Effective fraction from Simiao Wan prevents hepatic insulin resistant by inhibition of lipolysis via AMPK activation / 中国天然药物

Simiao Wan (SMW) is a traditional Chinese formula, including Atractylodis Rhizoma, Achyranthis Bidentatae Radix, Phellodendri Chinensis Cortex and Coicis Semen at the ratio of 1:1:2:2. It can be used to the treatment of diabetes. However, its bioactive compounds and underlying mechanism are unclear. This study aimed to screen the antilipolytic fraction from SMW and investigate its therapeutic mechanisms on hepatic insulin resistance. Different fractions of SMW were prepared by membrane separation combined with macroporous resin and their antilipolytic activities were screened in fasted mice. The effects of 60% ethanol elution (ESMW) on lipolysis were investigated in 3T3-L1 adipocytes stimulated by palmitic acid (PA) and high fat diet (HFD)-fed mice. In our study, ESMW is the bioactive fraction responsible for the antilipolytic activity of SMW and 13 compounds were characterized from ESMW by UHPLC-QTOF-MS/MS. ESMW suppressed protein kinase A (PKA)-hormone-sensitive lipase (HSL) related lipolysis and increased AMP-activated protein kinase (AMPK) phosphorylation in PA challenged 3T3-L1 adipocytes. AMPKα knockdown abolished the inhibitory effects of ESMW on IL-6 and HSL pSer-660, revealing that the antilipolytic and anti-inflammatory activities of ESMW are AMPK dependent. Furthermore, ESMW ameliorated insulin resistance and suppressed lipolysis in HFD-fed mice. It inhibited diacylglycerol accumulation in the liver and inhibited hepatic gluconeogenesis. Conditional medium collected from ESMW-treated 3T3-L1 cells ameliorated insulin action on hepatic gluconeogenesis in liver cells, demonstrating the antilipolytic activity contributed to ESMW beneficial effects on hepatic glucose production. In conclusion, ESMW, as the antilipolytic fraction of SMW, inhibited PKA-HSL related lipolysis by activating AMPK, thus inhibiting diacylglycerol (DAG) accumulation in the liver and thereby improving insulin resistance and hepatic gluconeogenesis.

Lipolysis and lipases in white adipose tissue – An update

Lipolysis is defined as the sequential hydrolysis of triacylglycerol (TAG) stored in cell lipid droplets. For many years, it was believed that hormone-sensitive lipase (HSL) and monoacylglycerol lipase (MGL) were the main enzymes catalyzing lipolysis in the white adipose tissue. Since the discovery of adipose triglyceride lipase (ATGL) in 2004, many studies were performed to investigate and characterize the actions of this lipase, as well as of other proteins and possible regulatory mechanisms involved, which reformulated the concept of lipolysis. Novel findings from these studies include the identification of lipolytic products as signaling molecules regulating important metabolic processes in many non-adipose tissues, unveiling a previously underestimated aspect of lipolysis. Thus, we present here an updated review of concepts and regulation of white adipocyte lipolysis with a special emphasis in its role in metabolism homeostasis and as a source of important signaling molecules.

New concepts in white adipose tissue physiology

Numerous studies address the physiology of adipose tissue (AT). The interest surrounding the physiology of AT is primarily the result of the epidemic outburst of obesity in various contemporary societies. Briefly, the two primary metabolic activities of white AT include lipogenesis and lipolysis. Throughout the last two decades, a new model of AT physiology has emerged. Although AT was considered to be primarily an abundant energy source, it is currently considered to be a prolific producer of biologically active substances, and, consequently, is now recognized as an endocrine organ. In addition to leptin, other biologically active substances secreted by AT, generally classified as cytokines, include adiponectin, interleukin-6, tumor necrosis factor-alpha, resistin, vaspin, visfatin, and many others now collectively referred to as adipokines. The secretion of such biologically active substances by AT indicates its importance as a metabolic regulator. Cell turnover of AT has also recently been investigated in terms of its biological role in adipogenesis. Consequently, the objective of this review is to provide a comprehensive critical review of the current literature concerning the metabolic (lipolysis, lipogenesis) and endocrine actions of AT.

