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Obesity is a chronic low-grade inflammation condition related to cardiac disorders. However, the mechanism responsible for obesity-related cardiac inflammation is unclear. The toll-like receptor 4 (TLR-4) belongs to a receptor of the transmembrane family responsible for the immune response whose activation stimulates the production of proinflammatory cytokines.To test whether the activation of the TLR-4 receptor participates in the obesity cardiomyopathy process, due to cytokine production through NF-ĸB activation.Male Wistar rats were randomized into two groups: the control group (C, n= 8 animals) that received standard diet/water and the obese group (OB, n= 8 animals) that were fed a high sugar-fat diet and water plus 25% of sucrose for 30 weeks. Nutritional analysis: body weight, adiposity index, food, water, and caloric intake. Obesity-related disorders analysis: plasma glucose, uric acid and triglycerides, HOMA-IR, systolic blood pressure, TNF-α in adipose tissue. Cardiac analysis included: TLR-4 and NF-ĸB protein expression, TNF-α and IL-6 levels. Comparison by unpaired Student's t-test or Mann- Whitney test with a p-value0.05 as statistically significant.The OB group showed obesity, high glucose, triglycerides, uric acid, HOMA, systolic blood pressure, and TNF-α in adipose tissue. OB group presented cardiac remodeling and diastolic dysfunction. TLR-4 and NF-ĸB expression and cytokine levels were higher in OB.Our findings conclude that, in an obesogenic condition, the inflammation derived from cardiac TLR-4 activation can be a mechanism able to lead to remodeling and cardiac dysfunction.A obesidade é uma condição inflamatória crônica de baixo grau relacionada a distúrbios cardíacos. No entanto, o mecanismo responsável pela inflamação cardíaca relacionada à obesidade não é claro. O receptor do tipo toll 4 (TLR-4) pertence a um receptor da família das transmembranas, responsável pela resposta imune, cuja ativação estimula a produção de citocinas pró-inflamatórias.Testar se a ativação do receptor TLR-4 participa do processo de cardiomiopatia da obesidade, devido à produção de citocinas por meio da ativação do NF-ĸB.Ratos Wistar machos foram randomizados em dois grupos: o grupo controle (C, n = 8 animais) que recebeu dieta padrão/água e o grupo obeso (OB, n = 8 animais) que foi alimentado com dieta rica em açúcar e gordura e água mais 25% de sacarose por 30 semanas. Análise nutricional: peso corporal, índice de adiposidade, alimentos, água e ingestão calórica. Análise de distúrbios relacionados à obesidade: glicose plasmática, ácido úrico e triglicerídeos, HOMA-IR, pressão arterial sistólica, TNF-α no tecido adiposo. A análise cardíaca incluiu: expressão das proteínas TLR-4 e NF-ĸB, níveis de TNF-α e IL-6. Comparação pelo teste t de Student não pareado ou teste de Mann-Whitney com um valor de p0,05 como estatisticamente significativo.O grupo OB apresentou obesidade, glicose elevada, triglicerídeos, ácido úrico, HOMA, pressão arterial sistólica e TNF-α no tecido adiposo. O grupo OB apresentou remodelação cardíaca e disfunção diastólica. A expressão de TLR-4 e NF-ĸB e os níveis de citocinas foram maiores em OB.Nossos achados concluem que, em uma condição obesogênica, a inflamação derivada da ativação do TLR-4 cardíaco pode ser um mecanismo capaz de levar à remodelação e disfunção cardíaca.

White adipose tissue (WAT) is a highly adaptive endocrine organ that continuously remodels in response to nutritional cues. WAT expands to store excess energy by increasing adipocyte number and/or size. Failure in WAT expansion has serious consequences on metabolic health resulting in altered lipid, glucose, and inflammatory profiles. Besides an impaired adipogenesis, fibrosis and low-grade inflammation also characterize dysfunctional WAT. Nevertheless, the precise mechanisms leading to impaired WAT expansibility are yet unresolved. Autophagy is a conserved and essential process for cellular homeostasis, which constitutively allows the recycling of damaged or long-lived proteins and organelles, but is also highly induced under stress conditions to provide nutrients and remove pathogens. By modulating protein and organelle content, autophagy is also essential for cell remodeling, maintenance, and survival. In this line, autophagy has been involved in many processes affected during WAT maladaptation, including adipogenesis, adipocyte, and macrophage function, inflammatory response, and fibrosis. WAT autophagy dysregulation is related to obesity and diabetes. However, it remains unclear whether WAT autophagy alteration in obese and diabetic patients are the cause or the consequence of WAT malfunction. In this review, current data regarding these issues are discussed, focusing on evidence from human studies. Yes

