879

Polpa seca de laranja versus milho desintegrado, em misturas concentradas para vacas em lactação

Twelve crossbred cows were used in a switch-back design, to evaluate partial or total substitution of ground com ears for dried orange pulp, in rations for milk production. No significant difference was detected among treatments, as far as milk production and fact content were concerned, even when concentrate mixture contained up 67% of dried orange pulp.Doze vacas mestiças em lactação foram usadas em um delineamento ­tipo SWITCH-BACK para analisar a possibilidade da substituição parcial ou total do milho desintegrado por polpa cítrica seca, na mistura de concentrados. As vacas permaneceram em regime de pastagens, e os resultados obtidos permitiram concluir que, na época das chuvas, vacas com níveis de produção média iguais a 13,0 kg de leite por dia, podem receber misturas concentradas com até 67% de polpa cítrica, em substituição ao milho desintegrado, sem quaisquer inconvenientes