[Aging and metabolism: changes and regulation].

Science.gov (United States)

Ortiz, Genaro Gabriel; Arias-Merino, Elva D; Velázquez-Brizuela, Irma E; Pacheco-Moisés, Fermín P; Flores-Alvarado, Luis J; Torres-Sánchez, Erandis D; Cortés-Enríquez, Fernando; González-Renovato, Erika D; Ortiz-Velázquez, Irma G

2012-09-01

Studies about the effects of aging in the physiology and metabolism are increasingly, one of its objectives is to help implement programs to improve the quality of life and prevent disability in elderly. It is relevant to mention that, during aging, there is a natural metabolic deceleration, a series of changes in the regulation of energy are produced, which contributes to loss of weight and fat; the changes in the regulation of caloric intake contribute to increase the susceptibility to energy imbalance both positive and negative, which is associated with a deterioration in health. However, to grow old, is not a death sentence for metabolism, on the other hand, it can be controlled by maintaining an active lifestyle, coupled with this, research has shown that the metabolism'can be regulated by a synchronized clock (circadian rhythms), which is mediated by regulatory proteins, this relationship ensures the proper functioning of the cells and therefore good health. The aim of this review is to provide updated information on the energy- metabolism-regulation and its relationship with the great variety of components involved in energy expenditure that accompany aging, to analyze the regulation of this system to improve the quality of life and maintenance of health in old age.

Ananas comosus L. Leaf Phenols and p-Coumaric Acid Regulate Liver Fat Metabolism by Upregulating CPT-1 Expression

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Weidong Xie

2014-01-01

Full Text Available In this study, we aimed to investigate the effect and action mechanisms of pineapple leaf phenols (PLPs on liver fat metabolism in high-fat diet-fed mice. Results show that PLP significantly reduced abdominal fat and liver lipid accumulation in high-fat diet-fed mice. The effects of PLP were comparable with those of FB. Furthermore, at the protein level, PLP upregulated the expression of carnitine palmitoyltransferase 1 (CPT-1, whereas FB had no effects on CPT-1 compared with the HFD controls. Regarding mRNA expression, PLP mainly promoted the expression of CPT-1, PGC1a, UCP-1, and AMPK in the mitochondria, whereas FB mostly enhanced the expression of Ech1, Acox1, Acaa1, and Ehhadh in peroxisomes. PLP seemed to enhance fat metabolism in the mitochondria, whereas FB mainly exerted the effect in peroxisomes. In addition, p-coumaric acid (CA, one of the main components from PLP, significantly inhibited fat accumulation in oleic acid-induced HepG2 cells. CA also significantly upregulated CPT-1 mRNA and protein expressions in HepG2 cells. We, firstly, found that PLP enhanced liver fat metabolism by upregulating CPT-1 expression in the mitochondria and might be promising in treatment of fatty liver diseases as alternative natural products. CA may be one of the active components of PLP.

Fat and carbohydrate metabolism during submaximal exercise in children.

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Aucouturier, Julien; Baker, Julien S; Duché, Pascale

2008-01-01

During exercise, the contribution of fat and carbohydrate to energy expenditure is largely modulated by the intensity of exercise. Age, a short- or long-term diet enriched in carbohydrate or fat substrate stores, training and gender are other factors that have also been found to affect this balance. These factors have been extensively studied in adults from the perspective of improving performance in athletes, or from a health perspective in people with diseases. During the last decade, lifestyle changes associated with high-energy diets rich in lipid and reduced physical activity have contributed to the increase in childhood obesity. This lifestyle change has emerged as a serious health problem favouring the early development of cardiovascular diseases, insulin resistance or type 2 diabetes mellitus. Increasing physical activity levels in young people is important to increase energy expenditure and promote muscle oxidative capacity. Therefore, it is surprising that the regulation of balance between carbohydrate and lipid use during exercise has received much less attention in children than in adults. In this review, we have focused on the factors that affect carbohydrate and lipid metabolism during exercise and have identified areas that may be relevant in explaining the higher contribution of lipid to energy expenditure in children when compared with adults. Low muscle glycogen content is possibly associated with a low activity of glycolytic enzymes and high oxidative capacity, while lower levels of sympathoadrenal hormones are likely to favour lipid metabolism in children. Changes in energetic metabolism occurring during adolescence are also dependent on pubertal events with an increase in testosterone in boys and estrogen and progesterone in girls. The profound effects of ovarian hormones on carbohydrate and fat metabolism along with their effects on oxidative enzymes could explain that differences in substrate metabolism have not always been observed between

A high throughput live transparent animal bioassay to identify non-toxic small molecules or genes that regulate vertebrate fat metabolism for obesity drug development

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Woollett Laura A

2008-08-01

142 antagonists may be effective non-toxic anti-obesity therapeutics. Conclusion Owing to the apparently high level of evolutionary conservation of signal transduction pathways regulating lipid metabolism, the zebrafish can be useful for identifying non-toxic small molecules or pharmacological target gene products for developing molecular therapeutics for treating clinical obesity. Our results support the promising potential in applying NAD or resveratrol where the underlying target protein likely involves Sirtuin family member proteins. Furthermore data supports future studies focused on determining whether there is a high concentration window for resveratrol that is effective and non-toxic in high fat obesity murine models.

Detrimental and protective fat: body fat distribution and its relation to metabolic disease.

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Booth, Andrea; Magnuson, Aaron; Foster, Michelle

2014-01-01

Obesity is linked to numerous comorbidities that include, but are not limited to, glucose intolerance, insulin resistance, dyslipidemia, and cardiovascular disease. Current evidence suggests, however, obesity itself is not an exclusive predictor of metabolic dysregulation but rather adipose tissue distribution. Obesity-related adverse health consequences occur predominately in individuals with upper body fat accumulation, the detrimental distribution, commonly associated with visceral obesity. Increased lower body subcutaneous adipose tissue, however, is associated with a reduced risk of obesity-induced metabolic dysregulation and even enhanced insulin sensitivity, thus, storage in this region is considered protective. The proposed mechanisms that causally relate the differential outcomes of adipose tissue distribution are often attributed to location and/or adipocyte regulation. Visceral adipose tissue effluent to the portal vein drains into the liver where hepatocytes are directly exposed to its metabolites and secretory products, whereas the subcutaneous adipose tissue drains systemically. Adipose depots are also inherently different in numerous ways such as adipokine release, immunity response and regulation, lipid turnover, rate of cell growth and death, and response to stress and sex hormones. Proximal extrinsic factors also play a role in the differential drive between adipose tissue depots. This review focuses on the deleterious mechanisms postulated to drive the differential metabolic response between central and lower body adipose tissue distribution.

Effect of increasing body condition on key regulators of fat metabolism in subcutaneous adipose tissue depot and circulation of nonlactating dairy cows.

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Locher, L; Häussler, S; Laubenthal, L; Singh, S P; Winkler, J; Kinoshita, A; Kenéz, Á; Rehage, J; Huber, K; Sauerwein, H; Dänicke, S

2015-02-01

In response to negative energy balance, overconditioned cows mobilize more body fat than thin cows and subsequently are prone to develop metabolic disorders. Changes in adipose tissue (AT) metabolism are barely investigated in overconditioned cows. Therefore, the objective was to investigate the effect of increasing body condition on key regulator proteins of fat metabolism in subcutaneous AT and circulation of dairy cows. Nonlactating, nonpregnant dairy cows (n=8) investigated in the current study served as a model to elucidate the changes in the course of overcondition independent from physiological changes related to gestation, parturition, and lactation. Cows were fed diets with increasing portions of concentrate during the first 6wk of the experiment until 60% were reached, which was maintained for 9wk. Biopsy samples from AT of the subcutaneous tailhead region were collected every 8wk, whereas blood was sampled monthly. Within the experimental period cows had an average BW gain of 243±33.3 kg. Leptin and insulin concentrations were increased until wk 12. Based on serum concentrations of glucose, insulin, and nonesterified fatty acids, the surrogate indices for insulin sensitivity were calculated. High-concentrate feeding led to decreased quantitative insulin sensitivity check index and homeostasis model assessment due to high insulin and glucose concentrations indicating decreased insulin sensitivity. Adiponectin, an adipokine-promoting insulin sensitivity, decreased in subcutaneous AT, but remained unchanged in the circulation. The high-concentrate diet affected key enzymes reflecting AT metabolism such as AMP-activated protein kinase and hormone-sensitive lipase, both represented as the proportion of the phosphorylated protein to total protein, as well as fatty acid synthase. The extent of phosphorylation of AMP-activated protein kinase and the protein expression of fatty acid synthase were inversely regulated throughout the experimental period, whereas

Role and metabolism of free leucine in skeletal muscle in protein sparing action of dietary carbohydrate and fat

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Nakano, Kiwao; Ishikawa, Tamotsu

1977-01-01

Feeding rats with either a carbohydrate meal or a fat meal to the previously fasted rats caused significant decrease in urinary output of urea and total nitrogen. The content of free leucine in skeletal muscle decreased in the rats fed either a carbohydrate meal or a fat meal. Feeding of either a carbohydrate meal or a fat meal stimulated incorporation of L-leucine-1- 14 C into protein fraction of skeletal muscle and reduced its oxidation to 14 CO 2 . These results suggest that the metabolism of leucine is under nutritional regulation and that the decrease in content of free leucine in skeletal muscle might be caused by enhanced reutilization of leucine into protein by the feeding of a carbohydrate meal or a fat meal. The role of free leucine in skeletal muscle as a regulator of protein turnover in the tissue are discussed in relation to the metabolism of this branched chain amino acid. (auth.)

Fat metabolism during exercise in patients with mitochondrial disease

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Jeppesen, Tina Dysgaard; Orngreen, Mette Cathrine; Van Hall, Gerrit

2009-01-01

. Fat metabolism was determined by means of indirect calorimetry and stable isotope technique in patients and healthy subjects. Patients carried various types and loads (mean [SE], 72% [5%]) of mitochondrial DNA (mtDNA) mutations in skeletal muscle. All subjects exercised at the same absolute workload......OBJECTIVE: To determine whether patients with defects of the respiratory chain have metabolic adaptations that promote a preferential use of fats or carbohydrates, similar to what is observed in metabolic myopathies affecting glycolysis or fat oxidation. DESIGN: Causation and case-control study...... (mean [SE], 65 [10] W), corresponding to 72% (in patients) and 30% (in healthy subjects) of maximum oxygen consumption. SETTING: Neuromuscular research unit. PARTICIPANTS: Ten patients with mtDNA mutations and 10 sex-matched healthy subjects. MAIN OUTCOME MEASURES: Fat turnover, plasma concentrations...

Isocaloric high-fat feeding directs hepatic metabolism to handling of nutrient imbalance promoting liver fat deposition

KAUST Repository

Diaz Rua, Ruben; Van Schothorst, E. M.; Keijer, J.; Palou, A.; Oliver, P.

2016-01-01

Background/Objectives: Consumption of fat-rich foods is associated with obesity and related alterations. However, there is a group of individuals, the metabolically obese normal-weight (MONW) subjects, who present normal body weight but have metabolic features characteristic of the obese status, including fat deposition in critical tissues such as liver, recognized as a major cause for the promotion of metabolic diseases. Our aim was to better understand metabolic alterations present in liver of MONW rats applying whole genome transcriptome analysis. Methods: Wistar rats were chronically fed a high-fat diet isocaloric relative to Control animals to avoid the hyperphagia and overweight and to mimic MONW features. Liver transcriptome analysis of both groups was performed. Results: Sustained intake of an isocaloric high-fat diet had a deep impact on the liver transcriptome, mainly affecting lipid metabolism. Although serum cholesterol levels were not affected, circulating triacylglycerols were lower, and metabolic adaptations at gene expression level indicated adaptation toward handling the increased fat content of the diet, an increased triacylglycerol and cholesterol deposition in liver of MONW rats was observed. Moreover, gene expression pointed to increased risk of liver injury. One of the top upregulated genes in this tissue was Krt23, a marker of hepatic disease in humans that was also increased at the protein level.Conclusion:Long-term intake of a high-fat diet, even in the absence of overweight/obesity or increase in classical blood risk biomarkers, promotes a molecular environment leading to hepatic lipid accumulation and increasing the risk of suffering from hepatic diseases.

Isocaloric high-fat feeding directs hepatic metabolism to handling of nutrient imbalance promoting liver fat deposition

KAUST Repository

Diaz Rua, Ruben

2016-03-22

Background/Objectives: Consumption of fat-rich foods is associated with obesity and related alterations. However, there is a group of individuals, the metabolically obese normal-weight (MONW) subjects, who present normal body weight but have metabolic features characteristic of the obese status, including fat deposition in critical tissues such as liver, recognized as a major cause for the promotion of metabolic diseases. Our aim was to better understand metabolic alterations present in liver of MONW rats applying whole genome transcriptome analysis. Methods: Wistar rats were chronically fed a high-fat diet isocaloric relative to Control animals to avoid the hyperphagia and overweight and to mimic MONW features. Liver transcriptome analysis of both groups was performed. Results: Sustained intake of an isocaloric high-fat diet had a deep impact on the liver transcriptome, mainly affecting lipid metabolism. Although serum cholesterol levels were not affected, circulating triacylglycerols were lower, and metabolic adaptations at gene expression level indicated adaptation toward handling the increased fat content of the diet, an increased triacylglycerol and cholesterol deposition in liver of MONW rats was observed. Moreover, gene expression pointed to increased risk of liver injury. One of the top upregulated genes in this tissue was Krt23, a marker of hepatic disease in humans that was also increased at the protein level.Conclusion:Long-term intake of a high-fat diet, even in the absence of overweight/obesity or increase in classical blood risk biomarkers, promotes a molecular environment leading to hepatic lipid accumulation and increasing the risk of suffering from hepatic diseases.

Interactions between host metabolism, immune regulation, and the gut microbiota in diet-associated obesity and metabolic dysfunction

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Andersen, Daniel

The increase in the prevalence of obesity and obesity-associated complications such as the metabolic syndrome is becoming a global challenge. Dietary habits and nutrient consumption modulates host homeostasis, which manifests in various diet-induced complications marked by changes in host...... metabolism and immune regulation, which are intricately linked. In addition, diet effectively shapes the gut microbiota composition and activity, which in turn interacts with the host to modulate host metabolism and immune regulation. In the three studies included in this PhD thesis, we have explored...... the impact of specific dietary components on host metabolic function, immune regulation and gut microbiota composition and activity. In the first study, we have characterized the effect of a combined high-fat and gliadin-rich diet, since dietary gliadin has been reported to be associated with intestinal...

Individuals with Metabolically Healthy Overweight/Obesity Have Higher Fat Utilization than Metabolically Unhealthy Individuals

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Arturo Pujia

2016-01-01

Full Text Available The mechanisms underlying the change in phenotype from metabolically healthy to metabolically unhealthy obesity are still unclear. The aim of this study is to investigate whether a difference in fasting fat utilization exists between overweight/obese individuals with a favorable cardiovascular risk profile and those with Metabolic Syndrome and Type 2 diabetes. Furthermore, we sought to explore whether there is an association between fasting fat utilization and insulin resistance. In this cross-sectional study, 172 overweight/obese individuals underwent a nutritional assessment. Those with fasting glucose ≥126 mg/dL or antidiabetic treatment were considered to be diabetics. If at least three of the NCEP criteria were present, they had Metabolic Syndrome, while those with less criteria were considered to be healthy overweight/obese. An indirect calorimetry was performed to estimate Respiratory Quotient, an index of nutrient utilization. A lower Respiratory Quotient (i.e., higher fat utilization was found in healthy overweight/obese individuals than in those with Metabolic Syndrome and Type 2 diabetes (0.85 ± 0.05; 0.87 ± 0.06; 0.88 ± 0.05 respectively, p = 0.04. The univariate and multivariable analysis showed a positive association between the Respiratory Quotient and HOMA-IR (slope in statistic (B = 0.004; β = 0.42; p = 0.005; 95% Confidence interval = 0.001–0.006. In this study, we find, for the first time, that the fasting Respiratory Quotient is significantly lower (fat utilization is higher in individuals who are metabolically healthy overweight/obese than in those with metabolically unhealthy obesity. In addition, we demonstrated the association between fat utilization and HOMA-IR, an insulin resistance index.

FTO gene associated fatness in relation to body fat distribution and metabolic traits throughout a broad range of fatness

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Kring, Sofia I I; Holst, Claus; Zimmermann, Esther

2008-01-01

A common single nucleotide polymorphism (SNP) of FTO (rs9939609, T/A) is associated with total body fatness. We investigated the association of this SNP with abdominal and peripheral fatness and obesity-related metabolic traits in middle-aged men through a broad range of fatness present already...

Total body fat as a possible indicator of metabolic syndrome in adults

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Edgar Navarro Lechuga

2016-09-01

Full Text Available Introduction: The metabolic syndrome is a set of factors related to insulin resistance, which increases the likelihood of coronary events. It is important timely onset identifying to reduce its prevalence. Objective: To explore the percentage of total body fat as indicator of metabolic syndrome in adults from Soledad, Colombia. Material and Methods: Cross-sectional study. n=99 adults (non-pregnant, nor subjects with psychomotor disturbances. Blood samples were taken: total cholesterol, HDL; triglycerides and glucose. Waist circumference, Body Mass Index and body fat by bioimpedance and skinfold thickness were measured. Diagnosis of metabolic syndrome was made according to NHLBI/AHA, ATP III and IDF criteria. Subjects with and without metabolic syndrome according to total body fat averages were compared. Results: The average percentage of body fat was higher (p0.05 in the classification according to ATP III in women, where the average fat percentage was 39.31 % in those with metabolic syndrome and 37.7% in those not suffering. Conclusions: Subjects with metabolic syndrome have higher mean total body fat, significantly, compared with those who did not, so it could be considered the values of total body fat obtained by bioimpedance as future indicators of metabolic syndrome, both as screening and control.

Tissue Specific Expression Of Sprouty1 In Mice Protects Against High Fat Diet Induced Fat Accumulation, Bone Loss, And Metabolic Dysfunction

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Urs, Sumithra; Henderson, Terry; Le, Phuong; Rosen, Clifford J.; Liaw, Lucy

2012-01-01

We recently characterized Sprouty1 (Spry1), a growth factor signaling inhibitor as a regulator of marrow progenitor cells promoting osteoblast differentiation at the expense of adipocytes. Adipose tissue specific Spry1 expression in mice resulted in increased bone mass and reduced body fat while conditional knockout of Spry1 had the opposite effect with decreased bone and increased body fat. Because Spry1 suppresses normal fat development, we tested the hypothesis that Spry1 expression prevents high fat diet-induced obesity, bone loss, and associated lipid abnormalities and demonstrate that Spry1 has a long-term protective effect on mice fed a high caloric diet. We studied diet-induced obesity in mice with fatty acid binding promoter (aP2)-driven expression or conditional knockout of Spry1 in adipocytes. Phenotyping was performed by whole body dual-energy X-ray absorptiometry, microCT, histology and blood analysis. In conditional Spry1 null mice, high fat diet increased body fat by 40%, impaired glucose regulation, and led to liver steatosis. However, over-expression of Spry1 led to 35% lower body fat, reduced bone loss, and normal metabolic function compared to single transgenics. This protective phenotype was associated with decreased circulating insulin (70%) and leptin (54%) compared to controls on a high fat diet. Additionally, Spry1 expression decreased adipose tissue inflammation by 45%. We show that conditional Spry1 expression in adipose tissue protects against high fat diet-induced obesity and associated bone loss. PMID:22142492

Fat-specific protein 27 regulates storage of triacylglycerol

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Keller, P.; Petrie, J.T.; Rose, P. De

2008-01-01

FSP27 (fat-specific protein 27) is a member of the cell death-inducing DNA fragmentation factor-alpha-like effector (CIDE) family. Although Cidea and Cideb were initially characterized as activators of apoptosis, recent studies have demonstrated important metabolic roles for these proteins...... in several cell types without induction of adipocyte genes. Increased triacylglycerol is likely due to decreased beta-oxidation of nonesterified fatty acids. Altered flux of fatty acids into triacylglycerol may be a direct effect of FSP27 function, which is localized to lipid droplets in 293T cells and 3T3-L...... decreases with total fat mass but is not associated with measures of insulin resistance (e.g. homeostasis model assessment). Together, these data indicate that FSP27 binds to lipid droplets and regulates their enlargement Udgivelsesdato: 2008/5/23...

Association of carbohydrate and fat intake with metabolic syndrome.

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Kwon, Yu-Jin; Lee, Hye-Sun; Lee, Ji-Won

2018-04-01

In Asia, dietary pattern has been changed with increased intake of refined carbohydrates, sugar, and saturated fat, while the prevalence of metabolic syndrome (MetS) is on the rise. However, it remains unclear whether a high-carbohydrate or a high-fat diet is more metabolically harmful, and the optimal amount of carbohydrates and fat has not been determined. The aim of our study was to examine the role of carbohydrate and fat intake in MetS in a Korean population. Data were obtained from a large, population-based, cross-sectional study (6737 males and 8845 females). The subjects were divided into nine groups based on carbohydrate and fat proportion, and multiple logistic regression analysis was performed after adjusting for confounding variables. Regardless of fat intake, the risk of MetS significantly increased in males with higher carbohydrate proportions (of total energy intake). In females, the risk of MetS was significantly elevated only in those with both the highest carbohydrate proportion and lowest fat proportion. A high carbohydrate proportion was associated with a higher prevalence of MetS in males, and a high carbohydrate proportion combined with a low fat proportion was associated with MetS in females. Our results indicate that reduction of excessive carbohydrate intake paired with an adequate fat intake, taking into consideration optimal types of fat, is useful for MetS prevention. Longitudinal studies are needed to clarify the optimal types and amounts of carbohydrate and fat proportions as well as the mechanism underlying these relationships. Copyright © 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Common variants near MC4R in relation to body fat, body fat distribution, metabolic traits and energy expenditure

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Kring, Sofia Inez Iqbal; Holst, C; Toubro, Søren

2010-01-01

Common variants near melanocortin receptor 4 (MC4R) have been related to fatness and type 2 diabetes. We examined the associations of rs17782313 and rs17700633 in relation to body fat, body fat distribution, metabolic traits, weight development and energy expenditure.......Common variants near melanocortin receptor 4 (MC4R) have been related to fatness and type 2 diabetes. We examined the associations of rs17782313 and rs17700633 in relation to body fat, body fat distribution, metabolic traits, weight development and energy expenditure....

Android fat depot is more closely associated with metabolic syndrome than abdominal visceral fat in elderly people.

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Kang, Seon Mee; Yoon, Ji Won; Ahn, Hwa Young; Kim, So Yeon; Lee, Kyoung Ho; Shin, Hayley; Choi, Sung Hee; Park, Kyong Soo; Jang, Hak Chul; Lim, Soo

2011-01-01

Fat accumulation in android compartments may confer increased metabolic risk. The incremental utility of measuring regional fat deposition in association with metabolic syndrome (MS) has not been well described particularly in an elderly population. As part of the Korean Longitudinal Study on Health and Aging, which is a community-based cohort study of people aged more than 65 years, subjects (287 male, 75.9±8.6 years and 278 female, 76.0±8.8 years) with regional body composition data using Dual energy X-ray absorptiometry for android/gynoid area, computed tomography for visceral/subcutaneous adipose tissue (VAT/SAT), and cardiometabolic markers including adiponectin and high-sensitivity CRP were enrolled. We investigated the relationship between regional body composition and MS in multivariate regression models. Mean VAT and SAT area was 131.4±65.5 cm(2) and 126.9±55.2 cm(2) in men (P = 0.045) and 120.0±46.7 cm(2) and 211.8±65.9 cm(2) in women (Pandroid and gynoid fat amount was 1.8±0.8 kg and 2.5±0.8 kg in men and 2.0±0.6 kg and 3.3±0.8 kg in women, respectively (both Pandroid fat amount was strongly correlated with most metabolic risk factors compared to SAT or gynoid fat. Furthermore, android fat amount was significantly associated with clustering of MS components after adjustment for multiple parameters including age, gender, adiponectin, hsCRP, a surrogate marker of insulin resistance, whole body fat mass and VAT area. Our findings are consistent with the hypothesized role of android fat as a pathogenic fat depot in the MS. Measurement of android fat may provide a more complete understanding of metabolic risk associated with variations in fat distribution.

Tissue-specific expression of Sprouty1 in mice protects against high-fat diet-induced fat accumulation, bone loss and metabolic dysfunction.

Science.gov (United States)

Urs, Sumithra; Henderson, Terry; Le, Phuong; Rosen, Clifford J; Liaw, Lucy

2012-09-28

We recently characterised Sprouty1 (Spry1), a growth factor signalling inhibitor as a regulator of marrow progenitor cells promoting osteoblast differentiation at the expense of adipocytes. Adipose tissue-specific Spry1 expression in mice resulted in increased bone mass and reduced body fat, while conditional knockout of Spry1 had the opposite effect with decreased bone mass and increased body fat. Because Spry1 suppresses normal fat development, we tested the hypothesis that Spry1 expression prevents high-fat diet-induced obesity, bone loss and associated lipid abnormalities, and demonstrate that Spry1 has a long-term protective effect on mice fed a high-energy diet. We studied diet-induced obesity in mice with fatty acid binding promoter-driven expression or conditional knockout of Spry1 in adipocytes. Phenotyping was performed by whole-body dual-energy X-ray absorptiometry, microCT, histology and blood analysis. In conditional Spry1-null mice, a high-fat diet increased body fat by 40 %, impaired glucose regulation and led to liver steatosis. However, overexpression of Spry1 led to 35 % (P < 0·05) lower body fat, reduced bone loss and normal metabolic function compared with single transgenics. This protective phenotype was associated with decreased circulating insulin (70 %) and leptin (54 %; P < 0·005) compared with controls on a high-fat diet. Additionally, Spry1 expression decreased adipose tissue inflammation by 45 %. We show that conditional Spry1 expression in adipose tissue protects against high-fat diet-induced obesity and associated bone loss.

Insulin resistance and postreceptor changes of liver metabolism in fat-fed mice

DEFF Research Database (Denmark)

Hedeskov, Carl Jørgen; Capito, Kirsten; Hansen, Svend Erik

1992-01-01

Medicinsk biokemi, animal diabetes, insulin resistance, postreceptor defects, liver metabolism, high-fat diet......Medicinsk biokemi, animal diabetes, insulin resistance, postreceptor defects, liver metabolism, high-fat diet...

Responses to high-fat challenges varying in fat type in subjects with different metabolic risk phenotypes: a randomized trial.

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Susan J van Dijk

Full Text Available The ability of subjects to respond to nutritional challenges can reflect the flexibility of their biological system. Nutritional challenge tests could be used as an indicator of health status but more knowledge on metabolic and immune responses of different subjects to nutritional challenges is needed. The aim of this study was to compare the responses to high-fat challenges varying in fat type in subjects with different metabolic risk phenotypes.In a cross-over design 42 men (age 50-70 y consumed three high-fat shakes containing saturated fat (SFA, monounsaturated fat (MUFA or n-3 polyunsaturated (PUFA. Men were selected on BMI and health status (lean, obese or obese diabetic and phenotyped with MRI for adipose tissue distribution. Before and 2 and 4 h after shake consumption blood was drawn for measurement of expression of metabolic and inflammation-related genes in peripheral blood mononuclear cells (PBMCs, plasma triglycerides (TAG, glucose, insulin, cytokines and ex vivo PBMC immune response capacity. The MUFA and n-3 PUFA challenge, compared to the SFA challenge, induced higher changes in expression of inflammation genes MCP1 and IL1β in PBMCs. Obese and obese diabetic subjects had different PBMC gene expression and metabolic responses to high-fat challenges compared to lean subjects. The MUFA challenge induced the most pronounced TAG response, mainly in obese and obese diabetic subjects.The PBMC gene expression response and metabolic response to high-fat challenges were affected by fat type and metabolic risk phenotype. Based on our results we suggest using a MUFA challenge to reveal differences in response capacity of subjects.ClinicalTrials.gov NCT00977262.

[Effect of estradiol on food intake, glucose and fat metabolism in mice C57BL/6J with mutation yellow at the agouti locus].

Science.gov (United States)

Iakovleva, T V; Makarova, E N; Kazantseva, A Iu; Bazhan, N M

2012-05-01

Mutation yellow at the agouti locus in mice (A(y)/a-mice) causes the increase of food intake and development of obesity and type 2 diabetes. In A(y)/a-females the disturbances of glucose and fat metabolisms occur after puberty. We have assumed that the mutation yellow violates the regulatory effect of estradiol on glucose and fat metabolism in mice. We investigated the effects of ovariectomy and estradiol treatment on body weight, food intake, glucose tolerance, plasma levels of glucose, insulin and etherified fatty acids in A(y)/a-females. C57Bl/6J females, not carrying yellow mutation at the agouti locus (a/a-mice), were used as a control. The data suggest that the yellow mutation did not affect estradiol regulation of food intake and glucose blood levels after a night of fasting, but, apparently, prevented estradiol participation in the regulation of glucose and fat metabolisms in the muscle and fat tissues.

Abdominal fat and metabolic risk in obese children and adolescents.

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Revenga-Frauca, J; González-Gil, E M; Bueno-Lozano, G; De Miguel-Etayo, P; Velasco-Martínez, P; Rey-López, J P; Bueno-Lozano, O; Moreno, L A

2009-12-01

The aim of this study was to investigate fat distribution, mainly abdominal fat, and its relationship with metabolic risk variables in a group of 126 children and adolescents (60 males and 66 females) aged 5.0 to 14.9. According to IOTF criteria, 46 were classified as normal weight, 28 overweight and 52 obese. Weight, height, waist (WC) and hip circumferences were measured. The body mass index (BMI) was calculated. Total body fat, trunkal and abdominal fat were also assessed by dual energy x-ray absorptiometry (DXA). Glucose, insulin, HDL-Cholesterol, triglycerides (TG), ferritine, homocystein and C-reactive protein (CRP) were measured. Obesity status was related with insulin concentrations, CRP, TG and HDL. Obese patients had higher abdominal fat and higher CRP values than overweight and normal subjects. All markers of central body adiposity were related with insulin and lipid metabolism; however, they were not related with homocystein or ferritin. A simple anthropometric measurement, like waist circumference, seems to be a good predictor of the majority of the obesity related metabolic risk variables.

Regulation of brown adipocyte metabolism by myostatin/follistatin signaling

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Rajan eSingh

2014-10-01

Full Text Available Obesity develops from perturbations of cellular bioenergetics, when energy uptake exceeds energy expenditure, and represents a major risk factor for the development of type 2 diabetes, dyslipidemia, cardiovascular disease, cancer, and other conditions. Brown adipose tissue (BAT has long been known to dissipate energy as heat and contribute to energy expenditure, but its presence and physiological role in adult human physiology has been questioned for years. Recent demonstrations of metabolically active brown fat depots in adult humans have revolutionized current therapeutic approaches for obesity-related diseases. The balance between white adipose tissue (WAT and BAT affects the systemic energy balance and is widely believed to be the key determinant in the development of obesity and related metabolic diseases. Members of the transforming growth factor-beta (TGF-β superfamily play an important role in regulating overall energy homeostasis by modulation of brown adipocyte characteristics. Inactivation of TGF-β/Smad3/myostatin (Mst signaling promotes browning of white adipocytes, increases mitochondrial biogenesis and protects mice from diet-induced obesity, suggesting the need for development of a novel class of TGF-β/Mst antagonists for the treatment of obesity and related metabolic diseases. We recently described an important role of follistatin (Fst, a soluble glycoprotein that is known to bind and antagonize Mst actions, during brown fat differentiation and the regulation of cellular metabolism. Here we highlight various investigations performed using different in vitro and in vivo models to support the contention that targeting TGF-β/Mst signaling enhances brown adipocyte functions and regulates energy balance, reducing insulin resistance and curbing the development of obesity and diabetes.

Fat oxidation at rest predicts peak fat oxidation during exercise and metabolic phenotype in overweight men

DEFF Research Database (Denmark)

Rosenkilde, M; Nordby, P; Nielsen, L B

2010-01-01

OBJECTIVE: To elucidate if fat oxidation at rest predicts peak fat oxidation during exercise and/or metabolic phenotype in moderately overweight, sedentary men. DESIGN: Cross-sectional study.Subjects:We measured respiratory exchange ratio (RER) at rest in 44 moderately overweight, normotensive...... the International Diabetes Federation criteria, we found that there was a lower accumulation of metabolic risk factors in L-RER than in H-RER (1.6 vs 3.5, P=0.028), and no subjects in L-RER and four of eight subjects in H-RER had the metabolic syndrome. Resting RER was positively correlated with plasma...... triglycerides (Pexercise was positively correlated with plasma free fatty acid concentration at rest (Pexercise and a healthy metabolic...

Central nervous system regulation of intestinal lipid and lipoprotein metabolism.

Science.gov (United States)

Farr, Sarah; Taher, Jennifer; Adeli, Khosrow

2016-02-01

In response to nutrient availability, the small intestine and brain closely communicate to modulate energy homeostasis and metabolism. The gut-brain axis involves complex nutrient sensing mechanisms and an integration of neuronal and hormonal signaling. This review summarizes recent evidence implicating the gut-brain axis in regulating lipoprotein metabolism, with potential implications for the dyslipidemia of insulin resistant states. The intestine and brain possess distinct mechanisms for sensing lipid availability, which triggers subsequent regulation of feeding, glucose homeostasis, and adipose tissue metabolism. More recently, central receptors, neuropeptides, and gut hormones that communicate with the brain have been shown to modulate hepatic and intestinal lipoprotein metabolism via parasympathetic and sympathetic signaling. Gut-derived glucagon-like peptides appear to be particularly important in modulating the intestinal secretion of chylomicron particles via a novel brain-gut axis. Dysregulation of these pathways may contribute to postprandial diabetic dyslipidemia. Emerging evidence implicates the central and enteric nervous systems in controlling many aspects of lipid and lipoprotein metabolism. Bidirectional communication between the gut and brain involving neuronal pathways and gut peptides is critical for regulating feeding and metabolism, and forms a neuroendocrine circuit to modulate dietary fat absorption and intestinal production of atherogenic chylomicron particles.

PPAR-alpha dependent regulation of vanin-1 mediates hepatic lipid metabolism

NARCIS (Netherlands)

Diepen, van J.A.; Jansen, P.A.; Ballak, D.B.; Hijmans, A.; Hooiveld, G.J.E.J.; Rommelaere, S.; Kersten, A.H.; Stienstra, R.

2014-01-01

Background & Aims Peroxisome proliferator-activated receptor alpha (PPARa) is a key regulator of hepatic fat oxidation that serves as an energy source during starvation. Vanin-1 has been described as a putative PPARa target gene in liver, but its function in hepatic lipid metabolism is unknown.

Does caffeine alter muscle carbohydrate and fat metabolism during exercise?

DEFF Research Database (Denmark)

Graham, Terry E; Battram, Danielle S; Dela, Flemming

2008-01-01

and carbohydrate metabolism. While caffeine certainly mobilizes fatty acids from adipose tissue, rarely have measures of the respiratory exchange ratio indicated an increase in fat oxidation. However, this is a difficult measure to perform accurately during exercise, and small changes could be physiologically...... important. The few studies examining human muscle metabolism directly have also supported the fact that there is no change in fat or carbohydrate metabolism, but these usually have had a small sample size. We combined the data from muscle biopsy analyses of several similar studies to generate a sample size...

Association between pancreatic fat and incidence of metabolic syndrome: a 5-year Japanese cohort study.

Science.gov (United States)

Yamazaki, Hajime; Tauchi, Shinichi; Kimachi, Miho; Dohke, Mitsuru; Hanawa, Nagisa; Kodama, Yoshihisa; Katanuma, Akio; Yamamoto, Yosuke; Fukuma, Shingo; Fukuhara, Shunichi

2018-04-26

Previous cross-sectional studies showed that pancreatic fat was associated with metabolic syndrome. However, no longitudinal study has evaluated whether people with high pancreatic fat are likely to develop future metabolic syndrome. This study investigated the association between baseline pancreatic fat and metabolic syndrome incidence. In 2008-2009, 320 participants without metabolic syndrome underwent health checks, which included unenhanced computed tomography, and were followed up annually for 4-5 years. Baseline pancreatic fat amounts were evaluated using a histologically validated method that measured differences between pancreas and spleen attenuations on computed tomography. The participants were divided into low (reference), intermediate, and high pancreatic fat groups based on pancreas and spleen attenuation tertiles. Metabolic syndrome incidence was evaluated annually over a median follow-up period of 4.99 (interquartile range, 4.88-5.05) years, in accordance with the 2009 harmonized criteria. Risk ratios (RRs) for the association between baseline pancreatic fat amounts and metabolic syndrome incidence were estimated using Poisson regression models adjusted for age, sex, body mass index, liver fat, pre-metabolic syndrome, cigarette use, alcohol use, and physical activity. Metabolic syndrome incidence was 30.6% (98/320). Pancreatic fat was associated with an increased incidence of metabolic syndrome, based on a univariate analysis (RRs [95% confidence interval], 3.14 [1.74-5.67] and 3.96 [2.23-7.03] in the intermediate and high pancreatic fat groups, respectively). The association remained statistically significant in the multivariate analysis (RR [95% confidence interval], 2.04 [1.14-3.64] and 2.30 [1.28-4.14] for the same groups, respectively). Pancreatic fat predicts the future risk of metabolic syndrome. © 2018 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Diminished metabolic responses to centrally-administered apelin-13 in diet-induced obese rats fed a high-fat diet.

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Clarke, K J; Whitaker, K W; Reyes, T M

2009-02-01

The central administration of apelin, a recently identified adipokine, has been shown to affect food and water intake. The present study investigated whether body weight could affect an animal's response to apelin. The effects of centrally-administered apelin-13 on food and water intake, activity and metabolic rate were investigated in adult male diet-induced obese (DIO) rats fed either a high fat (32%) or control diet. Rats were administered i.c.v. apelin-13, 15-30 min prior to lights out, and food and water intake, activity and metabolic rate were assessed. Intracerebroventricular administration of apelin-13 decreased food and water intake and respiratory exchange ratio in DIO rats on the control diet, but had no effect in DIO rats on the high-fat diet. In an effort to identify potential central mechanisms explaining the observed physiological responses, the mRNA level of the apelin receptor, APJ, was examined in the hypothalamus. A high-fat diet induced an up-regulation of the expression of the receptor. Apelin induced a down-regulation of the receptor, but only in the DIO animals on the high-fat diet. In conclusion, we have demonstrated a diminished central nervous system response to apelin that is coincident with obesity.

Dietary Fat – Insulin Sensitivity and Molecular Substrate Metabolism

DEFF Research Database (Denmark)

Lundsgaard, Annemarie

metabolism in skeletal muscle. The high-fat diet was primarily comprised of unsaturated FA. We demonstrated in lean, healthy and moderately trained men that three days’ intake of 78 E% dietary fat coupled with 75% energy excess was sufficient to reduce whole-body insulin sensitivity by 17% and insulin...

Central serotonergic neurons activate and recruit thermogenic brown and beige fat and regulate glucose and lipid homeostasis

DEFF Research Database (Denmark)

McGlashon, Jacob M; Gorecki, Michelle C; Kozlowski, Amanda E

2015-01-01

Thermogenic brown and beige adipocytes convert chemical energy to heat by metabolizing glucose and lipids. Serotonin (5-HT) neurons in the CNS are essential for thermoregulation and accordingly may control metabolic activity of thermogenic fat. To test this, we generated mice in which the human...... adipose tissue (WAT). In parallel, blood glucose increased 3.5-fold, free fatty acids 13.4-fold, and triglycerides 6.5-fold. Similar BAT and beige fat defects occurred in Lmx1b(f/f)ePet1(Cre) mice in which 5-HT neurons fail to develop in utero. We conclude 5-HT neurons play a major role in regulating...

The obesity-induced transcriptional regulator TRIP-Br2 mediates visceral fat endoplasmic reticulum stress-induced inflammation.

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Qiang, Guifen; Kong, Hyerim Whang; Fang, Difeng; McCann, Maximilian; Yang, Xiuying; Du, Guanhua; Blüher, Matthias; Zhu, Jinfang; Liew, Chong Wee

2016-04-25

The intimate link between location of fat accumulation and metabolic disease risk and depot-specific differences is well established, but how these differences between depots are regulated at the molecular level remains largely unclear. Here we show that TRIP-Br2 mediates endoplasmic reticulum (ER) stress-induced inflammatory responses in visceral fat. Using in vitro, ex vivo and in vivo approaches, we demonstrate that obesity-induced circulating factors upregulate TRIP-Br2 specifically in visceral fat via the ER stress pathway. We find that ablation of TRIP-Br2 ameliorates both chemical and physiological ER stress-induced inflammatory and acute phase response in adipocytes, leading to lower circulating levels of inflammatory cytokines. Using promoter assays, as well as molecular and pharmacological experiments, we show that the transcription factor GATA3 is responsible for the ER stress-induced TRIP-Br2 expression in visceral fat. Taken together, our study identifies molecular regulators of inflammatory response in visceral fat that-given that these pathways are conserved in humans-might serve as potential therapeutic targets in obesity.

Deleted in breast cancer 1 limits adipose tissue fat accumulation and plays a key role in the development of metabolic syndrome phenotype.

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Escande, Carlos; Nin, Veronica; Pirtskhalava, Tamar; Chini, Claudia C S; Tchkonia, Tamar; Kirkland, James L; Chini, Eduardo N

2015-01-01

Obesity is often regarded as the primary cause of metabolic syndrome. However, many lines of evidence suggest that obesity may develop as a protective mechanism against tissue damage during caloric surplus and that it is only when the maximum fat accumulation capacity is reached and fatty acid spillover occurs into to peripheral tissues that metabolic diseases develop. In this regard, identifying the molecular mechanisms that modulate adipocyte fat accumulation and fatty acid spillover is imperative. Here we identify the deleted in breast cancer 1 (DBC1) protein as a key regulator of fat storage capacity of adipocytes. We found that knockout (KO) of DBC1 facilitated fat cell differentiation and lipid accumulation and increased fat storage capacity of adipocytes in vitro and in vivo. This effect resulted in a "healthy obesity" phenotype. DBC1 KO mice fed a high-fat diet, although obese, remained insulin sensitive, had lower free fatty acid in plasma, were protected against atherosclerosis and liver steatosis, and lived longer. We propose that DBC1 is part of the molecular machinery that regulates fat storage capacity in adipocytes and participates in the "turn-off" switch that limits adipocyte fat accumulation and leads to fat spillover into peripheral tissues, leading to the deleterious effects of caloric surplus. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Inflammation and ER Stress Regulate Branched-Chain Amino Acid Uptake and Metabolism in Adipocytes

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Burrill, Joel S.; Long, Eric K.; Reilly, Brian; Deng, Yingfeng; Armitage, Ian M.; Scherer, Philipp E.

2015-01-01

Inflammation plays a critical role in the pathology of obesity-linked insulin resistance and is mechanistically linked to the effects of macrophage-derived cytokines on adipocyte energy metabolism, particularly that of the mitochondrial branched-chain amino acid (BCAA) and tricarboxylic acid (TCA) pathways. To address the role of inflammation on energy metabolism in adipocytes, we used high fat-fed C57BL/6J mice and lean controls and measured the down-regulation of genes linked to BCAA and TCA cycle metabolism selectively in visceral but not in subcutaneous adipose tissue, brown fat, liver, or muscle. Using 3T3-L1 cells, TNFα, and other proinflammatory cytokine treatments reduced the expression of the genes linked to BCAA transport and oxidation. Consistent with this, [14C]-leucine uptake and conversion to triglycerides was markedly attenuated in TNFα-treated adipocytes, whereas the conversion to protein was relatively unaffected. Because inflammatory cytokines lead to the induction of endoplasmic reticulum stress, we evaluated the effects of tunicamycin or thapsigargin treatment of 3T3-L1 cells and measured a similar down-regulation in the BCAA/TCA cycle pathway. Moreover, transgenic mice overexpressing X-box binding protein 1 in adipocytes similarly down-regulated genes of BCAA and TCA metabolism in vivo. These results indicate that inflammation and endoplasmic reticulum stress attenuate lipogenesis in visceral adipose depots by down-regulating the BCAA/TCA metabolism pathway and are consistent with a model whereby the accumulation of serum BCAA in the obese insulin-resistant state is linked to adipose inflammation. PMID:25635940

Consequences of exchanging carbohydrates for proteins in the cholesterol metabolism of mice fed a high-fat diet.

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Frédéric Raymond

Full Text Available Consumption of low-carbohydrate, high-protein, high-fat diets lead to rapid weight loss but the cardioprotective effects of these diets have been questioned. We examined the impact of high-protein and high-fat diets on cholesterol metabolism by comparing the plasma cholesterol and the expression of cholesterol biosynthesis genes in the liver of mice fed a high-fat (HF diet that has a high (H or a low (L protein-to-carbohydrate (P/C ratio. H-P/C-HF feeding, compared with L-P/C-HF feeding, decreased plasma total cholesterol and increased HDL cholesterol concentrations at 4-wk. Interestingly, the expression of genes involved in hepatic steroid biosynthesis responded to an increased dietary P/C ratio by first down-regulation (2-d followed by later up-regulation at 4-wk, and the temporal gene expression patterns were connected to the putative activity of SREBF1 and 2. In contrast, Cyp7a1, the gene responsible for the conversion of cholesterol to bile acids, was consistently up-regulated in the H-P/C-HF liver regardless of feeding duration. Over expression of Cyp7a1 after 2-d and 4-wk H-P/C-HF feeding was connected to two unique sets of transcription regulators. At both time points, up-regulation of the Cyp7a1 gene could be explained by enhanced activations and reduced suppressions of multiple transcription regulators. In conclusion, we demonstrated that the hypocholesterolemic effect of H-P/C-HF feeding coincided with orchestrated changes of gene expressions in lipid metabolic pathways in the liver of mice. Based on these results, we hypothesize that the cholesterol lowering effect of high-protein feeding is associated with enhanced bile acid production but clinical validation is warranted. (246 words.

Consequences of exchanging carbohydrates for proteins in the cholesterol metabolism of mice fed a high-fat diet.

Science.gov (United States)

Raymond, Frédéric; Wang, Long; Moser, Mireille; Metairon, Sylviane; Mansourian, Robert; Zwahlen, Marie-Camille; Kussmann, Martin; Fuerholz, Andreas; Macé, Katherine; Chou, Chieh Jason

2012-01-01

Consumption of low-carbohydrate, high-protein, high-fat diets lead to rapid weight loss but the cardioprotective effects of these diets have been questioned. We examined the impact of high-protein and high-fat diets on cholesterol metabolism by comparing the plasma cholesterol and the expression of cholesterol biosynthesis genes in the liver of mice fed a high-fat (HF) diet that has a high (H) or a low (L) protein-to-carbohydrate (P/C) ratio. H-P/C-HF feeding, compared with L-P/C-HF feeding, decreased plasma total cholesterol and increased HDL cholesterol concentrations at 4-wk. Interestingly, the expression of genes involved in hepatic steroid biosynthesis responded to an increased dietary P/C ratio by first down-regulation (2-d) followed by later up-regulation at 4-wk, and the temporal gene expression patterns were connected to the putative activity of SREBF1 and 2. In contrast, Cyp7a1, the gene responsible for the conversion of cholesterol to bile acids, was consistently up-regulated in the H-P/C-HF liver regardless of feeding duration. Over expression of Cyp7a1 after 2-d and 4-wk H-P/C-HF feeding was connected to two unique sets of transcription regulators. At both time points, up-regulation of the Cyp7a1 gene could be explained by enhanced activations and reduced suppressions of multiple transcription regulators. In conclusion, we demonstrated that the hypocholesterolemic effect of H-P/C-HF feeding coincided with orchestrated changes of gene expressions in lipid metabolic pathways in the liver of mice. Based on these results, we hypothesize that the cholesterol lowering effect of high-protein feeding is associated with enhanced bile acid production but clinical validation is warranted. (246 words).

CTRP3 attenuates diet-induced hepatic steatosis by regulating triglyceride metabolism.

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Peterson, Jonathan M; Seldin, Marcus M; Wei, Zhikui; Aja, Susan; Wong, G William

2013-08-01

CTRP3 is a secreted plasma protein of the C1q family that helps regulate hepatic gluconeogenesis and is downregulated in a diet-induced obese state. However, the role of CTRP3 in regulating lipid metabolism has not been established. Here, we used a transgenic mouse model to address the potential function of CTRP3 in ameliorating high-fat diet-induced metabolic stress. Both transgenic and wild-type mice fed a high-fat diet showed similar body weight gain, food intake, and energy expenditure. Despite similar adiposity to wild-type mice upon diet-induced obesity (DIO), CTRP3 transgenic mice were strikingly resistant to the development of hepatic steatosis, had reduced serum TNF-α levels, and demonstrated a modest improvement in systemic insulin sensitivity. Additionally, reduced hepatic triglyceride levels were due to decreased expression of enzymes (GPAT, AGPAT, and DGAT) involved in triglyceride synthesis. Importantly, short-term daily administration of recombinant CTRP3 to DIO mice for 5 days was sufficient to improve the fatty liver phenotype, evident as reduced hepatic triglyceride content and expression of triglyceride synthesis genes. Consistent with a direct effect on liver cells, recombinant CTRP3 treatment reduced fatty acid synthesis and neutral lipid accumulation in cultured rat H4IIE hepatocytes. Together, these results establish a novel role for CTRP3 hormone in regulating hepatic lipid metabolism and highlight its protective function and therapeutic potential in attenuating hepatic steatosis.

Insulin Action in Brain Regulates Systemic Metabolism and Brain Function

OpenAIRE

Kleinridders, Andr?; Ferris, Heather A.; Cai, Weikang; Kahn, C. Ronald

2014-01-01

Insulin receptors, as well as IGF-1 receptors and their postreceptor signaling partners, are distributed throughout the brain. Insulin acts on these receptors to modulate peripheral metabolism, including regulation of appetite, reproductive function, body temperature, white fat mass, hepatic glucose output, and response to hypoglycemia. Insulin signaling also modulates neurotransmitter channel activity, brain cholesterol synthesis, and mitochondrial function. Disruption of insulin action in t...

Dietary fat source affects metabolism of fatty acids in pigs as evaluated by altered expression of lipogenic genes in liver and adipose tissues

DEFF Research Database (Denmark)

Duran-Montge, P; Theil, Peter Kappel; Lauridsen, Charlotte

2009-01-01

Little is known about pig gene expressions related to dietary fatty acids (FAs) and most work have been conducted in rodents. The aim of this study was to investigate how dietary fats regulate fat metabolism of pigs in different tissues. Fifty-six crossbred gilts (62 ± 5.2 kg BW) were fed one of ...

Regulation of lipid metabolism by energy availability: a role for the central nervous system.

Science.gov (United States)

Nogueiras, R; López, M; Diéguez, C

2010-03-01

The central nervous system (CNS) is crucial in the regulation of energy homeostasis. Many neuroanatomical studies have shown that the white adipose tissue (WAT) is innervated by the sympathetic nervous system, which plays a critical role in adipocyte lipid metabolism. Therefore, there are currently numerous reports indicating that signals from the CNS control the amount of fat by modulating the storage or oxidation of fatty acids. Importantly, some CNS pathways regulate adipocyte metabolism independently of food intake, suggesting that some signals possess alternative mechanisms to regulate energy homeostasis. In this review, we mainly focus on how neuronal circuits within the hypothalamus, such as leptin- ghrelin-and resistin-responsive neurons, as well as melanocortins, neuropeptide Y, and the cannabinoid system exert their actions on lipid metabolism in peripheral tissues such as WAT, liver or muscle. Dissecting the complicated interactions between peripheral signals and neuronal circuits regulating lipid metabolism might open new avenues for the development of new therapies preventing and treating obesity and its associated cardiometabolic sequelae.

Cyclin G Functions as a Positive Regulator of Growth and Metabolism in Drosophila.

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Patrick Fischer

2015-08-01

Full Text Available In multicellular organisms, growth and proliferation is adjusted to nutritional conditions by a complex signaling network. The Insulin receptor/target of rapamycin (InR/TOR signaling cascade plays a pivotal role in nutrient dependent growth regulation in Drosophila and mammals alike. Here we identify Cyclin G (CycG as a regulator of growth and metabolism in Drosophila. CycG mutants have a reduced body size and weight and show signs of starvation accompanied by a disturbed fat metabolism. InR/TOR signaling activity is impaired in cycG mutants, combined with a reduced phosphorylation status of the kinase Akt1 and the downstream factors S6-kinase and eukaryotic translation initiation factor 4E binding protein (4E-BP. Moreover, the expression and accumulation of Drosophila insulin like peptides (dILPs is disturbed in cycG mutant brains. Using a reporter assay, we show that the activity of one of the first effectors of InR signaling, Phosphoinositide 3-kinase (PI3K92E, is unaffected in cycG mutants. However, the metabolic defects and weight loss in cycG mutants were rescued by overexpression of Akt1 specifically in the fat body and by mutants in widerborst (wdb, the B'-subunit of the phosphatase PP2A, known to downregulate Akt1 by dephosphorylation. Together, our data suggest that CycG acts at the level of Akt1 to regulate growth and metabolism via PP2A in Drosophila.

Glucagon-insulin interaction on fat cell metabolism using c14 glucose

International Nuclear Information System (INIS)

Zewail, M.A.; Nielsen, J.H.

1984-01-01

Glucagon is known to stimulate the lipolysis in isolated fat cells from young rats, but not in fat cells from old heavy rate (Manganiello 1972). Insulin is known to counteract the lipolytic effect and to stimulate the synthesis of fatty acids from glucose. However, little is known about the interaction between the two hormones on the glucose metabolism. Experiments based on the use of various inhibitors of lipolysis have however, clearly shown that glucagon can also stimulate the entry and overall oxidation of glucose by mechanism which is distinct from its lipolysis stimulating mechanism (M. Blecher et al. 1969). Fat cells from old heavy rats are known to be less responsive to both the lipogenic action of insulin and the lipolytic action of glucagon than fat cells from young lean rats (E.G. Hansen, Nielsen and Gliemann, 1974). The aim of the present study was to see how glucagon affects glucose metabolism in fat cells, and whether this effect was dependent on the lipolytic action of glucagon

Effects of α-Galactooligosaccharides from Chickpeas on High-Fat-Diet-Induced Metabolic Syndrome in Mice.

Science.gov (United States)

Dai, Zhuqing; Lyu, Wanyong; Xie, Minhao; Yuan, Qingxia; Ye, Hong; Hu, Bing; Zhou, Li; Zeng, Xiaoxiong

2017-04-19

The gut microbiota has the ability to modulate host energy homeostasis, which may regulate metabolic disorders. Functional oligosaccharide may positively regulate the intestinal microbiota. Therefore, effects of α-galactooligosaccharides (α-GOS) from chickpea on high-fat-diet (HFD)-induced metabolic syndrome and gut bacterial dysbiosis were investigated. After 6 weeks of intervention, HFD led to significant increases in levels of blood glucose, total cholesterol, triglyceride, glycated serum protein, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol of mice compared to normal-chow-fed mice. Meanwhile, all of the α-GOS-treated groups significantly decreased above parameters compared to the HFD group. HFD could significantly decrease the content of all bacteria, especially Bacteroides (9.82 ± 0.09 versus 10.3 ± 0.10; p bacterial ecosystem in a positive way.

Hepatic fat accumulation and regulation of FAT/CD36: an effect of hepatic irradiation

Science.gov (United States)

Martius, Gesa; Alwahsh, Salamah Mohammad; Rave-Fränk, Margret; Hess, Clemens Friedrich; Christiansen, Hans; Ramadori, Giuliano; Malik, Ihtzaz Ahmed

2014-01-01

Irradiation is known to induce inflammation and affect fat metabolic pathways. The current study investigates hepatic fat accumulation and fatty acid transportation in a rat model of single dose liver irradiation (25-Gy). Rat livers were selectively irradiated in-vivo (25-Gy), sham-irradiated rats served as controls. Hepatic lipids were studied by colorimetric assays in liver and serum. Intracellular lipids, protein and mRNA were studied by Nile red staining, immunohistology, Western Blot analysis and RT-PCR in liver, respectively. Changes in FAT/CD36 expression were studied in-vitro in a human monocyte cell line U937 after irradiation in presence or absence of infliximab (IFX). Nile Red staining of liver cryosections showed a quick (12-48 h) increase in fat droplets. Accordingly, hepatic triglycerides (TG) and free fatty acids (FFA) were elevated. An early increase (3-6 h) in the serum level of HDL-C, TG and cholesterol was measured after single dose irradiation followed by a decrease thereafter. Furthermore, expression of the fat transporter protein FAT/CD36 was increased, immunohistochemistry revealed basolateral and cytoplasmic expression in hepatocytes. Moreover, apolipoprotein-B100, -C3 and enzymes (acetyl-CoA carboxylase, lipoprotein-lipase, carnitine-palmitoyltransferase, malonyl-CoA-decarboxylase) involved in fat metabolism were induced at 12-24 h. Early activation of the NFkβ pathway (IκBα) by TNF-α was seen, followed by a significant elevation of serum markers for liver damage (AST and GLDH). TNF-α blockage by anti-TNF-α in cell culture (U937) prevented the increase of FAT/CD36 caused by irradiation. Selective liver irradiation is a model for rapid induction of steatosis hepatis and fat accumulation could be triggered by irradiation-induced inflammatory mediators (e.g. TNF-α). PMID:25197426

Effects of puerarin on lipid accumulation and metabolism in high-fat diet-fed mice.

Directory of Open Access Journals (Sweden)

Guodong Zheng

Full Text Available In order to investigate the mechanisms by which puerarin from kudzu root extract regulates lipid metabolism, fifty mice were randomly assigned to five groups: normal diet, high-fat diet (HFD, and HFD containing 0.2%, 0.4% or 0.8% puerarin for 12 weeks. Body weight, intraperitioneal adipose tissue (IPAT weight, serum biochemical parameters, and hepatic and feces lipids were measured. Activity and mRNA and protein expressions of hepatic lipid metabolism-related enzymes were analyzed. Compared with HFD, 0.4% and 0.8% puerarin significantly decreased body and IPAT weight. There was a significant decrease in the serum and hepatic concentrations of total cholesterol, triglycerides and leptin in mice fed the 0.4% and 0.8% puerarin diets compared with HFD. Fatty acid synthase activity was suppressed in mice fed the 0.4% and 0.8% puerarin diets, while the activities of AMP-activated protein kinase (AMPK, carnitine acyltransferase (CAT and hormone-sensitive lipase (HSL were increased. mRNA expression of peroxisome proliferator-activated receptor γ 2 (PPARγ 2 was down-regulated in liver of mice fed the 0.8% diet compared with HFD, while mRNA expression of CAT and HSL was considerably up-regulated by 0.4% and 0.8% puerarin diets. The protein expression of PPARγ2 in liver was decreased and those of p-AMPK, HSL and p-HSL were increased in mice fed 0.4% and 0.8% puerarin diets. These results suggest that > 0.4% puerarin influenced the activity, mRNA and protein levels of hepatic lipid metabolism-related enzymes, decreasing serum and liver lipids, body weight gain and fat accumulation. Puerarin might be beneficial to prevent lifestyle-related diseases.

RNA-Seq Analysis of Abdominal Fat in Genetically Fat and Lean Chickens Highlights a Divergence in Expression of Genes Controlling Adiposity, Hemostasis, and Lipid Metabolism

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Resnyk, Christopher W.; Chen, Chuming; Huang, Hongzhan; Wu, Cathy H.; Simon, Jean; Le Bihan-Duval, Elisabeth; Duclos, Michel J.; Cogburn, Larry A.

2015-01-01

Genetic selection for enhanced growth rate in meat-type chickens (Gallus domesticus) is usually accompanied by excessive adiposity, which has negative impacts on both feed efficiency and carcass quality. Enhanced visceral fatness and several unique features of avian metabolism (i.e., fasting hyperglycemia and insulin insensitivity) mimic overt symptoms of obesity and related metabolic disorders in humans. Elucidation of the genetic and endocrine factors that contribute to excessive visceral fatness in chickens could also advance our understanding of human metabolic diseases. Here, RNA sequencing was used to examine differential gene expression in abdominal fat of genetically fat and lean chickens, which exhibit a 2.8-fold divergence in visceral fatness at 7 wk. Ingenuity Pathway Analysis revealed that many of 1687 differentially expressed genes are associated with hemostasis, endocrine function and metabolic syndrome in mammals. Among the highest expressed genes in abdominal fat, across both genotypes, were 25 differentially expressed genes associated with de novo synthesis and metabolism of lipids. Over-expression of numerous adipogenic and lipogenic genes in the FL chickens suggests that in situ lipogenesis in chickens could make a more substantial contribution to expansion of visceral fat mass than previously recognized. Distinguishing features of the abdominal fat transcriptome in lean chickens were high abundance of multiple hemostatic and vasoactive factors, transporters, and ectopic expression of several hormones/receptors, which could control local vasomotor tone and proteolytic processing of adipokines, hemostatic factors and novel endocrine factors. Over-expression of several thrombogenic genes in abdominal fat of lean chickens is quite opposite to the pro-thrombotic state found in obese humans. Clearly, divergent genetic selection for an extreme (2.5–2.8-fold) difference in visceral fatness provokes a number of novel regulatory responses that govern

Newborn body fat: associations with maternal metabolic state and placental size.

