Ce travail s'inscrit dans le cadre général de l'étude des mécanismes d'intégration des informations viscérales. Nous avons étudié la dépression synaptique à long terme (DLT) dans le noyau du tractus solitaire et sa modulation par le statut nutritionnel Dans la première étude, nous avons caractérisé une DLT au niveau du NTS. Cette DLT, déclenchée par la stimulation des afférences viscérales à basse fréquence, est exprimée au niveau de l’élément présynaptique. Elle met en jeu une libération d'endocannabinoïdes qui en agissant au niveau de l’élément présynaptique réduisent la probabilité de libération de glutamate. De manière surprenante l’élément postsynaptique ne semble jouer aucun rôle dans cette DLT. Elle nécessite une activation séquentielle des récepteurs NMDA, la libération d'anandamide et l'activation des récepteurs aux cannabinoïdes de type 1 (CB1) et l’activité de l’élément présynaptique. Nos résultats suggèrent que cette DLT pourrait être entièrement organisée dans le compartiment présynaptique des afférences viscérales. Dans une deuxième partie du travail, nous nous sommes intéressés à la modulation de cette DLT dépendante des endocannabinoïdes (DLT-eCBs) par le statut nutritionnel. La privation de nourriture pendant 24 h empêche l'induction de la DLT-eCBs par la stimulation des afférences viscérales. Ces effets sont mimés par l'activation des récepteurs à la ghréline au niveau du NTS. Une re-nutrition pendant 3h restaure la DLT-eCBs via l'action périphérique de la Cholécystokinine (CCK) et l'activation de la voie ERK. Au total ces travaux soulignent la forte plasticité des afférences viscérales en fonction du statut nutritionnel. / This work joins within the framework of studies about the mechanisms of integration of the visceral informations. We studied long term synaptic depression in the nucleus of tractus solitarii (NTS) and it's modulation during changes in the nutritional status. In the first study, we characterized a long-term synaptic depression (LTD) in the NTS. This LTD, triggered by low frequency stimulation of visceral afferents is expressed at the presynaptic level. It involves release of endocannabinoids that would eventually reduce glutamate release probability. Surprisingly the postsynaptic element seems to play no role in this LTD. It requires sequential activation of NMDA receptors, the release of anandamide and activation of the cannabinoids type 1 receptors (CB1) and presynaptic activation. Our results suggest that this LTD could be entirely organized at the presynaptic compartment of visceral afferents. In the second part of this work, we were interested on the modulation of this endocannabinoïds dependent long-term depression (eCBs-LTD) by the nutritional status. Food deprivation during 24 h prevents the induction of eCBs-LTD by the stimulation of visceral afferents. These effects are mimicked by the activation of ghrelin receptors in the NTS. 3 h refeeding restores the eCBs-LTD via peripheral action of cholecystokinin (CCK) and the activation of the ERK pathway. Altogether, this work emphasizes the high plasticity of visceral afferents and its regulation by the nutritional status.