Efeitos da ingestão de cafeína, café (Coffea arabica) e chá mate (Ilex paraguariensis) sobre a atividade lipolítica do tecido adiposo e parâmetros metabólicos em ratos submetidos ao exercício físico / Effects of the ingestion of caffeine, coffee (Coffea arabica) and roasted maté tea (Ilex paraguariensis) on the adipose tissue lipolytic activity and metabolic parameters on rats submitted to physical exercise

Introdução. O estoque excessivo de lipídeos no organismo está associado à diversas doenças crônicas não transmissíveis. O exercício físico aumenta a utilização dos lipídeos. A mobilização dos ácidos graxos (AG) é a primeira etapa para que eles sejam utilizados como fonte energética pelo músculo esquelético. Para otimizar esse processo, têm sido estudadas substâncias que poderiam aumentar a lipólise, como a cafeína. O café e o chá-mate contêm cafeína em sua composição. Objetivo. Comparar os efeitos da ingestão de cafeína, café e chá-mate sobre o desempenho físico, parâmetros metabólicos e lipólise em resposta ao exercício físico agudo em esteira rolante, em ratos Wistar. Métodos. O estudo foi divido em etapas 1 (exercício até a exaustão, n=15) e 2 (exercício com duração de 60 minutos, n=45). A amostra foi composta por cinco grupos: controle (C), controle exercício (CE), cafeína exercício (CFNE), café exercício (CAFE) e chá-mate exercício (CME). Na etapa 1, foram comparados o desempenho, as diferenças na massa corporal e na glicemia (pós versus pré-exercício) e a atividade lipolítica. Na etapa 2, foram comparadas as diferenças na massa corporal e na glicemia (pós versus pré-exercício), a atividade lipolítica, o lactato sanguíneo e o glicogênio muscular.Os dados foram apresentados segundo a estatística descritiva (média ± erro padrão). Os dados foram analisados através de modelos gerais lineares e os deltas através da técnica de contrastes ortogonais.Para verificar associação entre as variáveis de interesse foi utilizada a correlação linear de Pearson.Resultados.Na etapa 1 não foram observadas diferenças entre os grupos com relação ao desempenho. A massa corporal pós-exercício, quando comparada à pré-exercício, diminuiu nos grupos CE (188 por cento ), CFNE (273 por cento ), CAFE (319 por cento ) e CME (204 por cento ),quando comparados ao C.Não houve diferença para a variação de glicemia entre os grupos.Observou-se aumento de 92 por cento da lipólise no grupo CA...

Tejido adiposo / Adipose tissue

El concepto clásico afirma que el tejido adiposo (TA) es parte del tejido conjuntivo y está compuesto por células que almacenan lípidos llamados adipocitos. La distribución del TA es diferente según los sexos. En las mujeres predomina la distribución ginecoide, mientras que en los varones lo hace en la mitad superior (distribución androide). En el hombre hay un predominio de la grasa visceral, con mayor actividad lipolítica. En cambio, en la mujer se almacena energía y sólo la libera en casos extremos como el embarazo y la lactancia, predominando la lipogénesis. La lipólisis y la lipogénesis son procesos simultáneos y el predominio de uno de ellos determinará la dirección del metabolismo del TA. En la actualidad se considera que el TA blanco constituye, como la piel, un órgano productor de ciertas sustancias- adipoquinas- con acción endocrina, paracrina y autocrina. La gran cantidad de receptores para distintos estímulos explican la sensibilidad y adaptación del TA a las múltiples circunstancia metabólicas.