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Camilla M Friis

Full Text Available BACKGROUND: Neonatal body composition has implications for the health of the newborn both in short and long term perspective. The objective of the current study was first to explore the association between maternal BMI and metabolic parameters associated with BMI and neonatal percentage body fat and to determine to which extent any associations were modified if adjusting for placental weight. Secondly, we examined the relations between maternal metabolic parameters associated with BMI and placental weight. METHODS: The present work was performed in a subcohort (n = 207 of the STORK study, an observational, prospective study on the determinants of fetal growth and birthweight in healthy pregnancies at Oslo University Hospital, Norway. Fasting glucose, insulin, triglycerides, free fatty acids, HDL- and total cholesterol were measured at week 30-32. Newborn body composition was determined by Dual-Energy X-Ray Absorptiometry (DXA. Placenta was weighed at birth. Linear regression models were used with newborn fat percentage and placental weight as main outcomes. RESULTS: Maternal BMI, fasting glucose and gestational age were independently associated with neonatal fat percentage. However, if placental weight was introduced as a covariate, only placental weight and gestational age remained significant. In the univariate model, the determinants of placenta weight included BMI, insulin, triglycerides, total- and HDL-cholesterol (negatively, gestational weight gain and parity. In the multivariable model, BMI, total cholesterol HDL-cholesterol, gestational weight gain and parity remained independent covariates. CONCLUSION: Maternal BMI and fasting glucose were independently associated with newborn percentage fat. This effect disappeared by introducing placental weight as a covariate. Several metabolic factors associated with maternal BMI were associated with placental weight, but not with neonatal body fat. Our findings are consistent with a concept

MiR-27a suppresses triglyceride accumulation and affects gene mRNA expression associated with fat metabolism in dairy goat mammary gland epithelial cells.

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Lin, Xian-Zi; Luo, Jun; Zhang, Li-Ping; Wang, Wei; Shi, Heng-Bo; Zhu, Jiang-Jiang

2013-05-25

MicroRNAs (miRNAs), a well-defined group of small RNAs containing about 22 nucleotides, participate in various biological metabolic processes. miR-27a is a miRNA that is known to regulate fat synthesis and differentiation in preadipocyte cells. However, little is known regarding the role that miR-27a plays in regulating goat milk fat synthesis. In this study, we determined the miR-27a expression profile in goat mammary gland and found that miR-27a expression was correlated with the lactation cycle. Additionally, prolactin promoted miR-27a expression in goat mammary gland epithelial cells. Further functional analysis showed that over-expression of miR-27a down-regulated triglyceride accumulation and decreased the ratio of unsaturated/saturated fatty acid in mammary gland epithelial cells. miR-27a also significantly affected mRNA expression related to milk fat metabolism. Specifically, over-expression of miR-27a reduced gene mRNA expression associated with triglyceride synthesis by suppressing PPARγ protein levels. This study provides the first experimental evidence that miR-27a regulates triglyceride synthesis in goat mammary gland epithelial cells and improves our understanding about the importance of miRNAs in milk fat synthesis. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Trans fats in New Zealand: time for labelling regulations?

Science.gov (United States)

Gladding, Patrick; Benatar, Jocelyne R

2007-11-09

Trans fats (trans fatty acids) are commonly used for deep frying in restaurants and in the fast food, snack food, fried food, and baked goods industries, often to extend the shelf life of foods. However they are widely considered to be harmful to health. Trans fats were banned in New York City restaurants from 1 July 2007, and there is growing vocal opposition to trans fats in the European Union. Denmark became the first country, in March 2003, to introduce laws regulating the content of trans fats in food (maximum of 2% of edible fats and oils). What are trans fats, what harm do they cause, and should New Zealand also consider imposing mandatory regulations on their use in food? This article explores the issues.

Dietary salecan reverts partially the metabolic gene expressions and NMR-based metabolomic profiles from high-fat-diet-induced obese rats.

Science.gov (United States)

Sun, Qi; Li, Minghui; Yang, Xiao; Xu, Xi; Wang, Junsong; Zhang, Jianfa

2017-09-01

Previous studies suggest that dietary salecan (a water-soluble β-glucan) effectively reduces high-fat-diet-induced adiposity through disturbing bile-acid-promoted emulsification in mice. However, the effects of salecan on metabolic genes and metabolites involved in lipid accumulation are mostly unknown. Here, we confirmed that dietary 3% and 6% salecan for 4 weeks markedly decreased fat accumulation in liver and adipose tissue in high-fat-diet rats, displaying a decrease in mRNA levels of SREBP1-C, FAS, SCD1 and ACC1 involved in de novo lipogenesis and a reduction of levels of GPAT1, DGAT1 and DGAT2 related to triglyceride synthesis. Dietary salecan also increased the mRNA levels of PPARα and CYP7A1, which are related to fatty acid oxidation and cholesterol decomposition, respectively. In the 1 H nuclear magnetic resonance metabolomic analysis, both the serum and liver metabolite profiles differed among the control groups, and the metabolic profiles of the salecan groups were shifted toward that of the low-fat-diet group. Metabolites analysis showed that salecan significantly increased hepatic glutathione and betaine levels which are related to regulation of cellular reactive oxygen species. These data demonstrate that dietary salecan not only disturbed fat digestion and absorption but also influenced lipid accumulation and metabolism in diet-induced obesity. Copyright © 2017 Elsevier Inc. All rights reserved.

Dopamine Signaling Regulates Fat Content through β-Oxidation in Caenorhabditis elegans

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Barros, Alexandre Guimarães de Almeida; Bridi, Jessika Cristina; de Souza, Bruno Rezende; de Castro Júnior, Célio; de Lima Torres, Karen Cecília; Malard, Leandro; Jorio, Ado; de Miranda, Débora Marques; Ashrafi, Kaveh; Romano-Silva, Marco Aurélio

2014-01-01

The regulation of energy balance involves an intricate interplay between neural mechanisms that respond to internal and external cues of energy demand and food availability. Compelling data have implicated the neurotransmitter dopamine as an important part of body weight regulation. However, the precise mechanisms through which dopamine regulates energy homeostasis remain poorly understood. Here, we investigate mechanisms through which dopamine modulates energy storage. We showed that dopamine signaling regulates fat reservoirs in Caenorhabditis elegans. We found that the fat reducing effects of dopamine were dependent on dopaminergic receptors and a set of fat oxidation enzymes. Our findings reveal an ancient role for dopaminergic regulation of fat and suggest that dopamine signaling elicits this outcome through cascades that ultimately mobilize peripheral fat depots. PMID:24465759

IL-6 selectively stimulates fat metabolism in human skeletal muscle

DEFF Research Database (Denmark)

Wolsk, Emil; Mygind, Helene; Grøndahl, Thomas S

2010-01-01

and glucose metabolism and signaling of both adipose tissue and skeletal muscle. Eight healthy postabsorptive males were infused with either rhIL-6 or saline for 4 h, eliciting IL-6 levels of ~40 and ~1 pg/ml, respectively. Systemic, skeletal muscle, and adipose tissue fat and glucose metabolism was assessed......Interleukin (IL)-6 is chronically elevated in type 2 diabetes but also during exercise. However, the exact metabolic role, and hence the physiological significance, has not been elucidated. The objective of this study was to investigate the in vivo effect of recombinant human (rh) IL-6 on human fat...... before, during, and 2 h after cessation of the infusion. Glucose metabolism was unaffected by rhIL-6. In contrast, rhIL-6 increased systemic fatty acid oxidation approximately twofold after 60 min, and it remained elevated even 2 h after the infusion. The increase in oxidation was followed by an increase...

IL-6 selectively stimulates fat metabolism in human skeletal muscle

DEFF Research Database (Denmark)

Wolsk, Emil; Mygind, Helene; Grøndahl, Thomas S

2010-01-01

and glucose metabolism and signaling of both adipose tissue and skeletal muscle. Eight healthy postabsorptive males were infused with either rhIL-6 or saline for 4 h, eliciting IL-6 levels of ∼40 and ∼1 pg/ml, respectively. Systemic, skeletal muscle, and adipose tissue fat and glucose metabolism was assessed......Interleukin (IL)-6 is chronically elevated in type 2 diabetes but also during exercise. However, the exact metabolic role, and hence the physiological significance, has not been elucidated. The objective of this study was to investigate the in vivo effect of recombinant human (rh) IL-6 on human fat...... before, during, and 2 h after cessation of the infusion. Glucose metabolism was unaffected by rhIL-6. In contrast, rhIL-6 increased systemic fatty acid oxidation approximately twofold after 60 min, and it remained elevated even 2 h after the infusion. The increase in oxidation was followed by an increase...

Regulation of Lipid and Glucose Metabolism by Phosphatidylcholine Transfer Protein

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Kang, Hye Won; Wei, Jie; Cohen, David E.

2010-01-01

Phosphatidylcholine transfer protein (PC-TP, a.k.a. StARD2) binds phosphatidylcholines and catalyzes their intermembrane transfer and exchange in vitro. The structure of PC-TP comprises a hydrophobic pocket and a well-defined head-group binding site, and its gene expression is regulated by peroxisome proliferator activated receptor α. Recent studies have revealed key regulatory roles for PC-TP in lipid and glucose metabolism. Notably, Pctp−/− mice are sensitized to insulin action and exhibit more efficient brown fat-mediated thermogenesis. PC-TP appears to limit access of fatty acids to mitochondria by stimulating the activity of thioesterase superfamily member 2, a newly characterized long-chain fatty acyl-CoA thioesterase. Because PC-TP discriminates among phosphatidylcholines within lipid bilayers, it may function as a sensor that links metabolic regulation to membrane composition. PMID:20338778

Myeloid-specific deletion of NOX2 prevents the metabolic and neurologic consequences of high fat diet.

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Jennifer K Pepping

Full Text Available High fat diet-induced obesity is associated with inflammatory and oxidative signaling in macrophages that likely participates in metabolic and physiologic impairment. One key factor that could drive pathologic changes in macrophages is the pro-inflammatory, pro-oxidant enzyme NADPH oxidase. However, NADPH oxidase is a pleiotropic enzyme with both pathologic and physiologic functions, ruling out indiscriminant NADPH oxidase inhibition as a viable therapy. To determine if targeted inhibition of monocyte/macrophage NADPH oxidase could mitigate obesity pathology, we generated mice that lack the NADPH oxidase catalytic subunit NOX2 in myeloid lineage cells. C57Bl/6 control (NOX2-FL and myeloid-deficient NOX2 (mNOX2-KO mice were given high fat diet for 16 weeks, and subject to comprehensive metabolic, behavioral, and biochemical analyses. Data show that mNOX2-KO mice had lower body weight, delayed adiposity, attenuated visceral inflammation, and decreased macrophage infiltration and cell injury in visceral adipose relative to control NOX2-FL mice. Moreover, the effects of high fat diet on glucose regulation and circulating lipids were attenuated in mNOX2-KO mice. Finally, memory was impaired and markers of brain injury increased in NOX2-FL, but not mNOX2-KO mice. Collectively, these data indicate that NOX2 signaling in macrophages participates in the pathogenesis of obesity, and reinforce a key role for macrophage inflammation in diet-induced metabolic and neurologic decline. Development of macrophage/immune-specific NOX-based therapies could thus potentially be used to preserve metabolic and neurologic function in the context of obesity.

The Interplay Between Fat Mass and Fat Distribution as Determinants of the Metabolic Syndrome Is Sex-Dependent.

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Lind, Lars; Ärnlöv, Johan; Lampa, Erik

2017-09-01

Fat mass and fat distribution are major determinants of the metabolic syndrome (MetS), but the interplay between them has not been thoroughly investigated. In addition, fat mass and fat distribution are generally different in men than in women. We aimed to determine whether the interplay between fat mass and fat distribution regarding MetS and its components is sex-dependent using data from the large-scale population-based sample EpiHealth. Occurrence of MetS and its components was determined together with fat mass by bioimpedance in 19,094 participants in the EpiHealth sample [mean age 61 years (SD 8.5), 56% females]. MetS was defined by the NCEP/ATPIII-criteria. MetS prevalence was 23.0%. Fat mass (percent of body weight) was more strongly related to MetS (and the number of MetS components) in men than in women (P distribution on the fat mass versus MetS-relationship is stronger in women.

Phloretin Prevents High-Fat Diet-Induced Obesity and Improves Metabolic Homeostasis.

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Alsanea, Sary; Gao, Mingming; Liu, Dexi

2017-05-01

Reactive oxygen species generated as a by-product in metabolism play a central role in the development of obesity and obesity-related metabolic complications. The objective of the current study is to explore the possibility to block obesity and improve metabolic homeostasis via phloretin, a natural antioxidant product from apple tree leaves and Manchurian apricot. Both preventive and therapeutic activities of phloretin were assessed using a high-fat diet-induced obesity mouse model. Phloretin was injected intraperitoneally twice weekly into regular and obese mice fed a high-fat diet. The effects of phloretin treatment on body weight and composition, fat content in the liver, glucose and lipid metabolism, and insulin resistance were monitored and compared to the control animals. Phloretin treatment significantly blocks high-fat diet-induced weight gain but did not induce weight loss in obese animals. Phloretin improved glucose homeostasis and insulin sensitivity and alleviated hepatic lipid accumulation. RT-PCR analysis showed that phloretin treatment suppresses expression of macrophage markers (F4/80 and Cd68) and pro-inflammatory genes (Mcp-1 and Ccr2) and enhances adiponectin gene expression in white adipose tissue. In addition, phloretin treatment elevated the expression of fatty acid oxidation genes such as carnitine palmitoyltransferase 1a and 1b (Cpt1a and Cpt1b) and reduced expression of monocyte chemoattractant protein-1 (Mcp-1), de novo lipogenesis transcriptional factor peroxisome proliferator-activated receptor-γ 2 (Pparγ2), and its target monoacylglycerol O-acyltransferase (Mgat-1) genes. These results provide direct evidence to support a possible use of phloretin for mitigation of obesity and maintenance of metabolic homeostasis.

Nuclear magnetic resonance studies of metabolic regulation

International Nuclear Information System (INIS)

Sillerud, L.O.; Han, C.H.; Whaley, T.W.

1983-01-01

Nuclear magnetic resonance (NMR) techniques for the detection of the metabolic transformations of biological compounds labeled with stable isotopes, particularly carbon-13 have been explored. We have studied adipose tissue in the intact rat, the exteriorized epididymal fat pad, and the isolated adipocyte. Triacylglycerol metabolism in adipose tissue is regulated by lipogenic factors (insulin, corticosterone, thyroxine, and growth hormone) and lipolytic factors (glucagon and catecholamines). The synthesis of triglyceride from 5.5 mM glucose was stimulated by about 4-fold by 10 nM insulin. Triglyceride synthesis from glucose in the presence of insulin occurred at a rate of 330 nmol/hr/10 6 cells. Since the NMR signals from free and esterified fatty acids and glycerol are distinct, we could directly measure the rate of hormone-stimulated lipolysis. Epinephrine (10 μM) gave a lipolytic rate of 0.30 μmol/hr/10 6 cells as monitored by free-glycerol appearance in the medium. 13 C NMR provides a superior method for the measurement of triglyceride metabolism since it directly measures the changes in the substrates and products in situ

Effects of abhydrolase domain containing 5 gene (ABHD5) expression and variations on chicken fat metabolism.

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Ouyang, Hongjia; Liu, Qing; Xu, Jiguo; Zeng, Fang; Pang, Xiaolin; Jebessa, Endashaw; Liang, Shaodong; Nie, Qinghua; Zhang, Xiquan

2016-01-01

Abhydrolase domain containing 5 gene (ABHD5), also known as comparative gene identification 58 (CGI-58), is a member of the α/β-hydrolase family as a protein cofactor of ATGL stimulating its triacylglycerol hydrolase activity. In this study, we aim to characterize the expression and variations of ABHD5 and to study their functions in chicken fat metabolism. We compared the ABHD5 expression level in various tissues and under different nutrition conditions, identified the variations of ABHD5, and associated them with production traits in an F2 resource population of chickens. Overexpression analysis with two different genotypes and siRNA interfering analysis of ABHD5 were performed in chicken preadipocytes. Chicken ABDH5 was expressed widely and most predominantly in adipose tissue. Five SNPs of the ABHD5 gene were identified and genotyped in the F2 resource population. The c.490C > T SNP was associated with subcutaneous fat thickness (P  C SNP was also associated with chicken body weight (P chicken preadipocytes, overexpression of wild type ABDH5 did not affect the mRNA level of ATGL (adipose triglyceride lipase) but markedly decreased (P chickens with a high fat diet. These results suggest that expression and variations of ABHD5 may affect fat metabolism through regulating the activity of ATGL in chickens. © 2015 Poultry Science Association Inc.

Oral insulin improves metabolic parameters in high fat diet fed rats

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LEANDRO C. LIPINSKI

2017-08-01

Full Text Available ABSTRACT Introduction/Aim: The gut has shown to have a pivotal role on the pathophysiology of metabolic disease. Food stimulation of distal intestinal segments promotes enterohormones secretion influencing insulin metabolism. In diabetic rats, oral insulin has potential to change intestinal epithelium behavior. This macromolecule promotes positive effects on laboratorial metabolic parameters and decreases diabetic intestinal hypertrophy. This study aims to test if oral insulin can influence metabolic parameters and intestinal weight in obese non-diabetic rats. Methods: Twelve weeks old Wistar rats were divided in 3 groups: control (CTRL standard chow group; high fat diet low carbohydrates group (HFD and HFD plus daily oral 20U insulin gavage (HFD+INS. Weight and food consumption were weekly obtained. After eight weeks, fasting blood samples were collected for laboratorial analysis. After euthanasia gut samples were isolated. Results: Rat oral insulin treatment decreased body weight gain (p<0,001, fasting glucose and triglycerides serum levels (p<0,05 an increased intestinal weight of distal ileum (P<0,05. Animal submitted to high fat diet presented higher levels of HOMA-IR although significant difference to CT was not achieved. HOMA-beta were significantly higher (p<0.05 in HFD+INS. Visceral fat was 10% lower in HFD+INS but the difference was not significant. Conclusions: In non-diabetic obese rats, oral insulin improves metabolic malfunction associated to rescue of beta-cell activity.

Effects of angiotensin (1-7 on nephrosis of the mice with metabolic syndrome induced by high-salt and high-fat diet

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Nan ZHU

2013-11-01

mice. Valsartan, an angiotensin Ⅱ receptor blocker, can alleviate the metabolic abnormality caused by the high-salt and high-fat diet, and the protection mechanism may be related to up-regulation of angiotensin (1-7. DOI: 10.11855/j.issn.0577-7402.2013.10.001

Opposing Fat Metabolism Pathways Triggered by a Single Gene

OpenAIRE

Gilst, Marc R. Van; Hadjivassiliou, Haralambos; Jolly, Amber; Yamamoto, Keith R

2005-01-01

Mammalian nuclear hormone receptors (NHRs), such as liver X receptor, farnesoid X receptor, and peroxisome proliferator-activated receptors (PPARs), precisely control energy metabolism. Consequently, these receptors are important targets for the treatment of metabolic diseases, including diabetes and obesity. A thorough understanding of NHR fat regulatory networks has been limited, however, by a lack of genetically tractable experimental systems. Here we show that deletion of the Caenorhabdit...

Abdominal fat analyzed by DEXA scan reflects visceral body fat and improves the phenotype description and the assessment of metabolic risk in mice

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Chen, Weiyi; Wilson, Jenny L.; Khaksari, Mohammad; Cowley, Michael A.

2012-01-01

Clinical studies have demonstrated a strong relationship between visceral fat content and metabolic diseases, such as type 2 diabetes and liver steatosis. Obese mouse models are an excellent tool to study metabolic diseases; however, there are limited methods for the noninvasive measurement of fat distribution in mice. Although micromagnetic resonance imaging and microcomputed tomography are the “gold standards” in the measurement of fat distribution, more economical and accessible methods are required. Dual energy X-ray absorptiometry (DEXA) is an effective method in characterizing fat content; however, it cannot discriminate between visceral and subcutaneous fat depots. We demonstrate that an evaluation of abdominal fat content measured by DEXA through the selection of one localized abdominal area strongly correlates with visceral fat content in C57BL/6J mice. We found that DEXA is able to measure fat pad volume ex vivo with high accuracy; however, the measurement of visceral fat in vivo shows an overestimation caused by subcutaneous tissue interference. The overestimation is almost constant for a wide range of values, and thus it is possible to correct the data for a more accurate estimation of visceral fat content. We demonstrate the utility of this technique in characterizing phenotypes of several obese mouse models (ob/ob, db/db, MC4R-KO, and DIO) and evaluating the effect of treatments on visceral fat content in longitudinal studies. Additionally, we also establish abdominal obesity as a potential biomarker for metabolic abnormalities (liver fat accumulation, insulin resistance/diabetes) in mice, similar to that described in humans. PMID:22761161

Natural compounds regulate energy metabolism by the modulating the activity of lipid-sensing nuclear receptors.

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Goto, Tsuyoshi; Kim, Young-Il; Takahashi, Nobuyuki; Kawada, Teruo

2013-01-01

Obesity causes excess fat accumulation in various tissues, most notoriously in the adipose tissue, along with other insulin-responsive organs such as skeletal muscle and the liver, which predisposes an individual to the development of metabolic abnormalities. The molecular mechanisms underlying obesity-induced metabolic abnormalities have not been completely elucidated; however, in recent years, the search for therapies to prevent the development of obesity and obesity-associated metabolic disorders has increased. It is known that several nuclear receptors, when activated by specific ligands, regulate carbohydrate and lipid metabolism at the transcriptional level. The expression of lipid metabolism-related enzymes is directly regulated by the activity of various nuclear receptors via their interaction with specific response elements in promoters of those genes. Many natural compounds act as ligands of nuclear receptors and regulate carbohydrate and lipid metabolism by regulating the activities of these nuclear receptors. In this review, we describe our current knowledge of obesity, the role of lipid-sensing nuclear receptors in energy metabolism, and several examples of food factors that act as agonists or antagonists of nuclear receptors, which may be useful for the management of obesity and the accompanying energy metabolism abnormalities. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Prenatal Metformin Exposure in Mice Programs the Metabolic Phenotype of the Offspring during a High Fat Diet at Adulthood

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Salomäki, Henriikka; Vähätalo, Laura H.; Laurila, Kirsti; Jäppinen, Norma T.; Penttinen, Anna-Maija; Ailanen, Liisa; Ilyasizadeh, Juan; Pesonen, Ullamari; Koulu, Markku

2013-01-01

Aims The antidiabetic drug metformin is currently used prior and during pregnancy for polycystic ovary syndrome, as well as during gestational diabetes mellitus. We investigated the effects of prenatal metformin exposure on the metabolic phenotype of the offspring during adulthood in mice. Methods Metformin (300 mg/kg) or vehicle was administered orally to dams on regular diet from the embryonic day E0.5 to E17.5. Gene expression profiles in liver and brain were analysed from 4-day old offspring by microarray. Body weight development and several metabolic parameters of offspring were monitored both during regular diet (RD-phase) and high fat diet (HFD-phase). At the end of the study, two doses of metformin or vehicle were given acutely to mice at the age of 20 weeks, and Insig-1 and GLUT4 mRNA expressions in liver and fat tissue were analysed using qRT-PCR. Results Metformin exposed fetuses were lighter at E18.5. There was no effect of metformin on the maternal body weight development or food intake. Metformin exposed offspring gained more body weight and mesenteric fat during the HFD-phase. The male offspring also had impaired glucose tolerance and elevated fasting glucose during the HFD-phase. Moreover, the expression of GLUT4 mRNA was down-regulated in epididymal fat in male offspring prenatally exposed to metformin. Based on the microarray and subsequent qRT-PCR analyses, the expression of Insig-1 was changed in the liver of neonatal mice exposed to metformin prenatally. Furthermore, metformin up-regulated the expression of Insig-1 later in development. Gene set enrichment analysis based on preliminary microarray data identified several differentially enriched pathways both in control and metformin exposed mice. Conclusions The present study shows that prenatal metformin exposure causes long-term programming effects on the metabolic phenotype during high fat diet in mice. This should be taken into consideration when using metformin as a therapeutic agent during

Prenatal metformin exposure in mice programs the metabolic phenotype of the offspring during a high fat diet at adulthood.

Directory of Open Access Journals (Sweden)

Henriikka Salomäki

Full Text Available AIMS: The antidiabetic drug metformin is currently used prior and during pregnancy for polycystic ovary syndrome, as well as during gestational diabetes mellitus. We investigated the effects of prenatal metformin exposure on the metabolic phenotype of the offspring during adulthood in mice. METHODS: Metformin (300 mg/kg or vehicle was administered orally to dams on regular diet from the embryonic day E0.5 to E17.5. Gene expression profiles in liver and brain were analysed from 4-day old offspring by microarray. Body weight development and several metabolic parameters of offspring were monitored both during regular diet (RD-phase and high fat diet (HFD-phase. At the end of the study, two doses of metformin or vehicle were given acutely to mice at the age of 20 weeks, and Insig-1 and GLUT4 mRNA expressions in liver and fat tissue were analysed using qRT-PCR. RESULTS: Metformin exposed fetuses were lighter at E18.5. There was no effect of metformin on the maternal body weight development or food intake. Metformin exposed offspring gained more body weight and mesenteric fat during the HFD-phase. The male offspring also had impaired glucose tolerance and elevated fasting glucose during the HFD-phase. Moreover, the expression of GLUT4 mRNA was down-regulated in epididymal fat in male offspring prenatally exposed to metformin. Based on the microarray and subsequent qRT-PCR analyses, the expression of Insig-1 was changed in the liver of neonatal mice exposed to metformin prenatally. Furthermore, metformin up-regulated the expression of Insig-1 later in development. Gene set enrichment analysis based on preliminary microarray data identified several differentially enriched pathways both in control and metformin exposed mice. CONCLUSIONS: The present study shows that prenatal metformin exposure causes long-term programming effects on the metabolic phenotype during high fat diet in mice. This should be taken into consideration when using metformin as a

Early metabolic adaptation in C57BL/6 mice resistant to high fat diet induced weight gain involves an activation of mitochondrial oxidative pathways.

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Boulangé, Claire L; Claus, Sandrine P; Chou, Chieh J; Collino, Sebastiano; Montoliu, Ivan; Kochhar, Sunil; Holmes, Elaine; Rezzi, Serge; Nicholson, Jeremy K; Dumas, Marc E; Martin, François-Pierre J

2013-04-05

We investigated the short-term (7 days) and long-term (60 days) metabolic effect of high fat diet induced obesity (DIO) and weight gain in isogenic C57BL/6 mice and examined the specific metabolic differentiation between mice that were either strong-responders (SR), or non-responders (NR) to weight gain. Mice (n = 80) were fed a standard chow diet for 7 days prior to randomization into a high-fat (HF) (n = 56) or a low-fat (LF) (n = 24) diet group. The (1)H NMR urinary metabolic profiles of LF and HF mice were recorded 7 and 60 days after the diet switch. On the basis of the body weight gain (BWG) distribution of HF group, we identified NR mice (n = 10) and SR mice (n = 14) to DIO. Compared with LF, HF feeding increased urinary excretion of glycine conjugates of β-oxidation intermediate (hexanoylglycine), branched chain amino acid (BCAA) catabolism intermediates (isovalerylglycine, α-keto-β-methylvalerate and α-ketoisovalerate) and end-products of nicotinamide adenine dinucleotide (NAD) metabolism (N1-methyl-2-pyridone-5-carboxamide, N1-methyl-4-pyridone-3-carboxamide) suggesting up-regulation of mitochondrial oxidative pathways. In the HF group, NR mice excreted relatively more hexanoylglycine, isovalerylglycine, and fewer tricarboxylic acid (TCA) cycle intermediate (succinate) in comparison to SR mice. Thus, subtle regulation of ketogenic pathways in DIO may alleviate the saturation of the TCA cycle and mitochondrial oxidative metabolism.

Maternal high-fat diet intensifies the metabolic response to stress in male rat offspring

OpenAIRE

Karbaschi, Roxana; Zardooz, Homeira; Khodagholi, Fariba; Dargahi, Leila; Salimi, Mina; Rashidi, FatemehSadat

2017-01-01

Background The mother?s consumption of high-fat food can affect glucose metabolism and the hypothalamic?pituitary?adrenal axis responsiveness in the offspring and potentially affect the metabolic responses to stress as well. This study examines the effect of maternal high-fat diet on the expression of pancreatic glucose transporter 2 and the secretion of insulin in response to stress in offspring. Methods Female rats were randomly divided into normal and high-fat diet groups and were fed in a...

Effect of Diet, Insulin and Exercise on the Regulation of Carbohydrate Metabolism in Health and Type 1 Diabetes

OpenAIRE

Chokkalingam, Kamalakkannan

2007-01-01

The objective of this thesis was to further the understanding of the effect of diet, insulin and exercise on the regulation of carbohydrate metabolism in health and type 1 diabetes. Three studies were undertaken in both non-diabetic healthy volunteers and patients with type 1 diabetes. The first study determined the influence of high fat diet on biochemical and molecular regulators of whole body and muscle metabolism in healthy volunteers. The second study examined the influence of insulin on...

Increased susceptibility of post-weaning rats on high-fat diet to metabolic syndrome

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Hong Sheng Cheng

2017-11-01

Full Text Available The present study aimed to examine the effects of the types of high-calorie diets (high-fat and high-fat-high-sucrose diets and two different developmental stages (post-weaning and young adult on the induction of metabolic syndrome. Male, post-weaning and adult (3- and 8-week old, respectively Sprague Dawley rats were given control, high-fat (60% kcal, and high-fat-high-sucrose (60% kcal fat + 30% sucrose water diets for eight weeks (n = 6 to 7 per group. Physical, biochemical, and transcriptional changes as well as liver histology were noted. Post-weaning rats had higher weight gain, abdominal fat mass, fasting glucose, high density lipoprotein cholesterol, faster hypertension onset, but lower circulating advanced glycation end products compared to adult rats. This is accompanied by upregulation of peroxisome proliferator-activated receptor (PPAR α and γ in the liver and receptor for advanced glycation end products (RAGE in the visceral adipose tissue. Post-weaning rats on high-fat diet manifested all phenotypes of metabolic syndrome and increased hepatic steatosis, which are linked to increased hepatic and adipocyte PPARγ expression. Adult rats on high-fat-high-sucrose diet merely became obese and hypertensive within the same treatment duration. Thus, it is more effective and less time-consuming to induce metabolic syndrome in male post-weaning rats with high-fat diet compared to young adult rats. As male rats were selectively included into the study, the results may not be generalisable to all post-weaning rats and further investigation on female rats is required.

Fat metabolism during exercise in patients with McArdle disease

DEFF Research Database (Denmark)

Ørngreen, M C; Jeppesen, T D; Andersen, S Tvede

2009-01-01

carbohydrate oxidation was lower, during exercise in patients with McArdle disease vs healthy controls. We found augmented fat oxidation with the onset of a second wind, but further increases in FFA availability, as exercise continued, did not result in further increases in FAO. CONCLUSION: These results......OBJECTIVE: It is known that muscle phosphorylase deficiency restricts carbohydrate utilization, but the implications for muscle fat metabolism have not been studied. We questioned whether patients with McArdle disease can compensate for the blocked muscle glycogen breakdown by enhancing fat...... indicate that patients with McArdle disease have exaggerated fat oxidation during prolonged, low-intensity exercise and that increased fat oxidation may be an important mechanism of the spontaneous second wind. The fact that increasing availability of free fatty acids with more prolonged exercise did...

Low trans structured fat from flaxseed oil improves plasma and hepatic lipid metabolism in apo E(-/-) mice.

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Cho, Yun-Young; Kwon, Eun-Young; Kim, Hye-Jin; Park, Yong-Bok; Lee, Ki-Teak; Park, Taesun; Choi, Myung-Sook

2009-07-01

The objective of this study was to explicate the effects of feeding low trans structured fat from flaxseed oil (LF) on plasma and hepatic lipid metabolism involved in apo E(-/-) mice. The animals were fed a commercial shortening (CS), commercial low trans fat (CL) and LF diet based on AIN-76 diet (10% fat) for 12 weeks. LF supplementation exerted a significant suppression in hepatic lipid accumulation with the concomitant decrease in liver weight. The LF significantly lowered plasma total cholesterol and free fatty acid whereas it significantly increased HDL-C concentration and the HDL-C/total-C ratio compared to the CS group. Reduction of hepatic lipid levels in the LF group was related with the suppression of hepatic enzyme activities for fatty acid and triglyceride synthesis, and cholesterol regulating enzyme activity compared to the CS and CL groups. Accordingly, low trans structured fat from flaxseed oil is highly effective for improving hyperlipidemia and hepatic lipid accumulation in apo E(-/-) mice.

The Lin28/let-7 axis regulates glucose metabolism

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Zhu, Hao; Shyh-Chang, Ng; Segrè, Ayellet V.; Shinoda, Gen; Shah, Samar P.; Einhorn, William S.; Takeuchi, Ayumu; Engreitz, Jesse M.; Hagan, John P.; Kharas, Michael G; Urbach, Achia; Thornton, James E.; Triboulet, Robinson; Gregory, Richard I.; Altshuler, David; Daley, George Q.

2012-01-01

SUMMARY The let-7 tumor suppressor microRNAs are known for their regulation of oncogenes, while the RNA-binding proteins Lin28a/b promote malignancy by blocking let-7 biogenesis. In studies of the Lin28/let-7 pathway, we discovered unexpected roles in regulating metabolism. When overexpressed in mice, both Lin28a and LIN28B promoted an insulin-sensitized state that resisted high fat diet-induced diabetes, whereas muscle-specific loss of Lin28a and overexpression of let-7 resulted in insulin resistance and impaired glucose tolerance. These phenomena occurred in part through let-7-mediated repression of multiple components of the insulin-PI3K-mTOR pathway, including IGF1R, INSR, and IRS2. The mTOR inhibitor rapamycin abrogated the enhanced glucose uptake and insulin-sensitivity conferred by Lin28a in vitro and in vivo. In addition, we found that let-7 targets were enriched for genes that contain SNPs associated with type 2 diabetes and fasting glucose in human genome-wide association studies. These data establish the Lin28/let-7 pathway as a central regulator of mammalian glucose metabolism. PMID:21962509

Effect of diosgenin on metabolic dysfunction: Role of ERβ in the regulation of PPARγ

Energy Technology Data Exchange (ETDEWEB)

Wang, Xin, E-mail: xinwang@fmmu.edu.cn [Department of Toxicology, Shaanxi Key Lab of Free Radical Biology and Medicine, the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi' an 710032 (China); Liu, Jun [Department of Orthopedics, Lanzhou General Hospital of PLA, South Binhe Road, No. 333, Lanzhou 730050 (China); Long, Zi; Sun, Quangui [The First Student Brigade, Fourth Military Medical University, Xi' an, Shaanxi, 710032 (China); Liu, Ying; Wang, Lele; Zhang, Xiaodi [Department of Toxicology, Shaanxi Key Lab of Free Radical Biology and Medicine, the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi' an 710032 (China); Hai, Chunxu, E-mail: cx-hai@fmmu.edu.cn [Department of Toxicology, Shaanxi Key Lab of Free Radical Biology and Medicine, the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi' an 710032 (China)

2015-12-01

The present study was designed to investigate the effect of diosgenin (DSG) on metabolic dysfunction and to elucidate the possible molecular mechanisms. High fat (HF) diet-fed mice and 3T3-L1 preadipocytes was used to evaluate the effect of DSG. We showed that DSG attenuated metabolic dysfunction in HF diet-fed mice, as evidenced by reduction of blood glucose level and improvement of glucose and insulin intolerance. DSG ameliorated oxidative stress, reduced body weight, fat pads, and systematic lipid profiles and attenuated lipid accumulation. DSG inhibited 3T3-L1 adipocyte differentiation and reduced adipocyte size through regulating key factors. DSG inhibited PPARγ and its target gene expression both in differentiated 3T3-L1 adipocytes and fat tissues in HF diet-fed mice. Overexpression of PPARγ suppressed DSG-inhibited adipocyte differentiation. DSG significantly increased nuclear expression of ERβ. Inhibition of ERβ significantly suppressed DSG-exerted suppression of adipocyte differentiation and PPARγ expression. In response to DSG stimulation, ERβ bound with RXRα and dissociated RXRα from PPARγ, leading to the reduction of transcriptional activity of PPARγ. These data provide new insight into the mechanisms underlying the inhibitory effect of DSG on adipocyte differentiation and demonstrate that ERβ-exerted regulation of PPARγ expression and activity is critical for DSG-inhibited adipocyte differentiation. - Highlights: • Diosgenin (DSG) attenuated metabolic dysfunction in high fat (HF) diet-fed mice. • DSG reduced oxidative stress and lipid accumulation in HF diet-fed mice. • DSG inhibited 3T3-L1 adipocyte differentiation and reduced adipocyte size. • DSG induced the binding of ERβ with RXRα. • DSG-induced activation of ERβ dissociated RXRα from PPARγ and reduced PPARγ activity.

Effect of diosgenin on metabolic dysfunction: Role of ERβ in the regulation of PPARγ

International Nuclear Information System (INIS)

Wang, Xin; Liu, Jun; Long, Zi; Sun, Quangui; Liu, Ying; Wang, Lele; Zhang, Xiaodi; Hai, Chunxu

2015-01-01

The present study was designed to investigate the effect of diosgenin (DSG) on metabolic dysfunction and to elucidate the possible molecular mechanisms. High fat (HF) diet-fed mice and 3T3-L1 preadipocytes was used to evaluate the effect of DSG. We showed that DSG attenuated metabolic dysfunction in HF diet-fed mice, as evidenced by reduction of blood glucose level and improvement of glucose and insulin intolerance. DSG ameliorated oxidative stress, reduced body weight, fat pads, and systematic lipid profiles and attenuated lipid accumulation. DSG inhibited 3T3-L1 adipocyte differentiation and reduced adipocyte size through regulating key factors. DSG inhibited PPARγ and its target gene expression both in differentiated 3T3-L1 adipocytes and fat tissues in HF diet-fed mice. Overexpression of PPARγ suppressed DSG-inhibited adipocyte differentiation. DSG significantly increased nuclear expression of ERβ. Inhibition of ERβ significantly suppressed DSG-exerted suppression of adipocyte differentiation and PPARγ expression. In response to DSG stimulation, ERβ bound with RXRα and dissociated RXRα from PPARγ, leading to the reduction of transcriptional activity of PPARγ. These data provide new insight into the mechanisms underlying the inhibitory effect of DSG on adipocyte differentiation and demonstrate that ERβ-exerted regulation of PPARγ expression and activity is critical for DSG-inhibited adipocyte differentiation. - Highlights: • Diosgenin (DSG) attenuated metabolic dysfunction in high fat (HF) diet-fed mice. • DSG reduced oxidative stress and lipid accumulation in HF diet-fed mice. • DSG inhibited 3T3-L1 adipocyte differentiation and reduced adipocyte size. • DSG induced the binding of ERβ with RXRα. • DSG-induced activation of ERβ dissociated RXRα from PPARγ and reduced PPARγ activity.

Intra-abdominal fat measurement by ultrasonography: association with anthropometry and metabolic syndrome in adolescents.

Science.gov (United States)

Novais, Rommel L R; Café, Ana Carolina C; Morais, Aisha A; Bila, Wendell C; Santos, Gilson D da S; Lopes, Carlos Alexandre de O; Belo, Vinícius S; Romano, Márcia Christina C; Lamounier, Joel A

2018-04-27

To associate intra-abdominal fat thickness measured by ultrasonography to the factors related to metabolic syndrome and to determine cutoff points of intra-abdominal fat measurement associated with a greater chance of metabolic syndrome in adolescents. This was a cross-sectional study, with 423 adolescents from public schools. Intra-abdominal fat was measured by ultrasonography. Anthropometric data were collected, and biochemical analyses were performed. Intra-abdominal fat was measured by ultrasonography, showing a statistically significant association with the diagnosis of metabolic syndrome (p=0.037), body mass index (p<0.001), elevated triglyceride levels (p=0.012), decreased plasma HDL levels (p=0.034), and increased systemic blood pressure values (p=0.023). Cutoff values of intra-abdominal fat thickness measurements were calculated by ultrasound to estimate the individuals most likely to develop metabolic syndrome. In the logistic regression models, the cutoff values that showed the highest association with metabolic syndrome in males were 4.50, 5.35, 5.46, 6.24, and 6.50cm for the ages of 14, 15, 16, 17, and 18/19 years, respectively. In the female gender, the cutoff values defined for the same age groups were 4.46, 4.55, 4.45, 4.90, and 6.46cm. In an overall analysis using the ROC curve, without gender and age stratification, the cut-off of 3.67cm showed good sensitivity, but low specificity. Ultrasonography is a useful method to estimate intra-abdominal adipose tissue in adolescents, which is associated with the main factors related to obesity and metabolic syndrome. Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Elucidation of molecular mechanisms of physiological variations between bovine subcutaneous and visceral fat depots under different nutritional regimes.

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Romao, Josue Moura; Jin, Weiwu; He, Maolong; McAllister, Tim; Guan, Le Luo

2013-01-01

Adipose tissue plays a critical role in energy homeostasis and metabolism. There is sparse understanding of the molecular regulation at the protein level of bovine adipose tissues, especially within different fat depots under different nutritional regimes. The objective of this study was to analyze the differences in protein expression between bovine subcutaneous and visceral fat depots in steers fed different diets and to identify the potential regulatory molecular mechanisms of protein expression. Subcutaneous and visceral fat tissues were collected from 16 British-continental steers (15.5 month old) fed a high-fat diet (7.1% fat, n=8) or a control diet (2.7% fat, n=8). Protein expression was profiled using label free quantification LC-MS/MS and expression of selected transcripts was evaluated using qRT-PCR. A total of 682 proteins were characterized and quantified with fat depot having more impact on protein expression, altering the level of 51.0% of the detected proteins, whereas diet affected only 5.3%. Functional analysis revealed that energy production and lipid metabolism were among the main functions associated with differentially expressed proteins between fat depots, with visceral fat being more metabolically active than subcutaneous fat as proteins associated with lipid and energy metabolism were upregulated. The expression of several proteins was significantly correlated to subcutaneous fat thickness and adipocyte size, indicating their potential as adiposity markers. A poor correlation (r=0.245) was observed between mRNA and protein levels for 9 genes, indicating that many proteins may be subjected to post-transcriptional regulation. A total of 8 miRNAs were predicted to regulate more than 20% of lipid metabolism proteins differentially expressed between fat depots, suggesting that miRNAs play a role in adipose tissue regulation. Our results show that proteomic changes support the distinct metabolic and physiological characteristics observed between

Systems biology of adipose tissue metabolism: regulation of growth, signaling and inflammation.

Science.gov (United States)

Manteiga, Sara; Choi, Kyungoh; Jayaraman, Arul; Lee, Kyongbum

2013-01-01

Adipose tissue (AT) depots actively regulate whole body energy homeostasis by orchestrating complex communications with other physiological systems as well as within the tissue. Adipocytes readily respond to hormonal and nutritional inputs to store excess nutrients as intracellular lipids or mobilize the stored fat for utilization. Co-ordinated regulation of metabolic pathways balancing uptake, esterification, and hydrolysis of lipids is accomplished through positive and negative feedback interactions of regulatory hubs comprising several pleiotropic protein kinases and nuclear receptors. Metabolic regulation in adipocytes encompasses biogenesis and remodeling of uniquely large lipid droplets (LDs). The regulatory hubs also function as energy and nutrient sensors, and integrate metabolic regulation with intercellular signaling. Over-nutrition causes hypertrophic expansion of adipocytes, which, through incompletely understood mechanisms, initiates a cascade of metabolic and signaling events leading to tissue remodeling and immune cell recruitment. Macrophage activation and polarization toward a pro-inflammatory phenotype drives a self-reinforcing cycle of pro-inflammatory signals in the AT, establishing an inflammatory state. Sustained inflammation accelerates lipolysis and elevates free fatty acids in circulation, which robustly correlates with development of obesity-related diseases. The adipose regulatory network coupling metabolism, growth, and signaling of multiple cell types is exceedingly complex. While components of the regulatory network have been individually studied in exquisite detail, systems approaches have rarely been utilized to comprehensively assess the relative engagements of the components. Thus, need and opportunity exist to develop quantitative models of metabolic and signaling networks to achieve a more complete understanding of AT biology in both health and disease. Copyright © 2013 Wiley Periodicals, Inc.

Central serotonergic neurons activate and recruit thermogenic brown and beige fat and regulate glucose and lipid homeostasis.

Science.gov (United States)

McGlashon, Jacob M; Gorecki, Michelle C; Kozlowski, Amanda E; Thirnbeck, Caitlin K; Markan, Kathleen R; Leslie, Kirstie L; Kotas, Maya E; Potthoff, Matthew J; Richerson, George B; Gillum, Matthew P

2015-05-05

Thermogenic brown and beige adipocytes convert chemical energy to heat by metabolizing glucose and lipids. Serotonin (5-HT) neurons in the CNS are essential for thermoregulation and accordingly may control metabolic activity of thermogenic fat. To test this, we generated mice in which the human diphtheria toxin receptor (DTR) was selectively expressed in central 5-HT neurons. Treatment with diphtheria toxin (DT) eliminated 5-HT neurons and caused loss of thermoregulation, brown adipose tissue (BAT) steatosis, and a >50% decrease in uncoupling protein 1 (Ucp1) expression in BAT and inguinal white adipose tissue (WAT). In parallel, blood glucose increased 3.5-fold, free fatty acids 13.4-fold, and triglycerides 6.5-fold. Similar BAT and beige fat defects occurred in Lmx1b(f/f)ePet1(Cre) mice in which 5-HT neurons fail to develop in utero. We conclude 5-HT neurons play a major role in regulating glucose and lipid homeostasis, in part through recruitment and metabolic activation of brown and beige adipocytes. Copyright © 2015 Elsevier Inc. All rights reserved.

Interplay between FGF21 and insulin action in the liver regulates metabolism

DEFF Research Database (Denmark)

Emanuelli, Brice; Vienberg, Sara G; Smyth, Graham

2014-01-01

gluconeogenesis in these animals. Improvements in blood sugar were due in part to increased glucose uptake in brown fat, browning of white fat, and overall increased energy expenditure. These effects were preserved even after removal of the main interscapular brown fat pad. In contrast to its retained effects...... of insulin action in the liver by increasing energy metabolism via activation of brown fat and browning of white fat, but intact liver insulin action is required for FGF21 to control hepatic lipid metabolism....

Effect of dietary fat on hepatic liver X receptor expression in P-glycoprotein deficient mice: implications for cholesterol metabolism

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Lee Stephen D

2008-06-01

Full Text Available Abstract Pgp (P-glycoprotein, MDR1, ABCB1 is an energy-dependent drug efflux pump that is a member of the ATP-binding cassette (ABC family of proteins. Preliminary studies have reported that nonspecific inhibitors of Pgp affect synthesis and esterification of cholesterol, putatively by blocking trafficking of cholesterol from the plasma membrane to the endoplasmic reticulum, and that relative increases in Pgp within a given cell type are associated with increased accumulation of cholesterol. Several key efflux proteins involved in the cholesterol metabolic pathway are transcriptionally regulated by the nuclear hormone liver X receptor (LXR. Therefore, to examine the interplay between P-glycoprotein and the cholesterol metabolic pathway, we utilized a high fat, normal cholesterol diet to upregulate LXRα without affecting dietary cholesterol. Our research has demonstrated that mice lacking in P-glycoprotein do not exhibit alterations in hepatic total cholesterol storage, circulating plasma total cholesterol levels, or total cholesterol concentration in the bile when compared to control animals on either a normal (25% calories from dietary fat or high fat (45% calories from dietary fat diet. However, p-glycoprotein deficient mice (Mdr1a-/-/1b-/- exhibit increased hepatic LXRα protein expression and an elevation in fecal cholesterol concentration when compared to controls.

Insulin action in brain regulates systemic metabolism and brain function.

Science.gov (United States)

Kleinridders, André; Ferris, Heather A; Cai, Weikang; Kahn, C Ronald

2014-07-01

Insulin receptors, as well as IGF-1 receptors and their postreceptor signaling partners, are distributed throughout the brain. Insulin acts on these receptors to modulate peripheral metabolism, including regulation of appetite, reproductive function, body temperature, white fat mass, hepatic glucose output, and response to hypoglycemia. Insulin signaling also modulates neurotransmitter channel activity, brain cholesterol synthesis, and mitochondrial function. Disruption of insulin action in the brain leads to impairment of neuronal function and synaptogenesis. In addition, insulin signaling modulates phosphorylation of tau protein, an early component in the development of Alzheimer disease. Thus, alterations in insulin action in the brain can contribute to metabolic syndrome, and the development of mood disorders and neurodegenerative diseases. © 2014 by the American Diabetes Association.

PPARγ isoforms differentially regulate metabolic networks to mediate mouse prostatic epithelial differentiation.

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Strand, D W; Jiang, M; Murphy, T A; Yi, Y; Konvinse, K C; Franco, O E; Wang, Y; Young, J D; Hayward, S W

2012-08-09

Recent observations indicate prostatic diseases are comorbidities of systemic metabolic dysfunction. These discoveries revealed fundamental questions regarding the nature of prostate metabolism. We previously showed that prostate-specific ablation of PPARγ in mice resulted in tumorigenesis and active autophagy. Here, we demonstrate control of overlapping and distinct aspects of prostate epithelial metabolism by ectopic expression of individual PPARγ isoforms in PPARγ knockout prostate epithelial cells. Expression and activation of either PPARγ 1 or 2 reduced de novo lipogenesis and oxidative stress and mediated a switch from glucose to fatty acid oxidation through regulation of genes including Pdk4, Fabp4, Lpl, Acot1 and Cd36. Differential effects of PPARγ isoforms included decreased basal cell differentiation, Scd1 expression and triglyceride fatty acid desaturation and increased tumorigenicity by PPARγ1. In contrast, PPARγ2 expression significantly increased basal cell differentiation, Scd1 expression and AR expression and responsiveness. Finally, in confirmation of in vitro data, a PPARγ agonist versus high-fat diet (HFD) regimen in vivo confirmed that PPARγ agonization increased prostatic differentiation markers, whereas HFD downregulated PPARγ-regulated genes and decreased prostate differentiation. These data provide a rationale for pursuing a fundamental metabolic understanding of changes to glucose and fatty acid metabolism in benign and malignant prostatic diseases associated with systemic metabolic stress.

Forkhead, a new cross regulator of metabolism and innate immunity downstream of TOR in Drosophila.

Science.gov (United States)

Varma, Disha; Bülow, Margret H; Pesch, Yanina-Yasmin; Loch, Gerrit; Hoch, Michael

2014-10-01

Antimicrobial peptides (AMPs) are conserved cationic peptides which act both as defense molecules of the host immune system and as regulators of the commensal microbiome. Expression of AMPs is induced in response to infection by the Toll and Imd pathway. Under non-infected conditions, the transcription factor dFOXO directly regulates a set of AMP expression at low levels when nutrients are limited. Here we have analyzed whether target of rapamycin (TOR), another major regulator of growth and metabolism, also modulates AMP responses in Drosophila. We found that downregulation of TOR by feeding the drug rapamycin or by overexpressing the negative TOR regulators TSC1/TSC2, resulted in a specific induction of the AMPs Diptericin (Dpt) and Metchnikowin (Mtk). In contrast, overexpression of Rheb, which positively regulates TOR led to a repression of the two AMPs. Genetic and pharmacological experiments indicate that Dpt and Mtk activation is controlled by the transcription factor Forkhead (FKH), the founding member of the FoxO family. Shuttling of FKH from the cytoplasm to the nucleus is induced in the fat body and in the posterior midgut in response to TOR downregulation. The FKH-dependent induction of Dpt and Mtk can be triggered in dFOXO null mutants and in immune-compromised Toll and IMD pathway mutants indicating that FKH acts in parallel to these regulators. Together, we have discovered that FKH is the second conserved member of the FoxO family cross-regulating metabolism and innate immunity. dFOXO and FKH, which are activated upon downregulation of insulin or TOR activities, respectively, act in parallel to induce different sets of AMPs, thereby modulating the immune status of metabolic tissues such as the fat body or the gut in response to the oscillating energy status of the organism. Copyright © 2014 Elsevier Ltd. All rights reserved.

Voluntary exercise prevents colonic inflammation in high-fat diet-induced obese mice by up-regulating PPAR-γ activity

International Nuclear Information System (INIS)

Liu, Wei-Xin; Wang, Ting; Zhou, Feng; Wang, Ying; Xing, Jun-Wei; Zhang, Shen; Gu, Shou-Zhi; Sang, Li-Xuan; Dai, Cong; Wang, Hai-Lan

2015-01-01

Obesity is associated with increased colonic inflammation, which elevates the risk of colon cancer. Although exercise exerts anti-inflammatory actions in multiple chronic diseases associated with inflammation, it is unknown whether this strategy prevents colonic inflammation in obesity. We hypothesized that voluntary exercise would suppress colonic inflammation in high-fat diet (HFD)-induced obesity by modulation of peroxisome proliferator-activated receptor (PPAR)-γ. Male C57Bl/6J mice fed either a control diet (6.5% fat, CON) or a high-fat diet (24% fat, HFD) were divided into sedentary, voluntary exercise or voluntary exercise with PPAR-γ antagonist GW9662 (10 mg/kg/day). All interventions took place for 12 weeks. Compared with CON-sedentary group, HFD-sedentary mice gained significantly more body weight and exhibited metabolic disorders. Molecular studies revealed that HFD-sedentary mice had increased expression of inflammatory mediators and activation of nuclear factor (NF)-κB in the colons, which were associated with decreased expression and activity of PPAR-γ. Voluntary exercise markedly attenuated body weight gain, improved metabolic disorders, and normalized the expression of inflammatory mediators and activation of NF-κB in the colons in HFD-mice while having no effects in CON-animals. Moreover, voluntary exercise significantly increased expression and activity of PPAR-γ in the colons in both HFD- and CON-animals. However, all of these beneficial effects induced by voluntary exercise were abolished by GW9662, which inhibited expression and activity of PPAR-γ. The results suggest that decreased PPAR-γ activity in the colon of HFD-induced obesity may facilitate the inflammatory response and colon carcinogenesis. Voluntary exercise prevents colonic inflammation in HFD-induced obesity by up-regulating PPAR-γ activity. - Highlights: • Obesity down-regulates PPAR-γ in the colon. • Down-regulated colonic PPAR-γ may facilitate inflammatory

Voluntary exercise prevents colonic inflammation in high-fat diet-induced obese mice by up-regulating PPAR-γ activity

Energy Technology Data Exchange (ETDEWEB)

Liu, Wei-Xin, E-mail: weixinliu@yahoo.com [Department of Gastroenterology, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Wang, Ting; Zhou, Feng; Wang, Ying; Xing, Jun-Wei; Zhang, Shen [Department of Gastroenterology, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Gu, Shou-Zhi [Department of Anatomy, Seirei Christopher College, Hamamatsu 433-8558 (Japan); Sang, Li-Xuan [Department of Cadre Ward II, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Dai, Cong [Department of Gastroenterology, First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning (China); Wang, Hai-Lan [Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou 510300, Guangdong (China)

2015-04-10

Obesity is associated with increased colonic inflammation, which elevates the risk of colon cancer. Although exercise exerts anti-inflammatory actions in multiple chronic diseases associated with inflammation, it is unknown whether this strategy prevents colonic inflammation in obesity. We hypothesized that voluntary exercise would suppress colonic inflammation in high-fat diet (HFD)-induced obesity by modulation of peroxisome proliferator-activated receptor (PPAR)-γ. Male C57Bl/6J mice fed either a control diet (6.5% fat, CON) or a high-fat diet (24% fat, HFD) were divided into sedentary, voluntary exercise or voluntary exercise with PPAR-γ antagonist GW9662 (10 mg/kg/day). All interventions took place for 12 weeks. Compared with CON-sedentary group, HFD-sedentary mice gained significantly more body weight and exhibited metabolic disorders. Molecular studies revealed that HFD-sedentary mice had increased expression of inflammatory mediators and activation of nuclear factor (NF)-κB in the colons, which were associated with decreased expression and activity of PPAR-γ. Voluntary exercise markedly attenuated body weight gain, improved metabolic disorders, and normalized the expression of inflammatory mediators and activation of NF-κB in the colons in HFD-mice while having no effects in CON-animals. Moreover, voluntary exercise significantly increased expression and activity of PPAR-γ in the colons in both HFD- and CON-animals. However, all of these beneficial effects induced by voluntary exercise were abolished by GW9662, which inhibited expression and activity of PPAR-γ. The results suggest that decreased PPAR-γ activity in the colon of HFD-induced obesity may facilitate the inflammatory response and colon carcinogenesis. Voluntary exercise prevents colonic inflammation in HFD-induced obesity by up-regulating PPAR-γ activity. - Highlights: • Obesity down-regulates PPAR-γ in the colon. • Down-regulated colonic PPAR-γ may facilitate inflammatory

Fat and carbohydrate metabolism during exercise in late-onset Pompe disease

DEFF Research Database (Denmark)

Preisler, Nicolai; Laforet, Pascal; Madsen, Karen Lindhardt

2012-01-01

forearm exercise testing, and peak work capacity was determined. Fat and carbohydrate metabolism during cycle exercise was examined with a combination of indirect calorimetry and stable isotope methodology. Finally, the effects of an IV glucose infusion on heart rate, ratings of perceived exertion...... examined the metabolic response to exercise in patients with late-onset Pompe disease, in order to determine if a defect in energy metabolism may play a role in the pathogenesis of Pompe disease. We studied six adult patients with Pompe disease and 10 healthy subjects. The participants underwent ischemic......, and work capacity during exercise were determined. We found that peak oxidative capacity was reduced in the patients to 17.6 vs. 38.8 ml kg(-1) min(-1) in healthy subjects (p = 0.002). There were no differences in the rate of appearance and rate of oxidation of palmitate, or total fat and carbohydrate...

Obestatin as a regulator of adipocyte metabolism and adipogenesis

Science.gov (United States)

Gurriarán-Rodríguez, Uxía; Al-Massadi, Omar; Roca-Rivada, Arturo; Crujeiras, Ana Belén; Gallego, Rosalía; Pardo, Maria; Seoane, Luisa Maria; Pazos, Yolanda; Casanueva, Felipe F; Camiña, Jesús P

2011-01-01

Abstract The role of obestatin, a 23-amino-acid peptide encoded by the ghrelin gene, on the control of the metabolism of pre-adipocyte and adipocytes as well as on adipogenesis was determined. For in vitro assays, pre-adipocyte and adipocyte 3T3-L1 cells were used to assess the obestatin effect on cell metabolism and adipogenesis based on the regulation of the key enzymatic nodes, Akt and AMPK and their downstream targets. For in vivo assays, white adipose tissue (WAT) was obtained from male rats under continuous subcutaneous infusion of obestatin. Obestatin activated Akt and its downstream targets, GSK3α/β, mTOR and S6K1, in 3T3-L1 adipocyte cells. Simultaneously, obestatin inactivated AMPK in this cell model. In keeping with this, ACC phosphorylation was also decreased. This fact was confirmed in vivo in white adipose tissue (omental, subcutaneous and gonadal) obtained from male rats under continuous sc infusion of obestatin (24 and 72 hrs). The relevance of obestatin as regulator of adipocyte metabolism was supported by AS160 phosphorylation, GLUT4 translocation and augment of glucose uptake in 3T3-L1 adipocyte cells. In contrast, obestatin failed to modify translocation of fatty acid transporters, FATP1, FATP4 and FAT/CD36, to plasma membrane. Obestatin treatment in combination with IBMX and DEX showed to regulate the expression of C/EBPα, C/EBPβ, C/EBPδ and PPARγ promoting adipogenesis. Remarkable, preproghrelin expression, and thus obestatin expression, increased during adipogenesis being sustained throughout terminal differentiation. Neutralization of endogenous obestatin secreted by 3T3-L1 cells by anti-obestatin antibody decreased adipocyte differentiation. Furthermore, knockdown experiments by preproghrelin siRNA supported that obestatin contributes to adipogenesis. In summary, obestatin promotes adipogenesis in an autocrine/paracrine manner, being a regulator of adipocyte metabolism. These data point to a putative role in the pathogenesis of

Skeletal muscle interleukin-6 regulates metabolic factors in iWAT during HFD and exercise training

DEFF Research Database (Denmark)

Knudsen, Jakob Grunnet; Bertholdt, Lærke; Joensen, Ella

2015-01-01

in combination with exercise training (HFD ExTr) for 16 weeks. RESULTS: Total fat mass increased (P mass than HFD Floxed mice. Accordingly, iWAT glucose transporter 4 (GLUT4) protein content, 5'AMP......OBJECTIVE: To investigate the role of skeletal muscle (SkM) interleukin (IL)-6 in the regulation of adipose tissue metabolism. METHODS: Muscle-specific IL-6 knockout (IL-6 MKO) and IL-6(loxP/loxP) (Floxed) mice were subjected to standard rodent diet (Chow), high-fat diet (HFD), or HFD.......05) in HFD IL-6 MKO than HFD Floxed mice, and pyruvate dehydrogenase E1α (PDH-E1α) protein content was higher (P mass through regulation of glucose uptake capacity as well as lipogenic...

Fatty acids from diet and microbiota regulate energy metabolism [version 1; referees: 2 approved

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Joe Alcock

2015-09-01

Full Text Available A high-fat diet and elevated levels of free fatty acids are known risk factors for metabolic syndrome, insulin resistance, and visceral obesity. Although these disease associations are well established, it is unclear how different dietary fats change the risk of insulin resistance and metabolic syndrome. Here, we review emerging evidence that insulin resistance and fat storage are linked to changes in the gut microbiota. The gut microbiota and intestinal barrier function, in turn, are highly influenced by the composition of fat in the diet. We review findings that certain fats (for example, long-chain saturated fatty acids are associated with dysbiosis, impairment of intestinal barrier function, and metabolic endotoxemia. In contrast, other fatty acids, including short-chain and certain unsaturated fatty acids, protect against dysbiosis and impairment of barrier function caused by other dietary fats. These fats may promote insulin sensitivity by inhibiting metabolic endotoxemia and dysbiosis-driven inflammation. During dysbiosis, the modulation of metabolism by diet and microbiota may represent an adaptive process that compensates for the increased fuel demands of an activated immune system.