Le choc septique, première cause de mortalité intra hospitalière en France, comporte deux phases chronologiques. Lors de la première phase, la mortalité est essentiellement liée aux altérations macro et micro-circulatoires et aux défaillances d’organes associées. Puis une phase d’immunodépression acquise peut suivre et rendre les patients plus sensibles aux infections nosocomiales aggravant la mortalité. Avant les années 2000, il était admis que la physiopathologie du sepsis était liée à un état pro-inflammatoire massif. Cependant, chez l’homme, l’échec voire l’effet délétère des thérapeutiques anti-inflammatoires a conduit la communauté scientifique à changer progressivement de paradigme. A partir des années 2000 le glissement des patients de l’état pro-inflammatoire vers un état anti-inflammatoire immunosuppresseur (immunoparalysie) a été démontré. En réalité, ces deux événements, schématiquement présentés de manière successive, se produisent concomitamment et coexistent chez le patient. La cachexie, une autre conséquence de l’augmentation précoce des médiateurs de l’inflammation lors du choc septique, est un facteur de morbidité supplémentaire chez l’homme. Aucun modèle animal de cachexie post-septique n’a été décrit à ce jour. Ce travail a consisté à développer des modèles murins de choc septique et de cachexie post-septique qui miment les différentes phases de la maladie humaine et en particulier l’immunoparalysie. La perte de poids observée nous a amené à nous interroger sur les effets du sepsis sur le muscle. Enfin nous avons évalué dans ces modèles l’expression d’AG (ghréline acylée) et UAG (ghréline non acylée), deux facteurs pronostics et anti-cachectisants / During sepsis, the organism is subjected to an infection. Its first immunological response will be an inflammation which is the source of numerous immunological and physiological modifications.This massive inflammation will be compensated almost simultaneously: the organism set a compensatory anti-inflammatory response in order to alleviate the deleterious effects of the release of pro-inflammatory cytokines on the organ, whether they are distant or not from the infectious site. This so called beneficial response actually turns out to be a real scourge for the host. Indeed this compensatory anti-inflammatory response is sustainable and will overtake the inflammation leading to a protracted immunoparalysis. This infection-induced immunosuppression is responsible for an increase in patients’ susceptibility to secondary nosocomial infections.Another compensatory mechanism called proteolysis will be set in response to the massive inflammation. This protein breakdown induces a supply of nutrients which are essentials for the organism. The furnished amino acids originate from skeletal muscles and in case of sepsis or any inflammatory disease, the organism is overrun. Therefore, proteolysis persists, leading to an important muscle wasting, named cachexia.Setting up a murine model of sepsis induced through a cecal ligation and puncture allowed the identification of several mechanisms involved in immunoparalysis. We point out a consistent and sustainable anti-inflammatory response with a lymphocyte anergia (reduced number and proliferative ability), and an increase of the total number of regulatory T cells. We also highlighted a bacterial load-dependent and cytokines-dependent mortality following a secondary pulmonary infection with Pseudomonas aeruginosa.Thanks to this model we also characterized septic cachexia. Despite several descriptions, formal evidences of cachexia during sepsis were lacking. Thus, the important weight loss of our animals, but especially their muscular loss after 13 days and their reduced fiber cross sectional areas could be used as a basis to an investigation of ubiquitin ligases pathway, the major actors of proteolysis. Beside classical MAFbx and MuRF1, many other ubiquitin ligases were upregulated during sepsis

Orientador: Bruno Geloneze Neto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-24T12:17:34Z (GMT). No. of bitstreams: 1 Cardozo_DanielaSchiavo_D.pdf: 1355414 bytes, checksum: 3c91c18e1699608cf367e306cda835af (MD5) Previous issue date: 2012 / Resumo: Devido ao aumento considerável de trabalhadores noturnos é importante o estudo dos efeitos deste tipo de trabalho na saúde do trabalhador. Estudos atuais demonstram que trabalhos em turno e noturno favorecem transtornos digestivos relacionados a diferenças no hábito alimentar, tanto no valor calórico total, como no horário e número de refeições. Além disso, há aumento dos fatores de risco cardiovasculares, tais como: altos níveis de triglicérides e colesterol séricos, obesidade