Differences in lipogenesis and lipolysis in obese and non-obese adult human adipocytes

It has been proposed that differences in adipocyte function and/or metabolism between obese and lean individuáis may manifest themselves in functional adipose tissue abnormalities that lead to metabolic disorders in obesity. We studied lipogenesis and lipolysis of omental adipocytes from obese (OB) and non-obese (NOB) humans. The specific activity of the lipogenic marker enzyme G3PDH was 50 percent lower in total adipocytes of OB compared to that of NOB subjects. Omental adipocytes from OB subjects also had lower basal lipolytic levéis, and a lower lipolytic response to p-adrenergic stimulus. Cholesterol depletion of adipocyte plasma membrane using methyl β-cyclodextrin caused a lipolytic effect on adipocytes of both groups together, but when obese and lean subjects were analyzed separately, the response was significant only in the obese. We present evidence of a different lipogenic and lipolytic profile in obese individuáis' omental adipocytes, and propose a relevant role of plasma membrane cholesterol, where the impact of its removal in OB and NOB adipocyte lipolysis differs.

O tecido adiposo como órgão endócrino: da teoria à prática: [revisão] / Adipose tissue as an endocrine organ: from theory to practice: [review]

OBJETIVOS Mostrar os avanços na pesquisa sobre o papel fisiológico do tecido adiposo branco, ressaltando o seu papel endócrino em processos inflamatórios, no comportamento alimentar, na sensibilização à insulina e na modulação do processo de aterogênese. Abordar o potencial papel do tecido adiposo como fonte de células-tronco para regeneração de tecidos, com especial ênfase para a adipogênese e suas conseqüências para a geração de obesidade. FONTES DE DADOS: Informações importantes constantes da literatura científica foram compiladas de modo a que esta leitura contenha uma síntese esclarecedora dos aspectos mencionados acima. SÍNTESE DOS DADOS:O tecido adiposo possui, além das suas funções clássicas como principal estoque de energia metabólica, suprindo as necessidades energéticas em períodos de carência mediante a lipólise, a capacidade de sintetizar e secretar vários hormônios, as adipocinas. Estas agem em diversos processos, como o controle da ingestão alimentar (leptina) e o controle da sensibilidade à insulina e de processos inflamatórios (TNF-alfa, IL-6, resistina, visfatina, adiponectina). Além disso, como o tecido adiposo contém também células indiferenciadas, tem a habilidade de gerar novos adipócitos, regenerando o próprio tecido (adipogênese), bem como originar outras células (mioblastos, condroblastos, osteoblastos), fato este que tem grande potencial terapêutico em futuro não muito distante. CONCLUSÃO: Amplia-se o leque de possibilidades funcionais do tecido adiposo. A compreensão dessas potencialidades pode fazer deste tecido o grande aliado no combate de moléstias que atualmente vêm assumindo proporções epidêmicas (obesidade, diabetes melito, hipertensão arterial e arteriosclerose), nas quais o tecido adiposo ainda é tido como um grande vilão.

OBJECTIVES: To describe the advances in research into the physiological role of white adipose tissue, with emphasis on its endocrinal role in inflammatory processes, feeding behavior, insulin sensitization and modulation of the atherogenetic process. To deal with the potential role of adipose tissue as a source of stem cells for regeneration of tissues, with special emphasis on adipogenesis and its consequences for development of obesity. SOURCES: Important information was compiled from the scientific literature in order that this analysis contains an explanatory synthesis of the aspects mentioned above. SUMMARY OF THE FINDINGS In addition to its classical functions as primary metabolic energy store, meeting energy requirements during periods of deprivation by means of lypolisis, adipose tissue also has the capacity to synthesize and secrete a variety of hormones - the adipokines. These are active in a range of processes, such as control of nutritional intake (leptin) and control of sensitivity to insulin and inflammatory processes (TNF-alpha, IL-6, resistin, visfatin, adiponectin). Furthermore, since adipose tissue also contains undifferentiated cells, it has the ability to generate new adipocytes, regenerating its own tissue (adipogenesis), and also the ability to give rise to other cells (myoblasts, chondroblasts, osteoblasts), which has great therapeutic potential in the not-too-distant future. CONCLUSIONS: The range of functional possibilities of adipose tissue has widened. An understanding of these potentials could make this tissue a great ally in the fight against conditions that are currently assuming epidemic proportions (obesity, diabetes mellitus, arterial hypertension and arteriosclerosis) and in which adipose tissue is still seen as the enemy.