ER-tethered Transcription Factor CREBH Regulates Hepatic Lipogenesis, Fatty Acid Oxidation, and Lipolysis upon Metabolic Stress

OpenAIRE

Zhang, Chunbin; Wang, Guohui; Zheng, Ze; Maddipati, Krishna Rao; Zhang, Xuebao; Dyson, Gregory; Williams, Paul; Duncan, Stephen A.; Kaufman, Randal J.; Zhang, Kezhong

2012-01-01

CREBH is a liver-specific transcription factor that is localized in the endoplasmic reticulum (ER) membrane. Our previous work demonstrated that CREBH is activated by ER stress or inflammatory stimuli to induce an acute-phase hepatic inflammation. Here we demonstrate that CREBH is a key metabolic regulator of hepatic lipogenesis, fatty acid (FA) oxidation, and lipolysis under metabolic stress. Saturated FA, insulin signals, or an atherogenic high-fat diet can induce CREBH activation in the li...

Do obese but metabolically normal women differ in intra-abdominal fat and physical activity levels from those with the expected metabolic abnormalities? A cross-sectional study

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Walker Mark

2010-11-01

Full Text Available Abstract Background Obesity remains a major public health problem, associated with a cluster of metabolic abnormalities. However, individuals exist who are very obese but have normal metabolic parameters. The aim of this study was to determine to what extent differences in metabolic health in very obese women are explained by differences in body fat distribution, insulin resistance and level of physical activity. Methods This was a cross-sectional pilot study of 39 obese women (age: 28-64 yrs, BMI: 31-67 kg/m2 recruited from community settings. Women were defined as 'metabolically normal' on the basis of blood glucose, lipids and blood pressure. Magnetic Resonance Imaging was used to determine body fat distribution. Detailed lifestyle and metabolic profiles of participants were obtained. Results Women with a healthy metabolic profile had lower intra-abdominal fat volume (geometric mean 4.78 l [95% CIs 3.99-5.73] vs 6.96 l [5.82-8.32] and less insulin resistance (HOMA 3.41 [2.62-4.44] vs 6.67 [5.02-8.86] than those with an abnormality. The groups did not differ in abdominal subcutaneous fat volume (19.6 l [16.9-22.7] vs 20.6 [17.6-23.9]. A higher proportion of those with a healthy compared to a less healthy metabolic profile met current physical activity guidelines (70% [95% CIs 55.8-84.2] vs 25% [11.6-38.4]. Intra-abdominal fat, insulin resistance and physical activity make independent contributions to metabolic status in very obese women, but explain only around a third of the variance. Conclusion A sub-group of women exists who are metabolically normal despite being very obese. Differences in fat distribution, insulin resistance, and physical activity level are associated with metabolic differences in these women, but account only partially for these differences. Future work should focus on strategies to identify those obese individuals most at risk of the negative metabolic consequences of obesity and on identifying other factors that

Ellagic acid attenuates high-carbohydrate, high-fat diet-induced metabolic syndrome in rats.

Science.gov (United States)

Panchal, Sunil K; Ward, Leigh; Brown, Lindsay

2013-03-01

Fruits and nuts may prevent or reverse common human health conditions such as obesity, diabetes and hypertension; together, these conditions are referred to as metabolic syndrome, an increasing problem. This study has investigated the responses to ellagic acid, present in many fruits and nuts, in a diet-induced rat model of metabolic syndrome. Eight- to nine-week-old male Wistar rats were divided into four groups for 16-week feeding with cornstarch diet (C), cornstarch diet supplemented with ellagic acid (CE), high-carbohydrate, high-fat diet (H) and high-carbohydrate, high-fat diet supplemented with ellagic acid (HE). CE and HE rats were given 0.8 g/kg ellagic acid in food from week 8 to 16 only. At the end of 16 weeks, cardiovascular, hepatic and metabolic parameters along with protein levels of Nrf2, NF-κB and CPT1 in the heart and the liver were characterised. High-carbohydrate, high-fat diet-fed rats developed cardiovascular remodelling, impaired ventricular function, impaired glucose tolerance, non-alcoholic fatty liver disease with increased protein levels of NF-κB and decreased protein levels of Nrf2 and CPT1 in the heart and the liver. Ellagic acid attenuated these diet-induced symptoms of metabolic syndrome with normalisation of protein levels of Nrf2, NF-κB and CPT1. Ellagic acid derived from nuts and fruits such as raspberries and pomegranates may provide a useful dietary supplement to decrease the characteristic changes in metabolism and in cardiac and hepatic structure and function induced by a high-carbohydrate, high-fat diet by suppressing oxidative stress and inflammation.

Elucidation of molecular mechanisms of physiological variations between bovine subcutaneous and visceral fat depots under different nutritional regimes.

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Josue Moura Romao

Full Text Available Adipose tissue plays a critical role in energy homeostasis and metabolism. There is sparse understanding of the molecular regulation at the protein level of bovine adipose tissues, especially within different fat depots under different nutritional regimes. The objective of this study was to analyze the differences in protein expression between bovine subcutaneous and visceral fat depots in steers fed different diets and to identify the potential regulatory molecular mechanisms of protein expression. Subcutaneous and visceral fat tissues were collected from 16 British-continental steers (15.5 month old fed a high-fat diet (7.1% fat, n=8 or a control diet (2.7% fat, n=8. Protein expression was profiled using label free quantification LC-MS/MS and expression of selected transcripts was evaluated using qRT-PCR. A total of 682 proteins were characterized and quantified with fat depot having more impact on protein expression, altering the level of 51.0% of the detected proteins, whereas diet affected only 5.3%. Functional analysis revealed that energy production and lipid metabolism were among the main functions associated with differentially expressed proteins between fat depots, with visceral fat being more metabolically active than subcutaneous fat as proteins associated with lipid and energy metabolism were upregulated. The expression of several proteins was significantly correlated to subcutaneous fat thickness and adipocyte size, indicating their potential as adiposity markers. A poor correlation (r=0.245 was observed between mRNA and protein levels for 9 genes, indicating that many proteins may be subjected to post-transcriptional regulation. A total of 8 miRNAs were predicted to regulate more than 20% of lipid metabolism proteins differentially expressed between fat depots, suggesting that miRNAs play a role in adipose tissue regulation. Our results show that proteomic changes support the distinct metabolic and physiological characteristics

Metabolic syndrome in Japanese diagnosed with visceral fat measurement by computed tomography

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Miyawaki, Takashi; Aono, Hideshi; Saito, Nobuo; Hirata, Masakazu; Nakao, Kazuwa; Moriyama, Kenji; Sasaki, Yutaka

2005-01-01

The metabolic syndrome represents an aggregation of cardiovascular risk factors including obesity, raised blood pressure, impaired glucose tolerance, and dyslipidemia that are associated with increased incidence of arteriosclerosis. Evidence accumulated indicates that the visceral fat accumulation is essential in the development of the syndrome. To investigate the prevalence of the metabolic syndrome in Japan, we analyzed cross-sectional data from 3574 middle aged Japanese (2947 men and 627 women, aged 40-59 years) in a large company, whose visceral fat accumulation was assessed by computed tomography. We employed receiver operation characteristic analysis to identify the optimal visceral fat area (VFA) value that has the sensitivity and the specificity to predict the presence of at least two components of the syndrome in an individual. The sensitivities and the specificities for men were 0.67 and 0.60 at VFA of 100 cm 2 , and for women, 0.73 and 0.70 at VFA of 65 cm 2 , respectively. Waist circumferences that corresponded to the VFA cutoff were 86.0 cm for men, and 77.0 cm for women. Using 100 cm 2 in men and 65 cm 2 in women as the criteria of visceral adiposity, the prevalence of the metabolic syndrome was 25.5% in men and 11.0% in women. Although obesity is less prevalent than in western countries, the metabolic syndrome is substantially widespread in Japan. (author)

Dietary fat influences the expression of contractile and metabolic genes in rat skeletal muscle.

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Wataru Mizunoya

Full Text Available Dietary fat plays a major role in obesity, lipid metabolism, and cardiovascular diseases. To determine whether the intake of different types of dietary fats affect the muscle fiber types that govern the metabolic and contractile properties of the skeletal muscle, we fed male Wistar rats with a 15% fat diet derived from different fat sources. Diets composed of soybean oil (n-6 polyunsaturated fatty acids (PUFA-rich, fish oil (n-3 PUFA-rich, or lard (low in PUFAs were administered to the rats for 4 weeks. Myosin heavy chain (MyHC isoforms were used as biomarkers to delineate the skeletal muscle fiber types. Compared with soybean oil intake, fish oil intake showed significantly lower levels of the fast-type MyHC2B and higher levels of the intermediate-type MyHC2X composition in the extensor digitorum longus (EDL muscle, which is a fast-type dominant muscle. Concomitantly, MyHC2X mRNA levels in fish oil-fed rats were significantly higher than those observed in the soybean oil-fed rats. The MyHC isoform composition in the lard-fed rats was an intermediate between that of the fish oil and soybean oil-fed rats. Mitochondrial uncoupling protein 3, pyruvate dehydrogenase kinase 4, and porin mRNA showed significantly upregulated levels in the EDL of fish oil-fed rats compared to those observed in soybean oil-fed and lard-fed rats, implying an activation of oxidative metabolism. In contrast, no changes in the composition of MyHC isoforms was observed in the soleus muscle, which is a slow-type dominant muscle. Fatty acid composition in the serum and the muscle was significantly influenced by the type of dietary fat consumed. In conclusion, dietary fat affects the expression of genes related to the contractile and metabolic properties in the fast-type dominant skeletal muscle, where the activation of oxidative metabolism is more pronounced after fish oil intake than that after soybean oil intake.

Regulation of lipid deposition in farm animals: Parallels between agriculture and human physiology.

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Bergen, Werner G; Brandebourg, Terry D

2016-06-01

For many years, clinically oriented scientists and animal scientists have focused on lipid metabolism and fat deposition in various fat depots. While dealing with a common biology across species, the goals of biomedical and food animals lipid metabolism research differ in emphasis. In humans, mechanisms and regulation of fat synthesis, accumulation of fat in regional fat depots, lipid metabolism and dysmetabolism in adipose, liver and cardiac tissues have been investigated. Further, energy balance and weight control have also been extensively explored in humans. Finally, obesity and associated maladies including high cholesterol and atherosclerosis, cardiovascular disease, insulin resistance, hypertension, metabolic syndrome and health outcomes have been widely studied. In food animals, the emphasis has been on regulation of fatty acid synthesis and lipid deposition in fat depots and deposition of intramuscular fat. For humans, understanding the regulation of energy balance and body weight and of prevention or treatment of obesity and associated maladies have been important clinical outcomes. In production of food animals lowering fat content in muscle foods while enhancing intramuscular fat (marbling) have been major targets. In this review, we summarize how our laboratories have addressed the goal of providing lean but yet tasty and juicy muscle food products to consumers. In addition, we here describe efforts in the development of a new porcine model to study regulation of fat metabolism and obesity. Commonalities and differences in regulation of lipid metabolism between humans, rodents and food animals are emphasized throughout this review. © 2016 by the Society for Experimental Biology and Medicine.

Chitin Oligosaccharide Modulates Gut Microbiota and Attenuates High-Fat-Diet-Induced Metabolic Syndrome in Mice

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Junping Zheng

2018-02-01

Full Text Available Gut microbiota has been proved to be an indispensable link between nutrient excess and metabolic syndrome, and chitin oligosaccharide (NACOS has displayed therapeutic effects on multiple diseases such as cancer and gastritis. In this study, we aim to confirm whether NACOS can ameliorate high-fat diet (HFD-induced metabolic syndrome by rebuilding the structure of the gut microbiota community. Male C57BL/6J mice fed with HFD were treated with NACOS (1 mg/mL in drinking water for five months. The results indicate that NACOS improved glucose metabolic disorder in HFD-fed mice and suppressed mRNA expression of the protein regulators related to lipogenesis, gluconeogenesis, adipocyte differentiation, and inflammation in adipose tissues. Additionally, NACOS inhibited the destruction of the gut barrier in HFD-treated mice. Furthermore, 16S ribosome RNA sequencing of fecal samples demonstrates that NACOS promoted the growth of beneficial intestinal bacteria remarkably and decreased the abundance of inflammogenic taxa. In summary, NACOS partly rebuilt the microbial community and improved the metabolic syndrome of HFD-fed mice. These data confirm the preventive effects of NACOS on nutrient excess-related metabolic diseases.

Gold-quercetin nanoparticles prevent metabolic endotoxemia-induced kidney injury by regulating TLR4/NF-κB signaling and Nrf2 pathway in high fat diet fed mice.

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Xu, Min-Xuan; Wang, Ming; Yang, Wei-Wei

2017-01-01

High-fat diet-induced metabolic syndrome followed by chronic kidney disease caused by intestinal endotoxemia have received extensive attention. Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) and oxidative stress-related Nrf2/Keap1 were regarded as the key target points involved in metabolic inflammation and kidney injury. However, the molecular mechanism of interaction between TLR4/NF-κB and Nrf2 activation in high-fat diet-induced renal injury is not absolutely understood. Quercetin, a natural product, has been reported to possess antitumor and anti-inflammatory effects. In this regard, this study attempted to prepare poly(d,l-lactide- co -glycolide)-loaded gold nanoparticles precipitated with quercetin (GQ) to investigate the anti-inflammatory and anti-oxidative stress effects in high-fat diet-induced kidney failure. For this study, C57BL/6 mice fed fat-rich fodder were used as the metabolic syndrome model to evaluate the protective effects of GQ on kidney injury and to determine whether TLR4/NF-κB and Nrf2 pathways were associated with the process. Moreover, histological examinations, enzyme-linked immunosorbent assay, Western blot, and basic blood tests and systemic inflammation-related indicators were used to investigate the inhibitory effects of GQ and underlying molecular mechanism by which it may reduce renal injury. Of note, podocyte injury was found to participate in endotoxin-stimulated inflammatory response. TLR4/NF-κB and Nrf2 pathways were upregulated with high-fat diet intake in mice, resulting in reduction of superoxide dismutase activity and increase in superoxide radical, H 2 O 2 , malondialdehyde, XO, XDH, and XO/XDH ratio. In addition, upregulation of TLR4/NF-κB and oxidative stress by endotoxin were observed in vitro, which were suppressed by GQ administration, ultimately alleviating podocyte injury. These findings indicated that GQ could restore the metabolic disorders caused by high-fat diet, which suppresses insulin

Body weight regulation and obesity: dietary strategies to improve the metabolic profile.

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Munsters, M J M; Saris, W H M

2014-01-01

This review discusses dietary strategies that may improve the metabolic profile and body weight regulation in obesity. Recent evidence demonstrated that long-term health effects seem to be more beneficial for low-glycemic index (GI) diets compared to high-protein diets. Still, these results need to be confirmed by other prospective cohort studies and long-term clinical trials, and the discrepancy between these study designs needs to be explored in more detail. Furthermore, the current literature is mixed with regard to the efficacy of increased meal frequency (or snacking) regimens in causing metabolic alterations, particularly in relation to body weight control. In conclusion, a growing body of evidence suggests that dietary strategies with the aim to reduce postprandial insulin response and increase fat oxidation, and that tend to restore metabolic flexibility, have a place in the prevention and treatment of obesity and associated metabolic disorders.

ACE Reduces Metabolic Abnormalities in a High-Fat Diet Mouse Model

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Seong-Jong Lee

2015-01-01

Full Text Available The medicinal plants Artemisia iwayomogi (A. iwayomogi and Curcuma longa (C. longa radix have been used to treat metabolic abnormalities in traditional Korean medicine and traditional Chinese medicine (TKM and TCM. In this study we evaluated the effect of the water extract of a mixture of A. iwayomogi and C. longa (ACE on high-fat diet-induced metabolic syndrome in a mouse model. Four groups of C57BL/6N male mice (except for the naive group were fed a high-fat diet freely for 10 weeks. Among these, three groups (except the control group were administered a high-fat diet supplemented with ACE (100 or 200 mg/kg or curcumin (50 mg/kg. Body weight, accumulation of adipose tissues in abdomen and size of adipocytes, serum lipid profiles, hepatic steatosis, and oxidative stress markers were analyzed. ACE significantly reduced the body and peritoneal adipose tissue weights, serum lipid profiles (total cholesterol and triglycerides, glucose levels, hepatic lipid accumulation, and oxidative stress markers. ACE normalized lipid synthesis-associated gene expressions (peroxisome proliferator-activated receptor gamma, PPARγ; fatty acid synthase, FAS; sterol regulatory element-binding transcription factor-1c, SREBP-1c; and peroxisome proliferator-activated receptor alpha, PPARα. The results from this study suggest that ACE has the pharmaceutical potential reducing the metabolic abnormalities in an animal model.

The concept of metabolic syndrome: contribution of visceral fat accumulation and its molecular mechanism.

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Matsuzawa, Yuji; Funahashi, Tohru; Nakamura, Tadashi

2011-01-01

Although abdominal obesity or visceral obesity is considered to be one of the components of metabolic syndrome and to have an important role in a cluster of cardiovascular risks, there is no consensus about the definition and diagnostic criteria for this syndrome, probably because there is considerable disagreement about the location and definition of abdominal obesity or visceral obesity.In this review article, the important role of visceral fat accumulation in the development of a variety of lifestyle-related diseases is shown, including cardiovascular disease based on our clinical studies using CT scans, and the mechanism of these disorders is discussed, focusing on adipocytokines, especially adiponectin.The importance of diagnosing metabolic syndrome, in which visceral fat accumulation plays an essential role in the development of multiple risk factors, should be emphasized because lifestyle modification for the reduction of visceral fat may be very effective for the reduction of risks of this type, namely metabolic syndrome in the narrow sense.

Seaweed supplements normalise metabolic, cardiovascular and liver responses in high-carbohydrate, high-fat fed rats.

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Kumar, Senthil Arun; Magnusson, Marie; Ward, Leigh C; Paul, Nicholas A; Brown, Lindsay

2015-02-02

Increased seaweed consumption may be linked to the lower incidence of metabolic syndrome in eastern Asia. This study investigated the responses to two tropical green seaweeds, Ulva ohnoi (UO) and Derbesia tenuissima (DT), in a rat model of human metabolic syndrome. Male Wistar rats (330-340 g) were fed either a corn starch-rich diet or a high-carbohydrate, high-fat diet with 25% fructose in drinking water, for 16 weeks. High-carbohydrate, high-fat diet-fed rats showed the signs of metabolic syndrome leading to abdominal obesity, cardiovascular remodelling and non-alcoholic fatty liver disease. Food was supplemented with 5% dried UO or DT for the final 8 weeks only. UO lowered total final body fat mass by 24%, systolic blood pressure by 29 mmHg, and improved glucose utilisation and insulin sensitivity. In contrast, DT did not change total body fat mass but decreased plasma triglycerides by 38% and total cholesterol by 17%. UO contained 18.1% soluble fibre as part of 40.9% total fibre, and increased magnesium, while DT contained 23.4% total fibre, essentially as insoluble fibre. UO was more effective in reducing metabolic syndrome than DT, possibly due to the increased intake of soluble fibre and magnesium.

Seaweed Supplements Normalise Metabolic, Cardiovascular and Liver Responses in High-Carbohydrate, High-Fat Fed Rats

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Senthil Arun Kumar

2015-02-01

Full Text Available Increased seaweed consumption may be linked to the lower incidence of metabolic syndrome in eastern Asia. This study investigated the responses to two tropical green seaweeds, Ulva ohnoi (UO and Derbesia tenuissima (DT, in a rat model of human metabolic syndrome. Male Wistar rats (330–340 g were fed either a corn starch-rich diet or a high-carbohydrate, high-fat diet with 25% fructose in drinking water, for 16 weeks. High-carbohydrate, high-fat diet-fed rats showed the signs of metabolic syndrome leading to abdominal obesity, cardiovascular remodelling and non-alcoholic fatty liver disease. Food was supplemented with 5% dried UO or DT for the final 8 weeks only. UO lowered total final body fat mass by 24%, systolic blood pressure by 29 mmHg, and improved glucose utilisation and insulin sensitivity. In contrast, DT did not change total body fat mass but decreased plasma triglycerides by 38% and total cholesterol by 17%. UO contained 18.1% soluble fibre as part of 40.9% total fibre, and increased magnesium, while DT contained 23.4% total fibre, essentially as insoluble fibre. UO was more effective in reducing metabolic syndrome than DT, possibly due to the increased intake of soluble fibre and magnesium.

Seaweed Supplements Normalise Metabolic, Cardiovascular and Liver Responses in High-Carbohydrate, High-Fat Fed Rats

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Kumar, Senthil Arun; Magnusson, Marie; Ward, Leigh C.; Paul, Nicholas A.; Brown, Lindsay

2015-01-01

Increased seaweed consumption may be linked to the lower incidence of metabolic syndrome in eastern Asia. This study investigated the responses to two tropical green seaweeds, Ulva ohnoi (UO) and Derbesia tenuissima (DT), in a rat model of human metabolic syndrome. Male Wistar rats (330–340 g) were fed either a corn starch-rich diet or a high-carbohydrate, high-fat diet with 25% fructose in drinking water, for 16 weeks. High-carbohydrate, high-fat diet-fed rats showed the signs of metabolic syndrome leading to abdominal obesity, cardiovascular remodelling and non-alcoholic fatty liver disease. Food was supplemented with 5% dried UO or DT for the final 8 weeks only. UO lowered total final body fat mass by 24%, systolic blood pressure by 29 mmHg, and improved glucose utilisation and insulin sensitivity. In contrast, DT did not change total body fat mass but decreased plasma triglycerides by 38% and total cholesterol by 17%. UO contained 18.1% soluble fibre as part of 40.9% total fibre, and increased magnesium, while DT contained 23.4% total fibre, essentially as insoluble fibre. UO was more effective in reducing metabolic syndrome than DT, possibly due to the increased intake of soluble fibre and magnesium. PMID:25648511

Mice lacking natural killer T cells are more susceptible to metabolic alterations following high fat diet feeding.

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Brittany V Martin-Murphy

Full Text Available Current estimates suggest that over one-third of the adult population has metabolic syndrome and three-fourths of the obese population has non-alcoholic fatty liver disease (NAFLD. Inflammation in metabolic tissues has emerged as a universal feature of obesity and its co-morbidities, including NAFLD. Natural Killer T (NKT cells are a subset of innate immune cells that abundantly reside within the liver and are readily activated by lipid antigens. There is general consensus that NKT cells are pivotal regulators of inflammation; however, disagreement exists as to whether NKT cells exert pathogenic or suppressive functions in obesity. Here we demonstrate that CD1d(-/- mice, which lack NKT cells, were more susceptible to weight gain and fatty liver following high fat diet (HFD feeding. Compared with their WT counterparts, CD1d(-/- mice displayed increased adiposity and greater induction of inflammatory genes in the liver suggestive of the precursors of NAFLD. Calorimetry studies revealed a significant increase in food intake and trends toward decreased metabolic rate and activity in CD1d(-/- mice compared with WT mice. Based on these findings, our results suggest that NKT cells play a regulatory role that helps to prevent diet-induced obesity and metabolic dysfunction and may play an important role in mechanisms governing cross-talk between metabolism and the immune system to regulate energy balance and liver health.

Metabolic syndrome in Japanese diagnosed with visceral fat measurement by computed tomography

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Miyawaki, Takashi; Aono, Hideshi; Saito, Nobuo [NTT West Kyoto Hospital, Health Administration Center, Kyoto, Kyoto (Japan); Hirata, Masakazu; Nakao, Kazuwa [Kyoto Univ., Graduate School of Medicine, Kyoto, Kyoto (Japan); Moriyama, Kenji; Sasaki, Yutaka [NTT West Corp., Kansai Health Administration Center, Kyoto, Kyoto (Japan)

2005-09-15

The metabolic syndrome represents an aggregation of cardiovascular risk factors including obesity, raised blood pressure, impaired glucose tolerance, and dyslipidemia that are associated with increased incidence of arteriosclerosis. Evidence accumulated indicates that the visceral fat accumulation is essential in the development of the syndrome. To investigate the prevalence of the metabolic syndrome in Japan, we analyzed cross-sectional data from 3574 middle aged Japanese (2947 men and 627 women, aged 40-59 years) in a large company, whose visceral fat accumulation was assessed by computed tomography. We employed receiver operation characteristic analysis to identify the optimal visceral fat area (VFA) value that has the sensitivity and the specificity to predict the presence of at least two components of the syndrome in an individual. The sensitivities and the specificities for men were 0.67 and 0.60 at VFA of 100 cm{sup 2}, and for women, 0.73 and 0.70 at VFA of 65 cm{sup 2}, respectively. Waist circumferences that corresponded to the VFA cutoff were 86.0 cm for men, and 77.0 cm for women. Using 100 cm{sup 2} in men and 65 cm{sup 2} in women as the criteria of visceral adiposity, the prevalence of the metabolic syndrome was 25.5% in men and 11.0% in women. Although obesity is less prevalent than in western countries, the metabolic syndrome is substantially widespread in Japan. (author)

Diet-gene interactions between dietary fat intake and common polymorphisms in determining lipid metabolism

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Corella, D.

2009-07-01

Current dietary guidelines for fat intake have not taken into consideration the possible genetic differences underlying the individual variability in responsiveness to dietary components. Genetic variability has been identified in humans for all the known lipid metabolism-related genes resulting in a plethora of candidate genes and genetic variants to examine in diet-gene interaction studies focused on fat consumption. Some examples of fat-gene interaction are reviewed. These include: the interaction between total intake and the 14C/T in the hepatic lipase gene promoter in determining high-density lipoprotein cholesterol (HDL-C) metabolism; the interaction between polyunsaturated fatty acids (PUFA) and the 5G/A polymorphism in the APOA1 gene plasma HDL-C concentrations; the interaction between PUFA and the L162V polymorphism in the PPARA gene in determining triglycerides and APOC3 concentrations; and the interaction between PUFA intake and the -1131T>C in the APOA5 gene in determining triglyceride metabolism. Although hundreds of diet-gene interaction studies in lipid metabolism have been published, the level of evidence to make specific nutritional recommendations to the population is still low and more research in nutrigenetics has to be undertaken. (Author) 31 refs.

Distal, not proximal, colonic acetate infusions promote fat oxidation and improve metabolic markers in overweight/obese men

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van der Beek, Christina M; Canfora, Emanuel E; Lenaerts, Kaatje

2016-01-01

, circulating hormones or inflammatory markers. In conclusion distal colonic acetate infusions affected whole-body substrate metabolism, with a pronounced increase in fasting fat oxidation and plasma PYY. Modulating colonic acetate may be a nutritional target to treat or prevent metabolic disorders.......Gut microbial-derived short-chain fatty acids (SCFA) are believed to affect host metabolism and cardiometabolic risk factors. The present study aim was to investigate the effects of proximal and distal colonic infusions with the SCFA acetate on fat oxidation and other metabolic parameters in men...... in the colon for three consecutive test days, enabling colonic acetate (100 or 180 mmol/l) or placebo infusion during fasting conditions and after an oral glucose load (postprandial). Fat oxidation and energy expenditure were measured using an open-circuit ventilated hood system and blood samples were...

Evaluation of abdominal fat index by ultrasonography and its relationship with psoriasis and metabolic syndrome.

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Gönül, Müzeyyen; Tatar, İdil; Canpolat, Filiz; Işıl Kurmus, Gökçe; Ergin, Can; Hekimoğlu, Baki

2017-10-01

Accumulating evidence indicates that psoriasis is associated with obesity and metabolic syndrome. Psoriasis and obesity share similar inflammatory mediators, and obesity may potentiate some inflammatory cytokines seen in psoriasis. Body fat distribution, particularly visceral adipose tissue (VAT), is an important factor in metabolic syndrome and atherosclerotic diseases. An association has been demonstrated between psoriasis and abdominal VAT measured by computed tomography (CT). To measure abdominal VAT noninvasively by ultrasonography (USG) in patients with psoriasis and investigated its relation to psoriasis and metabolic syndrome. The study population consisted of 41 psoriasis patients and 41 control subjects matched for age, sex, and body mass index. The maximal preperitoneal fat thickness (Pmax) at the anterior surface of the liver and the minimal subcutaneous fat thickness (Smin) of the abdomen were measured by USG. The abdominal fat index (AFI = Pmax/Smin ratio) was calculated and the results were compared between groups. The rate of metabolic syndrome was significantly higher in psoriasis patients ( p = 0.0018). The mean AFI was similar in both groups. AFI was not associated with psoriasis in subjects with metabolic syndrome ( p = 0.495) or with Psoriasis Area and Severity Index ( r = 0.123, p = 0.443). This is the first study to evaluate abdominal VAT by USG. Computed tomography may be more reliable than USG, but its high cost and radiation exposure are major disadvantages. Further studies are required to determine the relationships between psoriasis and VAT.

Bile acids are important direct and indirect regulators of the secretion of appetite- and metabolism-regulating hormones from the gut and pancreas

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Kuhre, Rune Ehrenreich; Albrechtsen, Nicolai Jacob Wewer; Larsen, Olav

2018-01-01

OBJECTIVE: Bile acids (BAs) facilitate fat absorption and may play a role in glucose and metabolism regulation, stimulating the secretion of gut hormones. The relative importance and mechanisms involved in BA-stimulated secretion of appetite and metabolism regulating hormones from the gut...... and pancreas is not well described and was the purpose of this study. METHODS: The effects of bile acids on the secretion of gut and pancreatic hormones was studied in rats and compared to the most well described nutritional secretagogue: glucose. The molecular mechanisms that underlie the secretion...... was studied by isolated perfused rat and mouse small intestine and pancreas preparations and supported by immunohistochemistry, expression analysis, and pharmacological studies. RESULTS: Bile acids robustly stimulate secretion of not only the incretin hormones, glucose-dependent insulinotropic peptide (GIP...

Evaluation of Beneficial Metabolic Effects of Berries in High-Fat Fed C57BL/6J Mice

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Lovisa Heyman

2014-01-01

Full Text Available Objective. The aim of the study was to screen eight species of berries for their ability to prevent obesity and metabolic abnormalities associated with type 2 diabetes. Methods. C57BL/6J mice were assigned the following diets for 13 weeks: low-fat diet, high-fat diet or high-fat diet supplemented (20% with lingonberry, blackcurrant, bilberry, raspberry, açai, crowberry, prune or blackberry. Results. The groups receiving a high-fat diet supplemented with lingonberries, blackcurrants, raspberries or bilberries gained less weight and had lower fasting insulin levels than the control group receiving high-fat diet without berries. Lingonberries, and also blackcurrants and bilberries, significantly decreased body fat content, hepatic lipid accumulation, and plasma levels of the inflammatory marker PAI-1, as well as mediated positive effects on glucose homeostasis. The group receiving açai displayed increased weight gain and developed large, steatotic livers. Quercetin glycosides were detected in the lingonberry and the blackcurrant diets. Conclusion. Lingonberries were shown to fully or partially prevent the detrimental metabolic effects induced by high-fat diet. Blackcurrants and bilberries had similar properties, but to a lower degree. We propose that the beneficial metabolic effects of lingonberries could be useful in preventing obesity and related disorders.

Bioactive Lipids in Dairy Fat

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Hellgren, Lars; Nordby, Pernille

2017-01-01

Milk fat is the most important energy source for the newborn infant beside its important role as energy source, milk fat also contain a range of bioactive lipids, that potentially can modulate the immune response and metabolic regulation in the child. In this chapter we review the literature on b...... on bioactive dairy fatty acids: conjugated linoleic acid, branched chained and odd chained fatty acids, as well as bioactive complex lipids such as sphingomyelin and gangliosides....

Naringin ameliorates metabolic syndrome by activating AMP-activated protein kinase in mice fed a high-fat diet.

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Pu, Peng; Gao, Dong-Mei; Mohamed, Salim; Chen, Jing; Zhang, Jing; Zhou, Xiao-Ya; Zhou, Nai-Jing; Xie, Jing; Jiang, Hong

2012-02-01

Metabolic syndrome is a low-grade inflammatory state in which oxidative stress is involved. Naringin, isolated from the Citrussinensis, is a phenolic compound with anti-oxidative and anti-inflammatory activities. The aim of this study was to explore the effects of naringin on metabolic syndrome in mice. The animal models, induced by high-fat diet in C57BL/6 mice, developed obesity, dyslipidemia, fatty liver, liver dysfunction and insulin resistance. These changes were attenuated by naringin. Further investigations revealed that the inhibitory effect on inflammation and insulin resistance was mediated by blocking activation of the MAPKs pathways and by activating IRS1; the lipid-lowering effect was attributed to inhibiting the synthesis way and increasing fatty acid oxidation; the hypoglycemic effect was due to the regulation of PEPCK and G6pase. The anti-oxidative stress of naringin also participated in the improvement of insulin resistance and lipogenesis. All of these depended on the AMPK activation. To confirm the results of the animal experiment, we tested primary hepatocytes exposed to high glucose system. Naringin was protective by phosphorylating AMPKα and IRS1. Taken together, these results suggested that naringin protected mice exposed to a high-fat diet from metabolic syndrome through an AMPK-dependent mechanism involving multiple types of intracellular signaling and reduction of oxidative damage. Copyright © 2011 Elsevier Inc. All rights reserved.

FAT-FREE MASS, METABOLICALLY HEALTHY OBESITY, AND TYPE 2 DIABETES IN SEVERELY OBESE ASIAN ADULTS.

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Pramyothin, Pornpoj; Limpattanachart, Vichol; Dawilai, Suwitcha; Sarasak, Rungnapha; Sukaruttanawong, Chariya; Chaiyasoot, Kusuma; Keawtanom, Songsri; Yamwong, Preyanuj

2017-08-01

To determine whether fat free mass (FFM) is independently associated with the metabolically healthy obesity (MHO) phenotype, the metabolic syndrome (MS), and type 2 diabetes (T2D) in obese Asian adults. Obese patients (body mass index [BMI] ≥25 kg/m 2 ) seeking weight management at an academic medical center from 2007 to 2016 were included. FFM was measured by bioelectrical impedance. Of the 552 patients (67.0% female, median age 40.5 years, median BMI 38.3 kg/m 2 ), MHO was present in 19%, MS in 55.4%, and T2D in 32.6%. In multivariate models, higher fat-free mass index (FFMI) was independently associated with the metabolically abnormal obesity (MAO) phenotype, (odds ratio [OR] 1.22, 95% confidence interval [CI] 1.09-1.37), and increased risk of MS (OR 1.12, 95% CI 1.03-1.22) in women but not in men. Older age was independently associated with the MAO phenotype (OR 1.06, 95% CI 1.04-1.09 in women; OR 1.06, 95% CI 1.02-1.09 in men), MS (OR 1.05, 95% CI 1.03-1.06 in women; OR 1.05, 95% CI 1.02-1.07 in men), and T2D (OR 1.07, 95% CI 1.05-1.09 in women; OR 1.06, 95% CI 1.04-1.09 in men). Waist-hip ratio was independently associated with the MAO phenotype in men (OR 1.08, 95% CI 1.01-1.15), while waist circumference was associated with T2D in women (OR 1.03, 95% CI 1.01-1.05). Older age, central fat distribution, and-in contrast to previous findings-an increase in FFMI among women were independent predictors of adverse metabolic health in this cohort of middle-aged obese Asian adults. Further studies are required to elucidate underlying mechanisms and therapeutic implications of these findings. BIA = bioelectrical impedance analysis BMI = body mass index CI = confidence interval DXA = dual-energy X-ray absorptiometry FFM = fat-free mass FFMI = fat-free mass index FM = fat mass HbA1c = glycated hemoglobin A1c MAO = metabolically abnormal obesity MHO = metabolically healthy obesity MS = metabolic syndrome OR = odds ratio T2D = type 2 diabetes WC = waist circumference

How to get fat: nutritional mechanisms of seasonal fat accumulation in migratory songbirds

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Bairlein, Franz

2002-01-01

Many migratory birds accumulate large amounts of lipids as the prime energy source for their long-distance flights. This fat accumulation is mostly under endogenous control, reflecting genetically programmed temporal shifts of the body mass set point. It is accompanied by an increase in daily food intake and food utilisation efficiency and by a seasonal shift in food selection. In particular, seasonal frugivory appears to play a key role in many migrants. Fruits have a high content of fatty acids indispensable for building up the specific depot lipids. In addition, plant secondary compounds seem to play some kind of supportive role, but the mechanisms are not yet known. The effect of being fat on the metabolic situation in migrant birds appears to be similar to the metabolic syndrome in obese humans. The fat migratory bird provides a model through which to study nutritional factors as well as the biochemical and endocrine regulation of food intake, body mass and obesity.

Depot-Specific Changes in Fat Metabolism with Aging in a Type 2 Diabetic Animal Model.

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Se Eun Park

Full Text Available Visceral fat accretion is a hallmark of aging and is associated with aging-induced metabolic dysfunction. PPARγ agonist was reported to improve insulin sensitivity by redistributing fat from visceral fat to subcutaneous fat. The purpose of this study was to investigate the underlying mechanisms by which aging affects adipose tissue remodeling in a type 2 diabetic animal model and through which PPARγ activation modulates aging-related fat tissue distribution. At the ages of 21, 31 and 43 weeks, OLETF rats as an animal model of type 2 diabetes were evaluated for aging-related effects on adipose tissue metabolism in subcutaneous and visceral fat depots. During aging, the ratio of visceral fat weight to subcutaneous fat weight (V/S ratio increased. Aging significantly increased the mRNA expression of genes involved in lipogenesis such as lipoprotein lipase, fatty acid binding protein aP2, lipin 1, and diacylglycerol acyltransferase 1, which were more prominent in visceral fat than subcutaneous fat. The mRNA expression of adipose triglyceride lipase, which is involved in basal lipolysis and fatty acid recycling, was also increased, more in visceral fat compared to subcutaneous fat during aging. The mRNA levels of the genes associated with lipid oxidation were increased, whereas the mRNA levels of genes associated with energy expenditure showed no significant change during aging. PPARγ agonist treatment in OLETF rats resulted in fat redistribution with a decreasing V/S ratio and improved glucose intolerance. The genes involved in lipogenesis decreased in visceral fat of the PPARγ agonist-treated rats. During aging, fat distribution was changed by stimulating lipid uptake and esterification in visceral fat rather than subcutaneous fat, and by altering the lipid oxidation.

Depot-Specific Changes in Fat Metabolism with Aging in a Type 2 Diabetic Animal Model.

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Park, Se Eun; Park, Cheol-Young; Choi, Jung Mook; Chang, Eugene; Rhee, Eun-Jung; Lee, Won-Young; Oh, Ki Won; Park, Sung Woo; Kang, Eun Seok; Lee, Hyun Chul; Cha, Bong Soo

2016-01-01

Visceral fat accretion is a hallmark of aging and is associated with aging-induced metabolic dysfunction. PPARγ agonist was reported to improve insulin sensitivity by redistributing fat from visceral fat to subcutaneous fat. The purpose of this study was to investigate the underlying mechanisms by which aging affects adipose tissue remodeling in a type 2 diabetic animal model and through which PPARγ activation modulates aging-related fat tissue distribution. At the ages of 21, 31 and 43 weeks, OLETF rats as an animal model of type 2 diabetes were evaluated for aging-related effects on adipose tissue metabolism in subcutaneous and visceral fat depots. During aging, the ratio of visceral fat weight to subcutaneous fat weight (V/S ratio) increased. Aging significantly increased the mRNA expression of genes involved in lipogenesis such as lipoprotein lipase, fatty acid binding protein aP2, lipin 1, and diacylglycerol acyltransferase 1, which were more prominent in visceral fat than subcutaneous fat. The mRNA expression of adipose triglyceride lipase, which is involved in basal lipolysis and fatty acid recycling, was also increased, more in visceral fat compared to subcutaneous fat during aging. The mRNA levels of the genes associated with lipid oxidation were increased, whereas the mRNA levels of genes associated with energy expenditure showed no significant change during aging. PPARγ agonist treatment in OLETF rats resulted in fat redistribution with a decreasing V/S ratio and improved glucose intolerance. The genes involved in lipogenesis decreased in visceral fat of the PPARγ agonist-treated rats. During aging, fat distribution was changed by stimulating lipid uptake and esterification in visceral fat rather than subcutaneous fat, and by altering the lipid oxidation.

Lipasin, a novel nutritionally-regulated liver-enriched factor that regulates serum triglyceride levels.

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Zhang, Ren

2012-08-10

The metabolic syndrome, a common disorder including glucose intolerance and dyslipidemia, poses a major public health issue. Patients with high blood lipids, such as triglycerides, are at high risk in developing atherosclerotic cardiovascular diseases. To identify genes involved in metabolism, we performed RNA-seq experiments on the liver and fat in mice treated with a high-fat diet or fasting, and identified Gm6484 (named Lipasin) as a novel nutritionally regulated gene. Human LIPASIN is liver specific, while the mouse one is enriched in the liver and fat, including both brown and white adipose tissues. Obesity increases liver Lipasin, whereas fasting reduces its expression in fat. ANGPTL3 (Angiopoietin-like 3) and ANGPTL4 are critical regulators of blood lipids. LIPASIN shares homology with ANGPTL3's N-terminal domain that is needed for lipid regulation, and with ANGPTL4's N-terminal segment that mediates lipoprotein lipase (LPL) binding. Lipasin overexpression by adenoviruses in mice increases serum triglyceride levels, and a recombinant Lipasin inhibits LPL activity. Therefore, a potential mechanism for Lipasin-mediated triglyceride elevation is through reduced triglyceride clearance by LPL inhibition. Lipasin is thus a novel nutritionally-regulated liver-enriched factor that plays a role in lipid metabolism. Copyright © 2012 Elsevier Inc. All rights reserved.

Maternal fat-soluble vitamins, brain development, and regulation of feeding behavior: an overview of research.

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Sánchez-Hernández, Diana; Anderson, G Harvey; Poon, Abraham N; Pannia, Emanuela; Cho, Clara E; Huot, Pedro S P; Kubant, Ruslan

2016-10-01

Recent research shows a link between vitamin intake during pregnancy and offspring health. Inadequate intakes of water-soluble vitamins during pregnancy lead to obesity and characteristics of the metabolic syndrome, concurrent with altered developments in food intake regulatory pathways. Few studies, however, have reported on the effects of fat-soluble vitamins (A, D, E, and K) on the development of food intake regulatory pathways. The majority of studies to date have focused on associations between inadequate and high intakes of folic acid and vitamin D and neurocognitive development of the offspring. Hence, the objective of this review is to present an evaluation of the role of maternal vitamins A, D, E, and K in brain development and function of neural pathways that regulate feeding behaviors. PubMed and Google Scholar were searched from 1975 through September, 2016. Most studies supporting a role for fat-soluble vitamins in regulating brain development and associated behaviors have been conducted in animal and cell models, leaving uncertain their relevance to neurocognitive development and function in humans. Nevertheless, although current research on defining the role of maternal fat-soluble vitamins in offspring's brain development is limited, it is sufficient to warrant further investigations on their impact when intake amounts during pregnancy are not only inadequate but also exceed requirements. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of different exercise protocols on metabolic profiles and fatty acid metabolism in skeletal muscle in high-fat diet-fed rats.

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Shen, Youqing; Xu, Xiangfeng; Yue, Kai; Xu, Guodong

2015-05-01

To evaluate the efficacy of mild-intensity endurance, high-intensity interval, and concurrent exercise on preventing high-fat diet-induced obesity. Male rats were divided into five groups, control diet/sedentary group, high-fat diet/sedentary, high-fat diet/endurance exercise, high-fat diet/interval exercise (HI), and high-fat diet/concurrent exercise. All exercise groups were made to exercise for 10 weeks, with matched running distances. Body weight, fat content, blood metabolites, quantitative insulin sensitivity check index (QUICKI), and adipocyte and liver lipid droplet size were assessed, and the expression of fatty acid metabolism-related genes was quantified. All exercise protocols reduced body weight, adiposity, serum triglycerides, and fasting glucose and also improved QUICKI to some extent. However, only HI prevented obesity and its associated pathologies completely. The expression of stearoyl-coenzyme A desaturase-1 was elevated in all rats fed a high-fat diet whereas carnitine palmitoyltransferase 1 (CPT1) expression was increased with exercise. Rev-erbα expression was elevated only in the HI group, which also had the highest level of CPT1 expression. The HI-induced increase in Rev-erbα and CPT1 expression was associated with the complete prevention of diet-induced obesity. Moreover, the increased caloric expenditure achieved with this protocol was preferential over other exercise regimens, and might be used to improve lipid metabolism. © 2015 The Obesity Society.

Genome-wide mapping of Quantitative Trait Loci for fatness, fat cell characteristics and fat metabolism in three porcine F2 crosses

Czech Academy of Sciences Publication Activity Database

Geldermann, H.; Čepica, Stanislav; Stratil, Antonín; Bartenschlager, H.; Preuss, S.

2010-01-01

Roč. 42, č. 31 (2010), s. 1-16 ISSN 0999-193X R&D Projects: GA ČR GA523/07/0353; GA ČR(CZ) GA523/06/1302 Institutional research plan: CEZ:AV0Z50450515 Keywords : fat metabolism * porcine * genome mapping Subject RIV: GI - Animal Husbandry ; Breeding Impact factor: 1.484, year: 2010

Neuropeptide Y acts directly in the periphery on fat tissue and mediates stress-induced obesity and metabolic syndrome.

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Kuo, Lydia E; Kitlinska, Joanna B; Tilan, Jason U; Li, Lijun; Baker, Stephen B; Johnson, Michael D; Lee, Edward W; Burnett, Mary Susan; Fricke, Stanley T; Kvetnansky, Richard; Herzog, Herbert; Zukowska, Zofia

2007-07-01

The relationship between stress and obesity remains elusive. In response to stress, some people lose weight, whereas others gain. Here we report that stress exaggerates diet-induced obesity through a peripheral mechanism in the abdominal white adipose tissue that is mediated by neuropeptide Y (NPY). Stressors such as exposure to cold or aggression lead to the release of NPY from sympathetic nerves, which in turn upregulates NPY and its Y2 receptors (NPY2R) in a glucocorticoid-dependent manner in the abdominal fat. This positive feedback response by NPY leads to the growth of abdominal fat. Release of NPY and activation of NPY2R stimulates fat angiogenesis, macrophage infiltration, and the proliferation and differentiation of new adipocytes, resulting in abdominal obesity and a metabolic syndrome-like condition. NPY, like stress, stimulates mouse and human fat growth, whereas pharmacological inhibition or fat-targeted knockdown of NPY2R is anti-angiogenic and anti-adipogenic, while reducing abdominal obesity and metabolic abnormalities. Thus, manipulations of NPY2R activity within fat tissue offer new ways to remodel fat and treat obesity and metabolic syndrome.

Tocotrienols Reverse Cardiovascular, Metabolic and Liver Changes in High Carbohydrate, High Fat Diet-Fed Rats

Directory of Open Access Journals (Sweden)

Weng-Yew Wong

2012-10-01

Full Text Available Tocotrienols have been reported to improve lipid profiles, reduce atherosclerotic lesions, decrease blood glucose and glycated haemoglobin concentrations, normalise blood pressure in vivo and inhibit adipogenesis in vitro, yet their role in the metabolic syndrome has not been investigated. In this study, we investigated the effects of palm tocotrienol-rich fraction (TRF on high carbohydrate, high fat diet-induced metabolic, cardiovascular and liver dysfunction in rats. Rats fed a high carbohydrate, high fat diet for 16 weeks developed abdominal obesity, hypertension, impaired glucose and insulin tolerance with increased ventricular stiffness, lower systolic function and reduced liver function. TRF treatment improved ventricular function, attenuated cardiac stiffness and hypertension, and improved glucose and insulin tolerance, with reduced left ventricular collagen deposition and inflammatory cell infiltration. TRF improved liver structure and function with reduced plasma liver enzymes, inflammatory cell infiltration, fat vacuoles and balloon hepatocytes. TRF reduced plasma free fatty acid and triglyceride concentrations but only omental fat deposition was decreased in the abdomen. These results suggest that tocotrienols protect the heart and liver, and improve plasma glucose and lipid profiles with minimal changes in abdominal obesity in this model of human metabolic syndrome.

Understanding Regulation of Metabolism through Feasibility Analysis

NARCIS (Netherlands)

Nikerel, I.E.; Berkhout, J.; Hu, F.; Teusink, B.; Reinders, M.J.T.; De Ridder, D.

2012-01-01

Understanding cellular regulation of metabolism is a major challenge in systems biology. Thus far, the main assumption was that enzyme levels are key regulators in metabolic networks. However, regulation analysis recently showed that metabolism is rarely controlled via enzyme levels only, but

Insulin-dependent glucose metabolism in dairy cows with variable fat mobilization around calving.

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Weber, C; Schäff, C T; Kautzsch, U; Börner, S; Erdmann, S; Görs, S; Röntgen, M; Sauerwein, H; Bruckmaier, R M; Metges, C C; Kuhla, B; Hammon, H M

2016-08-01

Dairy cows undergo significant metabolic and endocrine changes during the transition from pregnancy to lactation, and impaired insulin action influences nutrient partitioning toward the fetus and the mammary gland. Because impaired insulin action during transition is thought to be related to elevated body condition and body fat mobilization, we hypothesized that over-conditioned cows with excessive body fat mobilization around calving may have impaired insulin metabolism compared with cows with low fat mobilization. Nineteen dairy cows were grouped according to their average concentration of total liver fat (LFC) after calving in low [LLFC; LFC 24.4% total fat/DM; n=10) fat-mobilizing cows. Blood samples were taken from wk 7 antepartum (ap) to wk 5 postpartum (pp) to determine plasma concentrations of glucose, insulin, glucagon, and adiponectin. We applied euglycemic-hyperinsulinemic (EGHIC) and hyperglycemic clamps (HGC) in wk 5 ap and wk 3 pp to measure insulin responsiveness in peripheral tissue and pancreatic insulin secretion during the transition period. Before and during the pp EGHIC, [(13)C6] glucose was infused to determine the rate of glucose appearance (GlucRa) and glucose oxidation (GOx). Body condition, back fat thickness, and energy-corrected milk were greater, but energy balance was lower in HLFC than in LLFC. Plasma concentrations of glucose, insulin, glucagon, and adiponectin decreased at calving, and this was followed by an immediate increase of glucagon and adiponectin after calving. Insulin concentrations ap were higher in HLFC than in LLFC cows, but the EGHIC indicated no differences in peripheral insulin responsiveness among cows ap and pp. However, GlucRa and GOx:GlucRa during the pp EGHIC were greater in HLFC than in LLFC cows. During HGC, pancreatic insulin secretion was lower, but the glucose infusion rate was higher pp than ap in both groups. Plasma concentrations of nonesterified fatty acids decreased during HGC and EGHIC, but in both

Hormonal regulation of lipid metabolism in developing coho salmon, Oncorhynchus kisutch

International Nuclear Information System (INIS)

Sheridan, M.A.

1985-01-01

Lipid metabolism in juvenile coho salmon is characterized, and adaptive changes in lipid mobilization are described in relation to development and hormonal influences. The rates of lipogenesis and lipolysis were determined in selected tissues of juvenile salmon during the period of seawater preadaptive development (smoltification). Neutral lipid (sterol) and fatty acid synthesis in the liver and mesenteric fat was measured by tritium incorporation. Fatty acid synthesis in the liver and mesenteric fat decreased by 88% and 81%, respectively, between late February (parr) and early June (smolt). To assess the role of hormones in smoltification-associated lipid depletion, growth hormone, prolactin, thyroxin and cortisol were administered in vivo early in development (parr) to determine if any of these factors could initiate the metabolic responses normally seen later in development (smolt). Growth hormone stimulated lipid mobilization from coho salmon parr. Prolactin strongly stimulated lipid mobilization in coho parr. Thyroxin and cortisol also stimulated lipid mobilization for coho salmon parr. The direct effect of hormones was studied by in vitro pH-stat incubation of liver slices. These data suggest that norepinephrine stimulates fatty acid release via β-adrenergic pathways. Somatostatin and its partial analogue from the fish caudal neurosecretory system, urotensin II, also affect lipid mobilization. These results establish the presence of hormone-sensitive lipase in salmon liver and suggest that the regulation of lipid metabolism in salmon involves both long-acting and short-acting hormonal agents

DEPTOR in POMC neurons affects liver metabolism but is dispensable for the regulation of energy balance.

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Caron, Alexandre; Labbé, Sébastien M; Mouchiroud, Mathilde; Huard, Renaud; Lanfray, Damien; Richard, Denis; Laplante, Mathieu

2016-06-01

We have recently demonstrated that specific overexpression of DEP-domain containing mTOR-interacting protein (DEPTOR) in the mediobasal hypothalamus (MBH) protects mice against high-fat diet-induced obesity, revealing DEPTOR as a significant contributor to energy balance regulation. On the basis of evidence that DEPTOR is expressed in the proopiomelanocortin (POMC) neurons of the MBH, the present study aimed to investigate whether these neurons mediate the metabolic effects of DEPTOR. Here, we report that specific DEPTOR overexpression in POMC neurons does not recapitulate any of the phenotypes observed when the protein was overexpressed in the MBH. Unlike the previous model, mice overexpressing DEPTOR only in POMC neurons 1) did not show differences in feeding behavior, 2) did not exhibit changes in locomotion activity and oxygen consumption, 3) did not show an improvement in systemic glucose metabolism, and 4) were not resistant to high-fat diet-induced obesity. These results support the idea that other neuronal populations are responsible for these phenotypes. Nonetheless, we observed a mild elevation in fasting blood glucose, insulin resistance, and alterations in liver glucose and lipid homeostasis in mice overexpressing DEPTOR in POMC neurons. Taken together, these results show that DEPTOR overexpression in POMC neurons does not affect energy balance regulation but could modulate metabolism through a brain-liver connection. Copyright © 2016 the American Physiological Society.

High-fat diet reprograms the epigenome of rat spermatozoa and transgenerationally affects metabolism of the offspring

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de Castro Barbosa, Thais; Ingerslev, Lars R; Alm, Petter S

2016-01-01

OBJECTIVES: Chronic and high consumption of fat constitutes an environmental stress that leads to metabolic diseases. We hypothesized that high-fat diet (HFD) transgenerationally remodels the epigenome of spermatozoa and metabolism of the offspring. METHODS: F0-male rats fed either HFD or chow diet......1 male offspring showed common DNA methylation and small non-coding RNA expression signatures. Altered expression of sperm miRNA let-7c was passed down to metabolic tissues of the offspring, inducing a transcriptomic shift of the let-7c predicted targets. CONCLUSION: Our results provide insight...... into mechanisms by which HFD transgenerationally reprograms the epigenome of sperm cells, thereby affecting metabolic tissues of offspring throughout two generations....

AMP-regulated protein kinase activity in the hearts of mice treated with low- or high-fat diet measured using novel LC-MS method.

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Rybakowska, I M; Slominska, E M; Romaszko, P; Olkowicz, M; Kaletha, K; Smolenski, R T

2015-06-01

AMP-regulated protein kinase (AMPK) is involved in regulation of energy-generating pathways in response to the metabolic needs in different organs including the heart. The activity of AMPK is mainly controlled by AMP concentration that in turn could be affected by nucleotide metabolic pathways. This study aimed to develop a procedure for measurement of AMPK activity together with nucleotide metabolic enzymes and its application for studies of mice treated with high-fat diet. The method developed was based on analysis of conversion of AMARA peptide to pAMARA by partially purified heart homogenate by liquid chromatography/mass spectrometry (LC/MS). Activities of the enzymes of nucleotide metabolism were evaluated by analysis of conversion of substrates into products by HPLC. The method was applied for analysis of hearts of mice fed 12 weeks with low- (LFD) or high-fat diet (HFD). The optimized method for AMPK activity analysis (measured in presence of AMP) revealed change of activity from 0.089 ± 0.035 pmol/min/mg protein in LFD to 0.024 ± 0.002 in HFD. This coincided with increase of adenosine deaminase (ADA) activity from 0.11 ± 0.02 to 0.19 ± 0.06 nmol/mg tissue/min and decrease of AMP-deaminase (AMPD) activity from 1.26 ± 0.35 to 0.56 ± 0.15 nmol/mg tissue/min for LFD and HFD, respectively. We have proven quality of our LC/MS method for analysis of AMPK activity. We observed decrease in AMPK activity in the heart of mice treated with high-fat diet. However, physiological consequences of this change could be modulated by decrease in AMPD activity.

Effects of TiO2 nanoparticles on nutrition metabolism in silkworm fat body

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J. H. Tian

2016-06-01

Full Text Available Silkworm (Bombyx mori is an important economic insect with a fat body that plays a crucial role in the storage and transfer of nutrients. It is also known that TiO2 nanoparticles (NPs can improve feed efficiency and promote silk protein synthesis in the silkworm. In this study, we profiled gene expression in the silkworm fat body after TiO2 NP treatment, validated the major RNA-seq findings, and determined the contents of trehalose and triglyceride, the activity of lipase, and the amount of total proteins. RNA-seq analysis revealed that TiO2 NP treatment caused significant expression changes in 341 genes (P≤0.01, 138 of which were upregulated while the other 203 were downregulated. The expression levels of two target genes in the insulin signaling pathway and two protein metabolism-related target genes, three lipid metabolism-associated target genes, two carbohydrate metabolism related target genes and expression levels of seven heat shock protein genes were increased, and that of threonine dehydratase gene and fatty acid transport protein gene were decreased. The RNA-seq results of 16 genes were validated by quantitative real-time PCR. The lipase activity, content of trehalose, and amount of total proteins were elevated by 3.86-fold, 1.34-fold, and 1.21-fold, respectively, and the content of triglyceride was decreased by 0.94-fold after TiO2 NP treatment. These results indicated that TiO2 NPs activated the insulin signaling pathway, promoted the metabolism of protein, fat, and carbohydrate, and improved nutrition metabolism. Our study provides new support for the understanding of the beneficial effect of TiO2 NPs on silkworm nutrient metabolism.

Dynamic regulation of hepatic lipid droplet properties by diet.

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Crunk, Amanda E; Monks, Jenifer; Murakami, Aya; Jackman, Matthew; Maclean, Paul S; Ladinsky, Mark; Bales, Elise S; Cain, Shannon; Orlicky, David J; McManaman, James L

2013-01-01

Cytoplasmic lipid droplets (CLD) are organelle-like structures that function in neutral lipid storage, transport and metabolism through the actions of specific surface-associated proteins. Although diet and metabolism influence hepatic CLD levels, how they affect CLD protein composition is largely unknown. We used non-biased, shotgun, proteomics in combination with metabolic analysis, quantitative immunoblotting, electron microscopy and confocal imaging to define the effects of low- and high-fat diets on CLD properties in fasted-refed mice. We found that the hepatic CLD proteome is distinct from that of CLD from other mammalian tissues, containing enzymes from multiple metabolic pathways. The hepatic CLD proteome is also differentially affected by dietary fat content and hepatic metabolic status. High fat feeding markedly increased the CLD surface density of perilipin-2, a critical regulator of hepatic neutral lipid storage, whereas it reduced CLD levels of betaine-homocysteine S-methyltransferase, an enzyme regulator of homocysteine levels linked to fatty liver disease and hepatocellular carcinoma. Collectively our data demonstrate that the hepatic CLD proteome is enriched in metabolic enzymes, and that it is qualitatively and quantitatively regulated by diet and metabolism. These findings implicate CLD in the regulation of hepatic metabolic processes, and suggest that their properties undergo reorganization in response to hepatic metabolic demands.

Exercise reverses metabolic syndrome in high-fat diet-induced obese rats.

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Touati, Sabeur; Meziri, Fayçal; Devaux, Sylvie; Berthelot, Alain; Touyz, Rhian M; Laurant, Pascal

2011-03-01

Chronic consumption of a high-fat diet induces obesity. We investigated whether exercise would reverse the cardiometabolic disorders associated with obesity without it being necessary to change from a high- to normal-fat diet. Sprague-Dawley rats were placed on a high-fat (HFD) or control diet (CD) for 12 wk. HFD rats were then divided into four groups: sedentary HFD (HFD-S), exercise trained (motor treadmill for 12 wk) HFD (HFD-Ex), modified diet (HFD to CD; HF/CD-S), and exercise trained with modified diet (HF/CD-Ex). Cardiovascular risk parameters associated with metabolic syndrome were measured, and contents of aortic Akt, phospho-Akt at Ser (473), total endothelial nitric oxide synthase (eNOS), and phospho-eNOS at Ser (1177) were determined by Western blotting. Chronic consumption of HFD induced a metabolic syndrome. Exercise and dietary modifications reduced adiposity, improved glucose and insulin levels and plasma lipid profile, and exerted an antihypertensive effect. Exercise was more effective than dietary modification in improving plasma levels of thiobarbituric acid-reacting substance and in correcting the endothelium-dependent relaxation to acetylcholine and insulin. Furthermore, independent of the diet used, exercise increased Akt and eNOS phosphorylation. Metabolic syndrome induced by HFD is reversed by exercise and diet modification. It is demonstrated that exercise training induces these beneficial effects without the requirement for dietary modification, and these beneficial effects may be mediated by shear stress-induced Akt/eNOS pathway activation. Thus, exercise may be an effective strategy to reverse almost all the atherosclerotic risk factors linked to obesity, particularly in the vasculature.

Influence on bone metabolism of dietary trace elements, protein, fat, carbohydrates, and vitamins.

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Sarazin, M; Alexandre, C; Thomas, T

2000-01-01

Osteoporosis is a multifactorial disease driven primarily by the genetic factors that control bone metabolism. Among environmental factors, diet may play a key role, affording a target for low-cost intervention. Calcium and vitamin D are well known to affect bone metabolism. Other nutrients may influence bone mass changes; for instance, a number of trace elements and vitamins other than vitamin D are essential to many of the steps of bone metabolism. A wide variety of foods provide these nutrients, and in industrialized countries deficiencies are more often due to idiosyncratic eating habits than to cultural influences. Both culture and vogue influence the amount of carbohydrate, fat, and protein in the typical diet. In children, the current trend is to reduce protein and to increase carbohydrate and fat. Data from epidemiological and animal studies suggest that this may adversely affect bone mass and the fracture risk.