Made available in DSpace on 2021-07-14T10:39:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-02-15. Added 1 bitstream(s) on 2021-07-14T11:35:03Z : No. of bitstreams: 1 S1807-86722018000100101.pdf: 1828430 bytes, checksum: 643aa17bc81e2b30a8f0e846937d3fa2 (MD5) Objetivou-se avaliar o efeito da temperatura no crescimento dos tecidos de tilápias do Nilo das linhagens Vermelha, GIFT e Supreme. Alevinos de aproximadamente 1,4 g, oriundos de populações de machos revertidos, foram mantidos em três sistemas de recirculação. Cada sistema contendo contém seis caixas d’água de 0,5 m³, em três temperaturas (22, 28 e 30ºC). Foram coletados dez peixes de cada tratamento. Os peixes foram insensibilizados, eutanasiados e pesados. Foram realizadas amostragens das regiões da musculatura dorsal, do pedúnculo caudal, do tecido adiposo subcutâneo ventral e visceral. Lâminas histológicas foram confeccionadas e avaliadas para determinar o diâmetro das células. O delineamento experimental foi inteiramente casualizado em esquema fatorial 3 X 3 (linhagem X temperatura). A análise de variância foi realizada e as médias foram comparadas. Maiores pesos foram encontrados para os peixes cultivados a 30ºC (56,23 g), quando comparados àqueles cultivados a 28 (42,12 g) ou 22ºC (10,52 g). A temperatura resfriada da água (22ºC) pode ter contribuído para a hipertrofia das fibras musculares brancas e dos adipócitos viscerais das tilápias, quando comparada a 28 ou 30ºC. As linhagens de tilápia Vermelha, GIFT e Supreme apresentam diferenças de crescimento do tecido muscular e adiposo em resposta à temperatura de cultivo. This study aimed to evaluate the effect of temperature on the tissue growth of Red, GIFT and Supreme tilapia strains. Fingerlings of approximately 1.4 g from male populations were reared for a period of 60 days, in three recirculating systems, each system containing 6 water tanks of 0.5 m³, at three temperatures (22, 28 and 30ºC). Ten fish of each recirculation system and each temperature studied were sampled. Fishes have been anesthetized, euthanized and weighed. The samplings have been done from the dorsal musculature, caudal, visceral and ventral subcutaneous adipose tissue. Histological sections were prepared and evaluated to determine the diameter of the cells. The experimental design was completely randomized factorial 3 X 3 (strain X temperature). Analysis of variance was performed and means were compared. Higher weights were found for fish reared at 30°C (56.23 g) compared to those grown at 28 (42.12 g) or 22°C (10.52 g). The cooled water temperature (22°C) may have contributed to the hypertrophy of white muscle fibers and visceral adipocytes from tilapia, compared to 28 or 30ºC. Red Tilapia, GIFT and Supreme strains show differences in muscle growth and adipose tissues in response to temperature of cultivation. Universidade Estadual Paulista ‘Júlio Mesquita Filho’, Centro de Aquicultura Agência Paulista de Tecnologia do Agronegócio Universidade do Oeste Paulista Universidade Estadual Paulista ‘Júlio Mesquita Filho’, Centro de Aquicultura

We investigate stratification patterns and topographical variations in the blubber of the striped dolphin (Stenella coeruleoalba) to gain insights into its regionally-specific functions. We collected blubber from 10 stranded striped dolphins (5 females and 5 males) from the eastern coast of Spain in 2007-2009, at 11 body positions. Histological measurements (adipocyte number and area) and blubber lipid content were analysed for each position. Histological measurements revealed stratification of blubber into outer, middle, and inner layers. Both the adipocyte number and area were largest in the middle layer. The adipocyte number was higher in the outer than the inner layer, whereas the adipocyte area was higher in the inner than the outer layer. The ventral anterior position did not follow this pattern, likely due to its proximity to the acoustic blubber, which is known to have a different biochemical composition. The stratification in morphological blubber characteristics most likely reflects functional differences. The outer layer may provide structural support and act as a mechanical barrier with a minor role in energy storage. The middle layer may be responsible for thermoregulation, and the inner layer could be responsible for energy mobilization, which is favoured by its proximity to the body core and a higher vascularization. In addition, an increasing gradient from dorsal to ventral positions was observed in the mean number of adipocytes and lipid content, with the exception of the caudal region. Although both ventral and dorsal blubber can have insulator and buoyancy functions, the ventral blubber may mainly serve as an energy reserve. En el presente estudio se investigaron los patrones de estratificación así como las variaciones topográficas en la grasa del delfín listado (Stenella coeruleoalba) con el fin de conocer mejor las posibles funciones regionales de este tejido. Se recolectaron muestras de grasa en 11 posiciones corporales diferentes de 10 delfines listados (5 hembras y 5 machos) varados en la costa este de España entre los años 2007 y 2009. Las medidas histológicas (número de adipocitos y área de los mismos) y el contenido lipídico se analizaron en cada una de las posiciones. Las medidas histológicas mostraron que la grasa se estratificaba en 3 capas: externa, media e interna. Tanto el número de adipocitos como su área eran mayores en la capa media. El número de adipocitos era superior en la capa externa que en la interna, mientras que el área de los adipocitos era mayor en la capa interna que en la externa. Sin embargo, la región ventral anterior no seguía este patrón, probablemente esto sea debido a que esta región se encuentra muy próxima a la grasa acústica, que es conocida por presentar una composición bioquímica diferente al resto de grasa corporal. La estratificación morfológica observada en la grasa probablemente esté reflejando una diferenciación funcional. La capa más externa podría dar soporte estructural y actuar como barrera mecánica, con un papel menos importante como almacén de reservas energéticas. La capa media podría ser responsable de la termorregulación, mientras que en la capa interna se produciría la movilización energética, lo cual se vería favorecido por su elevada vascularización y por estar en contacto con el interior del cuerpo. Además, se observó que tanto el número de adipocitos como el contenido lipídico seguían un gradiente creciente desde las posiciones dorsales a las ventrales, a excepción de la región caudal. Aunque tanto la grasa de la región dorsal como la de la ventral pueden presentar funciones de flotabilidad y aislamiento térmico, la grasa de la región ventral podría estar actuando principalmente como región de reserva energética.