Atividade lipolítica do leite com células somáticas ajustadas para diferentes níveis / Lipolytic activity of milk with different somatic cells levels

Estimou-se a origem da atividade lipolítica do leite com contagens de células somáticas (CCS) ajustadas para diferentes níveis. A partir de lotes de leite cru com baixa (100.000 cel/ml) e alta (1.000.000 cel/ml) CCS, formaram-se três tratamentos: A) leite com baixa CCS; B) leite com alta CCS; C) leite originalmente com baixa CCS e com adição de células somáticas. O leite foi submetido à pasteurização e armazenado por 21 dias sob refrigeração a 6ºC. Durante o período de armazenamento, foram coletadas amostras nos dias 1, 7, 14 e 21 para avaliação da concentração de ácidos graxos livres (AGL). Não foi observado efeito de tratamento sobre a concentração de AGL, durante todo o período de armazenamento e nem em cada dia de coleta isoladamente, cujas médias de AGL, após 21 dias, foram de 0,181; 0,159 e 0,153meq/kg, respectivamente, para os tratamentos A, B e C. Observou-se efeito do tempo de armazenamento sobre a concentração de AGL do leite, independentemente dos tratamentos, com teores de AGL de 0,121meq/kg para o dia 1 e de 0,219 para o dia 21. Pode-se concluir que, independentemente da contagem de células somáticas do leite cru, ocorre aumento da lipólise do leite pasteurizado durante o período de armazenamento. A adição de células somáticas ao leite, originalmente com baixa CCS, não aumentou a taxa de lipólise durante o armazenamento refrigerado

The lipolytic activity of milk with different somatic cell counts (SCC) was investigated in samples with low (100,000 cells.ml-1) and high (1,000,000 cells.mlÕ) SCC in order to obtain the following treatments: A) low SCC milk; B) high SCC milk; C) low SCC milk with somatic cells added, taken from high SCC milk. All samples were pasteurized and kept refrigerated at 6ºC for 21 days. Repeated measures during storage time were performed from pasteurized milk at days 1, 7, 14 and 21 to evaluate free fatty acid (FFA) concentrations. No effect of treatments was observed on milk FFA concentration during storage period, nor during each day of sampling, with FFA averaging 0.181; 0.159 and 0.153meq/kg for treatments A, B and C, respectively. FFA concentration in pasteurized milk increased during the storage period, independently of the milk SCC, as the level of FFA was 0.121 meq/kg on day 1 and 0.219 on day 21. Addition of somatic cells to low somatic cell milk did not increase lipolysis rate of milk during refrigerated storage. It can be concluded that pasteurized milk fat breakdown during refrigerated storage is not related to enzymes from somatic cells

Efeito da remoção de células somáticas pela microfiltração sobre a lipólise do leite / Effect of somatic cell removal by microfiltration on the lipolysis of milk

