Hypothalamic control of energy and glucose metabolism.

Science.gov (United States)

Sisley, Stephanie; Sandoval, Darleen

2011-09-01

The central nervous system (CNS), generally accepted to regulate energy homeostasis, has been implicated in the metabolic perturbations that either cause or are associated with obesity. Normally, the CNS receives hormonal, metabolic, and neuronal input to assure adequate energy levels and maintain stable energy homeostasis. Recent evidence also supports that the CNS uses these same inputs to regulate glucose homeostasis and this aspect of CNS regulation also becomes impaired in the face of dietary-induced obesity. This review focuses on the literature surrounding hypothalamic regulation of energy and glucose homeostasis and discusses how dysregulation of this system may contribute to obesity and T2DM.

Dynamics of final sectoral energy demand and aggregate energy intensity

International Nuclear Information System (INIS)

Lescaroux, Francois

2011-01-01

This paper proposes a regional and sectoral model of global final energy demand. For the main end-use sectors of consumption (industrial, commercial and public services, residential and road transportation), per-capita demand is expressed as an S-shaped function of per-capita income. Other variables intervene as well, like energy prices, temperatures and technological trends. This model is applied on a panel of 101 countries and 3 aggregates (covering the whole world) and it explains fairly well past variations in sectoral, final consumption since the beginning of the 2000s. Further, the model is used to analyze the dynamics of final energy demand, by sector and in total. The main conclusion concerns the pattern of change for aggregate energy intensity. The simulations performed show that there is no a priori reason for it to exhibit a bell-shape, as reported in the literature. Depending on initial conditions, the weight of basic needs in total consumption and the availability of modern commercial energy resources, various forms might emerge. - Research Highlights: → The residential sector accounts for most of final energy consumption at low income levels. → Its share drops at the benefit of the industrial, services and road transportation sectors in turn. → Sectoral shares' pattern is affected by changes in geographic, sociologic and economic factors. → Final energy intensity may show various shapes and does not exhibit necessarily a bell-shape.

Aspects of astrocyte energy metabolism, amino acid neurotransmitter homoeostasis and metabolic compartmentation

DEFF Research Database (Denmark)

Kreft, Marko; Bak, Lasse Kristoffer; Waagepetersen, Helle S

2012-01-01

Astrocytes are key players in brain function; they are intimately involved in neuronal signalling processes and their metabolism is tightly coupled to that of neurons. In the present review, we will be concerned with a discussion of aspects of astrocyte metabolism, including energy......-generating pathways and amino acid homoeostasis. A discussion of the impact that uptake of neurotransmitter glutamate may have on these pathways is included along with a section on metabolic compartmentation....

Weight Management, Energy Metabolism, and Endocrine Hor¬mones- Review Article

OpenAIRE

Seyed-Ali MOSTAFAVI; Saeed HOSSEINI

2015-01-01

Energy expenditure is determined by basal metabolic rate, physical activity, and Thermic Effect of Foods (TEF). Some endocrine hormones have role in basal metabolism and hence in human energy expenditure. And some foods pose more thermic effects on the total body energy expenditure and therefore can influence body weight. This review was performed to discuss factors which may affect body metabolism and body weight. Latest medical databases and nutrition and metabolism books were reviewed. We ...

VAPB/ALS8 MSP ligands regulate striated muscle energy metabolism critical for adult survival in caenorhabditis elegans.

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Sung Min Han

Full Text Available Mutations in VAPB/ALS8 are associated with amyotrophic lateral sclerosis (ALS and spinal muscular atrophy (SMA, two motor neuron diseases that often include alterations in energy metabolism. We have shown that C. elegans and Drosophila neurons secrete a cleavage product of VAPB, the N-terminal major sperm protein domain (vMSP. Secreted vMSPs signal through Roundabout and Lar-like receptors expressed on striated muscle. The muscle signaling pathway localizes mitochondria to myofilaments, alters their fission/fusion balance, and promotes energy production. Here, we show that neuronal loss of the C. elegans VAPB homolog triggers metabolic alterations that appear to compensate for muscle mitochondrial dysfunction. When vMSP levels drop, cytoskeletal or mitochondrial abnormalities in muscle induce elevated DAF-16, the Forkhead Box O (FoxO homolog, transcription factor activity. DAF-16 promotes muscle triacylglycerol accumulation, increases ATP levels in adults, and extends lifespan, despite reduced muscle mitochondria electron transport chain activity. Finally, Vapb knock-out mice exhibit abnormal muscular triacylglycerol levels and FoxO target gene transcriptional responses to fasting and refeeding. Our data indicate that impaired vMSP signaling to striated muscle alters FoxO activity, which affects energy metabolism. Abnormalities in energy metabolism of ALS patients may thus constitute a compensatory mechanism counterbalancing skeletal muscle mitochondrial dysfunction.

Construction and analysis of the model of energy metabolism in E. coli.

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Zixiang Xu

Full Text Available Genome-scale models of metabolism have only been analyzed with the constraint-based modelling philosophy and there have been several genome-scale gene-protein-reaction models. But research on the modelling for energy metabolism of organisms just began in recent years and research on metabolic weighted complex network are rare in literature. We have made three research based on the complete model of E. coli's energy metabolism. We first constructed a metabolic weighted network using the rates of free energy consumption within metabolic reactions as the weights. We then analyzed some structural characters of the metabolic weighted network that we constructed. We found that the distribution of the weight values was uneven, that most of the weight values were zero while reactions with abstract large weight values were rare and that the relationship between w (weight values and v (flux values was not of linear correlation. At last, we have done some research on the equilibrium of free energy for the energy metabolism system of E. coli. We found that E(out (free energy rate input from the environment can meet the demand of E(ch(in (free energy rate dissipated by chemical process and that chemical process plays a great role in the dissipation of free energy in cells. By these research and to a certain extend, we can understand more about the energy metabolism of E. coli.

Adipose tissue remodeling: its role in energy metabolism and metabolic disorders

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Sung Sik eChoe

2016-04-01

Full Text Available The adipose tissue is a central metabolic organ in the regulation of whole-body energy homeostasis. The white adipose tissue (WAT functions as a key energy reservoir for other organs, whereas the brown adipose tissue (BAT accumulates lipids for cold-induced adaptive thermogenesis. Adipose tissues secret various hormones, cytokines, and metabolites (termed as adipokines that control systemic energy balance by regulating appetitive signals from the central nerve system as well as metabolic activity in peripheral tissues. In response to changes in the nutritional status, the adipose tissue undergoes dynamic remodeling, including quantitative and qualitative alterations in adipose tissue resident cells. A growing body of evidence indicates that adipose tissue remodeling in obesity is closely associated with adipose tissue function. Changes in the number and size of the adipocytes affect the microenvironment of expanded fat tissues, accompanied by alterations in adipokine secretion, adipocyte death, local hypoxia, and fatty acid fluxes. Concurrently, stromal vascular cells in the adipose tissue, including immune cells, are involved in numerous adaptive processes, such as dead adipocyte clearance, adipogenesis, and angiogenesis, all of which are dysregulated in obese adipose tissue remodeling. Chronic over-nutrition triggers uncontrolled inflammatory responses, leading to systemic low-grade inflammation and metabolic disorders, such as insulin resistance. This review will discuss current mechanistic understandings of adipose tissue remodeling processes in adaptive energy homeostasis and pathological remodeling of adipose tissue in connection with immune response.

Metabolic regulation of neuronal plasticity by the energy sensor AMPK.

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Wyatt B Potter

Full Text Available Long Term Potentiation (LTP is a leading candidate mechanism for learning and memory and is also thought to play a role in the progression of seizures to intractable epilepsy. Maintenance of LTP requires RNA transcription, protein translation and signaling through the mammalian Target of Rapamycin (mTOR pathway. In peripheral tissue, the energy sensor AMP-activated Protein Kinase (AMPK negatively regulates the mTOR cascade upon glycolytic inhibition and cellular energy stress. We recently demonstrated that the glycolytic inhibitor 2-deoxy-D-glucose (2DG alters plasticity to retard epileptogenesis in the kindling model of epilepsy. Reduced kindling progression was associated with increased recruitment of the nuclear metabolic sensor CtBP to NRSF at the BDNF promoter. Given that energy metabolism controls mTOR through AMPK in peripheral tissue and the role of mTOR in LTP in neurons, we asked whether energy metabolism and AMPK control LTP. Using a combination of biochemical approaches and field-recordings in mouse hippocampal slices, we show that the master regulator of energy homeostasis, AMPK couples energy metabolism to LTP expression. Administration of the glycolytic inhibitor 2-deoxy-D-glucose (2DG or the mitochondrial toxin and anti-Type II Diabetes drug, metformin, or AMP mimetic AICAR results in activation of AMPK, repression of the mTOR pathway and prevents maintenance of Late-Phase LTP (L-LTP. Inhibition of AMPK by either compound-C or the ATP mimetic ara-A rescues the suppression of L-LTP by energy stress. We also show that enhanced LTP via AMPK inhibition requires mTOR signaling. These results directly link energy metabolism to plasticity in the mammalian brain and demonstrate that AMPK is a modulator of LTP. Our work opens up the possibility of using modulators of energy metabolism to control neuronal plasticity in diseases and conditions of aberrant plasticity such as epilepsy.

Timing of potential and metabolic brain energy

DEFF Research Database (Denmark)

Korf, Jakob; Gramsbergen, Jan Bert

2007-01-01

functions. We introduce the concepts of potential and metabolic brain energy to distinguish trans-membrane gradients of ions or neurotransmitters and the capacity to generate energy from intra- or extra-cerebral substrates, respectively. Higher brain functions, such as memory retrieval, speaking......The temporal relationship between cerebral electro-physiological activities, higher brain functions and brain energy metabolism is reviewed. The duration of action potentials and transmission through glutamate and GABA are most often less than 5 ms. Subjects may perform complex psycho......-physiological tasks within 50 to 200 ms, and perception of conscious experience requires 0.5 to 2 s. Activation of cerebral oxygen consumption starts after at least 100 ms and increases of local blood flow become maximal after about 1 s. Current imaging technologies are unable to detect rapid physiological brain...

Energy metabolism in astrocytes and neurons treated with manganese: relation among cell-specific energy failure, glucose metabolism, and intercellular trafficking using multinuclear NMR-spectroscopic analysis.

Science.gov (United States)

Zwingmann, Claudia; Leibfritz, Dieter; Hazell, Alan S

2003-06-01

A central question in manganese neurotoxicity concerns mitochondrial dysfunction leading to cerebral energy failure. To obtain insight into the underlying mechanism(s), the authors investigated cell-specific pathways of [1-13C]glucose metabolism by high-resolution multinuclear NMR-spectroscopy. Five-day treatment of neurons with 100-micro mol/L MnCl(2) led to 50% and 70% decreases of ATP/ADP and phosphocreatine-creatine ratios, respectively. An impaired flux of [1-13C]glucose through pyruvate dehydrogenase, which was associated with Krebs cycle inhibition and hence depletion of [4-13C]glutamate, [2-13C]GABA, and [13C]glutathione, hindered the ability of neurons to compensate for mitochondrial dysfunction by oxidative glucose metabolism and further aggravated neuronal energy failure. Stimulated glycolysis and oxidative glucose metabolism protected astrocytes against energy failure and oxidative stress, leading to twofold increased de novo synthesis of [3-13C]lactate and fourfold elevated [4-13C]glutamate and [13C]glutathione levels. Manganese, however, inhibited the synthesis and release of glutamine. Comparative NMR data obtained from cocultures showed disturbed astrocytic function and a failure of astrocytes to provide neurons with substrates for energy and neurotransmitter metabolism, leading to deterioration of neuronal antioxidant capacity (decreased glutathione levels) and energy metabolism. The results suggest that, concomitant to impaired neuronal glucose oxidation, changes in astrocytic metabolism may cause a loss of intercellular homeostatic equilibrium, contributing to neuronal dysfunction in manganese neurotoxicity.

Tributyltin disrupts feeding and energy metabolism in the goldfish (Carassius auratus).

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Zhang, Jiliang; Sun, Ping; Yang, Fan; Kong, Tao; Zhang, Ruichen

2016-06-01

Tributyltin (TBT) can induce obesogen response. However, little is known about the adverse effects of TBT on food intake and energy metabolism. The present study was designed to investigate the effects of TBT, at environmental concentrations of 2.44 and 24.4 ng/L (1 and 10 ng/L as Sn), on feeding and energy metabolism in goldfish (Carassius auratus). After exposure for 54 d, TBT increased the weight gain and food intake in fish. The patterns of brain neuropeptide genes expression were in line with potential orexigenic effects, with increased expression of neuropeptide Y and apelin, and decreased expression of pro-opiomelanocortin, ghrelin, cocaine and amphetamine-regulated transcript, and corticotropin-releasing factor. Interestingly, the energy metabolism indicators (oxygen consumption, ammonia exertion and swimming activity) and the serum thyroid hormones were all significantly increased at the 2.44 ng/L TBT group in fish. However, no changes of energy metabolism indicators or a decrease of thyroid hormones was found at the 24.4 ng/L TBT group, which indicated a complex disrupting effect on metabolism of TBT. In short, TBT can alter feeding and energy metabolism in fish, which might promote the obesogenic responses. Copyright © 2016 Elsevier Ltd. All rights reserved.

Energy metabolism and nutritional status in hospitalized patients with lung cancer.

Science.gov (United States)

Takemura, Yumi; Sasaki, Masaya; Goto, Kenichi; Takaoka, Azusa; Ohi, Akiko; Kurihara, Mika; Nakanishi, Naoko; Nakano, Yasutaka; Hanaoka, Jun

2016-09-01

This study aimed to investigate the energy metabolism of patients with lung cancer and the relationship between energy metabolism and proinflammatory cytokines. Twenty-eight patients with lung cancer and 18 healthy controls were enrolled in this study. The nutritional status upon admission was analyzed using nutritional screening tools and laboratory tests. The resting energy expenditure and respiratory quotient were measured using indirect calorimetry, and the predicted resting energy expenditure was calculated using the Harris-Benedict equation. Energy expenditure was increased in patients with advanced stage disease, and there were positive correlations between measured resting energy expenditure/body weight and interleukin-6 levels and between measured resting energy expenditure/predicted resting energy expenditure and interleukin-6 levels. There were significant relationships between body mass index and plasma leptin or acylated ghrelin levels. However, the level of appetite controlling hormones did not affect dietary intake. There was a negative correlation between plasma interleukin-6 levels and dietary intake, suggesting that interleukin-6 plays a role in reducing dietary intake. These results indicate that energy expenditure changes significantly with lung cancer stage and that plasma interleukin-6 levels affect energy metabolism and dietary intake. Thus, nutritional management that considers the changes in energy metabolism is important in patients with lung cancer.

Validated Predictions of Metabolic Energy Consumption for Submaximal Effort Movement

OpenAIRE

Tsianos, George A.; MacFadden, Lisa N.

2016-01-01

Author Summary Muscles consume metabolic energy to generate movement. Performing a movement over a long period of time or at a high intensity strains the respiratory and cardiovascular systems that need to replenish the energy reserves in muscle. Furthermore, consuming and replenishing metabolic energy involves biochemical reactions with byproducts that cause muscle fatigue. These biochemical reactions also produce heat that increases body temperature, potentially causing central fatigue. A m...

Adaptive evolution of mitochondrial energy metabolism genes associated with increased energy demand in flying insects.

Science.gov (United States)

Yang, Yunxia; Xu, Shixia; Xu, Junxiao; Guo, Yan; Yang, Guang

2014-01-01

Insects are unique among invertebrates for their ability to fly, which raises intriguing questions about how energy metabolism in insects evolved and changed along with flight. Although physiological studies indicated that energy consumption differs between flying and non-flying insects, the evolution of molecular energy metabolism mechanisms in insects remains largely unexplored. Considering that about 95% of adenosine triphosphate (ATP) is supplied by mitochondria via oxidative phosphorylation, we examined 13 mitochondrial protein-encoding genes to test whether adaptive evolution of energy metabolism-related genes occurred in insects. The analyses demonstrated that mitochondrial DNA protein-encoding genes are subject to positive selection from the last common ancestor of Pterygota, which evolved primitive flight ability. Positive selection was also found in insects with flight ability, whereas no significant sign of selection was found in flightless insects where the wings had degenerated. In addition, significant positive selection was also identified in the last common ancestor of Neoptera, which changed its flight mode from direct to indirect. Interestingly, detection of more positively selected genes in indirect flight rather than direct flight insects suggested a stronger selective pressure in insects having higher energy consumption. In conclusion, mitochondrial protein-encoding genes involved in energy metabolism were targets of adaptive evolution in response to increased energy demands that arose during the evolution of flight ability in insects.

High energy diets-induced metabolic and prediabetic painful polyneuropathy in rats.

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Fang Xie

Full Text Available To establish the role of the metabolic state in the pathogenesis of polyneuropathy, an age- and sex-matched, longitudinal study in rats fed high-fat and high-sucrose diets (HFSD or high-fat, high-sucrose and high-salt diets (HFSSD relative to controls was performed. Time courses of body weight, systolic blood pressure, fasting plasma glucose (FPG, insulin, free fatty acids (FFA, homeostasis model assessment-insulin resistance index (HOMA-IR, thermal and mechanical sensitivity and motor coordination were measured in parallel. Finally, large and small myelinated fibers (LMF, SMF as well as unmyelinated fibers (UMF in the sciatic nerves and ascending fibers in the spinal dorsal column were quantitatively assessed under electron microscopy. The results showed that early metabolic syndrome (hyperinsulinemia, dyslipidemia, and hypertension and prediabetic conditions (impaired fasting glucose could be induced by high energy diet, and these animals later developed painful polyneuropathy characterized by myelin breakdown and LMF loss in both peripheral and central nervous system. In contrast SMF and UMF in the sciatic nerves were changed little, in the same animals. Therefore the phenomenon that high energy diets induce bilateral mechanical, but not thermal, pain hypersensitivity is reflected by severe damage to LMF, but mild damage to SMF and UMF. Moreover, dietary sodium (high-salt deteriorates the neuropathic pathological process induced by high energy diets, but paradoxically high salt consumption, may reduce, at least temporarily, chronic pain perception in these animals.

High Energy Diets-Induced Metabolic and Prediabetic Painful Polyneuropathy in Rats

Science.gov (United States)

Hou, Jun-Feng; Jiao, Kai; Costigan, Michael; Chen, Jun

2013-01-01

To establish the role of the metabolic state in the pathogenesis of polyneuropathy, an age- and sex-matched, longitudinal study in rats fed high-fat and high-sucrose diets (HFSD) or high-fat, high-sucrose and high-salt diets (HFSSD) relative to controls was performed. Time courses of body weight, systolic blood pressure, fasting plasma glucose (FPG), insulin, free fatty acids (FFA), homeostasis model assessment-insulin resistance index (HOMA-IR), thermal and mechanical sensitivity and motor coordination were measured in parallel. Finally, large and small myelinated fibers (LMF, SMF) as well as unmyelinated fibers (UMF) in the sciatic nerves and ascending fibers in the spinal dorsal column were quantitatively assessed under electron microscopy. The results showed that early metabolic syndrome (hyperinsulinemia, dyslipidemia, and hypertension) and prediabetic conditions (impaired fasting glucose) could be induced by high energy diet, and these animals later developed painful polyneuropathy characterized by myelin breakdown and LMF loss in both peripheral and central nervous system. In contrast SMF and UMF in the sciatic nerves were changed little, in the same animals. Therefore the phenomenon that high energy diets induce bilateral mechanical, but not thermal, pain hypersensitivity is reflected by severe damage to LMF, but mild damage to SMF and UMF. Moreover, dietary sodium (high-salt) deteriorates the neuropathic pathological process induced by high energy diets, but paradoxically high salt consumption, may reduce, at least temporarily, chronic pain perception in these animals. PMID:23451227

Environmental effects on energy metabolism and 86Rb elimination rates of fishes

International Nuclear Information System (INIS)

Peters, E.L.

1994-01-01

Relationships between energy metabolism and the turnover rates of number of important chemical and radiological elements (particularly the Group IA alkali metals: K, Rb, and Cs) have been observed in fishes. Using response surface statistics and fractional factorial ANOVA, the author examined the relative influences of temperature, salinity, food intake rate, mass, and their first order interactions on routine energy metabolism and 86 Rb elimination rates. Routine metabolic rates were increased primarily by increased temperature and salinity, with a strong body mass effect and a significant effect of food intake. 86 Rb elimination rates were increased primarily by increased temperature and salinity. There were no interactive effects between mass and either temperature or salinity for either routine energy metabolism or 86 Rb elimination rates. There was a significant interaction effect between temperature and salinity on routine energy metabolism rates, but not on 86 Rb elimination. The authors also observed a relationship between routine energy metabolism and 86 Rb elimination rates that may possibly be exploited as a means of estimating energy metabolic rates of fishes in the field. The statistical techniques used in this experiment have broad potential applications in assessing the contributions of combinations of environmental variables on contaminant kinetics, as well as in multiple toxicity testing, in that they greatly simplify experimental designs compared with traditional full-factorial methods

Islet transplantation in diabetic rats normalizes basal and exercise-induced energy metabolism

NARCIS (Netherlands)

Houwing, Harmina; Benthem, L.; Suylichem, P.T.R. van; Leest, J. van der; Strubbe, J.H.; Steffens, A.B.

Transplantation of islets of Langerhans in diabetic rats normalizes resting glucose and insulin levels, but it remains unclear whether islet transplantation restores resting and exercise-induced energy metabolism. Therefore, we compared energy metabolism in islet transplanted rats with energy

Final Energy Consumption Trends and Drivers in Czech Republic and Latvia

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Zhiqian Yu

2017-08-01

Full Text Available This paper analyses the trends of final energy consumption in Latvia and Czech Republic. Analysis of final energy consumption during 2000-2013 period indicated the main driving forces of final energy consumption during and after world financial crisis of 2008. The paper aimed to evaluate the impact of economic activity and other factors on final energy consumption. The decomposition of the final energy consumption is assessed by analyzing effect of different drivers by the main end-users sector (industry, transport, households, agriculture, services, activity, demography, lifestyles, structural effects, energy savings etc. The results show that the reduction in final energy consumption in most EU members states before and after year 2008 can be related to the decline in energy intensities within endusers sectors. At the same time, the increase in final energy intensity after the year 2008 is attributed to expansion of energy demand sectors. Comparison of final energy consumption trends and drivers in Latvia and Czech Republic indicated that Czech Republic implemented more policies and measures in industry and tertiary sector and this provided for final energy consumption decreased and huge energy savings in these sectors.

Simulating antler growth and energy, nitrogen, calcium and phosphorus metabolism in caribou

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Ron Moen

1998-03-01

Full Text Available We added antler growth and mineral metabolism modules to a previously developed energetics model for ruminants to simulate energy and mineral balance of male and female caribou throughout an annual cycle. Body watet, fat, protein, and ash are monitored on a daily time step, and energy costs associated with reproduction and body mass changes are simulated. In order to simulate antler growth, we had to predict calcium and phosphorus metabolism as it is affected by antler growth, gestation, and lactation. We used data on dietary digestibility, protein, calcium and phosphorus content, and seasonal patterns in body mass to predict the energy, nitrogen, calcium, and phosphorus balances of a "generic" male and female caribou. Antler growth in males increased energy requirements during antler growth by 8 to 16%, depending on the efficiency with which energy was used for antler growth. Female energy requirements for antler growth were proportionately much smaller because of the smaller size of female antlers. Protein requirements for antler growth in both males and females were met by forage intake. Calcium and phosphorus must be resorbed from bone during peak antler growth in males, when > 25 g/day of calcium and > 12 g/day of phosphorus are being deposited in antlers. Females are capable of meeting calcium needs during antler growth without bone resorption, but phosphorus was resorbed from bone during the final stages of antler mineralization. After energy, phosphorus was most likely to limit growth of antlers for both males and females in our simulations. Input parameters can be easily changed to represent caribou from specific geographic regions in which dietary nutrient content or body mass patterns differ from those in our "generic" caribou. The model can be used to quantitatively analyze the evolutionary basis for development of antlers in female caribou, and the relationship between body mass and antler size in the Cervidae.