Adipocyte dysfunction in obesity is commonly associated with impaired insulin signalling in adipocytes and insulin resistance. Insulin signalling has been associated with caveolae, which are coated by large complexes of caveolin and cavin proteins, along with proteins with membrane‐binding and remodelling properties. Here, we analysed the regulation and function of a component of caveolae involved in growth factor signalling in neuroendocrine cells, neuroendocrine long coiled‐coil protein‐2 (NECC2), in adipocytes. Studies in 3T3‐L1 cells showed that NECC2 expression increased during adipogenesis. Furthermore, NECC2 co‐immunoprecipitated with caveolin‐1 (CAV1) and exhibited a distribution pattern similar to that of the components of adipocyte caveolae, CAV1, Cavin1, the insulin receptor and cortical actin. Interestingly, NECC2 overexpression enhanced insulin‐activated Akt phosphorylation, whereas NECC2 downregulation impaired insulin‐induced phosphorylation of Akt and ERK2. Finally, an up‐regulation of NECC2 in subcutaneous and omental adipose tissue was found in association with human obesity and insulin resistance. This effect was also observed in 3T3‐L1 adipocytes exposed to hyperglycaemia/hyperinsulinemia. Overall, the present study identifies NECC2 as a component of adipocyte caveolae that is regulated in response to obesity and associated metabolic complications, and supports the contribution of this protein as a molecular scaffold modulating insulin signal transduction at these membrane microdomains., La disfunción de los adipocitos en la obesidad se asocia comúnmente con la alteración de la señalización de la insulina en los adipocitos y la resistencia a la insulina. La señalización de la insulina se ha asociado con las caveolas, que están recubiertas por grandes complejos de proteínas de caveolina y cavina, junto con proteínas con propiedades de remodelación y unión a la membrana. Aquí, analizamos la regulación y la función de un componente de las caveolas involucrado en la señalización del factor de crecimiento en las células neuroendocrinas, la proteína 2 neuroendocrina de espiral larga (NECC 2 ) , en los adipocitos. Los estudios en células 3T3‐L1 mostraron que la expresión de NECC 2 aumentó durante la adipogénesis. Además, NECC 2 co‐inmunoprecipitado con caveolina‐1 ( CAV1) y mostró un patrón de distribución similar al de los componentes de las caveolas adipocitarias, CAV 1, Cavin1, el receptor de insulina y la actina cortical. Curiosamente, la sobreexpresión de NECC 2 mejoró la fosforilación de Akt activada por insulina, mientras que la regulación negativa de NECC 2 perjudicó la fosforilación de Akt y ERK 2 inducida por insulina . resistencia a la insulina. Este efecto también se observó en adipocitos 3T3‐L1 expuestos a hiperglucemia/hiperinsulinemia. En general, el presente estudio identifica NECC2 como un componente de las caveolas de los adipocitos que se regula en respuesta a la obesidad y las complicaciones metabólicas asociadas, y respalda la contribución de esta proteína como un andamio molecular que modula la transducción de señales de insulina en estos microdominios de membrana.

Obesity is characterized by an excessive increase in the adipose tissue mass, and is associated with higher incidence of several chronic metabolic diseases, such as type 2 diabetes. Therefore, its increasing prevalence is a public health concern, and it is important to better understand its etiology to develop new therapeutic strategies. Evidence accumulated over the years indicates that obesity is associated with a marked activation in adipose tissue of the mechanistic target of rapamycin complex 1 (mTORC1), a signaling pathway that controls lipid metabolism, and adipocyte formation and maintenance. Curiously, mTORC1 is also involved in the control of nonshivering thermogenesis and recruitment as well as browning of white adipose tissue. In this review, we explored mTORC1 functions in adipocytes and presented evidence, suggesting that mTORC1 may either increase or reduce adiposity, depending on the conditions and activation levels. RESUMO A obesidade é caracterizada pelo aumento excessivo da massa de tecido adiposo, estando associada à maior incidência de diversas doenças metabólicas crônicas, como diabetes tipo 2. Sua crescente prevalência é uma questão de saúde pública, e faz-se importante compreender melhor sua etiologia, para desenvolver novas estratégias terapêuticas. As evidências acumuladas por muitos anos indicam que a obesidade está associada à significativa ativação no tecido adiposo do complexo 1 da proteína alvo mecanístico da rapamicina (mTORC1), uma via de sinalização que regula o metabolismo de lipídeos, bem como a formação e manutenção de adipócitos. Curiosamente, mTORC1 também está envolvido no controle da termogênese, independente do tremor muscular, e no recrutamento e browning de tecido adiposo branco. Nesta revisão, exploramos as diferentes funções do mTORC1 em adipócitos e apresentamos evidências que sugerem que o mTORC1 pode aumentar ou reduzir a adiposidade, dependendo das condições e de seu nível de ativação.

Real-time or quantitative PCR (qPCR) is a useful technique that requires reliable reference genes for data normalization in gene expression analysis. Adipogenesis is among the biological processes suitable for this technique. The selection of adequate reference genes is essential for qPCR gene expression analysis of human Vascular Stromal Cells (hVSCs) during their differentiation into adipocytes. To the best of our knowledge, there are no studies validating reference genes for the analyses of visceral and subcutaneous adipose tissue hVSCs from subjects with different Body Mass Index (BMI) and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) index. The present study was undertaken to analyze this question. We first analyzed the stability of expression of five potential reference genes: CYC, GAPDH, RPL13A, EEF1A1, and 18S ribosomal RNA, during in vitro adipogenic differentiation, in samples from these types of patients. The expression of RPL13A and EEF1A1 was not affected by differentiation, thus being these genes the most stable candidates, while CYC, GAPDH, and 18S were not suitable for this sort of analysis. This work highlights that RPL13A and EEF1A1 are good candidates as reference genes for qPCR analysis of hVSCs differentiation into adipocytes from subjects with different BMI and HOMA-IR. Instituto de Salud Carlos III (PI10/01947, PI13/02628) with Fondos FEDER and the Consejería de Economía e Innovación, Ciencia y Empleo, Junta de Andalucía (CTS-7895) with Fondos FEDER. R. El Bekay is under a contract Miguel Servet type II (CPII13/00041) from the Instituto de Salud Carlos III. F-JB-S is a recipient of a "Miguel Servet II" research contract (CPII13/00042) and also belongs to the regional "Nicolás Monardes" research program of the Consejería de Salud (C-0070-2012; Junta de Andalucía, Spain). This work was supported by the FIS-Thematic Networks and Co-Operative Research Centres RIRAAF (RD07-0064). JM is under the Programa de Intensificación de la Actividad Investigadora del Sistema Nacional de Salud. AV-R is under a contract Proyectos de I+D+i para jóvenes investigadores from the Ministerio de Economía y Competitividad (SAF2014-60649-JIN). S-YR-Z is recipient of a post-doctoral contract from Consejería de Salud de la Junta de Andalucía (RH-0070-2013).