Bile acids are important direct and indirect regulators of the secretion of appetite- and metabolism-regulating hormones from the gut and pancreas

DEFF Research Database (Denmark)

Kuhre, Rune Ehrenreich; Albrechtsen, Nicolai Jacob Wewer; Larsen, Olav

2018-01-01

), and glucagon-like peptide-1 (GLP-1), but also glucagon and insulin in vivo, to levels comparable to those resulting from glucose stimulation. The mechanisms of GLP-1, neurotensin, and peptide YY (PYY) secretion was secondary to intestinal absorption and depended on activation of basolateral membrane Takeda G......OBJECTIVE: Bile acids (BAs) facilitate fat absorption and may play a role in glucose and metabolism regulation, stimulating the secretion of gut hormones. The relative importance and mechanisms involved in BA-stimulated secretion of appetite and metabolism regulating hormones from the gut...... and pancreas is not well described and was the purpose of this study. METHODS: The effects of bile acids on the secretion of gut and pancreatic hormones was studied in rats and compared to the most well described nutritional secretagogue: glucose. The molecular mechanisms that underlie the secretion...

dSir2 in the Adult Fat Body, but Not in Muscles, Regulates Life Span in a Diet-Dependent Manner

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Kushal Kr. Banerjee

2012-12-01

Full Text Available Sir2, an evolutionarily conserved NAD+-dependent deacetylase, has been implicated as a key factor in mediating organismal life span. However, recent contradictory findings have brought into question the role of Sir2 and its orthologs in regulating organismal longevity. In this study, we report that Drosophila Sir2 (dSir2 in the adult fat body regulates longevity in a diet-dependent manner. We used inducible Gal4 drivers to knock down and overexpress dSir2 in a tissue-specific manner. A diet-dependent life span phenotype of dSir2 perturbations (both knockdown and overexpression in the fat body, but not muscles, negates the effects of background genetic mutations. In addition to providing clarity to the field, our study contrasts the ability of dSir2 in two metabolic tissues to affect longevity. We also show that dSir2 knockdown abrogates fat-body dFOXO-dependent life span extension. This report highlights the importance of the interplay between genetic factors and dietary inputs in determining organismal life spans.

Liver fat content in type 2 diabetes: relationship with hepatic perfusion and substrate metabolism

NARCIS (Netherlands)

Rijzewijk, Luuk J.; van der Meer, Rutger W.; Lubberink, Mark; Lamb, Hildo J.; Romijn, Johannes A.; de Roos, Albert; Twisk, Jos W.; Heine, Robert J.; Lammertsma, Adriaan A.; Smit, Johannes W. A.; Diamant, Michaela

2010-01-01

Hepatic steatosis is common in type 2 diabetes. It is causally linked to the features of the metabolic syndrome, liver cirrhosis, and cardiovascular disease. Experimental data have indicated that increased liver fat may impair hepatic perfusion and metabolism. The aim of the current study was to

High intake of regular-fat cheese compared with reduced-fat cheese does not affect LDL cholesterol or risk markers of the metabolic syndrome

DEFF Research Database (Denmark)

Raziani, Farinaz; Tholstrup, Tine; Kristensen, Marlene Dahlwad

2016-01-01

was to compare the effects of regular-fat cheese with an equal amount of reduced-fat cheese and an isocaloric amount of carbohydrate-rich foods on LDL cholesterol and risk factors for the metabolic syndrome (MetS). DESIGN: The study was a 12-wk randomized parallel intervention preceded by a 2-wk run-in period...

Dendrobium nobile Lindl. alkaloids regulate metabolism gene expression in livers of mice.

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Xu, Yun-Yan; Xu, Ya-Sha; Wang, Yuan; Wu, Qin; Lu, Yuan-Fu; Liu, Jie; Shi, Jing-Shan

2017-10-01

In our previous studies, Dendrobium nobile Lindl. alkaloids (DNLA) has been shown to have glucose-lowering and antihyperlipidaemia effects in diabetic rats, in rats fed with high-fat diets, and in mice challenged with adrenaline. This study aimed to examine the effects of DNLA on the expression of glucose and lipid metabolism genes in livers of mice. Mice were given DNLA at doses of 10-80 mg/kg, po for 8 days, and livers were removed for total RNA and protein isolation to perform real-time RT-PCR and Western blot analysis. Dendrobium nobile Lindl. alkaloids increased PGC1α at mRNA and protein levels and increased glucose metabolism gene Glut2 and FoxO1 expression. DNLA also increased the expression of fatty acid β-oxidation genes Acox1 and Cpt1a. The lipid synthesis regulator Srebp1 (sterol regulatory element-binding protein-1) was decreased, while the lipolysis gene ATGL was increased. Interestingly, DNLA increased the expression of antioxidant gene metallothionein-1 and NADPH quinone oxidoreductase-1 (Nqo1) in livers of mice. Western blot on selected proteins confirmed these changes including the increased expression of GLUT4 and PPARα. DNLA has beneficial effects on liver glucose and lipid metabolism gene expressions, and enhances the Nrf2-antioxidant pathway gene expressions, which could play integrated roles in regulating metabolic disorders. © 2017 Royal Pharmaceutical Society.

Insights into the Melipona scutellaris (Hymenoptera, Apidae, Meliponini) fat body transcriptome.

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de Sousa, Cristina Soares; Serrão, José Eduardo; Bonetti, Ana Maria; Amaral, Isabel Marques Rodrigues; Kerr, Warwick Estevam; Maranhão, Andréa Queiroz; Ueira-Vieira, Carlos

2013-07-01

The insect fat body is a multifunctional organ analogous to the vertebrate liver. The fat body is involved in the metabolism of juvenile hormone, regulation of environmental stress, production of immunity regulator-like proteins in cells and protein storage. However, very little is known about the molecular mechanisms involved in fat body physiology in stingless bees. In this study, we analyzed the transcriptome of the fat body from the stingless bee Melipona scutellaris. In silico analysis of a set of cDNA library sequences yielded 1728 expressed sequence tags (ESTs) and 997 high-quality sequences that were assembled into 29 contigs and 117 singlets. The BLAST X tool showed that 86% of the ESTs shared similarity with Apis mellifera (honeybee) genes. The M. scutellaris fat body ESTs encoded proteins with roles in numerous physiological processes, including anti-oxidation, phosphorylation, metabolism, detoxification, transmembrane transport, intracellular transport, cell proliferation, protein hydrolysis and protein synthesis. This is the first report to describe a transcriptomic analysis of specific organs of M. scutellaris. Our findings provide new insights into the physiological role of the fat body in stingless bees.

Farnesoid X Receptor as a homeostat for hepatic nutrient metabolism, proliferation and intestinal inflammation : Novel insights into mechanisms of regulation

NARCIS (Netherlands)

Massafra, V

2017-01-01

Our body hosts several molecules that function as hormones to regulate metabolism in the liver. Bile acids (BAs) are molecules produced by the liver and stored in the gall bladder. After eating a meal, BAs are secreted in the intestine, where they help the digestion of fats and vitamins.

Effects of ferulic acid and γ-oryzanol on high-fat and high-fructose diet-induced metabolic syndrome in rats.

Science.gov (United States)

Wang, Ou; Liu, Jia; Cheng, Qian; Guo, Xiaoxuan; Wang, Yong; Zhao, Liang; Zhou, Feng; Ji, Baoping

2015-01-01

The high morbidity of metabolic dysfunction diseases has heightened interest in seeking natural and safe compounds to maintain optimal health. γ-Oryzanol (OZ), the ferulic acid (FA) ester with phytosterols, mainly present in rice bran has been shown to improve markers of metabolic syndrome. This study investigates the effects of FA and OZ on alleviating high-fat and high-fructose diet (HFFD)-induced metabolic syndrome parameters. Male SD rats were fed with a regular rodent diet, HFFD, or HFFD supplemented with 0.05% FA or 0.16% OZ (equimolar concentrations) for 13 weeks. Food intake, organ indices, serum lipid profiles, glucose metabolism, insulin resistance (IR) index and cytokine levels were analyzed. The mechanisms were further investigated in oleic acid-stimulated HepG2 cells by analyzing triglyceride (TG) content and lipogenesis-related gene expressions. In the in vivo study, FA and OZ exhibited similar effects in alleviating HFFD-induced obesity, hyperlipidemia, hyperglycemia, and IR. However, only OZ treatment significantly decreased liver index and hepatic TG content, lowered serum levels of C-reactive protein and IL-6, and increased serum concentration of adiponectin. In the in vitro assay, only OZ administration significantly inhibited intracellular TG accumulation and down-regulated expression of stearoyl coenzyme-A desaturase-1, which might facilitate OZ to enhance its hepatoprotective effect. OZ is more effective than FA in inhibiting hepatic fat accumulation and inflammation. Thus, FA and OZ could be used as dietary supplements to alleviate the deleterious effects of HFFD.

Effects of ferulic acid and γ-oryzanol on high-fat and high-fructose diet-induced metabolic syndrome in rats.

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Ou Wang

Full Text Available The high morbidity of metabolic dysfunction diseases has heightened interest in seeking natural and safe compounds to maintain optimal health. γ-Oryzanol (OZ, the ferulic acid (FA ester with phytosterols, mainly present in rice bran has been shown to improve markers of metabolic syndrome. This study investigates the effects of FA and OZ on alleviating high-fat and high-fructose diet (HFFD-induced metabolic syndrome parameters.Male SD rats were fed with a regular rodent diet, HFFD, or HFFD supplemented with 0.05% FA or 0.16% OZ (equimolar concentrations for 13 weeks. Food intake, organ indices, serum lipid profiles, glucose metabolism, insulin resistance (IR index and cytokine levels were analyzed. The mechanisms were further investigated in oleic acid-stimulated HepG2 cells by analyzing triglyceride (TG content and lipogenesis-related gene expressions.In the in vivo study, FA and OZ exhibited similar effects in alleviating HFFD-induced obesity, hyperlipidemia, hyperglycemia, and IR. However, only OZ treatment significantly decreased liver index and hepatic TG content, lowered serum levels of C-reactive protein and IL-6, and increased serum concentration of adiponectin. In the in vitro assay, only OZ administration significantly inhibited intracellular TG accumulation and down-regulated expression of stearoyl coenzyme-A desaturase-1, which might facilitate OZ to enhance its hepatoprotective effect.OZ is more effective than FA in inhibiting hepatic fat accumulation and inflammation. Thus, FA and OZ could be used as dietary supplements to alleviate the deleterious effects of HFFD.

miR-182 Regulates Metabolic Homeostasis by Modulating Glucose Utilization in Muscle

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Duo Zhang

2016-07-01

Full Text Available Understanding the fiber-type specification and metabolic switch in skeletal muscle provides insights into energy metabolism in physiology and diseases. Here, we show that miR-182 is highly expressed in fast-twitch muscle and negatively correlates with blood glucose level. miR-182 knockout mice display muscle loss, fast-to-slow fiber-type switching, and impaired glucose metabolism. Mechanistic studies reveal that miR-182 modulates glucose utilization in muscle by targeting FoxO1 and PDK4, which control fuel selection via the pyruvate dehydrogenase complex (PDHC. Short-term high-fat diet (HFD feeding reduces muscle miR-182 levels by tumor necrosis factor α (TNFα, which contributes to the upregulation of FoxO1/PDK4. Restoration of miR-182 expression in HFD-fed mice induces a faster muscle phenotype, decreases muscle FoxO1/PDK4 levels, and improves glucose metabolism. Together, our work establishes miR-182 as a critical regulator that confers robust and precise controls on fuel usage and glucose homeostasis. Our study suggests that a metabolic shift toward a faster and more glycolytic phenotype is beneficial for glucose control.

Dlk1/FA1 Is a Novel Endocrine Regulator of Bone and Fat Mass and Its Serum Level Is Modulated By Growth Hormone

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Abdallah, B.M.; Ding, M.; Jensen, C.H.

2007-01-01

Fat and bone metabolism are two linked processes regulated by several hormonal factors. FA1 (fetal antigen 1) is the soluble form of dlk1 (delta like 1), which is a member of the Notch-Delta family. We have previously identified FA1 as a negative regulator of bone marrow mesenchymal stem cell...... differentiation. Here, we studied the effects of circulating FA1 on fat and bone mass in vivo by generating mice expressing high serum levels of FA1 (FA1-mice) using the hydrodynamic-based gene transfer procedure (HGTP). We found that increased serum FA1 levels led to a significant reduction in total body weight......, fat mass and bone mass in a dose-dependent manner. Reduced bone mass in FA1-mice was associated with the inhibition of mineral apposition rate and bone formation rates by 58% and 72% respectively. Since FA1 is co-localized with growth hormone (GH) in the pituitary gland, we explored the possible...

Dlk1/FA1 is a novel endocrine regulator of bone and fat mass and its serum level is modulated by growth hormone

DEFF Research Database (Denmark)

Abdallah, Basem; Ding, Ming; Jensen, Charlotte H

2007-01-01

Fat and bone metabolism are two linked processes regulated by several hormonal factors. Fetal antigen 1 (FA1) is the soluble form of dlk1 (delta-like 1), which is a member of the Notch-Delta family. We previously identified FA1 as a negative regulator of bone marrow mesenchymal stem cell...... differentiation. Here, we studied the effects of circulating FA1 on fat and bone mass in vivo by generating mice expressing high serum levels of FA1 (FA1 mice) using the hydrodynamic-based gene transfer procedure. We found that increased serum FA1 levels led to a significant reduction in total body weight, fat...... mass, and bone mass in a dose-dependent manner. Reduced bone mass in FA1 mice was associated with the inhibition of mineral apposition rate and bone formation rates by 58 and 72%, respectively. Because FA1 is colocalized with GH in the pituitary gland, we explored the possible modulation of serum FA1...

Clerodendron glandulosum Coleb., Verbenaceae, ameliorates high fat diet-induced alteration in lipid and cholesterol metabolism in rats

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RN Jadeja

Full Text Available The present study was undertaken to evaluate the efficacy of freeze dried extract of Clerodendron glandulosum Coleb., Verbenaceae, leaves (FECG on alteration in lipid and cholesterol metabolism in high fat diet fed hyperlipidemic rats. Plasma and hepatic lipid profiles, lipid and cholesterol metabolizing enzymes in target tissues and fecal total lipids and bile acid contents were evaluated in FECG treated normolipidemic and hyperlipidemic rats. These results were compared with synthetic hypolipidemic drug Lovastatin (LVS. Results indicate that FECG was able to positively regulate induced experimental hyperlipidemia by significant alteration in plasma and tissue lipid profiles. These results can be attributed to reduced absorption, effective elimination and augmented catabolism of lipids and cholesterol possibly due to high content of saponin and phytosterols in C. glandulosum. Use of C. glandulosum extract as a potential therapeutic agent against hypercholesterolemia and hypertriglyceridemia is indicated.

Maternal high-fat diet induces metabolic stress response disorders in offspring hypothalamus.

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Nguyen, Long The; Saad, Sonia; Tan, Yi; Pollock, Carol; Chen, Hui

2017-07-01

Maternal obesity has been shown to increase the risk of obesity and related disorders in the offspring, which has been partially attributed to changes of appetite regulators in the offspring hypothalamus. On the other hand, endoplasmic reticulum (ER) stress and autophagy have been implicated in hypothalamic neuropeptide dysregulation, thus may also play important roles in such transgenerational effect. In this study, we show that offspring born to high-fat diet-fed dams showed significantly increased body weight and glucose intolerance, adiposity and plasma triglyceride level at weaning. Hypothalamic mRNA level of the orexigenic neuropeptide Y (NPY) was increased, while the levels of the anorexigenic pro-opiomelanocortin (POMC), NPY1 receptor (NPY1R) and melanocortin-4 receptor (MC4R) were significantly downregulated. In association, the expression of unfolded protein response (UPR) markers including glucose-regulated protein (GRP)94 and endoplasmic reticulum DNA J domain-containing protein (Erdj)4 was reduced. By contrast, protein levels of autophagy-related genes Atg5 and Atg7, as well as mitophagy marker Parkin, were slightly increased. The administration of 4-phenyl butyrate (PBA), a chemical chaperone of protein folding and UPR activator, in the offspring from postnatal day 4 significantly reduced their body weight, fat deposition, which were in association with increased activating transcription factor (ATF)4, immunoglobulin-binding protein (BiP) and Erdj4 mRNA as well as reduced Parkin, PTEN-induced putative kinase (PINK)1 and dynamin-related protein (Drp)1 protein expression levels. These results suggest that hypothalamic ER stress and mitophagy are among the regulatory factors of offspring metabolic changes due to maternal obesity. © 2017 Society for Endocrinology.

Maternal High-Fat and High-Salt Diets Have Differential Programming Effects on Metabolism in Adult Male Rat Offspring

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Stephanie A. Segovia

2018-03-01

Full Text Available Maternal high-fat or high-salt diets can independently program adverse cardiometabolic outcomes in offspring. However, there is a paucity of evidence examining their effects in combination on metabolic function in adult offspring. Female Sprague Dawley rats were randomly assigned to either: control (CD; 10% kcal from fat, 1% NaCl, high-salt (SD; 10% kcal from fat, 4% NaCl, high-fat (HF; 45% kcal from fat, 1% NaCl or high-fat and salt (HFSD; 45% kcal from fat, 4% NaCl diets 21 days prior to mating and throughout pregnancy and lactation. Male offspring were weaned onto a standard chow diet and were culled on postnatal day 130 for plasma and tissue collection. Adipocyte histology and adipose tissue, liver, and gut gene expression were examined in adult male offspring. HF offspring had significantly greater body weight, impaired insulin sensitivity and hyperleptinemia compared to CD offspring, but these increases were blunted in HFSD offspring. HF offspring had moderate adipocyte hypertrophy and increased expression of the pre-adipocyte marker Dlk1. There was a significant effect of maternal salt with increased hepatic expression of Dgat1 and Igfb2. Gut expression of inflammatory (Il1r1, Tnfα, Il6, and Il6r and renin–angiotensin system (Agtr1a, Agtr1b markers was significantly reduced in HFSD offspring compared to HF offspring. Therefore, salt mitigates some adverse offspring outcomes associated with a maternal HF diet, which may be mediated by altered adipose tissue morphology and gut inflammatory and renin–angiotensin regulation.

SIRT1 and metabolic syndrome

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Katarzyna Mac-Marcjanek

2011-04-01

Full Text Available Both obesity and type 2 diabetes mellitus, two major components of metabolic syndrome, become healthepidemics in the world. Over the past decade, advances in understanding the role of some regulators participatingin lipid and carbohydrate homeostasis have been made.Of them, SIRT1, the mammalian orthologue of the yeast Sir2 protein has been identified. SIRT1 is a nuclearNAD+-dependent deacetylase that targets many transcriptional modulators, including PPAR-α and -γ (peroxisomeproliferator-activated receptors α and γ, PGC-1α (PPAR-γ coactivator-1α, FOXO (forkhead box O proteins,and nuclear factor κB (NF-κB, thereby this enzyme mediates a wide range of physiological processes like apoptosis,fat metabolism, glucose homeostasis, and neurodegeneration.In this article, we discuss how SIRT1 regulates lipid and carbohydrate metabolism, and insulin secretion indifferent metabolic organs/tissue, including liver, muscle, pancreas, and fat. Additionally, the role of this enzymein reduction of inflammatory signalling is highlighted.

FAT/CD36: a major regulator of neuronal fatty acid sensing and energy homeostasis in rats and mice.

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Le Foll, Christelle; Dunn-Meynell, Ambrose; Musatov, Serguei; Magnan, Christophe; Levin, Barry E

2013-08-01

Hypothalamic "metabolic-sensing" neurons sense glucose and fatty acids (FAs) and play an integral role in the regulation of glucose, energy homeostasis, and the development of obesity and diabetes. Using pharmacologic agents, we previously found that ~50% of these neurons responded to oleic acid (OA) by using the FA translocator/receptor FAT/CD36 (CD36). For further elucidation of the role of CD36 in neuronal FA sensing, ventromedial hypothalamus (VMH) CD36 was depleted using adeno-associated viral (AAV) vector expressing CD36 short hairpin RNA (shRNA) in rats. Whereas their neuronal glucosensing was unaffected by CD36 depletion, the percent of neurons that responded to OA was decreased specifically in glucosensing neurons. A similar effect was seen in total-body CD36-knockout mice. Next, weanling rats were injected in the VMH with CD36 AAV shRNA. Despite significant VMH CD36 depletion, there was no effect on food intake, body weight gain, or total carcass adiposity on chow or 45% fat diets. However, VMH CD36-depleted rats did have increased plasma leptin and subcutaneous fat deposition and markedly abnormal glucose tolerance. These results demonstrate that CD36 is a critical factor in both VMH neuronal FA sensing and the regulation of energy and glucose homeostasis.

Hypothalamic PGC-1α Protects Against High-Fat Diet Exposure by Regulating ERα

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Eugenia Morselli

2014-10-01

Full Text Available High-fat diets (HFDs lead to obesity and inflammation in the central nervous system (CNS. Estrogens and estrogen receptor α (ERα protect premenopausal females from the metabolic complications of inflammation and obesity-related disease. Here, we demonstrate that hypothalamic PGC-1α regulates ERα and inflammation in vivo. HFD significantly increased palmitic acid (PA and sphingolipids in the CNS of male mice when compared to female mice. PA, in vitro, and HFD, in vivo, reduced PGC-1α and ERα in hypothalamic neurons and astrocytes of male mice and promoted inflammation. PGC-1α depletion with ERα overexpression significantly inhibited PA-induced inflammation, confirming that ERα is a critical determinant of the anti-inflammatory response. Physiologic relevance of ERα-regulated inflammation was demonstrated by reduced myocardial function in male, but not female, mice following chronic HFD exposure. Our findings show that HFD/PA reduces PGC-1α and ERα, promoting inflammation and decrements in myocardial function in a sex-specific way.

Hypothalamic PGC-1α protects against high-fat diet exposure by regulating ERα.

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Morselli, Eugenia; Fuente-Martin, Esther; Finan, Brian; Kim, Min; Frank, Aaron; Garcia-Caceres, Cristina; Navas, Carlos Rodriguez; Gordillo, Ruth; Neinast, Michael; Kalainayakan, Sarada P; Li, Dan L; Gao, Yuanqing; Yi, Chun-Xia; Hahner, Lisa; Palmer, Biff F; Tschöp, Matthias H; Clegg, Deborah J

2014-10-23

High-fat diets (HFDs) lead to obesity and inflammation in the central nervous system (CNS). Estrogens and estrogen receptor α (ERα) protect premenopausal females from the metabolic complications of inflammation and obesity-related disease. Here, we demonstrate that hypothalamic PGC-1α regulates ERα and inflammation in vivo. HFD significantly increased palmitic acid (PA) and sphingolipids in the CNS of male mice when compared to female mice. PA, in vitro, and HFD, in vivo, reduced PGC-1α and ERα in hypothalamic neurons and astrocytes of male mice and promoted inflammation. PGC-1α depletion with ERα overexpression significantly inhibited PA-induced inflammation, confirming that ERα is a critical determinant of the anti-inflammatory response. Physiologic relevance of ERα-regulated inflammation was demonstrated by reduced myocardial function in male, but not female, mice following chronic HFD exposure. Our findings show that HFD/PA reduces PGC-1α and ERα, promoting inflammation and decrements in myocardial function in a sex-specific way.

Gold-quercetin nanoparticles prevent metabolic endotoxemia-induced kidney injury by regulating TLR4/NF-kB signaling and Nrf2 pathway in high fat diet fed mice

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Xu MX

2017-01-01

Full Text Available Min-Xuan Xu,1,2,* Ming Wang,3,* Wei-Wei Yang4 1Chongqing Key Laboratory of Medicinal Resources in the Three Gorges Reservoir Region, School of Biological and Chemical Engineering, Chongqing University of Education, Chongqing, 2College of Engineering and Applied Sciences, Nanjing University, Nanjing, 3Department of Urology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 4Department of Nephrology, Huai’an First People’s Hospital, Nanjing Medical University, Jiangsu, People’s Republic of China *These authors contributed equally to this work Abstract: High-fat diet-induced metabolic syndrome followed by chronic kidney disease caused by intestinal endotoxemia have received extensive attention. Toll-like receptor 4 (TLR4/nuclear factor-kappa B (NF-κB and oxidative stress-related Nrf2/Keap1 were regarded as the key target points involved in metabolic inflammation and kidney injury. However, the molecular mechanism of interaction between TLR4/NF-κB and Nrf2 activation in high-fat diet-induced renal injury is not absolutely understood. Quercetin, a natural product, has been reported to possess antitumor and anti-inflammatory effects. In this regard, this study attempted to prepare poly(d,l-lactide-co-glycolide-loaded gold nanoparticles precipitated with quercetin (GQ to investigate the anti-inflammatory and anti-oxidative stress effects in high-fat diet-induced kidney failure. For this study, C57BL/6 mice fed fat-rich fodder were used as the metabolic syndrome model to evaluate the protective effects of GQ on kidney injury and to determine whether TLR4/NF-κB and Nrf2 pathways were associated with the process. Moreover, histological examinations, enzyme-linked immunosorbent assay, Western blot, and basic blood tests and systemic inflammation-related indicators were used to investigate the inhibitory effects of GQ and underlying molecular mechanism by which it may reduce renal injury. Of note, podocyte

A conserved role for syndecan family members in the regulation of whole-body energy metabolism.

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Maria De Luca

2010-06-01

Full Text Available Syndecans are a family of type-I transmembrane proteins that are involved in cell-matrix adhesion, migration, neuronal development, and inflammation. Previous quantitative genetic studies pinpointed Drosophila Syndecan (dSdc as a positional candidate gene affecting variation in fat storage between two Drosophila melanogaster strains. Here, we first used quantitative complementation tests with dSdc mutants to confirm that natural variation in this gene affects variability in Drosophila fat storage. Next, we examined the effects of a viable dSdc mutant on Drosophila whole-body energy metabolism and associated traits. We observed that young flies homozygous for the dSdc mutation had reduced fat storage and slept longer than homozygous wild-type flies. They also displayed significantly reduced metabolic rate, lower expression of spargel (the Drosophila homologue of PGC-1, and reduced mitochondrial respiration. Compared to control flies, dSdc mutants had lower expression of brain insulin-like peptides, were less fecund, more sensitive to starvation, and had reduced life span. Finally, we tested for association between single nucleotide polymorphisms (SNPs in the human SDC4 gene and variation in body composition, metabolism, glucose homeostasis, and sleep traits in a cohort of healthy early pubertal children. We found that SNP rs4599 was significantly associated with resting energy expenditure (P = 0.001 after Bonferroni correction and nominally associated with fasting glucose levels (P = 0.01 and sleep duration (P = 0.044. On average, children homozygous for the minor allele had lower levels of glucose, higher resting energy expenditure, and slept shorter than children homozygous for the common allele. We also observed that SNP rs1981429 was nominally associated with lean tissue mass (P = 0.035 and intra-abdominal fat (P = 0.049, and SNP rs2267871 with insulin sensitivity (P = 0.037. Collectively, our results in Drosophila and humans argue that

Brown Fat and Browning for the Treatment of Obesity and Related Metabolic Disorders

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So Hun Kim

2016-01-01

Full Text Available Brown fat is a specialized fat depot that can increase energy expenditure and produce heat. After the recent discovery of the presence of active brown fat in human adults and novel transcription factors controlling brown adipocyte differentiation, the field of the study of brown fat has gained great interest and is rapidly growing. Brown fat expansion and/or activation results in increased energy expenditure and a negative energy balance in mice and limits weight gain. Brown fat is also able to utilize blood glucose and lipid and results in improved glucose metabolism and blood lipid independent of weight loss. Prolonged cold exposure and beta adrenergic agonists can induce browning of white adipose tissue. The inducible brown adipocyte, beige adipocyte evolving by thermogenic activation of white adipose tissue have different origin and molecular signature from classical brown adipocytes but share the characteristics of high mitochondria content, UCP1 expression and thermogenic capacity when activated. Increasing browning may also be an efficient way to increase whole brown fat activity. Recent human studies have shown possibilities that findings in mice can be reproduced in human, making brown fat a good candidate organ to treat obesity and its related disorders.

Relationship between abdominal fat area measured by screening abdominal fat CT and metabolic syndrome in asymptomatic Korean individuals

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Park, Dae Woong; Park, Noh Hyuck; Park, Ji Yeon; Kim, Seon Jeong [Dept. of Radiology, MyoungJi Hospital, Seonam University College of Medicine, Goyang (Korea, Republic of)

2017-07-15

The purpose of this study was to investigate the relationship between abdominal fat as assessed by abdominal fat CT and metabolic syndrome (MS), especially in asymptomatic Korean individuals. Retrospectively, a medical record analysis was performed in a total of 111 patients with screening abdominal fat CT. The data such as visceral fat (VF), subcutaneous fat (SF) and VF/SF were elicited by abdominal fat CT, and we analyzed the relationship of VF, SF, and VF/SF with MS and cardiovascular risk factors. In males, VF and SF had a positive correlation with many cardiovascular risk factors and MS, but VF was superior to SF. In females, VF, but not SF, had a positive correlation with some cardiovascular risk factors and MS. The cut-off values of VF and SF to predict MS, which were calculated by drawing receiver operating characteristic curves, were as follows: the cut-off value of VF in men: 136.50 cm{sup 2}, the cut-off value of SF in men: 159.50 cm{sup 2}, and the cut-off value of VF in women: 134.50 cm{sup 2}. In conclusion, VF accumulation was the best predictor of MS and it had a positive correlation with cardiovascular risk factors in both sexes. SF also had a significant association with MS, especially in men, although it was not superior to VF.

Relationship between abdominal fat area measured by screening abdominal fat CT and metabolic syndrome in asymptomatic Korean individuals

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Park, Dae Woong; Park, Noh Hyuck; Park, Ji Yeon; Kim, Seon Jeong

2017-01-01

The purpose of this study was to investigate the relationship between abdominal fat as assessed by abdominal fat CT and metabolic syndrome (MS), especially in asymptomatic Korean individuals. Retrospectively, a medical record analysis was performed in a total of 111 patients with screening abdominal fat CT. The data such as visceral fat (VF), subcutaneous fat (SF) and VF/SF were elicited by abdominal fat CT, and we analyzed the relationship of VF, SF, and VF/SF with MS and cardiovascular risk factors. In males, VF and SF had a positive correlation with many cardiovascular risk factors and MS, but VF was superior to SF. In females, VF, but not SF, had a positive correlation with some cardiovascular risk factors and MS. The cut-off values of VF and SF to predict MS, which were calculated by drawing receiver operating characteristic curves, were as follows: the cut-off value of VF in men: 136.50 cm"2, the cut-off value of SF in men: 159.50 cm"2, and the cut-off value of VF in women: 134.50 cm"2. In conclusion, VF accumulation was the best predictor of MS and it had a positive correlation with cardiovascular risk factors in both sexes. SF also had a significant association with MS, especially in men, although it was not superior to VF

Nutritional Factors Affecting Abdominal Fat Deposition in Poultry: A Review

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Fouad, A. M.; El-Senousey, H. K.

2014-01-01

The major goals of the poultry industry are to increase the carcass yield and to reduce carcass fatness, mainly the abdominal fat pad. The increase in poultry meat consumption has guided the selection process toward fast-growing broilers with a reduced feed conversion ratio. Intensive selection has led to great improvements in economic traits such as body weight gain, feed efficiency, and breast yield to meet the demands of consumers, but modern commercial chickens exhibit excessive fat accumulation in the abdomen area. However, dietary composition and feeding strategies may offer practical and efficient solutions for reducing body fat deposition in modern poultry strains. Thus, the regulation of lipid metabolism to reduce the abdominal fat content based on dietary composition and feeding strategy, as well as elucidating their effects on the key enzymes associated with lipid metabolism, could facilitate the production of lean meat and help to understand the fat-lowering effects of diet and different feeding strategies. PMID:25050050

Regulation of metabolism by dietary carbohydrates in two lines of rainbow trout divergently selected for muscle fat content.

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Kamalam, Biju Sam; Medale, Françoise; Kaushik, Sadasivam; Polakof, Sergio; Skiba-Cassy, Sandrine; Panserat, Stephane

2012-08-01

Previous studies in two rainbow trout lines divergently selected for lean (L) or fat (F) muscle suggested that they differ in their ability to metabolise glucose. In this context, we investigated whether genetic selection for high muscle fat content led to a better capacity to metabolise dietary carbohydrates. Juvenile trout from the two lines were fed diets with or without gelatinised starch (17.1%) for 10 weeks, after which blood, liver, muscle and adipose tissues were sampled. Growth rate, feed efficiency and protein utilisation were lower in the F line than in the L line. In both lines, intake of carbohydrates was associated with a moderate post-prandial hyperglycaemia, a protein sparing effect, an enhancement of nutrient (TOR-S6) signalling cascade and a decrease of energy-sensing enzyme (AMPK). Gene expression of hepatic glycolytic enzymes was higher in the F line fed carbohydrates compared with the L line, but concurrently transcripts for the gluconeogenic enzymes was also higher in the F line, possibly impairing glucose homeostasis. However, the F line showed a higher gene expression of hepatic enzymes involved in lipogenesis and fatty acid bioconversion, in particular with an increased dietary carbohydrate intake. Enhanced lipogenic potential coupled with higher liver glycogen content in the F line suggests better glucose storage ability than the L line. Overall, the present study demonstrates the changes in hepatic intermediary metabolism resulting from genetic selection for high muscle fat content and dietary carbohydrate intake without, however, any interaction for an improved growth or glucose utilisation in the peripheral tissues.

Concentrating carbohydrates before sleep improves feeding regulation and metabolic and inflammatory parameters in mice.

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Sofer, Sigal; Eliraz, Abraham; Madar, Zecharia; Froy, Oren

2015-10-15

New evidance highlights the importance of food timing. Recently, we showed that a low-calorie diet with carbohydrates eaten mostly at dinner changed diurnal hormone secretion and led to greater weight loss and improved metabolic status in obese people. Herein, we set out to test whether concentrated-carbohydrates diet (CCD), in which carbohydrates are fed only before sleep, leads to an improved metabolic status in mouse hypothalamus and peripheral tissues. Diet-induced obese mice were given concentrated or distributed carbohydrate diet for 6 weeks. Obese mice fed CCD ate 8.3% less, were 9.3% leaner and had 39.7% less fat mass. Leptin, ghrelin and adiponectin displayed altered secretion. In addition, these mice exhibited an improved biochemical and inflammatory status. In the hypothalamus, anorexigenic signals were up-regulated and orexigenic signals were down-regulated. In peripheral tissues, CCD promoted adiponectin signaling, repressed gluconeogenesis, enhanced lipid oxidation and lowered inflammation, thus ameliorating the major risk factors of obesity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Effects of dietary heme iron and exercise training on abdominal fat accumulation and lipid metabolism in high-fat diet-fed mice.

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Katsumura, Masanori; Takagi, Shoko; Oya, Hana; Tamura, Shohei; Saneyasu, Takaoki; Honda, Kazuhisa; Kamisoyama, Hiroshi

2017-08-01

Animal by-products can be recycled and used as sources of essential nutrients. Water-soluble heme iron (WSHI), a functional food additive for supplementing iron, is produced by processing animal blood. In this study, we investigated the effects of dietary supplementation of 3% WSHI and exercise training for 4 weeks on the accumulation of abdominal fat and lipid metabolism in mice fed high-fat diet. Exercise-trained mice had significantly less perirenal adipose tissue, whereas WSHI-fed mice tended to have less epididymal adipose tissue. In addition, total weight of abdominal adipose tissues was significantly decreased in the Exercise + WSHI group. Dietary WSHI significantly increased the messenger RNA (mRNA) levels of lipoprotein lipase and hormone-sensitive lipase. WSHI-fed mice also tended to show increased mRNA levels of adipose triglyceride lipase in their epididymal adipose tissue. Dietary WSHI also significantly decreased the mRNA levels of fatty acid oxidation-related enzymes in the liver, but did not influence levels in the Gastrocnemius muscle. Exercise training did not influence the mRNA levels of lipid metabolism-related enzymes in the epididymal adipose tissue, liver or the Gastrocnemius muscle. These findings suggest that the accumulation of abdominal fat can be efficiently decreased by the combination of dietary WSHI and exercise training in mice fed high-fat diet. © 2016 Japanese Society of Animal Science.

Impact of short-term high-fat feeding on glucose and insulin metabolism in young healthy men

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Brøns, Charlotte; Jensen, Christine B.; Storgaard, Heidi

2009-01-01

A high-fat, high-calorie diet is associated with obesity and type 2 diabetes. However, the relative contribution of metabolic defects to the development of hyperglycaemia and type 2 diabetes is controversial. Accumulation of excess fat in muscle and adipose tissue in insulin resistance and type 2...

A high fat diet alters metabolic and bioenergetic function in the brain: A magnetic resonance spectroscopy study.

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Raider, Kayla; Ma, Delin; Harris, Janna L; Fuentes, Isabella; Rogers, Robert S; Wheatley, Joshua L; Geiger, Paige C; Yeh, Hung-Wen; Choi, In-Young; Brooks, William M; Stanford, John A

2016-07-01

Diet-induced obesity and associated metabolic effects can lead to neurological dysfunction and increase the risk of developing Alzheimer's disease (AD) and Parkinson's disease (PD). Despite these risks, the effects of a high-fat diet on the central nervous system are not well understood. To better understand the mechanisms underlying the effects of high fat consumption on brain regions affected by AD and PD, we used proton magnetic resonance spectroscopy ((1)H-MRS) to measure neurochemicals in the hippocampus and striatum of rats fed a high fat diet vs. normal low fat chow. We detected lower concentrations of total creatine (tCr) and a lower glutamate-to-glutamine ratio in the hippocampus of high fat rats. Additional effects observed in the hippocampus of high fat rats included higher N-acetylaspartylglutamic acid (NAAG), and lower myo-inositol (mIns) and serine (Ser) concentrations. Post-mortem tissue analyses revealed lower phosphorylated AMP-activated protein kinase (pAMPK) in the striatum but not in the hippocampus of high fat rats. Hippocampal pAMPK levels correlated significantly with tCr, aspartate (Asp), phosphoethanolamine (PE), and taurine (Tau), indicating beneficial effects of AMPK activation on brain metabolic and energetic function, membrane turnover, and edema. A negative correlation between pAMPK and glucose (Glc) indicates a detrimental effect of brain Glc on cellular energy response. Overall, these changes indicate alterations in neurotransmission and in metabolic and bioenergetic function in the hippocampus and in the striatum of rats fed a high fat diet. Copyright © 2016 Elsevier Ltd. All rights reserved.

Age-dependent alterations of glucose clearance and homeostasis are temporally separated and modulated by dietary fat

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Damgaard, Mads Thue Fejerskov; Pærregaard, Simone I.; Søgaard, Ida

2018-01-01

Diet- and age-dependent changes in glucose regulation in mice occur, but the temporal development, mechanisms and influence of dietary fat source remain to be defined. We followed metabolic changes in three groups of mice including a low-fat diet (LFD) reference group and two high-fat, high-sucro...

Metabolic-flux dependent regulation of microbial physiology.

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Litsios, Athanasios; Ortega, Álvaro D; Wit, Ernst C; Heinemann, Matthias

2018-04-01

According to the most prevalent notion, changes in cellular physiology primarily occur in response to altered environmental conditions. Yet, recent studies have shown that changes in metabolic fluxes can also trigger phenotypic changes even when environmental conditions are unchanged. This suggests that cells have mechanisms in place to assess the magnitude of metabolic fluxes, that is, the rate of metabolic reactions, and use this information to regulate their physiology. In this review, we describe recent evidence for metabolic flux-sensing and flux-dependent regulation. Furthermore, we discuss how such sensing and regulation can be mechanistically achieved and present a set of new candidates for flux-signaling metabolites. Similar to metabolic-flux sensing, we argue that cells can also sense protein translation flux. Finally, we elaborate on the advantages that flux-based regulation can confer to cells. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Understanding Regulation of Metabolism through Feasibility Analysis

Science.gov (United States)

Nikerel, Emrah; Berkhout, Jan; Hu, Fengyuan; Teusink, Bas; Reinders, Marcel J. T.; de Ridder, Dick

2012-01-01

Understanding cellular regulation of metabolism is a major challenge in systems biology. Thus far, the main assumption was that enzyme levels are key regulators in metabolic networks. However, regulation analysis recently showed that metabolism is rarely controlled via enzyme levels only, but through non-obvious combinations of hierarchical (gene and enzyme levels) and metabolic regulation (mass action and allosteric interaction). Quantitative analyses relating changes in metabolic fluxes to changes in transcript or protein levels have revealed a remarkable lack of understanding of the regulation of these networks. We study metabolic regulation via feasibility analysis (FA). Inspired by the constraint-based approach of Flux Balance Analysis, FA incorporates a model describing kinetic interactions between molecules. We enlarge the portfolio of objectives for the cell by defining three main physiologically relevant objectives for the cell: function, robustness and temporal responsiveness. We postulate that the cell assumes one or a combination of these objectives and search for enzyme levels necessary to achieve this. We call the subspace of feasible enzyme levels the feasible enzyme space. Once this space is constructed, we can study how different objectives may (if possible) be combined, or evaluate the conditions at which the cells are faced with a trade-off among those. We apply FA to the experimental scenario of long-term carbon limited chemostat cultivation of yeast cells, studying how metabolism evolves optimally. Cells employ a mixed strategy composed of increasing enzyme levels for glucose uptake and hexokinase and decreasing levels of the remaining enzymes. This trade-off renders the cells specialized in this low-carbon flux state to compete for the available glucose and get rid of over-overcapacity. Overall, we show that FA is a powerful tool for systems biologists to study regulation of metabolism, interpret experimental data and evaluate hypotheses. PMID

Neuronal Calcium Signaling in Metabolic Regulation and Adaptation to Nutrient Stress.

Science.gov (United States)

Jayakumar, Siddharth; Hasan, Gaiti

2018-01-01

All organisms can respond physiologically and behaviorally to environmental fluxes in nutrient levels. Different nutrient sensing pathways exist for specific metabolites, and their inputs ultimately define appropriate nutrient uptake and metabolic homeostasis. Nutrient sensing mechanisms at the cellular level require pathways such as insulin and target of rapamycin (TOR) signaling that integrates information from different organ systems like the fat body and the gut. Such integration is essential for coordinating growth with development. Here we review the role of a newly identified set of integrative interneurons and the role of intracellular calcium signaling within these neurons, in regulating nutrient sensing under conditions of nutrient stress. A comparison of the identified Drosophila circuit and cellular mechanisms employed in this circuit, with vertebrate systems, suggests that the identified cell signaling mechanisms may be conserved for neural circuit function related to nutrient sensing by central neurons. The ideas proposed are potentially relevant for understanding the molecular basis of metabolic disorders, because these are frequently linked to nutritional stress.

Beneficial effects of metformin on energy metabolism and visceral fat volume through a possible mechanism of fatty acid oxidation in human subjects and rats.

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Ichiro Tokubuchi

Full Text Available Metformin is known to have a beneficial effect on body weight and body composition, although the precise mechanism has not been elucidated yet. The aim of this study is to investigate the effects of metformin on energy metabolism and anthropometric factors in both human subjects and rats.In human studies, metformin (1500mg/day was administered to 23 healthy subjects and 18 patients with type 2 diabetes for 2 weeks. Metabolic parameters and energy metabolism were measured during a meal tolerance test in the morning before and after the treatment of metformin. In animal studies, 13 weeks old SD rats were fed 25-26 g of standard chow only during 12-hours dark phase with either treated by metformin (2.5mg/ml in drinking water or not for 2 weeks, and metabolic parameters, anthropometric factors and energy metabolism together with expressions related to fat oxidation and adaptive thermogenesis were measured either in fasting or post-prandial state at 15 weeks old.Post-prandial plasma lactate concentration was significantly increased after the metformin treatment in both healthy subjects and diabetic patients. Although energy expenditure (EE did not change, baseline respiratory quotient (RQ was significantly decreased and post-prandial RQ was significantly increased vice versa following the metformin treatment in both groups. By the administration of metformin to SD rats for 2 weeks, plasma levels of lactate and pyruvate were significantly increased in both fasting and post-prandial states. RQ during a fasting state was significantly decreased in metformin-treated rats compared to controls with no effect on EE. Metformin treatment brought about a significant reduction of visceral fat mass compared to controls accompanied by an up-regulation of fat oxidation-related enzyme in the liver, UCP-1 in the brown adipose tissue and UCP-3 in the skeletal muscle.From the results obtained, beneficial effects of metformin on visceral fat reduction has been

Metabolic and oxidative stress markers in Wistar rats after 2?months on a high-fat diet

OpenAIRE

Auberval, Nathalie; Dal, St?phanie; Bietiger, William; Pinget, Michel; Jeandidier, Nathalie; Maillard-Pedracini, Elisa; Schini-Kerth, Val?rie; Sigrist, S?verine

2014-01-01

Background Metabolic syndrome is associated with an increased risk of cardiovascular and hepatic complications. Oxidative stress in metabolic tissues has emerged as a universal feature of metabolic syndrome and its co-morbidities. We aimed to develop a rapidly and easily induced model of metabolic syndrome in rats to evaluate its impact on plasma and tissue oxidative stress. Materials and methods Metabolic syndrome was induced in rats using a high-fat diet (HFD), and these rats were compared ...

Parametric recursive system identification and self-adaptive modeling of the human energy metabolism for adaptive control of fat weight.

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Őri, Zsolt P

2017-05-01

A mathematical model has been developed to facilitate indirect measurements of difficult to measure variables of the human energy metabolism on a daily basis. The model performs recursive system identification of the parameters of the metabolic model of the human energy metabolism using the law of conservation of energy and principle of indirect calorimetry. Self-adaptive models of the utilized energy intake prediction, macronutrient oxidation rates, and daily body composition changes were created utilizing Kalman filter and the nominal trajectory methods. The accuracy of the models was tested in a simulation study utilizing data from the Minnesota starvation and overfeeding study. With biweekly macronutrient intake measurements, the average prediction error of the utilized carbohydrate intake was -23.2 ± 53.8 kcal/day, fat intake was 11.0 ± 72.3 kcal/day, and protein was 3.7 ± 16.3 kcal/day. The fat and fat-free mass changes were estimated with an error of 0.44 ± 1.16 g/day for fat and -2.6 ± 64.98 g/day for fat-free mass. The daily metabolized macronutrient energy intake and/or daily macronutrient oxidation rate and the daily body composition change from directly measured serial data are optimally predicted with a self-adaptive model with Kalman filter that uses recursive system identification.

Investigation of Fat Metabolism during Antiobesity Interventions by Magnetic Resonance Imaging and Spectroscopy

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Arunima Pola

2014-01-01

Full Text Available The focus of current treatments for obesity is to reduce the body weight or visceral fat, which requires longer duration to show effect. In this study, we investigated the short-term changes in fat metabolism in liver, abdomen, and skeletal muscle during antiobesity interventions including Sibutramine treatment and diet restriction in obese rats using magnetic resonance imaging, magnetic resonance spectroscopy, and blood chemistry. Sibutramine is an antiobesity drug that results in weight loss by increasing satiety and energy expenditure. The Sibutramine-treated rats showed reduction of liver fat and intramyocellular lipids on day 3. The triglycerides (TG decreased on day 1 and 3 compared to baseline (day 0. The early response/nonresponse in different fat depots will permit optimization of treatment for better clinical outcome rather than staying with a drug for longer periods.

Concurrence of High Fat Diet and APOE Gene Induces Allele Specific Metabolic and Mental Stress Changes in an AD Model

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Yifat Segev

2016-09-01

Full Text Available Aging is the main risk factor for neurodegenerative diseases, including Alzheimer’s disease (AD. However, evidence indicates that the pathological process begins long before actual cognitive or pathological symptoms are apparent. The long asymptomatic phase and complex integration between genetic, environmental, and metabolic factors make it one of the most challenging diseases to understand and cure. In the present study, we asked whether an environmental factor such as high-fat diet would synergize with a genetic factor to affect the metabolic and cognitive state in the ApoE4 mouse model of AD. Our data suggest that a high-fat diet induces diabetes mellitus-like metabolism in ApoE4 mice, as well as changes in BACE1 protein levels between the two ApoE strains. Furthermore, high-fat diet induces anxiety in this AD mouse model. Our results suggest that young ApoE4 carriers are prone to psychological stress and metabolic abnormalities related to AD, which can easily be triggered via high-fat nutrition.

Variable liver fat concentration as a proxy for body fat mobilization postpartum has minor effects on insulin-induced changes in hepatic gene expression related to energy metabolism in dairy cows.

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Weber, C; Schäff, C T; Kautzsch, U; Börner, S; Erdmann, S; Bruckmaier, R M; Röntgen, M; Kuhla, B; Hammon, H M

2017-02-01

The liver plays a central role in adaptation for energy requirements around calving, and changes in the effects of insulin on hepatic energy metabolism contribute to metabolic adaptation in dairy cows. Hepatic insulin effects may depend on body fat mobilization. The objective of this study was to investigate the effects of insulin on the hepatic gene expression of enzymes involved in energy metabolism and factors related to nutrition partitioning in cows with high and low total liver fat concentration (LFC) after calving. Holstein cows were retrospectively grouped according to their LFC after calving as a proxy for body fat mobilization. Cows were classified as low (LLFC; LFC 24.4% fat/dry matter; n = 10) fat-mobilizing after calving. Euglycemic-hyperinsulinemic clamps [6 mU/(kg × min) of insulin for 6 h] were performed in wk 5 antepartum (ap) and wk 3 postpartum (pp). Before and at the end of the euglycemic-hyperinsulinemic clamps, liver biopsies were taken to measure the mRNA abundance of enzymes involved in carbohydrate and lipid metabolism, expression related to the somatotropic axis, and adrenergic and glucocorticoid receptors. The mRNA abundance of pyruvate carboxylase, cytosolic phosphoenolpyruvate carboxykinase (PEPCK; PCK1), acyl-CoA-dehydrogenase very long chain (ACADVL), and hydroxyl-methyl-glutaryl-CoA-synthase 1 increased, but the mRNA abundance of solute carrier family 2 (SLC2A2 and SLC2A4), growth hormone receptor 1A (GHR1A), insulin-like growth factor 1 (IGF1), sterol regulatory element binding factor 1, adrenoceptor α 1A, and glucocorticoid receptor decreased from ap to pp. Insulin treatment was associated with decreased PCK1, mitochondrial PEPCK, glucose-6-phosphatase, propionyl-CoA-carboxylase α, carnitine-palmitoyl-transferase 1A, ACADVL, and insulin receptor mRNA, but increased IGF1 and SLC2A4 mRNA ap and pp and GHR1A mRNA pp. The mRNA abundance of SLC2A4 was greater, and the mRNA abundance of GHR1A and IGF1 tended to be lower in LLFC than

Coenzyme Q Metabolism Is Disturbed in High Fat Diet-Induced Non Alcoholic Fatty Liver Disease in Rats

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Kathleen M Botham

2012-02-01

Full Text Available Oxidative stress is believed to be a major contributory factor in the development of non alcoholic fatty liver disease (NAFLD, the most common liver disorder worldwide. In this study, the effects of high fat diet-induced NAFLD on Coenzyme Q (CoQ metabolism and plasma oxidative stress markers in rats were investigated. Rats were fed a standard low fat diet (control or a high fat diet (57% metabolizable energy as fat for 18 weeks. The concentrations of total (reduced + oxidized CoQ9 were increased by > 2 fold in the plasma of animals fed the high fat diet, while those of total CoQ10 were unchanged. Reduced CoQ levels were raised, but oxidized CoQ levels were not, thus the proportion in the reduced form was increased by about 75%. A higher percentage of plasma CoQ9 as compared to CoQ10 was in the reduced form in both control and high fat fed rats. Plasma protein thiol (SH levels were decreased in the high fat-fed rats as compared to the control group, but concentrations of lipid hydroperoxides and low density lipoprotein (LDL conjugated dienes were unchanged. These results indicate that high fat diet-induced NAFLD in rats is associated with altered CoQ metabolism and increased protein, but not lipid, oxidative stress.

Cut-off value of body fat in association with metabolic syndrome in Thai peri- and postmenopausal women.

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Bintvihok, W; Chaikittisilpa, S; Panyakamlerd, K; Jaisamrarn, U; Taechakraichana, N

2013-06-01

Pathophysiologic changes during the menopause transition may contribute to the risk of metabolic syndrome (MetS). Body fat composition, particularly visceral fat, is highly associated with increased insulin resistance, abnormal carbohydrate metabolism and high blood pressure. We purposefully wished to determine the optimal cut-off values of body fat composition, including visceral fat, in order to predict MetS and to assess the prevalence of MetS in peri- and postmenopausal women. This cross-sectional study was conducted in a population-based, prospective cohort at the Menopause and Gynecology clinics, King Chulalongkorn Memorial Hospital. Body fat percentage and visceral fat rating were measured by a bioelectrical impedance analyzer (Tanita SC 330). MetS was diagnosed using the Harmonizing criteria of A Joint Interim Statement of IDF/NHLBI/AHA/WHF/IAS/IASO 2009. Receiver operating characteristic analyses were performed to determine the optimal cut-off values of body fat, visceral fat, waist circumference and body mass index to identify peri- and postmenopausal women at risk of MetS. Ninety-two perimenopausal and 446 postmenopausal women aged 40-60 years were recruited for the analyses. The optimal cut-off values for body fat percentage, visceral fat rating, waist circumference and body mass index for identifying women at risk of MetS were 34%, 7, 88 cm and 24 kg/m(2), respectively. The prevalence of MetS in this study was 27.9%. The optimal cut-off values to predict MetS of body fat percentage, visceral fat and waist circumference were established. Using the Harmonizing 2009 criteria, we found that approximately one out of four peri- and postmenopausal women in this study had MetS.

Dietary fat interacts with PCBs to induce changes in lipid metabolism in LDL receptor deficient mice

Energy Technology Data Exchange (ETDEWEB)

Hennig, B.; Reiterer, G.; Toborek, M.; Matveev, S.V.; Daugherty, A.; Smart, E. [Univ. of Kentucky, Lexington (United States); Robertson, L.W. [Univ. of Iowa, Iowa City (United States)

2004-09-15

From epidemiological studies, there is substantial evidence that cardiovascular diseases are linked to environmental pollution and that exposure to polycyclic and/or polyhalogenated aromatic hydrocarbons can lead to human cardiovascular toxicity. A major route of exposure to PCBs in humans is via oral ingestion of contaminated food products. Therefore, circulating environmental contaminants derived from diets, such as PCBs, are in intimate contact with the vascular endothelium. Endothelial activation and dysfunction is an important factor in the overall regulation of vascular lesion pathology. In addition to endothelial barrier dysfunction, another functional change in atherosclerosis is the activation of the endothelium that is manifested as an increase in the expression of specific cytokines and adhesion molecules. These cytokines and adhesion molecules are proposed to mediate the inflammatory aspects of the disease by regulating the vascular entry of leukocytes. Alterations in lipid profile and lipid metabolism as a result of exposure to PCBs may be important components of endothelial cell dysfunction. Little is known about the interaction of dietary fats and PCBs in the pathology of atherosclerosis. We have reported a significant disruption in endothelial barrier function when cells were exposed to linoleic acid. In the current study we aimed to demonstrate the PCB-fatty acid interaction in vivo and hypothesized that PCB toxicity can be modulated by the type of fat consumed.

Integrating miRNA and mRNA Expression Profiling Uncovers miRNAs Underlying Fat Deposition in Sheep

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Guangxian Zhou

2017-01-01

Full Text Available MicroRNAs (miRNAs are endogenous, noncoding RNAs that regulate various biological processes including adipogenesis and fat metabolism. Here, we adopted a deep sequencing approach to determine the identity and abundance of miRNAs involved in fat deposition in adipose tissues from fat-tailed (Kazakhstan sheep, KS and thin-tailed (Tibetan sheep, TS sheep breeds. By comparing HiSeq data of these two breeds, 539 miRNAs were shared in both breeds, whereas 179 and 97 miRNAs were uniquely expressed in KS and TS, respectively. We also identified 35 miRNAs that are considered to be putative novel miRNAs. The integration of miRNA-mRNA analysis revealed that miRNA-associated targets were mainly involved in the gene ontology (GO biological processes concerning cellular process and metabolic process, and miRNAs play critical roles in fat deposition through their ability to regulate fundamental pathways. These pathways included the MAPK signaling pathway, FoxO and Wnt signaling pathway, and focal adhesion. Taken together, our results define miRNA expression signatures that may contribute to fat deposition and lipid metabolism in sheep.

Epicardial adipose tissue is associated with visceral fat, metabolic syndrome, and insulin resistance in menopausal women.

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Fernández Muñoz, María J; Basurto Acevedo, Lourdes; Córdova Pérez, Nydia; Vázquez Martínez, Ana Laura; Tepach Gutiérrez, Nayive; Vega García, Sara; Rocha Cruz, Alberto; Díaz Martínez, Alma; Saucedo García, Renata; Zárate Treviño, Arturo; González Escudero, Eduardo Alberto; Degollado Córdova, José Antonio

2014-06-01

Epicardial adipose tissue has been associated with several obesity-related parameters and with insulin resistance. Echocardiographic assessment of this tissue is an easy and reliable marker of cardiometabolic risk. However, there are insufficient studies on the relationship between epicardial fat and insulin resistance during the postmenopausal period, when cardiovascular risk increases in women. The objective of this study was to examine the association between epicardial adipose tissue and visceral adipose tissue, waist circumference, body mass index, and insulin resistance in postmenopausal women. A cross sectional study was conducted in 34 postmenopausal women with and without metabolic syndrome. All participants underwent a transthoracic echocardiogram and body composition analysis. A positive correlation was observed between epicardial fat and visceral adipose tissue, body mass index, and waist circumference. The values of these correlations of epicardial fat thickness overlying the aorta-right ventricle were r = 0.505 (P < .003), r = 0.545 (P < .001), and r = 0.515 (P < .003), respectively. Epicardial adipose tissue was higher in postmenopausal women with metabolic syndrome than in those without this syndrome (mean [standard deviation], 544.2 [122.9] vs 363.6 [162.3] mm(2); P = .03). Epicardial fat thickness measured by echocardiography was associated with visceral adipose tissue and other obesity parameters. Epicardial adipose tissue was higher in postmenopausal women with metabolic syndrome. Therefore, echocardiographic assessment of epicardial fat may be a simple and reliable marker of cardiovascular risk in postmenopausal women. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

miR-30e-5p and miR-15a Synergistically Regulate Fatty Acid Metabolism in Goat Mammary Epithelial Cells via LRP6 and YAP1

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Zhi Chen

2016-11-01

Full Text Available MicroRNA (miRNA regulates the expression of genes and influences a series of biological processes, including fatty acid metabolism. We screened the expression of miRNA in goat mammary glands during peak-lactation and non-lactating (“dry” periods, and performed an in vitro study with goat mammary epithelial cells (GMEC prior to sequencing analysis. Results illustrated that miR-30e-5p and miR-15a were highly expressed. Utilizing a luciferase reporter assay and Western blot, low-density lipoprotein receptor-related protein 6 (LRP6 and Yes associated protein 1 (YAP1 genes were demonstrated to be a target of miR-30e-5p and miR-15a in GMEC. Moreover, we demonstrated that the overexpression of miR-30e-5p and miR-15a in GMEC promoted fat metabolism while their knockdown impaired fat metabolism. These findings extend the discovery of a key role of miR-30e-5p and miR-15a in mediating adipocyte differentiation by suggesting a role in promoting milk fat synthesis. In conclusion, our findings indicate that miR-30e-5p, together with miR-15a, represses expression of LRP6 and promotes fat metabolism in GMEC. The data expanded our knowledge on the function of miRNAs in milk fat metabolism and synthesis in ruminant mammary cells.

Effects of SH-reagents of different molecular size upon glucose metabolism in isolated rat fat cells

International Nuclear Information System (INIS)

Kather, H.; Simon, B.

1975-01-01

To study the role of membrane SH-groups in glucose transport of isolated rat fat cells we compared the effects of a small organic mercurial reagent p-CMB with those of a large p-CMB-derivative - p-CMB-Dextran, MW approximately 10,000 -. It could be shown that both compounds were of almost identical reactivity on fat cell homogenate metabolism. When applied to intact fat cells uncoupled p-CMB showed an 1) insulin-like enhancement of 14 C incorporation from (U- 14 C) glucose into CO 2 and triglyceride, 2) inhibition of the insulin-stimulatory effect on these parameters and 3) inhibition of basal glucose uptake dependent on the concentrations used. Identical concentrations of p-CMB-Dextran, however, failed to influence basal glucose uptake as well as the insulin mediated increase in glucose metabolism. (orig.) [de

Effects of SH-reagents of different molecular size upon glucose metabolism in isolated rat fat cells

Energy Technology Data Exchange (ETDEWEB)

Kather, H; Simon, B [Heidelberg Univ. (F.R. Germany). Klinisches Inst. fuer Herzinfarktforschung

1975-09-01

To study the role of membrane SH-groups in glucose transport of isolated rat fat cells we compared the effects of a small organic mercurial reagent p-CMB with those of a large p-CMB-derivative - p-CMB-Dextran, MW approximately 10,000 -. It could be shown that both compounds were of almost identical reactivity on fat cell homogenate metabolism. When applied to intact fat cells uncoupled p-CMB showed an 1) insulin-like enhancement of /sup 14/C incorporation from (U-/sup 14/C) glucose into CO/sub 2/ and triglyceride, 2) inhibition of the insulin-stimulatory effect on these parameters and 3) inhibition of basal glucose uptake dependent on the concentrations used. Identical concentrations of p-CMB-Dextran, however, failed to influence basal glucose uptake as well as the insulin mediated increase in glucose metabolism.