Hypothalamic carnitine metabolism integrates nutrient and hormonal feedback to regulate energy homeostasis.

Science.gov (United States)

Stark, Romana; Reichenbach, Alex; Andrews, Zane B

2015-12-15

The maintenance of energy homeostasis requires the hypothalamic integration of nutrient feedback cues, such as glucose, fatty acids, amino acids, and metabolic hormones such as insulin, leptin and ghrelin. Although hypothalamic neurons are critical to maintain energy homeostasis research efforts have focused on feedback mechanisms in isolation, such as glucose alone, fatty acids alone or single hormones. However this seems rather too simplistic considering the range of nutrient and endocrine changes associated with different metabolic states, such as starvation (negative energy balance) or diet-induced obesity (positive energy balance). In order to understand how neurons integrate multiple nutrient or hormonal signals, we need to identify and examine potential intracellular convergence points or common molecular targets that have the ability to sense glucose, fatty acids, amino acids and hormones. In this review, we focus on the role of carnitine metabolism in neurons regulating energy homeostasis. Hypothalamic carnitine metabolism represents a novel means for neurons to facilitate and control both nutrient and hormonal feedback. In terms of nutrient regulation, carnitine metabolism regulates hypothalamic fatty acid sensing through the actions of CPT1 and has an underappreciated role in glucose sensing since carnitine metabolism also buffers mitochondrial matrix levels of acetyl-CoA, an allosteric inhibitor of pyruvate dehydrogenase and hence glucose metabolism. Studies also show that hypothalamic CPT1 activity also controls hormonal feedback. We hypothesis that hypothalamic carnitine metabolism represents a key molecular target that can concurrently integrate nutrient and hormonal information, which is critical to maintain energy homeostasis. We also suggest this is relevant to broader neuroendocrine research as it predicts that hormonal signaling in the brain varies depending on current nutrient status. Indeed, the metabolic action of ghrelin, leptin or insulin

Regional final energy consumptions

International Nuclear Information System (INIS)

2011-01-01

This report comments the differences observed between the French regions and also between these regions and national data in terms of final energy consumption per inhabitant, per GDP unit, and per sector (housing and office building, transport, industry, agriculture). It also comments the evolutions during the last decades, identifies the most recent trends

Fatty acids in energy metabolism of the central nervous system.

Science.gov (United States)

Panov, Alexander; Orynbayeva, Zulfiya; Vavilin, Valentin; Lyakhovich, Vyacheslav

2014-01-01

In this review, we analyze the current hypotheses regarding energy metabolism in the neurons and astroglia. Recently, it was shown that up to 20% of the total brain's energy is provided by mitochondrial oxidation of fatty acids. However, the existing hypotheses consider glucose, or its derivative lactate, as the only main energy substrate for the brain. Astroglia metabolically supports the neurons by providing lactate as a substrate for neuronal mitochondria. In addition, a significant amount of neuromediators, glutamate and GABA, is transported into neurons and also serves as substrates for mitochondria. Thus, neuronal mitochondria may simultaneously oxidize several substrates. Astrocytes have to replenish the pool of neuromediators by synthesis de novo, which requires large amounts of energy. In this review, we made an attempt to reconcile β-oxidation of fatty acids by astrocytic mitochondria with the existing hypothesis on regulation of aerobic glycolysis. We suggest that, under condition of neuronal excitation, both metabolic pathways may exist simultaneously. We provide experimental evidence that isolated neuronal mitochondria may oxidize palmitoyl carnitine in the presence of other mitochondrial substrates. We also suggest that variations in the brain mitochondrial metabolic phenotype may be associated with different mtDNA haplogroups.

Final Energy Consumption Trends and Drivers in Czech Republic and Latvia

OpenAIRE

Zhiqian Yu; Dalia Streimikiene; Tomas Balezentis; Rimantas Dapkus; Radislav Jovovic; Veselin Draskovic

2017-01-01

This paper analyses the trends of final energy consumption in Latvia and Czech Republic. Analysis of final energy consumption during 2000-2013 period indicated the main driving forces of final energy consumption during and after world financial crisis of 2008. The paper aimed to evaluate the impact of economic activity and other factors on final energy consumption. The decomposition of the final energy consumption is assessed by analyzing effect of different drivers by the main end-users sect...

Lactate rescues neuronal sodium homeostasis during impaired energy metabolism

OpenAIRE

Karus, Claudia; Ziemens, Daniel; Rose, Christine R

2015-01-01

Recently, we established that recurrent activity evokes network sodium oscillations in neurons and astrocytes in hippocampal tissue slices. Interestingly, metabolic integrity of astrocytes was essential for the neurons' capacity to maintain low sodium and to recover from sodium loads, indicating an intimate metabolic coupling between the 2 cell types. Here, we studied if lactate can support neuronal sodium homeostasis during impaired energy metabolism by analyzing whether glucose removal, pha...

Ontogeny of hepatic energy metabolism genes in mice as revealed by RNA-sequencing.

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Helen J Renaud

Full Text Available The liver plays a central role in metabolic homeostasis by coordinating synthesis, storage, breakdown, and redistribution of nutrients. Hepatic energy metabolism is dynamically regulated throughout different life stages due to different demands for energy during growth and development. However, changes in gene expression patterns throughout ontogeny for factors important in hepatic energy metabolism are not well understood. We performed detailed transcript analysis of energy metabolism genes during various stages of liver development in mice. Livers from male C57BL/6J mice were collected at twelve ages, including perinatal and postnatal time points (n = 3/age. The mRNA was quantified by RNA-Sequencing, with transcript abundance estimated by Cufflinks. One thousand sixty energy metabolism genes were examined; 794 were above detection, of which 627 were significantly changed during at least one developmental age compared to adult liver. Two-way hierarchical clustering revealed three major clusters dependent on age: GD17.5-Day 5 (perinatal-enriched, Day 10-Day 20 (pre-weaning-enriched, and Day 25-Day 60 (adolescence/adulthood-enriched. Clustering analysis of cumulative mRNA expression values for individual pathways of energy metabolism revealed three patterns of enrichment: glycolysis, ketogenesis, and glycogenesis were all perinatally-enriched; glycogenolysis was the only pathway enriched during pre-weaning ages; whereas lipid droplet metabolism, cholesterol and bile acid metabolism, gluconeogenesis, and lipid metabolism were all enriched in adolescence/adulthood. This study reveals novel findings such as the divergent expression of the fatty acid β-oxidation enzymes Acyl-CoA oxidase 1 and Carnitine palmitoyltransferase 1a, indicating a switch from mitochondrial to peroxisomal β-oxidation after weaning; as well as the dynamic ontogeny of genes implicated in obesity such as Stearoyl-CoA desaturase 1 and Elongation of very long chain fatty

Thermodynamics of the living organisms. Allometric relationship between the total metabolic energy, chemical energy and body temperature in mammals

Science.gov (United States)

Atanasov, Atanas Todorov

2017-11-01

The study present relationship between the total metabolic energy (ETME(c), J) derived as a function of body chemical energy (Gchem, J) and absolute temperature (Tb, K) in mammals: ETME(c) =Gchem (Tb/Tn). In formula the temperature Tn =2.73K appears normalization temperature. The calculated total metabolic energy ETME(c) differs negligible from the total metabolic energy ETME(J), received as a product between the basal metabolic rate (Pm, J/s) and the lifespan (Tls, s) of mammals: ETME = Pm×Tls. The physical nature and biological mean of the normalization temperature (Tn, K) is unclear. It is made the hypothesis that the kTn energy (where k= 1.3806×10-23 J/K -Boltzmann constant) presents energy of excitation states (modes) in biomolecules and body structures that could be in equilibrium with chemical energy accumulated in body. This means that the accumulated chemical energy allows trough all body molecules and structures to propagate excitations states with kTn energy with wavelength in the rage of width of biological membranes. The accumulated in biomolecules chemical energy maintains spread of the excited states through biomolecules without loss of energy.

Brain Ceramide Metabolism in the Control of Energy Balance

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Céline Cruciani-Guglielmacci

2017-10-01

Full Text Available The regulation of energy balance by the central nervous system (CNS is a key actor of energy homeostasis in mammals, and deregulations of the fine mechanisms of nutrient sensing in the brain could lead to several metabolic diseases such as obesity and type 2 diabetes (T2D. Indeed, while neuronal activity primarily relies on glucose (lactate, pyruvate, the brain expresses at high level enzymes responsible for the transport, utilization and storage of lipids. It has been demonstrated that discrete neuronal networks in the hypothalamus have the ability to detect variation of circulating long chain fatty acids (FA to regulate food intake and peripheral glucose metabolism. During a chronic lipid excess situation, this physiological lipid sensing is impaired contributing to type 2 diabetes in predisposed subjects. Recently, different studies suggested that ceramides levels could be involved in the regulation of energy balance in both hypothalamic and extra-hypothalamic areas. Moreover, under lipotoxic conditions, these ceramides could play a role in the dysregulation of glucose homeostasis. In this review we aimed at describing the potential role of ceramides metabolism in the brain in the physiological and pathophysiological control of energy balance.

Anaerobic energy metabolism in unicellular photosynthetic eukaryotes.

Science.gov (United States)

Atteia, Ariane; van Lis, Robert; Tielens, Aloysius G M; Martin, William F

2013-02-01

Anaerobic metabolic pathways allow unicellular organisms to tolerate or colonize anoxic environments. Over the past ten years, genome sequencing projects have brought a new light on the extent of anaerobic metabolism in eukaryotes. A surprising development has been that free-living unicellular algae capable of photoautotrophic lifestyle are, in terms of their enzymatic repertoire, among the best equipped eukaryotes known when it comes to anaerobic energy metabolism. Some of these algae are marine organisms, common in the oceans, others are more typically soil inhabitants. All these species are important from the ecological (O(2)/CO(2) budget), biotechnological, and evolutionary perspectives. In the unicellular algae surveyed here, mixed-acid type fermentations are widespread while anaerobic respiration, which is more typical of eukaryotic heterotrophs, appears to be rare. The presence of a core anaerobic metabolism among the algae provides insights into its evolutionary origin, which traces to the eukaryote common ancestor. The predicted fermentative enzymes often exhibit an amino acid extension at the N-terminus, suggesting that these proteins might be compartmentalized in the cell, likely in the chloroplast or the mitochondrion. The green algae Chlamydomonas reinhardtii and Chlorella NC64 have the most extended set of fermentative enzymes reported so far. Among the eukaryotes with secondary plastids, the diatom Thalassiosira pseudonana has the most pronounced anaerobic capabilities as yet. From the standpoints of genomic, transcriptomic, and biochemical studies, anaerobic energy metabolism in C. reinhardtii remains the best characterized among photosynthetic protists. This article is part of a Special Issue entitled: The evolutionary aspects of bioenergetic systems. Copyright © 2012 Elsevier B.V. All rights reserved.

Emerging role of the brain in the homeostatic regulation of energy and glucose metabolism.

Science.gov (United States)

Roh, Eun; Song, Do Kyeong; Kim, Min-Seon

2016-03-11

Accumulated evidence from genetic animal models suggests that the brain, particularly the hypothalamus, has a key role in the homeostatic regulation of energy and glucose metabolism. The brain integrates multiple metabolic inputs from the periphery through nutrients, gut-derived satiety signals and adiposity-related hormones. The brain modulates various aspects of metabolism, such as food intake, energy expenditure, insulin secretion, hepatic glucose production and glucose/fatty acid metabolism in adipose tissue and skeletal muscle. Highly coordinated interactions between the brain and peripheral metabolic organs are critical for the maintenance of energy and glucose homeostasis. Defective crosstalk between the brain and peripheral organs contributes to the development of obesity and type 2 diabetes. Here we comprehensively review the above topics, discussing the main findings related to the role of the brain in the homeostatic regulation of energy and glucose metabolism.

Ammonia-induced energy disorders interfere with bilirubin metabolism in hepatocytes.

Science.gov (United States)

Wang, Qiongye; Wang, Yanfang; Yu, Zujiang; Li, Duolu; Jia, Bin; Li, Jingjing; Guan, Kelei; Zhou, Yubing; Chen, Yanling; Kan, Quancheng

2014-08-01

Hyperammonemia and jaundice are the most common clinical symptoms of hepatic failure. Decreasing the level of ammonia in the blood is often accompanied by a reduction in bilirubin in patients with hepatic failure. Previous studies have shown that hyperammonemia can cause bilirubin metabolism disorders, however it is unclear exactly how hyperammonemia interferes with bilirubin metabolism in hepatocytes. The purpose of the current study was to determine the mechanism or mechanisms by which hyperammonemia interferes with bilirubin metabolism in hepatocytes. Cell viability and apoptosis were analyzed in primary hepatocytes that had been exposed to ammonium chloride. Mitochondrial morphology and permeability were observed and analyzed, intermediates of the tricarboxylic acid (TCA) cycle were determined and changes in the expression of enzymes related to bilirubin metabolism were analyzed after ammonia exposure. Hyperammonemia inhibited cell growth, induced apoptosis, damaged the mitochondria and hindered the TCA cycle in hepatocytes. This led to a reduction in energy synthesis, eventually affecting the expression of enzymes related to bilirubin metabolism, which then caused further problems with bilirubin metabolism. These effects were significant, but could be reversed with the addition of adenosine triphosphate (ATP). This study demonstrates that ammonia can cause problems with bilirubin metabolism by interfering with energy synthesis. Copyright © 2014 Elsevier Inc. All rights reserved.

Effect of hemoglobin and immunization status on energy metabolism of weanling pigs.

Science.gov (United States)

Gentry, J L; Swinkels, J W; Lindemann, M D; Schrama, J W

1997-04-01

We investigated the effect of (Hb) and immunization status on energy metabolism of newly weaned pigs. An additional focus of the study was to determine the development of circadian rhythms as evidenced by heat production patterns. Twenty-four 4-wk-old crossbred weanling barrows were placed into groups of three based on weight and litter origin, and the groups were allotted to one of four treatments. Treatments were arranged as a 2 x 2 factorial. The factors included 1) Hb status (low vs high) and 2) immunization status (antigen vs placebo). Hemoglobin status was obtained by injecting 3-d-old barrows with 100 (low) or 200 mg (high) of Fe. At 4 wk, initial blood Hb concentrations were 6.0 mM for the low group and 7.8 mM for the high group. Energy metabolism was measured using two weekly total energy and nitrogen balance collections. Energy intake and retention were higher (P Energy metabolism was not affected (P > .10) by immunization status, and heat production was not affected (P > .10) by either Hb or immunization status. Total heat production (HTOT) increased (P light period compared with the dark period over the total experimental period but a decrease (P dark period was approximately half of that measured during the light period. In conclusion, Hb status affected energy metabolism; pigs having a high Hb status had a higher energy retention. Immunization status had minimal effects on energy metabolism and heat production. Additionally, the diurnal circadian rhythm seen in older pigs had not been established by 2 wk after weaning.

Mechanistic modeling of aberrant energy metabolism in human disease

Directory of Open Access Journals (Sweden)

Vineet eSangar

2012-10-01

Full Text Available Dysfunction in energy metabolism—including in pathways localized to the mitochondria—has been implicated in the pathogenesis of a wide array of disorders, ranging from cancer to neurodegenerative diseases to type II diabetes. The inherent complexities of energy and mitochondrial metabolism present a significant obstacle in the effort to understand the role that these molecular processes play in the development of disease. To help unravel these complexities, systems biology methods have been applied to develop an array of computational metabolic models, ranging from mitochondria-specific processes to genome-scale cellular networks. These constraint-based models can efficiently simulate aspects of normal and aberrant metabolism in various genetic and environmental conditions. Development of these models leverages—and also provides a powerful means to integrate and interpret—information from a wide range of sources including genomics, proteomics, metabolomics, and enzyme kinetics. Here, we review a variety of mechanistic modeling studies that explore metabolic functions, deficiency disorders, and aberrant biochemical pathways in mitochondria and related regions in the cell.

Regulation - renewable energies finally liberated?

International Nuclear Information System (INIS)

Blosseville, Thomas

2016-01-01

Within the context defined by the new French policy for energy transition, notably in terms of share of renewable energies in final energy consumption, France seems to be somehow late in the development of these energies: about 1 GW of wind energy are installed each year when the expected pace would be 1,5 GW, and the photovoltaic market is shrinking. As the legal context is important, this article proposes an overview of the evolution of the French policy during the last four years which started with interesting measures. Recently, the government showed its will to liberate renewable energies from several constraints. Some legal procedures tend to slow down the development. Some advances could therefore be made, for example to make rules less complex and numerous. The different situations of the wind and biogas sectors are evoked, as well as new opportunities created by a new decree on investment planning

Energy requirements, protein-energy metabolism and balance, and carbohydrates in preterm infants.

Science.gov (United States)

Hay, William W; Brown, Laura D; Denne, Scott C

2014-01-01

Energy is necessary for all vital functions of the body at molecular, cellular, organ, and systemic levels. Preterm infants have minimum energy requirements for basal metabolism and growth, but also have requirements for unique physiology and metabolism that influence energy expenditure. These include body size, postnatal age, physical activity, dietary intake, environmental temperatures, energy losses in the stool and urine, and clinical conditions and diseases, as well as changes in body composition. Both energy and protein are necessary to produce normal rates of growth. Carbohydrates (primarily glucose) are principle sources of energy for the brain and heart until lipid oxidation develops over several days to weeks after birth. A higher protein/energy ratio is necessary in most preterm infants to approximate normal intrauterine growth rates. Lean tissue is predominantly produced during early gestation, which continues through to term. During later gestation, fat accretion in adipose tissue adds increasingly large caloric requirements to the lean tissue growth. Once protein intake is sufficient to promote net lean body accretion, additional energy primarily produces more body fat, which increases almost linearly at energy intakes >80-90 kcal/kg/day in normal, healthy preterm infants. Rapid gains in adiposity have the potential to produce later life obesity, an increasingly recognized risk of excessive energy intake. In addition to fundamental requirements for glucose, protein, and fat, a variety of non-glucose carbohydrates found in human milk may have important roles in promoting growth and development, as well as production of a gut microbiome that could protect against necrotizing enterocolitis. © 2014 S. Karger AG, Basel.

Adaptations of energy metabolism during cerebellar neurogenesis are co-opted in medulloblastoma.

Science.gov (United States)

Tech, Katherine; Deshmukh, Mohanish; Gershon, Timothy R

2015-01-28

Recent studies show that metabolic patterns typical of cancer cells, including aerobic glycolysis and increased lipogenesis, are not unique to malignancy, but rather originate in physiologic development. In the postnatal brain, where sufficient oxygen for energy metabolism is scrupulously maintained, neural progenitors nevertheless metabolize glucose to lactate and prioritize lipid synthesis over fatty acid oxidation. Medulloblastoma, a cancer of neural progenitors that is the most common malignant brain tumor in children, recapitulates the metabolic phenotype of brain progenitor cells. During the physiologic proliferation of neural progenitors, metabolic enzymes generally associated with malignancy, including Hexokinase 2 (Hk2) and Pyruvate kinase M2 (PkM2) configure energy metabolism to support growth. In these non-malignant cells, expression of Hk2 and PkM2 is driven by transcriptional regulators that are typically identified as oncogenes, including N-myc. Importantly, N-myc continues to drive Hk2 and PkM2 in medulloblastoma. Similarly E2F transcription factors and PPARγ function in both progenitors and medulloblastoma to optimize energy metabolism to support proliferation. These findings show that the "metabolic transformation" that is a hallmark of cancer is not specifically limited to cancer. Rather, metabolic transformation represents a co-opting of developmental programs integral to physiologic growth. Despite their physiologic origins, the molecular mechanisms that mediate metabolic transformation may nevertheless present ideal targets for novel anti-tumor therapy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

[Modifications in myocardial energy metabolism in diabetic patients

Science.gov (United States)

Grynberg, A

2001-11-01

The capacity of cardiac myocyte to regulate ATP production to face any change in energy demand is a major determinant of cardiac function. Because FA is the main heart fuel (although the most expensive one in oxygen, and prompt to induce deleterious effects), this process is based on a balanced fatty acid (FA) metabolism. Several pathological situations are associated with an accumulation of FA or derivatives, or with an excessive b-oxidation. The diabetic cardiomyocyte is characterised by an over consumption of FA. The control of the FA/glucose balance clearly appears as a new strategy for cytoprotection, particularly in diabetes and requires a reduced FA contribution to ATP production. Cardiac myocytes can control FA mitochondrial entry, but display weak ability to control FA uptake, thus the fate of non beta-oxidized FA appear as a new impairment for the cell. Both the trigger and the regulation of cardiac contraction result from membrane activity, and the other major FA function in the myocardium is their role in membrane homeostasis, through the phospholipid synthesis and remodeling pathways. Sudden death, hypercatecholaminemia, diabetes and heart failure have been associated with an altered PUFA content in cardiac membranes. Experimental data suggest that the 2 metabolic pathways involved in membrane homeostasis may represent therapeutic targets for cytoprotection. The drugs that increase cardiac phospholipid turnover (trimétazidine, ranolazine,...) display anti-ischemic non hemodynamic effect. This effect is based on a redirection of FA utilization towards phospholipid synthesis, which decrease their availability for energy production. A nutritional approach gave also promising results. Besides its anti-arrhythmic effect, the dietary docosahexaenoic acid is able to reduce FA energy consumption and hence oxygen demand. The cardiac metabolic pathways involving FA should be considered as a whole, precariously balanced. The diabetic heart being characterised by

Therapeutic Approaches Using Riboflavin in Mitochondrial Energy Metabolism Disorders.

Science.gov (United States)

Henriques, Bárbara J; Lucas, Tânia G; Gomes, Cláudio M

2016-01-01

Riboflavin, or vitamin B2, plays an important role in the cell as biological precursor of FAD and FMN, two important flavin cofactors which are essential for the structure and function of flavoproteins. Riboflavin has been used in therapeutic approaches of various inborn errors of metabolism, notably in metabolic disorders resulting either from defects in proteins involved in riboflavin metabolism and transport or from defects in flavoenzymes. The scope of this review is to provide an updated perspective of clinical cases in which riboflavin was used as a potential therapeutic agent in disorders affecting mitochondrial energy metabolism. In particular, we discuss available mechanistic insights on the role of riboflavin as a pharmacological chaperone for the recovery of misfolded metabolic flavoenzymes.

Studies on growth, nitrogen and energy metabolism in rats

DEFF Research Database (Denmark)

Thorbek, G; Chwalibog, André; Eggum, B O

1982-01-01

Feed intake, growth, nitrogen retention and energy metabolism were measured in 12 male Wistar rats fed ad lib. for 14 weeks with non-purified diets. The feed intake increased rapidly in 4 weeks time from 16 g/d to 25 g/d, and then it was constant in the following 10 weeks. In relation to metabolic...

Sex differences of human cortical blood flow and energy metabolism.

Science.gov (United States)

Aanerud, Joel; Borghammer, Per; Rodell, Anders; Jónsdottir, Kristjana Y; Gjedde, Albert

2017-07-01

Brain energy metabolism is held to reflect energy demanding processes in neuropil related to the density and activity of synapses. There is recent evidence that men have higher density of synapses in temporal cortex than women. One consequence of these differences would be different rates of cortical energy turnover and blood flow in men and women. To test the hypotheses that rates of oxygen consumption (CMRO 2 ) and cerebral blood flow are higher in men than in women in regions of cerebral cortex, and that the differences persist with aging, we used positron emission tomography to determine cerebral blood flow and cerebral metabolic rate of oxygen as functions of age in healthy volunteers of both sexes. Cerebral metabolic rate of oxygen did not change with age for either sex and there were no differences of mean values of cerebral metabolic rate of oxygen between men and women in cerebral cortex. Women had significant decreases of cerebral blood flow as function of age in frontal and parietal lobes. Young women had significantly higher cerebral blood flow than men in frontal and temporal lobes, but these differences had disappeared at age 65. The absent sex difference of cerebral energy turnover suggests that the known differences of synaptic density between the sexes are counteracted by opposite differences of individual synaptic activity.