Molecules of animal or bacterial origin, which pose a risk for zoonoses or immune rejection, are commonly used for extraction, culture, and cryopreservation of mesenchymal stem cells. There is no sequential and orderly protocol for producing human adipose-derived stem cells (hASCs) under xeno-free conditions. After standardizing a human platelet lysate (hPL) production protocol, four human adipose tissue samples were processed through explants with fetal bovine serum (FBS)-supplemented or hPL-supplemented media for extracting the adipose-derived stem cells. The cells were cultivated in cell culture medium + hPL (5%) or FBS (10%). The cellular replication rate, immunophenotype, and differentiation potential were evaluated at fourth passage. Cellular viability was evaluated before and after cryopreservation of the cells, with an hPL-based solution compared with an FBS-based solution. The explants cultured in hPL-supplemented media showed earlier and faster hASC proliferation than did those supplemented with FBS. Likewise, cells grown in hPL-supplemented media showed a greater proliferation rate, without losing the immunophenotype. Osteogenic differentiation of xeno-free hASC was higher than the hASC produced in standard conditions. However, adipogenic differentiation was reduced in xeno-free hASC. Finally, the cells cryopreserved in an hPL-based solution showed a higher cellular viability than the cells cryopreserved in an FBS-based. In conclusion, we have developed a complete xeno-free protocol for extracting, culturing, and cryopreserving hASCs that can be safely implemented in clinical studies. Significance This study was performed to standardize a complete ordered protocol to produce xeno-free human adipose-derived mesenchymal stem cells (hASCs) as a safe therapeutic alternative. Cells were extracted by adipose tissue explants and then cultured and cryopreserved using human platelet lysate (hPL). Different scientific journals have published data regarding the use of hPL as a safe fetal bovine serum substitute for hASC culture, using heparin to avoid clot formation. This article reports the use of hPL for extracting, culturing, and cryopreserving hASCs without anticoagulant.

Introduction: Tendinopathies and tendon tears account for over 30% of all musculoskeletal consultations. Obesity, which is becoming one of the world´s most prevalent public health issues, may be associated with this condition. Objective: To review the literature about tendinopathies and obesity association. Methods: This is a descriptive exploratory study using the portal Medline. Literature in English language from 2006 to 2014 were reviewed. Results: The pathogenesis of tendinopathies includes inflammatory, regenerative and degenerative processes that happen simultaneously from early to late phases of the disease. Mechanical stress upon tendons seems to be one of the most important factors to initiate the inflammatory response, but it´s not the only one that can deflagrate it: there are other extrinsic, genetic and metabolic factors that may be involved. Therefore, tendinopathies in obese patients can be due to tendon overload because of the excess of weight, but also because of increased production of pro-inflammatory mediators related to fat tissue such as adipokines. This pro-inflammatory state that obese people can suffer is known as adiposopathy, or sick fat syndrome. Weight loss is associated with decrease in adipokines and improvement of musculoskeletal symptoms. Conclusion: The relation of obesity and tendinopathies is supported by evidences of recent studies, exemplified in this review of literature. RESUMO Introdução: As tendinopatias e as fissuras em tendões respondem por 30% de todas as consultas médicas. A obesidade, que está se tornando um dos problemas de saúde pública mais prevalentes no mundo, pode estar associada com esta condição. Objetivo Revisar a literatura acerca da associação entre obesidade e tendinopatias. Métodos: Este é um estudo exploratório e descritivo utilizando artigos em língua inglesa do portal médico Medline, do período de 2006 a 2014. Resultados: Na patogênese das tendinopatias incluem-se elementos inflamatórios, regenerativos e degenerativos que aparecem de maneira simultânea em todos os estágios da doença. O estresse mecânico sobre os tendões parece ser um dos mais importantes na promoção do processo inflamatório inicial. Todavia não é o único. Existem fatores ambientais, genéticos e metabólicos atuando de maneira ativa. Portanto, as tendinopatias em indivíduos obesos podem se dever à sobrecarga mecânica pelo excesso de peso, mas, também, pelo aumento na produção de mediadores pró-inflamatórios relacionados ao tecido adiposo, como as adipocinas. O estado pró-inflamatório existente no indivíduo obeso é conhecido como adiposopatia ou síndrome da "gordura doente". A perda de peso está associada com decréscimo das adipocinas e diminuição da sintomatologia musculoesquelética. Conclusão: A associação da obesidade com tendinopatias tem sido fundamentada em estudos recentes como os desta revisão de literatura.