Percentage of Body Fat and Fat Mass Index as a Screening Tool for Metabolic Syndrome Prediction in Colombian University Students

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Robinson Ramírez-Vélez

2017-09-01

Full Text Available High body fat is related to metabolic syndrome (MetS in all ethnic groups. Based on the International Diabetes Federation (IDF definition of MetS, the aim of this study was to explore thresholds of body fat percentage (BF% and fat mass index (FMI for the prediction of MetS among Colombian University students. A cross-sectional study was conducted on 1687 volunteers (63.4% women, mean age = 20.6 years. Weight, waist circumference, serum lipids indices, blood pressure, and fasting plasma glucose were measured. Body composition was measured by bioelectrical impedance analysis (BIA and FMI was calculated. MetS was defined as including more than or equal to three of the metabolic abnormalities according to the IDF definition. Receiver operating curve (ROC analysis was used to determine optimal cut-off points for BF% and FMI in relation to the area under the curve (AUC, sensitivity, and specificity in both sexes. The overall prevalence of MetS was found to be 7.7%, higher in men than women (11.1% vs. 5.3%; p < 0.001. BF% and FMI were positively correlated to MetS components (p < 0.05. ROC analysis indicated that BF% and FMI can be used with moderate accuracy to identify MetS in university-aged students. BF% and FMI thresholds of 25.55% and 6.97 kg/m2 in men, and 38.95% and 11.86 kg/m2 in women, were found to be indicative of high MetS risk. Based on the IDF criteria, both indexes’ thresholds seem to be good tools to identify university students with unfavorable metabolic profiles.

Topographical body fat distribution links to amino acid and lipid metabolism in healthy obese women [corrected].

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Francois-Pierre J Martin

Full Text Available Visceral adiposity is increasingly recognized as a key condition for the development of obesity related disorders, with the ratio between visceral adipose tissue (VAT and subcutaneous adipose tissue (SAT reported as the best correlate of cardiometabolic risk. In this study, using a cohort of 40 obese females (age: 25-45 y, BMI: 28-40 kg/m(2 under healthy clinical conditions and monitored over a 2 weeks period we examined the relationships between different body composition parameters, estimates of visceral adiposity and blood/urine metabolic profiles. Metabonomics and lipidomics analysis of blood plasma and urine were employed in combination with in vivo quantitation of body composition and abdominal fat distribution using iDXA and computerized tomography. Of the various visceral fat estimates, VAT/SAT and VAT/total abdominal fat ratios exhibited significant associations with regio-specific body lean and fat composition. The integration of these visceral fat estimates with metabolic profiles of blood and urine described a distinct amino acid, diacyl and ether phospholipid phenotype in women with higher visceral fat. Metabolites important in predicting visceral fat adiposity as assessed by Random forest analysis highlighted 7 most robust markers, including tyrosine, glutamine, PC-O 44∶6, PC-O 44∶4, PC-O 42∶4, PC-O 40∶4, and PC-O 40∶3 lipid species. Unexpectedly, the visceral fat associated inflammatory profiles were shown to be highly influenced by inter-days and between-subject variations. Nevertheless, the visceral fat associated amino acid and lipid signature is proposed to be further validated for future patient stratification and cardiometabolic health diagnostics.

Intra-abdominal fat: Comparison of computed tomography fat ...

African Journals Online (AJOL)

Background: Intra-abdominal fat is an important factor in determining the metabolic syndrome/insulin resistance, and thus the risk of diabetes and ischaemic heart disease. Computed Tomography (CT) fat segmentation represents a defined method of quantifying intra-abdominal fat, with attendant radiation risks.

Effects of aerobic exercise training on serum sex hormone binding globulin, body fat index, and metabolic syndrome factors in obese postmenopausal women.

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Kim, Jong-Won; Kim, Do-Yeon

2012-12-01

The percentage of obese postmenopausal women with metabolic syndrome is rising, and physical factors associated with the metabolic syndrome prevalence or incidence are also rising, including high body mass index (BMI), visceral fat area (VFA), low plasma sex hormone-binding globulin (SHBG) levels, and low cardiorespiratory fitness. Therefore, we investigated the influence of aerobic exercise on SHBG, body fat index (BFI), and metabolic syndrome factors in obese postmenopausal Korean women. Thirty healthy postmenopausal, women aged 53.46 ± 2.4 years and with over 32% body fat, were randomly assigned to an aerobic exercise group (EX; n=15) or to a "nonexercise" control (Con; n=15) group. The primary outcome measurements were serum SHBG, lipid profiles, insulin levels, and metabolic syndrome factors. Secondary outcome measurements were body composition, VFA, blood pressure (BP), and homeostasis model assessment of insulin resistance (HOMA-IR). Posttraining body weight and BFI (Pmetabolic syndrome factors (Pexercise group but not in the control group. SHBG levels also showed a significant positive correlation with high-density lipoprotein cholesterol (HDL-C) and significant negative correlations withglucose, diastolic blood pressure, fat mass, BMI, and percent body fat (Pexercise improves body composition, SHBG, insulin levels, and metabolic syndrome factors. These findings suggest that in obesepostmenopausal Korean women, 16 weeks of aerobic exercise is effective for preventing the metabolic syndrome caused by obesity.

Effects of disturbed liver growth and oxidative stress of high-fat diet-fed dams on cholesterol metabolism in offspring mice.

Science.gov (United States)

Kim, Juyoung; Kim, Juhae; Kwon, Young Hye

2016-08-01

Changes in nutritional status during gestation and lactation have detrimental effects on offspring metabolism. Several animal studies have shown that maternal high-fat diet (HFD) can predispose the offspring to development of obesity and metabolic diseases, however the mechanisms underlying these transgenerational effects are poorly understood. Therefore, we examined the effect of maternal HFD consumption on metabolic phenotype and hepatic expression of involved genes in dams to determine whether any of these parameters were associated with the metabolic outcomes in the offspring. Female C57BL/6 mice were fed a low-fat diet (LFD: 10% calories from fat) or a high-fat diet (HFD: 45% calories from fat) for three weeks before mating, and during pregnancy and lactation. Dams and their male offspring were studied at weaning. Dams fed an HFD had significantly higher body and adipose tissue weights and higher serum triglyceride and cholesterol levels than dams fed an LFD. Hepatic lipid levels and mRNA levels of genes involved in lipid metabolism, including LXRα, SREBP-2, FXR, LDLR, and ABCG8 were significantly changed by maternal HFD intake. Significantly lower total liver DNA and protein contents were observed in dams fed an HFD, implicating the disturbed liver adaptation in the pregnancy-related metabolic demand. HFD feeding also induced significant oxidative stress in serum and liver of dams. Offspring of dams fed an HFD had significantly higher serum cholesterol levels, which were negatively correlated with liver weights of dams and positively correlated with hepatic lipid peroxide levels in dams. Maternal HFD consumption induced metabolic dysfunction, including altered liver growth and oxidative stress in dams, which may contribute to the disturbed cholesterol homeostasis in the early life of male mice offspring.

Metabolic Regulation of a Bacterial Cell System with Emphasis on Escherichia coli Metabolism

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Shimizu, Kazuyuki

2013-01-01

It is quite important to understand the overall metabolic regulation mechanism of bacterial cells such as Escherichia coli from both science (such as biochemistry) and engineering (such as metabolic engineering) points of view. Here, an attempt was made to clarify the overall metabolic regulation mechanism by focusing on the roles of global regulators which detect the culture or growth condition and manipulate a set of metabolic pathways by modulating the related gene expressions. For this, it was considered how the cell responds to a variety of culture environments such as carbon (catabolite regulation), nitrogen, and phosphate limitations, as well as the effects of oxygen level, pH (acid shock), temperature (heat shock), and nutrient starvation. PMID:25937963

Variations in insulin responsiveness in rat fat cells are due to metabolic differences rather than insulin binding

DEFF Research Database (Denmark)

Hansen, Finn Mølgård; Nilsson, Poul; Sonne, Ole

1983-01-01

-insulin to fat cells. Insulin binding was not correlated to the plasma insulin level which however was reflected in the lipoprotein lipase activity in the adipose tissue. In conclusion, these results indicate that variations in insulin responsiveness in fat cells are due to alterations in cellular metabolism...

Mixed model of dietary fat effect on postprandial glucose-insulin metabolism from carbohydrates in type 1 diabetes.

Science.gov (United States)

Yamamoto Noguchi, Claudia Cecilia; Kunikane, Noriaki; Hashimoto, Shogo; Furutani, Eiko

2015-08-01

In this study we introduce an extension of a previously developed model of glucose-insulin metabolism in type 1 diabetes (T1D) from carbohydrates that includes the effect of dietary fat on postprandial glycemia. We include two compartments that represent plasma triglyceride and nonesterified fatty acid (NEFA) concentration, in addition to a mathematical representation of delayed gastric emptying and insulin resistance, which are the most well-known effects of dietary fat metabolism. Simulation results show that postprandial glucose as well as lipid levels in our model approximates clinical data from T1D patients.

Cocaine's appetite for fat and the consequences on body weight.

Science.gov (United States)

Billing, Lawrence; Ersche, Karen D

2015-03-01

For many individuals in treatment for cocaine dependence, weight gain is a substantial problem during recovery. This weight gain causes significant distress and seems to increase the risk of relapse. The mechanisms underlying cocaine's effects on weight remain elusive. It is widely assumed that this weight gain reflects a metabolic or behavioural compensatory response to the cessation of cocaine use. Here we challenge this assumption and outline potential mechanisms by which chronic cocaine use produces disturbances in the regulation of fat intake and storage, through its effects on the central and peripheral nervous systems, specifically the sympathetic nervous system. We hypothesize that the cocaine-induced alteration in fat regulation results in cocaine users developing a pronounced appetite for fatty food but keeps their fat mass low. This altered fat appetite subsequently leads to excessive weight gain when individuals enter treatment and stop using cocaine. Our aim is to shed light on the neurobiological mechanisms that may underlie the alterations in eating and fat regulation in cocaine-dependent individuals, to open up potential new avenues to support these individuals in recovery.

Regulation of metabolic networks by small molecule metabolites

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Kanehisa Minoru

2007-03-01

Full Text Available Abstract Background The ability to regulate metabolism is a fundamental process in living systems. We present an analysis of one of the mechanisms by which metabolic regulation occurs: enzyme inhibition and activation by small molecules. We look at the network properties of this regulatory system and the relationship between the chemical properties of regulatory molecules. Results We find that many features of the regulatory network, such as the degree and clustering coefficient, closely match those of the underlying metabolic network. While these global features are conserved across several organisms, we do find local differences between regulation in E. coli and H. sapiens which reflect their different lifestyles. Chemical structure appears to play an important role in determining a compounds suitability for use in regulation. Chemical structure also often determines how groups of similar compounds can regulate sets of enzymes. These groups of compounds and the enzymes they regulate form modules that mirror the modules and pathways of the underlying metabolic network. We also show how knowledge of chemical structure and regulation could be used to predict regulatory interactions for drugs. Conclusion The metabolic regulatory network shares many of the global properties of the metabolic network, but often varies at the level of individual compounds. Chemical structure is a key determinant in deciding how a compound is used in regulation and for defining modules within the regulatory system.

Skeletal Muscle and Liver Lipidomics and the Regulation of FAT/CD36

DEFF Research Database (Denmark)

Jordy, Andreas Børsting

induced obesity in mice, we observed an increased muscle and liver lipid content, analyzed by mass spectrometry, concomitant with decreased glucose tolerance. We observed that treadmill exercise-training in high-fat fed mice resulted in a reduction in the lipid content in the liver, but not in muscle...... that the current worldwide obesity epidemic has resulted in the increased prevalence of “metabolic disease clusters”, including type 2 diabetes, fatty liver disease and dyslipidemia. Excessive plasma lipids can result in the accumulation of lipid metabolites at ectopic sites including skeletal muscle and liver...... during isolated muscle contractions. On the contrary, previous observations suggest that a permanent relocation of FAT/CD36 protein to the sarcolemma induces intracellular lipid accumulation, resulting in insulin resistance. Therefore, FAT/CD36 has been linked to insulin resistance. Whether increased FAT...

A Single Day of Excessive Dietary Fat Intake Reduces Whole-Body Insulin Sensitivity: The Metabolic Consequence of Binge Eating

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Siôn A. Parry

2017-07-01

Full Text Available Consuming excessive amounts of energy as dietary fat for several days or weeks can impair glycemic control and reduce insulin sensitivity in healthy adults. However, individuals who demonstrate binge eating behavior overconsume for much shorter periods of time; the metabolic consequences of such behavior remain unknown. The aim of this study was to determine the effect of a single day of high-fat overfeeding on whole-body insulin sensitivity. Fifteen young, healthy adults underwent an oral glucose tolerance test before and after consuming a high-fat (68% of total energy, high-energy (78% greater than daily requirements diet for one day. Fasting and postprandial plasma concentrations of glucose, insulin, non-esterified fatty acids, and triglyceride were measured and the Matsuda insulin sensitivity index was calculated. One day of high-fat overfeeding increased postprandial glucose area under the curve (AUC by 17.1% (p < 0.0001 and insulin AUC by 16.4% (p = 0.007. Whole-body insulin sensitivity decreased by 28% (p = 0.001. In conclusion, a single day of high-fat, overfeeding impaired whole-body insulin sensitivity in young, healthy adults. This highlights the rapidity with which excessive consumption of calories through high-fat food can impair glucose metabolism, and suggests that acute binge eating may have immediate metabolic health consequences for the individual.

Fat metabolism in formerly obese women

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Ranneries, C; Bülow, J; Buemann, B

1998-01-01

An impaired fat oxidation has been implicated to play a role in the etiology of obesity, but it is unclear to what extent impaired fat mobilization from adipose tissue or oxidation of fat is responsible. The present study aimed to examine fat mobilization from adipose tissue and whole body fat...... oxidation stimulated by exercise in seven formerly obese women (FO) and eight matched controls (C). Lipolysis in the periumbilical subcutaneous adipose tissue, whole body energy expenditure (EE), and substrate oxidation rates were measured before, during, and after a 60-min bicycle exercise bout of moderate.......32 +/- 0.84 vs. 3.70 +/- 0.57 kJ/min, P obese group. In conclusion, fat mobilization both at rest and during exercise is intact in FO, whereas fat oxidation...

A buoyancy-based screen of Drosophila larvae for fat-storage mutants reveals a role for Sir2 in coupling fat storage to nutrient availability.

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Tânia Reis

2010-11-01

Full Text Available Obesity has a strong genetic component, but few of the genes that predispose to obesity are known. Genetic screens in invertebrates have the potential to identify genes and pathways that regulate the levels of stored fat, many of which are likely to be conserved in humans. To facilitate such screens, we have developed a simple buoyancy-based screening method for identifying mutant Drosophila larvae with increased levels of stored fat. Using this approach, we have identified 66 genes that when mutated increase organismal fat levels. Among these was a sirtuin family member, Sir2. Sirtuins regulate the storage and metabolism of carbohydrates and lipids by deacetylating key regulatory proteins. However, since mammalian sirtuins function in many tissues in different ways, it has been difficult to define their role in energy homeostasis accurately under normal feeding conditions. We show that knockdown of Sir2 in the larval fat body results in increased fat levels. Moreover, using genetic mosaics, we demonstrate that Sir2 restricts fat accumulation in individual cells of the fat body in a cell-autonomous manner. Consistent with this function, changes in the expression of metabolic enzymes in Sir2 mutants point to a shift away from catabolism. Surprisingly, although Sir2 is typically upregulated under conditions of starvation, Sir2 mutant larvae survive better than wild type under conditions of amino-acid starvation as long as sugars are provided. Our findings point to a Sir2-mediated pathway that activates a catabolic response to amino-acid starvation irrespective of the sugar content of the diet.

Lipid metabolism and body composition in Gclm(-/-) mice

Energy Technology Data Exchange (ETDEWEB)

Kendig, Eric L. [Department of Environmental Health, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Chen, Ying [Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Denver, Aurora, CO 80045 (United States); Krishan, Mansi; Johansson, Elisabet; Schneider, Scott N. [Department of Environmental Health, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Genter, Mary Beth; Nebert, Daniel W. [Department of Environmental Health, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Shertzer, Howard G., E-mail: shertzhg@ucmail.uc.edu [Department of Environmental Health, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States); Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056, Cincinnati, OH 45267 (United States)

2011-12-15

In humans and experimental animals, high fat diets (HFD) are associated with risk factors for metabolic diseases, such as excessive weight gain and adiposity, insulin resistance and fatty liver. Mice lacking the glutamate-cysteine ligase modifier subunit gene (Gclm(-/-)) and deficient in glutathione (GSH), are resistant to HFD-mediated weight gain. Herein, we evaluated Gclm-associated regulation of energy metabolism, oxidative stress, and glucose and lipid homeostasis. C57BL/6J Gclm(-/-) mice and littermate wild-type (WT) controls received a normal diet or an HFD for 11 weeks. HFD-fed Gclm(-/-) mice did not display a decreased respiratory quotient, suggesting that they are unable to process lipid for metabolism. Although dietary energy consumption and intestinal lipid absorption were unchanged in Gclm(-/-) mice, feeding these mice an HFD did not produce excess body weight nor fat storage. Gclm(-/-) mice displayed higher basal metabolic rates resulting from higher activities of liver mitochondrial NADH-CoQ oxidoreductase, thus elevating respiration. Although Gclm(-/-) mice exhibited strong systemic and hepatic oxidative stress responses, HFD did not promote glucose intolerance or insulin resistance. Furthermore, HFD-fed Gclm(-/-) mice did not develop fatty liver, likely resulting from very low expression levels of genes encoding lipid metabolizing enzymes. We conclude that Gclm is involved in the regulation of basal metabolic rate and the metabolism of dietary lipid. Although Gclm(-/-) mice display a strong oxidative stress response, they are protected from HFD-induced excessive weight gain and adipose deposition, insulin resistance and steatosis. -- Highlights: Black-Right-Pointing-Pointer A high fat diet does not produce body weight and fat gain in Gclm(-/-) mice. Black-Right-Pointing-Pointer A high fat diet does not induce steatosis or insulin resistance in Gclm(-/-) mice. Black-Right-Pointing-Pointer Gclm(-/-) mice have high basal metabolism and mitochondrial

Good, Bad, or Ugly: the Biological Roles of Bone Marrow Fat.

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Singh, Lakshman; Tyagi, Sonia; Myers, Damian; Duque, Gustavo

2018-04-01

Bone marrow fat expresses mixed characteristics, which could correspond to white, brown, and beige types of fat. Marrow fat could act as either energy storing and adipokine secreting white fat or as a source of energy for hematopoiesis and bone metabolism, thus acting as brown fat. However, there is also a negative interaction between marrow fat and other elements of the bone marrow milieu, which is known as lipotoxicity. In this review, we will describe the good and bad roles of marrow fat in the bone, while focusing on the specific components of the negative effect of marrow fat on bone metabolism. Lipotoxicity in the bone is exerted by bone marrow fat through the secretion of adipokines and free fatty acids (FFA) (predominantly palmitate). High levels of FFA found in the bone marrow of aged and osteoporotic bone are associated with decreased osteoblastogenesis and bone formation, decreased hematopoiesis, and increased osteoclastogenesis. In addition, FFA such as palmitate and stearate induce apoptosis and dysfunctional autophagy in the osteoblasts, thus affecting their differentiation and function. Regulation of marrow fat could become a therapeutic target for osteoporosis. Inhibition of the synthesis of FFA by marrow fat could facilitate osteoblastogenesis and bone formation while affecting osteoclastogenesis. However, further studies testing this hypothesis are still required.

Maternal obesity and high-fat diet program offspring metabolic syndrome.

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Desai, Mina; Jellyman, Juanita K; Han, Guang; Beall, Marie; Lane, Robert H; Ross, Michael G

2014-09-01

We determined the potential programming effects of maternal obesity and high-fat (HF) diet during pregnancy and/or lactation on offspring metabolic syndrome. A rat model of maternal obesity was created using an HF diet prior to and throughout pregnancy and lactation. At birth, pups were cross-fostered, thereby generating 4 paradigms of maternal diets during pregnancy/lactation: (1) control (Con) diet during pregnancy and lactation (Con/Con), (2) HF during pregnancy and lactation (HF/HF), (3) HF during pregnancy alone (HF/Con), and (4) HF during lactation alone (Con/HF). Maternal phenotype during pregnancy and the end of lactation evidenced markedly elevated body fat and plasma corticosterone levels in HF dams. In the offspring, the maternal HF diet during pregnancy alone programmed increased offspring adiposity, although with normal body weight, whereas the maternal HF diet during lactation increased both body weight and adiposity. Metabolic disturbances, particularly that of hyperglycemia, were apparent in all groups exposed to the maternal HF diet (during pregnancy and/or lactation), although differences were apparent in the manifestation of insulin resistant vs insulin-deficient phenotypes. Elevated systolic blood pressure was manifest in all groups, implying that exposure to an obese/HF environment is disadvantageous for offspring health, regardless of pregnancy or lactation periods. Nonetheless, the underlying mechanism may differ because offspring that experienced in utero HF exposure had increased corticosterone levels. Maternal obesity/HF diet has a marked impact on offspring body composition and the risk of metabolic syndrome was dependent on the period of exposure during pregnancy and/or lactation. Copyright © 2014 Mosby, Inc. All rights reserved.

THE ROLE OF GROWTH HORMONE IN LIPID METABOLISM

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I Gusti Ayu Dewi Ratnayanti

2013-04-01

Full Text Available Growth hormone (GH is one of the hormones that regulate metabolism, including lipid metabolism. GH can regulate the amount of fat in the tissue and also the level of lipid profile. Growth hormone affects the lipid in the tissue and blood by modulating the lipid metabolism, especially through the regulation of synthesis, excretion and breakdown of internal lipids. Research showed that GH could consistently lower the level of total cholesterol and LDL, whereas its effect on triglyceride and HDL level showed varying results. Growth hormone induces lypolisis by stimulating the activity of HSL and LPL and thereby influenced the triglyceride level and tissue fat storage. Cholesterol and lipoprotein levels are controlled by regulating the synthesis of cholesterol by lowering the activity of HMGCoA reductase. The excretion of cholesterol through the bile is also enhanced by stimulating the activity of enzymes C7?OH. The breakdown of VLDL and LDL are enhanced by increasing the expression of LDL receptor and ApoE as well as affecting the editing of mRNA ApoB100. Increase activity of LPL is also known to be the important factor in the HDL metabolism

Daily Stressors, Past Depression, and Metabolic Responses to High-Fat Meals: A Novel Path to Obesity

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Kiecolt-Glaser, Janice K.; Habash, Diane L.; Fagundes, Christopher P.; Andridge, Rebecca; Peng, Juan; Malarkey, William B.; Belury, Martha A.

2014-01-01

Background Depression and stress promote obesity. This study addressed the impact of daily stressors and a history of major depressive disorder (MDD) on obesity-related metabolic responses to high-fat meals. Methods This double-blind, randomized crossover study included serial assessments of resting energy expenditure (REE), fat and carbohydrate oxidation, triglycerides, cortisol, insulin and glucose before and after two high-fat meals. During two separate 9.5 hour admissions, 58 healthy women (38 breast cancer survivors and 20 demographically-similar controls), mean age 53.1 years, received either a high saturated fat meal or a high oleic sunflower oil meal. Prior day stressors were assessed by the Daily Inventory of Stressful Events and MDD history by the Structured Clinical Interview for DSM-IV. Results Greater numbers of stressors were associated with lower post-meal REE (P=.008), lower fat oxidation (P=.04), and higher insulin (P=.01), with nonsignificant effects for cortisol (P=.25) and glucose (P=.33). Women with prior MDD had higher cortisol (P=.008), and higher fat oxidation (P=.004), without significant effects for REE (P=.26), insulin (P=.25), and glucose (P=.38). Women with a depression history who also had more prior day stressors had a higher peak triglyceride response than other participants (P=.01). The only difference between meals was higher postprandial glucose following sunflower oil compared to saturated fat (P=.03). Conclusions The cumulative 6-hour difference between one prior day stressor and no stressors translates into 104 kcal, a difference that could add almost 11 pounds/year. These findings illustrate how stress and depression alter metabolic responses to high-fat meals in ways that promote obesity. PMID:25034950

Metabolic rate regulates L1 longevity in C. elegans.

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Inhwan Lee

Full Text Available Animals have to cope with starvation. The molecular mechanisms by which animals survive long-term starvation, however, are not clearly understood. When they hatch without food, C. elegans arrests development at the first larval stage (L1 and survives more than two weeks. Here we show that the survival span of arrested L1s, which we call L1 longevity, is a starvation response regulated by metabolic rate during starvation. A high rate of metabolism shortens the L1 survival span, whereas a low rate of metabolism lengthens it. The longer worms are starved, the slower they grow once they are fed, suggesting that L1 arrest has metabolic costs. Furthermore, mutants of genes that regulate metabolism show altered L1 longevity. Among them, we found that AMP-dependent protein kinase (AMPK, as a key energy sensor, regulates L1 longevity by regulating this metabolic arrest. Our results suggest that L1 longevity is determined by metabolic rate and that AMPK as a master regulator of metabolism controls this arrest so that the animals survive long-term starvation.

Transcriptome Analyses Reveal Lipid Metabolic Process in Liver Related to the Difference of Carcass Fat Content in Rainbow Trout (Oncorhynchus mykiss

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Guo Hu

2016-01-01

Full Text Available Excessive accumulation of carcass fat in farm animals, including fish, has a significant impact on meat quality and on the cost of feeding. Similar to farmed animals and humans, the liver can be considered one of the most important organs involved in lipid metabolism in rainbow trout (Oncorhynchus mykiss. RNA-seq based whole transcriptome sequencing was performed to liver tissue of rainbow trout with high and low carcass fat content in this study. In total 1,694 differentially expressed transcripts were identified, including many genes involved in lipid metabolism, such as L-FABP, adiponectin, PPAR-α, PPAR-β, and IGFBP1a. Evidence presented in this study indicated that lipid metabolic process in liver may be related to the difference of carcass fat content. The relevance of PPAR-α and PPAR-β as molecular markers for fat storage in liver should be worthy of further investigation.

A High-Fat Diet Causes Impairment in Hippocampal Memory and Sex-Dependent Alterations in Peripheral Metabolism

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Erica L. Underwood

2016-01-01

Full Text Available While high-fat diets are associated with rising incidence of obesity/type-2 diabetes and can induce metabolic and cognitive deficits, sex-dependent comparisons are rarely systematically made. Effects of exclusive consumption of a high-fat diet (HFD on systemic metabolism and on behavioral measures of hippocampal-dependent memory were compared in young male and female LE rats. Littermates were fed from weaning either a HFD or a control diet (CD for 12 wk prior to testing. Sex-different effects of the HFD were observed in classic metabolic signs associated with type-2 diabetes. Males fed the HFD became obese, and had elevated fasted blood glucose levels, elevated corticosterone, and impaired glucose-tolerance, while females on the HFD exhibited only elevated corticosterone. Regardless of peripheral metabolism alteration, rats of both sexes fed the HFD were equally impaired in a spatial object recognition memory task associated with impaired hippocampal function. While the metabolic changes reported here have been characterized previously in males, the set of diet-induced effects observed here in females are novel. Impaired memory can have significant cognitive consequences, over the short-term and over the lifespan. A significant need exists for comparative research into sex-dependent differences underlying obesity and metabolic syndromes relating systemic, cognitive, and neural plasticity mechanisms.

Metabolic regulation of yeast

Science.gov (United States)

Fiechter, A.

1982-12-01

Metabolic regulation which is based on endogeneous and exogeneous process variables which may act constantly or time dependently on the living cell is discussed. The observed phenomena of the regulation are the result of physical, chemical, and biological parameters. These parameters are identified. Ethanol is accumulated as an intermediate product and the synthesis of biomass is reduced. This regulatory effect of glucose is used for the aerobic production of ethanol. Very high production rates are thereby obtained. Understanding of the regulation mechanism of the glucose effect has improved. In addition to catabolite repression, several other mechanisms of enzyme regulation have been described, that are mostly governed by exogeneous factors. Glucose also affects the control of respiration in a third class of yeasts which are unable to make use of ethanol as a substrate for growth. This is due to the lack of any anaplerotic activity. As a consequence, diauxic growth behavior is reduced to a one-stage growth with a drastically reduced cell yield. The pulse chemostat technique, a systematic approach for medium design is developed and medium supplements that are essential for metabolic control are identified.

CNS β3-adrenergic receptor activation regulates feeding behavior, white fat browning, and body weight.

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Richard, Jennifer E; López-Ferreras, Lorena; Chanclón, Belén; Eerola, Kim; Micallef, Peter; Skibicka, Karolina P; Wernstedt Asterholm, Ingrid

2017-09-01

Pharmacological β 3 -adrenergic receptor (β 3 AR) activation leads to increased mitochondrial biogenesis and activity in white adipose tissue (WAT), a process commonly referred to as "browning", and transiently increased insulin release. These effects are associated with improved metabolic function and weight loss. It is assumed that this impact of β 3 AR agonists is mediated solely through activation of β 3 ARs in adipose tissue. However, β 3 ARs are also found in the brain, in areas such as the brain stem and the hypothalamus, which provide multisynaptic innervation to brown and white adipose depots. Thus, contrary to the current adipocentric view, the central nervous system (CNS) may also have the ability to regulate energy balance and metabolism through actions on central β 3 ARs. Therefore, this study aimed to elucidate whether CNS β 3 ARs can regulate browning of WAT and other aspects of metabolic regulation, such as food intake control and insulin release. We found that acute central injection of β 3 AR agonist potently reduced food intake, body weight, and increased hypothalamic neuronal activity in rats. Acute central β 3 AR stimulation was also accompanied by a transient increase in circulating insulin levels. Moreover, subchronic central β 3 AR agonist treatment led to a browning response in both inguinal (IWAT) and gonadal WAT (GWAT), along with reduced GWAT and increased BAT mass. In high-fat, high-sugar-fed rats, subchronic central β 3 AR stimulation reduced body weight, chow, lard, and sucrose water intake, in addition to increasing browning of IWAT and GWAT. Collectively, our results identify the brain as a new site of action for the anorexic and browning impact of β 3 AR activation. Copyright © 2017 the American Physiological Society.

Quantification of hepatic and visceral fat by CT and MR imaging: relevance to the obesity epidemic, metabolic syndrome and NAFLD.

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Graffy, Peter M; Pickhardt, Perry J

2016-06-01

Trends in obesity have continued to increase in the developed world over the past few decades, along with related conditions such as metabolic syndrome, which is strongly associated with this epidemic. Novel and innovative methods to assess relevant obesity-related biomarkers are needed to determine the clinical significance, allow for surveillance and intervene if appropriate. Aggregations of specific types of fat, specifically hepatic and visceral adiposity, are now known to be correlated with these conditions, and there are a variety of imaging techniques to identify and quantify their distributions and provide diagnostic information. These methods are particularly salient for metabolic syndrome, which is related to both hepatic and visceral adiposity but currently not defined by it. Simpler non-specific fat measurements, such as body weight, abdominal circumference and body mass index are more frequently used but lack the ability to characterize fat location. In addition, non-alcoholic fatty liver disease (NAFLD) is a related condition that carries relevance not only for obesity-related diseases but also for the progression of the liver-specific disease, including non-alcoholic steatohepatitis and cirrhosis, albeit at a much lower frequency. Recent CT and MRI techniques have emerged to potentially optimize diagnosing metabolic syndrome and NAFLD through non-invasive quantification of visceral fat and hepatic steatosis with high accuracy. These imaging modalities should aid us in further understanding the relationship of hepatic and visceral fat to the obesity-related conditions such as metabolic syndrome, NAFLD and cardiovascular disease.

Overfeeding, autonomic regulation and metabolic consequences.

NARCIS (Netherlands)

Scheurink, A.J.W.; Balkan, B; Strubbe, J.H.; van Dijk, G.; Steffens, A.B

The autonomic nervous system plays an important role in the regulation of body processes in health and disease. Overfeeding and obesity (a disproportional increase of the fat mass of the body) are often accompanied by alterations in both sympathetic and parasympathetic autonomic functions. The

Hyperthyroidism increases brown fat metabolism in humans.

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Lahesmaa, Minna; Orava, Janne; Schalin-Jäntti, Camilla; Soinio, Minna; Hannukainen, Jarna C; Noponen, Tommi; Kirjavainen, Anna; Iida, Hidehiro; Kudomi, Nobuyuki; Enerbäck, Sven; Virtanen, Kirsi A; Nuutila, Pirjo

2014-01-01

Thyroid hormones are important regulators of brown adipose tissue (BAT) development and function. In rodents, BAT metabolism is up-regulated by thyroid hormones. The purpose of this article was to investigate the impact of hyperthyroidism on BAT metabolism in humans. This was a follow-up study using positron emission tomography imaging. Glucose uptake (GU) and perfusion of BAT, white adipose tissue, skeletal muscle, and thyroid gland were measured using [18F]2-fluoro-2-deoxy-D-glucose and [15O]H2O and positron emission tomography in 10 patients with overt hyperthyroidism and in 8 healthy participants. Five of the hyperthyroid patients were restudied after restoration of euthyroidism. Supraclavicular BAT was quantified with magnetic resonance imaging or computed tomography and energy expenditure (EE) with indirect calorimetry. Compared with healthy participants, hyperthyroid participants had 3-fold higher BAT GU (2.7±2.3 vs 0.9±0.1 μmol/100 g/min, P=.0013), 90% higher skeletal muscle GU (Phyperthyroidism, serum free T4 and free T3 were strongly associated with EE and lipid oxidation rates (Pmetabolism (PHyperthyroidism had no effect on BAT perfusion, whereas it stimulated skeletal muscle perfusion (P=.04). Thyroid gland GU did not differ between hyperthyroid and euthyroid study subjects. Hyperthyroidism increases GU in BAT independently of BAT perfusion. Hyperthyroid patients are characterized by increased skeletal muscle metabolism and lipid oxidation rates.

Milk fat globules: fatty acid composition, size and in vivo regulation of fat liquidity.

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Timmen, H; Patton, S

1988-07-01

Populations of large and small milk fat globules were isolated and analyzed to determine differences in fatty acid composition. Globule samples were obtained by centrifugation from milks of a herd and of individual animals produced under both pasture and barn feeding. Triacylglycerols of total globule lipids were prepared by thin layer chromatography and analyzed for fatty acid composition by gas chromatography. Using content of the acids in large globules as 100%, small globules contained fewer short-chain acids, -5.9%, less stearic acid, -22.7%, and more oleic acids, +4.6%, mean values for five trials. These differences are consistent with alternative use of short-chain acids or oleic acid converted from stearic acid to maintain liquidity at body temperature of milk fat globules and their precursors, intracellular lipid droplets. Stearyl-CoA desaturase (EC 1.14.99.5), which maintains fluidity of cellular endoplasmic reticulum membrane, is suggested to play a key role in regulating globule fat liquidity. Possible origins of differences between individual globules in fatty acid composition of their triacylglycerols are discussed.

Metabolic syndrome: Differences for Asian Americans is in their percentage of body fat

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Patricia Alpert

2016-09-01

Full Text Available Asian Americans are not frequently thought of as being obese or overweight yet some of the Asian American subgroups have a disproportionate risk for cardiovascular disease and type 2 diabetes mellitus. Although the standardized body mass index (BMI assessment is an adequate tool for reporting secular prevalence trends for overweight/obesity across populations, it falls short in accuracy when assessing Asian Americans. In recent years more has been written about the re-evaluation of BMI cut points for normal weight, overweight, or obese Asian Americans. Additionally, the waist circumference norm was modified to indicate a smaller waist size is a risk for metabolic syndrome. The purpose of this paper is to provide an overview of the research literature on BMI and percentage of body fat as it relates to health risk for metabolic syndrome for Asian American subgroups. Three databases were used to identify articles for this review: Google Scholar, CINHAL, and PubMed. Seven hundred twenty-six articles were initially identified as meeting the criteria; 690 articles were eliminated after a review of the article titles revealed the content did not meet the focus of this review. Of the remaining articles, 19 were eliminated after a review of the abstracts indicated they were meta-analyses, review articles, or case studies. The remaining 18 articles were included in this review. Three common themes emerged. (1 The differences in BMI and body fat percentage are evident between Asian Americans and other ethnic groups. (2 Differences in the percentage of body fat exist between Asian American subgroups, and between Asian Americans and Asian immigrants. (3 There are differences in disease development end points when comparing Asian American subgroups and Asian immigrant subgroups. There are differences in body fat distribution and body fat percentages as well as BMI compared to other ethnic groups for metabolic syndrome. There are also differences between Asian

High-fat diet feeding alters metabolic response to fasting/non fasting conditions. Effect on caveolin expression and insulin signalling.

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Gómez-Ruiz, Ana; Milagro, Fermín I; Campión, Javier; Martínez, J Alfredo; de Miguel, Carlos

2011-04-13

The effect of food intake on caveolin expression in relation to insulin signalling was studied in skeletal muscle and adipocytes from retroperitoneal (RP) and subcutaneous (SC) adipose tissue, comparing fasted (F) to not fasted (NF) rats that had been fed a control or high-fat (HF) diet for 72 days. Serum glucose was analysed enzymatically and insulin and leptin by ELISA. Caveolins and insulin signalling intermediaries (IR, IRS-1 and 2 and GLUT4) were determined by RT-PCR and western blotting. Caveolin and IR phosphorylation was measured by immunoprecipitation. Data were analysed with Mann-Whitney U test. High-fat fed animals showed metabolic alterations and developed obesity and insulin resistance. In skeletal muscle, food intake (NF) induced activation of IR and increased expression of IRS-2 in control animals with normal metabolic response. HF animals became overweight, hyperglycaemic, hyperinsulinemic, hyperleptinemic and showed insulin resistance. In skeletal muscle of these animals, food intake (NF) also induced IRS-2 expression together with IR, although this was not active. Caveolin 3 expression in this tissue was increased by food intake (NF) in animals fed either diet. In RP adipocytes of control animals, food intake (NF) decreased IR and IRS-2 expression but increased that of GLUT4. A similar but less intense response was found in SC adipocytes. Food intake (NF) did not change caveolin expression in RP adipocytes with either diet, but in SC adipocytes of HF animals a reduction was observed. Food intake (NF) decreased caveolin-1 phosphorylation in RP but increased it in SC adipocytes of control animals, whereas it increased caveolin-2 phosphorylation in both types of adipocytes independently of the diet. Animals fed a control-diet show a normal response to food intake (NF), with activation of the insulin signalling pathway but without appreciable changes in caveolin expression, except a small increase of caveolin-3 in muscle. Animals fed a high-fat diet

Aqueous Extract of Black Maca Prevents Metabolism Disorder via Regulating the Glycolysis/Gluconeogenesis-TCA Cycle and PPARα Signaling Activation in Golden Hamsters Fed a High-Fat, High-Fructose Diet.

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Wan, Wenting; Li, Hongxiang; Xiang, Jiamei; Yi, Fan; Xu, Lijia; Jiang, Baoping; Xiao, Peigen

2018-01-01

Maca ( Lepidium meyenii Walpers) has been used as a dietary supplement and ethnomedicine for centuries. Recently, maca has become a high profile functional food worldwide because of its multiple biological activities. This study is the first explorative research to investigate the prevention and amelioration capacity of the aqueous extract of black maca (AEM) on high-fat, high-fructose diet (HFD)-induced metabolism disorder in golden hamsters and to identify the potential mechanisms involved in these effects. For 20 weeks, 6-week-old male golden hamsters were fed the following respective diets: (1) a standard diet, (2) HFD, (3) HFD supplemented with metformin, or (4) HFD supplemented with three doses of AEM (300, 600, or 1,200 mg/kg). After 20 weeks, the golden hamsters that received daily AEM supplementation presented with the beneficial effects of improved hyperlipidemia, hyperinsulinemia, insulin resistance, and hepatic steatosis in vivo . Based on the hepatic metabolomic analysis results, alterations in metabolites associated with pathological changes were examined. A total of 194 identified metabolites were mapped to 46 relative metabolic pathways, including those of energy metabolism. In addition, via in silico profiling for secondary maca metabolites by a joint pharmacophore- and structure-based approach, a compound-target-disease network was established. The results revealed that 32 bioactive compounds in maca targeted 16 proteins involved in metabolism disorder. Considering the combined metabolomics and virtual screening results, we employed quantitative real-time PCR assays to verify the gene expression of key enzymes in the relevant pathways. AEM promoted glycolysis and inhibited gluconeogenesis via regulating the expression of key genes such as Gck and Pfkm . Moreover, AEM upregulated tricarboxylic acid (TCA) cycle flux by changing the concentrations of intermediates and increasing the mRNA levels of Aco2 , Fh , and Mdh2 . In addition, the lipid

Aqueous Extract of Black Maca Prevents Metabolism Disorder via Regulating the Glycolysis/Gluconeogenesis-TCA Cycle and PPARα Signaling Activation in Golden Hamsters Fed a High-Fat, High-Fructose Diet

Directory of Open Access Journals (Sweden)

Wenting Wan

2018-04-01

Full Text Available Maca (Lepidium meyenii Walpers has been used as a dietary supplement and ethnomedicine for centuries. Recently, maca has become a high profile functional food worldwide because of its multiple biological activities. This study is the first explorative research to investigate the prevention and amelioration capacity of the aqueous extract of black maca (AEM on high-fat, high-fructose diet (HFD-induced metabolism disorder in golden hamsters and to identify the potential mechanisms involved in these effects. For 20 weeks, 6-week-old male golden hamsters were fed the following respective diets: (1 a standard diet, (2 HFD, (3 HFD supplemented with metformin, or (4 HFD supplemented with three doses of AEM (300, 600, or 1,200 mg/kg. After 20 weeks, the golden hamsters that received daily AEM supplementation presented with the beneficial effects of improved hyperlipidemia, hyperinsulinemia, insulin resistance, and hepatic steatosis in vivo. Based on the hepatic metabolomic analysis results, alterations in metabolites associated with pathological changes were examined. A total of 194 identified metabolites were mapped to 46 relative metabolic pathways, including those of energy metabolism. In addition, via in silico profiling for secondary maca metabolites by a joint pharmacophore- and structure-based approach, a compound-target-disease network was established. The results revealed that 32 bioactive compounds in maca targeted 16 proteins involved in metabolism disorder. Considering the combined metabolomics and virtual screening results, we employed quantitative real-time PCR assays to verify the gene expression of key enzymes in the relevant pathways. AEM promoted glycolysis and inhibited gluconeogenesis via regulating the expression of key genes such as Gck and Pfkm. Moreover, AEM upregulated tricarboxylic acid (TCA cycle flux by changing the concentrations of intermediates and increasing the mRNA levels of Aco2, Fh, and Mdh2. In addition, the lipid

High fat diet-induced non alcoholic fatty liver disease in rats is associated with hyperhomocysteinemia caused by down regulation of the transsulphuration pathway

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Napolitano Mariarosaria

2011-04-01

Full Text Available Abstract Background Hyperhomocysteinemia (HHcy causes increased oxidative stress and is an independent risk factor for cardiovascular disease. Oxidative stress is now believed to be a major contributory factor in the development of non alcoholic fatty liver disease, the most common liver disorder worldwide. In this study, the changes which occur in homocysteine (Hcy metabolism in high fat-diet induced non alcoholic fatty liver disease (NAFLD in rats were investigated. Methods and results After feeding rats a standard low fat diet (control or a high fat diet (57% metabolisable energy as fat for 18 weeks, the concentration of homocysteine in the plasma was significantly raised while that of cysteine was lowered in the high fat as compared to the control diet fed animals. The hepatic activities of cystathionine β-synthase (CBS and cystathionine γ-lyase (CGS, the enzymes responsible for the breakdown of homocysteine to cysteine via the transsulphuration pathway in the liver, were also significantly reduced in the high fat-fed group. Conclusions These results indicate that high fat diet-induced NAFLD in rats is associated with increased plasma Hcy levels caused by down-regulation of hepatic CBS and CGL activity. Thus, HHcy occurs at an early stage in high fat diet-induced NAFLD and is likely to contribute to the increased risk of cardiovascular disease associated with the condition.

Bio F1B hamster: a unique animal model with reduced lipoprotein lipase activity to investigate nutrient mediated regulation of lipoprotein metabolism

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Cornish Marion L

2007-12-01

Full Text Available Abstract Background Bio F1B hamster is an inbred hybrid strain that is highly susceptible to diet-induced atherosclerosis. We previously reported that feeding a high fat fish oil diet to Bio F1B hamster caused severe hyperlipidaemia. In this study we compared the effects of various diets in the Bio F1B hamster and the Golden Syrian hamster, which is an outbred hamster strain to investigate whether genetic background plays an important role in dietary fat mediated regulation of lipoprotein metabolism. We further investigated the mechanisms behind diet-induced hyperlipidaemia in F1B hamster. Methods The Bio F1B and Golden Syrian hamsters, 8 weeks old, were fed high fat diets rich in either monounsaturated fatty acids, an n-6: n-3 ratio of 5 or a fish oil diet for 4 weeks. Animals were fasted overnight and blood and tissue samples were collected. Plasma was fractionated into various lipoprotein fractions and assayed for triacylglycerol and cholesterol concentrations. Plasma lipoprotein lipase activity was measured using radioisotope method. Microsomal triglyceride transfer protein activity was measured in the liver and intestine. Plasma apolipoproteinB48, -B100 and apolipoprotein E was measured using Western blots. Two-way ANOVA was used to determine the effect of diet type and animal strain. Results The fish oil fed F1B hamsters showed milky plasma after a 14-hour fast. Fish oil feeding caused accumulation of apolipoproteinB48 containing lipoprotein particles suggesting hindrance of triglyceride-rich lipoprotein clearance. There was no significant effect of diet or strain on hepatic or intestinal microsomal triglyceride transfer protein activity indicating that hyperlipidaemia is not due to an increase in the assembly or secretion of lipoprotein particles. F1B hamsters showed significantly reduced levels of lipoprotein lipase activity, which was inhibited by fish oil feeding. Conclusion Evidence is presented for the first time that alterations in

Cold-Inducible SIRT6 Regulates Thermogenesis of Brown and Beige Fat

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Lu Yao

2017-07-01

Full Text Available Promoting development and function of brown and beige fat may reduce obesity. Here, we show that fat SIRT6 expression is markedly induced by cold exposure and a β-adrenergic agonist. Deletion of SIRT6 in adipose tissue impairs the thermogenic function of brown adipocytes, causing a morphological “whitening” of brown fat, reduced oxygen (O2 consumption, obesity, decreased core body temperature, and cold sensitivity. Fat SIRT6-deleted mice exhibit increased blood glucose levels, severe insulin resistance, and hepatic steatosis. Moreover, SIRT6 deficiency inhibits the browning of white adipose tissue (WAT following cold exposure or β3-agonist treatment. Depletion of SIRT6 expression in brown adipocytes reduces expression of thermogenic genes, causing a reduction in cellular respiration. Conversely, SIRT6 overexpression in primary fat cells stimulates the thermogenic program. Mechanistically, SIRT6 interacts with and promotes phospho-ATF2 binding to the PGC-1α gene promoter to activate its expression. The present study reveals a critical role for SIRT6 in regulating thermogenesis of fat.

Effects of resveratrol on gut microbiota and fat storage in a mouse model with high-fat-induced obesity.

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Qiao, Yi; Sun, Jin; Xia, Shufang; Tang, Xue; Shi, Yonghui; Le, Guowei

2014-06-01

Recent studies have investigated the anti-obesity effect of resveratrol, but the pathways through which resveratrol resists obesity are not clear. In the present study, we hypothesize that resveratrol exerts anti-obesity effects that are likely mediated by mechanisms of regulating gut microbes, and in turn, improving fat storage and metabolism. Gut microbes, glucose and lipid metabolism in high-fat diet (HF) mice in vivo are investigated after resveratrol treatment. Several biochemical markers are measured. Fluorescence in situ hybridization and flow cytometry are used to monitor and quantify the changes in gut microbiota. The key genes related to fat storage and metabolism in the liver and visceral adipose tissues are measured by real-time PCR. The results show that resveratrol (200 mg per kg per day) significantly lowers both body and visceral adipose weights, and reduces blood glucose and lipid levels in HF mice. Resveratrol improves the gut microbiota dysbiosis induced by the HF diet, including increasing the Bacteroidetes-to-Firmicutes ratios, significantly inhibiting the growth of Enterococcus faecalis, and increasing the growth of Lactobacillus and Bifidobacterium. Furthermore, resveratrol significantly increases the fasting-induced adipose factor (Fiaf, a key gene negatively regulated by intestinal microbes) expression in the intestine. Resveratrol significantly decreases mRNA expression of Lpl, Scd1, Ppar-γ, Acc1, and Fas related to fatty acids synthesis, adipogenesis and lipogenesis, which may be driven by increased Fiaf expression. The Pearson's correlation coefficient shows that there is a negative correlation between the body weight and the ratios of Bacteroidetes-to-Firmicutes. Therefore, resveratrol mediates the composition of gut microbes, and in turn, through the Fiaf signaling pathway, accelerates the development of obesity.

Obesity, Fat Mass and Immune System: Role for Leptin

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Vera Francisco

2018-06-01

Full Text Available Obesity is an epidemic disease characterized by chronic low-grade inflammation associated with a dysfunctional fat mass. Adipose tissue is now considered an extremely active endocrine organ that secretes cytokine-like hormones, called adipokines, either pro- or anti-inflammatory factors bridging metabolism to the immune system. Leptin is historically one of most relevant adipokines, with important physiological roles in the central control of energy metabolism and in the regulation of metabolism-immune system interplay, being a cornerstone of the emerging field of immunometabolism. Indeed, leptin receptor is expressed throughout the immune system and leptin has been shown to regulate both innate and adaptive immune responses. This review discusses the latest data regarding the role of leptin as a mediator of immune system and metabolism, with particular emphasis on its effects on obesity-associated metabolic disorders and autoimmune and/or inflammatory rheumatic diseases.

AMP-Activated Protein Kinase (AMPK) Regulates Energy Metabolism through Modulating Thermogenesis in Adipose Tissue

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Wu, Lingyan; Zhang, Lina; Li, Bohan; Jiang, Haowen; Duan, Yanan; Xie, Zhifu; Shuai, Lin; Li, Jia; Li, Jingya

2018-01-01

Obesity occurs when excess energy accumulates in white adipose tissue (WAT), whereas brown adipose tissue (BAT), which is specialized in dissipating energy through thermogenesis, potently counteracts obesity. White adipocytes can be converted to thermogenic “brown-like” cells (beige cells; WAT browning) under various stimuli, such as cold exposure. AMP-activated protein kinase (AMPK) is a crucial energy sensor that regulates energy metabolism in multiple tissues. However, the role of AMPK in adipose tissue function, especially in the WAT browning process, is not fully understood. To illuminate the effect of adipocyte AMPK on energy metabolism, we generated Adiponectin-Cre-driven adipose tissue-specific AMPK α1/α2 KO mice (AKO). These AKO mice were cold intolerant and their inguinal WAT displayed impaired mitochondrial integrity and biogenesis, and reduced expression of thermogenic markers upon cold exposure. High-fat-diet (HFD)-fed AKO mice exhibited increased adiposity and exacerbated hepatic steatosis and fibrosis and impaired glucose tolerance and insulin sensitivity. Meanwhile, energy expenditure and oxygen consumption were markedly decreased in the AKO mice both in basal conditions and after stimulation with a β3-adrenergic receptor agonist, CL 316,243. In contrast, we found that in HFD-fed obese mouse model, chronic AMPK activation by A-769662 protected against obesity and related metabolic dysfunction. A-769662 alleviated HFD-induced glucose intolerance and reduced body weight gain and WAT expansion. Notably, A-769662 increased energy expenditure and cold tolerance in HFD-fed mice. A-769662 treatment also induced the browning process in the inguinal fat depot of HFD-fed mice. Likewise, A-769662 enhanced thermogenesis in differentiated inguinal stromal vascular fraction (SVF) cells via AMPK signaling pathway. In summary, a lack of adipocyte AMPKα induced thermogenic impairment and obesity in response to cold and nutrient-overload, respectively

ApoB100-LDL acts as a metabolic signal from liver to peripheral fat causing inhibition of lipolysis in adipocytes.

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Josefin Skogsberg

Full Text Available BACKGROUND: Free fatty acids released from adipose tissue affect the synthesis of apolipoprotein B-containing lipoproteins and glucose metabolism in the liver. Whether there also exists a reciprocal metabolic arm affecting energy metabolism in white adipose tissue is unknown. METHODS AND FINDINGS: We investigated the effects of apoB-containing lipoproteins on catecholamine-induced lipolysis in adipocytes from subcutaneous fat cells of obese but otherwise healthy men, fat pads from mice with plasma lipoproteins containing high or intermediate levels of apoB100 or no apoB100, primary cultured adipocytes, and 3T3-L1 cells. In subcutaneous fat cells, the rate of lipolysis was inversely related to plasma apoB levels. In human primary adipocytes, LDL inhibited lipolysis in a concentration-dependent fashion. In contrast, VLDL had no effect. Lipolysis was increased in fat pads from mice lacking plasma apoB100, reduced in apoB100-only mice, and intermediate in wild-type mice. Mice lacking apoB100 also had higher oxygen consumption and lipid oxidation. In 3T3-L1 cells, apoB100-containing lipoproteins inhibited lipolysis in a dose-dependent fashion, but lipoproteins containing apoB48 had no effect. ApoB100-LDL mediated inhibition of lipolysis was abolished in fat pads of mice deficient in the LDL receptor (Ldlr(-/-Apob(100/100. CONCLUSIONS: Our results show that the binding of apoB100-LDL to adipocytes via the LDL receptor inhibits intracellular noradrenaline-induced lipolysis in adipocytes. Thus, apoB100-LDL is a novel signaling molecule from the liver to peripheral fat deposits that may be an important link between atherogenic dyslipidemias and facets of the metabolic syndrome.

Aged interleukin-10tm1Cgn chronically inflamed mice have substantially reduced fat mass, metabolic rate, and adipokines.

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Reyhan M Westbrook

Full Text Available Interleukin 10tm1Cgn (IL 10tm mice have been utilized as a model of chronic inflammation and declining health span because of their propensity to develop chronic activation in NFkB pathways, skeletal muscle and cardiac changes, and mitochondrial dysfunction. We hypothesized that older IL 10tm frail mice would have alterations similar to frail, older humans in measured parameters of glucose metabolism, oxygen consumption (VO2, respiratory quotient (RQ, spontaneous locomotor activity, body composition and plasma adipokine levels. To test this hypothesis, we investigated these metabolic parameters in cohorts of 3, 10, and 20 month old IL 10tm female mice and age and gender matched C57Bl/6 mice. Insulin sensitivity, glucose homeostasis, locomotor activity and RQ were not significantly altered between the two strains of mice. Interestingly, old IL 10tm mice had significantly decreased VO2 when normalized by lean mass, but not when normalized by fat mass or the lean/fat mass ratio. NMR based body composition analysis and dissection weights show that fat mass is decreased with age in IL 10tm mice compared to controls. Further, plasma adiponectin and leptin were also decreased in IL 10tm.These findings suggest that frailty observed in this mouse model of chronic inflammation may in part be driven by alterations in fat mass, hormone secretion and energy metabolism.

Obesity, the metabolic syndrome, and type 2 diabetes in developing countries: role of dietary fats and oils.

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Misra, Anoop; Singhal, Neha; Khurana, Lokesh

2010-06-01

Developing countries are undergoing rapid nutrition transition concurrent with increases in obesity, the metabolic syndrome, and type 2 diabetes mellitus (T2DM). From a healthy traditional high-fiber, low-fat, low-calorie diet, a shift is occurring toward increasing consumption of calorie-dense foods containing refined carbohydrates, fats, red meats, and low fiber. Data show an increase in the supply of animal fats and increased intake of saturated fatty acid (SFAs) (obtained from coconut oil, palm oil, and ghee [clarified butter]) in many developing countries, particularly in South Asia and South-East Asia. In some South Asian populations, particularly among vegetarians, intake of n-3 polyunsaturated fatty acids (PUFAs) (obtained from flaxseed, mustard, and canola oils) and long-chain (LC) n-3 PUFAs (obtained from fish and fish oils) is low. Further, the effect of supplementation of n-3 PUFAs on metabolic risk factors and insulin resistance, except for demonstrated benefit in terms of decreased triglycerides, needs further investigation among South Asians. Data also show that intake of monounsaturated fatty acids (MUFAs) ranged from 4.7% to 16.4%en in developing countries, and supplementing it from olive, canola, mustard, groundnut, and rice bran oils may reduce metabolic risk. In addition, in some developing countries, intake of n-6 PUFAs (obtained from sunflower, safflower, corn, soybean, and sesame oils) and trans-fatty acids (TFAs) is increasing. These data show imbalanced consumption of fats and oils in developing countries, which may have potentially deleterious metabolic and glycemic consequences, although more research is needed. In view of the rapid rise of T2DM in developing countries, more aggressive public health awareness programs coupled with governmental action and clear country-specific guidelines are required, so as to promote widespread use of healthy oils, thus curbing intake of SFAs and TFAs, and increasing intake of n-3 PUFAs and MUFAs. Such

Subcutaneous to visceral fat ratio: a possible risk factor for metabolic syndrome and cardiovascular diseases

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Shafqat MN

2018-04-01

Full Text Available Muhammad Nabeel Shafqat,1 Miqdad Haider,2 1Department of Medicine, University of Medical Sciences “Serafin Ruiz de Zarate” Villa Clara (UCMVC, Villa Clara, Cuba; 2Department of Internal Medicine, Fatima Memorial Hospital, Fatima Memorial College of Medicine and Dentistry, Lahore, PakistanWe would like to comment, with great interest, about the recently published article “Visceral-to-subcutaneous fat ratio as a predictor of the multiple metabolic risk factors for subjects with normal waist circumference in Korea” by Oh et al,1 which we found very interesting and valuable. This study is a good step to determine the predictive value of visceral-to-subcutaneous fat ratio (VSR in persons with normal waist circumference for the diagnosis of risk factors for metabolic syndrome.View the original paper by Oh and colleagues.

Lipid metabolism and body composition in Gclm(−/−) mice

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Kendig, Eric L.; Chen, Ying; Krishan, Mansi; Johansson, Elisabet; Schneider, Scott N.; Genter, Mary Beth; Nebert, Daniel W.; Shertzer, Howard G.

2011-01-01

In humans and experimental animals, high fat diets (HFD) are associated with risk factors for metabolic diseases, such as excessive weight gain and adiposity, insulin resistance and fatty liver. Mice lacking the glutamate–cysteine ligase modifier subunit gene (Gclm(−/−)) and deficient in glutathione (GSH), are resistant to HFD-mediated weight gain. Herein, we evaluated Gclm-associated regulation of energy metabolism, oxidative stress, and glucose and lipid homeostasis. C57BL/6J Gclm(−/−) mice and littermate wild-type (WT) controls received a normal diet or an HFD for 11 weeks. HFD-fed Gclm(−/−) mice did not display a decreased respiratory quotient, suggesting that they are unable to process lipid for metabolism. Although dietary energy consumption and intestinal lipid absorption were unchanged in Gclm(−/−) mice, feeding these mice an HFD did not produce excess body weight nor fat storage. Gclm(−/−) mice displayed higher basal metabolic rates resulting from higher activities of liver mitochondrial NADH-CoQ oxidoreductase, thus elevating respiration. Although Gclm(−/−) mice exhibited strong systemic and hepatic oxidative stress responses, HFD did not promote glucose intolerance or insulin resistance. Furthermore, HFD-fed Gclm(−/−) mice did not develop fatty liver, likely resulting from very low expression levels of genes encoding lipid metabolizing enzymes. We conclude that Gclm is involved in the regulation of basal metabolic rate and the metabolism of dietary lipid. Although Gclm(−/−) mice display a strong oxidative stress response, they are protected from HFD-induced excessive weight gain and adipose deposition, insulin resistance and steatosis. -- Highlights: ► A high fat diet does not produce body weight and fat gain in Gclm(−/−) mice. ► A high fat diet does not induce steatosis or insulin resistance in Gclm(−/−) mice. ► Gclm(−/−) mice have high basal metabolism and mitochondrial oxygen consumption. �

Body fat distribution, metabolic and inflammatory markers and retinal microvasculature in school-age children. The Generation R Study.

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Gishti, O; Jaddoe, V W V; Hofman, A; Wong, T Y; Ikram, M K; Gaillard, R

2015-10-01

To examine the associations of body fatness, metabolic and inflammatory markers with retinal vessel calibers among children. We performed a population-based cohort study among 4145 school-age children. At the median age of 6.0 years (95% range 5.8, 8.0 years), we measured body mass index, total and abdominal fat mass, metabolic and inflammatory markers (blood levels of lipids, insulin and C-peptide and C-reactive protein) and retinal vascular calibers from retinal photographs. We observed that compared with normal weight children, obese children had narrower retinal arteriolar caliber (difference -0.21 s.d. score (SDS; 95% confidence interval (CI) -0.35, -0.06)), but not venular caliber. Continuous analyses showed that higher body mass index and total body fat mass, but not android/gynoid fat mass ratio and pre-peritoneal fat mass, were associated with narrower retinal arteriolar caliber (Pfat mass), but not with retinal venular caliber. Lipid and insulin levels were not associated with retinal vessel calibers. Higher C-reactive protein was associated with only wider retinal venular caliber (difference 0.10 SDS (95% CI 0.06, 0.14) per SDS increase in C-reactive protein). This latter association was not influenced by body mass index. Higher body fatness is associated with narrower retinal arteriolar caliber, whereas increased C-reactive protein levels are associated with wider retinal venular caliber. Increased fat mass and inflammation correlate with microvascular development from school-age onwards.

Effects of Low-Carbohydrate Diets Versus Low-Fat Diets on Metabolic Risk Factors: A Meta-Analysis of Randomized Controlled Clinical Trials

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Hu, Tian; Mills, Katherine T.; Yao, Lu; Demanelis, Kathryn; Eloustaz, Mohamed; Yancy, William S.; Kelly, Tanika N.; He, Jiang; Bazzano, Lydia A.