A method for allocating renewable energy source subsidies among final energy consumers

International Nuclear Information System (INIS)

Batlle, Carlos

2011-01-01

In a new context of growing need for renewable energy sources (RES), tariff design has become a critical component of energy system regulation. A methodology for allocating the cost of RES subsidies that ensures an optimal balance between compliance with the main regulatory principles of tariff design and each state's specific policy is of cardinal importance in the current context. This paper presents and discusses a novel methodology to allocate the RES subsidy costs, which consists of distributing them among final energy consumers, in proportion to their consumption, regardless of the type of final energy consumed (liquid fuels, gas, electricity or coal). First, the different designs of RES subsidies are categorized and a review of a good number of the RES burden sharing mechanisms implemented in the EU is presented. Then, the proposed methodology is developed on the basis of the basic regulatory principles underlying the tariff design and the current regulatory context in force in the EU. Finally, to illustrate its actual impact in a real case example, the proposed methodology is applied to the Spanish system, in which the burden of extra costs incurred for RES amounts to a very large proportion of the overall energy system costs. - Research highlights: → This paper develops a novel methodology to allocate RES subsidy costs among final energy consumers. → The methodology is built upon the basic tariff design principles and the 3rd package regulations. → It consists of distributing them in proportion to liquid fuels, gas, electricity or coal consumption. → The 20% RES target affects all energy sectors and justifies allocating the extra costs accordingly. → The methodology is applied to the Spanish energy system, where the RES burden is a very significant.

Cellular energy metabolism maintains young status in old queen honey bees (Apis mellifera).

Science.gov (United States)

Lu, Cheng-Yen; Qiu, Jiantai Timothy; Hsu, Chin-Yuan

2018-05-02

Trophocytes and oenocytes of queen honey bees are used in studies of cellular longevity, but their cellular energy metabolism with age is poorly understood. In this study, the molecules involved in cellular energy metabolism were evaluated in the trophocytes and oenocytes of young and old queen bees. The findings indicated that there were no significant differences between young and old queen bees in β-oxidation, glycolysis, and protein synthesis. These results indicate that the cellular energy metabolism of trophocytes and oenocytes in old queen bees is similar to young queen bees and suggests that maintaining cellular energy metabolism in a young status may be associated with the longevity of queen bees. Fat and glycogen accumulation increased with age indicating that old queen bees are older than young queen bees. © 2018 Wiley Periodicals, Inc.

Energy Impact Illinois - Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Olson, Daniel [Senior Energy Efficiency Planner; Plagman, Emily [Senior Energy Planner; Silberhorn, Joey-Lin [Energy Efficiency Program Assistant

2014-02-18

Energy Impact Illinois (EI2) is an alliance of government organizations, nonprofits, and regional utility companies led by the Chicago Metropolitan Agency for Planning (CMAP) that is dedicated to helping communities in the Chicago metropolitan area become more energy efficient. Originally organized as the Chicago Region Retrofit Ramp-Up (CR3), EI2 became part of the nationwide Better Buildings Neighborhood Program (BBNP) in May 2010 after receiving a $25 million award from the U.S. Department of Energy (DOE) authorized through the American Recovery and Reinvestment Act of 2009 (ARRA). The program’s primary goal was to fund initiatives that mitigate barriers to energy efficiency retrofitting activities across residential, multifamily, and commercial building sectors in the seven-county CMAP region and to help to build a sustainable energy efficiency marketplace. The EI2 Final Technical Report provides a detailed review of the strategies, implementation methods, challenges, lessons learned, and final results of the EI2 program during the initial grant period from 2010-2013. During the program period, EI2 successfully increased direct retrofit activity in the region and was able to make a broader impact on the energy efficiency market in the Chicago region. As the period of performance for the initial grant comes to an end, EI2’s legacy raises the bar for the region in terms of helping homeowners and building owners to take action on the continually complex issue of energy efficiency.

Forecast of the energy final consumption for Minas Gerais State

International Nuclear Information System (INIS)

Almeida, P.E.F. de; Bechtlufft, P.C.T.; Araujo, M.E.A.; Vasconcelos, E.C.; Las Casas, H.B. de; Monteiro, M.A.G.

1990-01-01

This paper is included among the activities of the Energy Planning of Minas Gerais State and presents a forecast of the energy final consumption for the State up to year 2010. Two Scenarios are presented involving brazilian economy's evolution, the State's demography and its sectors: residential, services, transportation, agriculture and cattle-breeding and industry. Finally, it shows two forecast on energy final consumption for Minas Gerais State. (author)

Circulating follistatin in relation to energy metabolism

DEFF Research Database (Denmark)

Hansen, Jakob Schiøler; Plomgaard, Peter

2016-01-01

a relation to energy metabolism. In this narrative review, we attempt to reconcile the existing findings on circulating follistatin with the novel concept that circulating follistatin is a liver-derived molecule regulated by the glucagon-to-insulin ratio. The picture emerging is that conditions associated...

Bedside Evaluation of Cerebral Energy Metabolism in Severe Community-Acquired Bacterial Meningitis

DEFF Research Database (Denmark)

Rom Poulsen, Frantz; Schulz, Mette; Jacobsen, Anne

2015-01-01

BACKGROUND: Mortality and morbidity have remained high in bacterial meningitis. Impairment of cerebral energy metabolism probably contributes to unfavorable outcome. Intracerebral microdialysis is routinely used to monitor cerebral energy metabolism, and recent experimental studies indicate...... that this technique may separate ischemia and non-ischemic mitochondrial dysfunction. The present study is a retrospective interpretation of biochemical data obtained in a series of patients with severe community-acquired meningitis. METHODS: Cerebral energy metabolism was monitored in 15 patients with severe...... community-acquired meningitis utilizing intracerebral microdialysis and bedside biochemical analysis. According to previous studies, cerebral ischemia was defined as lactate/pyruvate (LP) ratio >30 with intracerebral pyruvate level

Metabolic sensing neurons and the control of energy homeostasis.

Science.gov (United States)

Levin, Barry E

2006-11-30

The brain and periphery carry on a constant conversation; the periphery informs the brain about its metabolic needs and the brain provides for these needs through its control of somatomotor, autonomic and neurohumoral pathways involved in energy intake, expenditure and storage. Metabolic sensing neurons are the integrators of a variety of metabolic, humoral and neural inputs from the periphery. Such neurons, originally called "glucosensing", also respond to fatty acids, hormones and metabolites from the periphery. They are integrated within neural pathways involved in the regulation of energy homeostasis. Unlike most neurons, they utilize glucose and other metabolites as signaling molecules to regulate their membrane potential and firing rate. For glucosensing neurons, glucokinase acts as the rate-limiting step in glucosensing while the pathways that mediate responses to metabolites like lactate, ketone bodies and fatty acids are less well characterized. Many metabolic sensing neurons also respond to insulin and leptin and other peripheral hormones and receive neural inputs from peripheral organs. Each set of afferent signals arrives with different temporal profiles and by different routes and these inputs are summated at the level of the membrane potential to produce a given neural firing pattern. In some obese individuals, the relative sensitivity of metabolic sensing neurons to various peripheral inputs is genetically reduced. This may provide one mechanism underlying their propensity to become obese when exposed to diets high in fat and caloric density. Thus, metabolic sensing neurons may provide a potential therapeutic target for the treatment of obesity.

Therapeutic Implications of Targeting Energy Metabolism in Breast Cancer

Directory of Open Access Journals (Sweden)

Meena K. Sakharkar

2013-01-01

Full Text Available PPARs are ligand activated transcription factors. PPARγ agonists have been reported as a new and potentially efficacious treatment of inflammation, diabetes, obesity, cancer, AD, and schizophrenia. Since cancer cells show dysregulation of glycolysis they are potentially manageable through changes in metabolic environment. Interestingly, several of the genes involved in maintaining the metabolic environment and the central energy generation pathway are regulated or predicted to be regulated by PPARγ. The use of synthetic PPARγ ligands as drugs and their recent withdrawal/restricted usage highlight the lack of understanding of the molecular basis of these drugs, their off-target effects, and their network. These data further underscores the complexity of nuclear receptor signalling mechanisms. This paper will discuss the function and role of PPARγ in energy metabolism and cancer biology in general and its emergence as a promising therapeutic target in breast cancer.

STAT3 Activities and Energy Metabolism: Dangerous Liaisons

Energy Technology Data Exchange (ETDEWEB)

Camporeale, Annalisa, E-mail: annalisa.camporeale@unito.it [Molecular Biotechnology Center and Department of Molecular Biotechnology and Life Sciences, University of Turin, Via Nizza 52, Turin 10126 (Italy); Demaria, Marco [Buck Institute for Research on Aging, 8001 Redwood Blvd, Novato, CA 94945 (United States); Monteleone, Emanuele [Molecular Biotechnology Center and Department of Molecular Biotechnology and Life Sciences, University of Turin, Via Nizza 52, Turin 10126 (Italy); Giorgi, Carlotta [Department of Experimental and Diagnostic Medicine, Section of General Pathology, Laboratory for Technologies of Advances Therapies (LTTA), University of Ferrara, Via Fossato di Mortara 70, Ferrara 44121 (Italy); Wieckowski, Mariusz R. [Nencki Institute of Experimental Biology, Department of Biochemistry, Pasteur Str. 3, Warsaw 02-093 (Poland); Pinton, Paolo [Department of Experimental and Diagnostic Medicine, Section of General Pathology, Laboratory for Technologies of Advances Therapies (LTTA), University of Ferrara, Via Fossato di Mortara 70, Ferrara 44121 (Italy); Poli, Valeria, E-mail: annalisa.camporeale@unito.it [Molecular Biotechnology Center and Department of Molecular Biotechnology and Life Sciences, University of Turin, Via Nizza 52, Turin 10126 (Italy)

2014-07-31

STAT3 mediates cytokine and growth factor receptor signalling, becoming transcriptionally active upon tyrosine 705 phosphorylation (Y-P). Constitutively Y-P STAT3 is observed in many tumors that become addicted to its activity, and STAT3 transcriptional activation is required for tumor transformation downstream of several oncogenes. We have recently demonstrated that constitutively active STAT3 drives a metabolic switch towards aerobic glycolysis through the transcriptional induction of Hif-1α and the down-regulation of mitochondrial activity, in both MEF cells expressing constitutively active STAT3 (Stat3{sup C/C}) and STAT3-addicted tumor cells. This novel metabolic function is likely involved in mediating pre-oncogenic features in the primary Stat3{sup C/C} MEFs such as resistance to apoptosis and senescence and rapid proliferation. Moreover, it strongly contributes to the ability of primary Stat3{sup C/C} MEFs to undergo malignant transformation upon spontaneous immortalization, a feature that may explain the well known causative link between STAT3 constitutive activity and tumor transformation under chronic inflammatory conditions. Taken together with the recently uncovered role of STAT3 in regulating energy metabolism from within the mitochondrion when phosphorylated on Ser 727, these data place STAT3 at the center of a hub regulating energy metabolism under different conditions, in most cases promoting cell survival, proliferation and malignant transformation even though with distinct mechanisms.

STAT3 Activities and Energy Metabolism: Dangerous Liaisons

International Nuclear Information System (INIS)

Camporeale, Annalisa; Demaria, Marco; Monteleone, Emanuele; Giorgi, Carlotta; Wieckowski, Mariusz R.; Pinton, Paolo; Poli, Valeria

2014-01-01

STAT3 mediates cytokine and growth factor receptor signalling, becoming transcriptionally active upon tyrosine 705 phosphorylation (Y-P). Constitutively Y-P STAT3 is observed in many tumors that become addicted to its activity, and STAT3 transcriptional activation is required for tumor transformation downstream of several oncogenes. We have recently demonstrated that constitutively active STAT3 drives a metabolic switch towards aerobic glycolysis through the transcriptional induction of Hif-1α and the down-regulation of mitochondrial activity, in both MEF cells expressing constitutively active STAT3 (Stat3 C/C ) and STAT3-addicted tumor cells. This novel metabolic function is likely involved in mediating pre-oncogenic features in the primary Stat3 C/C MEFs such as resistance to apoptosis and senescence and rapid proliferation. Moreover, it strongly contributes to the ability of primary Stat3 C/C MEFs to undergo malignant transformation upon spontaneous immortalization, a feature that may explain the well known causative link between STAT3 constitutive activity and tumor transformation under chronic inflammatory conditions. Taken together with the recently uncovered role of STAT3 in regulating energy metabolism from within the mitochondrion when phosphorylated on Ser 727, these data place STAT3 at the center of a hub regulating energy metabolism under different conditions, in most cases promoting cell survival, proliferation and malignant transformation even though with distinct mechanisms

Mitochondrial uncoupling proteins and energy metabolism

Directory of Open Access Journals (Sweden)

Rosa Anna Busiello

2015-02-01

Full Text Available Understanding the metabolic factors that contribute to energy metabolism (EM is critical for the development of new treatments for obesity and related diseases. Mitochondrial oxidative phosphorylation is not perfectly coupled to ATP synthesis, and the process of proton-leak plays a crucial role. Proton-leak accounts for a significant part of the resting metabolic rate and therefore enhancement of this process represents a potential target for obesity treatment. Since their discovery, uncoupling proteins have stimulated great interest due to their involvement in mitochondrial-inducible proton-leak. Despite the widely accepted uncoupling/thermogenic effect of uncoupling protein one (UCP1, which was the first in this family to be discovered, the reactions catalyzed by its homologue UCP3 and the physiological role remain under debate.This review provides an overview of the role played by UCP1 and UCP3 in mitochondrial uncoupling/functionality as well as EM and suggests that they are a potential therapeutic target for treating obesity and its related diseases such as type II diabetes mellitus.

Effects of photoperiod on energy metabolism and thermogenesis in ...

African Journals Online (AJOL)

The plasticity in energy intake, basal metabolic rate (BMR) and nonshivering thermogenesis (NST) was very important for the regulations in energy balance and thermogenesis in Melano-bellied oriental vole exposed to different photoperiod. Change in brown adipose tissue (BAT) cytochrome c oxidase (COX) activity and ...

Performance and Energy Metabolism by Broiler Chickens Fed Maize ...

African Journals Online (AJOL)

Studies were conducted to evaluate the effect of replacing maize grain with different dietary levels of maize and millet offals on performance and energy metabolism in broiler chickens. Proximate composition and metabolizable energy (ME) values were determined. Feeding trial was also conducted to comparemaize and ...

Basal Metabolic Rate and Energy Expenditure of Rural Farmers in ...

African Journals Online (AJOL)

Measurement of basal metabolic rate (BMR) provides an important baseline for the determination of an individual's total energy requirement. The study sought to establish human energy expenditure of rural farmers in Magubike village in Tanzania, through determination of BMR, physical activity level (PAL) and total energy ...

Energy metabolism in mobile, wild-sampled sharks inferred by plasma lipids.

Science.gov (United States)

Gallagher, Austin J; Skubel, Rachel A; Pethybridge, Heidi R; Hammerschlag, Neil

2017-01-01

Evaluating how predators metabolize energy is increasingly useful for conservation physiology, as it can provide information on their current nutritional condition. However, obtaining metabolic information from mobile marine predators is inherently challenging owing to their relative rarity, cryptic nature and often wide-ranging underwater movements. Here, we investigate aspects of energy metabolism in four free-ranging shark species ( n  = 281; blacktip, bull, nurse, and tiger) by measuring three metabolic parameters [plasma triglycerides (TAG), free fatty acids (FFA) and cholesterol (CHOL)] via non-lethal biopsy sampling. Plasma TAG, FFA and total CHOL concentrations (in millimoles per litre) varied inter-specifically and with season, year, and shark length varied within a species. The TAG were highest in the plasma of less active species (nurse and tiger sharks), whereas FFA were highest among species with relatively high energetic demands (blacktip and bull sharks), and CHOL concentrations were highest in bull sharks. Although temporal patterns in all metabolites were varied among species, there appeared to be peaks in the spring and summer, with ratios of TAG/CHOL (a proxy for condition) in all species displaying a notable peak in summer. These results provide baseline information of energy metabolism in large sharks and are an important step in understanding how the metabolic parameters can be assessed through non-lethal sampling in the future. In particular, this study emphasizes the importance of accounting for intra-specific and temporal variability in sampling designs seeking to monitor the nutritional condition and metabolic responses of shark populations.

Mind your step: metabolic energy cost while walking an enforced gait pattern.

Science.gov (United States)

Wezenberg, D; de Haan, A; van Bennekom, C A M; Houdijk, H

2011-04-01

The energy cost of walking could be attributed to energy related to the walking movement and energy related to balance control. In order to differentiate between both components we investigated the energy cost of walking an enforced step pattern, thereby perturbing balance while the walking movement is preserved. Nine healthy subjects walked three times at comfortable walking speed on an instrumented treadmill. The first trial consisted of unconstrained walking. In the next two trials, subject walked while following a step pattern projected on the treadmill. The steps projected were either composed of the averaged step characteristics (periodic trial), or were an exact copy including the variability of the steps taken while walking unconstrained (variable trial). Metabolic energy cost was assessed and center of pressure profiles were analyzed to determine task performance, and to gain insight into the balance control strategies applied. Results showed that the metabolic energy cost was significantly higher in both the periodic and variable trial (8% and 13%, respectively) compared to unconstrained walking. The variation in center of pressure trajectories during single limb support was higher when a gait pattern was enforced, indicating a more active ankle strategy. The increased metabolic energy cost could originate from increased preparatory muscle activation to ensure proper foot placement and a more active ankle strategy to control for lateral balance. These results entail that metabolic energy cost of walking can be influenced significantly by control strategies that do not necessary alter global gait characteristics. Copyright © 2011 Elsevier B.V. All rights reserved.

Metabolic effects of dark chocolate consumption on energy, gut microbiota, and stress-related metabolism in free-living subjects.

Science.gov (United States)

Martin, Francois-Pierre J; Rezzi, Serge; Peré-Trepat, Emma; Kamlage, Beate; Collino, Sebastiano; Leibold, Edgar; Kastler, Jürgen; Rein, Dietrich; Fay, Laurent B; Kochhar, Sunil

2009-12-01

Dietary preferences influence basal human metabolism and gut microbiome activity that in turn may have long-term health consequences. The present study reports the metabolic responses of free living subjects to a daily consumption of 40 g of dark chocolate for up to 14 days. A clinical trial was performed on a population of 30 human subjects, who were classified in low and high anxiety traits using validated psychological questionnaires. Biological fluids (urine and blood plasma) were collected during 3 test days at the beginning, midtime and at the end of a 2 week study. NMR and MS-based metabonomics were employed to study global changes in metabolism due to the chocolate consumption. Human subjects with higher anxiety trait showed a distinct metabolic profile indicative of a different energy homeostasis (lactate, citrate, succinate, trans-aconitate, urea, proline), hormonal metabolism (adrenaline, DOPA, 3-methoxy-tyrosine) and gut microbial activity (methylamines, p-cresol sulfate, hippurate). Dark chocolate reduced the urinary excretion of the stress hormone cortisol and catecholamines and partially normalized stress-related differences in energy metabolism (glycine, citrate, trans-aconitate, proline, beta-alanine) and gut microbial activities (hippurate and p-cresol sulfate). The study provides strong evidence that a daily consumption of 40 g of dark chocolate during a period of 2 weeks is sufficient to modify the metabolism of free living and healthy human subjects, as per variation of both host and gut microbial metabolism.

Energy metabolism in Desulfovibrio vulgaris Hildenborough: insights from transcriptome analysis

Energy Technology Data Exchange (ETDEWEB)

Pereira, Patricia M.; He, Qiang; Valente, Filipa M.A.; Xavier, Antonio V.; Zhou, Jizhong; Pereira, Ines A.C.; Louro, Ricardo O.

2007-11-01

Sulphate-reducing bacteria are important players in the global sulphur and carbon cycles, with considerable economical and ecological impact. However, the process of sulphate respiration is still incompletely understood. Several mechanisms of energy conservation have been proposed, but it is unclear how the different strategies contribute to the overall process. In order to obtain a deeper insight into the energy metabolism of sulphate-reducers whole-genome microarrays were used to compare the transcriptional response of Desulfovibrio vulgaris Hildenborough grown with hydrogen/sulphate, pyruvate/sulphate, pyruvate with limiting sulphate, and lactate/thiosulphate, relative to growth in lactate/sulphate. Growth with hydrogen/sulphate showed the largest number of differentially expressed genes and the largest changes in transcript levels. In this condition the most up-regulated energy metabolism genes were those coding for the periplasmic [NiFeSe]hydrogenase, followed by the Ech hydrogenase. The results also provide evidence for the involvement of formate cycling and the recently proposed ethanol pathway during growth in hydrogen. The pathway involving CO cycling is relevant during growth on lactate and pyruvate, but not during growth in hydrogen as the most down-regulated genes were those coding for the CO-induced hydrogenase. Growth on lactate/thiosulphate reveals a down-regulation of several energymetabolism genes similar to what was observed in the presence of nitrite. This study identifies the role of several proteins involved in the energy metabolism of D. vulgaris and highlights several novel genes related to this process, revealing a more complex bioenergetic metabolism than previously considered.

Thermodynamic Aspects and Reprogramming Cellular Energy Metabolism during the Fibrosis Process

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Alexandre Vallée

2017-11-01

Full Text Available Fibrosis is characterized by fibroblast proliferation and fibroblast differentiation into myofibroblasts, which generate a relaxation-free contraction mechanism associated with excessive collagen synthesis in the extracellular matrix, which promotes irreversible tissue retraction evolving towards fibrosis. From a thermodynamic point of view, the mechanisms leading to fibrosis are irreversible processes that can occur through changing the entropy production rate. The thermodynamic behaviors of metabolic enzymes involved in fibrosis are modified by the dysregulation of both transforming growth factor β (TGF-β signaling and the canonical WNT/β-catenin pathway, leading to aerobic glycolysis, called the Warburg effect. Molecular signaling pathways leading to fibrosis are considered dissipative structures that exchange energy or matter with their environment far from the thermodynamic equilibrium. The myofibroblastic cells arise from exergonic processes by switching the core metabolism from oxidative phosphorylation to glycolysis, which generates energy and reprograms cellular energy metabolism to induce the process of myofibroblast differentiation. Circadian rhythms are far-from-equilibrium thermodynamic processes. They directly participate in regulating the TGF-β and WNT/β-catenin pathways involved in energetic dysregulation and enabling fibrosis. The present review focusses on the thermodynamic implications of the reprogramming of cellular energy metabolism, leading to fibroblast differentiation into myofibroblasts through the positive interplay between TGF-β and WNT/β-catenin pathways underlying in fibrosis.

Comprehensive metabolic characterization of serum osteocalcin action in a large non-diabetic sample

DEFF Research Database (Denmark)

Entenmann, Lukas; Pietzner, Maik; Artati, Anna

2017-01-01

to kynurenine points towards a pro-inflammatory state with increasing OCN. Inverse relations with intermediates of branch-chained amino acid metabolism suggest a link to energy metabolism. Finally, urinary surrogate markers of smoking highlight its adverse effect on OCN metabolism. In conclusion, the present...

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

Association Between Energy Balance and Metabolic Hormone Suppression During Ultraendurance Exercise.

Science.gov (United States)

Geesmann, Bjoern; Gibbs, Jenna C; Mester, Joachim; Koehler, Karsten

2017-08-01

Ultraendurance athletes often accumulate an energy deficit when engaging in ultraendurance exercise, and on completion of the exercise, they exhibit endocrine changes that are reminiscent of starvation. However, it remains unclear whether these endocrine changes are a result of the exercise per se or secondary to the energy deficit and, more important, whether these changes can be attenuated by increased dietary intake. The goal of the study was to assess the relationship between changes in key metabolic hormones after ultraendurance exercise and measures of energy balance. Metabolic hormones, as well as energy intake and expenditure, were assessed in 14 well-trained male cyclists who completed a 1230-km ultraendurance cycling event. After completion of the event, serum testosterone (-67% ± 18%), insulin-like growth factor-1 (IGF-1) (-45% ± 8%), and leptin (-79% ± 9%) were significantly suppressed (P deficit to a 3593-kcal surplus. The marked suppression of testosterone, IGF-1, and leptin after ultraendurance exercise is comparable to changes occurring during acute starvation. The suppression of IGF-1, but not that of other metabolic hormones, was strongly associated with the magnitude of the energy deficit, indicating that athletes who attained a greater energy deficit exhibited a more pronounced drop in IGF-1. Future studies are needed to determine whether increased dietary intake can attenuate the endocrine response to ultraendurance exercise.