Objective Glycogen metabolism has emerged as a mediator in the control of energy homeostasis and studies in murine models reveal that adipose tissue might contain glycogen stores. Here we investigated the physio(patho)logical role of glycogen in human adipose tissue in the context of obesity and insulin resistance. Methods We studied glucose metabolic flux of hypoxic human adipoctyes by nuclear magnetic resonance and mass spectrometry-based metabolic approaches. Glycogen synthesis and glycogen content in response to hypoxia was analyzed in human adipocytes and macrophages. To explore the metabolic effects of enforced glycogen deposition in adipocytes and macrophages, we overexpressed PTG, the only glycogen-associated regulatory subunit (PP1-GTS) reported in murine adipocytes. Adipose tissue gene expression analysis was performed on wild type and homozygous PTG KO male mice. Finally, glycogen metabolism gene expression and glycogen accumulation was analyzed in adipose tissue, mature adipocytes and resident macrophages from lean and obese subjects with different degrees of insulin resistance in 2 independent cohorts. Results We show that hypoxia modulates glucose metabolic flux in human adipocytes and macrophages and promotes glycogenesis. Enforced glycogen deposition by overexpression of PTG re-orients adipocyte secretion to a pro-inflammatory response linked to insulin resistance and monocyte/lymphocyte migration. Furthermore, glycogen accumulation is associated with inhibition of mTORC1 signaling and increased basal autophagy flux, correlating with greater leptin release in glycogen-loaded adipocytes. PTG-KO mice have reduced expression of key inflammatory genes in adipose tissue and PTG overexpression in M0 macrophages induces a pro-inflammatory and glycolytic M1 phenotype. Increased glycogen synthase expression correlates with glycogen deposition in subcutaneous adipose tissue of obese patients. Glycogen content in subcutaneous mature adipocytes is associated with BMI and leptin expression. Conclusion Our data establish glycogen mishandling in adipose tissue as a potential key feature of inflammatory-related metabolic stress in human obesity., Highlights • Hypoxia redirects extracellular glucose to glycogen synthesis in human adipocytes. • Glycogen modifies the endocrine function of adipocytes and induces insulin resistance. • Glycogen stimulates leptin secretion through an autophagy-dependent mechanism. • Enforced glycogen accumulation in macrophages promotes M1 polarization. • Obesity is associated with higher GS expression and glycogen stores in adipose tissue.

We investigate stratification patterns and topographical variations in the blubber of the striped dolphin (Stenella coeruleoalba) to gain insights into its regionally-specific functions. We collected blubber from 10 stranded striped dolphins (5 females and 5 males) from the eastern coast of Spain in 2007-2009, at 11 body positions. Histological measurements (adipocyte number and area) and blubber lipid content were analysed for each position. Histological measurements revealed stratification of blubber into outer, middle, and inner layers. Both the adipocyte number and area were largest in the middle layer. The adipocyte number was higher in the outer than the inner layer, whereas the adipocyte area was higher in the inner than the outer layer. The ventral anterior position did not follow this pattern, likely due to its proximity to the acoustic blubber, which is known to have a different biochemical composition. The stratification in morphological blubber characteristics most likely reflects functional differences. The outer layer may provide structural support and act as a mechanical barrier with a minor role in energy storage. The middle layer may be responsible for thermoregulation, and the inner layer could be responsible for energy mobilization, which is favoured by its proximity to the body core and a higher vascularization. In addition, an increasing gradient from dorsal to ventral positions was observed in the mean number of adipocytes and lipid content, with the exception of the caudal region. Although both ventral and dorsal blubber can have insulator and buoyancy functions, the ventral blubber may mainly serve as an energy reserve., En el presente estudio se investigaron los patrones de estratificación así como las variaciones topográficas en la grasa del delfín listado (Stenella coeruleoalba) con el fin de conocer mejor las posibles funciones regionales de este tejido. Se recolectaron muestras de grasa en 11 posiciones corporales diferentes de 10 delfines listados (5 hembras y 5 machos) varados en la costa este de España entre los años 2007 y 2009. Las medidas histológicas (número de adipocitos y área de los mismos) y el contenido lipídico se analizaron en cada una de las posiciones. Las medidas histológicas mostraron que la grasa se estratificaba en 3 capas: externa, media e interna. Tanto el número de adipocitos como su área eran mayores en la capa media. El número de adipocitos era superior en la capa externa que en la interna, mientras que el área de los adipocitos era mayor en la capa interna que en la externa. Sin embargo, la región ventral anterior no seguía este patrón, probablemente esto sea debido a que esta región se encuentra muy próxima a la grasa acústica, que es conocida por presentar una composición bioquímica diferente al resto de grasa corporal. La estratificación morfológica observada en la grasa probablemente esté reflejando una diferenciación funcional. La capa más externa podría dar soporte estructural y actuar como barrera mecánica, con un papel menos importante como almacén de reservas energéticas. La capa media podría ser responsable de la termorregulación, mientras que en la capa interna se produciría la movilización energética, lo cual se vería favorecido por su elevada vascularización y por estar en contacto con el interior del cuerpo. Además, se observó que tanto el número de adipocitos como el contenido lipídico seguían un gradiente creciente desde las posiciones dorsales a las ventrales, a excepción de la región caudal. Aunque tanto la grasa de la región dorsal como la de la ventral pueden presentar funciones de flotabilidad y aislamiento térmico, la grasa de la región ventral podría estar actuando principalmente como región de reserva energética.