2012-01-01

The effects of low-carbohydrate diets (≤45% of energy from carbohydrates) versus low-fat diets (≤30% of energy from fat) on metabolic risk factors were compared in a meta-analysis of randomized controlled trials. Twenty-three trials from multiple countries with a total of 2,788 participants met the predetermined eligibility criteria (from January 1, 1966 to June 20, 2011) and were included in the analyses. Data abstraction was conducted in duplicate by independent investigators. Both low-carbohydrate and low-fat diets lowered weight and improved metabolic risk factors. Compared with participants on low-fat diets, persons on low-carbohydrate diets experienced a slightly but statistically significantly lower reduction in total cholesterol (2.7 mg/dL; 95% confidence interval: 0.8, 4.6), and low density lipoprotein cholesterol (3.7 mg/dL; 95% confidence interval: 1.0, 6.4), but a greater increase in high density lipoprotein cholesterol (3.3 mg/dL; 95% confidence interval: 1.9, 4.7) and a greater decrease in triglycerides (−14.0 mg/dL; 95% confidence interval: −19.4, −8.7). Reductions in body weight, waist circumference and other metabolic risk factors were not significantly different between the 2 diets. These findings suggest that low-carbohydrate diets are at least as effective as low-fat diets at reducing weight and improving metabolic risk factors. Low-carbohydrate diets could be recommended to obese persons with abnormal metabolic risk factors for the purpose of weight loss. Studies demonstrating long-term effects of low-carbohydrate diets on cardiovascular events were warranted. PMID:23035144

FGF19 regulates cell proliferation, glucose and bile acid metabolism via FGFR4-dependent and independent pathways.

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Ai-Luen Wu

Full Text Available Fibroblast growth factor 19 (FGF19 is a hormone-like protein that regulates carbohydrate, lipid and bile acid metabolism. At supra-physiological doses, FGF19 also increases hepatocyte proliferation and induces hepatocellular carcinogenesis in mice. Much of FGF19 activity is attributed to the activation of the liver enriched FGF Receptor 4 (FGFR4, although FGF19 can activate other FGFRs in vitro in the presence of the coreceptor βKlotho (KLB. In this report, we investigate the role of FGFR4 in mediating FGF19 activity by using Fgfr4 deficient mice as well as a variant of FGF19 protein (FGF19v which is specifically impaired in activating FGFR4. Our results demonstrate that FGFR4 activation mediates the induction of hepatocyte proliferation and the suppression of bile acid biosynthesis by FGF19, but is not essential for FGF19 to improve glucose and lipid metabolism in high fat diet fed mice as well as in leptin-deficient ob/ob mice. Thus, FGF19 acts through multiple receptor pathways to elicit pleiotropic effects in regulating nutrient metabolism and cell proliferation.

Anorexia Nervosa, Obesity and Bone Metabolism

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Misra, Madhusmita; Klibanski, Anne

2014-01-01

Anorexia nervosa and obesity are conditions at the extreme ends of the nutritional spectrum, associated with marked reductions versus increases respectively in body fat content. Both conditions are also associated with an increased risk for fractures. In anorexia nervosa, body composition and hormones secreted or regulated by body fat content are important determinants of low bone density, impaired bone structure and reduced bone strength. In addition, anorexia nervosa is characterized by increases in marrow adiposity and decreases in cold activated brown adipose tissue, both of which are related to low bone density. In obese individuals, greater visceral adiposity is associated with greater marrow fat, lower bone density and impaired bone structure. In this review, we discuss bone metabolism in anorexia nervosa and obesity in relation to adipose tissue distribution and hormones secreted or regulated by body fat content. PMID:24079076

Food Components Modulate Obesity and Energy Metabolism via the Transcriptional Regulation of Lipid-Sensing Nuclear Receptors.

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Goto, Tsuyoshi; Takahashi, Nobuyuki; Kawada, Teruo

2015-01-01

Obesity is a major risk factor for chronic diseases such as diabetes, cardiovascular diseases, and hypertension. Many modern people have a tendency to overeat owing to stress and loosening of self-control. Moreover, energy expenditure varies greatly among individuals. Scientific reduction of obesity is important under these circumstances. Furthermore, recent research on molecular levels has clarified the differentiation of adipocytes, the level of subsequent fat accumulation, and the secretion of the biologically active adipokines by adipocytes. Adipose tissues and obesity have become the most important target for the prevention and treatment of many chronic diseases. We have identified various food-derived compounds modulating nuclear receptors, especially peroxisome proliferators-activated receptor(PPAR), in the regulation of energy metabolism and obesity. In this review, we discuss the PPARs that are most important in obesity and energy metabolism.

Association of fat to lean mass ratio with metabolic dysfunction in women with polycystic ovary syndrome.

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Ezeh, Uche; Pall, Marita; Mathur, Ruchi; Azziz, Ricardo

2014-07-01

Are differences in metabolic dysfunction between polycystic ovary syndrome (PCOS) and control women related to differences in their fat to lean mass (F/L) ratio? Compared with controls of similar body mass index (BMI), women with PCOS demonstrate adverse body composition characterized by increased whole body fat relative to lean mass (i.e. a higher F/L ratio), which is associated with differences in metabolic dysfunction between the two groups. Previous studies examining body composition and insulin resistance (IR) in PCOS have yielded conflicting results. Excess total fat mass (i.e. fat mass index [fat BMI]) correlates with IR, whereas increased total lean mass (i.e. lean BMI) has been associated with higher insulin sensitivity. However, the role of the F/L ratio, which integrates the antagonistic effects of both fat and lean mass depots, on IR in PCOS, has not been investigated. We conducted a prospective cross-sectional study of 120 women between the ages of 22-44 years to study the relation of the F/L ratio with measures of insulin action and secretion in both steady and dynamic states. Sixty PCOS (by NIH, 1990 criteria) and 60 control (age, race and BMI-matched) women were prospectively studied for body composition (by bioelectrical impedance analysis [BIA]) and basal IR and insulin secretion by the homeostasis model assessment (HOMA-IR and HOMA-%β-cell function, respectively) in a tertiary care academic referral center. A subset of 12 PCOS and 12 matched control women also underwent a modified frequently sampled intravenous glucose tolerance test (FSIVGTT) to determine glucose uptake and insulin secretion in dynamic state. Our results indicate that women with PCOS demonstrated greater degrees of hyperandrogenism, and higher waist-to-hip ratio (WHR), %body fat, fat BMI, F/L, fasting insulin levels, and HOMA-IR and HOMA-%β-cell values, than controls. In models adjusted for WHR and free testosterone and diagnostic groups, fasting insulin levels, HOMA-IR, and

Interleukin-1β regulates fat-liver crosstalk in obesity by auto-paracrine modulation of adipose tissue inflammation and expandability.

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Ori Nov

Full Text Available The inflammasome has been recently implicated in obesity-associated dys-metabolism. However, of its products, the specific role of IL-1β was clinically demonstrated to mediate only the pancreatic beta-cell demise, and in mice mainly the intra-hepatic manifestations of obesity. Yet, it remains largely unknown if IL-1β, a cytokine believed to mainly function locally, could regulate dysfunctional inter-organ crosstalk in obesity. Here we show that High-fat-fed (HFF mice exhibited a preferential increase of IL-1β in portal compared to systemic blood. Moreover, portally-drained mesenteric fat transplantation from IL-1βKO donors resulted in lower pyruvate-glucose flux compared to mice receiving wild-type (WT transplant. These results raised a putative endocrine function for visceral fat-derived IL-1β in regulating hepatic gluconeogenic flux. IL-1βKO mice on HFF exhibited only a minor or no increase in adipose expression of pro-inflammatory genes (including macrophage M1 markers, Mac2-positive crown-like structures and CD11b-F4/80-double-positive macrophages, all of which were markedly increased in WT-HFF mice. Further consistent with autocrine/paracrine functions of IL-1β within adipose tissue, adipose tissue macrophage lipid content was increased in WT-HFF mice, but significantly less in IL-1βKO mice. Ex-vivo, adipose explants co-cultured with primary hepatocytes from WT or IL-1-receptor (IL-1RI-KO mice suggested only a minor direct effect of adipose-derived IL-1β on hepatocyte insulin resistance. Importantly, although IL-1βKOs gained weight similarly to WT-HFF, they had larger fat depots with similar degree of adipocyte hypertrophy. Furthermore, adipogenesis genes and markers (pparg, cepba, fabp4, glut4 that were decreased by HFF in WT, were paradoxically elevated in IL-1βKO-HFF mice. These local alterations in adipose tissue inflammation and expansion correlated with a lower liver size, less hepatic steatosis, and preserved insulin

Metabolic reprogramming through fatty acid transport protein 1 (FATP1 regulates macrophage inflammatory potential and adipose inflammation

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Amy R. Johnson

2016-07-01

Full Text Available Objective: A novel approach to regulate obesity-associated adipose inflammation may be through metabolic reprogramming of macrophages (MΦs. Broadly speaking, MΦs dependent on glucose are pro-inflammatory, classically activated MΦs (CAM, which contribute to adipose inflammation and insulin resistance. In contrast, MΦs that primarily metabolize fatty acids are alternatively activated MΦs (AAM and maintain tissue insulin sensitivity. In actuality, there is much flexibility and overlap in the CAM-AAM spectrum in vivo dependent upon various stimuli in the microenvironment. We hypothesized that specific lipid trafficking proteins, e.g. fatty acid transport protein 1 (FATP1, would direct MΦ fatty acid transport and metabolism to limit inflammation and contribute to the maintenance of adipose tissue homeostasis. Methods: Bone marrow derived MΦs (BMDMs from Fatp1−/− and Fatp1+/+ mice were used to investigate FATP1-dependent substrate metabolism, bioenergetics, metabolomics, and inflammatory responses. We also generated C57BL/6J chimeric mice by bone marrow transplant specifically lacking hematopoetic FATP1 (Fatp1B−/− and controls Fatp1B+/+. Mice were challenged by high fat diet (HFD or low fat diet (LFD and analyses including MRI, glucose and insulin tolerance tests, flow cytometric, histologic, and protein quantification assays were conducted. Finally, an FATP1-overexpressing RAW 264.7 MΦ cell line (FATP1-OE and empty vector control (FATP1-EV were developed as a gain of function model to test effects on substrate metabolism, bioenergetics, metabolomics, and inflammatory responses. Results: Fatp1 is downregulated with pro-inflammatory stimulation of MΦs. Fatp1−/− BMDMs and FATP1-OE RAW 264.7 MΦs demonstrated that FATP1 reciprocally controled metabolic flexibility, i.e. lipid and glucose metabolism, which was associated with inflammatory response. Supporting our previous work demonstrating the positive relationship between glucose

Effects of alfalfa meal on carcase quality and fat metabolism of Muscovy ducks.

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Jiang, J F; Song, X M; Huang, X; Wu, J L; Zhou, W D; Zheng, H C; Jiang, Y Q

2012-01-01

1. The effects of alfalfa meal on carcase quality and fat metabolism of Muscovy duck were evaluated. The objective of this research was to establish whether alfalfa meal can reduce fat content and improve carcase quality of Muscovy duck. Animal products with a high fat content present a risk factor for many diseases. Reducing fat content in poultry products is an important goal for the poultry industry. 2. A total of 240 14-d-old white Muscovy ducks were selected and randomly allocated to 1 of 4 dietary treatments containing 0, 3, 6, and 9% of alfalfa meal for 5 weeks. Growth performances were recorded and carcase characteristics and lipid parameters were analysed. 3. Results showed that 3, 6, and 9% alfalfa meal in diet had no significant effects on growth performance of Muscovy ducks from 14 to 49 d of age. Ducks given 3, 6, and 9% alfalfa meal had significantly higher dressing percentage and lower abdominal fat percentage compared with those given no alfalfa meal. Ducks given 9% alfalfa meal had higher breast meat percentage compared with those given no alfalfa meal. The concentrations of triglyceride, total cholesterol, low density lipoprotein (LDL), very low density lipoprotein (VLDL) and free fatty acid in serum of ducks fed on alfalfa meal decreased. Alfalfa meal in the diet decreased abdominal fat percentage and improved carcase traits of Muscovy duck. 4. The study showed that dietary alfalfa meal decreased abdominal fat percentage and improved carcase traits, without an adverse effect on performance.

Pre- and post-natal nutritional factors in the metabolic regulation of obesity

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E. Villanueva-Ortega

2017-04-01

Full Text Available In recent decades there has been a very significant increase in obesity in most developing countries. In addition to environmental, genetic and hormonal factors, nutritional and maternal environment factors influencing critical periods of foetal development have acquired increasing significance since the thrifty phenotype theory was described by Harles and Barker and epidemiological studies demonstrated that perinatal conditions may modify individuals’ future metabolic responses via genomic reprogramming. Perinatal programming corresponds to a critical and accelerated period of developmental plasticity from preconception through early postnatal life. This characteristic may also have a long-term influence on metabolic health and obesity. Epigenetic modifications favour the survival of the individual in critical periods when nutritional restriction is established, but exerts long-term risks, as metabolic programming tracks into infancy and adulthood and induces fat mass accumulation, particularly if energy consumption is exceeded. Although the mechanisms are not yet fully understood, it is evident that hormonal factors such as insulin and leptin may influence the programming of hypothalamic circuits for energy balance regulation. Nutritional interventions in animal models at critical stages of development have demonstrated that microenvironmental modifications might induce a permanent modulation of the progeny genome expression via epigenetic mechanisms. A transgenerational transmission of obesity has been proposed.

A High Fat Diet during Adolescence in Male Rats Negatively Programs Reproductive and Metabolic Function Which Is Partially Ameliorated by Exercise

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Carlos A. Ibáñez

2017-11-01

Full Text Available An interaction between obesity, impaired glucose metabolism and sperm function in adults has been observed but it is not known whether exposure to a diet high in fat during the peri-pubertal period can have longstanding programmed effects on reproductive function and gonadal structure. This study examined metabolic and reproductive function in obese rats programmed by exposure to a high fat (HF diet during adolescence. The effect of physical training (Ex in ameliorating this phenotype was also assessed. Thirty-day-old male Wistar rats were fed a HF diet (35% lard w/w for 30 days then subsequently fed a normal fat diet (NF for a 40-day recovery period. Control animals were fed a NF diet throughout life. At 70 days of life, animals started a low frequency moderate exercise training that lasted 30 days. Control animals remained sedentary (Se. At 100 days of life, biometric, metabolic and reproductive parameters were evaluated. Animals exposed to HF diet showed greater body weight, glucose intolerance, increased fat tissue deposition, reduced VO2max and reduced energy expenditure. Consumption of the HF diet led to an increase in the number of abnormal seminiferous tubule and a reduction in seminiferous epithelium height and seminiferous tubular diameter, which was reversed by moderate exercise. Compared with the NF-Se group, a high fat diet decreased the number of seminiferous tubules in stages VII-VIII and the NF-Ex group showed an increase in stages XI-XIII. HF-Se and NF-Ex animals showed a decreased number of spermatozoa in the cauda epididymis compared with animals from the NF-Se group. Animals exposed to both treatments (HF and Ex were similar to all the other groups, thus these alterations induced by HF or Ex alone were partially prevented. Physical training reduced fat pad deposition and restored altered reproductive parameters. HF diet consumption during the peri-pubertal period induces long-term changes on metabolism and the reproductive

Undesirable compounds in oils and fats: analysis and regulation

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Lacoste Florence

2003-03-01

Full Text Available The aim of this paper is to present, for some undesirable compounds representative of the major origins, a comparison between the efficiency of the analytical methods used (sensitivity, precision and existing regulations. An idea of the different origins of the presence of undesirable compounds in oils and fats is given. Then a focus is done on guidelines on contaminant analysis provided by European directives or Codex Alimentarius. The reliability of some existing test methods compared to regulations is also examined: lead, hexane, polycyclic aromatic hydrocarbons, and pesticide residues.

Pancreatic Fat Is Associated With Metabolic Syndrome and Visceral Fat but Not Beta-Cell Function or Body Mass Index in Pediatric Obesity.

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Staaf, Johan; Labmayr, Viktor; Paulmichl, Katharina; Manell, Hannes; Cen, Jing; Ciba, Iris; Dahlbom, Marie; Roomp, Kirsten; Anderwald, Christian-Heinz; Meissnitzer, Matthias; Schneider, Reinhard; Forslund, Anders; Widhalm, Kurt; Bergquist, Jonas; Ahlström, Håkan; Bergsten, Peter; Weghuber, Daniel; Kullberg, Joel

2017-03-01

Adolescents with obesity have increased risk of type 2 diabetes and metabolic syndrome (MetS). Pancreatic fat has been related to these conditions; however, little is known about associations in pediatric obesity. The present study was designed to explore these associations further. We examined 116 subjects, 90 with obesity. Anthropometry, MetS, blood samples, and oral glucose tolerance tests were assessed using standard techniques. Pancreatic fat fraction (PFF) and other fat depots were quantified using magnetic resonance imaging. The PFF was elevated in subjects with obesity. No association between PFF and body mass index-standard deviation score (BMI-SDS) was found in the obesity subcohort. Pancreatic fat fraction correlated to Insulin Secretion Sensitivity Index-2 and Homeostatic Model Assessment of Insulin Resistance in simple regression; however, when using adjusted regression and correcting for BMI-SDS and other fat compartments, PFF correlated only to visceral adipose tissue and fasting glucose. Highest levels of PFF were found in subjects with obesity and MetS. In adolescents with obesity, PFF is elevated and associated to MetS, fasting glucose, and visceral adipose tissue but not to beta-cell function, glucose tolerance, or BMI-SDS. This study demonstrates that conclusions regarding PFF and its associations depend on the body mass features of the cohort.

Role of the BAHD1 Chromatin-Repressive Complex in Placental Development and Regulation of Steroid Metabolism.

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Goran Lakisic

2016-03-01

Full Text Available BAHD1 is a vertebrate protein that promotes heterochromatin formation and gene repression in association with several epigenetic regulators. However, its physiological roles remain unknown. Here, we demonstrate that ablation of the Bahd1 gene results in hypocholesterolemia, hypoglycemia and decreased body fat in mice. It also causes placental growth restriction with a drop of trophoblast glycogen cells, a reduction of fetal weight and a high neonatal mortality rate. By intersecting transcriptome data from murine Bahd1 knockout (KO placentas at stages E16.5 and E18.5 of gestation, Bahd1-KO embryonic fibroblasts, and human cells stably expressing BAHD1, we also show that changes in BAHD1 levels alter expression of steroid/lipid metabolism genes. Biochemical analysis of the BAHD1-associated multiprotein complex identifies MIER proteins as novel partners of BAHD1 and suggests that BAHD1-MIER interaction forms a hub for histone deacetylases and methyltransferases, chromatin readers and transcription factors. We further show that overexpression of BAHD1 leads to an increase of MIER1 enrichment on the inactive X chromosome (Xi. In addition, BAHD1 and MIER1/3 repress expression of the steroid hormone receptor genes ESR1 and PGR, both playing important roles in placental development and energy metabolism. Moreover, modulation of BAHD1 expression in HEK293 cells triggers epigenetic changes at the ESR1 locus. Together, these results identify BAHD1 as a core component of a chromatin-repressive complex regulating placental morphogenesis and body fat storage and suggest that its dysfunction may contribute to several human diseases.

Metabolic risk factors in mice divergently selected for BMR fed high fat and high carb diets.

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Sadowska, Julita; Gębczyński, Andrzej K; Konarzewski, Marek

2017-01-01

Factors affecting contribution of spontaneous physical activity (SPA; activity associated with everyday tasks) to energy balance of humans are not well understood, as it is not clear whether low activity is related to dietary habits, precedes obesity or is a result of thereof. In particular, human studies on SPA and basal metabolic rates (BMR, accounting for >50% of human energy budget) and their associations with diet composition, metabolic thrift and obesity are equivocal. To clarify these ambiguities we used a unique animal model-mice selected for divergent BMR rates (the H-BMR and L-BMR line type) presenting a 50% between-line type difference in the primary selected trait. Males of each line type were divided into three groups and fed either a high fat, high carb or a control diet. They then spent 4 months in individual cages under conditions emulating human "sedentary lifestyle", with SPA followed every month and measurements of metabolic risk indicators (body fat mass %, blood lipid profile, fasting blood glucose levels and oxidative damage in the livers, kidneys and hearts) taken at the end of study. Mice with genetically determined high BMR assimilated more energy and had higher SPA irrespective of type of diet. H-BMR individuals were characterized by lower dry body fat mass %, better lipid profile and lower fasting blood glucose levels, but higher oxidative damage in the livers and hearts. Genetically determined high BMR may be a protective factor against diet-induced obesity and most of the metabolic syndrome indicators. Elevated spontaneous activity is correlated with high BMR, and constitutes an important factor affecting individual capability to sustain energy balance even under energy dense diets.

Nuclear hormone receptor NHR-49 controls fat consumption and fatty acid composition in C. elegans.

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Marc R Van Gilst

2005-02-01

Full Text Available Mammalian nuclear hormone receptors (NHRs, such as liver X receptor, farnesoid X receptor, and peroxisome proliferator-activated receptors (PPARs, precisely control energy metabolism. Consequently, these receptors are important targets for the treatment of metabolic diseases, including diabetes and obesity. A thorough understanding of NHR fat regulatory networks has been limited, however, by a lack of genetically tractable experimental systems. Here we show that deletion of the Caenorhabditis elegans NHR gene nhr-49 yielded worms with elevated fat content and shortened life span. Employing a quantitative RT-PCR screen, we found that nhr-49 influenced the expression of 13 genes involved in energy metabolism. Indeed, nhr-49 served as a key regulator of fat usage, modulating pathways that control the consumption of fat and maintain a normal balance of fatty acid saturation. We found that the two phenotypes of the nhr-49 knockout were linked to distinct pathways and were separable: The high-fat phenotype was due to reduced expression of enzymes in fatty acid beta-oxidation, and the shortened adult life span resulted from impaired expression of a stearoyl-CoA desaturase. Despite its sequence relationship with the mammalian hepatocyte nuclear factor 4 receptor, the biological activities of nhr-49 were most similar to those of the mammalian PPARs, implying an evolutionarily conserved role for NHRs in modulating fat consumption and composition. Our findings in C. elegans provide novel insights into how NHR regulatory networks are coordinated to govern fat metabolism.

Nuclear hormone receptor NHR-49 controls fat consumption and fatty acid composition in C. elegans.

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Van Gilst, Marc R; Hadjivassiliou, Haralambos; Jolly, Amber; Yamamoto, Keith R

2005-02-01

Mammalian nuclear hormone receptors (NHRs), such as liver X receptor, farnesoid X receptor, and peroxisome proliferator-activated receptors (PPARs), precisely control energy metabolism. Consequently, these receptors are important targets for the treatment of metabolic diseases, including diabetes and obesity. A thorough understanding of NHR fat regulatory networks has been limited, however, by a lack of genetically tractable experimental systems. Here we show that deletion of the Caenorhabditis elegans NHR gene nhr-49 yielded worms with elevated fat content and shortened life span. Employing a quantitative RT-PCR screen, we found that nhr-49 influenced the expression of 13 genes involved in energy metabolism. Indeed, nhr-49 served as a key regulator of fat usage, modulating pathways that control the consumption of fat and maintain a normal balance of fatty acid saturation. We found that the two phenotypes of the nhr-49 knockout were linked to distinct pathways and were separable: The high-fat phenotype was due to reduced expression of enzymes in fatty acid beta-oxidation, and the shortened adult life span resulted from impaired expression of a stearoyl-CoA desaturase. Despite its sequence relationship with the mammalian hepatocyte nuclear factor 4 receptor, the biological activities of nhr-49 were most similar to those of the mammalian PPARs, implying an evolutionarily conserved role for NHRs in modulating fat consumption and composition. Our findings in C. elegans provide novel insights into how NHR regulatory networks are coordinated to govern fat metabolism.

Dietary fat modulation of mammary tumor growth and metabolism demonstrated by 31P-nuclear magnetic resonance

International Nuclear Information System (INIS)

Erickson, K.L.; Buckman, D.K.; Hubbard, N.E.; Ross, B.

1986-01-01

The relationship of dietary fat concentration and saturation on the growth and metabolic activity of line 168 was studied using syngeneic mice fed 6 experimental diets before and during tumor growth. Tumor latency was significantly greater for mice fed a diet containing the minimum of essential fatty acids (EFA, 0.5% corn oil) or 8% coconut oil (SF) than for mice fed 8 or 20% safflower oil (PUF) or 20% SF. Changes in dietary fat resulted in alterations of tumor cell and serum fatty acid composition but not the number of inflammatory cells infiltrating the tumor. 31 P-surface coil NMR was used to measure possible changes in tumor metabolism in vivo. Although pH decreased from 7.2 to 6.6 as the tumor volume increased, there was no difference in pH among dietary groups. There was an inverse relationship between both sugar phosphate (SP)/Pi and ATP/Pi ratios and tumor volume; those ratios for mice fed an EFA deficient or minimal EFA diet decreased at a different rate than ratios for mice fed diets with additional fat. Tumors of mice fed diets containing no or a low level (0.3%) of 18:2 had higher SP/ATP ratios than mice fed diets containing a moderate level (∼ 4%) of 18:2. Thus, high levels of dietary fat had a significant effect on promotion of mammary tumors during early stages of tumor growth. Differences in tumor volume associated with dietary fat may be related to changes in the levels of high energy phosphate metabolites

Fat, Sugar, and Bone Health: A Complex Relationship.

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Tian, Li; Yu, Xijie

2017-05-17

With people aging, osteoporosis is expected to increase notably. Nutritional status is a relatively easily-modified risk factor, associated with many chronic diseases, and is involved in obesity, diabetes, and coronary heart disease (CHD), along with osteoporosis. Nutrients, such as fats, sugars, and proteins, play a primary function in bone metabolism and maintaining bone health. In Western nations, diets are generally high in saturated fats, however, currently, the nutritional patterns dominating in China continue to be high in carbohydrates from starch, cereals, and sugars. Moreover, high fat or high sugar (fructose, glucose, or sucrose) impart a significant impact on bone structural integrity. Due to diet being modifiable, demonstrating the effects of nutrition on bone health can provide an approach for osteoporosis prevention. Most researchers have reported that a high-fat diet consumption is associated with bone mineral density (BMD) and, as bone strength diminishes, adverse microstructure changes occur in the cancellous bone compartment, which is involved with lipid metabolism modulation disorder and the alteration of the bone marrow environment, along with an increased inflammatory environment. Some studies, however, demonstrated that a high-fat diet contributes to achieving peak bone mass, along with microstructure, at a younger age. Contrary to these results, others have shown that a high-fructose diet consumption leads to stronger bones with a superior microarchitecture than those with the intake of a high-glucose diet and, at the same time, research indicated that a high-fat diet usually deteriorates cancellous bone parameters, and that the incorporation of fructose into a high-fat diet did not aggravate bone mass loss. High-fat/high-sucrose diets have shown both beneficial and detrimental influences on bone metabolism. Combined, these studies showed that nutrition exerts different effects on bone health. Thus, a better understanding of the regulation

Fat, Sugar, and Bone Health: A Complex Relationship

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Li Tian

2017-05-01

Full Text Available With people aging, osteoporosis is expected to increase notably. Nutritional status is a relatively easily-modified risk factor, associated with many chronic diseases, and is involved in obesity, diabetes, and coronary heart disease (CHD, along with osteoporosis. Nutrients, such as fats, sugars, and proteins, play a primary function in bone metabolism and maintaining bone health. In Western nations, diets are generally high in saturated fats, however, currently, the nutritional patterns dominating in China continue to be high in carbohydrates from starch, cereals, and sugars. Moreover, high fat or high sugar (fructose, glucose, or sucrose impart a significant impact on bone structural integrity. Due to diet being modifiable, demonstrating the effects of nutrition on bone health can provide an approach for osteoporosis prevention. Most researchers have reported that a high-fat diet consumption is associated with bone mineral density (BMD and, as bone strength diminishes, adverse microstructure changes occur in the cancellous bone compartment, which is involved with lipid metabolism modulation disorder and the alteration of the bone marrow environment, along with an increased inflammatory environment. Some studies, however, demonstrated that a high-fat diet contributes to achieving peak bone mass, along with microstructure, at a younger age. Contrary to these results, others have shown that a high-fructose diet consumption leads to stronger bones with a superior microarchitecture than those with the intake of a high-glucose diet and, at the same time, research indicated that a high-fat diet usually deteriorates cancellous bone parameters, and that the incorporation of fructose into a high-fat diet did not aggravate bone mass loss. High-fat/high-sucrose diets have shown both beneficial and detrimental influences on bone metabolism. Combined, these studies showed that nutrition exerts different effects on bone health. Thus, a better understanding of

The Fat-Dachsous signaling pathway regulates growth of horns in Trypoxylus dichotomus, but does not affect horn allometry.

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Hust, James; Lavine, Mark D; Worthington, Amy M; Zinna, Robert; Gotoh, Hiroki; Niimi, T; Lavine, Laura

Males of the Asian rhinoceros beetle, Trypoxylus dichotomus, possess exaggerated head and thoracic horns that scale dramatically out of proportion to body size. While studies of insulin signaling suggest that this pathway regulates nutrition-dependent growth including exaggerated horns, what regulates disproportionate growth has yet to be identified. The Fat signaling pathway is a potential candidate for regulating disproportionate growth of sexually-selected traits, a hypothesis we advanced in a previous paper (Gotoh et al., 2015). To investigate the role of Fat signaling in the growth and scaling of the sexually dimorphic, condition-dependent traits of the in the Asian rhinoceros beetle T. dichotomus, we used RNA interference to knock down expression of fat and its co-receptor dachsous. Knockdown of fat, and to a lesser degree dachsous, caused shortening and widening of appendages, including the head and thoracic horns. However, scaling of horns to body size was not affected. Our results show that Fat signaling regulates horn growth in T. dichotomus as it does in appendage growth in other insects. However, we provide evidence that Fat signaling does not mediate the disproportionate, positive allometric growth of horns in T. dichotomus. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Metabolic Implications of Glucocorticoids in a High-Fat Diet Setting and the Counter-Effects of Exercise

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Emily C. Dunford

2016-12-01

Full Text Available Glucocorticoids (GCs are steroid hormones, naturally produced by activation of the hypothalamic-pituitary-adrenal (HPA axis, that mediate the immune and metabolic systems. Synthetic GCs are used to treat a number of inflammatory conditions and diseases including lupus and rheumatoid arthritis. Generally, chronic or high dose GC administration is associated with side effects such as steroid-induced skeletal muscle loss, visceral adiposity, and diabetes development. Patients who are taking exogenous GCs could also be more susceptible to poor food choices, but the effect that increasing fat consumption in combination with elevated exogenous GCs has only recently been investigated. Overall, these studies show that the damaging metabolic effects initiated through exogenous GC treatment are significantly amplified when combined with a high fat diet (HFD. Rodent studies of a HFD and elevated GCs demonstrate more glucose intolerance, hyperinsulinemia, visceral adiposity, and skeletal muscle lipid deposition when compared to rodents subjected to either treatment on its own. Exercise has recently been shown to be a viable therapeutic option for GC-treated, high-fat fed rodents, with the potential mechanisms still being examined. Clinically, these mechanistic studies underscore the importance of a low fat diet and increased physical activity levels when individuals are given a course of GC treatment.

Kefir Peptides Prevent Hyperlipidemia and Obesity in High-Fat-Diet-Induced Obese Rats via Lipid Metabolism Modulation.

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Tung, Yu-Tang; Chen, Hsiao-Ling; Wu, Hsin-Shan; Ho, Mei-Hsuan; Chong, Kowit-Yu; Chen, Chuan-Mu

2018-02-01

Obesity has reached epidemic proportions worldwide. Obesity is a complex metabolic disorder that is linked to numerous serious health complications with high morbidity. The present study evaluated the effects of kefir peptides on high fat diet (HFD)-induced obesity in rats. Kefir peptides markedly improved obesity, including body weight gain, inflammatory reactions and the formation of adipose tissue fat deposits around the epididymis and kidney, and adipocyte size. Treating high fat diet (HFD)-induced obese rats with kefir peptides significantly reduced the fatty acid synthase protein and increased the p-acetyl-CoA carboxylase protein to block lipogenesis in the livers. Kefir peptides also increased fatty acid oxidation by increasing the protein expressions of phosphorylated AMP-activated protein kinase, peroxisome proliferator-activated receptor-α, and hepatic carnitine palmitoyltransferase-1 in the livers. In addition, administration of kefir peptides significantly decreased the inflammatory response (TNF-α, IL-1β, and TGF-β) to modulate oxidative damage. These results demonstrate that kefir peptides treatment improves obesity via inhibition of lipogenesis, modulation of oxidative damage, and stimulation of lipid oxidation. Therefore, kefir peptides may act as an anti-obesity agent to prevent body fat accumulation and obesity-related metabolic diseases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Relationship between delayed embryonic development and metabolic factors and fat deposition in fruit bat Cynopterus sphinx.

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Banerjee, Arnab; Meenakumari, K J; Krishna, Amitabh

2007-01-01

The present study was undertaken in the fruit bat Cynopterus sphinx, which breeds twice in quick succession at Varanasi, India. Its gestation period varies significantly in the two successive pregnancies of the year owing to delayed embryonic development during the first (winter) pregnancy. The primary aim of the present study was to determine the role of metabolic factors in delayed embryonic development in the fruit bat C. sphinx. Variation in bodyweight, fat deposition, oxygen (O(2)) consumption rate, basal metabolic rate (BMR), body temperature (Tb) and hepatic succinate dehydrogenase (SDH) activity, along with circulating levels of thyroid hormones (tri-iodothyronine and thyroxine), were examined as metabolic factors during the two successive pregnancies in C. sphinx. The increase in bodyweight observed in November was due to accumulation of white adipose tissue in the posterior abdominal region. A significant decline in O(2) consumption rate, BMR, Tb and SDH activity was found in early winter in November-December, which coincides closely with the period of fat accumulation and with the period of delayed embryonic development in C. sphinx. A significantly higher O(2) consumption rate, BMR, Tb and SDH activity was noted during the second pregnancy in, when embryonic development was relatively faster. Thyroid hormone levels were high during the period of embryonic delay compared with levels during the remaining months. The results of the present study suggest that the delayed embryonic development in C. sphinx during early winter may be due to a low O(2) consumption rate, BMR, Tb and SDH activity in November-December. The energy saved by suppressing embryonic development in this species may be advantageous for fat accumulation. Increased thyroid hormone levels during the early winter period might facilitate fat accumulation in C. sphinx.

Stressed-induced TMEM135 protein is part of a conserved genetic network involved in fat storage and longevity regulation in Caenorhabditis elegans.

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Vernat J Exil

2010-12-01

Full Text Available Disorders of mitochondrial fat metabolism lead to sudden death in infants and children. Although survival is possible, the underlying molecular mechanisms which enable this outcome have not yet been clearly identified. Here we describe a conserved genetic network linking disorders of mitochondrial fat metabolism in mice to mechanisms of fat storage and survival in Caenorhabditis elegans (C. elegans. We have previously documented a mouse model of mitochondrial very-long chain acyl-CoA dehydrogenase (VLCAD deficiency. We originally reported that the mice survived birth, but, upon exposure to cold and fasting stresses, these mice developed cardiac dysfunction, which greatly reduced survival. We used cDNA microarrays to outline the induction of several markers of lipid metabolism in the heart at birth in surviving mice. We hypothesized that the induction of fat metabolism genes in the heart at birth is part of a regulatory feedback circuit that plays a critical role in survival. The present study uses a dual approach employing both C57BL/6 mice and the nematode, C. elegans, to focus on TMEM135, a conserved protein which we have found to be upregulated 4.3 (±0.14-fold in VLCAD-deficient mice at birth. Our studies have demonstrated that TMEM135 is highly expressed in mitochondria and in fat-loaded tissues in the mouse. Further, when fasting and cold stresses were introduced to mice, we observed 3.25 (±0.03- and 8.2 (±0.31-fold increases in TMEM135 expression in the heart, respectively. Additionally, we found that deletion of the tmem135 orthologue in C. elegans caused a 41.8% (±2.8% reduction in fat stores, a reduction in mitochondrial action potential and decreased longevity of the worm. In stark contrast, C. elegans transgenic animals overexpressing TMEM-135 exhibited increased longevity upon exposure to cold stress. Based on these results, we propose that TMEM135 integrates biological processes involving fat metabolism and energy expenditure in

Short-term high-fat diet alters postprandial glucose metabolism and circulating vascular cell adhesion molecule-1 in healthy males.

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Numao, Shigeharu; Kawano, Hiroshi; Endo, Naoya; Yamada, Yuka; Takahashi, Masaki; Konishi, Masayuki; Sakamoto, Shizuo

2016-08-01

Short-term intake of a high-fat diet aggravates postprandial glucose metabolism; however, the dose-response relationship has not been investigated. We hypothesized that short-term intake of a eucaloric low-carbohydrate/high-fat diet (LCHF) would aggravate postprandial glucose metabolism and circulating adhesion molecules in healthy males. Seven healthy young males (mean ± SE; age: 26 ± 1 years) consumed either a eucaloric control diet (C, approximately 25% fats), a eucaloric intermediate-carbohydrate/intermediate-fat diet (ICIF, approximately 50% fats), or an LCHF (approximately 70% fats) for 3 days. An oral meal tolerance test (MTT) was performed after the 3-day dietary intervention. The concentrations of plasma glucose, insulin, glucagon-like peptide-1 (GLP-1), intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 (VCAM-1) were determined at rest and during MTT. The incremental area under the curve (iAUC) of plasma glucose concentration during MTT was significantly higher in LCHF than in C (P = 0.009). The first-phase insulin secretion indexes were significantly lower in LCHF than in C (P = 0.04). Moreover, the iAUC of GLP-1 and VCAM-1 concentrations was significantly higher in LCHF than in C (P = 0.014 and P = 0.04, respectively). The metabolites from ICIF and C were not significantly different. In conclusion, short-term intake of eucaloric diet containing a high percentage of fats in healthy males excessively increased postprandial glucose and VCAM-1 concentrations and attenuated first-phase insulin release.

Vagus nerve contributes to metabolic syndrome in high-fat diet-fed young and adult rats.

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Barella, Luiz F; Miranda, Rosiane A; Franco, Claudinéia C S; Alves, Vander S; Malta, Ananda; Ribeiro, Tatiane A S; Gravena, Clarice; Mathias, Paulo C F; de Oliveira, Júlio C

2015-01-01

What is the central question of this study? Different nerve contributes periods of life are known for their differential sensitivity to interventions, and increased parasympathetic activity affects the development and maintenance of obesity. Thus, we evaluated the involvement of the vagus nerve by performing a vagotomy in young or adult rats that were offered an obesogenic high-fat diet. What is the main finding and its importance? Although the accumulation of adipose tissue decreased in both younger and older groups, the younger rats showed a greater response to the effects of vagotomy in general. In addition to the important role of the parasympathetic activity, we suggest that the vagus nerve contributes to the condition of obesity. Obesity has become a global problem, and this condition develops primarily because of an imbalance between energy intake and expenditure. The high complexity involved in the regulation of energy metabolism results from several factors besides endocrine factors. It has been suggested that obesity could be caused by an imbalance in the autonomous nervous system, which could lead to a condition of high parasympathetic activity in counterpart to low sympathetic tonus. High-fat (HF) diets have been used to induce obesity in experimental animals, and their use in animals leads to insulin resistance, hyperinsulinaemia and high parasympathetic activity, among other disorders. The aim of this work was to evaluate the effects of a vagotomy performed at the initiation of a HF diet at two different stages of life, weaning and adulthood. The vagotomy reduced parasympathetic activity (-32 and -51% in normal fat-fed rats and -43 and -55% in HF diet-fed rats; P fat depots (-17 and -33%, only in HF diet-fed rats; P fat diet-fed rats exhibited fasting hyperinsulinaemia (fivefold higher in young rats and threefold higher in older rats; P diet-fed groups was not altered in the vagotomized rats. We suggest that the vagus nerve, in addition to the

A progesterone-brown fat axis is involved in regulating fetal growth.

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McIlvride, Saraid; Mushtaq, Aleena; Papacleovoulou, Georgia; Hurling, Chloe; Steel, Jennifer; Jansen, Eugène; Abu-Hayyeh, Shadi; Williamson, Catherine

2017-01-01

Pregnancy is associated with profound maternal metabolic changes, necessary for the growth and development of the fetus, mediated by reproductive signals acting on metabolic organs. However, the role of brown adipose tissue (BAT) in regulating gestational metabolism is unknown. We show that BAT

Weight Changes and Metabolic Outcomes in Calorie-Restricted Obese Mice Fed High-Fat Diets Containing Corn or Flaxseed Oil: Physiological Role of Sugar Replacement with Polyphenol-Rich Grape.

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Ansar, Hastimansooreh; Zamaninour, Negar; Djazayery, Abolghassem; Pishva, Hamideh; Vafa, Mohammadreza; Mazaheri Nezhad Fard, Ramin; Dilmaghanian, Aydin; Mirzaei, Khadijeh; Shidfar, Farzad

2017-08-01

Because diet components are important during dieting in obesity treatment, we examined possible beneficial effects of substituting corn oil and sugar with flaxseed oil and grape in calorie-restricted high-fat diets on weight changes as well as improvement in some metabolic markers and related gene expression. Seventy-five C57BL/6J male mice were given free access to a high-fat (36% of energy from fat) diet containing corn oil plus sugar (CO + S). After 11 weeks, 15 mice were sacrificed and another 60 were divided among 4 high-fat diet groups with 30% calorie restriction (CR) for the next 12 weeks. The diets contained corn oil (CO) or flaxseed oil (FO) with sugar (S) or grape (G). Despite CR, a weight loss trend was observed only during the first 4 weeks in all groups. CR did not significantly increase SIRT1 gene expression. Higher liver weight was observed in mice consuming FO (p sugar (FBS) was significantly higher than in CO + G-CR. Grape intake increased Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) expression and decreased insulin resistance in CO + G-CR. Sugar replacement with polyphenol-rich grape along with CR improved glucose homeostasis, and substituting corn oil with flaxseed oil in obese mice reduced fat mass, but even with no change in adiponectin levels it could not decrease insulin resistance. However, none of the food item combinations facilitated weight reduction in the long-term CR. Therefore, regardless of the total calorie intake, different diet components and fat contents may have unexpected effects on metabolic regulation.

Corn silk extract improves cholesterol metabolism in C57BL/6J mouse fed high-fat diets.

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Cha, Jae Hoon; Kim, Sun Rim; Kang, Hyun Joong; Kim, Myung Hwan; Ha, Ae Wha; Kim, Woo Kyoung

2016-10-01

Corn silk (CS) extract contains large amounts of maysin, which is a major flavonoid in CS. However, studies regarding the effect of CS extract on cholesterol metabolism is limited. Therefore, the purpose of this study was to determine the effect of CS extract on cholesterol metabolism in C57BL/6J mouse fed high-fat diets. Normal-fat group fed 7% fat diet, high-fat (HF) group fed 25% fat diet, and high-fat with corn silk (HFCS) group were orally administered CS extract (100 mg/kg body weight) daily. Serum and hepatic levels of total lipids, triglycerides, and total cholesterol as well as serum free fatty acid, glucose, and insulin levels were determined. The mRNA expression levels of acyl-CoA: cholesterol acyltransferase (ACAT), cholesterol 7-alpha hydroxylase (CYP7A1), farnesoid X receptor (FXR), lecithin cholesterol acyltransferase (LCAT), low-density lipoprotein receptor, 3-hyroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase), adiponectin, leptin, and tumor necrosis factor α were determined. Oral administration of CS extract with HF improved serum glucose and insulin levels as well as attenuated HF-induced fatty liver. CS extracts significantly elevated mRNA expression levels of adipocytokines and reduced mRNA expression levels of HMG-CoA reductase, ACAT, and FXR. The mRNA expression levels of CYP7A1 and LCAT between the HF group and HFCS group were not statistically different. CS extract supplementation with a high-fat diet improves levels of adipocytokine secretion and glucose homeostasis. CS extract is also effective in decreasing the regulatory pool of hepatic cholesterol, in line with decreased blood and hepatic levels of cholesterol though modulation of mRNA expression levels of HMG-CoA reductase, ACAT, and FXR.

Fat body, fat pad and adipose tissues in invertebrates and vertebrates: the nexus

Science.gov (United States)

2014-01-01

The fat body in invertebrates was shown to participate in energy storage and homeostasis, apart from its other roles in immune mediation and protein synthesis to mention a few. Thus, sharing similar characteristics with the liver and adipose tissues in vertebrates. However, vertebrate adipose tissue or fat has been incriminated in the pathophysiology of metabolic disorders due to its role in production of pro-inflammatory cytokines. This has not been reported in the insect fat body. The link between the fat body and adipose tissue was examined in this review with the aim of determining the principal factors responsible for resistance to inflammation in the insect fat body. This could be the missing link in the prevention of metabolic disorders in vertebrates, occasioned by obesity. PMID:24758278

The Beneficial Effect of Anthocyanidin-Rich Vitis vinifera L. Grape Skin Extract on Metabolic Changes Induced by High-Fat Diet in Mice Involves Antiinflammatory and Antioxidant Actions.

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da Costa, Gisele França; Santos, Izabelle Barcellos; de Bem, Graziele Freitas; Cordeiro, Viviane Silva Cristino; da Costa, Cristiane Aguiar; de Carvalho, Lenize Costa Reis Marins; Ognibene, Dayane Teixeira; Resende, Angela Castro; de Moura, Roberto Soares

2017-10-01

We hypothesized that a polyphenol-rich extract from Vitis vinifera L. grape skin (GSE) may exert beneficial effects on obesity and related metabolic disorders induced by a high-fat diet (HFD). C57/BL6 mice were fed a standard diet (10% fat, control, and GSE groups) or an HFD (60% fat, high fat (HF), and HF + GSE) with or without GSE (200 mg/kg/day) for 12 weeks. GSE prevented weight gain; dyslipidemia; insulin resistance; the alterations in plasma levels of leptin, adiponectin, and resistin; and the deregulation of leptin and adiponectin expression in adipose tissue. These beneficial effects of GSE may be related to a positive modulation of insulin signaling proteins (IR, pIRS, PI3K, pAKT), pAMPK/AMPK ratio, and GLUT4 expression in muscle and adipose tissue. In addition, GSE prevented the oxidative damage, evidenced by the restoration of antioxidant activity and decrease of malondialdehyde and carbonyl levels in muscle and adipose tissue. Finally, GSE showed an anti-inflammatory action, evidenced by the reduced plasma and adipose tissue inflammatory markers (TNF-α, IL-6). Our results suggest that GSE prevented the obesity and related metabolic disorders in HF-fed mice by regulating insulin sensitivity and GLUT4 expression as well as by preventing the oxidative stress and inflammation in skeletal muscle and adipose tissue. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Acute vs chronic exposure to high fat diet leads to distinct regulation of PKA.

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London, Edra; Nesterova, Maria; Stratakis, Constantine A

2017-07-01

The cAMP-dependent protein kinase (PKA) is an essential regulator of lipid and glucose metabolism that plays a critical role in energy homeostasis. The impact of diet on PKA signaling has not been defined, although perturbations in individual PKA subunits are associated with changes in adiposity, physical activity and energy intake in mice and humans. We hypothesized that a high fat diet (HFD) would elicit peripheral and central alterations in the PKA system that would differ depending on length of exposure to HFD; these differences could protect against or promote diet-induced obesity (DIO). 12-week-old C57Bl/6J mice were randomly assigned to a regular diet or HFD and weighed weekly throughout the feeding studies (4 days, 14 weeks; respectively), and during killing. PKA activity and subunit expression were measured in liver, gonadal adipose tissue (AT) and brain. Acute HFD-feeding suppressed basal hepatic PKA activity. In contrast, hepatic and hypothalamic PKA activities were significantly increased after chronic HFD-feeding. Changes in AT were more subtle, and overall, altered PKA regulation in response to chronic HFD exposure was more profound in female mice. The suppression of hepatic PKA activity after 4 day HFD-feeding was indicative of a protective peripheral effect against obesity in the context of overnutrition. In response to chronic HFD-feeding, and with the development of DIO, dysregulated hepatic and hypothalamic PKA signaling was a signature of obesity that is likely to promote further metabolic dysfunction in mice. © 2017 Society for Endocrinology.

Activating Transcription Factor 3 Regulates Immune and Metabolic Homeostasis

Science.gov (United States)

Rynes, Jan; Donohoe, Colin D.; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek

2012-01-01

Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins. PMID:22851689

Activating transcription factor 3 regulates immune and metabolic homeostasis.

Science.gov (United States)

Rynes, Jan; Donohoe, Colin D; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek; Uhlirova, Mirka

2012-10-01

Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins.

Chronic High Fat Diet Consumption Impairs Metabolic Health of Male Mice.

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Morselli, Eugenia; Criollo, Alfredo; Rodriguez-Navas, Carlos; Clegg, Deborah J

We show that chronic high fat diet (HFD) feeding affects the hypothalamus of male but not female mice. In our study we demonstrate that palmitic acid and sphingolipids accumulate in the central nervous system of HFD-fed males. Additionally, we show that HFD-feeding reduces proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) thus reducing estrogen receptor α (ERα) and driving hypothalamic inflammation in male but not female mice. Hypothalamic inflammation correlates with markers of metabolic dysregulation as indicated by dysregulation in glucose intolerance and myocardial function. Lastly, we demonstrate that there are blockages in mitophagy and lipophagy in hypothalamic tissues in males. Our data suggest there is a sexually dimorphic response to chronic HDF exposure, females; despite gaining the same amount of body weight following HFD-feeding, appear to be protected from the adverse metabolic effects of the HFD.

Modifications of Western-type diet regarding protein, fat and sucrose levels as modulators of steroid metabolism and activity in liver.

Science.gov (United States)

Krawczyńska, Agata; Herman, Andrzej P; Antushevich, Hanna; Bochenek, Joanna; Dziendzikowska, Katarzyna; Gajewska, Alina; Gromadzka-Ostrowska, Joanna

2017-01-01

The aim of the study was to evaluate whether the modification of the Western-type diet (high-fat, high-sucrose diet rich in saturated fatty acids) considering macronutrients content would influence hepatic metabolism and activity of steroids. For 3 weeks Wistar rat were fed the Western-type diet (21% fat, 35% sucrose, 19% protein, lard) and its modifications regarding dietary protein (10 and 19%), fat (5 and 21%) and sucrose (0 and 35%) levels. The steroid 5α-reductase type 1 (Srd5a1) and androgen receptor (Ar) gene expression as well as testosterone (T) conversion towards 5α-reduced derivatives in liver were positively correlated with body weight gain. The Western-type diets with decreased protein content regardless of the sucrose level exerted the most negative effect on the antioxidant system decreasing catalase (Cat), sodium dismutase (Sod1) and glutathione peroxidase (Gpx1) gene expression as well as Cat and Gpx activity and total antioxidant status, simultaneously intensifying lipid peroxidation. The impaired antioxidant system was accompanied by decreased level of hepatic T metabolism towards estrogens: 17β-estradiol (E2) and estriol, and increased estrogen receptor type 1 (Esr1) gene expression. Liver Esr1 mRNA level was differently correlated with T (positively) and E2 (negatively) plasma levels. Whereas the fat reduction in Western-type diet restored the plasma proportion between T and E2. In conclusion it could be stated that Western-type diet modification relating to protein, sucrose and fat content can influence hepatic steroid metabolism and activity; however the estrogens and androgens metabolism in liver would be connected with impairment of liver function or catabolic activity, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

Glucose metabolic alterations in hippocampus of diabetes mellitus rats and the regulation of aerobic exercise.

Science.gov (United States)

Li, Jingjing; Liu, Beibei; Cai, Ming; Lin, Xiaojing; Lou, Shujie

2017-11-04

Diabetes could negatively affect the structures and functions of the brain, especially could cause the hippocampal dysfunction, however, the potential metabolic mechanism is unclear. The aim of this study was to investigate the changes of glucose metabolism in hippocampus of diabetes mellitus rats and the regulation of aerobic exercise, and to analyze the possible mechanisms. A rat model of type 2 diabetes mellitus was established by high-fat diet feeding in combination with STZ intraperitoneal injection, then 4 weeks of aerobic exercise was conducted. The glucose metabolites and key enzymes involved in glucose metabolism in hippocampus were respectively detected by GC/MS based metabolomics and western blot. Metabolomics results showed that compared with control rats, the level of citric acid was significantly decreased, while the levels of lactic acid, ribose 5-phosphate, xylulose 5-phosphate and glucitol were significantly increased in the diabetic rat. Compared with diabetic rats, the level of citric acid was significantly increased, while the lactic acid, ribose 5-phosphate and xylulose 5-phosphate were significantly decreased in the diabetic exercise rats. Western blot results showed that lower level of citrate synthase and oxoglutarate dehydrogenase, higher level of aldose reductase and glucose 6-phosphatedehydrogenase were found in the diabetic rats when compared to control rats. After 4 weeks of aerobic exercise, citrate synthase was upregulated and glucose 6-phosphatedehydrogenase was downregulated in the diabetic rats. These results suggest that diabetes could cause abnormal glucose metabolism, and aerobic exercise plays an important role in regulating diabetes-induced disorder of glucose metabolism in the hippocampus. Copyright © 2017 Elsevier B.V. All rights reserved.

Hypothalamic PGC-1 alpha Protects Against High-Fat Diet Exposure by Regulating ER alpha

NARCIS (Netherlands)

Morselli, Eugenia; Fuente-Martin, Esther; Finan, Brian; Kim, Min; Frank, Aaron; Garcia-Caceres, Cristina; Navas, Carlos Rodriguez; Gordillo, Ruth; Neinast, Michael; Kalainayakan, Sarada P.; Li, Dan L.; Gao, Yuanqing; Yi, Chun-Xia; Hahner, Lisa; Palmer, Biff F.; Tschöp, Matthias H.; Clegg, Deborah J.

2014-01-01

High-fat diets (HFDs) lead to obesity and inflammation in the central nervous system (CNS). Estrogens and estrogen receptor alpha (ER alpha) protect premenopausal females from the metabolic complications of inflammation and obesity-related disease. Here, we demonstrate that hypothalamic PGC-1 alpha

Regulation of exercise-induced lipid metabolism in skeletal muscle

DEFF Research Database (Denmark)

Jordy, Andreas Børsting; Kiens, Bente

2014-01-01

Exercise increases the utilization of lipids in muscle. The sources of lipids are long-chain fatty acids taken up from the plasma and fatty acids released from stores of intramuscular triacylglycerol by the action of intramuscular lipases. In the present review, we focus on the role of fatty acid...... binding proteins, particularly fatty acid translocase/cluster of differentiation 36 (FAT/CD36), in the exercise- and contraction-induced increase in uptake of long-chain fatty acids in muscle. The FAT/CD36 translocates from intracellular depots to the surface membrane upon initiation of exercise/muscle...... triglyceride lipase in regulation of muscle lipolysis. Although the molecular regulation of the lipases in muscle is not understood, it is speculated that intramuscular lipolysis may be regulated in part by the availability of the plasma concentration of long-chain fatty acids....

Regulation of trehalose metabolism in Saccharomyces

International Nuclear Information System (INIS)

Panek, A.D.; Costa-Carvalho, V.L.A.; Ortiz, C.H.D.; Dellamora-Ortiz, G.M.; Paschoalin, V.M.F.; Panek, A.C.

1984-01-01

The regulation of trehalose metabolism in Saccharomyces is studied by construction of mutants with specific lesions, cloning of genes involved in the regulation of trehalose synthase and of trehalase, as well as, isolation and purification of enzymes from the various mutants constructed. (M.A.C.) [pt

Diacylglycerol-enriched structured lipids containing CLA and capric acid alter body fat mass and lipid metabolism in rats.

Science.gov (United States)

Kim, Hye-Jin; Lee, Ki-Teak; Lee, Mi-Kyung; Jeon, Seon-Min; Choi, Myung-Sook

2006-01-01

The present study compared the effect of corn oil, diacylglycerol (DG) oil, and DG-enriched structured lipids (SL-DG) produced from corn oil, capric and conjugated linoleic acid on adiposity in rats fed an AIN-76 diet (5% fat) for 6 weeks. The plasma and hepatic lipids, adipose tissue weight, and enzyme activities related to fatty acid metabolism were determined. The weights of the epididymal white adipose tissue (WAT), perirenal WAT, and interscapular WAT were significantly lower in the SL-DG group than in the DG group. Reduction of fat mass in the SL-DG group was related to suppressing fatty acid synthase activities and enhancing beta-oxidation activity in perirenal WAT. The plasma leptin was lower in the SL-DG group than in the DG group, plus a lower plasma TG level was accompanied by an increase in adipocyte LPL activity. Meanwhile the SL-DG supplement lowered the plasma and hepatic cholesterol level. In addition, the hepatic HMG-CoA reductase and ACAT activities were significantly lower in the SL-DG group than in the other groups. The DG-enriched SL used in this study was effective in enhancing triglyceride metabolism in adipose tissue, especially as regards reducing the abdominal fat mass and cholesterol metabolism in the liver. Copyright 2006 S. Karger AG, Basel.

Molecular fingerprint of high fat diet induced urinary bladder metabolic dysfunction in a rat model.

Directory of Open Access Journals (Sweden)

Andreas Oberbach

Full Text Available AIMS/HYPOTHESIS: Diabetic voiding dysfunction has been reported in epidemiological dimension of individuals with diabetes mellitus. Animal models might provide new insights into the molecular mechanisms of this dysfunction to facilitate early diagnosis and to identify new drug targets for therapeutic interventions. METHODS: Thirty male Sprague-Dawley rats received either chow or high-fat diet for eleven weeks. Proteomic alterations were comparatively monitored in both groups to discover a molecular fingerprinting of the urinary bladder remodelling/dysfunction. Results were validated by ELISA, Western blotting and immunohistology. RESULTS: In the proteome analysis 383 proteins were identified and canonical pathway analysis revealed a significant up-regulation of acute phase reaction, hypoxia, glycolysis, β-oxidation, and proteins related to mitochondrial dysfunction in high-fat diet rats. In contrast, calcium signalling, cytoskeletal proteins, calpain, 14-3-3η and eNOS signalling were down-regulated in this group. Interestingly, we found increased ubiquitin proteasome activity in the high-fat diet group that might explain the significant down-regulation of eNOS, 14-3-3η and calpain. CONCLUSIONS/INTERPRETATION: Thus, high-fat diet is sufficient to induce significant remodelling of the urinary bladder and alterations of the molecular fingerprint. Our findings give new insights into obesity related bladder dysfunction and identified proteins that may indicate novel pathophysiological mechanisms and therefore constitute new drug targets.

Long-Lasting Improvements in Liver Fat and Metabolism Despite Body Weight Regain After Dietary Weight Loss

OpenAIRE

Haufe, Sven; Haas, Verena; Utz, Wolfgang; Birkenfeld, Andreas L.; Jeran, Stephanie; Böhnke, Jana; Mähler, Anja; Luft, Friedrich C.; Schulz-Menger, Jeanette; Boschmann, Michael; Jordan, Jens; Engeli, Stefan

2013-01-01

OBJECTIVE Weight loss reduces abdominal and intrahepatic fat, thereby improving metabolic and cardiovascular risk. Yet, many patients regain weight after successful diet-induced weight loss. Long-term changes in abdominal and liver fat, along with liver test results and insulin resistance, are not known. RESEARCH DESIGN AND METHODS We analyzed 50 overweight to obese subjects (46 ± 9 years of age; BMI, 32.5 ± 3.3 kg/m2; women, 77%) who had participated in a 6-month hypocaloric diet and were ra...

Regulation of Specialized Metabolism by WRKY Transcription Factors

Science.gov (United States)

Schluttenhofer, Craig; Yuan, Ling

2015-01-01

WRKY transcription factors (TFs) are well known for regulating plant abiotic and biotic stress tolerance. However, much less is known about how WRKY TFs affect plant-specialized metabolism. Analysis of WRKY TFs regulating the production of specialized metabolites emphasizes the values of the family outside of traditionally accepted roles in stress tolerance. WRKYs with conserved roles across plant species seem to be essential in regulating specialized metabolism. Overall, the WRKY family plays an essential role in regulating the biosynthesis of important pharmaceutical, aromatherapy, biofuel, and industrial components, warranting considerable attention in the forthcoming years. PMID:25501946

MicroRNA Regulation of Brown Adipogenesis and Thermogenic Energy Expenditure

DEFF Research Database (Denmark)

Shamsi, Farnaz; Zhang, Hongbin; Tseng, Yu-Hua

2017-01-01

Obesity, diabetes, and associated metabolic diseases have become global epidemics. Obesity results from excess accumulation of white fat, while brown and its related beige fat function to dissipate energy as heat, thus counteracting obesity and its related metabolic disorders. Understanding...... attracted a great deal of research interests in exploring their roles in physiological and pathophysiological conditions. This review focuses on the recent advances of regulating brown adipogenesis and energy metabolism by miRNAs, aiming to delineate the regulatory principles of miRNAs on this unique aspect...... of energy homeostasis....

Red pitaya juice supplementation ameliorates energy balance homeostasis by modulating obesity-related genes in high-carbohydrate, high-fat diet-induced metabolic syndrome rats.