Metabolic flexibility as an adaptation to energy resources and requirements in health and disease.

Science.gov (United States)

Smith, Reuben L; Soeters, Maarten R; Wüst, Rob C I; Houtkooper, Riekelt H

2018-04-24

The ability to efficiently adapt metabolism by substrate sensing, trafficking, storage and utilization, dependent on availability and requirement is known as metabolic flexibility. In this review, we discuss the breadth and depth of metabolic flexibility and its impact on health and disease. Metabolic flexibility is essential to maintain energy homeostasis in times of either caloric excess or caloric restriction, and in times of either low or high energy demand, such as during exercise. The liver, adipose tissue and muscle govern systemic metabolic flexibility and manage nutrient sensing, uptake, transport, storage and expenditure by communication via endocrine cues. At a molecular level, metabolic flexibility relies on the configuration of metabolic pathways which is regulated by key metabolic enzymes and transcription factors, many of which interact closely with the mitochondria. Disrupted metabolic flexibility, or metabolic inflexibility, however, is associated with many pathological conditions including metabolic syndrome, type 2 diabetes mellitus, and cancer. Multiple factors like dietary composition and feeding frequency, exercise training, and use of pharmacological compounds influence metabolic flexibility and will be discussed here. Lastly, we outline important advances in metabolic flexibility research and discuss medical horizons and translational aspects.

Mitofusin 2 as a driver that controls energy metabolism and insulin signaling.

Science.gov (United States)

Zorzano, Antonio; Hernández-Alvarez, María Isabel; Sebastián, David; Muñoz, Juan Pablo

2015-04-20

Mitochondrial dynamics is a complex process that impacts on mitochondrial biology. Recent evidence indicates that proteins participating in mitochondrial dynamics have additional cellular roles. Mitofusin 2 (Mfn2) is a potent modulator of mitochondrial metabolism with an impact on energy metabolism in muscle, liver, and hypothalamic neurons. In addition, Mfn2 is subjected to tight regulation. Hence, factors such as proinflammatory cytokines, lipid availability, or glucocorticoids block its expression, whereas exercise and increased energy expenditure promote its upregulation. Importantly, Mfn2 controls cell metabolism and insulin signaling by limiting reactive oxygen species production and by modulation of endoplasmic reticulum stress. In this connection, it is critical to understand precisely the molecular mechanisms involved in the global actions of Mfn2. Future directions should concentrate into the analysis of those mechanisms, and to fully demonstrate that Mfn2 represents a cellular hub that senses the metabolic and hormonal milieu and drives the control of metabolic homeostasis.

Connecting metabolism and reproduction: roles of central energy sensors and key molecular mediators.

Science.gov (United States)

Roa, Juan; Tena-Sempere, Manuel

2014-11-01

It is well established that pubertal activation of the reproductive axis and maintenance of fertility are critically dependent on the magnitude of body energy reserves and the metabolic state of the organism. Hence, conditions of impaired energy homeostasis often result in deregulation of puberty and reproduction, whereas gonadal dysfunction can be associated with the worsening of the metabolic profile and, eventually, changes in body weight. While much progress has taken place in our knowledge about the neuroendocrine mechanisms linking metabolism and reproduction, our understanding of how such dynamic interplay happens is still incomplete. As paradigmatic example, much has been learned in the last two decades on the reproductive roles of key metabolic hormones (such as leptin, insulin and ghrelin), their brain targets and the major transmitters and neuropeptides involved. Yet, the molecular mechanisms whereby metabolic information is translated and engages into the reproductive circuits remain largely unsolved. In this work, we will summarize recent developments in the characterization of the putative central roles of key cellular energy sensors, such as mTOR, in this phenomenon, and will relate these with other molecular mechanisms likely contributing to the brain coupling of energy balance and fertility. In doing so, we aim to provide an updated view of an area that, despite still underdeveloped, may be critically important to fully understand how reproduction and metabolism are tightly connected in health and disease. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Big data in energy. Final project

International Nuclear Information System (INIS)

Fraysse, Clemence; Plaisance, Brice

2015-01-01

Within the context of development of the use of always more abundant digital data in energy production, distribution and consumption networks, for instance as real time input of Smart Grids, the authors propose a description of the present energy sector, of its recent evolutions, of its actors and of its future challenges. They focus on the case of France, but also make reference to other countries where these evolutions of the energy sector are already further advanced. They discuss the evolutions generated by the emergence of the Bid Data on the whole value chain. They also discuss the various challenges associated with these transformations, notably for energy transition, for a better integration of renewable energies into the national energy grid, but also in terms of emergence of an energy related data services sector, and in terms of upheaval of business models. They finally discuss the various obstacles that the Big Data revolution will have to face and overcome to deeply transform the energy sector, notably the risk of a malevolent use of data, and of a loss of confidence from the consumer

Research in High Energy Physics. Final report

Energy Technology Data Exchange (ETDEWEB)

Conway, John S.

2013-08-09

This final report details the work done from January 2010 until April 2013 in the area of experimental and theoretical high energy particle physics and cosmology at the University of California, Davis.

31P-magnetic resonance spectroscopy: Impaired energy metabolism in latent hyperthyroidism

International Nuclear Information System (INIS)

Theissen, P.; Kaldewey, S.; Moka, D.; Bunke, J.; Voth, E.; Schicha, H.

1993-01-01

31 Phosphorous magnetic resonance spectroscopy allows an in vivo examination of energy metabolism. The present study was designed to evaluate whether in patients with latent hyperthyroidism alterations of muscle energy metabolism could be found similar to those observed in patients with overt hyperthyroidism. In 10 patients with overt hyperthyroidism before therapy and 20 with latent hyperthyroidism (also without therapy) and in 24 healthy volunteers magnetic resonance spectroscopy of the calf muscle was performed within a 1.5-Tesla magnet. Muscle concentrations of phosphocreatine, inorganic phosphate, and ATP were quantified compared to an external standard solution of K 2 HPO 4 . In the patients with overt hyperthyroidism and with latent hyperthyroidism a significant decrease of phosphocreatine was found. Further, the ATP concentration in patients with latent and manifest hyperthyroidism tended towards lower values. There were no significant differences in the decrease of phosphocreatine and ATP between both patient groups. Therefore, this study for the first time shows that alterations of energy metabolism in latent hyperthyroidism can be measured and that they are similar to those observed in overt hyperthyroidism. (orig.) [de

Salinity modulates thermotolerance, energy metabolism and stress response in amphipods Gammarus lacustris

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Kseniya P. Vereshchagina

2016-11-01

Full Text Available Temperature and salinity are important abiotic factors for aquatic invertebrates. We investigated the influence of different salinity regimes on thermotolerance, energy metabolism and cellular stress defense mechanisms in amphipods Gammarus lacustris Sars from two populations. We exposed amphipods to different thermal scenarios and determined their survival as well as activity of major antioxidant enzymes (peroxidase, catalase, glutathione S-transferase and parameters of energy metabolism (content of glucose, glycogen, ATP, ADP, AMP and lactate. Amphipods from a freshwater population were more sensitive to the thermal challenge, showing higher mortality during acute and gradual temperature change compared to their counterparts from a saline lake. A more thermotolerant population from a saline lake had high activity of antioxidant enzymes. The energy limitations of the freshwater population (indicated by low baseline glucose levels, downward shift of the critical temperature of aerobic metabolism and inability to maintain steady-state ATP levels during warming was observed, possibly reflecting a trade-off between the energy demands for osmoregulation under the hypo-osmotic condition of a freshwater environment and protection against temperature stress.

High energy reactions in normal metabolism and ageing of animals

International Nuclear Information System (INIS)

Avdonina, E.N.; Nesmeyanov, N.

1983-01-01

Processes involving reactions on highly excited states are thought to be of great importance for normal metabolism and aging. Excess energy of the organism is transferred to result in the formation of highly excited states of macromolecules. UV, visible light or ionizing radiation created partially by the organism itself can change metabolic process rates. According to the authors, aging is associated with the defects of macromolecules owing to high energy processes. Gerontological changes in biological materials result from the elimination of low molecular weight molecules and from the formation of unsaturated compounds. Crosslinking of the compounds, accumulation of collagen and connective tissues, the energetic overload of the organism are listed as important features of aging. (V.N.)

Cytosolic Calcium Coordinates Mitochondrial Energy Metabolism with Presynaptic Activity

Science.gov (United States)

Chouhan, Amit K.; Ivannikov, Maxim V.; Lu, Zhongmin; Sugimori, Mutsuyuki; Llinas, Rodolfo R.; Macleod, Gregory T.

2012-01-01

Most neurons fire in bursts, imposing episodic energy demands, but how these demands are coordinated with oxidative phosphorylation is still unknown. Here, using fluorescence imaging techniques on presynaptic termini of Drosophila motor neurons (MNs), we show that mitochondrial matrix pH (pHm), inner membrane potential (Δψm), and NAD(P)H levels ([NAD(P)H]m) increase within seconds of nerve stimulation. The elevations of pHm, Δψm, and [NAD(P)H]m indicate an increased capacity for ATP production. Elevations in pHm were blocked by manipulations which blocked mitochondrial Ca2+ uptake, including replacement of extracellular Ca2+ with Sr2+, and application of either tetraphenylphosphonium chloride or KB-R7943, indicating that it is Ca2+ that stimulates presynaptic mitochondrial energy metabolism. To place this phenomenon within the context of endogenous neuronal activity, the firing rates of a number of individually identified MNs were determined during fictive locomotion. Surprisingly, although endogenous firing rates are significantly different, there was little difference in presynaptic cytosolic Ca2+ levels ([Ca2+]c) between MNs when each fires at its endogenous rate. The average [Ca2+]c level (329±11nM) was slightly above the average Ca2+ affinity of the mitochondria (281±13nM). In summary, we show that when MNs fire at endogenous rates [Ca2+]c is driven into a range where mitochondria rapidly acquire Ca2+. As we also show that Ca2+ stimulates presynaptic mitochondrial energy metabolism, we conclude that [Ca2+]c levels play an integral role in coordinating mitochondrial energy metabolism with presynaptic activity in Drosophila MNs. PMID:22279208

In Vitro Effects of Sports and Energy Drinks on Streptococcus mutans Biofilm Formation and Metabolic Activity.

Science.gov (United States)

Vinson, LaQuia A; Goodlett, Amy K; Huang, Ruijie; Eckert, George J; Gregory, Richard L

2017-09-15

Sports and energy drinks are being increasingly consumed and contain large amounts of sugars, which are known to increase Streptococcus mutans biofilm formation and metabolic activity. The purpose of this in vitro study was to investigate the effects of sports and energy drinks on S. mutans biofilm formation and metabolic activity. S. mutans UA159 was cultured with and without a dilution (1:3 ratio) of a variety of sports and energy drinks in bacterial media for 24 hours. The biofilm was washed, fixed, and stained. Biofilm growth was evaluated by reading absorbance of the crystal violet. Biofilm metabolic activity was measured by the biofilm-reducing XTT to a water-soluble orange compound. Gatorade Protein Recovery Shake and Starbucks Doubleshot Espresso Energy were found to significantly increase biofilm (30-fold and 22-fold, respectively) and metabolic activity (2-fold and 3-fold, respectively). However, most of the remaining drinks significantly inhibited biofilm growth and metabolic activity. Several sports and energy drinks, with sugars or sugar substitutes as their main ingredients inhibited S. mutans biofilm formation. Among the drinks evaluated, Gatorade Protein Recovery Chocolate Shake and Starbucks Doubleshot Energy appear to have cariogenic potential since they increased the biofilm formation and metabolic activity of S. mutans.

Within-day energy deficiency and metabolic perturbation in male endurance athletes

DEFF Research Database (Denmark)

Torstveit, Monica K; Fahrenholtz, Ida Lysdahl; Stenqvist, Thomas B

2018-01-01

) or normal RMR (RMRratio> 0.90, n=11). Despite no observed differences in 24-hour EB or EA between the groups, subjects with suppressed RMR spent more time in an energy deficit exceeding 400 kcal (20.9 [18.8 - 21.8] hours vs. 10.8 [2.5 - 16.4], P=0.023), and had larger single-hour energy deficits compared......Endurance athletes are at increased risk of relative energy deficiency associated with metabolic perturbation and impaired health. We aimed to estimate and compare within-day energy balance (WDEB) in male athletes with suppressed and normal resting metabolic rate (RMR) and explore if within...... to subjects with normal RMR (3265 ± 1963 kcal vs. -1340 ± 2439, P=0.023). Larger single-hour energy deficits were associated with higher cortisol levels (r = -0.499, P=0.004) and a lower testosterone:cortisol ratio (r = 0.431, P=0.015), but no associations with T3or fasting blood glucose were observed...

Roles for Orexin/Hypocretin in the Control of Energy Balance and Metabolism.

Science.gov (United States)

Goforth, Paulette B; Myers, Martin G

The neuropeptide hypocretin is also commonly referred to as orexin, since its orexigenic action was recognized early. Orexin/hypocretin (OX) neurons project widely throughout the brain and the physiologic and behavioral functions of OX are much more complex than initially conceived based upon the stimulation of feeding. OX most notably controls functions relevant to attention, alertness, and motivation. OX also plays multiple crucial roles in the control of food intake, metabolism, and overall energy balance in mammals. OX signaling not only promotes food-seeking behavior upon short-term fasting to increase food intake and defend body weight, but, conversely, OX signaling also supports energy expenditure to protect against obesity. Furthermore, OX modulates the autonomic nervous system to control glucose metabolism, including during the response to hypoglycemia. Consistently, a variety of nutritional cues (including the hormones leptin and ghrelin) and metabolites (e.g., glucose, amino acids) control OX neurons. In this chapter, we review the control of OX neurons by nutritional/metabolic cues, along with our current understanding of the mechanisms by which OX and OX neurons contribute to the control of energy balance and metabolism.

Impaired cardiac energy metabolism in embryos lacking adrenergic stimulation

Science.gov (United States)

Baker, Candice N.; Gidus, Sarah A.; Price, George F.; Peoples, Jessica N. R.

2014-01-01

As development proceeds from the embryonic to fetal stages, cardiac energy demands increase substantially, and oxidative phosphorylation of ADP to ATP in mitochondria becomes vital. Relatively little, however, is known about the signaling mechanisms regulating the transition from anaerobic to aerobic metabolism that occurs during the embryonic period. The main objective of this study was to test the hypothesis that adrenergic hormones provide critical stimulation of energy metabolism during embryonic/fetal development. We examined ATP and ADP concentrations in mouse embryos lacking adrenergic hormones due to targeted disruption of the essential dopamine β-hydroxylase (Dbh) gene. Embryonic ATP concentrations decreased dramatically, whereas ADP concentrations rose such that the ATP/ADP ratio in the adrenergic-deficient group was nearly 50-fold less than that found in littermate controls by embryonic day 11.5. We also found that cardiac extracellular acidification and oxygen consumption rates were significantly decreased, and mitochondria were significantly larger and more branched in adrenergic-deficient hearts. Notably, however, the mitochondria were intact with well-formed cristae, and there was no significant difference observed in mitochondrial membrane potential. Maternal administration of the adrenergic receptor agonists isoproterenol or l-phenylephrine significantly ameliorated the decreases in ATP observed in Dbh−/− embryos, suggesting that α- and β-adrenergic receptors were effective modulators of ATP concentrations in mouse embryos in vivo. These data demonstrate that adrenergic hormones stimulate cardiac energy metabolism during a critical period of embryonic development. PMID:25516547

Impaired cardiac energy metabolism in embryos lacking adrenergic stimulation.

Science.gov (United States)

Baker, Candice N; Gidus, Sarah A; Price, George F; Peoples, Jessica N R; Ebert, Steven N

2015-03-01

As development proceeds from the embryonic to fetal stages, cardiac energy demands increase substantially, and oxidative phosphorylation of ADP to ATP in mitochondria becomes vital. Relatively little, however, is known about the signaling mechanisms regulating the transition from anaerobic to aerobic metabolism that occurs during the embryonic period. The main objective of this study was to test the hypothesis that adrenergic hormones provide critical stimulation of energy metabolism during embryonic/fetal development. We examined ATP and ADP concentrations in mouse embryos lacking adrenergic hormones due to targeted disruption of the essential dopamine β-hydroxylase (Dbh) gene. Embryonic ATP concentrations decreased dramatically, whereas ADP concentrations rose such that the ATP/ADP ratio in the adrenergic-deficient group was nearly 50-fold less than that found in littermate controls by embryonic day 11.5. We also found that cardiac extracellular acidification and oxygen consumption rates were significantly decreased, and mitochondria were significantly larger and more branched in adrenergic-deficient hearts. Notably, however, the mitochondria were intact with well-formed cristae, and there was no significant difference observed in mitochondrial membrane potential. Maternal administration of the adrenergic receptor agonists isoproterenol or l-phenylephrine significantly ameliorated the decreases in ATP observed in Dbh-/- embryos, suggesting that α- and β-adrenergic receptors were effective modulators of ATP concentrations in mouse embryos in vivo. These data demonstrate that adrenergic hormones stimulate cardiac energy metabolism during a critical period of embryonic development. Copyright © 2015 the American Physiological Society.

Adenylate Kinase and AMP Signaling Networks: Metabolic Monitoring, Signal Communication and Body Energy Sensing

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Andre Terzic

2009-04-01

Full Text Available Adenylate kinase and downstream AMP signaling is an integrated metabolic monitoring system which reads the cellular energy state in order to tune and report signals to metabolic sensors. A network of adenylate kinase isoforms (AK1-AK7 are distributed throughout intracellular compartments, interstitial space and body fluids to regulate energetic and metabolic signaling circuits, securing efficient cell energy economy, signal communication and stress response. The dynamics of adenylate kinase-catalyzed phosphotransfer regulates multiple intracellular and extracellular energy-dependent and nucleotide signaling processes, including excitation-contraction coupling, hormone secretion, cell and ciliary motility, nuclear transport, energetics of cell cycle, DNA synthesis and repair, and developmental programming. Metabolomic analyses indicate that cellular, interstitial and blood AMP levels are potential metabolic signals associated with vital functions including body energy sensing, sleep, hibernation and food intake. Either low or excess AMP signaling has been linked to human disease such as diabetes, obesity and hypertrophic cardiomyopathy. Recent studies indicate that derangements in adenylate kinase-mediated energetic signaling due to mutations in AK1, AK2 or AK7 isoforms are associated with hemolytic anemia, reticular dysgenesis and ciliary dyskinesia. Moreover, hormonal, food and antidiabetic drug actions are frequently coupled to alterations of cellular AMP levels and associated signaling. Thus, by monitoring energy state and generating and distributing AMP metabolic signals adenylate kinase represents a unique hub within the cellular homeostatic network.

Cerebral energy metabolism and the brain's functional network architecture: an integrative review.

Science.gov (United States)

Lord, Louis-David; Expert, Paul; Huckins, Jeremy F; Turkheimer, Federico E

2013-09-01

Recent functional magnetic resonance imaging (fMRI) studies have emphasized the contributions of synchronized activity in distributed brain networks to cognitive processes in both health and disease. The brain's 'functional connectivity' is typically estimated from correlations in the activity time series of anatomically remote areas, and postulated to reflect information flow between neuronal populations. Although the topological properties of functional brain networks have been studied extensively, considerably less is known regarding the neurophysiological and biochemical factors underlying the temporal coordination of large neuronal ensembles. In this review, we highlight the critical contributions of high-frequency electrical oscillations in the γ-band (30 to 100 Hz) to the emergence of functional brain networks. After describing the neurobiological substrates of γ-band dynamics, we specifically discuss the elevated energy requirements of high-frequency neural oscillations, which represent a mechanistic link between the functional connectivity of brain regions and their respective metabolic demands. Experimental evidence is presented for the high oxygen and glucose consumption, and strong mitochondrial performance required to support rhythmic cortical activity in the γ-band. Finally, the implications of mitochondrial impairments and deficits in glucose metabolism for cognition and behavior are discussed in the context of neuropsychiatric and neurodegenerative syndromes characterized by large-scale changes in the organization of functional brain networks.

Energy Storage and Distributed Energy Generation Project, Final Project Report

Energy Technology Data Exchange (ETDEWEB)

Schwank, Johannes; Mader, Jerry; Chen, Xiaoyin; Mi, Chris; Linic, Suljo; Sastry, Ann Marie; Stefanopoulou, Anna; Thompson, Levi; Varde, Keshav

2008-03-31

This report serves as a Final Report under the “Energy Storage and Distribution Energy Generation Project” carried out by the Transportation Energy Center (TEC) at the University of Michigan (UM). An interdisciplinary research team has been working on fundamental and applied research on: -distributed power generation and microgrids, -power electronics, and -advanced energy storage. The long-term objective of the project was to provide a framework for identifying fundamental research solutions to technology challenges of transmission and distribution, with special emphasis on distributed power generation, energy storage, control methodologies, and power electronics for microgrids, and to develop enabling technologies for novel energy storage and harvesting concepts that can be simulated, tested, and scaled up to provide relief for both underserved and overstressed portions of the Nation’s grid. TEC’s research is closely associated with Sections 5.0 and 6.0 of the DOE "Five-year Program Plan for FY2008 to FY2012 for Electric Transmission and Distribution Programs, August 2006.”

Clean Energy Works Oregon Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Jacob, Andria [City of Portland; Cyr, Shirley [Clean Energy Works

2013-12-31

In April 2010, the City of Portland received a $20 million award from the U.S. Department of Energy, as part of the Energy Efficiency and Conservation Block Grant program. This award was appropriated under the American Recovery and Reinvestment Act (ARRA), passed by President Obama in 2009. DOE’s program became known as the Better Buildings Neighborhood Program (BBNP). The BBNP grant objectives directed the City of Portland Bureau of Planning and Sustainability (BPS) as the primary grantee to expand the BPS-led pilot program, Clean Energy Works Portland, into Clean Energy Works Oregon (CEWO), with the mission to deliver thousands of home energy retrofits, create jobs, save energy and reduce carbon dioxide emissions.The Final Technical Report explores the successes and lessons learned from the first 3 years of program implementation.

Sex Differences in Energy Metabolism Need to Be Considered with Lifestyle Modifications in Humans

Directory of Open Access Journals (Sweden)

Betty N. Wu

2011-01-01

Full Text Available Women have a higher proportion of body fat compared to men. However, women consume fewer kilojoules per kilogram lean mass and burn fat more preferentially during exercise compared with men. During gestation, women store even greater amounts of fat that cannot be solely attributed to increased energy intake. These observations suggest that the relationship between kilojoules consumed and kilojoules utilised is different in men and women. The reason for these sex differences in energy metabolism is not known; however, it may relate to sex steroids, differences in insulin resistance, or metabolic effects of other hormones such as leptin. When considering lifestyle modifications, sex differences in energy metabolism should be considered. Moreover, elucidating the regulatory role of hormones in energy homeostasis is important for understanding the pathogenesis of obesity and perhaps in the future may lead to ways to reduce body fat with less energy restriction.

Energy Metabolism and Human Dosimetry of Tritium

International Nuclear Information System (INIS)

Galeriu, D.; Takeda, H.; Melintescu, A.; Trivedi, A.