abdominal, resistência à insulina e outros marcadores da síndrome metabólica. Estes fenômenos estão relacionados a um ganho e redistribuição do peso corporal, em parte atribuível a diferenças no padrão de fome e saciedade. Trabalhadores do turno noturno podem apresentar perturbação no ritmo biológico endógeno em função do conflito temporal entre o relógio biológico endógeno e a estrutura de funcionamento das atividades sociais. Esta dessincronização pode produzir transtornos intensos e persistentes na fisiologia do sono. Foram selecionados 12 trabalhadoras de turno noturno e 12 do diurno do HC-UNICAMP, com IMC entre 25 e 29.9 (sobrepeso). O objetivo deste trabalho foi comparar uma população trabalhadora de turno noturno com uma população trabalhadora diurna, em relação a componentes bioquímicos e antropométricos da síndrome metabólica. Além disso, a caracterização das respostas de hormônios reguladores da fome e saciedade foi acessada a partir de um teste de refeição padrão, com dosagens de grelina, (hormônio orexigênico), oxintomodulina, xenina, glucagon-like peptide 1 (GLP-1) e PYY3-36 (hormônios anorexigênicos). A resistência à insulina foi avaliada por índices que relacionam a produção de insulina com a curva glicêmica durante o teste de refeição (Metabolic Clearance Rate, ou índice de Stumvoll). Estes mesmos voluntários foram avaliados quanto à qualidade de sono, ao cronótipo e ao estado inflamatório sub-clínico (avaliado pelos níveis circulantes de interleucina 6, TNF-?, adiponectina e proteína C-reativa). Na avaliação quanto ao cronótipo, a maior proporção de indivíduos indiferentes foram encontrados no grupo do turno noturno. A qualidade de sono avaliada pelo score de Pittsburgh não demonstrou diferença significante entre os grupos estudados. Os trabalhadores de turno noturno demonstraram valores maiores para disfunção diurna, demonstrando sonolência excessiva diurna. O principal achado foi a caracterização de uma resposta de produção do hormônio orexigênico - grelina - aumentada no período pós-prandial das voluntárias de trabalho noturno e uma resposta reduzida de xenina (um hormônio anorexígeno e de fonte estomacal). Assim este fato pode ser responsável pela mudança do comportamento alimentar e consequente ganho de peso destas trabalhadoras de turno noturno. / Abstract: Due to the considerable increase of night shift workers it is important the study of its effects on worker health. Recent studies reveal that work in shifts and night shift work propitiate digestive disorders related to differences in dietary habits, in the total caloric content, as well as in the timing and number of meals. Moreover, it is noticed an increase in cardiovascular risk factors such as high levels of triglycerides and cholesterol, and abdominal obesity, insulin resistance and markers of metabolic syndrome. These phenomena are related to gain and redistribution of body weight, in part attributable to changes in the pattern of hunger and satiety. Night shift workers may have endogenous biological rhythm disturbance as a result of the temporal conflict between the endogenous biological clock and the functioning structure of social activities. This asynchronization may produce intense and persistent disorders in sleep physiology. We selected 12 night shift workers and 12 day workers of the HC-UNICAMP, with BMI between 25 and 29.9 (overweight). The objective of this study was to compare a population of night shift workers with a daytime working population in relation to anthropometric and biochemical components of the metabolic syndrome. Besides that, the characterization of the responses of hormones regulating hunger and satiety was accessed by means of a standard meal test , with dosages of ghrelin, oxyntomodulin, xenin, glucagon-like peptide 1 (GLP-1) and PYY3-36. Insulin resistance was evaluated by indexes relating the production of insulin during the glycemic test meal (Stumvol index). These same volunteers were evaluated for the quality of sleep, the chronotype and sub-clinical inflammatory state (assessed by circulating levels of interleukin-6, TNF-?, adiponectin and protein C-reactive). In the assessment for the chronotype, the highest proportion of indifferent individuals were found in the group of night shift. The quality of sleep assessed by pittsburgh score showed no significant difference between groups. The night shift workers showed higher values for daytime dysfunction, demonstrating excessive daytime sleepiness. The main finding was the characterization of a increased response in production of hormone - ghrelin - in the postprandial period of night shift workers and reduced response of xenina (an anorectic hormone source and stomach). As a conclusion, this fact may be responsible for the weight gain observed for those night shift workers. / Doutorado / Clinica Medica / Doutora em Clínica Médica