O objetivo do presente estudo foi avaliar o efeito da retirada mecânicadas células somáticas do leite cru sobre a taxa de lipólise durante o armazenamento refrigerado do leite pasteurizado. O delineamento experimental utilizado foi totalmente casualizado, com três repetições e arranjo fatorial de tratamentos 2 X 2 X 2, constituídos por dois nível de gordura do leite (desnatado e integral), dois níveis de contagem de células somáticas (CCS baixa - CCSB e CCS alta - CCSA), e pela aplicação ou não da microfiltração ao leite. Três lotes de leite cru CCSB (75.000 cél./mL) e CCSA (1.150.000 cél./mL) foram obtidos de vacas selecionadas e submetidos ao desnate centrífugo, à microfiltração em sistema a vácuo, sendo em seguida pasteurizados e armazenados por 21 dias sob refrigeração a 6ºC. Foram realizadas medidas repetidas no tempo, as quais corresponderam aos dias de coleta do leite pasteurizado durante o período de armazenamento (1, 7, 14 e 21). A microfiltração associada ao desnate foram eficazes na remoção das células somáticas do leite, com reduções de 92,5 e 99,5% para o leite CCSB e CCSA, respectivamente. A lipólise do leite aumentou em função do tempo de armazenamento e foi maior para o leite microfiltrado, contudo não sofreu influência da CCS. Independentemente da CCS, ocorreu aumento da lipólise do leite pasteurizado durante o período de armazenamento.

The objective of this study was to evaluate the effects of raw milk somatic cell removal by microfiltration on lipolysis of pasteurized milk during refrigerated storage. A completely randomized design was used, with 3 repetitions and a 2 X 2 X 2 factorial arrangement of treatments as follow: milk fat level (skimmed and whole milk), two different levels of somatic cell counts - low somatic cell count (LSCC) and high somatic cell count (HSCC) - and, use of microfiltration ornot. LSCC raw milk - 75,000 cells/ml - and HSCC raw milk - 1,150,000 cells/ml - were obtained from selected cows, skimmed and submitted to vacuum microfiltration. Milk from all treatments was pasteurized and kept refrigerated at 6ºC for 21 days. Repeated measures during storage time were taken from pasteurized milk at days 1, 7, 14 and 21. The application of milk microfiltration was efficient on somatic cell removal, with reduction of 92,5 and 99,5% for LSCC and HSCC,repectively. Lipolysis of milk was increased during storage period and was higher for milk submitted to icrofiltration, however no effect of SCC was observed. Lipolysis in pasteurized milk increased independently of SCC, during its refrigerated storage period.

O tecido adiposo como centro regulador do metabolismo / The adipose tissue as a regulatory center of the metabolism

Os avanços da pesquisa sobre as propriedades metabólicas do tecido adiposo e as recentes descobertas sobre sua capacidade em produzir hormônios atuantes em processos fisiológicos e fisiopatológicos, estão revolucionando conceitos sobre a sua biologia. O seu envolvimento em processos como obesidade, diabetes mellitus tipo 2, hipertensão arterial, arteriosclerose, dislipidemias, processos inflamatórios agudos e crônicos, entre outros, indicam que a compreensão das suas propriedades funcionais contribuirão para melhorar o prognóstico daquelas doenças, cuja prevalência vem crescendo de forma preocupante. Nesta revisão, abordamos aspectos funcionais dos adipócitos, como o metabolismo, a participação na homeostase energética, a sua habilidade endócrina e a adipogênese, entendida como a capacidade de pré-adipócitos, presentes no parênquima do tecido, de se diferenciarem em novos adipócitos e reconstituírem o tecido. Além disso, estamos incluindo estudos sobre as relações entre o tecido adiposo e a glândula pineal, aspecto novo e pouco conhecido, mas, como será visto, muito promissor da fisiologia do adipócito com possíveis repercussões favoráveis para a terapêutica das moléstias relacionadas com a obesidade.

The recent progress in the research about the metabolic properties of the adipose tissue and the discovery of its ability to produce hormones that are very active in pathophysiologic as well as physiologic processes is rebuilding the concepts about its biology. Its involvement in conditions like obesity, type 2 diabetes mellitus, arterial hypertension, arteriosclerosis, dislipidemias and chronic and acute inflammatory processes indicate that the understanding of its functional capacities may contribute to improve the prognosis of those diseases whose prevalence increased in a preoccupying manner. Here we review some functional aspects of adipocytes, such as the metabolism, its influence on energy homeostasis, its endocrine ability and the adipogenesis, i.e., the potential of pre-adipocytes present in adipose tissue stroma to differentiate into new adipocytes and regenerate the tissue. In addition, we are including some studies on the relationship between the adipose tissue and the pineal gland, a new and poorly known, although, as will be seen, very promising aspect of adipocyte physiology together with its possible favorable repercussions to the therapy of the obesity related diseases.