2005-01-01

In the frame of current revision of human dosimetry of 14 C and tritium, undertaken by the International Commission of Radiological Protection, we propose a novel approach based on energy metabolism and a simple biokinetic model for the dynamics of dietary intake (organic 14 C, tritiated water and Organically Bound Tritium-OBT). The model predicts increased doses for HTO and OBT comparing to ICRP recommendations, supporting recent findings

Decomposing final energy use for heating in the residential sector in Austria

International Nuclear Information System (INIS)

Holzmann, Angela; Adensam, Heidelinde; Kratena, Kurt; Schmid, Erwin

2013-01-01

In Austria a considerable number of measures have been implemented to reduce final energy use for residential heating since the 1990s. The aim of this analysis is to investigate, why – despite these implemented measures – final energy use for heating has not decreased in the expected way. The impact of eight factors on final energy use for heating is quantified by applying the Logarithmic Mean Divisia Index (LMDI I) method. The dataset covers the sector of private households in Austria for the period from 1993 to 2009. The main findings of the analysis are: (1) while technical improvements reduce final energy use for heating significantly, rising comfort needs nearly outweigh these savings. (2) Consumer behaviour reduces calculated final energy use considerably. (3) The extent of this reduction is declining significantly in the period observed. (4) The growing share of single-family houses has increased energy demand for heating in the observed period, though a reversal of this trend is detected from 2007 onwards. (5) The impact of growing floor space per person is the major effect revealed by the analysis. (6) Weather conditions have a major impact on annual fluctuations of energy consumption. -- Highlights: •We did an Index decomposition analysis of the Austrian residential heating demand. •Eight impact factors on heating demand have been identified. •Rising comfort needs outweigh savings caused by technical improvements. •Consumer behaviour has a major impact on residential final energy use for heating. •Weather changes play a major role when analysing annual changes in energy use

The role of energy & fatty acid metabolism in obesity and insulin resistance

NARCIS (Netherlands)

Heemskerk, Mattijs Maria

2015-01-01

In today’s world, more people die from complications of overweight than from underweight. But not all individuals are equally prone to develop metabolic complications, such as obesity and insulin resistance. This thesis focuses on the differences in the energy and fatty acid metabolism that play a

How Energy Metabolism Supports Cerebral Function: Insights from 13C Magnetic Resonance Studies In vivo

Directory of Open Access Journals (Sweden)

Sarah Sonnay

2017-05-01

Full Text Available Cerebral function is associated with exceptionally high metabolic activity, and requires continuous supply of oxygen and nutrients from the blood stream. Since the mid-twentieth century the idea that brain energy metabolism is coupled to neuronal activity has emerged, and a number of studies supported this hypothesis. Moreover, brain energy metabolism was demonstrated to be compartmentalized in neurons and astrocytes, and astrocytic glycolysis was proposed to serve the energetic demands of glutamatergic activity. Shedding light on the role of astrocytes in brain metabolism, the earlier picture of astrocytes being restricted to a scaffold-associated function in the brain is now out of date. With the development and optimization of non-invasive techniques, such as nuclear magnetic resonance spectroscopy (MRS, several groups have worked on assessing cerebral metabolism in vivo. In this context, 1H MRS has allowed the measurements of energy metabolism-related compounds, whose concentrations can vary under different brain activation states. 1H-[13C] MRS, i.e., indirect detection of signals from 13C-coupled 1H, together with infusion of 13C-enriched glucose has provided insights into the coupling between neurotransmission and glucose oxidation. Although these techniques tackle the coupling between neuronal activity and metabolism, they lack chemical specificity and fail in providing information on neuronal and glial metabolic pathways underlying those processes. Currently, the improvement of detection modalities (i.e., direct detection of 13C isotopomers, the progress in building adequate mathematical models along with the increase in magnetic field strength now available render possible detailed compartmentalized metabolic flux characterization. In particular, direct 13C MRS offers more detailed dataset acquisitions and provides information on metabolic interactions between neurons and astrocytes, and their role in supporting neurotransmission. Here

Interrelationships between mitochondrial fusion, energy metabolism and oxidative stress during development in Caenorhabditis elegans

Energy Technology Data Exchange (ETDEWEB)

Yasuda, Kayo [Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Education and Research Support Center, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Hartman, Philip S. [Biology Department, Texas Christian University, Fort Worth, TX 76129 (United States); Ishii, Takamasa [Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Suda, Hitoshi [School of High-Technology for Human Welfare, Tokai University, Nishino 317, Numazu, Shizuoka 410-0395 (Japan); Akatsuka, Akira [Education and Research Support Center, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Shoyama, Tetsuji [School of High-Technology for Human Welfare, Tokai University, Nishino 317, Numazu, Shizuoka 410-0395 (Japan); Miyazawa, Masaki [Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Ishii, Naoaki, E-mail: nishii@is.icc.u-tokai.ac.jp [Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan)

2011-01-21

Research highlights: {yields} Growth and development of a fzo-1 mutant defective in the fusion process of mitochondria was delayed relative to the wild type of Caenorhabditis elegans. {yields} Oxygen sensitivity during larval development, superoxide production and carbonyl protein accumulation of the fzo-1 mutant were similar to wild type. {yields} fzo-1 animals had significantly lower metabolism than did N2 and mev-1 overproducing superoxide from mitochondrial electron transport complex II. {yields} Mitochondrial fusion can profoundly affect energy metabolism and development. -- Abstract: Mitochondria are known to be dynamic structures with the energetically and enzymatically mediated processes of fusion and fission responsible for maintaining a constant flux. Mitochondria also play a role of reactive oxygen species production as a byproduct of energy metabolism. In the current study, interrelationships between mitochondrial fusion, energy metabolism and oxidative stress on development were explored using a fzo-1 mutant defective in the fusion process and a mev-1 mutant overproducing superoxide from mitochondrial electron transport complex II of Caenorhabditis elegans. While growth and development of both single mutants was slightly delayed relative to the wild type, the fzo-1;mev-1 double mutant experienced considerable delay. Oxygen sensitivity during larval development, superoxide production and carbonyl protein accumulation of the fzo-1 mutant were similar to wild type. fzo-1 animals had significantly lower metabolism than did N2 and mev-1. These data indicate that mitochondrial fusion can profoundly affect energy metabolism and development.

Targeting energy metabolism in brain cancer through calorie restriction and the ketogenic diet

Directory of Open Access Journals (Sweden)

Seyfried B

2009-09-01

Full Text Available Malignant brain tumors are a significant health problem in children and adults and are largely unmanageable. As a metabolic disorder involving the dysregulation of glycolysis and respiration (the Warburg effect, malignant brain cancer can be managed through changes in metabolic environment. In contrast to malignant brain tumors that are mostly dependent on glycolysis for energy, normal neurons and glia readily transition to ketone bodies (β-hydroxybutyrate for energy in vivo when glucose levels are reduced. The transition from glucose to ketone bodies as a major energy source is an evolutionary conserved adaptation to food deprivation that permits the survival of normal cells during extreme shifts in nutritional environment. Only those cells with a flexible genome, honed through millions of years of environmental forcing and variability selection, can transition from one energy state to another. We propose a different approach to brain cancer management that exploits the metabolic flexibility of normal cells at the expense of the genetically defective and less metabolically flexible tumor cells. This approach to brain cancer management is supported from recent studies in orthotopic mouse brain tumor models and in human pediatric astrocytoma treated with calorie restriction and the ketogenic diet. Issues of implementation and use protocols are discussed.

Experimental ocean acidification alters the allocation of metabolic energy.

Science.gov (United States)

Pan, T-C Francis; Applebaum, Scott L; Manahan, Donal T

2015-04-14

Energy is required to maintain physiological homeostasis in response to environmental change. Although responses to environmental stressors frequently are assumed to involve high metabolic costs, the biochemical bases of actual energy demands are rarely quantified. We studied the impact of a near-future scenario of ocean acidification [800 µatm partial pressure of CO2 (pCO2)] during the development and growth of an important model organism in developmental and environmental biology, the sea urchin Strongylocentrotus purpuratus. Size, metabolic rate, biochemical content, and gene expression were not different in larvae growing under control and seawater acidification treatments. Measurements limited to those levels of biological analysis did not reveal the biochemical mechanisms of response to ocean acidification that occurred at the cellular level. In vivo rates of protein synthesis and ion transport increased ∼50% under acidification. Importantly, the in vivo physiological increases in ion transport were not predicted from total enzyme activity or gene expression. Under acidification, the increased rates of protein synthesis and ion transport that were sustained in growing larvae collectively accounted for the majority of available ATP (84%). In contrast, embryos and prefeeding and unfed larvae in control treatments allocated on average only 40% of ATP to these same two processes. Understanding the biochemical strategies for accommodating increases in metabolic energy demand and their biological limitations can serve as a quantitative basis for assessing sublethal effects of global change. Variation in the ability to allocate ATP differentially among essential functions may be a key basis of resilience to ocean acidification and other compounding environmental stressors.

Exposure to atrazine affects the expression of key genes in metabolic pathways integral to energy homeostasis in Xenopus laevis tadpoles

International Nuclear Information System (INIS)

Zaya, Renee M.; Amini, Zakariya; Whitaker, Ashley S.; Ide, Charles F.

2011-01-01

In our laboratory, Xenopus laevis tadpoles exposed throughout development to 200 or 400 μg/L atrazine, concentrations reported to periodically occur in puddles, vernal ponds and runoff soon after application, were smaller and had smaller fat bodies (the tadpole's lipid storage organ) than controls. It was hypothesized that these changes were due to atrazine-related perturbations of energy homeostasis. To investigate this hypothesis, selected metabolic responses to exposure at the transcriptional and biochemical levels in atrazine-exposed tadpoles were measured. DNA microarray technology was used to determine which metabolic pathways were affected after developmental exposure to 400 μg/L atrazine. From these data, genes representative of the affected pathways were selected for assay using quantitative real time polymerase chain reaction (qRT-PCR) to measure changes in expression during a 2-week exposure to 400 μg/L. Finally, ATP levels were measured from tadpoles both early in and at termination of exposure to 200 and 400 μg/L. Microarray analysis revealed significant differential gene expression in metabolic pathways involved with energy homeostasis. Pathways with increased transcription were associated with the conversion of lipids and proteins into energy. Pathways with decreased transcription were associated with carbohydrate metabolism, fat storage, and protein synthesis. Using qRT-PCR, changes in gene expression indicative of an early stress response to atrazine were noted. Exposed tadpoles had significant decreases in acyl-CoA dehydrogenase (AD) and glucocorticoid receptor protein (GR) mRNA after 24 h of exposure, and near-significant (p = 0.07) increases in peroxisome proliferator-activated receptor β (PPAR-β) mRNA by 72 h. Decreases in AD suggested decreases in fatty acid β-oxidation while decreases in GR may have been a receptor desensitization response to a glucocorticoid surge. Involvement of PPAR-β, an energy homeostasis regulatory molecule

Exposure to atrazine affects the expression of key genes in metabolic pathways integral to energy homeostasis in Xenopus laevis tadpoles

Energy Technology Data Exchange (ETDEWEB)

Zaya, Renee M., E-mail: renee.zaya@wmich.edu [Great Lakes Environmental and Molecular Sciences Center, Department of Biological Sciences, 3425 Wood Hall, Western Michigan University, 1903 West Michigan Avenue, Kalamazoo, MI 49008 (United States); Amini, Zakariya, E-mail: zakariya.amini@wmich.edu [Great Lakes Environmental and Molecular Sciences Center, Department of Biological Sciences, 3425 Wood Hall, Western Michigan University, 1903 West Michigan Avenue, Kalamazoo, MI 49008 (United States); Whitaker, Ashley S., E-mail: ashley.s.whitaker@wmich.edu [Great Lakes Environmental and Molecular Sciences Center, Department of Biological Sciences, 3425 Wood Hall, Western Michigan University, 1903 West Michigan Avenue, Kalamazoo, MI 49008 (United States); Ide, Charles F., E-mail: charles.ide@wmich.edu [Great Lakes Environmental and Molecular Sciences Center, Department of Biological Sciences, 3425 Wood Hall, Western Michigan University, 1903 West Michigan Avenue, Kalamazoo, MI 49008 (United States)

2011-08-15

In our laboratory, Xenopus laevis tadpoles exposed throughout development to 200 or 400 {mu}g/L atrazine, concentrations reported to periodically occur in puddles, vernal ponds and runoff soon after application, were smaller and had smaller fat bodies (the tadpole's lipid storage organ) than controls. It was hypothesized that these changes were due to atrazine-related perturbations of energy homeostasis. To investigate this hypothesis, selected metabolic responses to exposure at the transcriptional and biochemical levels in atrazine-exposed tadpoles were measured. DNA microarray technology was used to determine which metabolic pathways were affected after developmental exposure to 400 {mu}g/L atrazine. From these data, genes representative of the affected pathways were selected for assay using quantitative real time polymerase chain reaction (qRT-PCR) to measure changes in expression during a 2-week exposure to 400 {mu}g/L. Finally, ATP levels were measured from tadpoles both early in and at termination of exposure to 200 and 400 {mu}g/L. Microarray analysis revealed significant differential gene expression in metabolic pathways involved with energy homeostasis. Pathways with increased transcription were associated with the conversion of lipids and proteins into energy. Pathways with decreased transcription were associated with carbohydrate metabolism, fat storage, and protein synthesis. Using qRT-PCR, changes in gene expression indicative of an early stress response to atrazine were noted. Exposed tadpoles had significant decreases in acyl-CoA dehydrogenase (AD) and glucocorticoid receptor protein (GR) mRNA after 24 h of exposure, and near-significant (p = 0.07) increases in peroxisome proliferator-activated receptor {beta} (PPAR-{beta}) mRNA by 72 h. Decreases in AD suggested decreases in fatty acid {beta}-oxidation while decreases in GR may have been a receptor desensitization response to a glucocorticoid surge. Involvement of PPAR-{beta}, an energy

Effects of photoperiod on energy metabolism and thermogenesis in ...

African Journals Online (AJOL)

Administrator

2010-12-27

Dec 27, 2010 ... levels, the responses of this species were studied in different photoperiods. Experiment data ... thermogenesis. Key words: Melano-bellied oriental vole, photoperiod, energy metabolism, brown adipose tissue, cytochrome c .... Folin phenol method with bovine serum albumin as standard (Lowry et al., 1951).

The Role of Energy Metabolism in Cutaneous Sulfur Mustard Injury

National Research Council Canada - National Science Library

Martens, M. E

2006-01-01

.... Our research has shown that inhibition of energy metabolism and depletion of energy stores are a significant consequence of HD exposure and that this inhibition is severe enough to be a determining factor in both cell survival and repair of HD-induced damage. In this paper we present an overview of our results and conclusions to date and briefly discuss their implications.

Energy accounting for France in 2016 - Final data

International Nuclear Information System (INIS)

Moreau, Sylvain; Bottin, Anne; Carriere, Celine

2017-12-01

This brief report gives a global synthesis of the energy accounting data for France during the year 2016. The main conclusions of the study are: a 2 pc reduction of the energy independence in 2016 (due to the shutdown of several nuclear power plants); the reduction of energy transformation losses due to the lowering of nuclear power generation; a decrease in the final energy consumption (taking into consideration the climate variations); a global stability of energy consumption in the transportation sector; contrasted evolutions of energy consumption in the residential sector (depending on the energy source); a global price decrease for households; a decrease of energy consumption in the industrial sector; a small increase of the power consumption in French overseas territories

Lymphocytes Mitochondrial Physiology as Biomarker of Energy Metabolism during Fasted and Fed Conditions

Directory of Open Access Journals (Sweden)

Erika Cortez

2012-01-01

Full Text Available Mitochondria are central coordinators of energy metabolism, and changes of their physiology have long been associated with metabolic disorders. Thus, observations of energy dynamics in different cell types are of utmost importance. Therefore, tools with quick and easy handling are needed for consistent evaluations of such interventions. In this paper, our main hypothesis is that during different nutritional situations lymphocytes mitochondrial physiology could be associated with the metabolism of other cell types, such as cardiomyocytes, and consequently be used as metabolic biomarker. Blood lymphocytes and heart muscle fibers were obtained from both fed and 24 h-fasted mice, and mitochondrial analysis was assessed by high-resolution respirometry and western blotting. Carbohydrate-linked oxidation and fatty acid oxidation were significantly higher after fasting. Carnitine palmitoil transferase 1 and uncouple protein 2 contents were increased in the fasted group, while the glucose transporters 1 and 4 and the ratio phosphorylated AMP-activated protein kinase/AMPK did not change between groups. In summary, under a nutritional status modification, mitochondria demonstrated earlier adaptive capacity than other metabolic sensors such as glucose transporters and AMPK, suggesting the accuracy of mitochondria physiology of lymphocytes as biomarker for metabolic changes.

Human longevity is characterised by high thyroid stimulating hormone secretion without altered energy metabolism

DEFF Research Database (Denmark)

Jansen, S W; Akintola, A A; Roelfsema, F

2015-01-01

hormone (TH) in an inverse relationship. Greater longevity has been associated with higher TSH and lower TH levels, but mechanisms underlying TSH/TH differences and longevity remain unknown. The HPT axis plays a pivotal role in growth, development and energy metabolism. We report that offspring...... of nonagenarians with at least one nonagenarian sibling have increased TSH secretion but similar bioactivity of TSH and similar TH levels compared to controls. Healthy offspring and spousal controls had similar resting metabolic rate and core body temperature. We propose that pleiotropic effects of the HPT axis...... may favour longevity without altering energy metabolism....

Comparison of the metabolic energy cost of overground and treadmill walking in older adults.

Science.gov (United States)

Berryman, Nicolas; Gayda, Mathieu; Nigam, Anil; Juneau, Martin; Bherer, Louis; Bosquet, Laurent

2012-05-01

We assessed whether the metabolic energy cost of walking was higher when measured overground or on a treadmill in a population of healthy older adults. We also assessed the association between the two testing modes. Participants (n = 20, 14 men and 6 women aged between 65 and 83 years of age) were randomly divided into two groups. Half of them went through the overground-treadmill sequence while the other half did the opposite order. A familiarization visit was held for each participant prior to the actual testing. For both modes of testing, five walking speeds were experimented (0.67, 0.89, 1.11, 1.33 and 1.67 m s(-1)). Oxygen uptake was monitored for all walking speeds. We found a significant difference between treadmill and track metabolic energy cost of walking, whatever the walking speed. The results show that walking on the treadmill requires more metabolic energy than walking overground for all experimental speeds (P < 0.05). The association between both measures was low to moderate (0.17 < ICC < 0.65), and the standard error of measurement represented 6.9-15.7% of the average value. These data indicate that metabolic energy cost of walking results from a treadmill test does not necessarily apply in daily overground activities. Interventions aiming at reducing the metabolic energy cost of walking should be assessed with the same mode as it was proposed during the intervention. If the treadmill mode is necessary for any purposes, functional overground walking tests should be implemented to obtain a more complete and specific evaluation.

Dietary Energy Source in Dairy Cows in Early Lactation: Metabolites and Metabolic Hormones

NARCIS (Netherlands)

Knegsel, van A.T.M.; Brand, van den H.; Graat, E.A.M.; Dijkstra, J.; Jorritsma, R.; Decuypere, M.P.; Tamminga, S.; Kemp, B.

2007-01-01

Negative energy balance-related metabolic disorders suggest that the balance between available lipogenic and glucogenic nutrients is important. The objectives of this study were to compare the effects of a glucogenic or a lipogenic diet on liver triacylglycerides (TAG), metabolites, and metabolic

Resting and exercise energy metabolism in weight-reduced adults with severe obesity.

Science.gov (United States)

Hames, Kazanna C; Coen, Paul M; King, Wendy C; Anthony, Steven J; Stefanovic-Racic, Maja; Toledo, Frederico G S; Lowery, Jolene B; Helbling, Nicole L; Dubé, John J; DeLany, James P; Jakicic, John M; Goodpaster, Bret H

2016-06-01

To determine effects of physical activity (PA) with diet-induced weight loss on energy metabolism in adults with severe obesity. Adults with severe obesity (n = 11) were studied across 6 months of intervention, then compared with controls with less severe obesity (n = 7) or normal weight (n = 9). Indirect calorimetry measured energy metabolism during exercise and rest. Markers of muscle oxidation were determined by immunohistochemistry. Data were presented as medians. The intervention induced 7% weight loss (P = 0.001) and increased vigorous PA by 24 min/wk (P = 0.02). During exercise, energy expenditure decreased, efficiency increased (P ≤ 0.03), and fatty acid oxidation (FAO) did not change. Succinate dehydrogenase increased (P = 0.001), but fiber type remained the same. Post-intervention subjects' resting metabolism remained similar to controls. Efficiency was lower in post-intervention subjects compared with normal-weight controls exercising at 25 W (P ≤ 0.002) and compared with all controls exercising at 60% VO2peak (P ≤ 0.019). Resting and exercise FAO of post-intervention subjects remained similar to adults with less severe obesity. Succinate dehydrogenase and fiber type were similar across all body weight statuses. While metabolic adaptations to PA during weight loss occur in adults with severe obesity, FAO does not change. Resulting FAO during rest and exercise remains similar to adults with less severe obesity. © 2016 The Obesity Society.

In silico search of energy metabolism inhibitors for alternative leishmaniasis treatments.

Science.gov (United States)

Silva, Lourival A; Vinaud, Marina C; Castro, Ana Maria; Cravo, Pedro Vítor L; Bezerra, José Clecildo B

2015-01-01

Leishmaniasis is a complex disease that affects mammals and is caused by approximately 20 distinct protozoa from the genus Leishmania. Leishmaniasis is an endemic disease that exerts a large socioeconomic impact on poor and developing countries. The current treatment for leishmaniasis is complex, expensive, and poorly efficacious. Thus, there is an urgent need to develop more selective, less expensive new drugs. The energy metabolism pathways of Leishmania include several interesting targets for specific inhibitors. In the present study, we sought to establish which energy metabolism enzymes in Leishmania could be targets for inhibitors that have already been approved for the treatment of other diseases. We were able to identify 94 genes and 93 Leishmania energy metabolism targets. Using each gene's designation as a search criterion in the TriTrypDB database, we located the predicted peptide sequences, which in turn were used to interrogate the DrugBank, Therapeutic Target Database (TTD), and PubChem databases. We identified 44 putative targets of which 11 are predicted to be amenable to inhibition by drugs which have already been approved for use in humans for 11 of these targets. We propose that these drugs should be experimentally tested and potentially used in the treatment of leishmaniasis.

[Specific growth rate and the rate of energy metabolism in the ontogenesis of axolotl, Ambystoma mexicanum (Amphibia: Ambystomatidae)].

Science.gov (United States)

Vladimirova, I G; Kleĭmenov, S Iu; Alekseeva, T A; Radzinskaia, L I

2003-01-01

Concordant changes in the rate of energy metabolism and specific growth rate of axolotls have been revealed. Several periods of ontogeny are distinguished, which differ in the ratio of energy metabolism to body weight and, therefore, are described by different allometric equations. It is suggested that the specific growth rate of an animal determines the type of dependence of energy metabolism on body weight.

Sex differences of human cortical blood flow and energy metabolism

DEFF Research Database (Denmark)

Aanerud, Joel; Borghammer, Per; Rodell, Anders

2017-01-01

cerebral blood flow and cerebral metabolic rate of oxygen as functions of age in healthy volunteers of both sexes. Cerebral metabolic rate of oxygen did not change with age for either sex and there were no differences of mean values of cerebral metabolic rate of oxygen between men and women in cerebral...... cortex. Women had significant decreases of cerebral blood flow as function of age in frontal and parietal lobes. Young women had significantly higher cerebral blood flow than men in frontal and temporal lobes, but these differences had disappeared at age 65. The absent sex difference of cerebral energy...... turnover suggests that the known differences of synaptic density between the sexes are counteracted by opposite differences of individual synaptic activity....

Genotype by energy expenditure interaction with metabolic syndrome traits: the Portuguese healthy family study.