A manutenção da saúde, depende, dentre outros aspectos, do controle da massa corporal, uma vez que a obesidade está associada ao desenvolvimento de doenças crônicas. Sendo assim, o exercício pode ser considerado uma ferramenta eficaz nesse controle. Contudo, está evidenciado que o exercício realizado em alta intensidade pode ocasionar maior redução da gordura corporal. Dentre as hipóteses sugeridas para explicar tal fenômeno, a supressão do apetite pós-exercício foi levantada, no entanto, o efeito da intensidade sobre o apetite ainda é incipiente. Além disso, mulheres podem ter maior resposta compensatória que homens. Portanto, o objetivo do estudo foi comparar o efeito da intensidade no controle agudo do apetite, energia ingerida absoluta e relativa (energia ingerida menos o gasto calórico do exercício), percepção de fome e das concentrações sanguíneas de grelina acilada, peptídeo YY3-36, insulina, cortisol, glicose, ácidos graxos, colesterol e triacilglicerol em homens e mulheres. Para isso, 11 homens e 9 mulheres eutróficos, foram submetidos a 6 sessões, sendo a primeira destinada à determinação da potência aeróbia máxima (PAM) em cicloergômetro, e a segunda para realização do exercício intermitente de alta intensidade realizado na máxima intensidade (all out), composto por 60 x 8s:12s (EIAI-A), para determinação do trabalho total, o qual foi utilizado para equalização das demais sessões: a) EIAI-A; b) exercício intermitente de alta intensidade (EIAI) - 60s:60s a 100% da PAM; c) exercício contínuo de intensidade moderada (ECMI) a 60% da PAM; d) sessão controle (sem exercício). Cada visita teve duração de 4h, sendo que os participantes chegaram em jejum e receberam um café da manhã padrão. O exercício foi realizado 1,5h pós-café da manhã, e uma alimentação ad libitum foi servida 4h pós-café da manhã. Coletas de sangue e da percepção de fome (escala analógica visual) foram realizadas em jejum e em 2, 2,5, 3,25 e 4h de experimento e calculada a área sob a curva (ASC) para cada uma dessas variáveis. A comparação das variáveis sanguíneas e da percepção de fome foi feita através de análise de variância a três fatores (condição, sexo e momento), e das variáveis envolvendo a ASC e a energia ingerida foi conduzida através de análise a dois fatores (condição e sexo), seguida do pós-teste de Bonferroni se observada diferença significativa (P<0,05). Não houve diferença para a energia ingerida absoluta, porém, a energia ingerida relativa foi maior no controle quando comparada ao EIAI-A, EIAI, e ao ECMI, sem diferenças entre os tipos de exercício e sexos. A ASC da percepção de fome foi menor somente nos exercícios realizados em alta intensidade comparado com o controle, independentemente do sexo. O PYY3-36 foi inferior nas mulheres em relação aos homens ao passo que o cortisol foi inferior nos homens comparado com as mulheres. Houve interação entre situação e momento de coleta para o cortisol e insulina sendo os valores mais elevados no EIAI-A que no controle às 2,5 horas de experimento para o cortisol e às 3,25h para insulina. Portanto, embora não tenha havido diferença na energia ingerida relativa entre os tipos de exercícios, àqueles realizados em maior intensidade foram capazes de promover efeitos mais pronunciados na supressão do apetite, independentemente do sexo / Maintaining one\'s health depends, among other things, on controlling body weight, since obesity is associated with the development of chronic diseases. Accordingly, exercise is an effective tool in this control. It has been demonstrated that exercise performed at a high intensity can cause greater reduction in body fat. Among the hypotheses put forward of this phenomenon is the suppression of appetite. However, the understanding of the effect of the intensity on appetite is still incipient. In addition, women may have a greater compensatory response than men. Therefore, the aim of the study was to compare the effect of intensity on absolute and relative (energy intake less caloric expenditure of the exercise) energy intake, hunger and blood concentrations of acylated ghrelin, PYY3-36, insulin, cortisol, glucose, fatty acids, cholesterol and triacylglycerol in men and women. Accordingly, 11 men and 9 women, all eutrophic, underwent six sessions. The first was designed to determine their maximum aerobic power (MAP) on a cycle ergometer, and the second involved performing high-intensity intermittent exercise at maximum intensity (all out) for 60 x 8s: 12s (HIIE-A) in order to determine