Science.gov (United States)

Ramli, Nurul Shazini; Ismail, Patimah; Rahmat, Asmah

2016-07-26

Red pitaya (Hylocereus polyrhizus) or known as buah naga merah in Malay belongs to the cactus family, Cactaceae. Red pitaya has been shown to give protection against liver damage and may reduce the stiffness of the heart. Besides, the beneficial effects of red pitaya against obesity have been reported; however, the mechanism of this protection is not clear. Therefore, in the present study, we have investigated the red pitaya-targeted genes in obesity using high-carbohydrate, high-fat diet-induced metabolic syndrome rat model. A total of four groups were tested: corn-starch (CS), corn-starch + red pitaya juice (CRP), high-carbohydrate, high-fat (HCHF) and high-carbohydrate, high-fat + red pitaya juice (HRP). The intervention with 5 % red pitaya juice was continued for 8 weeks after 8 weeks initiation of the diet. Retroperitoneal, epididymal and omental fat pads were collected and weighed. Plasma concentration of IL-6 and TNF-α were measured using commercial kits. Gene expression analysis was conducted using RNA extracted from liver samples. A total of eighty-four genes related to obesity were analyzed using PCR array. The rats fed HCHF-diet for 16 weeks increased body weight, developed excess abdominal fat deposition and down-regulated the expression level of IL-1α, IL-1r1, and Cntfr as compared to the control group. Supplementation of red pitaya juice for 8 weeks increased omental and epididymal fat but no change in retroperitoneal fat was observed. Red pitaya juice reversed the changes in energy balance homeostasis in liver tissues by regulation of the expression levels of Pomc and Insr. The increased protein expression levels of IL-6 and TNF-α in HCHF group and red pitaya treated rats confirmed the results of gene expression. Collectively, this study revealed the usefulness of this diet-induced rat model and the beneficial effects of red pitaya on energy balance homeostasis by modulating the anorectic, orexigenic and energy expenditure related

The role of leptin and other hormones related to bone metabolism and appetite-regulation as determinants of gain in body fat and fat-free mass in 8-11 year old children

DEFF Research Database (Denmark)

Dalskov, Stine-Mathilde; Ritz, Christian; Larnkjær, Anni

2015-01-01

Background: Regulation of body composition during childhood is complex. Numerous hormones are potentially involved. Leptin has been proposed to restrain weight gain, but results are inconsistent. Objectives: We examined if baseline fasting levels of ghrelin, adiponectin, leptin, insulin, insulin......-like growth factor I (IGF-1), osteocalcin and intact parathyroid hormone (iPTH) were associated with body composition cross-sectionally and longitudinally in 633 8-11-year-olds. Design: Data on hormones and body composition by Dual-energy X-ray absorptiometry from OPUS School Meal Study were used. We looked...... at baseline hormones as predictors of baseline fat mass index (FMI) or fat-free mass index (FFMI), and also subsequent changes (three and six months) in FMI or FFMI using models with hormones individually or combined. Results: Cross-sectionally, baseline leptin was positively associated with FMI in girls (0...

A high fat diet alters metabolic and bioenergetic function in the brain: A magnetic resonance spectroscopy study

OpenAIRE

Raider, Kayla; Ma, Delin; Harris, Janna L.; Fuentes, Isabella; Rogers, Robert S.; Wheatley, Joshua L.; Geiger, Paige C.; Yeh, Hung-Wen; Choi, In-Young; Brooks, William M.; Stanford, John A.

2016-01-01

Diet-induced obesity and associated metabolic effects can lead to neurological dysfunction and increase the risk of developing Alzheimer's disease (AD) and Parkinson's disease (PD). Despite these risks, the effects of a high-fat diet on the central nervous system are not well understood. To better understand the mechanisms underlying the effects of high fat consumption on brain regions affected by AD and PD, we used proton magnetic resonance spectroscopy (1H-MRS) to measure neurochemicals in ...

Maternal high-fat diet intensifies the metabolic response to stress in male rat offspring.

Science.gov (United States)

Karbaschi, Roxana; Zardooz, Homeira; Khodagholi, Fariba; Dargahi, Leila; Salimi, Mina; Rashidi, FatemehSadat

2017-01-01

The mother's consumption of high-fat food can affect glucose metabolism and the hypothalamic-pituitary-adrenal axis responsiveness in the offspring and potentially affect the metabolic responses to stress as well. This study examines the effect of maternal high-fat diet on the expression of pancreatic glucose transporter 2 and the secretion of insulin in response to stress in offspring. Female rats were randomly divided into normal and high-fat diet groups and were fed in accordance with their given diets from pre-pregnancy to the end of lactation. The offspring were divided into control (NC and HFC) and stress (NS and HFS) groups based on their mothers' diet and exposure to stress in adulthood. After the two-week stress induction period was over, an intraperitoneal glucose tolerance test (IPGTT) was performed and plasma glucose and insulin levels were assessed. The pancreas was then removed for measuring insulin secretion from the isolated islets as well as glucose transporter 2 mRNA expression and protein levels. According to the results obtained, plasma corticosterone concentrations increased significantly on days 1 and 14 of the stress induction period and were lower on the last day compared to on the first day. In both the NS and HFS groups, stress reduced plasma insulin concentration in the IPGTT without changing the plasma glucose concentration, suggesting an increased insulin sensitivity in the NS and HFS groups, although more markedly in the latter. Stress reduced insulin secretion (at high glucose concentrations) and increased glucose transporter 2 mRNA and protein expression, especially in the HFS group. Mothers' high-fat diet appears to intensify the stress response by changing the programming of the neuroendocrine system in the offspring.

Seasoning ingredients in a medium-fat diet regulate lipid metabolism in peripheral tissues via the hypothalamic-pituitary axis in growing rats.

Science.gov (United States)

Tanaka, Mitsuru; Yasuoka, Akihito; Yoshinuma, Haruka; Saito, Yoshikazu; Asakura, Tomiko; Tanabe, Soichi

2018-03-01

We fed rats noodle (N) -diet containing 30 wt.% instant noodle with a 26% fat-to-energy ratio for 30 days (N-group). Compared with rats that were fed the same amount of nutrients (C-group), the N-group showed lower liver triacylglycerol levels and higher fecal cholesterol levels. We then analyzed transcriptome of the hypothalamic-pituitary (HP), the liver and the white adipose tissue (WAT). Thyroid stimulating hormone (Tshb), and its partner, glycoprotein hormone genes were up-regulated in the HP of N-group. Sterol regulatory element binding transcription factors were activated in the liver of N-group, while an up-regulation of the angiogenic signal occurred in the WAT of N-group. N-group showed higher urine noradrenaline (NA) level suggesting that these tissue signals are regulated by NA and Tshb. The N-diet contains 0.326 wt.% glutamate, 0.00236 wt.% 6-shogaol and Maillard reaction products. Our results suggest that these ingredients may affect lipid homeostasis via the HP axis.

Transcriptional analysis of abdominal fat in genetically fat and lean chickens reveals adipokines, lipogenic genes and a link between hemostasis and leanness

Science.gov (United States)

2013-01-01

Background This descriptive study of the abdominal fat transcriptome takes advantage of two experimental lines of meat-type chickens (Gallus domesticus), which were selected over seven generations for a large difference in abdominal (visceral) fatness. At the age of selection (9 wk), the fat line (FL) and lean line (LL) chickens exhibit a 2.5-fold difference in abdominal fat weight, while their feed intake and body weight are similar. These unique avian models were originally created to unravel genetic and endocrine regulation of adiposity and lipogenesis in meat-type chickens. The Del-Mar 14K Chicken Integrated Systems microarray was used for a time-course analysis of gene expression in abdominal fat of FL and LL chickens during juvenile development (1–11 weeks of age). Results Microarray analysis of abdominal fat in FL and LL chickens revealed 131 differentially expressed (DE) genes (FDR≤0.05) as the main effect of genotype, 254 DE genes as an interaction of age and genotype and 3,195 DE genes (FDR≤0.01) as the main effect of age. The most notable discoveries in the abdominal fat transcriptome were higher expression of many genes involved in blood coagulation in the LL and up-regulation of numerous adipogenic and lipogenic genes in FL chickens. Many of these DE genes belong to pathways controlling the synthesis, metabolism and transport of lipids or endocrine signaling pathways activated by adipokines, retinoid and thyroid hormones. Conclusions The present study provides a dynamic view of differential gene transcription in abdominal fat of chickens genetically selected for fatness (FL) or leanness (LL). Remarkably, the LL chickens over-express a large number of hemostatic genes that could be involved in proteolytic processing of adipokines and endocrine factors, which contribute to their higher lipolysis and export of stored lipids. Some of these changes are already present at 1 week of age before the divergence in fatness. In contrast, the FL chickens have

The effects of a low-fat, plant-based dietary intervention on body weight, metabolism, and insulin sensitivity.

Science.gov (United States)

Barnard, Neal D; Scialli, Anthony R; Turner-McGrievy, Gabrielle; Lanou, Amy J; Glass, Jolie

2005-09-01

This study investigated the effect of a low-fat, plant-based diet on body weight, metabolism, and insulin sensitivity, while controlling for exercise in free-living individuals. In an outpatient setting, 64 overweight, postmenopausal women were randomly assigned to a low-fat, vegan diet or a control diet based on National Cholesterol Education Program guidelines, without energy intake limits, and were asked to maintain exercise unchanged. Dietary intake, body weight and composition, resting metabolic rate, thermic effect of food, and insulin sensitivity were measured at baseline and 14 weeks. Mean +/- standard deviation intervention-group body weight decreased 5.8 +/- 3.2 kg, compared with 3.8 +/- 2.8 kg in the control group (P = .012). In a regression model of predictors of weight change, including diet group and changes in energy intake, thermic effect of food, resting metabolic rate, and reported energy expenditure, significant effects were found for diet group (P effect of food (P vegan diet was associated with significant weight loss in overweight postmenopausal women, despite the absence of prescribed limits on portion size or energy intake.

Effects of Gliadin consumption on the Intestinal Microbiota and Metabolic Homeostasis in Mice Fed a High-fat Diet

DEFF Research Database (Denmark)

Zhang, Li; Andersen, Daniel; Roager, Henrik Munch

2017-01-01

of an obesogenic diet. Mice were fed either a defined high-fat diet (HFD) containing 4% gliadin (n = 20), or a gliadin-free, isocaloric HFD (n = 20) for 23 weeks. Combined analysis of several parameters including insulin resistance, histology of liver and adipose tissue, intestinal microbiota in three gut...... that gliadin disturbs the intestinal environment and affects metabolic homeostasis in obese mice, suggesting a detrimental effect of gluten intake in gluten-tolerant subjects consuming a high-fat diet.......Dietary gluten causes severe disorders like celiac disease in gluten-intolerant humans. However, currently understanding of its impact in tolerant individuals is limited. Our objective was to test whether gliadin, one of the detrimental parts of gluten, would impact the metabolic effects...

High Phenolics Rutgers Scarlet Lettuce Improves Glucose Metabolism in High Fat Diet-Induced Obese Mice

Science.gov (United States)

Cheng, Diana M.; Roopchand, Diana E.; Poulev, Alexander; Kuhn, Peter; Armas, Isabel; Johnson, William D.; Oren, Andrew; Ribnicky, David; Zelzion, Ehud; Bhattacharya, Debashish; Raskin, Ilya

2016-01-01

Scope The ability of high phenolic Rutgers Scarlet Lettuce (RSL) to attenuate metabolic syndrome and gut dysbiosis was studied in very high fat diet (VHFD)-fed mice. Phenolic absorption was assessed in vivo and in a gastrointestinal tract model. Methods and results Mice were fed VHFD, VHFD supplemented with RSL (RSL-VHFD) or store-purchased green lettuce (GL-VHFD), or low-fat diet (LFD) for 13 weeks. Compared to VHFD or GL-VHFD-fed groups, RSL-VHFD group showed significantly improved oral glucose tolerance (p<0.05). Comparison of VHFD, RSL-VHFD, and GL-VHFD groups revealed no significant differences with respect to insulin tolerance, hepatic lipids, body weight gain, fat mass, plasma glucose, triglycerides, free fatty acid, and lipopolysaccharide levels, as well as relative abundances of major bacterial phyla from 16S rDNA amplicon data sequences (from fecal and cecal samples). However, RSL and GL-supplementation increased abundance of several taxa involved in plant polysaccharide degradation/fermentation. RSL phenolics chlorogenic acid, quercetin-3-glucoside, and quercetin-malonyl-glucoside were bioaccessible in the TIM-1 digestion model, but had relatively low recovery. Conclusions RSL phenolics contributed to attenuation of postprandial hyperglycemia. Changes in gut microbiota were likely due to microbiota accessible carbohydrates in RSL and GL rather than RSL phenolics, which may be metabolized, absorbed, or degraded before reaching the colon. PMID:27529448

High-fat diet-induced adiposity, adipose inflammation, hepatic steatosis and hyperinsulinemia in outbred CD-1 mice.

Science.gov (United States)

Gao, Mingming; Ma, Yongjie; Liu, Dexi

2015-01-01

High-fat diet (HFD) has been applied to a variety of inbred mouse strains to induce obesity and obesity related metabolic complications. In this study, we determined HFD induced development of metabolic disorders on outbred female CD-1 mice in a time dependent manner. Compared to mice on regular chow, HFD-fed CD-1 mice gradually gained more fat mass and consequently exhibited accelerated body weight gain, which was associated with adipocyte hypertrophy and up-regulated expression of adipose inflammatory chemokines and cytokines such as Mcp-1 and Tnf-α. Increased fat accumulation in white adipose tissue subsequently led to ectopic fat deposition in brown adipose tissue, giving rise to whitening of brown adipose tissue without altering plasma level of triglyceride. Ectopic fat deposition was also observed in the liver, which was associated with elevated expression of key genes involved in hepatic lipid sequestration, including Ppar-γ2, Cd36 and Mgat1. Notably, adipose chronic inflammation and ectopic lipid deposition in the liver and brown fat were accompanied by glucose intolerance and insulin resistance, which was correlated with hyperinsulinemia and pancreatic islet hypertrophy. Collectively, these results demonstrate sequentially the events that HFD induces physiological changes leading to metabolic disorders in an outbred mouse model more closely resembling heterogeneity of the human population.

Roux-en-Y Gastric Bypass and Vertical Banded Gastroplasty Induce Long-Term Changes on the Human Gut Microbiome Contributing to Fat Mass Regulation

DEFF Research Database (Denmark)

Tremaroli, Valentina; Karlsson, Fredrik; Werling, Malin

2015-01-01

Bariatric surgery is currently the most effective procedure for the treatment of obesity. Given the role of the gut microbiota in regulating host metabolism and adiposity, we investigated the long-term effects of bariatric surgery on the microbiome of patients randomized to Roux-en-Y gastric bypass...... or vertical banded gastroplasty and matched for weight and fat mass loss. The two surgical procedures induced similar and durable changes on the gut microbiome that were not dependent on body mass index and resulted in altered levels of fecal and circulating metabolites compared with obese controls....... By colonizing germ-free mice with stools from the patients, we demonstrated that the surgically altered microbiota promoted reduced fat deposition in recipient mice. These mice also had a lower respiratory quotient, indicating decreased utilization of carbohydrates as fuel. Our results suggest that the gut...

Bile Acid Metabolism in Liver Pathobiology

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Chiang, John Y. L.; Ferrell, Jessica M.

2018-01-01

Bile acids facilitate intestinal nutrient absorption and biliary cholesterol secretion to maintain bile acid homeostasis, which is essential for protecting liver and other tissues and cells from cholesterol and bile acid toxicity. Bile acid metabolism is tightly regulated by bile acid synthesis in the liver and bile acid biotransformation in the intestine. Bile acids are endogenous ligands that activate a complex network of nuclear receptor farnesoid X receptor and membrane G protein-coupled bile acid receptor-1 to regulate hepatic lipid and glucose metabolic homeostasis and energy metabolism. The gut-to-liver axis plays a critical role in the regulation of enterohepatic circulation of bile acids, bile acid pool size, and bile acid composition. Bile acids control gut bacteria overgrowth, and gut bacteria metabolize bile acids to regulate host metabolism. Alteration of bile acid metabolism by high-fat diets, sleep disruption, alcohol, and drugs reshapes gut microbiome and causes dysbiosis, obesity, and metabolic disorders. Gender differences in bile acid metabolism, FXR signaling, and gut microbiota have been linked to higher prevalence of fatty liver disease and hepatocellular carcinoma in males. Alteration of bile acid homeostasis contributes to cholestatic liver diseases, inflammatory diseases in the digestive system, obesity, and diabetes. Bile acid-activated receptors are potential therapeutic targets for developing drugs to treat metabolic disorders. PMID:29325602

Regulation of low-density lipoprotein receptor and 3-hydroxy-3-methylglutaryl coenzyme A reductase expression by Zingiber officinale in the liver of high-fat diet-fed rats.

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Nammi, Srinivas; Kim, Moon S; Gavande, Navnath S; Li, George Q; Roufogalis, Basil D

2010-05-01

Zingiber officinale has been used to control lipid disorders and reported to possess remarkable cholesterol-lowering activity in experimental hyperlipidaemia. In the present study, the effect of a characterized and standardized extract of Zingiber officinale on the hepatic lipid levels as well as on the hepatic mRNA and protein expression of low-density lipoprotein (LDL) receptor and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase was investigated in a high-fat diet-fed rat model. Rats were treated with an ethanol extract of Zingiber officinale (400 mg/kg) extract along with a high-fat diet for 6 weeks. The extract of Zingiber officinale significantly decreased hepatic triglyceride and tended to decrease hepatic cholesterol levels when administered over 6 weeks to the rats fed a high-fat diet. We found that in parallel, the extract up-regulated both LDL receptor mRNA and protein level and down-regulated HMG-CoA reductase protein expression in the liver of these rats. The metabolic control of body lipid homeostasis is in part due to enhanced cholesterol biosynthesis and reduced expression of LDL receptor sites following long-term consumption of high-fat diets. The present results show restoration of transcriptional and post-transcriptional changes in low-density lipoprotein and HMG CoA reductase by Zingiber officinale administration with a high-fat diet and provide a rational explanation for the effect of ginger in the treatment of hyperlipidaemia.

Mouse breast cancer model-dependent changes in metabolic syndrome-associated phenotypes caused by maternal dioxin exposure and dietary fat

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La Merrill, Michele; Baston, David S.; Denison, Michael S.; Birnbaum, Linda S.; Pomp, Daniel; Threadgill, David W.

2009-01-01

Diets high in fat are associated with increased susceptibility to obesity and metabolic syndrome. Increased adipose tissue that is caused by high-fat diets (HFD) results in altered storage of lipophilic toxicants like 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), which may further increase susceptibility to metabolic syndrome. Because both TCDD and HFD are associated with increased breast cancer risk, we examined their effects on metabolic syndrome-associated phenotypes in three mouse models of breast cancer: 7,12-dimethylbenz[a]anthracene (DMBA), Tg(MMTV-Neu)202Mul/J (HER2), and TgN(MMTV-PyMT)634Mul/J (PyMT), all on an FVB/N genetic background. Pregnant mice dosed with 1 μg/kg of TCDD or vehicle on gestational day 12.5 were placed on a HFD or low-fat diet (LFD) at parturition. Body weights, percent body fat, and fasting blood glucose were measured longitudinally, and triglycerides were measured at study termination. On HFD, all cancer models reached the pubertal growth spurt ahead of FVB controls. Among mice fed HFD, the HER2 model had a greater increase in body weight and adipose tissue from puberty through adulthood compared with the PyMT and DMBA models. However, the DMBA model consistently had higher fasting blood glucose levels than the PyMT and HER2 models. TCDD only impacted serum triglycerides in the PyMT model maintained on HFD. Because the estrogenic activity of the HFD was three times lower than that of the LFD, differential dietary estrogenic activities did not drive the observed phenotypic differences. Rather, the HFD-dependent changes were cancer model dependent. These results show that cancer models can have differential effects on metabolic syndrome-associated phenotypes even before cancers arise. PMID:18840765

Basis of aggravated hepatic lipid metabolism by chronic stress in high-fat diet-fed rat.

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Han, Ying; Lin, Min; Wang, Xiaobin; Guo, Keke; Wang, Shanshan; Sun, Mengfei; Wang, Jiao; Han, Xiaoyu; Fu, Ting; Hu, Yang; Fu, Jihua

2015-03-01

Our previous study has demonstrated that long-term stress, known as chronic stress (CS), can aggravate nonalcoholic fatty liver disease in high-fat diet (HFD)-fed rat. In this study, we tried to figure out which lipid metabolic pathways were impacted by CS in the HFD-fed rat. Male Sprague-Dawley rats (6 weeks of age, n = 8 per group) were fed with either standard diet or HFD with or without CS exposure for 8 weeks. Hepatic lipidosis, biochemical, hormonal, and lipid profile markers in serum and liver, and enzymes involved in de novo lipogenesis (DNL) of fatty acids (FAs) and cholesterol, β-oxidation, FAs uptake, triglycerides synthesis, and very low-density lipoprotein (VLDL) assembly in the liver were detected. CS exposure reduced hepatic lipidosis but further elevated hepatic VLDL content with aggravated dyslipidemia in the HFD-fed rats. There was a synergism between CS and HFD on VLDL production and dyslipidemia. PCR and western blot assays showed that CS exposure significantly promoted hepatic VLDL assembly in rats, especially in the HFD-fed rats, while it had little impact on DNL, β-oxidation, FAs uptake, and triglycerides synthesis in the HFD-fed rats. This phenomenon was in accordance with elevated serum glucocorticoid level. The critical influence of CS exposure on hepatic lipid metabolism in the HFD-fed rats is VLDL assembly which might be regulated by glucocorticoid.

Green tea polyphenols alter lipid metabolism in the livers of broiler chickens through increased phosphorylation of AMP-activated protein kinase.

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Jinbao Huang

Full Text Available Our previous results showed that green tea polyphenols (GTPs significantly altered the expression of lipid-metabolizing genes in the liver of chickens. However, the underlying mechanism was not elucidated. In this study, we further characterized how GTPs influence AMP-activated protein kinase (AMPK in the regulation of hepatic fat metabolism. Thirty-six male chickens were fed GTPs at a daily dose of 0, 80 or 160 mg/kg of body weight for 4 weeks. The results demonstrated that oral administration of GTPs significantly reduced hepatic lipid content and abdominal fat mass, enhanced the phosphorylation levels of AMPKα and ACACA, and altered the mRNA levels and enzymatic activities of lipid-metabolizing enzymes in the liver. These results suggested that the activation of AMPK is a potential mechanism by which GTPs regulate hepatic lipid metabolism in such a way that lipid synthesis is reduced and fat oxidation is stimulated.

Polychlorinated Biphenyl-Xenobiotic Nuclear Receptor Interactions Regulate Energy Metabolism, Behavior, and Inflammation in Non-alcoholic-Steatohepatitis.

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Wahlang, Banrida; Prough, Russell A; Falkner, K Cameron; Hardesty, Josiah E; Song, Ming; Clair, Heather B; Clark, Barbara J; States, J Christopher; Arteel, Gavin E; Cave, Matthew C

2016-02-01

Polychlorinated biphenyls (PCBs) are environmental pollutants associated with non-alcoholic-steatohepatitis (NASH), diabetes, and obesity. We previously demonstrated that the PCB mixture, Aroclor 1260, induced steatohepatitis and activated nuclear receptors in a diet-induced obesity mouse model. This study aims to evaluate PCB interactions with the pregnane-xenobiotic receptor (Pxr: Nr1i2) and constitutive androstane receptor (Car: Nr1i3) in NASH. Wild type C57Bl/6 (WT), Pxr(-/-) and Car(-/-) mice were fed the high fat diet (42% milk fat) and exposed to a single dose of Aroclor 1260 (20 mg/kg) in this 12-week study. Metabolic phenotyping and analysis of serum, liver, and adipose was performed. Steatohepatitis was pathologically similar in all Aroclor-exposed groups, while Pxr(-/-) mice displayed higher basal pro-inflammatory cytokine levels. Pxr repressed Car expression as evident by increased basal Car/Cyp2b10 expression in Pxr(-/-) mice. Both Pxr(-/-) and Car(-/-) mice showed decreased basal respiratory exchange rate (RER) consistent with preferential lipid metabolism. Aroclor increased RER and carbohydrate metabolism, associated with increased light cycle activity in both knockouts, and decreased food consumption in the Car(-/-) mice. Aroclor exposure improved insulin sensitivity in WT mice but not glucose tolerance. The Aroclor-exposed, Pxr(-/-) mice displayed increased gluconeogenic gene expression. Lipid-oxidative gene expression was higher in WT and Pxr(-/-) mice although RER was not changed, suggesting PCB-mediated mitochondrial dysfunction. Therefore, Pxr and Car regulated inflammation, behavior, and energy metabolism in PCB-mediated NASH. Future studies should address the 'off-target' effects of PCBs in steatohepatitis. Published by Oxford University Press on behalf of the Society of Toxicology 2015. This work is written by US Government employees and is in the public domain in the US.

Differential metabolic effects of constant moderate versus high intensity interval training in high-fat fed mice: possible role of muscle adiponectin.

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Martinez-Huenchullan, Sergio F; Maharjan, Babu Raja; Williams, Paul F; Tam, Charmaine S; Mclennan, Susan V; Twigg, Stephen M

2018-02-01

Exercise regimens may have differing effects in the presence of obesity. In addition to being fat derived, adiponectin has recently been described as a myokine that regulates insulin sensitivity, which may link to exercise-related metabolic benefits in obesity. Whether skeletal muscle adiponectin varies in different exercise modalities is unclear. This study investigated the comparative effects of 10 weeks of endurance constant-moderate intensity exercise (END) with high intensity interval training (HIIT), on metabolic outcomes, including muscle adiponectin in a mouse model of diet-induced obesity. Ten-week-old male C57BL/6 mice were fed a high-fat diet (HFD) (45% FAT) or standard CHOW diet ab libitum and underwent one of three training regimes: (1) no exercise, (2) END, or (3) HIIT (8 bouts of 2.5 min with eight periods of rest of 2.5 min) for 10 weeks (3 × 40 min sessions/week). Chow-fed mice acted as controls. Compared with HFD alone, both training programs similarly protected against body weight gain (HFD = 45 ± 2; END = 37 ± 2; HIIT = 36 ± 2 g), preserved lean/fat tissue mass ratio (HFD = 0.64 ± 0.09; END = 0.34 ± 0.13; HIIT = 0.33 ± 0.13), and improved blood glucose excursion during an insulin tolerance test (HFD = 411 ± 54; END = 350 ± 57; HIIT = 320 ± 66 arbitrary units [AU]). Alterations in fasting glycemia, insulinemia, and AST/ALT ratios were prevented only by END. END, but not HIIT increased skeletal muscle adiponectin mRNA (14-fold; P HIIT induced a milder increase (2.4-fold). Compared with HFD, neither END nor HIIT altered circulating low (LMW) or high (HMW) molecular weight adiponectin forms. Furthermore, only END prevented the HFD downregulation of PGC1α (P < 0.05) mRNA levels downstream of muscle adiponectin. These data show that different training programs affect muscle adiponectin to differing degrees. Together these results suggest that END is a more effective regimen to prevent HFD

[THE INCONSISTENCIES OF REGULATION OF METABOLISM IN PHYLOGENESIS AT THREE LEVELS OF "RELATIVE BIOLOGICAL PERFECTION": ETIOLOGY OF METABOLIC PANDEMICS].

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Titov, V N

2015-11-01

The regulation of metabolism in vivo can be comprehended by considering stages of becoming inphylogenesis of humoral, hormonal, vegetative regulators separately: at the level of cells; in paracrin-regulated cenosises of cells; organs and systems under open blood circulation and closed system of blood flow. The levels of regulations formed at different stages of phylogenesis. Their completion occurred at achievement of "relative biological perfection". Only this way need of cells in functional, structural interaction and forming of multicellular developed. The development of organs and systems of organs also completed at the level of "relative biological perfection". From the same level the third stage of becoming of regulation of metabolism at the level of organism started. When three conditions of "relative biological perfection" achieved consequently at level in vivo are considered in species Homo sapiens using system approach it is detected that "relative biological perfection" in vivo is accompanied by different inconsistencies of regulation of metabolism. They are etiologic factors of "metabolic pandemics ". The inconsistencies (etiological factors) are consider as exemplified by local (at the level of paracrin-regulated cenosises of cells) and system (at the level of organism) regulation of biological reaction metabolism-microcirculation that results in dysfunction of target organs and development of pathogenesis of essential metabolic arterial hypertension. The article describes phylogenetic difference between visceral fatty cells and adpocytes, regulation of metabolism by phylogenetically late insulin, reaction of albumin at increasing of content of unesterified fatty acids in blood plasma, difference of function of resident macrophage and monocytes-macrophages in pathogenesis of atherosclerosis, metabolic syndrome, insulin resistance, obesity, under diabetes mellitus and essential metabolic arterial hypertension.

Fibroblast Growth Factor Signaling in Metabolic Regulation.

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Nies, Vera J M; Sancar, Gencer; Liu, Weilin; van Zutphen, Tim; Struik, Dicky; Yu, Ruth T; Atkins, Annette R; Evans, Ronald M; Jonker, Johan W; Downes, Michael Robert

2015-01-01

The prevalence of obesity is a growing health problem. Obesity is strongly associated with several comorbidities, such as non-alcoholic fatty liver disease, certain cancers, insulin resistance, and type 2 diabetes, which all reduce life expectancy and life quality. Several drugs have been put forward in order to treat these diseases, but many of them have detrimental side effects. The unexpected role of the family of fibroblast growth factors in the regulation of energy metabolism provides new approaches to the treatment of metabolic diseases and offers a valuable tool to gain more insight into metabolic regulation. The known beneficial effects of FGF19 and FGF21 on metabolism, together with recently discovered similar effects of FGF1 suggest that FGFs and their derivatives carry great potential as novel therapeutics to treat metabolic conditions. To facilitate the development of new therapies with improved targeting and minimal side effects, a better understanding of the molecular mechanism of action of FGFs is needed. In this review, we will discuss what is currently known about the physiological roles of FGF signaling in tissues important for metabolic homeostasis. In addition, we will discuss current concepts regarding their pharmacological properties and effector tissues in the context of metabolic disease. Also, the recent progress in the development of FGF variants will be reviewed. Our goal is to provide a comprehensive overview of the current concepts and consensuses regarding FGF signaling in metabolic health and disease and to provide starting points for the development of FGF-based therapies against metabolic conditions.

Fibroblast growth factor signaling in metabolic regulation

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Vera eNies

2016-01-01

Full Text Available The prevalence of obesity is a growing health problem. Obesity is strongly associated with several comorbidities, such as non-alcoholic fatty liver disease, certain cancers, insulin resistance and type 2 diabetes, which all reduce life expectancy and life quality. Several drugs have been put forward in order to treat these diseases, but many of them have detrimental side effects. The unexpected role of the family of fibroblast growth factors in the regulation of energy metabolism provides new approaches to the treatment of metabolic diseases, and offers a valuable tool to gain more insight into metabolic regulation. The known beneficial effects of FGF19 and FGF21 on metabolism, together with recently discovered similar effects of FGF1 suggest that FGFs and their derivatives carry great potential as novel therapeutics to treat metabolic conditions. To facilitate the development of new therapies with improved targeting and minimal side effects, a better understanding of the molecular mechanism of action of FGFs is needed.In this review we will discuss what is currently known about the physiological roles of FGF signaling in tissues important for metabolic homeostasis. In addition, we will discuss current concepts regarding their pharmacological properties and effector tissues in the context of metabolic disease. Also the recent progress in the development of FGF variants will be reviewed. Our goal is to provide a comprehensive overview of the current concepts and consensuses regarding FGF signaling in metabolic health and disease, and to provide starting points for the development of FGF-based therapies against metabolic conditions.

Relationships between rodent white adipose fat pads and human white adipose fat depots

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Daniella E. Chusyd

2016-04-01

Full Text Available The objective of this review was to compare and contrast the physiological and metabolic profiles of rodent white adipose fat pads with white adipose fat depots in humans. Human fat distribution and its metabolic consequences have received extensive attention, but much of what has been tested in translational research has relied heavily on rodents. Unfortunately, the validity of using rodent fat pads as a model of human adiposity has received less attention. There is a surprisingly lack of studies demonstrating an analogous relationship between rodent and human adiposity on obesity-related comorbidities. Therefore, we aimed to compare known similarities and disparities in terms of white adipose tissue development and distribution, sexual dimorphism, weight loss, adipokine secretion, and aging. While the literature supports the notion that many similarities exist between rodents and humans, notable differences emerge related to fat deposition and function of white adipose tissue. Thus, further research is warranted to more carefully define the strengths and limitations of rodent white adipose tissue as a model for humans, with a particular emphasis on comparable fat depots, such as mesenteric fat.

Differential Effects of High-Carbohydrate and High-Fat Diet Composition on Metabolic Control and Insulin Resistance in Normal Rats

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Ble-Castillo, Jorge L.; Aparicio-Trapala, María A.; Juárez-Rojop, Isela E.; Torres-Lopez, Jorge E.; Mendez, Jose D.; Aguilar-Mariscal, Hidemi; Olvera-Hernández, Viridiana; Palma-Cordova, Leydi C.; Diaz-Zagoya, Juan C.

2012-01-01

The macronutrient component of diets is critical for metabolic control and insulin action. The aim of this study was to compare the effects of high fat diets (HFDs) vs. high carbohydrate diets (HCDs) on metabolic control and insulin resistance in Wistar rats. Thirty animals divided into five groups (n = 6) were fed: (1) Control diet (CD); (2) High-saturated fat diet (HSFD); (3) High-unsaturated fat diet (HUFD); (4) High-digestible starch diet, (HDSD); and (5) High-resistant starch diet (HRSD) during eight weeks. HFDs and HCDs reduced weight gain in comparison with CD, however no statistical significance was reached. Calorie intake was similar in both HFDs and CD, but rats receiving HCDs showed higher calorie consumption than other groups, (p < 0.01). HRSD showed the lowest levels of serum and hepatic lipids. The HUFD induced the lowest fasting glycemia levels and HOMA-IR values. The HDSD group exhibited the highest insulin resistance and hepatic cholesterol content. In conclusion, HUFD exhibited the most beneficial effects on glycemic control meanwhile HRSD induced the highest reduction on lipid content and did not modify insulin sensitivity. In both groups, HFDs and HCDs, the diet constituents were more important factors than caloric intake for metabolic disturbance and insulin resistance. PMID:22754464

Dietary pattern associated with selenoprotein P and MRI-derived body fat volumes, liver signal intensity, and metabolic disorders.

Science.gov (United States)

di Giuseppe, Romina; Plachta-Danielzik, Sandra; Koch, Manja; Nöthlings, Ute; Schlesinger, Sabrina; Borggrefe, Jan; Both, Marcus; Müller, Hans-Peter; Kassubek, Jan; Jacobs, Gunnar; Lieb, Wolfgang

2018-02-14

The association of complex dietary patterns with circulating selenoprotein P (SELENOP) levels in humans is unknown. In a general population sample, we aimed to identify a dietary pattern explaining inter-individual variation in circulating SELENOP concentrations and to study this pattern in relation to prevalent diabetes, metabolic syndrome (MetS), MRI-determined total volumes of visceral (VAT) and subcutaneous (SAT) abdominal adipose tissue, and liver signal intensity/fatty liver disease. In this cross-sectional study, serum SELENOP levels were measured in 853 individuals. In a subsample of 553 participants, whole-body MRI was performed to assess body fat distribution and liver fat. Dietary intake was assessed by a self-administered food frequency questionnaire and the dietary pattern identified using reduced-rank regression (RRR). Multivariable linear and logistic regressions were used to investigate associations between dietary pattern score and metabolic traits. Characterized by high intake of fruit, vegetables and antioxidant beverages, the RRR-derived dietary pattern displayed inverse associations with VAT, SAT, MetS, and prevalent diabetes in multivariable-adjusted restricted cubic splines. Each unit increase in dietary pattern score was associated with 31% higher SELENOP levels, 12% lower VAT (95% CI: - 19%; - 5%), 13% (95% CI: - 20%; - 6%) lower SAT values and 46% (95% CI: 27%; 60%) and 53% (95% CI: 22%; 72%) lower odds of having MetS or diabetes, respectively. No meaningful relations were observed between the dietary pattern and liver traits. Our observations propose diet-related regulation in SELENOP levels and that the identified dietary pattern is inversely related to VAT, SAT, MetS, and prevalent diabetes.

The regulatory effects of fish oil and chitosan on hepatic lipogenic signals in high-fat diet-induced obese rats.

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Chiu, Chen-Yuan; Chang, Tien-Chia; Liu, Shing-Hwa; Chiang, Meng-Tsan

2017-10-01

The present study investigated the regulatory effects of fish oil and chitosan on the signals of hepatic lipid metabolism and the postulated mechanism in high-fat diet-induced obese rats. Diet supplementation of chitosan and fish oil efficiently suppressed the increased weights in body and livers of high-fat diet-fed rats. Supplementation of chitosan and fish oil significantly decreased the activities of hepatic lipid biosynthesis-related enzymes and efficiently regulated plasma lipoprotein homeostasis. Both chitosan and fish oil significantly ameliorated the alterations in the protein expressions of hepatic lipogenic transcription factors (LXRα and PPARα), and could also significantly regulate the downstream hepatic lipogenic genes (FAS, HMGCR, CYP7A1, FATP, FABP, AOX, and ABCA) expressions in high-fat diet-fed rats. These results suggest that both fish oil and chitosan exerts downregulative effects on hepatic lipid metabolism in high-fat diet-induced obese rats via the LXRα inhibition and PPARα activation, which further affect the expressions of hepatic lipogenesis-associated genes. Copyright © 2017. Published by Elsevier B.V.

Physiological and Pathogenic Roles of Prolyl Isomerase Pin1 in Metabolic Regulations via Multiple Signal Transduction Pathway Modulations

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Yusuke Nakatsu

2016-09-01

Full Text Available Prolyl isomerases are divided into three groups, the FKBP family, Cyclophilin and the Parvulin family (Pin1 and Par14. Among these isomerases, Pin1 is a unique prolyl isomerase binding to the motif including pSer/pThr-Pro that is phosphorylated by kinases. Once bound, Pin1 modulates the enzymatic activity, protein stability or subcellular localization of target proteins by changing the cis- and trans-formations of proline. Several studies have examined the roles of Pin1 in the pathogenesis of cancers and Alzheimer’s disease. On the other hand, recent studies have newly demonstrated Pin1 to be involved in regulating glucose and lipid metabolism. Interestingly, while Pin1 expression is markedly increased by high-fat diet feeding, Pin1 KO mice are resistant to diet-induced obesity, non-alcoholic steatohepatitis and diabetic vascular dysfunction. These phenomena result from the binding of Pin1 to several key factors regulating metabolic functions, which include insulin receptor substrate-1, AMPK, Crtc2 and NF-κB p65. In this review, we focus on recent advances in elucidating the physiological roles of Pin1 as well as the pathogenesis of disorders involving this isomerase, from the viewpoint of the relationships between signal transductions and metabolic functions.

Metabolic and behavioral responses to high-fat feeding in mice selectively bred for high wheel-running activity

NARCIS (Netherlands)

Vaanholt, L. M.; Jonas, I.; Doornbos, M.; Schubert, K. A.; Nyakas, C.; Garland, T.; Visser, G. H.; van Dijk, G.; Garland Jr., T.

2008-01-01

Objective: Increased dietary fat intake is a precipitating factor for the development of obesity and associated metabolic disturbances. Physically active individuals generally have a reduced risk of developing these unhealthy states, but the underlying mechanisms are poorly understood. In the

Browning and graying: novel transcriptional regulators of brown and beige fat tissues and aging

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Elisabetta eMueller

2016-03-01

Full Text Available Obesity represents a major risk factor for the development of a number of metabolic disorders, including cardiovascular disease and type 2 diabetes. Since the discovery that brown and beige fat cells exist in adult humans and contribute to energy expenditure, increasing interest has been devoted to the understanding of the molecular switches turning on calorie utilization. It has been reported that the ability of thermogenic tissues to burn energy declines during aging, possibly contributing to the development of metabolic dysfunction late in life. This review will focus on the recently identified transcriptional modulators of brown and beige cells and will discuss the potential impact of some of these thermogenic factors on age-associated metabolic disorders.

The Resin from Protium heptaphyllum Prevents High-Fat Diet-Induced Obesity in Mice: Scientific Evidence and Potential Mechanisms

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Karine Maria Martins Bezerra Carvalho

2015-01-01

Full Text Available Herbal compounds rich in triterpenes are well known to regulate glucose and lipid metabolism and to have beneficial effects on metabolic disorders. The present study investigated the antiobesity properties of resin from Protium heptaphyllum (RPH and the possible mechanisms in mice fed a high-fat diet (HFD for 15 weeks. Mice treated with RPH showed decreases in body weight, net energy intake, abdominal fat accumulation, plasma glucose, amylase, lipase, triglycerides, and total cholesterol relative to their respective controls, which were RPH unfed. Additionally, RPH treatment, while significantly elevating the plasma level of ghrelin hormone, decreased the levels of insulin, leptin, and resistin. Besides, HFD-induced increases in plasma levels of proinflammatory mediators TNF-α, IL-6, and MCP-1 were significantly lowered by RPH. Furthermore, in vitro studies revealed that RPH could significantly inhibit the lipid accumulation in 3T3-L1 adipocytes (measured by Oil-Red O staining at concentrations up to 50 μg/mL. These findings suggest that the antiobese potential of RPH is largely due to its modulatory effects on various hormonal and enzymatic secretions related to fat and carbohydrate metabolism and to the regulation of obesity-associated inflammation.

Metabolic control by S6 kinases depends on dietary lipids.

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Tamara R Castañeda

Full Text Available Targeted deletion of S6 kinase (S6K 1 in mice leads to higher energy expenditure and improved glucose metabolism. However, the molecular mechanisms controlling these effects remain to be fully elucidated. Here, we analyze the potential role of dietary lipids in regulating the mTORC1/S6K system. Analysis of S6K phosphorylation in vivo and in vitro showed that dietary lipids activate S6K, and this effect is not dependent upon amino acids. Comparison of male mice lacking S6K1 and 2 (S6K-dko with wt controls showed that S6K-dko mice are protected against obesity and glucose intolerance induced by a high-fat diet. S6K-dko mice fed a high-fat diet had increased energy expenditure, improved glucose tolerance, lower fat mass gain, and changes in markers of lipid metabolism. Importantly, however, these metabolic phenotypes were dependent upon dietary lipids, with no such effects observed in S6K-dko mice fed a fat-free diet. These changes appear to be mediated via modulation of cellular metabolism in skeletal muscle, as shown by the expression of genes involved in energy metabolism. Taken together, our results suggest that the metabolic functions of S6K in vivo play a key role as a molecular interface connecting dietary lipids to the endogenous control of energy metabolism.

Comparative nontargeted profiling of metabolic changes in tissues and biofluids in high-fat diet-fed Ossabaw pig

DEFF Research Database (Denmark)

Hanhineva, Kati; Barri, Thaer; Kolehmainen, Marjukka

2013-01-01

to reveal metabolite groups for generating new hypotheses of obesity-related metabolic disturbances produced in an animal model. A large spectrum of metabolites in the semi-polar region, including small water soluble molecules like betaine and dihydroxyindole, and a wide range of bile acids as well...... as various lipid species were detected. The high fat diet influenced metabolic homeostasis of Ossabaw pigs, especially the lipid metabolome, throughout all the analyzed sample types, including plasma, urine, bile, liver, pancreas, brain cortex, intestinal jejunum and proximal colon. However, even dramatic...... and lipids, thus pointing to the pathways of metabolism affected by the dietary treatment....

Regulation of PCP by the Fat signaling pathway

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Matis, Maja; Axelrod, Jeffrey D.

2013-01-01

Planar cell polarity (PCP) in epithelia, orthogonal to the apical–basal axis, is essential for numerous developmental events and physiological functions. Drosophila model systems have been at the forefront of studies revealing insights into mechanisms regulating PCP and have revealed distinct signaling modules. One of these, involving the atypical cadherins Fat and Dachsous and the ectokinase Four-jointed, appears to link the direction of cell polarization to the tissue axes. We discuss models for the function of this signaling module as well as several unanswered questions that may guide future investigations. PMID:24142873

Dietary fat and corticosterone levels are contributing factors to meal anticipation.

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Namvar, Sara; Gyte, Amy; Denn, Mark; Leighton, Brendan; Piggins, Hugh D

2016-04-15

Daily restricted access to food leads to the development of food anticipatory activity and metabolism, which depends upon an as yet unidentified food-entrainable oscillator(s). A premeal anticipatory peak in circulating hormones, including corticosterone is also elicited by daily restricted feeding. High-fat feeding is associated with elevated levels of corticosterone with disrupted circadian rhythms and a failure to develop robust meal anticipation. It is not clear whether the disrupted corticosterone rhythm, resulting from high-fat feeding contributes to attenuated meal anticipation in high-fat fed rats. Our aim was to better characterize meal anticipation in rats fed a low- or high-fat diet, and to better understand the role of corticosterone in this process. To this end, we utilized behavioral observations, hypothalamic c-Fos expression, and indirect calorimetry to assess meal entrainment. We also used the glucocorticoid receptor antagonist, RU486, to dissect out the role of corticosterone in meal anticipation in rats given daily access to a meal with different fat content. Restricted access to a low-fat diet led to robust meal anticipation, as well as entrainment of hypothalamic c-Fos expression, metabolism, and circulating corticosterone. These measures were significantly attenuated in response to a high-fat diet, and animals on this diet exhibited a postanticipatory rise in corticosterone. Interestingly, antagonism of glucocorticoid activity using RU486 attenuated meal anticipation in low-fat fed rats, but promoted meal anticipation in high-fat-fed rats. These findings suggest an important role for corticosterone in the regulation of meal anticipation in a manner dependent upon dietary fat content. Copyright © 2016 the American Physiological Society.

Correlation of Visceral Fat Area with Metabolic Risk Factors in Romanian Patients: A Cross-Sectional Study

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Hâncu Anca

2015-12-01

Full Text Available Background and Aims: The aim of the present study was to investigate the relationship between visceral fat area (VFA, estimated by bioimpedance, and cardiovascular risk factors independent of BMI and waist circumference in a cohort of Romanian patients. Material and Methods: This was a cross-sectional study, in which were collected data from 751 patients ≥18 years of age from Cluj-Napoca. Anthropometric, biochemistry, body composition and medical history parameters were recorded from patients’ files. Results: Compared with the participants with VFA <100 cm2, those with VFA ≥100 cm2 had significantly worse levels of the laboratory parameters describing the glycemic metabolism, lipid metabolism and liver functions (p <0.05 for all. A higher percentage of participants with VFA ≥100 cm2 had diabetes, obesity, hypertension, hypertriglyceridemia and hypo-HDL cholesterolemia (p <0.05 for all. VFA was correlated with systolic and diastolic blood pressure, total and LDL-cholesterol levels, triglycerides, ALT, previous diagnosis of diabetes, hypertriglyceridemia and hypo-HDL cholesterolemia independent of BMI and waist circumference. Conclusions: Among this cohort of Romanian adults, an increasing level of visceral adiposity was correlated with worse lipid and glucose metabolism parameters as well as with increased levels of ALT, which probably reflects liver fat deposition.

Acetic acid activates the AMP-activated protein kinase signaling pathway to regulate lipid metabolism in bovine hepatocytes.

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Xinwei Li

Full Text Available The effect of acetic acid on hepatic lipid metabolism in ruminants differs significantly from that in monogastric animals. Therefore, the aim of this study was to investigate the regulation mechanism of acetic acid on the hepatic lipid metabolism in dairy cows. The AMP-activated protein kinase (AMPK signaling pathway plays a key role in regulating hepatic lipid metabolism. In vitro, bovine hepatocytes were cultured and treated with different concentrations of sodium acetate (neutralized acetic acid and BML-275 (an AMPKα inhibitor. Acetic acid consumed a large amount of ATP, resulting in an increase in AMPKα phosphorylation. The increase in AMPKα phosphorylation increased the expression and transcriptional activity of peroxisome proliferator-activated receptor α, which upregulated the expression of lipid oxidation genes, thereby increasing lipid oxidation in bovine hepatocytes. Furthermore, elevated AMPKα phosphorylation reduced the expression and transcriptional activity of the sterol regulatory element-binding protein 1c and the carbohydrate responsive element-binding protein, which reduced the expression of lipogenic genes, thereby decreasing lipid biosynthesis in bovine hepatocytes. In addition, activated AMPKα inhibited the activity of acetyl-CoA carboxylase. Consequently, the triglyceride content in the acetate-treated hepatocytes was significantly decreased. These results indicate that acetic acid activates the AMPKα signaling pathway to increase lipid oxidation and decrease lipid synthesis in bovine hepatocytes, thereby reducing liver fat accumulation in dairy cows.

Associations Between Adiposity and Metabolic Syndrome Over Time: The Healthy Twin Study.

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Song, Yun-Mi; Sung, Joohon; Lee, Kayoung

2017-04-01

We evaluated the association between changes in adiposity traits including anthropometric and fat mass indicators and changes in metabolic syndrome traits including metabolic syndrome clustering and individual components over time. We also assessed the shared genetic and environmental correlations between the two traits. Participants were 284 South Korean twin individuals and 279 nontwin family members had complete data for changes in adiposity traits and metabolic syndrome traits of the Healthy Twin study. Mixed linear model and bivariate variance-component analysis were applied. Over a period of 3.1 ± 0.6 years of study, changes in adiposity traits [body mass index (BMI), waist circumference, total fat mass, and fat mass to lean mass ratio] had significant associations with changes in metabolic syndrome clustering [high blood pressure, high serum glucose, high triglycerides (TG), and low high-density lipoprotein cholesterol] after adjusting for intra-familial and sibling correlations, age, sex, baseline metabolic syndrome clustering, and socioeconomic factors and health behaviors at follow-up. Change in BMI associated significantly with changes in individual metabolic syndrome components compared to other adiposity traits. Change in metabolic syndrome component TG was a better predictor of changes in adiposity traits compared to changes in other metabolic components. These associations were explained by significant environmental correlations but not by genetic correlations. Changes in anthropometric and fat mass indicators were positively associated with changes in metabolic syndrome clustering and those associations appeared to be regulated by environmental influences.

Effects of dietary fat energy restriction and fish oil feeding on hepatic metabolic abnormalities and insulin resistance in KK mice with high-fat diet-induced obesity.

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Arai, Takeshi; Kim, Hyoun-ju; Hirako, Satoshi; Nakasatomi, Maki; Chiba, Hiroshige; Matsumoto, Akiyo

2013-01-01

We investigated the effects of dietary fat energy restriction and fish oil intake on glucose and lipid metabolism in female KK mice with high-fat (HF) diet-induced obesity. Mice were fed a lard/safflower oil (LSO50) diet consisting of 50 energy% (en%) lard/safflower oil as the fat source for 12 weeks. Then, the mice were fed various fat energy restriction (25 en% fat) diets - LSO, FO2.5, FO12.5 or FO25 - containing 0, 2.5, 12.5, or 25 en% fish oil, respectively, for 9 weeks. Conversion from a HF diet to each fat energy restriction diet significantly decreased final body weights and visceral and subcutaneous fat mass in all fat energy restriction groups, regardless of fish oil contents. Hepatic triglyceride and cholesterol levels markedly decreased in the FO12.5 and FO25 groups, but not in the LSO group. Although plasma insulin levels did not differ among groups, the blood glucose areas under the curve in the oral glucose tolerance test were significantly lower in the FO12.5 and FO25 groups. Real-time polymerase chain reaction analysis showed fatty acid synthase mRNA levels significantly decreased in the FO25 group, and stearoyl-CoA desaturase 1 mRNA levels markedly decreased in the FO12.5 and FO25 groups. These results demonstrate that body weight gains were suppressed by dietary fat energy restriction even in KK mice with HF diet-induced obesity. We also suggested that the combination of fat energy restriction and fish oil feeding decreased fat droplets and ameliorated hepatic hypertrophy and insulin resistance with suppression of de novo lipogenesis in these mice. Copyright © 2013 Elsevier Inc. All rights reserved.

Non-alcoholic fatty liver disease and subclinical atherosclerosis: A comparison of metabolically- versus genetically-driven excess fat hepatic storage.

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Di Costanzo, Alessia; D'Erasmo, Laura; Polimeni, Licia; Baratta, Francesco; Coletta, Paola; Di Martino, Michele; Loffredo, Lorenzo; Perri, Ludovica; Ceci, Fabrizio; Montali, Anna; Girelli, Gabriella; De Masi, Bruna; Angeloni, Antonio; Catalano, Carlo; Maranghi, Marianna; Del Ben, Maria; Angelico, Francesco; Arca, Marcello

2017-02-01

Non-alcoholic fatty liver disease (NAFLD) is frequently associated with atherosclerosis. However, it is unclear whether this association is related to excess fat liver storage per se or to metabolic abnormalities that typically accompany NAFLD. To investigate this, we compared individuals with hepatic steatosis driven by metabolic disturbances to those with hepatic steatosis associated with the rs738409 GG genotype in the patatin-like phospholipase domain-containing 3 gene (PNPLA3). Carotid intima-media thickness (CIMT), as a surrogate marker of subclinical atherosclerosis, was measured in 83 blood donors with the mutant GG genotype (group G), 100 patients with features of metabolic syndrome (MetS) but the wildtype CC genotype (group M), and 74 blood donors with the wildtype CC genotype (controls). Fatty liver was evaluated by ultrasonography and hepatic fat fraction (HFF) was measured using magnetic resonance (MRS/MRI) in 157 subjects. Compared with group G and controls, group M subjects were older and had increased adiposity indices, dyslipidemia, insulin resistance and elevated transaminase levels (all p hepatic steatosis), the median CIMT in group M (0.84 [0.70-0.95] mm) was significantly greater than that in group G (0.66 [0.55-0.74] mm; p < 0.001), which was similar to that in controls (0.70 [0.64-0.81] mm). Results were similar in the subgroup evaluated using MRS/MRI. Excess liver fat accumulation appeared to increase the burden of subclinical atherosclerosis only when it is associated with metabolic abnormalities. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The relationship between fat depot-specific preadipocyte differentiation and metabolic syndrome in obese women

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N V Mazurina

2013-03-01

Full Text Available Реферат по материалам статьи The relationship between fat depot-specific preadipocyte differentiation and metabolic syndrome in obese women. Park HТ, Lee ES, Cheon EP, Lee DR, Yang K-S, Kim YT, Hur JY, Kim SH, Lee KW, Kim T. Clinical Endocrinology 2012; 76, 59-66.

High Dietary Fat Selectively Increases Catalase Expression within Cardiac Mitochondria*

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Rindler, Paul M.; Plafker, Scott M.; Szweda, Luke I.; Kinter, Michael

2013-01-01

Obesity is a predictor of diabetes and cardiovascular disease. One consequence of obesity is dyslipidemia characterized by high blood triglycerides. It has been proposed that oxidative stress, driven by utilization of lipids for energy, contributes to these diseases. The effects of oxidative stress are mitigated by an endogenous antioxidant enzyme network, but little is known about its response to high fat utilization. Our experiments used a multiplexed quantitative proteomics method to measure antioxidant enzyme expression in heart tissue in a mouse model of diet-induced obesity. This experiment showed a rapid and specific up-regulation of catalase protein, with subsequent assays showing increases in activity and mRNA. Catalase, traditionally considered a peroxisomal protein, was found to be present in cardiac mitochondria and significantly increased in content and activity during high fat feeding. These data, coupled with the fact that fatty acid oxidation enhances mitochondrial H2O2 production, suggest that a localized catalase increase is needed to consume excessive mitochondrial H2O2 produced by increased fat metabolism. To determine whether the catalase-specific response is a common feature of physiological conditions that increase blood triglycerides and fatty acid oxidation, we measured changes in antioxidant expression in fasted versus fed mice. Indeed, a similar specific catalase increase was observed in mice fasted for 24 h. Our findings suggest a fundamental metabolic process in which catalase expression is regulated to prevent damage while preserving an H2O2-mediated sensing of diet composition that appropriately adjusts insulin sensitivity in the short term as needed to prioritize lipid metabolism for complete utilization. PMID:23204527

Gender-specific increase in susceptibility to metabolic syndrome of offspring rats after prenatal caffeine exposure with post-weaning high-fat diet

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Li, Jing [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Luo, Hanwen [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Wu, Yimeng; He, Zheng; Zhang, Li; Guo, Yu [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Ma, Lu [Department of Epidemiology & Health Statistics, Public Health School of Wuhan University, Wuhan 430071 (China); Magdalou, Jacques [UMR 7561 CNRS-NancyUniversité, Faculté de Médicine, Vandoeuvre-lès-Nancy (France); Chen, Liaobin [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan 430071 (China); Wang, Hui, E-mail: wanghui19@whu.edu.cn [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan 430071 (China)

2015-05-01

Prenatal caffeine exposure (PCE) alters the hypothalamic–pituitary–adrenocortical (HPA) axis-associated neuroendocrine metabolic programming and induces an increased susceptibility to metabolic syndrome (MS) in intrauterine growth retardation (IUGR) offspring rats. High-fat diet (HFD) is one of the main environmental factors accounting for the incidence of MS. In this study, we aimed to clarify the gender-specific increase in susceptibility to MS in offspring rats after PCE with post-weaning HFD. Maternal Wistar rats were administered with caffeine (120 mg/kg·d) from gestational day 11 until delivery. The offspring rats with normal diet or HFD were euthanized at postnatal week 24, and blood samples were collected. Results showed that PCE not only reduced serum adrenocorticotropic hormone (ACTH) and corticosterone levels, but also enhanced serum glucose, triglyceride and total cholesterol (TCH) concentrations in the offspring rats. Moreover, several interactions among PCE, HFD and gender were observed by a three-way ANOVA analysis. In PCE offspring, HFD could aggravate the degree of increased serum triglyceride level. Meanwhile, serum corticosterone levels of females were decreased more obviously than those of males in PCE offspring. The results also revealed interactions between HFD and gender in the levels of serum ACTH, triglyceride and TCH, which were changed more evidently in female HFD offspring. These results indicate that HFD could exacerbate the dysfunction of lipid metabolism and the susceptibility to MS induced by PCE, and the female offspring are more sensitive to HFD-induced neuroendocrine metabolic dysfunction than their male counterparts. - Highlights: • Caffeine induced HPA axis dysfunction in offspring rats fed by high-fat diet (HFD). • Caffeine induced an increased susceptibility to metabolic syndrome. • HFD aggravated susceptibility to metabolic syndrome induced by caffeine. • Female was more sensitive to HFD-induced neuroendocrine

Gender-specific increase in susceptibility to metabolic syndrome of offspring rats after prenatal caffeine exposure with post-weaning high-fat diet

International Nuclear Information System (INIS)

Li, Jing; Luo, Hanwen; Wu, Yimeng; He, Zheng; Zhang, Li; Guo, Yu; Ma, Lu; Magdalou, Jacques; Chen, Liaobin; Wang, Hui

2015-01-01

Prenatal caffeine exposure (PCE) alters the hypothalamic–pituitary–adrenocortical (HPA) axis-associated neuroendocrine metabolic programming and induces an increased susceptibility to metabolic syndrome (MS) in intrauterine growth retardation (IUGR) offspring rats. High-fat diet (HFD) is one of the main environmental factors accounting for the incidence of MS. In this study, we aimed to clarify the gender-specific increase in susceptibility to MS in offspring rats after PCE with post-weaning HFD. Maternal Wistar rats were administered with caffeine (120 mg/kg·d) from gestational day 11 until delivery. The offspring rats with normal diet or HFD were euthanized at postnatal week 24, and blood samples were collected. Results showed that PCE not only reduced serum adrenocorticotropic hormone (ACTH) and corticosterone levels, but also enhanced serum glucose, triglyceride and total cholesterol (TCH) concentrations in the offspring rats. Moreover, several interactions among PCE, HFD and gender were observed by a three-way ANOVA analysis. In PCE offspring, HFD could aggravate the degree of increased serum triglyceride level. Meanwhile, serum corticosterone levels of females were decreased more obviously than those of males in PCE offspring. The results also revealed interactions between HFD and gender in the levels of serum ACTH, triglyceride and TCH, which were changed more evidently in female HFD offspring. These results indicate that HFD could exacerbate the dysfunction of lipid metabolism and the susceptibility to MS induced by PCE, and the female offspring are more sensitive to HFD-induced neuroendocrine metabolic dysfunction than their male counterparts. - Highlights: • Caffeine induced HPA axis dysfunction in offspring rats fed by high-fat diet (HFD). • Caffeine induced an increased susceptibility to metabolic syndrome. • HFD aggravated susceptibility to metabolic syndrome induced by caffeine. • Female was more sensitive to HFD-induced neuroendocrine

Determinants of human adipose tissue gene expression: impact of diet, sex, metabolic status, and cis genetic regulation.

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Nathalie Viguerie

2012-09-01

Full Text Available Weight control diets favorably affect parameters of the metabolic syndrome and delay the onset of diabetic complications. The adaptations occurring in adipose tissue (AT are likely to have a profound impact on the whole body response as AT is a key target of dietary intervention. Identification of environmental and individual factors controlling AT adaptation is therefore essential. Here, expression of 271 transcripts, selected for regulation according to obesity and weight changes, was determined in 515 individuals before, after 8-week low-calorie diet-induced weight loss, and after 26-week ad libitum weight maintenance diets. For 175 genes, opposite regulation was observed during calorie restriction and weight maintenance phases, independently of variations in body weight. Metabolism and immunity genes showed inverse profiles. During the dietary intervention, network-based analyses revealed strong interconnection between expression of genes involved in de novo lipogenesis and components of the metabolic syndrome. Sex had a marked influence on AT expression of 88 transcripts, which persisted during the entire dietary intervention and after control for fat mass. In women, the influence of body mass index on expression of a subset of genes persisted during the dietary intervention. Twenty-two genes revealed a metabolic syndrome signature common to men and women. Genetic control of AT gene expression by cis signals was observed for 46 genes. Dietary intervention, sex, and cis genetic variants independently controlled AT gene expression. These analyses help understanding the relative importance of environmental and individual factors that control the expression of human AT genes and therefore may foster strategies aimed at improving AT function in metabolic diseases.

Integration of Genome Scale Metabolic Networks and Gene Regulation of Metabolic Enzymes With Physiologically Based Pharmacokinetics.