Journal Article; Research Support, Non-U.S. Gov't; Review; Obesity is considered a major health problem. However, mechanisms involved and its comorbidities are not elucidated. Recent theories concerning the causes of obesity have focused on a limit to the functional capacity of adipose tissue, comparing it with other vital organs. This assumption has been the central point of interest in our laboratory. We proposed that the failure of adipose tissue is initiated by the difficulty of this tissue to increase its cellularity due to excess in fat contribution, owing to genetic or environmental factors. Nevertheless, why the adipose tissue reduces its capacity to make new adipocytes via mesenchymal cells of the stroma has not yet been elucidated. Thus, we suggest that this tissue ceases fulfilling its main function, the storage of excess fat, thereby affecting some of the key factors involved in lipogenesis, some of which are reviewed in this paper (PPARγ, ROR1, FASN, SCD1, Rab18, BrCa1, ZAG, and FABP4). On the other hand, mechanisms involved in adipose tissue expandability are also impaired, predominating hypertrophy via an increase in apoptosis and a decrease in adipogenesis and angiogenesis. However, adipose tissue failure is only part of this great orchestra, only a chapter of this nightmare. Yes

Background/objectivesObesity has been linked to morbidity and mortality through increased risk for many chronic diseases. Endothelin (EDN) system has been related to endothelial function but it can be involved in lipid metabolism regulation: Receptor type A (EDNRA) activates lipolysis in adipocytes, the two endothelin receptors mediate arsenic-stimulated adipocyte dysfunction, and endothelin system can regulate adiposity by modulating adiponectin activity in different situations and, therefore, influence obesity development. The aim of the present study was to analyze if single nucleotide polymorphisms (SNPs) in the EDN system could be associated with human obesity.Subjects/methodsWe analyzed two samples of general-population-based studies from two different regions of Spain: the VALCAR Study, 468 subjects from the area of Valencia, and the Hortega Study, 1502 subjects from the area of Valladolid. Eighteen SNPs throughout five genes were analyzed using SNPlex.ResultsWe found associations for two polymorphisms of the EDNRB gene which codifies for EDN receptor type B. Genotypes AG and AA of the rs5351 were associated with a lower risk for obesity in the VALCAR sample (p=0.048, OR=0.63) and in the Hortega sample (p=0.001, OR=0.62). Moreover, in the rs3759475 polymorphism, genotypes CT and TT were also associated with lower risk for obesity in the Hortega sample (p=0.0037, OR=0.66) and in the VALCAR sample we found the same tendency (p=0.12, OR=0.70). Furthermore, upon studying the pooled population, we found a stronger association with obesity (p=0.0001, OR=0.61 and p=0.0008, OR=0.66 for rs5351 and rs3759475, respectively). Regarding plasma arsenic levels, we have found a positive association for the two SNPs studied with obesity risk in individuals with higher arsenic levels in plasma: rs5351 (p=0.0054, OR=0.51) and rs3759475 (p=0.009, OR=0.53).ConclusionsOur results support the hypothesis that polymorphisms of the EDNRB gene may influence the susceptibility to obesity and can interact with plasma arsenic levels.

Objective The present study aimed to examine the effects of thyroid hormone (TH), more precisely triiodothyronine (T3), on the modulation of TH receptor alpha (TRα) mRNA expression and the involvement of the phosphatidyl inositol 3 kinase (PI3K) signaling pathway in adipocytes, 3T3-L1, cell culture. Materials and methods: It was examined the involvement of PI3K pathway in mediating T3 effects by treating 3T3-L1 adipocytes with physiological (P=10nM) or supraphysiological (SI =100 nM) T3 doses during one hour (short time), in the absence or the presence of PI3K inhibitor (LY294002). The absence of any treatment was considered the control group (C). RT-qPCR was used for mRNA expression analyzes. For data analyzes ANOVA complemented with Tukey’s test was used at 5% significance level. Results T3 increased TRα mRNA expression in P (1.91±0.13, p0.001) and SI (0.99±0.15, p>0.001), induced by T3. Conclusion These results demonstrate that the activation of the PI3K signaling pathway has a role in T3-mediated indirect TRα gene expression in 3T3-L1 adipocytes. Objetivo O objetivo do presente estudo foi analisar os efeitos do hormônio tireoidiano (HT), triiodotironina (T3), na modulação da expressão de mRNA do receptor alfa (TRα) de HT e o envolvimento da via de sinalização da via fosfatidilinositol 3-quinase (PI3K) em adipócitos, 3T3-L1. Materiais e métodos: Foi examinado o envolvimento da via PI3K nos efeitos do T3 nos tratamentos de adipócitos, 3T3-L1, nas doses fisiológica (P=10nM) ou suprafisiológica (SI =100 nM) durante uma hora (tempo curto), na ausência ou na presença do inibidor da PI3K (LY294002). A ausência de qualquer tratamento foi considerada o grupo controle (C). RT-qPCR foi utilizado para analisar a expressão do mRNA. Para as análises dos dados, utilizou-se ANOVA complementada com o teste de Tukey a 5% de significância. Resultados O T3 aumentou a expressão de mRNA de TRα em P (1,91±0,13, p0,001) e SI (0,99±0,15, p>0,001), induzidos pelo T3. Conclusão Esses resultados demonstram que a ativação da via de sinalização de PI3K tem um papel importante na expressão do gene TRα mediada indiretamente pelo T3, em adipócitos 3T3-L1.

Context: Glucose-dependent insulinotropic peptide (GIP) has a central role in glucose homeostasis through its amplification of insulin secretion; however, its physiological role in adipose tissue is unclear. Objective: Our objective was to define the function of GIP in human adipose tissue in relation to obesity and insulin resistance. Design: GIP receptor (GIPR) expression was analyzed in human sc adipose tissue (SAT) and visceral adipose (VAT) from lean and obese subjects in 3 independent cohorts. GIPR expression was associated with anthropometric and biochemical variables. GIP responsiveness on insulin sensitivity was analyzed in human adipocyte cell lines in normoxic and hypoxic environments as well as in adipose-derived stem cells obtained from lean and obese patients. Results: GIPR expression was downregulated in SAT from obese patients and correlated negatively with body mass index, waist circumference, systolic blood pressure, and glucose and triglyceride levels. Furthermore, homeostasis model assessment of insulin resistance, glucose, and G protein-coupled receptor kinase 2 (GRK2) emerged as variables strongly associated with GIPR expression in SAT. Glucose uptake studies and insulin signaling in human adipocytes revealed GIP as an insulin-sensitizer incretin. Immunoprecipitation experiments suggested that GIP promotes the interaction of GRK2 with GIPR and decreases the association of GRK2 to insulin receptor substrate 1. These effects of GIP observed under normoxia were lost in human fat cells cultured in hypoxia. In support of this, GIP increased insulin sensitivity in human adipose-derived stem cells from lean patients. GIP also induced GIPR expression, which was concomitant with a downregulation of the incretin-degrading enzyme dipeptidyl peptidase 4. None of the physiological effects of GIP were detected in human fat cells obtained from an obese environment with reduced levels of GIPR. Conclusions: GIP/GIPR signaling is disrupted in insulin-resistant states, such as obesity, and normalizing this function might represent a potential therapy in the treatment of obesity-associated metabolic disorders.