Efeitos do nível de células somáticas e de gordura no leite, da temperatura de armazenamento e da multiplicaçäo microbiana sobre a proteólise e lipólise do leite pasteurizado / Effect of somatic cell and milk fat levels, temperature of storage and microbial growth on proteolysis and lipolysis of pasteurize d fluid milk during shelf-life storage

Os objetivos do presente estudo foram os de: 1) avaliar o efeito do nível de células somáticas (CCS) no leite e da temperatura de armazenagem (0,5 e 6,0 ºC) sobre a proteólise e lipólise do leite pasteurizado, homogeneizado, com 2 por cento de gordura e estimar o período de tempo, em número de dias, para que o leite pasteurizado com diferentes níveis de CCS desenvolva alterações de sabor devido à lipólise e proteólise, independente de deterioração de origem microbiana; 2) avaliar o efeito do nível de gordura do leite (1,2 e 3,25 por cento) sobre a proteólise e lipólise no leite pasteurizado, conservado e com diferentes níveis de CCS; 3) estimar o número de dias para que o leite pasteurizado, com 2 por cento de gordura e com diferentes níveis CCS desenvolva alterações das propriedades organolépticas ocasionadas pela lipólise e proteólise resultantes da ação combinada de enzimas presentes no leite de origem microbiana...

Claudio Bernard y la emulsión de la grasa (o la Bella Durmiente 150 años después) / Claudio Bernard and fat emulsion (or, Sleeping Beauty 150 years leter)

En 1848, Claude Bernard descubrió la función lipolítica del páncreas exócrino. Su procedimiento experimental fue único y el siempre afirmó que era fácilmente reproducible. Este trabajo repite los experimentos bernardinos de emulsión y saponificación de la grasa, y Ia originalidad de esta idea radica en que los experimentos realizados, fueron los mismos que el escribió en sus protocolos de laboratorio. También se aborda el tema de los papeles personales del científico francés. Los resultados que se obtuvieron fueron asombrosamente similares a los bernardinos, lo que confirma la validez de sus experimentos y conclusiones, así como sus ideas sobre la repetibilidad experimental en la medicina científica. Considerando las dificultades quirúrgicas que se presentaron, Claude Bernard debe saber contado con gran destreza manual, en una época en la que se carecía del apoyo técnico actual.

Carbohydrate-lipid interactions during gestation and their control by insulin

1. During the first two thirds of gestation, coinciding with a minimal accretion by the conceptus, the mother is in an anabolic state which is supported by her hyperphagia and the more efficient conservation of exogenous nutrients when she eats. During this phase maternal fat deposits are accumulated thanks to the enhancement in adipose tissue lipogenic and glycerolgenic activity. In contrast, in the latter part of gestation, the rapid fetal growth is sustained by the intense transfer of nutrients from maternal circulation. 2 Glucose is quantitatively the most abundant of the several substrates that cross the placenta and despite increased maternal gluconeogenesis this transfer is responsible for the maternal tendency to hypoglycemia. This causes a switch to a net catabolic state which is especially evident in the net breakdown of fat depots. 3. Enhanced release of adipose tissue lipolytic products, free fatty acids (FFA) and glycerol, facilitates the liver synthesis of triglycerides and their later release into circulation associated to very low-density lipoprotein (VLDL). Glycerol is also used as an important gluconeogenic substrate and FFAs are broken down through ß-oxidation for ketone body synthesis. Flow through these pathways becomes increased when food is withheld and this actively contributes to the availability of fuels to the fetus which becomes partially preserved from maternal metabolic insult. Increased liver production of VLDL-triglycerides and decreased extrahepatic lipoprotein lipase contribute to exaggerated maternal hypertriglyceridemia which, besides being a floating metabolic reserve for emergency conditions such as starvation, constitutes an essential substrate for milk synthesis around parturition in preparation for lactation. 4. While the maternal anabolic tendencies found during the first two-thirds of gestation seem to be facilitated by hyperinsulinemia in the presence of a normal responsiveness to the hormone, it is proposed that most of the metabolic changes taking place during the last third of gestation seem to be caused by the insulin-resistant state which is consistently present at this stage, since its reversion caused by sustained exaggerated hyperinsulinemia also reverts several of these metabolic adaptations