Science.gov (United States)

Santos, Daniel M V; Katzmarzyk, Peter T; Diego, Vincent P; Souza, Michele C; Chaves, Raquel N; Blangero, John; Maia, José A R

2013-01-01

Moderate-to-high levels of physical activity are established as preventive factors in metabolic syndrome development. However, there is variability in the phenotypic expression of metabolic syndrome under distinct physical activity conditions. In the present study we applied a Genotype X Environment interaction method to examine the presence of GxEE interaction in the phenotypic expression of metabolic syndrome. A total of 958 subjects, from 294 families of The Portuguese Healthy Family study, were included in the analysis. Total daily energy expenditure was assessed using a 3 day physical activity diary. Six metabolic syndrome related traits, including waist circumference, systolic blood pressure, glucose, HDL cholesterol, total cholesterol and triglycerides, were measured and adjusted for age and sex. GxEE examination was performed on SOLAR 4.3.1. All metabolic syndrome indicators were significantly heritable. The GxEE interaction model fitted the data better than the polygenic model (pmetabolic syndrome traits expression is significantly influenced by the interaction established between total daily energy expenditure and genotypes. Physical activity may be considered an environmental variable that promotes metabolic differences between individuals that are distinctively active.

Citrate Defines a Regulatory Link Between Energy Metabolism and the Liver Hormone Hepcidin

OpenAIRE

Ladeira Courelas da Silva, Ana Rita

2017-01-01

Iron plays a critical role as an oxygen carrier in hemoglobin as well as a constituent of iron-sulfur clusters. Increasing evidence suggests that mechanisms maintaining iron homeostasis cross-talk to intermediary metabolism. The liver hormone hepcidin is the key regulator of systemic iron metabolism. Hepcidin transcriptional control is linked to the nutrient-sensing mTOR pathway, proliferative signals, gluconeogenic responses during starvation and hormones that modulate energy metabolism. The...

Computational Flux Balance Analysis Predicts that Stimulation of Energy Metabolism in Astrocytes and their Metabolic Interactions with Neurons Depend on Uptake of K+ Rather than Glutamate.

Science.gov (United States)

DiNuzzo, Mauro; Giove, Federico; Maraviglia, Bruno; Mangia, Silvia

2017-01-01

Brain activity involves essential functional and metabolic interactions between neurons and astrocytes. The importance of astrocytic functions to neuronal signaling is supported by many experiments reporting high rates of energy consumption and oxidative metabolism in these glial cells. In the brain, almost all energy is consumed by the Na + /K + ATPase, which hydrolyzes 1 ATP to move 3 Na + outside and 2 K + inside the cells. Astrocytes are commonly thought to be primarily involved in transmitter glutamate cycling, a mechanism that however only accounts for few % of brain energy utilization. In order to examine the participation of astrocytic energy metabolism in brain ion homeostasis, here we attempted to devise a simple stoichiometric relation linking glutamatergic neurotransmission to Na + and K + ionic currents. To this end, we took into account ion pumps and voltage/ligand-gated channels using the stoichiometry derived from available energy budget for neocortical signaling and incorporated this stoichiometric relation into a computational metabolic model of neuron-astrocyte interactions. We aimed at reproducing the experimental observations about rates of metabolic pathways obtained by 13 C-NMR spectroscopy in rodent brain. When simulated data matched experiments as well as biophysical calculations, the stoichiometry for voltage/ligand-gated Na + and K + fluxes generated by neuronal activity was close to a 1:1 relationship, and specifically 63/58 Na + /K + ions per glutamate released. We found that astrocytes are stimulated by the extracellular K + exiting neurons in excess of the 3/2 Na + /K + ratio underlying Na + /K + ATPase-catalyzed reaction. Analysis of correlations between neuronal and astrocytic processes indicated that astrocytic K + uptake, but not astrocytic Na + -coupled glutamate uptake, is instrumental for the establishment of neuron-astrocytic metabolic partnership. Our results emphasize the importance of K + in stimulating the activation of

Geochemical constraints on sources of metabolic energy for chemolithoautotrophy in ultramafic-hosted deep-sea hydrothermal systems.

Science.gov (United States)

McCollom, Thomas M

2007-12-01

Numerical models are employed to investigate sources of chemical energy for autotrophic microbial metabolism that develop during mixing of oxidized seawater with strongly reduced fluids discharged from ultramafic-hosted hydrothermal systems on the seafloor. Hydrothermal fluids in these systems are highly enriched in H(2) and CH(4) as a result of alteration of ultramafic rocks (serpentinization) in the subsurface. Based on the availability of chemical energy sources, inferences are made about the likely metabolic diversity, relative abundance, and spatial distribution of microorganisms within ultramafic-hosted systems. Metabolic reactions involving H(2) and CH(4), particularly hydrogen oxidation, methanotrophy, sulfate reduction, and methanogenesis, represent the predominant sources of chemical energy during fluid mixing. Owing to chemical gradients that develop from fluid mixing, aerobic metabolisms are likely to predominate in low-temperature environments (energy per kilogram of hydrothermal fluid, while anaerobic metabolic reactions can supply about 1 kJ, which is sufficient to support a maximum of approximately 120 mg (dry weight) of primary biomass production by aerobic organisms and approximately 20-30 mg biomass by anaerobes. The results indicate that ultramafic-hosted systems are capable of supplying about twice as much chemical energy as analogous deep-sea hydrothermal systems hosted in basaltic rocks.

Energy Metabolism during Anaerobic Methane Oxidation in ANME Archaea

Science.gov (United States)

McGlynn, Shawn E.

2017-01-01

Anaerobic methane oxidation in archaea is often presented to operate via a pathway of “reverse methanogenesis”. However, if the cumulative reactions of a methanogen are run in reverse there is no apparent way to conserve energy. Recent findings suggest that chemiosmotic coupling enzymes known from their use in methylotrophic and acetoclastic methanogens—in addition to unique terminal reductases—biochemically facilitate energy conservation during complete CH4 oxidation to CO2. The apparent enzyme modularity of these organisms highlights how microbes can arrange their energy metabolisms to accommodate diverse chemical potentials in various ecological niches, even in the extreme case of utilizing “reverse” thermodynamic potentials. PMID:28321009

The Gut Microbiota Modulates Energy Metabolism in the Hibernating Brown Bear Ursus arctos.

Science.gov (United States)

Sommer, Felix; Ståhlman, Marcus; Ilkayeva, Olga; Arnemo, Jon M; Kindberg, Jonas; Josefsson, Johan; Newgard, Christopher B; Fröbert, Ole; Bäckhed, Fredrik

2016-02-23

Hibernation is an adaptation that helps many animals to conserve energy during food shortage in winter. Brown bears double their fat depots during summer and use these stored lipids during hibernation. Although bears seasonally become obese, they remain metabolically healthy. We analyzed the microbiota of free-ranging brown bears during their active phase and hibernation. Compared to the active phase, hibernation microbiota had reduced diversity, reduced levels of Firmicutes and Actinobacteria, and increased levels of Bacteroidetes. Several metabolites involved in lipid metabolism, including triglycerides, cholesterol, and bile acids, were also affected by hibernation. Transplantation of the bear microbiota from summer and winter to germ-free mice transferred some of the seasonal metabolic features and demonstrated that the summer microbiota promoted adiposity without impairing glucose tolerance, suggesting that seasonal variation in the microbiota may contribute to host energy metabolism in the hibernating brown bear. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Intestinal Microbiota Contributes to Energy Balance, Metabolic Inflammation, and Insulin Resistance in Obesity

Directory of Open Access Journals (Sweden)

Joseph F. Cavallari

2017-09-01

Full Text Available Obesity is associated with increased risk of developing metabolic diseases such as type 2 diabetes. The origins of obesity are multi-factorial, but ultimately rooted in increased host energy accumulation or retention. The gut microbiota has been implicated in control of host energy balance and nutrient extraction from dietary sources. The microbiota also impacts host immune status and dysbiosis-related inflammation can augment insulin resistance, independently of obesity. Advances in microbial metagenomic analyses and directly manipulating bacterial-host models of obesity have contributed to our understanding of the relationship between gut bacteria and metabolic disease. Foodborne, or drug-mediated perturbations to the gut microbiota can increase metabolic inflammation, insulin resistance, and dysglycemia. There is now some evidence that specific bacterial species can influence obesity and related metabolic defects such as insulin sensitivity. Components of bacteria are sufficient to impact obesity-related changes in metabolism. In fact, different microbial components derived from the bacterial cell wall can increase or decrease insulin resistance. Improving our understanding of the how components of the microbiota alter host metabolism is positioned to aid in the development of dietary interventions, avoiding triggers of dysbiosis, and generating novel therapeutic strategies to combat increasing rates of obesity and diabetes.

Genetic modulation of energy metabolism in birds through mitochondrial function

NARCIS (Netherlands)

Tieleman, B. Irene; Versteegh, Maaike A.; Fries, Anthony; Helm, Barbara; Dingemanse, Niels J.; Gibbs, H. Lisle; Williams, Joseph B.

2009-01-01

Despite their central importance for the evolution of physiological variation, the genetic mechanisms that determine energy expenditure in animals have largely remained unstudied. We used quantitative genetics to confirm that both mass-specific and whole-organism basal metabolic rate (BMR) were

Final Report: N-Acylethanolamine metabolism and the acquisition of photoautotrophy during seedling establishment

Energy Technology Data Exchange (ETDEWEB)

Chapman, Kent

2018-01-29

Research in our labs, supported since 2005 by Basic Energy Sciences, has led to the discovery of a new lipid mediator pathway that influences phytohormone-mediated regulation of plant growth and development—the so-called N-acylethanolamine (NAE) regulatory pathway. This pathway in plants shares conserved metabolic machinery with the endocannabinoid signaling system of vertebrates that regulates a multitude of physiological and behavioral processes in mammals, suggesting that the metabolism of NAEs is an important regulatory feature of eukaryotic biology. Current evidence in plants points to interactions between NAE metabolism, abscisic acid (ABA) signaling and light signaling to modulate seedling establishment and the acquisition of photoautotrophic growth. The proposed research fits well within the mission of Photosynthetic Systems and Physical Biosciences which seek “to understand the processes by which plants, algae and non-medical microbes capture, convert and/or store energy”. The fundamental regulatory processes that govern seedling establishment directly influence the assembly of photosynthetic energy conversion systems in essentially all higher plants. Our main hypothesis is that seedlings coordinate the metabolic depletion of NAEs during seedling establishment through a complex interaction of hydrolysis (by fatty acid amide hydrolase, FAAH) and oxidation (by lipoxygenases, LOX) and that newly-reported oxylipin metabolites of polyunsaturated NAEs help to coordinate seedling development and acquisition of photoautotrophy in response to appropriate environmental cues. Evidence suggests that ethanolmide oxylipins derived from NAEs can reversibly accumulate in seedlings and adjust/arrest seedling establishment and chloroplast development in conjunction with ABA signaling and light-signaling pathways. Our results provide important new information linking the production of small molecule lipid mediators in seedlings to the coordinated development of

Astrocyte glycogen and brain energy metabolism.

Science.gov (United States)

Brown, Angus M; Ransom, Bruce R

2007-09-01

The brain contains glycogen but at low concentration compared with liver and muscle. In the adult brain, glycogen is found predominantly in astrocytes. Astrocyte glycogen content is modulated by a number of factors including some neurotransmitters and ambient glucose concentration. Compelling evidence indicates that astrocyte glycogen breaks down during hypoglycemia to lactate that is transferred to adjacent neurons or axons where it is used aerobically as fuel. In the case of CNS white matter, this source of energy can extend axon function for 20 min or longer. Likewise, during periods of intense neural activity when energy demand exceeds glucose supply, astrocyte glycogen is degraded to lactate, a portion of which is transferred to axons for fuel. Astrocyte glycogen, therefore, offers some protection against hypoglycemic neural injury and ensures that neurons and axons can maintain their function during very intense periods of activation. These emerging principles about the roles of astrocyte glycogen contradict the long held belief that this metabolic pool has little or no functional significance.

Energy Metabolism in the Liver

OpenAIRE

Rui, Liangyou

2014-01-01

The liver is an essential metabolic organ, and its metabolic activity is tightly controlled by insulin and other metabolic hormones. Glucose is metabolized into pyruvate through glycolysis in the cytoplasm, and pyruvate is completely oxidized to generate ATP through the TCA cycle and oxidative phosphorylation in the mitochondria. In the fed state, glycolytic products are used to synthesize fatty acids through de novo lipogenesis. Long-chain fatty acids are incorporated into triacylglycerol, p...

Utilization of dietary glucose in the metabolic syndrome

Directory of Open Access Journals (Sweden)

Alemany Marià

2011-10-01

Full Text Available Abstract This review is focused on the fate of dietary glucose under conditions of chronically high energy (largely fat intake, evolving into the metabolic syndrome. We are adapted to carbohydrate-rich diets similar to those of our ancestors. Glucose is the main energy staple, but fats are our main energy reserves. Starvation drastically reduces glucose availability, forcing the body to shift to fatty acids as main energy substrate, sparing glucose and amino acids. We are not prepared for excess dietary energy, our main defenses being decreased food intake and increased energy expenditure, largely enhanced metabolic activity and thermogenesis. High lipid availability is a powerful factor decreasing glucose and amino acid oxidation. Present-day diets are often hyperenergetic, high on lipids, with abundant protein and limited amounts of starchy carbohydrates. Dietary lipids favor their metabolic processing, saving glucose, which additionally spares amino acids. The glucose excess elicits hyperinsulinemia, which may derive, in the end, into insulin resistance. The available systems of energy disposal could not cope with the excess of substrates, since they are geared for saving not for spendthrift, which results in an unbearable overload of the storage mechanisms. Adipose tissue is the last energy sink, it has to store the energy that cannot be used otherwise. However, adipose tissue growth also has limits, and the excess of energy induces inflammation, helped by the ineffective intervention of the immune system. However, even under this acute situation, the excess of glucose remains, favoring its final conversion to fat. The sum of inflammatory signals and deranged substrate handling induce most of the metabolic syndrome traits: insulin resistance, obesity, diabetes, liver steatosis, hyperlipidemia and their compounded combined effects. Thus, a maintained excess of energy in the diet may result in difficulties in the disposal of glucose, eliciting

Solar Energy Research and Education Foundation. Final reports by task

Energy Technology Data Exchange (ETDEWEB)

von Reis, K.; Waegel, A.S.; Totten, M.

1997-12-10

This document contains final reports for the following tasks: kiosk for the children`s museum renewable energy exhibit and display, internet promotional and educational material, Aurora renewable energy science and engineering, CD-ROM training materials, presentations and traveling display, radio show `Energy Matters`, and newspaper articles and weekly news column.

Lactate rescues neuronal sodium homeostasis during impaired energy metabolism.

Science.gov (United States)

Karus, Claudia; Ziemens, Daniel; Rose, Christine R

2015-01-01

Recently, we established that recurrent activity evokes network sodium oscillations in neurons and astrocytes in hippocampal tissue slices. Interestingly, metabolic integrity of astrocytes was essential for the neurons' capacity to maintain low sodium and to recover from sodium loads, indicating an intimate metabolic coupling between the 2 cell types. Here, we studied if lactate can support neuronal sodium homeostasis during impaired energy metabolism by analyzing whether glucose removal, pharmacological inhibition of glycolysis and/or addition of lactate affect cellular sodium regulation. Furthermore, we studied the effect of lactate on sodium regulation during recurrent network activity and upon inhibition of the glial Krebs cycle by sodium-fluoroacetate. Our results indicate that lactate is preferentially used by neurons. They demonstrate that lactate supports neuronal sodium homeostasis and rescues the effects of glial poisoning by sodium-fluoroacetate. Altogether, they are in line with the proposed transfer of lactate from astrocytes to neurons, the so-called astrocyte-neuron-lactate shuttle.

Lactate rescues neuronal sodium homeostasis during impaired energy metabolism

Science.gov (United States)

Karus, Claudia; Ziemens, Daniel; Rose, Christine R

2015-01-01

Recently, we established that recurrent activity evokes network sodium oscillations in neurons and astrocytes in hippocampal tissue slices. Interestingly, metabolic integrity of astrocytes was essential for the neurons' capacity to maintain low sodium and to recover from sodium loads, indicating an intimate metabolic coupling between the 2 cell types. Here, we studied if lactate can support neuronal sodium homeostasis during impaired energy metabolism by analyzing whether glucose removal, pharmacological inhibition of glycolysis and/or addition of lactate affect cellular sodium regulation. Furthermore, we studied the effect of lactate on sodium regulation during recurrent network activity and upon inhibition of the glial Krebs cycle by sodium-fluoroacetate. Our results indicate that lactate is preferentially used by neurons. They demonstrate that lactate supports neuronal sodium homeostasis and rescues the effects of glial poisoning by sodium-fluoroacetate. Altogether, they are in line with the proposed transfer of lactate from astrocytes to neurons, the so-called astrocyte-neuron-lactate shuttle. PMID:26039160

Military training elicits marked increases in plasma metabolomic signatures of energy metabolism, lipolysis, fatty acid oxidation, and ketogenesis.

Science.gov (United States)

Karl, J Philip; Margolis, Lee M; Murphy, Nancy E; Carrigan, Christopher T; Castellani, John W; Madslien, Elisabeth H; Teien, Hilde-Kristin; Martini, Svein; Montain, Scott J; Pasiakos, Stefan M

2017-09-01

Military training studies provide unique insight into metabolic responses to extreme physiologic stress induced by multiple stressor environments, and the impacts of nutrition in mediating these responses. Advances in metabolomics have provided new approaches for extending current understanding of factors modulating dynamic metabolic responses in these environments. In this study, whole-body metabolic responses to strenuous military training were explored in relation to energy balance and macronutrient intake by performing nontargeted global metabolite profiling on plasma collected from 25 male soldiers before and after completing a 4-day, 51-km cross-country ski march that produced high total daily energy expenditures (25.4 MJ/day [SD 2.3]) and severe energy deficits (13.6 MJ/day [SD 2.5]). Of 737 identified metabolites, 478 changed during the training. Increases in 88% of the free fatty acids and 91% of the acylcarnitines, and decreases in 88% of the mono- and diacylglycerols detected within lipid metabolism pathways were observed. Smaller increases in 75% of the tricarboxylic acid cycle intermediates, and 50% of the branched-chain amino acid metabolites detected were also observed. Changes in multiple metabolites related to lipid metabolism were correlated with body mass loss and energy balance, but not with energy and macronutrient intakes or energy expenditure. These findings are consistent with an increase in energy metabolism, lipolysis, fatty acid oxidation, ketogenesis, and branched-chain amino acid catabolism during strenuous military training. The magnitude of the energy deficit induced by undereating relative to high energy expenditure, rather than macronutrient intake, appeared to drive these changes, particularly within lipid metabolism pathways. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Exposure to atrazine affects the expression of key genes in metabolic pathways integral to energy homeostasis in Xenopus laevis tadpoles.

Science.gov (United States)

Zaya, Renee M; Amini, Zakariya; Whitaker, Ashley S; Ide, Charles F

2011-08-01

In our laboratory, Xenopus laevis tadpoles exposed throughout development to 200 or 400 μg/L atrazine, concentrations reported to periodically occur in puddles, vernal ponds and runoff soon after application, were smaller and had smaller fat bodies (the tadpole's lipid storage organ) than controls. It was hypothesized that these changes were due to atrazine-related perturbations of energy homeostasis. To investigate this hypothesis, selected metabolic responses to exposure at the transcriptional and biochemical levels in atrazine-exposed tadpoles were measured. DNA microarray technology was used to determine which metabolic pathways were affected after developmental exposure to 400 μg/L atrazine. From these data, genes representative of the affected pathways were selected for assay using quantitative real time polymerase chain reaction (qRT-PCR) to measure changes in expression during a 2-week exposure to 400 μg/L. Finally, ATP levels were measured from tadpoles both early in and at termination of exposure to 200 and 400 μg/L. Microarray analysis revealed significant differential gene expression in metabolic pathways involved with energy homeostasis. Pathways with increased transcription were associated with the conversion of lipids and proteins into energy. Pathways with decreased transcription were associated with carbohydrate metabolism, fat storage, and protein synthesis. Using qRT-PCR, changes in gene expression indicative of an early stress response to atrazine were noted. Exposed tadpoles had significant decreases in acyl-CoA dehydrogenase (AD) and glucocorticoid receptor protein (GR) mRNA after 24 h of exposure, and near-significant (p=0.07) increases in peroxisome proliferator-activated receptor β (PPAR-β) mRNA by 72 h. Decreases in AD suggested decreases in fatty acid β-oxidation while decreases in GR may have been a receptor desensitization response to a glucocorticoid surge. Involvement of PPAR-β, an energy homeostasis regulatory molecule, also

Simulating metabolism with statistical thermodynamics.

Science.gov (United States)

Cannon, William R

2014-01-01

New methods are needed for large scale modeling of metabolism that predict metabolite levels and characterize the thermodynamics of individual reactions and pathways. Current approaches use either kinetic simulations, which are difficult to extend to large networks of reactions because of the need for rate constants, or flux-based methods, which have a large number of feasible solutions because they are unconstrained by the law of mass action. This report presents an alternative modeling approach based on statistical thermodynamics. The principles of this approach are demonstrated using a simple set of coupled reactions, and then the system is characterized with respect to the changes in energy, entropy, free energy, and entropy production. Finally, the physical and biochemical insights that this approach can provide for metabolism are demonstrated by application to the tricarboxylic acid (TCA) cycle of Escherichia coli. The reaction and pathway thermodynamics are evaluated and predictions are made regarding changes in concentration of TCA cycle intermediates due to 10- and 100-fold changes in the ratio of NAD+:NADH concentrations. Finally, the assumptions and caveats regarding the use of statistical thermodynamics to model non-equilibrium reactions are discussed.

Changes in energy metabolism accompanying pitting in blueberries stored at low temperature.

Science.gov (United States)

Zhou, Qian; Zhang, Chunlei; Cheng, Shunchang; Wei, Baodong; Liu, Xiuying; Ji, Shujuan

2014-12-01

Low-temperature storage and transport of blueberries is widely practiced in commercial blueberry production. In this research, the storage life of blueberries was extended at low temperature, but fruit stored for 30 d at 0°C pitted after 2d at room-temperature. Fruit cellular structure and physiological parameters accompanying pitting in blueberries were changed. The objective of this research was to characterise properties of energy metabolism accompanying pitting in blueberries during storage, including adenosine phosphates and mitochondrial enzymes involved in stress responses. Physiological and metabolic disorders, changes in cell ultrastructure, energy content and ATPase enzyme activity were observed in pitting blueberries. Energy shortages and increased activity of phenylalanine ammonia lyase (PAL) and lipoxygenase (LOX) were observed in fruit kept at shelf life. The results suggested that sufficient available energy status and a stable enzymatic system in blueberries collectively contribute to improve chilling tolerance, thereby alleviating pitting and maintaining quality of blueberry fruit in long-term cold storage. Copyright © 2014 Elsevier Ltd. All rights reserved.

Within-Day Energy Deficiency and Metabolic Perturbation in Male Endurance Athletes.

Science.gov (United States)

Torstveit, Monica Klungland; Fahrenholtz, Ida; Stenqvist, Thomas B; Sylta, Øystein; Melin, Anna

2018-06-26

Endurance athletes are at increased risk of relative energy deficiency associated with metabolic perturbation and impaired health. We aimed to estimate and compare within-day energy balance in male athletes with suppressed and normal resting metabolic rate (RMR) and explore whether within-day energy deficiency is associated with endocrine markers of energy deficiency. A total of 31 male cyclists, triathletes, and long-distance runners recruited from regional competitive sports clubs were included. The protocol comprised measurements of RMR by ventilated hood and energy intake and energy expenditure to predict RMR ratio (measured RMR/predicted RMR), energy availability, 24-hr energy balance and within-day energy balance in 1-hr intervals, assessment of body composition by dual-energy X-ray absorptiometry, and blood plasma analysis. Subjects were categorized as having suppressed (RMR ratio   0.90, n = 11) RMR. Despite there being no observed differences in 24-hr energy balance or energy availability between the groups, subjects with suppressed RMR spent more time in an energy deficit exceeding 400 kcal (20.9 [18.8-21.8] hr vs. 10.8 [2.5-16.4], p = .023) and had larger single-hour energy deficits compared with subjects with normal RMR (3,265 ± 1,963 kcal vs. -1,340 ± 2,439, p = .023). Larger single-hour energy deficits were associated with higher cortisol levels (r = -.499, p = .004) and a lower testosterone:cortisol ratio (r = .431, p = .015), but no associations with triiodothyronine or fasting blood glucose were observed. In conclusion, within-day energy deficiency was associated with suppressed RMR and catabolic markers in male endurance athletes.