the total work, which was used for the equalization of the other sessions: a) HIIE-A; b) high intensity intermittent exercise (HIIE) - 60s: 60s at 100% of MAP; c) steady-state exercise (SSE) at 60% of the MAP; d) a control session. Each session lasted a total of 4 hours. The participants arrived in fasting and received a standard breakfast upon arrival. The exercise session was performed 1.5 h after breakfast, and an ad libitum meal was served 4 hours post-breakfast. Blood sample collection and perception of hunger were collected when fasting and at 2, 2.5, 3.25 and 4 hours into the experiment and the area under the curve (AUC) for each of these variables was calculated. A comparison of the blood sample variables and rating of hunger was performed by analyzing the variance of three factors (condition, sex, and time) and the analysis of the variables involving the AUC and energy intake was conducted through examination of two factors (sex and condition) followed by a Bonferroni post-test if significant differences (P<0.05) were observed. There was no difference for the absolute energy intake, however, relative energy intake was higher in the control compared to HIIE-A, HIIE, and SSE, with no differences between the types of exercise and sex. The AUC of hunger was lower in exercises performed at high intensity when compared to the control, regardless of sex. There was interaction between condition and time for cortisol and insulin, with higher levels in the HIIE-A than in the control at 2.5 hours for cortisol and 3.25 hours for insulin. Therefore, although there were no differences in energy intake relative to the types of exercises, those performed at a higher intensity promoted more pronounced effects on appetite suppression, regardless of sex

<p>Examining the effect of a modernized collaborative care intervention for depression consisting of both behavioral and pharmacologic treatments on 12-month change in individual somatic depressive symptoms (hyperphagia, poor appetite, hypersomnia, and disturbed sleep) and 12-month change in</p> <p>cardiometabolic biomarkers (HOMA-IR, BMI, hsCRP, leptin, and ghrelin). Further examining whether 12-month change in individual somatic depressive symptoms mediates the eIMPACT intervention’s effect on 12-month change in cardiometabolic biomarkers.</p>

Obesity is a worldwide problem affecting both children and adults. Genetic, physiological, environmental, psychological, social and economic factors interact in varying degrees, influencing body weight and fat distribution and the progress of obesity. Moreover, some anthropogenic chemicals have proven to be endocrine disrupting chemicals (EDCs) with the potential to interfere with different actions of hormones in the body. EDCs may thereby disrupt homeostasis, modifying developmental, behavioral and immune functions in humans and animals, and also promoting adiposity. Because hormones generally act at low concentrations, small changes in the endocrine system may lead to extensive effects. Based on data from experimental and epidemiological studies this thesis elucidates the relationship between a large number of environmental contaminants and obesity. The experimental studies demonstrated that fructose supplementation in the drinking water resulted in unfavorable metabolic alterations such as a higher liver somatic index (LSI), an increase in plasma triglycerides and increased plasma levels of apo A-I. Fructose in combination with exposure to bisphenol A (BPA) increased liver fat content and plasma levels of apo A-I in juvenile female Fischer 344 rats. The experimental studies also showed that the retro-peritoneal fat, which in rats is a distinct fat depot easy to distinguish and dissect, correlated well with the measurements of total fat mass analyzed with MRI, and could therefore be used as a substitute for total fat mass in rats. The epidemiological studies showed that circulating levels of persistent organic pollutants (POPs) were related to fat mass measured by DXA. OCDD, HCB, TNC, DDE and the less chlorinated PCBs were positively related to fat mass, while the more highly chlorinated PCBs showed a negative association. Further, circulating levels of BPA were positively associated with levels of the hormones adiponectin and leptin, but negatively related with ghrelin, hormones which are involved in the regulation of hunger and satiety. However, serum BPA levels were not related to measures of fat mass in the elderly individuals in the PIVUS cohort. This thesis concludes that environmental contaminants such as BPA and POPs most likely are contributors, along with genetic, social and behavioral factors, to the development of obesity.