Dissertação de Mestrado em Bioquímica, apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de Coimbra. Obesity is a pandemic public health problem, associated with a multitude of health problems such as cardiovascular disease, type 2 diabetes mellitus and other metabolic disorders. Considering the limited efficacy of current therapies to counteract the metabolic changes of obesity, new effective therapeutic strategies to increase energy expenditure and weight loss are under investigation. Bile acids and its antiobesogenic effects have been recently associated with an increased number of multilocular UCP-1-positive fat cells in white adipose tissue depots. These cells, also known as brite or beige cells, induce a conversion of white adipocytes with typical fatty acid storage towards an oxidative phenotype, thereby stimulating energy metabolic fluxes and improving whole-body metabolism. However, the mechanism underlying bile acid metabolic effects are still unclear. In fact, it remains to be established whether they are the result of a direct action on the adipose tissue or a consequence of actions in other key metabolic organs such as liver. Due to the critical role of the Wnt/ β-catenin signaling pathway in adipogenesis and its protective effect against obesity and associated metabolic alterations, we proposed to address: if the bile acid chenodeoxycholic acid (CDCA) is able to decrease fat accumulation in 3T3-L1 adipocyte cultures; if these effects are dependent on UCP-1 increased mitochondrial oxidative capacity and the implication of the Wnt/ β-catenin signaling pathway. CDCA exposure during 96 h induced a concentration-dependent decrease in triglycerides accumulation in adipocytes, being this effect blocked when the Wnt/ β-catenin pathway was inhibited. The reduction on lipid accumulation caused by CDCA was associated with an increase in UCP-1 content, and consequent mitochondrial uncoupling. In the presence of XAV939, a blocker of the Wnt/ β-catenin pathway, CDCA was not able to decrease triglyceride accumulation neither to induce an increase in UCP-1 content. Despite UCP-1 induction, CDCA treatment did not increase the content in electron transport chain proteins neither reactive oxygen species generation; mitochondrial membrane potential was increased in cells incubated with 50 μM CDCA. Importantly, our results showed for the first time that CDCA decreases lipid accumulation in vitro, an effect associated with increased UCP-1 content and involving the Wnt/β-catenin pathway. This favours the argument that CDCA action as general metabolic integrator is probably dependent on a direct effect on adipose tissue. A obesidade é uma pandemia deste século, sendo um problema de saúde pública que está associado a outras doenças tais como doenças cardiovasculares, diabetes mellitus tipo 2 e outras doenças metabólicas. Considerando a limitada eficácia das atuais terapias no tratamento das alterações metabólicas associadas à obesidade, novas estratégias terapêuticas efetivas direcionadas para o aumento do gasto energético e perda de peso têm sido alvo de investigação. Os ácidos biliares e os seus efeitos anti-obesogénicos têm sido recentemente associados ao aumento de adipócitos multiloculares com expressão de UCP-1 em depósitos de tecido adiposo. Estas células, também conhecidas por células “brite” ou “beige”, induzem a conversão de adipócitos do tecido adiposo branco tipicamente com função de armazenar ácidos gordos em células com um fenótipo mais oxidativo. Esta conversão induz a estimulação dos fluxos metabólicos energéticos, conduzindo a uma melhoria do metabolismo de todo o organismo. No entanto, o mecanismo subjacente à ação dos ácidos biliares na indução destes efeitos não é ainda conhecido. Na realidade, está ainda por esclarecer se os efeitos dos ácidos biliares se devem a um efeito directo no tecido adiposo ou se por outro lado, são consequência da acção dos ácidos biliares em orgãos chave no metabolismo, tal como o fígado. Dado o papel que a via de sinalização Wnt/ β-catenina tem na adipogénese, assim como os seus efeitos protectores contra a obesidade e alterações metabólicas associdas, propomo-nos a perceber: se o ácido biliar, ácido quenodeoxicólico (CDCA), induz uma diminuição da acumulação de triglicerídeos em culturas de adipócitos 3T3-L1; se os efeitos do CDCA são dependentes de um aumento da capacidade oxidativa mitocondrial associada à UCP-1 e qual a implicação da via da sinalização Wnt/ β-catenina nestes efeitos. A exposição ao CDCA durante 96 horas induziu uma diminuição na acumulação de triglicerídeos nos adipócitos, sendo este efeito dependente da concentração de CDCA e bloqueado quando a via Wnt/ β-catenina foi inibida. A redução na acumulação de triglicerídeos induzida pelo CDCA esteve associada com um aumento do conteúdo em UCP-1, e um consequente desacoplamento mitocondrial. Na presença do XAV939, um inhibidor da via Wnt/ β-catenina, o CDCA não induziu uma diminuição da acumulação de triglicerídeos, nem um aumento do conteúdo em UCP-1. A exposição de 3T3-L1 a CDCA não alterou o conteúdo em proteínas da cadeia transportadora nem a produção de ROS; o potencial de membrana mitocondrial foi mais elevado em células incubadas com 50 μM CDCA. Os nossos resultados mostraram pela primeira vez que o CDCA diminui a acumulação lipídica in vitro, estando este efeito associado a um aumento do conteúdo em UCP-1 e dependente da via da Wnt/ β-catenina. Assim, este estudo suporta o potencial efeito do CDCA como integrador metabólico, provavelmente através de um efeito direto no tecido adiposo.