Hypothalamic energy metabolism is impaired by doxorubicin independently of inflammation in non-tumour-bearing rats.

Science.gov (United States)

Antunes, Barbara M M; Lira, Fabio Santos; Pimentel, Gustavo Duarte; Rosa Neto, José Cesar; Esteves, Andrea Maculano; Oyama, Lila Missae; de Souza, Cláudio Teodoro; Gonçalves, Cinara Ludvig; Streck, Emilio Luiz; Rodrigues, Bruno; dos Santos, Ronaldo Vagner; de Mello, Marco Túlio

2015-08-01

We sought to explore the effects of doxorubicin on inflammatory profiles and energy metabolism in the hypothalamus of rats. To investigate these effects, we formed two groups: a control (C) group and a Doxorubicin (DOXO) group. Sixteen rats were randomly assigned to either the control (C) or DOXO groups. The hypothalamus was collected. The levels of interleukin (IL)-1β, IL-6, IL-10, TNF-α and energy metabolism (malate dehydrogenase, complex I and III activities) were analysed in the hypothalamus. The DOXO group exhibited a decreased body weight (p hypothalamus is a central organ that regulates a great number of functions, such as food intake, temperature and energy expenditure, among others. Doxorubicin can lead to deep anorexia and metabolic chaos; thus, we observed the effect of this chemotherapeutic drug on the inflammation and metabolism in rats after the administration of doxorubicin in order to understand the central effect in the hypothalamus. Drug treatment by doxorubicin is used as a cancer therapy; however the use of this drug may cause harmful alterations to the metabolism. Thus, further investigations are needed on the impact of drug therapy over the long term. Copyright © 2015 John Wiley & Sons, Ltd.

LGR4 and its role in intestinal protection and energy metabolism

Directory of Open Access Journals (Sweden)

Ziru eLi

2015-08-01

Full Text Available Leucine-rich repeat-containing G protein-coupled receptors (LGRs were identified by the unique nature of their long leucine-rich repeat extracellular domains. Distinct from classical G protein-coupled receptors which act via G proteins, LGR4 functions mainly through Wnt/β-catenin signaling to regulate cell proliferation, differentiation, and adult stem cell homeostasis. LGR4 is widely expressed in tissues ranging from the reproductive system, urinary system, sensory organs, digestive system, and the central nervous system, indicating LGR4 may have multiple functions in development. Here we focus on the digestive system by reviewing its effects on crypt cells differentiation and stem cells maintenance, which are important for cell regeneration after injury. Through effects on Wnt/β-catenin signaling and cell proliferation, LGR4 and its endogenous ligands, R-spondins, are involved in colon tumorigenesis. LGR4 also contributes to regulation of energy metabolism, including food intake, energy expenditure and lipid metabolism, as well as pancreatic β-cell proliferation and insulin secretion. This review summarizes the identification of LGR4, its endogenous ligand, ligand-receptor binding and intracellular signaling. Physiological functions include intestinal development and energy metabolism. The potential effects of LGR4 and its ligand in the treatment of inflammatory bowel disease, chemoradiotherapy induced gut damage, colorectal cancer and diabetes are also discussed.

Going beyond energy intensity to understand the energy metabolism of nations: The case of Argentina

International Nuclear Information System (INIS)

Recalde, Marina; Ramos-Martin, Jesús

2012-01-01

The link between energy consumption and economic growth has been widely studied in the economic literature. Understanding this relationship is important from both an environmental and a socio-economic point of view, as energy consumption is crucial to economic activity and human environmental impact. This relevance is even higher for developing countries, since energy consumption per unit of output varies through the phases of development, increasing from an agricultural stage to an industrial one and then decreasing for certain service based economies. In the Argentinean case, the relevance of energy consumption to economic development seems to be particularly important. While energy intensity seems to exhibit a U-Shaped curve from 1990 to 2003 decreasing slightly after that year, total energy consumption increases along the period of analysis. Why does this happen? How can we relate this result with the sustainability debate? All these questions are very important due to Argentinean hydrocarbons dependence and due to the recent reduction in oil and natural gas reserves, which can lead to a lack of security of supply. In this paper we study Argentinean energy consumption pattern for the period 1990–2007, to discuss current and future energy and economic sustainability. To this purpose, we developed a conventional analysis, studying energy intensity, and a non conventional analysis, using the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) accounting methodology. Both methodologies show that the development process followed by Argentina has not been good enough to assure sustainability in the long term. Instead of improving energy use, energy intensity has increased. The current composition of its energy mix, and the recent economic crisis in Argentina, as well as its development path, are some of the possible explanations. -- Highlights: ► We analyze Argentinean energy consumption and social metabolism using MuSIASEM. �

Hypothalamic control of energy metabolism via the autonomic nervous system

NARCIS (Netherlands)

Kalsbeek, A.; Bruinstroop, E.; Yi, C. X.; Klieverik, L. P.; La Fleur, S. E.; Fliers, E.

2010-01-01

The hypothalamic control of hepatic glucose production is an evident aspect of energy homeostasis. In addition to the control of glucose metabolism by the circadian timing system, the hypothalamus also serves as a key relay center for (humoral) feedback information from the periphery, with the

The SCFA receptor GPR43 and energy metabolism

Directory of Open Access Journals (Sweden)

Ikuo eKimura

2014-06-01

Full Text Available Free fatty acids (FFAs are essential nutrients and act as signaling molecules in various cellular processes via binding with FFA receptors. Of these receptors, GPR43 is activated by short chain fatty acids (SCFAs; e.g., acetate, propionate, and butyrate. During feeding, SCFAs are produced by microbial fermentation of dietary fiber in the gut, and these SCFAs become important energy sources for the host. The gut microbiota affects nutrient acquisition and energy regulation of the host and can influence the development of obesity, insulin resistance, and diabetes. Recently, GPR43 has been reported to regulate host energy homeostasis in the gastrointestinal tract and adipose tissues. Hence, GPR43 is also thought to be a potential drug target for metabolic disorders, such as obesity and diabetes. In this review, we summarize the identification, structure, and activities of GPR43, with a focus on host energy regulation, and present an essential overview of our current understanding of its physiological roles in host energy regulation that is mediated by gut microbiota. We also discuss the potential for GPR43 as a therapeutic target.

α/β-Hydrolase Domain 6 in the Ventromedial Hypothalamus Controls Energy Metabolism Flexibility

Directory of Open Access Journals (Sweden)

Alexandre Fisette

2016-10-01

Full Text Available α/β-Hydrolase domain 6 (ABHD6 is a monoacylglycerol hydrolase that degrades the endocannabinoid 2-arachidonoylglycerol (2-AG. Although complete or peripheral ABHD6 loss of function is protective against diet-induced obesity and insulin resistance, the role of ABHD6 in the central control of energy balance is unknown. Using a viral-mediated knockout approach, targeted endocannabinoid measures, and pharmacology, we discovered that mice lacking ABHD6 from neurons of the ventromedial hypothalamus (VMHKO have higher VMH 2-AG levels in conditions of endocannabinoid recruitment and fail to physiologically adapt to key metabolic challenges. VMHKO mice exhibited blunted fasting-induced feeding and reduced food intake, energy expenditure, and adaptive thermogenesis in response to cold exposure, high-fat feeding, and dieting (transition to a low-fat diet. Our findings identify ABHD6 as a regulator of the counter-regulatory responses to major metabolic shifts, including fasting, nutrient excess, cold, and dieting, thereby highlighting the importance of ABHD6 in the VMH in mediating energy metabolism flexibility.

Neutron emission effects on final fragments mass and kinetic energy distribution from low energy fission of 234U

International Nuclear Information System (INIS)

Montoya, M.; Rojas, J.; Lobato, I.

2008-01-01

The standard deviation of the final kinetic energy distribution (σ e ) as a function of mass of final fragments (m) from low energy fission of 234 U, measured with the Lohengrin spectrometer by Belhafaf et al., presents a peak around m = 109 and another around m = 122. The authors attribute the first peak to the evaporation of a large number of neutrons around the corresponding mass number, i.e. there is no peak on the standard deviation of the primary kinetic energy distribution (σ E ) as a function of primary fragment mass (A). The second peak is attributed to a real peak on σ E (A). However, theoretical calculations related to primary distributions made by H.R. Faust and Z. Bao do not suggest any peak on σ E (A). In order to clarify this apparent controversy, we have made a numerical experiment in which the masses and the kinetic energy of final fragments are calculated, assuming an initial distribution of the kinetic energy without structures on the standard deviation as function of fragment mass. As a result we obtain a pronounced peak on σ e (m) curve around m = 109, a depletion from m = 121 to m = 129, and an small peak around m = 122, which is not as great as that measured by Belhafaf et al. Our simulation also reproduces the experimental results on the yield of the final mass Y(m), the average number of emitted neutrons as a function of the provisional mass (calculated from the values of the final kinetic energy of the complementary fragments) and the average value of fragment kinetic energy as a function of the final mass. From our results we conclude that there are no peaks on the σ E (A) curve, and the observed peaks on σ e (m) are due to the emitted neutron multiplicity and the variation of the average fragment kinetic energy as a function of primary fragment mass. (Author)

Unique flexibility in energy metabolism allows mycobacteria to combat starvation and hypoxia.

Directory of Open Access Journals (Sweden)

Michael Berney

Full Text Available Mycobacteria are a group of obligate aerobes that require oxygen for growth, but paradoxically have the ability to survive and metabolize under hypoxia. The mechanisms responsible for this metabolic plasticity are unknown. Here, we report on the adaptation of Mycobacterium smegmatis to slow growth rate and hypoxia using carbon-limited continuous culture. When M. smegmatis is switched from a 4.6 h to a 69 h doubling time at a constant oxygen saturation of 50%, the cells respond through the down regulation of respiratory chain components and the F1Fo-ATP synthase, consistent with the cells lower demand for energy at a reduced growth rate. This was paralleled by an up regulation of molecular machinery that allowed more efficient energy generation (i.e. Complex I and the use of alternative electron donors (e.g. hydrogenases and primary dehydrogenases to maintain the flow of reducing equivalents to the electron transport chain during conditions of severe energy limitation. A hydrogenase mutant showed a 40% reduction in growth yield highlighting the importance of this enzyme in adaptation to low energy supply. Slow growing cells at 50% oxygen saturation subjected to hypoxia (0.6% oxygen saturation responded by switching on oxygen scavenging cytochrome bd, proton-translocating cytochrome bc1-aa3 supercomplex, another putative hydrogenase, and by substituting NAD+-dependent enzymes with ferredoxin-dependent enzymes thus highlighting a new pattern of mycobacterial adaptation to hypoxia. The expression of ferredoxins and a hydrogenase provides a potential conduit for disposing of and transferring electrons in the absence of exogenous electron acceptors. The use of ferredoxin-dependent enzymes would allow the cell to maintain a high carbon flux through its central carbon metabolism independent of the NAD+/NADH ratio. These data demonstrate the remarkable metabolic plasticity of the mycobacterial cell and provide a new framework for understanding their

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

Science.gov (United States)

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.

Energy metabolism and glutamate-glutamine cycle in the brain: a stoichiometric modeling perspective.

Science.gov (United States)

Massucci, Francesco A; DiNuzzo, Mauro; Giove, Federico; Maraviglia, Bruno; Castillo, Isaac Perez; Marinari, Enzo; De Martino, Andrea

2013-10-10

The energetics of cerebral activity critically relies on the functional and metabolic interactions between neurons and astrocytes. Important open questions include the relation between neuronal versus astrocytic energy demand, glucose uptake and intercellular lactate transfer, as well as their dependence on the level of activity. We have developed a large-scale, constraint-based network model of the metabolic partnership between astrocytes and glutamatergic neurons that allows for a quantitative appraisal of the extent to which stoichiometry alone drives the energetics of the system. We find that the velocity of the glutamate-glutamine cycle (Vcyc) explains part of the uncoupling between glucose and oxygen utilization at increasing Vcyc levels. Thus, we are able to characterize different activation states in terms of the tissue oxygen-glucose index (OGI). Calculations show that glucose is taken up and metabolized according to cellular energy requirements, and that partitioning of the sugar between different cell types is not significantly affected by Vcyc. Furthermore, both the direction and magnitude of the lactate shuttle between neurons and astrocytes turn out to depend on the relative cell glucose uptake while being roughly independent of Vcyc. These findings suggest that, in absence of ad hoc activity-related constraints on neuronal and astrocytic metabolism, the glutamate-glutamine cycle does not control the relative energy demand of neurons and astrocytes, and hence their glucose uptake and lactate exchange.

Energy metabolism and glutamate-glutamine cycle in the brain: a stoichiometric modeling perspective

Science.gov (United States)

2013-01-01

Background The energetics of cerebral activity critically relies on the functional and metabolic interactions between neurons and astrocytes. Important open questions include the relation between neuronal versus astrocytic energy demand, glucose uptake and intercellular lactate transfer, as well as their dependence on the level of activity. Results We have developed a large-scale, constraint-based network model of the metabolic partnership between astrocytes and glutamatergic neurons that allows for a quantitative appraisal of the extent to which stoichiometry alone drives the energetics of the system. We find that the velocity of the glutamate-glutamine cycle (Vcyc) explains part of the uncoupling between glucose and oxygen utilization at increasing Vcyc levels. Thus, we are able to characterize different activation states in terms of the tissue oxygen-glucose index (OGI). Calculations show that glucose is taken up and metabolized according to cellular energy requirements, and that partitioning of the sugar between different cell types is not significantly affected by Vcyc. Furthermore, both the direction and magnitude of the lactate shuttle between neurons and astrocytes turn out to depend on the relative cell glucose uptake while being roughly independent of Vcyc. Conclusions These findings suggest that, in absence of ad hoc activity-related constraints on neuronal and astrocytic metabolism, the glutamate-glutamine cycle does not control the relative energy demand of neurons and astrocytes, and hence their glucose uptake and lactate exchange. PMID:24112710

Energy metabolism in BPH/2J genetically hypertensive mice.

Science.gov (United States)

Jackson, Kristy L; Nguyen-Huu, Thu-Phuc; Davern, Pamela J; Head, Geoffrey A

2014-05-01

Recent evidence indicates that genetic hypertension in BPH/2J mice is sympathetically mediated, but these mice also have lower body weight (BW) and elevated locomotor activity compared with BPN/3J normotensive mice, suggestive of metabolic abnormalities. The aim of the present study was to determine whether hypertension in BPH/2J mice is associated with metabolic differences. Whole-body metabolic and cardiovascular parameters were measured over 24 h by indirect calorimetry and radiotelemetry respectively, in conscious young (10-13 weeks) and older (22-23 weeks) BPH/2J, normotensive BPN/3J and C57Bl6 mice. Blood pressure (BP) was greater in BPH/2J compared with both normotensive strains at both ages (PBPH/2J compared with BPN/3J mice (PBPH/2J and normotensive mice when adjusted for activity (P>0.1) suggesting differences in this relationship are not responsible for hypertension. EchoMRI revealed that percentage body composition was comparable in BPN/3J and BPH/2J mice (P>0.1) and both strains gained weight similarly with age (P=0.3). Taken together, the present findings indicate that hypertension in BPH/2J mice does not appear to be related to altered energy metabolism.

Energy metabolism of rat cerebral cortex, hypothalamus and hypophysis during ageing.

Science.gov (United States)

Villa, R F; Ferrari, F; Gorini, A

2012-12-27

Ageing is one of the main risk factors for brain disorders. According to the neuroendocrine theory, ageing modifies the sensitivity of hypothalamus-pituitary-adrenal axis to homoeostatic signals coming from the cerebral cortex. The relationships between the energy metabolism of these areas have not been considered yet, in particular with respect to ageing. For these reasons, this study was undertaken to systematically investigate in female Sprague-Dawley rats aged 4, 6, 12, 18, 24, 28 months and in 4-month-old male ones, the catalytic properties of energy-linked enzymes of the Krebs' cycle, electron transport chain, glutamate and related amino acids on different mitochondrial subpopulations, i.e. non-synaptic perikaryal and intra-synaptic (two types) mitochondria. The biochemical enzymatic pattern of these mitochondria shows different expression of the above-mentioned enzymatic activities in the investigated brain areas, including frontal cerebral cortex, hippocampus, striatum, hypothalamus and hypophysis. The study shows that: (i) the energy metabolism of the frontal cerebral cortex is poorly affected by physiological ageing; (ii) the biochemical machinery of non-synaptic perikaryal mitochondria is differently expressed in the considered brain areas; (iii) at 4-6 months, hypothalamus and hypophysis possess lower oxidative metabolism with respect to the frontal cerebral cortex while (iv), during ageing, the opposite situation occurs. We hypothesised that these metabolic modifications likely try to grant HPA functionality in response to the incoming external stress stimuli increased during ageing. It is particularly notable that age-related changes in brain bioenergetics and in mitochondrial functionality may be considered as remarkable factors during physiological ageing and should play important roles in predisposing the brain to physiopathological events, tightly related to molecular mechanisms evoked for pharmacological treatments. Copyright © 2012 IBRO

Regional cerebral energy metabolism during intravenous anesthesia with etomidate, ketamine or thiopental

International Nuclear Information System (INIS)

Davis, D.W.

1987-01-01

Regional brain glucose utilization (rCMRglc) was measured in rats during steady-state levels of intravenous anesthesia to determine if alterations in brain function due to anesthesia could provide information on the mechanisms of anesthesia. Intravenous anesthetics from three different chemical classes were studied: etomidate, ketamine and thiopental. All rCMRglc experiments were conducted in freely moving rats in isolation chambers, with the use of [6- 14 C] glucose and guantitative autoradiography. Etomidate caused a rostral-to-caudal gradient of depression of rCMRglc. The four doses of etomidate did not differ in their effects on energy metabolism. Sub-anesthetic (5 mg kg -1 ) and anesthetic (30 mg kg -1 ) doses of ketamine produced markedly different patterns of behavior. Brain energy metabolism during the sub-anesthetic dose was stimulated in most regions, while the anesthetic dose selectively stimulated the hippocampus, leaving most brain regions unaffected. Thiopental produced a dose-dependent reduction of rCMRglc in all gray matter regions. No brain region was selectively affected. Comparison of the drug-specific alterations of cerebral energy metabolism suggests these anesthetics do not act through a common mechanism. The hypothesis that each acts by binding to specific cell membrane receptors is consistent with these observations

Changes in Microbial Energy Metabolism Measured by Nanocalorimetry during Growth Phase Transitions

Science.gov (United States)

Robador, Alberto; LaRowe, Douglas E.; Finkel, Steven E.; Amend, Jan P.; Nealson, Kenneth H.

2018-01-01

Calorimetric measurements of the change in heat due to microbial metabolic activity convey information about the kinetics, as well as the thermodynamics, of all chemical reactions taking place in a cell. Calorimetric measurements of heat production made on bacterial cultures have recorded the energy yields of all co-occurring microbial metabolic reactions, but this is a complex, composite signal that is difficult to interpret. Here we show that nanocalorimetry can be used in combination with enumeration of viable cell counts, oxygen consumption rates, cellular protein content, and thermodynamic calculations to assess catabolic rates of an isolate of Shewanella oneidensis MR-1 and infer what fraction of the chemical energy is assimilated by the culture into biomass and what fraction is dissipated in the form of heat under different limiting conditions. In particular, our results demonstrate that catabolic rates are not necessarily coupled to rates of cell division, but rather, to physiological rearrangements of S. oneidensis MR-1 upon growth phase transitions. In addition, we conclude that the heat released by growing microorganisms can be measured in order to understand the physiochemical nature of the energy transformation and dissipation associated with microbial metabolic activity in conditions approaching those found in natural systems. PMID:29449836

Targeting energy metabolism in brain cancer with calorically restricted ketogenic diets.

Science.gov (United States)

Seyfried, Thomas N; Kiebish, Michael; Mukherjee, Purna; Marsh, Jeremy

2008-11-01

Information is presented on the calorically restricted ketogenic diet (CRKD) as an alternative therapy for brain cancer. In contrast to normal neurons and glia, which evolved to metabolize ketone bodies as an alternative fuel to glucose under energy-restricted conditions, brain tumor cells are largely glycolytic due to mitochondrial defects and have a reduced ability to metabolize ketone bodies. The CRKD is effective in managing brain tumor growth in animal models and in patients, and appears to act through antiangiogenic, anti-inflammatory, and proapoptotic mechanisms.

In vivo imaging of cerebral energy metabolism with two-photon fluorescence lifetime microscopy of NADH.

Science.gov (United States)

Yaseen, Mohammad A; Sakadžić, Sava; Wu, Weicheng; Becker, Wolfgang; Kasischke, Karl A; Boas, David A

2013-02-01

Minimally invasive, specific measurement of cellular energy metabolism is crucial for understanding cerebral pathophysiology. Here, we present high-resolution, in vivo observations of autofluorescence lifetime as a biomarker of cerebral energy metabolism in exposed rat cortices. We describe a customized two-photon imaging system with time correlated single photon counting detection and specialized software for modeling multiple-component fits of fluorescence decay and monitoring their transient behaviors. In vivo cerebral NADH fluorescence suggests the presence of four distinct components, which respond differently to brief periods of anoxia and likely indicate different enzymatic formulations. Individual components show potential as indicators of specific molecular pathways involved in oxidative metabolism.

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.

GH and IGF1: roles in energy metabolism of long-living GH mutant mice.

Science.gov (United States)

Brown-Borg, Holly M; Bartke, Andrzej

2012-06-01

Of the multiple theories to explain exceptional longevity, the most robust of these has centered on the reduction of three anabolic protein hormones, growth hormone (GH), insulin-like growth factor, and insulin. GH mutant mice live 50% longer and exhibit significant differences in several aspects of energy metabolism as compared with wild-type mice. Mitochondrial metabolism is upregulated in the absence of GH, whereas in GH transgenic mice and dwarf mice treated with GH, multiple aspects of these pathways are suppressed. Core body temperature is markedly lower in dwarf mice, yet whole-body metabolism, as measured by indirect calorimetry, is surprisingly higher in Ames dwarf and Ghr-/- mice compared with normal controls. Elevated adiponectin, a key antiinflammatory cytokine, is also very likely to contribute to longevity in these mice. Thus, several important components related to energy metabolism are altered in GH mutant mice, and these differences are likely critical in aging processes and life-span extension.

'Key' sectors in final energy consumption: an input-output application to the Spanish case

International Nuclear Information System (INIS)

Alcantara, Vicent; Padilla, Emilio

2003-01-01

In this paper we analyze the determination of 'key' sectors in the final energy consumption. We approach this issue from an input-output perspective and we design a methodology based on the elasticities of the demands of final energy consumption. As an exercise, we apply the proposed methodology to the Spanish economy. The analysis allows us to indicate the greater or lesser relevance of the different sectors in the consumption of final energy, pointing out which sectors deserve greater attention in the Spanish case and showing the implications for energy policy

Guideline for Achieving a Target Share of Renewable Energy in Final Energy Consumption in Slovenia Until 2020

International Nuclear Information System (INIS)

Brecevic, Dj.

2009-01-01

European parliament's and Council for energy usage from renewable sources promotion's directive proposal determines acceptation of National action plan for every member state. General national goal for renewable energy share in final consumption in year 2020, defined in proposal, is 25 % energy from renewable sources in final energy consumption. Paper presents plan for renewable energy sources usage in electricity production and activities, which will be necessary to be held by organizations, which are carriers of energy activities, for building new capacities or rebuilding existing ones for electricity production from renewable energy sources. Purpose of plan is additional 3.000 GWh electricity production in year 2020 in comparison with today's electricity production from renewable energy sources. Accepted goal will be obligatory for organizations as carriers of energy activities for their social responsibility for obligations fulfillment and determined goals achievement. Report represents necessary steps that state has to make to reach bigger interest of investors for renewable energy investments and special attention is stressed on completion of regulation with goal to create suitable platform for future investors.(author).