Le récepteur X des farnésoïdes (FXR) fait partie de la superfamille des récepteurs nucléaires et agit comme un facteur de transcription suite à la liaison d’un ligand spécifique. Le récepteur FXR, activé par les acides biliaires, joue un rôle essentiel dans le métabolisme des lipides et du glucose en plus de réguler l’homéostasie des acides biliaires. Notre laboratoire a récemment mis en évidence une nouvelle voie de régulation du récepteur PPARγ en réponse au récepteur de la ghréline. En effet, la ghréline induit l’activation transcriptionnelle de PPARγ via une cascade de signalisation impliquant les kinases Erk1/2 et Akt, supportant un rôle périphérique de la ghréline dans les pathologies associées au syndrome métabolique. Il est de plus en plus reconnu que la cascade métabolique impliquant PPARγ fait également intervenir un autre récepteur nucléaire, FXR. Dans ce travail, nous montrons que la ghréline induit l’activation transcriptionnelle de FXR de manière dose-dépendante et induit également la phosphorylation du récepteur sur ses résidus sérine. En utilisant des constructions tronquées ABC et CDEF de FXR, nous avons démontré que la ghréline régule l’activité de FXR via les domaines d’activation AF-1 et AF-2. L’effet de la ghréline et du ligand sélectif GW4064 sur l’induction de FXR est additif. De plus, nous avons démontré que FXR est la cible d’une autre modification post-traductionnelle, soit la sumoylation. En effet, FXR est un substrat cellulaire des protéines SUMO-1 et SUMO-3 et la sumoylation du récepteur est ligand-indépendante. SUMO-1 et SUMO-3 induisent l’activation transcriptionnelle de FXR de façon dose-dépendante. Nos résultats indiquent que la lysine 122 est le site prédominant de sumoylation par SUMO-1, quoiqu’un mécanisme de coopération semble exister entre les différents sites de sumoylation de FXR. Avec son rôle émergeant dans plusieurs voies du métabolisme lipidique, l’identification de modulateurs de FXR s’avère être une approche fort prometteuse pour faire face à plusieurs pathologies associées au syndrome métabolique et au diabète de type 2. / The farnesoid X receptor (FXR) is a ligand-activated transcription factor within the nuclear receptor superfamily. FXR is activated by bile acids and plays a crucial role in the regulation of glucose and lipid metabolism and in bile acid homeostasis. Our group has recently identified the contribution of the ghrelin receptor in the regulation of the nuclear receptor PPARγ. Indeed, ghrelin triggers transcriptional activation of PPARγ through a concerted signaling cascade involving Erk1/2 and Akt kinases. These results support the peripheral actions of ghrelin in diseases associated with the metabolic syndrome. It is recognized that there is interplay between PPARγ metabolic cascade and FXR. Here, we demonstrate that ghrelin promotes FXR transcriptional activity in a dose-dependent manner and also promotes its phosphorylation on serine residues. By using truncated ABC and CDEF constructs of FXR, we found that ghrelin induces FXR activity through the AF-1 and AF-2 activation domains. The ghrelin-induced FXR activity is additive to the induction by the selective agonist GW4064. Also, we demonstrate that FXR is the target of sumoylation, another post-translational modification. In particular, FXR is modified by SUMO-1 and SUMO-3 in a ligand-independent manner. SUMO-1 and SUMO-3 promote dose-dependent transcriptional activity of FXR. Our results show that lysine 122 is the prevalent site of sumoylation by SUMO-1, though a compensation mechanism seems to exist between the various sumoylation sites of FXR. With its emerging role in several metabolic cascades, identification of FXR modulators represents a promising approach for the treatment of the metabolic syndrome and type 2 diabetes.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