The objective of this study was to evaluate the influence of integral and decaffeinated coffee brews (Coffea arabica L and C. canephora Pierre) on the metabolic parameters of rats fed with hyperlipidemic diet. Thirty male Wistar rats (initial weight of 270 g ± 20 g) were used in the study, which were divided into six groups five each. The treatments were normal diet, hyperlipidemic diet, hyperlipidemic diet associated with integral coffee arabica or canephora brews (7.2 mL/kg/day) and hyperlipidemic diet associated to decaffeinated arabica, or canephora brews, using the same dosage. After 41 days, performance analyses were conducted.The rats were then euthanized and the carcasses were used for the analysis of dried ether extract and crude protein. Fractions of adipose tissue were processed for histological analysis. There was a reduction in weight gain and accumulation of lipids in the carcasses, lower diameter of adipocytes and a lower relative weight of the liver and kidneys of rats fed with hyperlipidemic diet associated with integral coffee brew. Integral coffee brew reduced the obesity in the rats receiving hyperlipidemic diet, but the same effect did not occur with the decaffeinated types.

Made available in DSpace on 2016-04-01T18:44:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2013. Added 1 bitstream(s) on 2016-04-01T18:49:52Z : No. of bitstreams: 1 ISSN0004-2730-2013-57-05-368-374.pdf: 218443 bytes, checksum: 5474d376f1638e12ee42afe0365fd7b3 (MD5) Objetivo: Examinar o efeito de diferentes doses de triiodotironina (T3) sobre a expressão gênica dos receptores TRα e TRβ em diferentes tempos. Materiais e métodos: Adipócitos, 3T3-L1, foram incubados com T3 nas doses fisiológica (F, 10nM) e suprafisiológicas (SI, 100nM ou SII, 1000nM) ou veículo (controle, C) durante 0,5, 1, 6 ou 24h. mRNA dos TRs foram detectados utilizando PCR em tempo real. Resultados: Níveis de TRβ aumentaram em F em 0,5h. Após 1h, níveis de TRα aumentaram em F e SI comparado ao C, enquanto TRβ diminuiu no SII comparado com C, F, e SI. Após 6h, ambos os genes foram suprimidos em todas concentrações. Em 24h, níveis de TRα e TRβ retornaram aos do C. Conclusões: Ação do T3 em F iniciou-se em 1h para TRα e 0,5h para TRβ. Esses resultados são importantes para determinar tempo inicial e dose de T3 em que os receptores de HT são ativados em adipócitos. Objective: To examine the effect of different doses of triiodothyronine (T3) on mRNA levels of thyroid hormone receptors, TRα and TRβ, at different times. Materials and methods: 3T3-L1 adipocytes were incubated with T3 (physiological dose: F; supraphysiological doses: SI or SII), or without T3 (control, C) for 0.5, 1, 6, or 24h. TRα and TRβ mRNA was detected using real-time polymerase chain reaction. Results: F increased TRβ mRNA levels at 0.5h. After 1h, TRα levels increased with F and SI and TRβ levels decreased with SII compared with C, F, and SI. After 6h, both genes were suppressed at all concentrations. In 24h, TRα and TRβ levels were similar to those of C group. Conclusions: T3 action with F began at 1h for TRα and at 0.5h for TRβ. These results suggest the importance of knowing the times and doses that activate T3 receptors in adipocytes. Department of Physiology, São Paulo Federal University (Unifesp), São Paulo, SP, Brazil Department of Internal Clinic, Botucatu Medicine School, São Paulo State University (Unesp), Botucatu, SP, Brazil Department of Biostatistics, Biosciences Institute, Unesp, Botucatu, SP, Brazil

This is an open-access article distributed under the terms of the Creative Commons Attribution License.-- et al., [Context]: Expression and activity of the main lipogenic enzymes is paradoxically decreased in obesity, but the mechanisms behind these findings are poorly known. Breast Cancer 1 (BrCa1) interacts with acetyl-CoA carboxylase (ACC) reducing the rate of fatty acid biosynthesis. In this study, we aimed to evaluate BrCa1 in human adipose tissue according to obesity and insulin resistance, and in vitro cultured adipocytes. [Research Design and Methods]: BrCa1 gene expression, total and phosphorylated (P-) BrCa1, and ACC were analyzed in adipose tissue samples obtained from a total sample of 133 subjects. BrCa1 expression was also evaluated during in vitro differentiation of human adipocytes and 3T3-L1 cells. [Results]: BrCa1 gene expression was significantly up-regulated in both omental (OM; 1.36-fold, p = 0.002) and subcutaneous (SC; 1.49-fold, p = 0.001) adipose tissue from obese subjects. In parallel with increased BrCa1 mRNA, P-ACC was also up-regulated in SC (p = 0.007) as well as in OM (p = 0.010) fat from obese subjects. Consistent with its role limiting fatty acid biosynthesis, both BrCa1 mRNA (3.5-fold, p, This work was supported by research grants from the Ministerio de Educación y Ciencia SAF2008-02073 and SAF2009-10461), the Fundación Mutua Madrileña, and the Instituto de Salud Carlos III (ISCIIIRETIC RD06, CIBERObN).