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Maldonado, Elaina M; Leoncikas, Vytautas; Fisher, Ciarán P; Moore, J Bernadette; Plant, Nick J; Kierzek, Andrzej M

2017-11-01

The scope of physiologically based pharmacokinetic (PBPK) modeling can be expanded by assimilation of the mechanistic models of intracellular processes from systems biology field. The genome scale metabolic networks (GSMNs) represent a whole set of metabolic enzymes expressed in human tissues. Dynamic models of the gene regulation of key drug metabolism enzymes are available. Here, we introduce GSMNs and review ongoing work on integration of PBPK, GSMNs, and metabolic gene regulation. We demonstrate example models. © 2017 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

High-fat diet-induced adiposity, adipose inflammation, hepatic steatosis and hyperinsulinemia in outbred CD-1 mice.

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Mingming Gao

Full Text Available High-fat diet (HFD has been applied to a variety of inbred mouse strains to induce obesity and obesity related metabolic complications. In this study, we determined HFD induced development of metabolic disorders on outbred female CD-1 mice in a time dependent manner. Compared to mice on regular chow, HFD-fed CD-1 mice gradually gained more fat mass and consequently exhibited accelerated body weight gain, which was associated with adipocyte hypertrophy and up-regulated expression of adipose inflammatory chemokines and cytokines such as Mcp-1 and Tnf-α. Increased fat accumulation in white adipose tissue subsequently led to ectopic fat deposition in brown adipose tissue, giving rise to whitening of brown adipose tissue without altering plasma level of triglyceride. Ectopic fat deposition was also observed in the liver, which was associated with elevated expression of key genes involved in hepatic lipid sequestration, including Ppar-γ2, Cd36 and Mgat1. Notably, adipose chronic inflammation and ectopic lipid deposition in the liver and brown fat were accompanied by glucose intolerance and insulin resistance, which was correlated with hyperinsulinemia and pancreatic islet hypertrophy. Collectively, these results demonstrate sequentially the events that HFD induces physiological changes leading to metabolic disorders in an outbred mouse model more closely resembling heterogeneity of the human population.

A high-fat diet differentially affects the gut metabolism and blood lipids of rats depending on the type of dietary fat and carbohydrate.

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Jurgoński, Adam; Juśkiewicz, Jerzy; Zduńczyk, Zenon

2014-02-03

The aim of this model study was to investigate how selected gut functions and serum lipid profile in rats on high-fat diets differed according to the type of fat (saturated vs. unsaturated) and carbohydrate (simple vs. complex). The experiment was conducted using 32 male Wistar rats distributed into 4 groups of 8 animals each. For 4 weeks, the animals were fed group-specific diets that were either rich in lard or soybean oil (16% of the diet) as the source of saturated or unsaturated fatty acids, respectively; further, each lard- and soybean oil-rich diet contained either fructose or corn starch (45.3% of the diet) as the source of simple or complex carbohydrates, respectively. Both dietary factors contributed to changes in the caecal short-chain fatty acid concentrations, especially to the butyrate concentration, which was higher in rats fed lard- and corn starch-rich diets compared to soybean oil- and fructose-rich diets, respectively. The lowest butyrate concentration was observed in rats fed the soybean oil- and fructose-rich diet. On the other hand, the lard- and fructose-rich diet vs. the other dietary combinations significantly increased serum total cholesterol concentration, to more than two times serum triglyceride concentration and to more than five times the atherogenic index. In conclusion, a high-fat diet rich in fructose can unfavorably affect gut metabolism when unsaturated fats are predominant in the diet or the blood lipids when a diet is rich in saturated fats.

A High-Fat Diet Differentially Affects the Gut Metabolism and Blood Lipids of Rats Depending on the Type of Dietary Fat and Carbohydrate

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Adam Jurgoński

2014-02-01

Full Text Available The aim of this model study was to investigate how selected gut functions and serum lipid profile in rats on high-fat diets differed according to the type of fat (saturated vs. unsaturated and carbohydrate (simple vs. complex. The experiment was conducted using 32 male Wistar rats distributed into 4 groups of 8 animals each. For 4 weeks, the animals were fed group-specific diets that were either rich in lard or soybean oil (16% of the diet as the source of saturated or unsaturated fatty acids, respectively; further, each lard- and soybean oil-rich diet contained either fructose or corn starch (45.3% of the diet as the source of simple or complex carbohydrates, respectively. Both dietary factors contributed to changes in the caecal short-chain fatty acid concentrations, especially to the butyrate concentration, which was higher in rats fed lard- and corn starch-rich diets compared to soybean oil- and fructose-rich diets, respectively. The lowest butyrate concentration was observed in rats fed the soybean oil- and fructose-rich diet. On the other hand, the lard- and fructose-rich diet vs. the other dietary combinations significantly increased serum total cholesterol concentration, to more than two times serum triglyceride concentration and to more than five times the atherogenic index. In conclusion, a high-fat diet rich in fructose can unfavorably affect gut metabolism when unsaturated fats are predominant in the diet or the blood lipids when a diet is rich in saturated fats.

Protective effects of ethanolic extract of Zingiber officinale rhizome on the development of metabolic syndrome in high-fat diet-fed rats.

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Nammi, Srinivas; Sreemantula, Satyanarayana; Roufogalis, Basil D

2009-05-01

Metabolic syndrome, including obesity, dyslipidaemia, hyperglycaemia and insulin resistance that predisposes type 2 diabetes is a major disease problem around the world and a plethora of herbal medicines are claimed to be effective in controlling these disorders. The rhizome of Zingiber officinale (Zingiberaceae) is commonly used as a spice in various foods and beverages. Apart from its other traditional medical uses, Z. officinale has been used to control diabetes and dyslipidaemia. In the present study, the protective effects of an ethanolic extract of Z. officinale on the development of metabolic syndrome were investigated in a high-fat diet-fed rat model at doses of 100, 200 and 400 mg/kg body weight. The marked rise in body weights, glucose, insulin, total cholesterol, LDL cholesterol, triglycerides, free fatty acids and phospholipids in serum of the rats that followed 6 weeks of high-fat diet treatment were significantly reduced by Z. officinale treatment. However, no significant change in serum HDL cholesterol was observed either with high-fat diet or Z. officinale compared to both control groups. The present results provide scientific evidence to substantiate the traditional use of Z. officinale in preventing metabolic disorders.

Dietary cholesterol and fats at a young age : do they influence cholesterol metabolism in adult life?

NARCIS (Netherlands)

Temmerman, A.M.; Vonk, R.J.; Niezen-Koning, K.; Berger, R.; Fernandes, J.

1989-01-01

The effects of dietary cholesterol and fats on cholesterol metabolism later in life were studied in Mongolian gerbils. Three groups were given a basic diet with soybean oil, palm kernel oil amounting to 8.75% (w/w), or the basic diet only. In three other groups, cholesterol (0.05%) was added to the

NUCKS Is a Positive Transcriptional Regulator of Insulin Signaling

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Beiying Qiu

2014-06-01

Full Text Available Although much is known about the molecular players in insulin signaling, there is scant information about transcriptional regulation of its key components. We now find that NUCKS is a transcriptional regulator of the insulin signaling components, including the insulin receptor (IR. Knockdown of NUCKS leads to impaired insulin signaling in endocrine cells. NUCKS knockout mice exhibit decreased insulin signaling and increased body weight/fat mass along with impaired glucose tolerance and reduced insulin sensitivity, all of which are further exacerbated by a high-fat diet (HFD. Genome-wide ChIP-seq identifies metabolism and insulin signaling as NUCKS targets. Importantly, NUCKS is downregulated in individuals with a high body mass index and in HFD-fed mice, and conversely, its levels increase upon starvation. Altogether, NUCKS is a physiological regulator of energy homeostasis and glucose metabolism that works by regulating chromatin accessibility and RNA polymerase II recruitment to the promoters of IR and other insulin pathway modulators.

Influence of muscle fiber type composition on early fat accumulation under high-fat diet challenge.

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Hua, Ning; Takahashi, Hirokazu; Yee, Grace M; Kitajima, Yoichiro; Katagiri, Sayaka; Kojima, Motoyasu; Anzai, Keizo; Eguchi, Yuichiro; Hamilton, James A

2017-01-01

To investigate whether differences in muscle fiber types affect early-stage fat accumulation, under high fat diet challenge in mice. Twelve healthy male C57BL/6 mice experienced with short-term (6 weeks) diet treatment for the evaluation of early pattern changes in muscular fat. The mice were randomly divided into two groups: high fat diet (n = 8) and normal control diet (n = 4). Extra- and intra-myocellular lipid (EMCL and IMCL) in lumbar muscles (type I fiber predominant) and tibialis anterior (TA) muscle (type II fiber predominant) were determined using magnetic resonance spectroscopy (MRS). Correlation of EMCL, IMCL and their ratio between TA and lumbar muscles was evaluated. EMCL increased greatly in both muscle types after high fat diet. IMCL in TA and lumbar muscles increased to a much lower extent, with a slightly greater increase in TA muscles. EMCLs in the 2 muscles were positively correlated (r = 0.84, p = 0.01), but IMCLs showed a negative relationship (r = -0.84, p = 0.01). In lumbar muscles, high fat diet significantly decreased type I fiber while it increased type II fiber (all p≤0.001). In TA muscle, there was no significant fiber type shifting (p>0.05). Under short-time high fat diet challenge, lipid tends to initially accumulate extra-cellularly. In addition, compared to type II dominant muscle, Type I dominant muscle was less susceptible to IMCL accumulation but more to fiber type shifting. These phenomena might reflect compensative responses of skeletal muscle to dietary lipid overload in order to regulate metabolic homeostasis.

Sirtuins as regulators of the yeast metabolic network

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Markus eRalser

2012-03-01

Full Text Available There is growing evidence that the metabolic network is an integral regulator of cellularphysiology. Dynamic changes in metabolite concentrations, metabolic flux, or networktopology act as reporters of biological or environmental signals, and are required for the cellto trigger an appropriate biological reaction. Changes in the metabolic network are recognizedby specific sensory macromolecules and translated into a transcriptional or translationalresponse. The protein family of sirtuins, discovered more than 30 years ago as regulators ofsilent chromatin, seems to fulfill the role of a metabolic sensor during aging and conditions ofcaloric restriction. NAD+/NADH interconverting metabolic enzymes glyceraldehyde-3-phosphate dehydrogenase and alcohol dehydrogenase, as well as enzymes involved inNAD(H, synthesis provide or deprive NAD+ in close proximity to Sir2. This influence sirtuinactivity, and facilitates a dynamic response of the metabolic network to changes inmetabolism with effects on physiology and aging. The molecular network downstream Sir2,however, is complex. In just two orders, Sir2’s metabolism-related interactions span half ofthe yeast proteome, and are connected with virtually every physiological process. Thus,although it is fundamental to analyze single molecular mechanisms, it is at the same timecrucial to consider this genome-scale complexity when correlating single molecular eventswith phenotypes such as aging, cell growth, or stress resistance.

A fat-derived metabolite regulates a peptidergic feeding circuit in Drosophila.

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Do-Hyoung Kim

2017-03-01

Full Text Available Here, we show that the enzymatic cofactor tetrahydrobiopterin (BH4 inhibits feeding in Drosophila. BH4 biosynthesis requires the sequential action of the conserved enzymes Punch, Purple, and Sepiapterin Reductase (Sptr. Although we observe increased feeding upon loss of Punch and Purple in the adult fat body, loss of Sptr must occur in the brain. We found Sptr expression is required in four adult neurons that express neuropeptide F (NPF, the fly homologue of the vertebrate appetite regulator neuropeptide Y (NPY. As expected, feeding flies BH4 rescues the loss of Punch and Purple in the fat body and the loss of Sptr in NPF neurons. Mechanistically, we found BH4 deficiency reduces NPF staining, likely by promoting its release, while excess BH4 increases NPF accumulation without altering its expression. We thus show that, because of its physically distributed biosynthesis, BH4 acts as a fat-derived signal that induces satiety by inhibiting the activity of the NPF neurons.

Changes in body weight and metabolic indexes in overweight breast cancer survivors enrolled in a randomized trial of low-fat vs. reduced carbohydrate diets.

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Thomson, Cynthia A; Stopeck, Alison T; Bea, Jennifer W; Cussler, Ellen; Nardi, Emily; Frey, Georgette; Thompson, Patricia A

2010-01-01

Overweight status is common among women breast cancer survivors and places them at greater risk for metabolic disorders, cardiovascular morbidity, and breast cancer recurrence than nonoverweight survivors. Efforts to promote weight control in this population are needed. The objective of this research was to evaluate the effect of low-fat or low-carbohydrate diet counseling on weight loss, body composition, and changes in metabolic indexes in overweight postmenopausal breast cancer survivors. Survivors (n = 40) were randomized to receive dietitian counseling for a low-fat or a reduced carbohydrate diet for 6 mo. Weight and metabolic measures, including glucose, insulin, HbA1c, HOMA, lipids, hsCRP, as well as blood pressure were measured at baseline, 6, 12 and 24 wk. Dietary intake of fat and carbohydrate was reduced by 24 and 76 g/day, respectively. Weight loss averaged 6.1 (± 4.8 kg) at 24 wk and was not significantly different by diet group; loss of lean mass was also demonstrated. All subjects demonstrated improvements in total/HDL cholesterol ratio, and significant reductions in HbA1c, insulin, and HOMA. Triglycerides levels were significantly reduced only in the low-carbohydrate diet group (-31.1 ± 36.6; P = 0.01). Significant improvements in weight and metabolic indexes can be demonstrated among overweight breast cancer survivors adherent to either a carbohydrate- or fat-restricted diet.

High-fat diet decreases energy expenditure and expression of genes controlling lipid metabolism, mitochondrial function and skeletal system development in the adipose tissue, along with increased expression of extracellular matrix remodelling- and inflammation-related genes.

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Choi, Myung-Sook; Kim, Young-Je; Kwon, Eun-Young; Ryoo, Jae Young; Kim, Sang Ryong; Jung, Un Ju

2015-03-28

The aim of the present study was to identify the genes differentially expressed in the visceral adipose tissue in a well-characterised mouse model of high-fat diet (HFD)-induced obesity. Male C57BL/6J mice (n 20) were fed either HFD (189 % of energy from fat) or low-fat diet (LFD, 42 % of energy from fat) for 16 weeks. HFD-fed mice exhibited obesity, insulin resistance, dyslipidaemia and adipose collagen accumulation, along with higher levels of plasma leptin, resistin and plasminogen activator inhibitor type 1, although there were no significant differences in plasma cytokine levels. Energy intake was similar in the two diet groups owing to lower food intake in the HFD group; however, energy expenditure was also lower in the HFD group than in the LFD group. Microarray analysis revealed that genes related to lipolysis, fatty acid metabolism, mitochondrial energy transduction, oxidation-reduction, insulin sensitivity and skeletal system development were down-regulated in HFD-fed mice, and genes associated with extracellular matrix (ECM) components, ECM remodelling and inflammation were up-regulated. The top ten up- or down-regulated genes include Acsm3, mt-Nd6, Fam13a, Cyp2e1, Rgs1 and Gpnmb, whose roles in the deterioration of obesity-associated adipose tissue are poorly understood. In conclusion, the genes identified here provide new therapeutic opportunities for prevention and treatment of diet-induced obesity.

Anti-Obesity Effect of 6,8-Diprenylgenistein, an Isoflavonoid of Cudrania tricuspidata Fruits in High-Fat Diet-Induced Obese Mice

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Yang Hee Jo

2015-12-01

Full Text Available Obesity, which is characterized by excessive fat accumulation, is associated with several pathological disorders, including metabolic diseases. In this study, the anti-obesity effect of 6,8-diprenylgenistein (DPG, a major isoflavonoid of Cudrania tricuspidata fruits was investigated using high fat-diet (HFD-induced obese mice at the doses of 10 and 30 mg/kg for six week. The body weight of the DPG-treated groups was significantly lower compared to the HFD-treated group. In addition, fat accumulation in epididymal adipose tissue and liver was dramatically decreased in the HFD + DPG groups. The food efficiency ratios of the HFD + DPG groups were also lower compared to the HFD group with the same food intake. Metabolic parameters that had increased in the HFD group were decreased in the HFD + DPG groups. Further studies demonstrate that DPG efficiently reduces lipogenic genes by regulation of transcription factors, such as peroxisome proliferator-activated receptor γ (PPARγ and CCAAT/enhancer-binding protein α (C/EBPα, and hormones, such as leptin and adiponection. DPG also regulates acetyl-CoA carboxylase (ACC and hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR by AMP-activated protein kinase (AMPK activation. Taken together, DPG is beneficial for the regulation of obesity, especially resulting from high fat intake.

Feeding and metabolic consequences of scheduled consumption of large, binge-type meals of high fat diet in the Sprague-Dawley rat.

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Bake, T; Morgan, D G A; Mercer, J G

2014-04-10

Providing rats and mice with access to palatable high fat diets for a short period each day induces the consumption of substantial binge-like meals. Temporal food intake structure (assessed using the TSE PhenoMaster/LabMaster system) and metabolic outcomes (oral glucose tolerance tests [oGTTs], and dark phase glucose and insulin profiles) were examined in Sprague-Dawley rats given access to 60% high fat diet on one of 3 different feeding regimes: ad libitum access (HF), daily 2 h-scheduled access from 6 to 8 h into the dark phase (2 h-HF), and twice daily 1 h-scheduled access from both 1-2 h and 10-11 h into the dark phase (2×1 h-HF). Control diet remained available during the scheduled access period. HF rats had the highest caloric intake, body weight gain, body fat mass and plasma insulin. Both schedule-fed groups rapidly adapted their feeding behaviour to scheduled access, showing large meal/bingeing behaviour with 44% or 53% of daily calories consumed from high fat diet during the 2 h or 2×1 h scheduled feed(s), respectively. Both schedule-fed groups had an intermediate caloric intake and body fat mass compared to HF and control (CON) groups. Temporal analysis of food intake indicated that schedule-fed rats consumed large binge-type high fat meals without a habitual decrease in preceding intake on control diet, suggesting that a relative hypocaloric state was not responsible or required for driving the binge episode, and substantiating previous indications that binge eating may not be driven by hypothalamic energy balance neuropeptides. In an oGTT, both schedule-fed groups had impaired glucose tolerance with higher glucose and insulin area under the curve, similar to the response in ad libitum HF fed rats, suggesting that palatable feeding schedules represent a potential metabolic threat. Scheduled feeding on high fat diet produces similar metabolic phenotypes to mandatory (no choice) high fat feeding and may be a more realistic platform for mechanistic study

Feeding and metabolic consequences of scheduled consumption of large, binge-type meals of high fat diet in the Sprague–Dawley rat

Science.gov (United States)

Bake, T.; Morgan, D.G.A.; Mercer, J.G.

2014-01-01

Providing rats and mice with access to palatable high fat diets for a short period each day induces the consumption of substantial binge-like meals. Temporal food intake structure (assessed using the TSE PhenoMaster/LabMaster system) and metabolic outcomes (oral glucose tolerance tests [oGTTs], and dark phase glucose and insulin profiles) were examined in Sprague–Dawley rats given access to 60% high fat diet on one of 3 different feeding regimes: ad libitum access (HF), daily 2 h-scheduled access from 6 to 8 h into the dark phase (2 h-HF), and twice daily 1 h-scheduled access from both 1–2 h and 10–11 h into the dark phase (2 × 1 h-HF). Control diet remained available during the scheduled access period. HF rats had the highest caloric intake, body weight gain, body fat mass and plasma insulin. Both schedule-fed groups rapidly adapted their feeding behaviour to scheduled access, showing large meal/bingeing behaviour with 44% or 53% of daily calories consumed from high fat diet during the 2 h or 2 × 1 h scheduled feed(s), respectively. Both schedule-fed groups had an intermediate caloric intake and body fat mass compared to HF and control (CON) groups. Temporal analysis of food intake indicated that schedule-fed rats consumed large binge-type high fat meals without a habitual decrease in preceding intake on control diet, suggesting that a relative hypocaloric state was not responsible or required for driving the binge episode, and substantiating previous indications that binge eating may not be driven by hypothalamic energy balance neuropeptides. In an oGTT, both schedule-fed groups had impaired glucose tolerance with higher glucose and insulin area under the curve, similar to the response in ad libitum HF fed rats, suggesting that palatable feeding schedules represent a potential metabolic threat. Scheduled feeding on high fat diet produces similar metabolic phenotypes to mandatory (no choice) high fat feeding and may be a more realistic

PPARγ Pro12Ala and ACE ID polymorphisms are associated with BMI and fat distribution, but not metabolic syndrome

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Passaro Angela

2011-12-01

Full Text Available Abstract Background Metabolic Syndrome (MetS results from the combined effect of environmental and genetic factors. We investigated the possible association of peroxisome proliferator-activated receptor-γ2 (PPARγ2 Pro12Ala and Angiotensin Converting Enzyme (ACE I/D polymorphisms with MetS and interaction between these genetic variants. Methods Three hundred sixty four unrelated Caucasian subjects were enrolled. Waist circumference, blood pressure, and body mass index (BMI were recorded. Body composition was estimated by impedance analysis; MetS was diagnosed by the NCEP-ATPIII criteria. A fasting blood sample was obtained for glucose, insulin, lipid profile determination, and DNA isolation for genotyping. Results The prevalence of MetS did not differ across PPARγ2 or ACE polymorphisms. Carriers of PPARγ2 Ala allele had higher BMI and fat-mass but lower systolic blood pressure compared with Pro/Pro homozygotes. A significant PPARγ2 gene-gender interaction was observed in the modulation of BMI, fat mass, and blood pressure, with significant associations found in women only. A PPARγ2-ACE risk genotype combination for BMI and fat mass was found, with ACE DD/PPARγ2 Ala subjects having a higher BMI (p = 0.002 and Fat Mass (p = 0.002. Pro12Ala was independently associated with waist circumference independent of BMI and gender. Conclusions Carriers of PPARγ2 Ala allele had higher BMI and fat-mass but not a worse metabolic profile, possibly because of a more favorable adipose tissue distribution. A gene interaction exists between Pro12Ala and ACE I/D on BMI and fat mass. Further studies are needed to assess the contribution of Pro12Ala polymorphism in adiposity distribution.

Hypothalamic miR-219 regulates individual metabolic differences in response to diet-induced weight cycling

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Mariana Schroeder

2018-03-01

Full Text Available Consumption of a low calorie diet is the most common approach to lose weight. While generally effective at first, it is frequently followed by a relapse where the pre-diet weight is regained, and often exceeded. This pattern of repeated weight loss/regain is referred to as weight cycling and the resulting metabolic response varies greatly between individuals. Objective: We attempted to address the issue of individual differences in the response to weight cycling in male mice. Methods: We first exposed adult wild type mice to repeated cycles of high/low fat food. Next, using a lentiviral approach, we knocked-down or over-expressed miR-219 in the ventromedial hypothalamus (VMH of an additional mouse cohort and performed a full metabolic assessment. Results: Exposure of wild type males to weight cycling resulted in the division of the cohort into subsets of resistant versus metabolic-syndrome-prone (MS animals, which differed in their metabolic profile and hypothalamic miR-219 levels. Lentiviral knock-down of miR-219 in the VMH led to exacerbation of metabolic syndrome. In contrast, over-expression of miR-219 resulted in moderation of the metabolic syndrome phenotype. Conclusions: Our results suggest a role for miR-219 in the mediation of the metabolic phenotype resulting from repeated weight cycling. Keywords: Weight cycling, Metabolic syndrome, miRNAs, Ventromedial hypothalamus, High fat diet, Diabetes

Fat intake and energy-balance effects.

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Westerterp-Plantenga, M S

2004-12-30

This paper focuses on the effects of dietary fats or fatty acids on key targets of metabolic intermediates for body-weight control, i.e. satiety, thermogenesis, fat oxidation and body composition. With respect to sensory satiety, it appeared, e.g. that linoleic acid tasters showed a different mechanism for meal termination than non-tasters did. They stopped eating linoleic acid containing food based upon satiety, whereas the non-tasters stopped eating based upon the change in pleasantness of taste. Moreover, in the normal range of body mass index, an inverse relationship was shown between % 'tasters' and BMI. In a high fat diet vs. a low fat high protein high carbohydrate diet, metabolic satiety appeared to be continuously lower and correlated positively to diet-induced energy expenditure. However, with respect to the intermeal interval, satiety appeared to be more sustained following a high fat vs. a high CHO preload, resulting in a lower meal frequency. Covert fat replacement during breakfast by sucrose polyester was successful in combination with dietary restraint, yet overt fat replacement in snacks was successful in the dietary-unrestrained subjects, i.e. those who habitually ate snacks. With respect to fat oxidation, from a respiration-chamber experiment on the effects of diacylglycerol compared (DG) to triacylglycerol (TG) intake, it was concluded that consumption of DG increased fat oxidation and beta-hydroxy-butyrate levels, but did not affect energy metabolism or triacylglycerol level. Parameters of appetite were all lowered by DG compared to TG. With respect to body composition, the effects of 13 weeks CLA supplementation in overweight subjects during weight regain were assessed. Although CLA did not affect %body-weight regain, the regain of fat-free mass was increased by CLA, independently of %body-weight regain and physical activity, and as a consequence resting metabolic rate was increased. At the same time, appetite was reduced and satiety and

The Factor Inhibiting HIF Asparaginyl Hydroxylase Regulates Oxidative Metabolism and Accelerates Metabolic Adaptation to Hypoxia.

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Sim, Jingwei; Cowburn, Andrew S; Palazon, Asis; Madhu, Basetti; Tyrakis, Petros A; Macías, David; Bargiela, David M; Pietsch, Sandra; Gralla, Michael; Evans, Colin E; Kittipassorn, Thaksaon; Chey, Yu C J; Branco, Cristina M; Rundqvist, Helene; Peet, Daniel J; Johnson, Randall S

2018-04-03

Animals require an immediate response to oxygen availability to allow rapid shifts between oxidative and glycolytic metabolism. These metabolic shifts are highly regulated by the HIF transcription factor. The factor inhibiting HIF (FIH) is an asparaginyl hydroxylase that controls HIF transcriptional activity in an oxygen-dependent manner. We show here that FIH loss increases oxidative metabolism, while also increasing glycolytic capacity, and that this gives rise to an increase in oxygen consumption. We further show that the loss of FIH acts to accelerate the cellular metabolic response to hypoxia. Skeletal muscle expresses 50-fold higher levels of FIH than other tissues: we analyzed skeletal muscle FIH mutants and found a decreased metabolic efficiency, correlated with an increased oxidative rate and an increased rate of hypoxic response. We find that FIH, through its regulation of oxidation, acts in concert with the PHD/vHL pathway to accelerate HIF-mediated metabolic responses to hypoxia. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Effect of ezetimibe on lipid and glucose metabolism after a fat and glucose load.

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Hiramitsu, Shinya; Miyagishima, Kenji; Ishii, Junichi; Matsui, Shigeru; Naruse, Hiroyuki; Shiino, Kenji; Kitagawa, Fumihiko; Ozaki, Yukio

2012-11-01

The clinical benefit of ezetimibe, an intestinal cholesterol transporter inhibitor, for treatment of postprandial hyperlipidemia was assessed in subjects who ingested a high-fat and high-glucose test meal to mimic westernized diet. We enrolled 20 male volunteers who had at least one of the following: waist circumference ≥ 85 cm, body mass index ≥ 25 kg/m(2), or triglycerides (TG) from 150 to 400mg/dL. After 4 weeks of treatment with ezetimibe (10mg/day), the subjects ingested a high-fat and high-glucose meal. Then changes in serum lipid and glucose levels were monitored after 0, 2, 4, and 6h, and the area under the curve (AUC) was calculated for the change in each parameter. At 4 and 6h postprandially, TG levels were decreased (pAUC for TG was also decreased (pAUC for apo-B48 was also significantly decreased (pBlood glucose and insulin levels at 2h postprandially were significantly decreased by ezetimibe (pAUCs for blood glucose and insulin were also significantly decreased (pglucose metabolism, this drug is likely to be beneficial for dyslipidemia in patients with postprandial metabolic abnormalities. Copyright © 2012 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Associations among eating regulation and body mass index, weight, and body fat in college students: the moderating role of gender.

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Gropper, Sareen S; Arsiwalla, Dilbur D; Lord, Denali C; Huggins, Kevin W; Simmons, Karla P; Ulrich, Pamela V

2014-04-01

This study investigated associations between eating regulation behaviors and body mass index (BMI), weight, and percent body fat in male and female students over the first two years of college. Subjects included 328 college students (215 females and 113 males). Height and weight (via standard techniques), body composition (via bioelectrical impedance analysis), and eating regulation behaviors (using the Regulation of Eating Behavior Scale) were conducted two to three times during both the freshman and sophomore years. Significant associations between eating regulation and BMI, weight, and/or percent body fat were shown mostly in females. In females, higher BMI, weight, and/or percent body fat at the end of the second year of college were found in those with low levels of autonomous, intrinsic motivation, and identified regulation, and high levels of amotivation, while lower BMI, weight, and/or percent body fat were associated with high levels of autonomous, intrinsic motivation, and identified regulation, and low levels of amotivation. The findings that specific eating behaviors in females during the first two years of college influence BMI, weight, and/or percent body fat may be useful for inclusion in university programs focused on college student health to help decrease the risk of obesity and disordered eating/eating disorders in female college students. Copyright © 2014 Elsevier Ltd. All rights reserved.

Skeletal Muscle Derived IL-6 in Liver and Adipose Tissue Metabolism

DEFF Research Database (Denmark)

Knudsen, Jakob Grunnet

Summary Physical activity can lead to metabolic disease and treatment of several metabolic diseases include exercise training. Skeletal muscle has, due to its central role in glucose and fat metabolism at rest and during exercise been studied in detail with regard to exercise training. The role...... of both liver and adipose tissue regulation in whole body metabolism has come in to focus and it has been shown that both tissues are subject to exercise training-induced adaptations. However, the contribution of endocrine factors to the regulation of exercise training-induced adaptations in liver...... and adipose tissue metabolism is unknown. It has been suggested that myokines, such as IL-6, released from skeletal muscle affects liver and adipose tissue and are involved in the regulation of exercise training adaptations. Thus, the aim of this thesis was to investigate the role of skeletal muscle derived...

Proprietary tomato extract improves metabolic response to high-fat meal in healthy normal weight subjects

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Xavier Deplanque

2016-10-01

Full Text Available Background: Low-density lipoprotein (LDL oxidation is a risk factor for atherosclerosis. Lycopene and tomato-based products have been described as potent inhibitors of LDL oxidation. Objectives: To evaluate the effect of a 2-week supplementation with a carotenoid-rich tomato extract (CRTE standardized for a 1:1 ratio of lycopene and phytosterols, on post-prandial LDL oxidation after a high-fat meal. Design: In a randomized, double-blind, parallel-groups, placebo-controlled study, 146 healthy normal weight individuals were randomly assigned to a daily dose of CRTE standardized for tomato phytonutrients or placebo during 2 weeks. Oxidized LDL (OxLDL, glucose, insulin, and triglyceride (TG responses were measured for 8 h after ingestion of a high-fat meal before and at the end of intervention. Results: Plasma lycopene, phytofluene, and phytoene were increased throughout the study period in the CRTE group compared to placebo. CRTE ingestion significantly improved changes in OxLDL response to high-fat meal compared to placebo after 2 weeks (p<0.0001. Changes observed in glucose, insulin, and TG responses were not statistically significant after 2 weeks of supplementation, although together they may suggest a trend of favorable effect on metabolic outcomes after a high-fat meal. Conclusions: Two-week supplementation with CRTE increased carotenoids levels in plasma and improved oxidized LDL response to a high-fat meal in healthy normal weight individuals.

Experimental type II diabetes and related models of impaired glucose metabolism differentially regulate glucose transporters at the proximal tubule brush border membrane.

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Chichger, Havovi; Cleasby, Mark E; Srai, Surjit K; Unwin, Robert J; Debnam, Edward S; Marks, Joanne

2016-06-01

What is the central question of this study? Although SGLT2 inhibitors represent a promising treatment for patients suffering from diabetic nephropathy, the influence of metabolic disruption on the expression and function of glucose transporters is largely unknown. What is the main finding and its importance? In vivo models of metabolic disruption (Goto-Kakizaki type II diabetic rat and junk-food diet) demonstrate increased expression of SGLT1, SGLT2 and GLUT2 in the proximal tubule brush border. In the type II diabetic model, this is accompanied by increased SGLT- and GLUT-mediated glucose uptake. A fasted model of metabolic disruption (high-fat diet) demonstrated increased GLUT2 expression only. The differential alterations of glucose transporters in response to varying metabolic stress offer insight into the therapeutic value of inhibitors. SGLT2 inhibitors are now in clinical use to reduce hyperglycaemia in type II diabetes. However, renal glucose reabsorption across the brush border membrane (BBM) is not completely understood in diabetes. Increased consumption of a Western diet is strongly linked to type II diabetes. This study aimed to investigate the adaptations that occur in renal glucose transporters in response to experimental models of diet-induced insulin resistance. The study used Goto-Kakizaki type II diabetic rats and normal rats rendered insulin resistant using junk-food or high-fat diets. Levels of protein kinase C-βI (PKC-βI), GLUT2, SGLT1 and SGLT2 were determined by Western blotting of purified renal BBM. GLUT- and SGLT-mediated d-[(3) H]glucose uptake by BBM vesicles was measured in the presence and absence of the SGLT inhibitor phlorizin. GLUT- and SGLT-mediated glucose transport was elevated in type II diabetic rats, accompanied by increased expression of GLUT2, its upstream regulator PKC-βI and SGLT1 protein. Junk-food and high-fat diet feeding also caused higher membrane expression of GLUT2 and its upstream regulator PKC

Calorie for Calorie, Dietary Fat Restriction Results in More Body Fat Loss than Carbohydrate Restriction in People with Obesity.

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Hall, Kevin D; Bemis, Thomas; Brychta, Robert; Chen, Kong Y; Courville, Amber; Crayner, Emma J; Goodwin, Stephanie; Guo, Juen; Howard, Lilian; Knuth, Nicolas D; Miller, Bernard V; Prado, Carla M; Siervo, Mario; Skarulis, Monica C; Walter, Mary; Walter, Peter J; Yannai, Laura

2015-09-01

Dietary carbohydrate restriction has been purported to cause endocrine adaptations that promote body fat loss more than dietary fat restriction. We selectively restricted dietary carbohydrate versus fat for 6 days following a 5-day baseline diet in 19 adults with obesity confined to a metabolic ward where they exercised daily. Subjects received both isocaloric diets in random order during each of two inpatient stays. Body fat loss was calculated as the difference between daily fat intake and net fat oxidation measured while residing in a metabolic chamber. Whereas carbohydrate restriction led to sustained increases in fat oxidation and loss of 53 ± 6 g/day of body fat, fat oxidation was unchanged by fat restriction, leading to 89 ± 6 g/day of fat loss, and was significantly greater than carbohydrate restriction (p = 0.002). Mathematical model simulations agreed with these data, but predicted that the body acts to minimize body fat differences with prolonged isocaloric diets varying in carbohydrate and fat. Copyright © 2015 Elsevier Inc. All rights reserved.

Imidacloprid Promotes High Fat Diet-Induced Adiposity and Insulin Resistance in Male C57BL/6J Mice.

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Sun, Quancai; Xiao, Xiao; Kim, Yoo; Kim, Daeyoung; Yoon, Kyoon Sup; Clark, John M; Park, Yeonhwa

2016-12-14

Imidacloprid, a neonicotinoid insecticide widely used in agriculture worldwide, has been reported to promote adipogenesis and cause insulin resistance in vitro. The purpose of the current study was to determine the effects of imidacloprid and its interaction with dietary fat in the development of adiposity and insulin resistance using male C57BL/6J mice. Imidacloprid (0.06, 0.6, or 6 mg/kg bw/day) was mixed in a low-fat (4% w/w) or high-fat (20% w/w) diet and given to mice ad libitum for 12 weeks. Imidacloprid significantly promoted high fat diet-induced body weight gain and adiposity. In addition, imidacloprid treatment with the high fat diet resulted in impaired glucose metabolism. Consistently, there were significant effects of imidacloprid on genes regulating lipid and glucose metabolisms, including the AMP-activated protein kinase-α (AMPKα) pathway in white adipose tissue and liver. These results suggest that imidacloprid may potentiate high fat diet-induced adiposity and insulin resistance in male C57BL/6J mice.

Activation of AMPK-Regulated CRH Neurons in the PVH is Sufficient and Necessary to Induce Dietary Preference for Carbohydrate over Fat

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Shiki Okamoto

2018-01-01

Full Text Available Food selection is essential for metabolic homeostasis and is influenced by nutritional state, food palatability, and social factors such as stress. However, the mechanism responsible for selection between a high-carbohydrate diet (HCD and a high-fat diet (HFD remains unknown. Here, we show that activation of a subset of corticotropin-releasing hormone (CRH-positive neurons in the rostral region of the paraventricular hypothalamus (PVH induces selection of an HCD over an HFD in mice during refeeding after fasting, resulting in a rapid recovery from the change in ketone metabolism. These neurons manifest activation of AMP-activated protein kinase (AMPK during food deprivation, and this activation is necessary and sufficient for selection of an HCD over an HFD. Furthermore, this effect is mediated by carnitine palmitoyltransferase 1c (CPT1c. Thus, our results identify the specific neurons and intracellular signaling pathway responsible for regulation of the complex behavior of selection between an HCD and an HFD.

Effects of Diets Differing in Composition of 18-C Fatty Acids on Adipose Tissue Thermogenic Gene Expression in Mice Fed High-Fat Diets

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Sunhye Shin

2018-02-01

Full Text Available Dietary fatty acids play important roles in the regulation of fat accumulation or metabolic phenotype of adipocytes, either as brown or beige fat. However, a systematic comparison of effects of diets with different composition of 18-C fatty acids on browning/beiging phenotype has not been done. In this study, we compared the effects of different dietary fats, rich in specific 18-carbon fatty acids, on thermogenesis and lipid metabolism. Male C57BL/6 mice were fed a control diet containing 5.6% kcal fat from lard and 4.4% kcal fat from soybean oil (CON or high-fat diets (HFD containing 25% kcal from lard and 20% kcal fat from shea butter (stearic acid-rich fat; SHB, olive oil (oleic acid-rich oil; OO, safflower oil (linoleic acid-rich oil; SFO, or soybean oil (mixed oleic, linoleic, and α-linolenic acids; SBO ad libitum for 12 weeks, with or without a terminal 4-h norepinephrine (NE treatment. When compared to SHB, feeding OO, SFO, and SBO resulted in lower body weight gain. The OO fed group had the highest thermogenesis level, which resulted in lower body fat accumulation and improved glucose and lipid metabolism. Feeding SFO downregulated expression of lipid oxidation-related genes and upregulated expression of lipogenic genes, perhaps due to its high n-6:n-3 ratio. In general, HFD-feeding downregulated Ucp1 expression in both subcutaneous and epididymal white adipose tissue, and suppressed NE-induced Pgc1a expression in brown adipose tissue. These results suggest that the position of double bonds in dietary fatty acids, as well as the quantity of dietary fat, may have a significant effect on the regulation of oxidative and thermogenic conditions in vivo.

The effect of a low-fat, high-protein or high-carbohydrate ad libitum diet on weight loss maintenance and metabolic risk factors.

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Claessens, M; van Baak, M A; Monsheimer, S; Saris, W H M

2009-03-01

High-protein (HP) diets are often advocated for weight reduction and weight loss maintenance. The aim was to compare the effect of low-fat, high-carbohydrate (HC) and low-fat, HP ad libitum diets on weight maintenance after weight loss induced by a very low-calorie diet, and on metabolic and cardiovascular risk factors in healthy obese subjects. Forty-eight subjects completed the study that consisted of an energy restriction period of 5-6 weeks followed by a weight maintenance period of 12 weeks. During weight maintenance subjects received maltodextrin (HC group) or protein (HP group) (casein (HPC subgroup) or whey (HPW subgroup)) supplements (2 x 25 g per day), respectively and consumed a low-fat diet. Subjects in the HP diet group showed significantly better weight maintenance after weight loss (2.3 kg difference, P=0.04) and fat mass reduction (2.2 kg difference, P=0.02) than subjects in the HC group. Triglyceride (0.6 mM difference, P=0.01) and glucagon (9.6 pg ml(-1) difference, P=0.02) concentrations increased more in the HC diet group, while glucose (0.3 mM difference, P=0.02) concentration increased more in the HP diet group. Changes in total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, insulin, HOMAir index, HbA1c, leptin and adiponectin concentrations did not differ between the diets. No differences were found between the casein- or whey-supplemented HP groups. These results show that low-fat, high-casein or whey protein weight maintenance diets are more effective for weight control than low-fat, HC diets and do not adversely affect metabolic and cardiovascular risk factors in weight-reduced moderately obese subjects without metabolic or cardiovascular complications.

The Mammalian "Obesogen" Tributyltin Targets Hepatic Triglyceride Accumulation and the Transcriptional Regulation of Lipid Metabolism in the Liver and Brain of Zebrafish.

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Angeliki Lyssimachou

Full Text Available Recent findings indicate that different Endocrine Disrupting Chemicals (EDCs interfere with lipid metabolic pathways in mammals and promote fat accumulation, a previously unknown site of action for these compounds. The antifoulant and environmental pollutant tributyltin (TBT, which causes imposex in gastropod snails, induces an "obesogenic" phenotype in mammals, through the activation of the nuclear receptors retinoid X receptor (RXR and peroxisome proliferator-activated receptor gamma (PPARγ. In teleosts, the effects of TBT on the lipid metabolism are poorly understood, particularly following exposure to low, environmental concentrations. In this context, the present work shows that exposure of zebrafish to 10 and 50 ng/L of TBT (as Sn from pre-hatch to 9 months of age alters the body weight, condition factor, hepatosomatic index and hepatic triglycerides in a gender and dose related manner. Furthermore, TBT modulated the transcription of key lipid regulating factors and enzymes involved in adipogenesis, lipogenesis, glucocorticoid metabolism, growth and development in the brain and liver of exposed fish, revealing sexual dimorphic effects in the latter. Overall, the present study shows that the model mammalian obesogen TBT interferes with triglyceride accumulation and the transcriptional regulation of lipid metabolism in zebrafish and indentifies the brain lipogenic transcription profile of fish as a new target of this compound.

The Mammalian "Obesogen" Tributyltin Targets Hepatic Triglyceride Accumulation and the Transcriptional Regulation of Lipid Metabolism in the Liver and Brain of Zebrafish.

Science.gov (United States)

Lyssimachou, Angeliki; Santos, Joana G; André, Ana; Soares, Joana; Lima, Daniela; Guimarães, Laura; Almeida, C Marisa R; Teixeira, Catarina; Castro, L Filipe C; Santos, Miguel M

2015-01-01

Recent findings indicate that different Endocrine Disrupting Chemicals (EDCs) interfere with lipid metabolic pathways in mammals and promote fat accumulation, a previously unknown site of action for these compounds. The antifoulant and environmental pollutant tributyltin (TBT), which causes imposex in gastropod snails, induces an "obesogenic" phenotype in mammals, through the activation of the nuclear receptors retinoid X receptor (RXR) and peroxisome proliferator-activated receptor gamma (PPARγ). In teleosts, the effects of TBT on the lipid metabolism are poorly understood, particularly following exposure to low, environmental concentrations. In this context, the present work shows that exposure of zebrafish to 10 and 50 ng/L of TBT (as Sn) from pre-hatch to 9 months of age alters the body weight, condition factor, hepatosomatic index and hepatic triglycerides in a gender and dose related manner. Furthermore, TBT modulated the transcription of key lipid regulating factors and enzymes involved in adipogenesis, lipogenesis, glucocorticoid metabolism, growth and development in the brain and liver of exposed fish, revealing sexual dimorphic effects in the latter. Overall, the present study shows that the model mammalian obesogen TBT interferes with triglyceride accumulation and the transcriptional regulation of lipid metabolism in zebrafish and indentifies the brain lipogenic transcription profile of fish as a new target of this compound.

CPT1A Missense Mutation Associated with Fatty Acid Metabolism and Reduced Height in Greenlanders

DEFF Research Database (Denmark)

Skotte, Line; Koch, Anders; Yakimov, Victor

2017-01-01

Background - Inuit have lived for thousands of years in an extremely cold environment on a diet dominated by marine-derived fat. To investigate how this selective pressure has affected the genetic regulation of fatty acid metabolism, we assessed 233 serum metabolic phenotypes in a population-base...

Novel function of the retinoblastoma protein in fat: regulation of white versus brown adipocyte differentiation

DEFF Research Database (Denmark)

Hansen, Jacob B; te Riele, Hein; Kristiansen, Karsten

2004-01-01

the major energy store and brown adipocytes being potent energy-dissipaters through thermogenesis. Yet, little is known about factors differentially regulating the formation of white and brown fat cells. Members of the retinoblastoma protein family (pRB, p107, p130) have been implicated in the regulation...... of adipocyte differentiation, and expression and phosphorylation of the three retinoblastoma family proteins oscillate in a characteristic manner during differentiation of the white preadipocyte cell line 3T3-L1. We have recently demonstrated a surprising function of the retinoblastoma protein...... in the regulation of white versus brown adipocyte differentiation in vitro and possibly in vivo. Here we summarize the current knowledge on the retinoblastoma protein in fat cells, with particular emphasis on its potential role in adipocyte lineage commitment and differentiation....

Nopal (Opuntia ficus indica) protects from metabolic endotoxemia by modifying gut microbiota in obese rats fed high fat/sucrose diet.

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Sánchez-Tapia, Mónica; Aguilar-López, Miriam; Pérez-Cruz, Claudia; Pichardo-Ontiveros, Edgar; Wang, Mei; Donovan, Sharon M; Tovar, Armando R; Torres, Nimbe

2017-07-05

Current efforts are directed to reducing the gut dysbiosis and inflammation produced by obesity. The purpose of this study was to investigate whether consuming nopal, a vegetable rich in dietary fibre, vitamin C, and polyphenols can reduce the metabolic consequences of obesity by modifying the gut microbiota and preventing metabolic endotoxemia in rats fed a high fat and sucrose diet. With this aim, rats were fed a high fat diet with 5% sucrose in the drinking water (HFS) for 7 months and then were fed for 1 month with HFS + 5% nopal (HFS + N). The composition of gut microbiota was assessed by sequencing the 16S rRNA gene. Nopal modified gut microbiota and increased intestinal occludin-1 in the HFS + N group. This was associated with a decrease in metabolic endotoxemia, glucose insulinotropic peptide, glucose intolerance, lipogenesis, and metabolic inflexibility. These changes were accompanied by reduced hepatic steatosis and oxidative stress in adipose tissue and brain, and improved cognitive function, associated with an increase in B. fragilis. This study supports the use of nopal as a functional food and prebiotic for its ability to modify gut microbiota and to reduce metabolic endotoxemia and other obesity-related biochemical abnormalities.

Estimating the continuous-time dynamics of energy and fat metabolism in mice.

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Guo, Juen; Hall, Kevin D

2009-09-01

The mouse has become the most popular organism for investigating molecular mechanisms of body weight regulation. But understanding the physiological context by which a molecule exerts its effect on body weight requires knowledge of energy intake, energy expenditure, and fuel selection. Furthermore, measurements of these variables made at an isolated time point cannot explain why body weight has its present value since body weight is determined by the past history of energy and macronutrient imbalance. While food intake and body weight changes can be frequently measured over several weeks (the relevant time scale for mice), correspondingly frequent measurements of energy expenditure and fuel selection are not currently feasible. To address this issue, we developed a mathematical method based on the law of energy conservation that uses the measured time course of body weight and food intake to estimate the underlying continuous-time dynamics of energy output and net fat oxidation. We applied our methodology to male C57BL/6 mice consuming various ad libitum diets during weight gain and loss over several weeks and present the first continuous-time estimates of energy output and net fat oxidation rates underlying the observed body composition changes. We show that transient energy and fat imbalances in the first several days following a diet switch can account for a significant fraction of the total body weight change. We also discovered a time-invariant curve relating body fat and fat-free masses in male C57BL/6 mice, and the shape of this curve determines how diet, fuel selection, and body composition are interrelated.

[Regulation of terpene metabolism]. [Mentha piperita, Mentha spicata

Energy Technology Data Exchange (ETDEWEB)

Croteau, R.

1989-01-01

Progress in understanding of the metabolism of monoterpenes by peppermint and spearmint is recorded including the actions of two key enzymes, geranyl pyrophosphate:limonene cyclase and a UDP-glucose dependent glucosyl transferase; concerning the ultrastructure of oil gland senescence; enzyme subcellular localization; regulation of metabolism; and tissue culture systems.

Characterization of fat metabolism in the fatty liver caused by a high-fat, low-carbohydrate diet: A study under equal energy conditions.

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Kurosaka, Yuka; Shiroya, Yoko; Yamauchi, Hideki; Kitamura, Hiromi; Minato, Kumiko

2017-05-20

The pathology of fatty liver due to increased percentage of calories derived from fat without increased overall caloric intake is largely unclear. In this study, we aimed to characterize fat metabolism in rats with fatty liver resulting from consumption of a high-fat, low-carbohydrate (HFLC) diet without increased caloric intake. Four-week-old male Sprague-Dawley rats were randomly assigned to the control (Con) and HFLC groups, and rats were fed the corresponding diets ad libitum. Significant decreases in food intake per gram body weight were observed in the HFLC group compared with that in the Con group. Thus, there were no significant differences in body weights or caloric intake per gram body weight between the two groups. Marked progressive fat accumulation was observed in the livers of rats in the HFLC group, accompanied by suppression of de novo lipogenesis (DNL)-related proteins in the liver and increased leptin concentrations in the blood. In addition, electron microscopic observations revealed that many lipid droplets had accumulated within the hepatocytes, and mitochondrial numbers were reduced in the hepatocytes of rats in the HFLC group. Our findings confirmed that consumption of the HFLC diet induced fatty liver, even without increased caloric intake. Furthermore, DNL was not likely to be a crucial factor inducing fatty liver with standard energy intake. Instead, ultrastructural abnormalities found in mitochondria, which may cause a decline in β-oxidation, could contribute to the development of fatty liver. Copyright © 2017 Elsevier Inc. All rights reserved.

Long-lasting improvements in liver fat and metabolism despite body weight regain after dietary weight loss.

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Haufe, Sven; Haas, Verena; Utz, Wolfgang; Birkenfeld, Andreas L; Jeran, Stephanie; Böhnke, Jana; Mähler, Anja; Luft, Friedrich C; Schulz-Menger, Jeanette; Boschmann, Michael; Jordan, Jens; Engeli, Stefan

2013-11-01

Weight loss reduces abdominal and intrahepatic fat, thereby improving metabolic and cardiovascular risk. Yet, many patients regain weight after successful diet-induced weight loss. Long-term changes in abdominal and liver fat, along with liver test results and insulin resistance, are not known. We analyzed 50 overweight to obese subjects (46 ± 9 years of age; BMI, 32.5 ± 3.3 kg/m2; women, 77%) who had participated in a 6-month hypocaloric diet and were randomized to either reduced carbohydrates or reduced fat content. Before, directly after diet, and at an average of 24 (range, 17-36) months follow-up, we assessed body fat distribution by magnetic resonance imaging and markers of liver function and insulin resistance. Body weight decreased with diet but had increased again at follow-up. Subjects also partially regained abdominal subcutaneous and visceral adipose tissue. In contrast, intrahepatic fat decreased with diet and remained reduced at follow-up (7.8 ± 9.8% [baseline], 4.5 ± 5.9% [6 months], and 4.7 ± 5.9% [follow-up]). Similar patterns were observed for markers of liver function, whole-body insulin sensitivity, and hepatic insulin resistance. Changes in intrahepatic fat und intrahepatic function were independent of macronutrient composition during intervention and were most effective in subjects with nonalcoholic fatty liver disease at baseline. A 6-month hypocaloric diet induced improvements in hepatic fat, liver test results, and insulin resistance despite regaining of weight up to 2 years after the active intervention. Body weight and adiposity measurements may underestimate beneficial long-term effects of dietary interventions.

Microencapsulated conjugated linoleic acid associated with hypocaloric diet reduces body fat in sedentary women with metabolic syndrome.

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Carvalho, Roberta F; Uehara, Sofia K; Rosa, Glorimar

2012-01-01

Animal studies have suggested beneficial effects of conjugated linoleic acid (CLA) in reducing body fat mass and improvement in the serum lipid profile and glycemia. However, these effects are controversial in humans. The purpose of this study was to investigate the effects of microencapsulated CLA supplementation on body composition, body mass index, waist circumference, and blood pressure in sedentary women with metabolic syndrome. This study was a placebo-controlled and randomized clinical trial. Fourteen women diagnosed with metabolic syndrome received light strawberry jam enriched or not with microencapsulated CLA (3 g/day) as a mixture of 38.57% cis-9, trans-11, and 39.76% trans-10, cis-12 CLA isomers associated with a hypocaloric diet for 90 days. The subjects were monitored to assess variables associated with the metabolic syndrome, in addition to assessing adherence with the intervention. There were no significant effects of microencapsulated CLA on the lipid profile or blood pressure. Mean plasma insulin concentrations were significantly lower in women supplemented with microencapsulated CLA (Δ T₉₀ - T₀ = -12.87 ± 4.26 μU/mL, P = 0.02). Microencapsulated CLA supplementation did not alter the waist circumference, but there was a reduction in body fat mass detected after 30 days (Δ = -2.68% ± 0.82%, P = 0.02), which was maintained until the 90-day intervention period (Δ = -3.32% ± 1.41%, P = 0.02) in the microencapsulated CLA group. The placebo group showed this effect only after 90 days (Δ = -1.97% ± 0.60%, P = 0.02), but had a reduced waist circumference (Δ T₉₀ - T₀ = -4.25 ± 1.31 cm, P = 0.03). Supplementation with mixed-isomer microencapsulated CLA may have a favorable effect on glycemic control and body fat mass loss at an earlier time in sedentary women with metabolic syndrome, although there were no effects on lipid profile and blood pressure.

Microencapsulated conjugated linoleic acid associated with hypocaloric diet reduces body fat in sedentary women with metabolic syndrome

Science.gov (United States)

Carvalho, Roberta F; Uehara, Sofia K; Rosa, Glorimar

2012-01-01

Background Animal studies have suggested beneficial effects of conjugated linoleic acid (CLA) in reducing body fat mass and improvement in the serum lipid profile and glycemia. However, these effects are controversial in humans. The purpose of this study was to investigate the effects of microencapsulated CLA supplementation on body composition, body mass index, waist circumference, and blood pressure in sedentary women with metabolic syndrome. Methods This study was a placebo-controlled and randomized clinical trial. Fourteen women diagnosed with metabolic syndrome received light strawberry jam enriched or not with microencapsulated CLA (3 g/day) as a mixture of 38.57% cis-9, trans-11, and 39.76% trans-10, cis-12 CLA isomers associated with a hypocaloric diet for 90 days. The subjects were monitored to assess variables associated with the metabolic syndrome, in addition to assessing adherence with the intervention. Results There were no significant effects of microencapsulated CLA on the lipid profile or blood pressure. Mean plasma insulin concentrations were significantly lower in women supplemented with microencapsulated CLA (Δ T90 – T0 = −12.87 ± 4.26 μU/mL, P = 0.02). Microencapsulated CLA supplementation did not alter the waist circumference, but there was a reduction in body fat mass detected after 30 days (Δ = −2.68% ± 0.82%, P = 0.02), which was maintained until the 90-day intervention period (Δ = −3.32% ± 1.41%, P = 0.02) in the microencapsulated CLA group. The placebo group showed this effect only after 90 days (Δ = −1.97% ± 0.60%, P = 0.02), but had a reduced waist circumference (Δ T90 – T0 = −4.25 ± 1.31 cm, P = 0.03). Conclusion Supplementation with mixed-isomer microencapsulated CLA may have a favorable effect on glycemic control and body fat mass loss at an earlier time in sedentary women with metabolic syndrome, although there were no effects on lipid profile and blood pressure. PMID:23271912

Current knowledge of microRNA-mediated regulation of drug metabolism in humans.

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Nakano, Masataka; Nakajima, Miki

2018-05-01

Understanding the factors causing inter- and intra-individual differences in drug metabolism potencies is required for the practice of personalized or precision medicine, as well as for the promotion of efficient drug development. The expression of drug-metabolizing enzymes is controlled by transcriptional regulation by nuclear receptors and transcriptional factors, epigenetic regulation, such as DNA methylation and histone acetylation, and post-translational modification. In addition to such regulation mechanisms, recent studies revealed that microRNAs (miRNAs), endogenous ~22-nucleotide non-coding RNAs that regulate gene expression through the translational repression and degradation of mRNAs, significantly contribute to post-transcriptional regulation of drug-metabolizing enzymes. Areas covered: This review summarizes the current knowledge regarding miRNAs-dependent regulation of drug-metabolizing enzymes and transcriptional factors and its physiological and clinical significance. We also describe recent advances in miRNA-dependent regulation research, showing that the presence of pseudogenes, single-nucleotide polymorphisms, and RNA editing affects miRNA targeting. Expert opinion: It is unwavering fact that miRNAs are critical factors causing inter- and intra-individual differences in the expression of drug-metabolizing enzymes. Consideration of miRNA-dependent regulation would be a helpful tool for optimizing personalized and precision medicine.

Erythropoietin over-expression protects against diet-induced obesity in mice through increased fat oxidation in muscles.

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Hojman, Pernille; Brolin, Camilla; Gissel, Hanne; Brandt, Claus; Zerahn, Bo; Pedersen, Bente Klarlund; Gehl, Julie

2009-06-12

Erythropoietin can be over-expressed in skeletal muscles by gene electrotransfer, resulting in 100-fold increase in serum EPO and significant increases in haemoglobin levels. Earlier studies have suggested that EPO improves several metabolic parameters when administered to chronically ill kidney patients. Thus we applied the EPO over-expression model to investigate the metabolic effect of EPO in vivo.At 12 weeks, EPO expression resulted in a 23% weight reduction (Pincrease in muscle volume and a 25% increase in vascularisation of the EPO transfected muscle. Muscle force and stamina were not affected by EPO expression. PCR array analysis revealed that genes involved in lipid metabolism, thermogenesis and inflammation were increased in muscles in response to EPO expression, while genes involved in glucose metabolism were down-regulated. In addition, muscular fat oxidation was increased 1.8-fold in both the EPO transfected and contralateral muscles.In conclusion, we have shown that EPO when expressed in supra-physiological levels has substantial metabolic effects including protection against diet-induced obesity and normalisation of glucose sensitivity associated with a shift to increased fat metabolism in the muscles.

Erythropoietin over-expression protects against diet-induced obesity in mice through increased fat oxidation in muscles.

Directory of Open Access Journals (Sweden)

Pernille Hojman

Full Text Available Erythropoietin can be over-expressed in skeletal muscles by gene electrotransfer, resulting in 100-fold increase in serum EPO and significant increases in haemoglobin levels. Earlier studies have suggested that EPO improves several metabolic parameters when administered to chronically ill kidney patients. Thus we applied the EPO over-expression model to investigate the metabolic effect of EPO in vivo.At 12 weeks, EPO expression resulted in a 23% weight reduction (P<0.01 in EPO transfected obese mice; thus the mice weighed 21.9+/-0.8 g (control, normal diet, 21.9+/-1.4 g (EPO, normal diet, 35.3+/-3.3 g (control, high-fat diet and 28.8+/-2.6 g (EPO, high-fat diet. Correspondingly, DXA scanning revealed that this was due to a 28% reduction in adipose tissue mass.The decrease in adipose tissue mass was accompanied by a complete normalisation of fasting insulin levels and glucose tolerance in the high-fat fed mice. EPO expression also induced a 14% increase in muscle volume and a 25% increase in vascularisation of the EPO transfected muscle. Muscle force and stamina were not affected by EPO expression. PCR array analysis revealed that genes involved in lipid metabolism, thermogenesis and inflammation were increased in muscles in response to EPO expression, while genes involved in glucose metabolism were down-regulated. In addition, muscular fat oxidation was increased 1.8-fold in both the EPO transfected and contralateral muscles.In conclusion, we have shown that EPO when expressed in supra-physiological levels has substantial metabolic effects including protection against diet-induced obesity and normalisation of glucose sensitivity associated with a shift to increased fat metabolism in the muscles.

Amino acid metabolism in dairy cows and their regulation in milk synthesis.

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Wang, Feiran; Shi, Haitao; Wang, Shuxiang; Wang, Yajing; Cao, Zhijun; Li, Shengli

2018-06-10

Reducing dietary crude protein (CP) and supplementing with certain amino acids (AAs) has been known as a potential solution to improve nitrogen (N) efficiency in dairy production. Thus understanding how AAs are utilized in various sites along the gut is critical. AA flow from the intestine to portal-drained viscera (PDV) and liver then to the mammary gland was elaborated in this article. Recoveries in individual AA in PDV and liver seem to share similar AA pattern with input: output ratio in mammary gland, which subdivides essential AA (EAA) into two groups, lysine (Lys) and branched-chain AA (BCAA) in group 1, input: output ratio > 1; methionine (Met), histidine (His), phenylalanine (Phe) etc. in group 2, input: output ratio close to 1. AAs in the mammary gland are either utilized for milk protein synthesis or retained as body tissue, or catabolized. The fractional removal of AAs and the number and activity of AA transporters together contribute to the ability of AAs going through mammary cells. Mammalian target of rapamycin (mTOR) pathway is closely related to milk protein synthesis and provides alternatives for AA regulation of milk protein synthesis, which connects AA with lactose synthesis via α-lactalbumin (gene: LALBA) and links with milk fat synthesis via sterol regulatory element-binding transcription protein 1 (SREBP1) and peroxisome proliferator-activated receptor (PPAR). Overall, AA flow across various tissues reveal AA metabolism and utilization in dairy cows on one hand. While the function of AA in the biosynthesis of milk protein, fat and lactose at both transcriptional and posttranscriptional level from another angle provides the possibility for us to regulate them for higher efficiency. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.