INTRODUÇÃO: a ação dos hormônios contrarreguladores da insulina na cetoacidose diabética tem sido estudada desde a década 1970-80, e é sabido que seus níveis elevados, aumentando a resistência à insulina, têm papel importante na gênese da CAD. Leptina e ghrelina foram mais recentemente associadas à homeostase da glicose, no entanto, seu papel na CAD ainda é controverso. Os objetivos deste estudo foram: avaliar as alterações nas concentrações séricas de leptina e ghrelina presentes ao diagnóstico da CAD durante os primeiros três dias de seu tratamento e após a estabilização completa do quadro, as correlações com a insulina e outros contrarreguladores, comparando com indivíduos saudáveis. MÉTODOS: foram analisados 25 episódios de cetoacidose diabética em 22 pacientes admitidos no setor de emergência pediátrica de um hospital terciário em São Paulo, Brasil, entre março de 2010 e julho de 2013. Os episódios de cetoacidose foram manejados com reposição endovenosa de fluidos e eletrólitos e análogos de ação ultrarrápida de insulina subcutânea intermitente. Amostras para glicose, insulina, leptina, ghrelina, GH, cortisol e catecolaminas foram obtidas no momento da admissão (T0), durante o tratamento da cetoacidose (após 2, 4, 6, 12, 24 e 72 horas) e em um momento estável após a alta (TE). Os dados foram analisados utilizando-se os testes ANOVA ou Kruskal-Wallis para a comparação de variáveis contínuas durante o tratamento, Teste t de Student ou Mann Whitney para a comparação entre pacientes e grupo controle, e testes de Pearson ou Spearman para correlação entre as variáveis; p < 0.05 foi considerado significativo. RESULTADOS: observamos três fases distintas (a): o diagnóstico de CAD (T0) em que prevalecem hiperglicemia, insulinopenia e elevação de hormônios contrarreguladores; nesse momento, as concentrações de leptina foram menores que no grupo controle, provavelmente relacionadas à insuficiência de energia, estado hipercatabólico e elevação dos hormônios contrarreguladores; as concentrações de ghrelina foram menores que no grupo controle, apesar do hipercatabolismo, da hipoinsulinemia e da hiperglucagonemia, todas situações que fisiologicamente elevariam seus níveis, possivelmente devido à hiperglicemia marcante do momento; (b) durante o tratamento da CAD (T2 a T72): com redução gradual da glicemia até T24, elevação gradual da insulina, redução de glucagon, GH, cortisol e norepinefrina; nesse período, ocorreu elevação gradual da leptina após o início do tratamento com insulina, que atingiu níveis comparáveis ao GC no T72; redução da ghrelina (T4 menor que T72), provavelmente inibida pela hiperglicemia e por doses suprafisiológicas de insulina; e (c) após a resolução da CAD (TE): com hiperinsulinização; GH, cortisol e norepinefrina comparáveis ao GC, glucagon reduzido em relação ao GC, possivelmente supresso pelos altos níveis de insulina; as concentrações de leptina foram maiores que em T0 e comparáveis ao GC; os níveis de ghrelina, comparáveis ao diagnóstico e durante o tratamento da CAD, ainda significativamente menores que no GC, provavelmente influenciados pela hiperglicemia, hiperinsulinemia e baixos níveis de glucagon. CONCLUSÕES: as concentrações de leptina diminuídas ao diagnóstico de CAD tornam-se semelhantes em pacientes com DM1 estáveis em relação a indivíduos saudáveis, podendo ser um marcador de hipercatabolismo. As concentrações de ghrelina permaneceram baixas durante todo o estudo em pacientes diabéticos, independentemente da descompensação / INTRODUCTION: The role of glucoregulatory hormones in diabetic ketoacidosis have been investigated since 1970-80s and the elevation of growth hormone, cortisol and norepinephrine reduce the sensitivity to insulin. Leptin and Ghrelin have more recently been shown to regulate glucose and insulin metabolism; however, their functions in DKA are still controversial. The aims of this study were to analyze leptin, ghrelin and their relationships with other glucoregulatory hormones on diagnosis of diabetic ketoacidosis, during the first 72 hours of treatment and after recovery compared with healthy subjects. METHODS: We examined 25 DKA episodes in 22 patients who were admitted to the pediatric emergency department of a tertiary hospital in São Paulo, Brazil, from March 2010 to July 2013. These episodes were managed with fluids and electrolytes replacement and intermittent subcutaneous fast-acting insulin analogues. Samples for blood glucose, insulin, leptin, ghrelin, GH, cortisol, and catecholamines were obtained on admission (T0), during treatment (after 2, 4, 6, 12, 24 and 72 hours) and after discharge (TS). The control group (CG) was comprised by 21 healthy subjects, who submitted a single blood sample. Data were analyzed by ANOVA or Kruskal-Wallis to compare continuous variables during treatment, student t-test or Mann Whitney for comparisons between patients and controls, and Pearson or Spearman correlations between variables; p < 0.05 was considered to be significant. RESULTS: we observed three distinct phases: (a) on diagnosis of DKA (T0) where hyperglycemia, insulinopenia, and elevated glucoregulatory hormones prevail; leptin concentrations were lower than CG at this moment, probably related to energy insufficiency, hypercatabolic state, and elevated glucoregulatory hormones; ghrelin concentrations were lower than CG at this moment, despite hypercatabolism, hypoinsulinemia and hyperglucagonemia, situations that physiologically would increase them, possibly related to marked hyperglycemia at T0; (b) during DKA treatment (T2 to T72): with gradual reduction of blood glucose until T24, gradual rise of insulin; reduction of glucagon, GH, cortisol and norepinephrine. Leptin levels rises gradually after the start of insulin treatment and is comparable to control group at T72; reduction of ghrelin (T4 lower than T72), possibly inhibited by hyperglycemia and supraphysiological doses of insulin, all lower than CG; and (c) After DKA (TS), in an outpatient setting: with marked hyperinsulinization, GH, cortisol and norepinephrine were comparable to CG. Glucagon was lower than CG, possibly suppressed by high insulin levels; leptin was higher than T0 and comparable to CG; ghrelin levels were comparable to all samples during DKA treatment, and still significantly lower than CG, probably influenced by hyperglycemia, hyperinsulinemia and low glucagon levels. CONCLUSIONS: Low leptin levels were a marker of hypercatabolic state, with normalization of its concentrations with DKA resolution. Ghrelin was low in diabetic patients independent of metabolic derangements

O epitélio gástrico de ratos passa por modificações morfofisiológicas importantes durante o primeiro mês de vida pós-natal e a dieta é um dos principais fatores que influenciam esse desenvolvimento. Ratos receberam dieta com 20% (C) ou 8% (RP) de proteína, durante o período pré e pós-natal. Avaliamos em ratos de 14, 30 e 50 dias os efeitos da restrição protéica sobre proliferação celular no epitélio gástrico, massa do estômago e corpórea, comprimento do intestino e, expressão de ghrelina no estômago e no plasma. O grupo RP apresentou proliferação celular, massa do estômago e corpórea e comprimento do intestino reduzidos em relação ao grupo C. E maior imunomarcação para ghrelina em animais RP com 30 e 50d em comparação ao grupo C. Não houve diferença na imunomarcação entre animais de 14d. Os níveis plasmáticos de ghrelina apresentaram a mesma tendência observada na imunomarcação. O consumo de quantidade adequada de proteína é importante durante o desenvolvimento gástrico de ratos e a ghrelina apresenta resposta hormonal diferente de acordo com a idade do animal. / The gastric epithelium of rats undergoes morphophysiological changes throughout the first month of life and diet is one of the main factors influencing the development. Rats were fed a 20% (NP) or 8% (RP) protein diet throughout the pre- and post-natal life. We analyzed the cell proliferation and observed the body and stomach weight and small intestine length at 14, 30 and 50 days rats. Additionally, we evaluated ghrelin in gastric epithelium and its plasma levels. Cell proliferation in the gastric epithelium, body and stomach weight and small intestine length were reduced in RP animals when compared to NP animals. We observed an increase in the number of labeled cells for ghrelin in 30- and 50-d-old RP rats when compared to the NP group and no difference was found in 14-d-old animals. Plasma ghrelin levels showed the same results observed in immunohistochemical reactions. These results emphasize the importance of diet protein on the development of gastric mucosa and protein restriction seems to differently modulate ghrelin response at different ages.