Alterations of lipid kinetics and lipoprotein lipase activity in jaundiced tumor bearing rats

Obstructive jaundice is associated with high perioperative morbidity and mortality, and preoperative biliary decompression is still controversial. Profound alterations in intermediary metabolism have been observed with obstructive jaundice. To determine the effect of the common bile duct (CBD) obstruction on lipid metabolism in tumor-bearing animals, free fatty acid (FFA) and very low density lipoprotein-associated triglyceride (VLDL-TG) kinetics were assessed in 20 tumor bearing (subcutaneous MCA sarcoma) Fischer-344 rats, using an obstructive jaundice model. The animals were studied after chronic vascular catheterization, in an unanesthetized, undisturbed state. They were separated into 4 groups: Normal controls (CTL), Tumor-bearing non-jaundiced rats (TBR), Non Tumor Bearing-Jaundiced (NTB-J), Tumor Bearing (tumor burden: 1O per cent body weight)-Jaundiced (TBR-J). All rats were studied 7 days after CBD ligation, or at 1O per cent tumor burden. VLDL-TG and FFA kinetics were assessed by constant infusion of 3H-palmitate-labeled VLDL-TG, and l4C-palmitate bound to albumin, respectively. FFA rate of appearance (FFA-Ra) and clearance (FFA-CI), VLDL-TG rate of appearance (VLDL-TG-Ra) and clearance (VLDL-TG-CI) were determined at steady-states. Tumor burden signiricantly affects FFA-Ra and FFA-CI, as well as VLDL-TG-CI, while CBD ligation selectively affects VLDL-TG-Ra and VLDL-TG-CI. There was significant interaction between tumor burden and jaundice in FFA-Ra. CBD decompression increased significantly VLDL-TG-CI. We conclude that, in jaundiced tumor-bearing rats, tumor burden predominantly affects lipolysis, while CBD obstruction primarily affects triglyceride synthesis and clearance. Lipoprotein lipase (LPL) activity was also markedly decreased by the presence of jaundice and tumor burden, with the associated decrease in the clearance of VLDL-TG.

O tecido adiposo e a diminuiçäo dos triacilgliceróis plasmáticos no rato diabético tireoidectomizado / Adipose tissue and decrease of plasmatic triacylglycerol in thyroidectomized diabetic rat

Neste trabalho säo estudadas a participaçäo do tecido adiposo e a atividade da lípase lipoprotéica (LLP) na diminuiçäo dos níveis de triacilgliceróis (TG) plasmáticos de ratos diabéticos tireoidectomizados. Os resultados mostram que a medida da atividade da lípase lipoprotéica se apresentou mais baixa no tecido adiposo dos ratos diabéticos tireoidectomizados, näo podendo explicar a queda dos níveis de TG após a tireoidectomia dos ratos diabéticos. Poroutro lado, verificou-se que o tecido adiposo epididimal daqueles animais apresentaram menor liberaçäo de AGL e glicerol para o meio de incubaçäo. Conclui-se que a reduçäo dos TG plásmáticos de ratos diabéticos tireoidectomizados é decorrente, pelo menos em parte, da diminuiçäo do processo lipolítico no tecido adiposo