Environmental physiology: effects of energy-related pollutants on daily cycles of energy metabolism, motor activity, and thermoregulation

International Nuclear Information System (INIS)

Sacher, G.A.; Rosenberg, R.S.; Duffy, P.H.; Obermeyer, W.; Russell, J.J.

1979-01-01

This section contains a summary of research on the effects of energy-related pollutants on daily cycles of energy metabolism, motor activity, and thermoregulation. So far, mice have been exposed to fast neutron-gamma radiation or to the chemical effluents of an atmospheric pressure experimental fluidized-bed combustor. The physiological parameters measured included: O 2 consumption; CO 2 production; motor activity; and deep body temperatures

Effects of reducing dietary crude protein and metabolic energy in ...

African Journals Online (AJOL)

The objective of this experiment was to determine the effects of a pure reduction in the dietary crude protein (CP) and metabolic energy (ME) contents on growth performance, nutrient digestibility, blood profile, faecal microflora and odour gas emission in weaned pigs. A total of 80 weaned piglets ((Landrace × Yorkshire) ...

Relationship between the effect of dietary fat on swimming endurance and energy metabolism in aged mice.

Science.gov (United States)

Zhang, Guihua; Shirai, Nobuya; Suzuki, Hiramitsu

2011-10-01

The aim of this study was to investigate the effect of different dietary fats on alterations in endurance, energy metabolism, and plasma levels of interleukin-6 (IL-6) and minerals in mice. Male mice (aged 58 weeks) were fed diets containing 6% safflower oil, fish oil, or lard for 12 weeks. Swimming time to exhaustion, energy metabolism, and plasma IL-6 levels were subsequently determined. Mice fed safflower oil exhibited a marked increase in swimming time compared to the baseline level. Mice fed lard exhibited a significant decrease in swimming time, while mice on a fish oil diet exhibited a small decrease in swimming time. The final swimming time of mice fed safflower oil was significantly longer than that of animals fed lard. This improvement in endurance with dietary safflower oil was accompanied by decreased accumulation of lactate and less glycogen depletion during swimming. In the safflower oil group, muscle carnitine palmitoyltransferase activity increased significantly after swimming, while the plasma non-esterified fatty acid concentration decreased significantly. A trend to increased plasma IL-6 levels was observed in sedentary animals on a safflower oil diet compared to those on a lard diet. These results suggest that dietary safflower oil improves the swimming endurance of aged mice to a greater extent than lard, and that this effect appears to involve glycogen sparing through increased fatty acid utilization. Copyright © 2011 S. Karger AG, Basel.

Impact of the gut microbiota on inflammation, obesity, and metabolic disease.

Science.gov (United States)

Boulangé, Claire L; Neves, Ana Luisa; Chilloux, Julien; Nicholson, Jeremy K; Dumas, Marc-Emmanuel

2016-04-20

The human gut harbors more than 100 trillion microbial cells, which have an essential role in human metabolic regulation via their symbiotic interactions with the host. Altered gut microbial ecosystems have been associated with increased metabolic and immune disorders in animals and humans. Molecular interactions linking the gut microbiota with host energy metabolism, lipid accumulation, and immunity have also been identified. However, the exact mechanisms that link specific variations in the composition of the gut microbiota with the development of obesity and metabolic diseases in humans remain obscure owing to the complex etiology of these pathologies. In this review, we discuss current knowledge about the mechanistic interactions between the gut microbiota, host energy metabolism, and the host immune system in the context of obesity and metabolic disease, with a focus on the importance of the axis that links gut microbes and host metabolic inflammation. Finally, we discuss therapeutic approaches aimed at reshaping the gut microbial ecosystem to regulate obesity and related pathologies, as well as the challenges that remain in this area.

Sleep fragmentation alters brain energy metabolism without modifying hippocampal electrophysiological response to novelty exposure.

Science.gov (United States)

Baud, Maxime O; Parafita, Julia; Nguyen, Audrey; Magistretti, Pierre J; Petit, Jean-Marie

2016-10-01

Sleep is viewed as a fundamental restorative function of the brain, but its specific role in neural energy budget remains poorly understood. Sleep deprivation dampens brain energy metabolism and impairs cognitive functions. Intriguingly, sleep fragmentation, despite normal total sleep duration, has a similar cognitive impact, and in this paper we ask the question of whether it may also impair brain energy metabolism. To this end, we used a recently developed mouse model of 2 weeks of sleep fragmentation and measured 2-deoxy-glucose uptake and glycogen, glucose and lactate concentration in different brain regions. In order to homogenize mice behaviour during metabolic measurements, we exposed them to a novel environment for 1 h. Using an intra-hippocampal electrode, we first showed that hippocampal electroencephalograph (EEG) response to exploration was unaltered by 1 or 14 days of sleep fragmentation. However, after 14 days, sleep fragmented mice exhibited a lower uptake of 2-deoxy-glucose in cortex and hippocampus and lower cortical lactate levels than control mice. Our results suggest that long-term sleep fragmentation impaired brain metabolism to a similar extent as total sleep deprivation without affecting the neuronal responsiveness of hippocampus to a novel environment. © 2016 European Sleep Research Society.

Sleep fragmentation alters brain energy metabolism without modifying hippocampal electrophysiological response to novelty exposure

KAUST Repository

Baud, Maxime O.

2016-05-03

© 2016 European Sleep Research Society. Sleep is viewed as a fundamental restorative function of the brain, but its specific role in neural energy budget remains poorly understood. Sleep deprivation dampens brain energy metabolism and impairs cognitive functions. Intriguingly, sleep fragmentation, despite normal total sleep duration, has a similar cognitive impact, and in this paper we ask the question of whether it may also impair brain energy metabolism. To this end, we used a recently developed mouse model of 2 weeks of sleep fragmentation and measured 2-deoxy-glucose uptake and glycogen, glucose and lactate concentration in different brain regions. In order to homogenize mice behaviour during metabolic measurements, we exposed them to a novel environment for 1 h. Using an intra-hippocampal electrode, we first showed that hippocampal electroencephalograph (EEG) response to exploration was unaltered by 1 or 14 days of sleep fragmentation. However, after 14 days, sleep fragmented mice exhibited a lower uptake of 2-deoxy-glucose in cortex and hippocampus and lower cortical lactate levels than control mice. Our results suggest that long-term sleep fragmentation impaired brain metabolism to a similar extent as total sleep deprivation without affecting the neuronal responsiveness of hippocampus to a novel environment.

High energy physics research. Final technical report, 1957--1994

International Nuclear Information System (INIS)

Williams, H.H.

1995-01-01

This is the final technical report to the Department of Energy on High Energy Physics at the University of Pennsylvania. It discusses research conducted in the following areas: neutrino astrophysics and cosmology; string theory; electroweak and collider physics; supergravity; cp violation and baryogenesis; particle cosmology; collider detector at Fermilab; the sudbury neutrino observatory; B-physics; particle physics in nuclei; and advanced electronics and detector development

High energy physics research. Final technical report, 1957--1994

Energy Technology Data Exchange (ETDEWEB)

Williams, H.H.

1995-10-01

This is the final technical report to the Department of Energy on High Energy Physics at the University of Pennsylvania. It discusses research conducted in the following areas: neutrino astrophysics and cosmology; string theory; electroweak and collider physics; supergravity; cp violation and baryogenesis; particle cosmology; collider detector at Fermilab; the sudbury neutrino observatory; B-physics; particle physics in nuclei; and advanced electronics and detector development.

Dysregulated metabolism contributes to oncogenesis

Science.gov (United States)

Hirschey, Matthew D.; DeBerardinis, Ralph J.; Diehl, Anna Mae E.; Drew, Janice E.; Frezza, Christian; Green, Michelle F.; Jones, Lee W.; Ko, Young H.; Le, Anne; Lea, Michael A.; Locasale, Jason W.; Longo, Valter D.; Lyssiotis, Costas A.; McDonnell, Eoin; Mehrmohamadi, Mahya; Michelotti, Gregory; Muralidhar, Vinayak; Murphy, Michael P.; Pedersen, Peter L.; Poore, Brad; Raffaghello, Lizzia; Rathmell, Jeffrey C.; Sivanand, Sharanya; Vander Heiden, Matthew G.; Wellen, Kathryn E.

2015-01-01

Cancer is a disease characterized by unrestrained cellular proliferation. In order to sustain growth, cancer cells undergo a complex metabolic rearrangement characterized by changes in metabolic pathways involved in energy production and biosynthetic processes. The relevance of the metabolic transformation of cancer cells has been recently included in the updated version of the review “Hallmarks of Cancer”, where the dysregulation of cellular metabolism was included as an emerging hallmark. While several lines of evidence suggest that metabolic rewiring is orchestrated by the concerted action of oncogenes and tumor suppressor genes, in some circumstances altered metabolism can play a primary role in oncogenesis. Recently, mutations of cytosolic and mitochondrial enzymes involved in key metabolic pathways have been associated with hereditary and sporadic forms of cancer. Together, these results suggest that aberrant metabolism, once seen just as an epiphenomenon of oncogenic reprogramming, plays a key role in oncogenesis with the power to control both genetic and epigenetic events in cells. In this review, we discuss the relationship between metabolism and cancer, as part of a larger effort to identify a broad-spectrum of therapeutic approaches. We focus on major alterations in nutrient metabolism and the emerging link between metabolism and epigenetics. Finally, we discuss potential strategies to manipulate metabolism in cancer and tradeoffs that should be considered. More research on the suite of metabolic alterations in cancer holds the potential to discover novel approaches to treat it. PMID:26454069

The development of sectoral final and basic energy demand in the Federal Republic of Germany

International Nuclear Information System (INIS)

Reents, H.

1977-08-01

The detailed knowledge of the demand structures and their determining factors is an important precondition for estimating the possible developments of future energy demand. In this report the past developments of the final and basic energy demand in the different demand categories private households, commercial sector, industry and transportation will be analyzed. The demonstrated relations are the basis for a final energy demand model. With the help of this model a scenario of the future development of the final energy demand in the different sectors will be built. It is the aim of this scenario to show, how alternative actions (insulation, gas-heat pump) influence the future development of the final energy demand. (orig.) [de

Thyroid hormones correlate with resting metabolic rate, not daily energy expenditure, in two charadriiform seabirds

Directory of Open Access Journals (Sweden)

Kyle H. Elliott

2013-04-01

Thyroid hormones affect in vitro metabolic intensity, increase basal metabolic rate (BMR in the lab, and are sometimes correlated with basal and/or resting metabolic rate (RMR in a field environment. Given the difficulty of measuring metabolic rate in the field—and the likelihood that capture and long-term restraint necessary to measure metabolic rate in the field jeopardizes other measurements—we examined the possibility that circulating thyroid hormone levels were correlated with RMR in two free-ranging bird species with high levels of energy expenditure (the black-legged kittiwake, Rissa tridactyla, and thick-billed murre, Uria lomvia. Because BMR and daily energy expenditure (DEE are purported to be linked, we also tested for a correlation between thyroid hormones and DEE. We examined the relationships between free and bound levels of the thyroid hormones thyroxine (T4 and triiodothyronine (T3 with DEE and with 4-hour long measurements of post-absorptive and thermoneutral resting metabolism (resting metabolic rate; RMR. RMR but not DEE increased with T3 in both species; both metabolic rates were independent of T4. T3 and T4 were not correlated with one another. DEE correlated with body mass in kittiwakes but not in murres, presumably owing to the larger coefficient of variation in body mass during chick rearing for the more sexually dimorphic kittiwakes. We suggest T3 provides a good proxy for resting metabolism but not DEE in these seabird species.

Sleep fragmentation alters brain energy metabolism without modifying hippocampal electrophysiological response to novelty exposure

KAUST Repository

Baud, Maxime O.; Parafita, Julia; Nguyen, Audrey; Magistretti, Pierre J.; Petit, Jean-Marie

2016-01-01

© 2016 European Sleep Research Society. Sleep is viewed as a fundamental restorative function of the brain, but its specific role in neural energy budget remains poorly understood. Sleep deprivation dampens brain energy metabolism and impairs

Catalonia's energy metabolism: Using the MuSIASEM approach at different scales

International Nuclear Information System (INIS)

Ramos-Martin, Jesus; Canellas-Bolta, Silvia; Giampietro, Mario; Gamboa, Gonzalo

2009-01-01

This paper applies the so-called Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM), based on Georgescu-Roegen's fund-flow model, to the Spanish region of Catalonia. It arrives to the conclusion that within the context of the end of cheap oil, the current development model of the Catalan economy, based on the growth of low-productivity sectors such as services and construction, must be changed. The change is needed not only because of the increasing scarcity of affordable energy and the increasing environmental impact of present development, but also because of the aging population. Moreover, the situation experienced by Catalonia is similar to that of other European countries and many other developed countries. This implies that we can expect a wave of major structural changes in the economy of developed countries worldwide. To make things more challenging, according to current trends, the energy intensity and exosomatic energy metabolism of Catalonia will keep increasing in the near future. To avoid a reduction in the standard of living of Catalans due to a reduction in the available energy it is important that the Government of Catalonia implement major adjustments and conservation efforts in both the household and paid-work sectors.

Genotype by energy expenditure interaction with metabolic syndrome traits: the Portuguese healthy family study.

Directory of Open Access Journals (Sweden)

Daniel M V Santos

Full Text Available Moderate-to-high levels of physical activity are established as preventive factors in metabolic syndrome development. However, there is variability in the phenotypic expression of metabolic syndrome under distinct physical activity conditions. In the present study we applied a Genotype X Environment interaction method to examine the presence of GxEE interaction in the phenotypic expression of metabolic syndrome. A total of 958 subjects, from 294 families of The Portuguese Healthy Family study, were included in the analysis. Total daily energy expenditure was assessed using a 3 day physical activity diary. Six metabolic syndrome related traits, including waist circumference, systolic blood pressure, glucose, HDL cholesterol, total cholesterol and triglycerides, were measured and adjusted for age and sex. GxEE examination was performed on SOLAR 4.3.1. All metabolic syndrome indicators were significantly heritable. The GxEE interaction model fitted the data better than the polygenic model (p<0.001 for waist circumference, systolic blood pressure, glucose, total cholesterol and triglycerides. For waist circumference, glucose, total cholesterol and triglycerides, the significant GxEE interaction was due to rejection of the variance homogeneity hypothesis. For waist circumference and glucose, GxEE was also significant by the rejection of the genetic correlation hypothesis. The results showed that metabolic syndrome traits expression is significantly influenced by the interaction established between total daily energy expenditure and genotypes. Physical activity may be considered an environmental variable that promotes metabolic differences between individuals that are distinctively active.

Computational Modeling of Fluctuations in Energy and Metabolic Pathways of Methanogenic Archaea

Energy Technology Data Exchange (ETDEWEB)

Luthey-Schulten, Zaida [Univ. of Illinois, Urbana-Champaign, IL (United States). Dept. of Chemistry; Carl R. Woese Inst. for Genomic Biology

2017-01-04

The methanogenic archaea, anaerobic microbes that convert CO2 and H2 and/or other small organic fermentation products into methane, play an unusually large role in the global carbon cycle. As they perform the final step in the anaerobic breakdown of biomass, methanogens are a biogenic source of an estimated one billion tons methane each year. Depending on the location, produced methane can be considered as either a greenhouse gas (agricultural byproduct), sequestered carbon storage (methane hydrate deposits), or a potential energy source (organic wastewater treatment). These microbes therefore represent an important target for biotechnology applications. Computational models of methanogens with predictive power are useful aids in the adaptation of methanogenic systems, but need to connect processes of wide-ranging time and length scales. In this project, we developed several computational methodologies for modeling the dynamic behavior of entire cells that connects stochastic reaction-diffusion dynamics of individual biochemical pathways with genome-scale modeling of metabolic networks. While each of these techniques were in the realm of well-defined computational methods, here we integrated them to develop several entirely new approaches to systems biology. The first scientific aim of the project was to model how noise in a biochemical pathway propagates into cellular phenotypes. Genetic circuits have been optimized by evolution to regulate molecular processes despite stochastic noise, but the effect of such noise on a cellular biochemical networks is currently unknown. An integrated stochastic/systems model of Escherichia coli species was created to analyze how noise in protein expression gives—and therefore noise in metabolic fluxes—gives rise to multiple cellular phenotype in isogenic population. After the initial work developing and validating methods that allow characterization of the heterogeneity in the model organism E. coli, the project shifted toward

Neutron emission effects on final fragments mass and kinetic energy distribution from low energy fission of {sup 234}U

Energy Technology Data Exchange (ETDEWEB)

Montoya, M.; Rojas, J. [Instituto Peruano de Energia Nuclear, Av. Canada 1470, Lima 41 (Peru); Lobato, I. [Facultad de Ciencias, Universidad Nacional de Ingenieria, Av. Tupac Amaru 210, Apartado Postal 31-139, Lima (Peru)]. e-mail: mmontoya@ipen.gob.pe

2008-07-01

The standard deviation of the final kinetic energy distribution ({sigma}{sub e}) as a function of mass of final fragments (m) from low energy fission of {sup 234}U, measured with the Lohengrin spectrometer by Belhafaf et al., presents a peak around m = 109 and another around m = 122. The authors attribute the first peak to the evaporation of a large number of neutrons around the corresponding mass number, i.e. there is no peak on the standard deviation of the primary kinetic energy distribution ({sigma}{sub E}) as a function of primary fragment mass (A). The second peak is attributed to a real peak on {sigma}{sub E}(A). However, theoretical calculations related to primary distributions made by H.R. Faust and Z. Bao do not suggest any peak on {sigma}{sub E}(A). In order to clarify this apparent controversy, we have made a numerical experiment in which the masses and the kinetic energy of final fragments are calculated, assuming an initial distribution of the kinetic energy without structures on the standard deviation as function of fragment mass. As a result we obtain a pronounced peak on {sigma}{sub e} (m) curve around m = 109, a depletion from m = 121 to m = 129, and an small peak around m = 122, which is not as great as that measured by Belhafaf et al. Our simulation also reproduces the experimental results on the yield of the final mass Y(m), the average number of emitted neutrons as a function of the provisional mass (calculated from the values of the final kinetic energy of the complementary fragments) and the average value of fragment kinetic energy as a function of the final mass. From our results we conclude that there are no peaks on the {sigma}{sub E} (A) curve, and the observed peaks on {sigma}{sub e} (m) are due to the emitted neutron multiplicity and the variation of the average fragment kinetic energy as a function of primary fragment mass. (Author)

An Integrative Approach to Energy Carbon and Redox Metabolism In Cyanobacterium Synechocystis

Energy Technology Data Exchange (ETDEWEB)

Dr. Ross Overbeek

2003-06-30

The main objectives for the first year were to produce a detailed metabolic reconstruction of synechocystis sp.pcc6803 especially in interrelated arrears of photosynthesis respiration and central carbon metabolism to support a more complete understanding and modeling of this organism. Additionally, IG, Inc. provided detailed bioinformatic analysis of selected functional systems related to carbon and energy generation and utilization, and of the corresponding pathways functional roles and individual genes to support wet lab experiments by collaborators.

Energy metabolism of overweight women before, during and after weight reduction, assessed by indirect calorimetry

NARCIS (Netherlands)

Groot, de C.P.G.M.

1988-01-01

Previous studies had suggested that periods of low energy intake evoke compensatory adaptations in energy metabolism, which retard weight loss, and promote weight regain when energy intake returns to normal. The aim of this thesis was to investigate whether a slimming (low-energy) diet based on

Final cooling for a high-energy high-luminosity lepton collider

Science.gov (United States)

Neuffer, D.; Sayed, H.; Acosta, J.; Hart, T.; Summers, D.

2017-07-01

A high-energy muon collider requires a "final cooling" system that reduces transverse emittance by a factor of ~ 10, while allowing the longitudinal emittance to increase. The baseline approach has low-energy transverse cooling within high-field solenoids, with strong longitudinal heating. This approach and its recent simulation are discussed. Alternative approaches, which more explicitly include emittance exchange are also presented. Round-to-flat beam transform, transverse slicing, and longitudinal bunch coalescence are possible components of an alternative approach. Wedge-based emittance exchange could provide much of the required transverse cooling with longitudinal heating. Li-lens and quadrupole focusing systems could also provide much of the required final cooling.

Final Cooling for a High-Energy High-Luminosity Lepton Collider

Energy Technology Data Exchange (ETDEWEB)

Neuffer, David [Fermilab; Sayed, H. [Brookhaven; Hart, T. [Mississippi U.; Summers, D. [Mississippi U.

2015-12-03

A high-energy muon collider scenario require a “final cooling” system that reduces transverse emittance by a factor of ~10 while allowing longitudinal emittance increase. The baseline approach has low-energy transverse cooling within high-field solenoids, with strong longitudinal heating. This approach and its recent simulation are discussed. Alternative approaches which more explicitly include emittance exchange are also presented. Round-to-flat beam transform, transverse slicing, and longitudinal bunch coalescence are possible components of an alternative approach. Wedge-based emittance exchange could provide much of the required transverse cooling with longitudinal heating. Li-lens and quadrupole focusing systems could also provide much of the required final cooling.

Body size, body composition, and metabolic profile explain higher energy expenditure in overweight children

Science.gov (United States)

Lower relative rates of energy expenditure (EE), increased energetic efficiency, and altered fuel utilization purportedly associated with obesity have not been demonstrated indisputably in overweight children. We hypothesized that differences in energy metabolism between nonoverweight and overweight...

National energy peak leveling program (NEPLP). Final report

Energy Technology Data Exchange (ETDEWEB)

None

1977-12-01

This three-volume report is responsive to the requirements of Contract E (04-3)-1152 to provide a detailed methodology, to include management, technology, and socio-economic aspects, of a voluntary community program of computer-assisted peak load leveling and energy conservation in commercial community facilities. The demonstration project established proof-of-concept in reducing the kW-demand peak by the unofficial goal of 10%, with concurrent kWh savings. This section of the three volume report is a final report appendix with information on the National Energy Peak Leveling Program (NEPLP).

Rhabdomyosarcoma cells show an energy producing anabolic metabolic phenotype compared with primary myocytes

Directory of Open Access Journals (Sweden)

Higashi Richard M

2008-10-01

Full Text Available Abstract Background The functional status of a cell is expressed in its metabolic activity. We have applied stable isotope tracing methods to determine the differences in metabolic pathways in proliferating Rhabdomysarcoma cells (Rh30 and human primary myocytes in culture. Uniformly 13C-labeled glucose was used as a source molecule to follow the incorporation of 13C into more than 40 marker metabolites using NMR and GC-MS. These include metabolites that report on the activity of glycolysis, Krebs' cycle, pentose phosphate pathway and pyrimidine biosynthesis. Results The Rh30 cells proliferated faster than the myocytes. Major differences in flux through glycolysis were evident from incorporation of label into secreted lactate, which accounts for a substantial fraction of the glucose carbon utilized by the cells. Krebs' cycle activity as determined by 13C isotopomer distributions in glutamate, aspartate, malate and pyrimidine rings was considerably higher in the cancer cells than in the primary myocytes. Large differences were also evident in de novo biosynthesis of riboses in the free nucleotide pools, as well as entry of glucose carbon into the pyrimidine rings in the free nucleotide pool. Specific labeling patterns in these metabolites show the increased importance of anaplerotic reactions in the cancer cells to maintain the high demand for anabolic and energy metabolism compared with the slower growing primary myocytes. Serum-stimulated Rh30 cells showed higher degrees of labeling than serum starved cells, but they retained their characteristic anabolic metabolism profile. The myocytes showed evidence of de novo synthesis of glycogen, which was absent in the Rh30 cells. Conclusion The specific 13C isotopomer patterns showed that the major difference between the transformed and the primary cells is the shift from energy and maintenance metabolism in the myocytes toward increased energy and anabolic metabolism for proliferation in the Rh30 cells

Fluvoxamine alters the activity of energy metabolism enzymes in the brain

Directory of Open Access Journals (Sweden)

Gabriela K. Ferreira

2014-09-01

Full Text Available Objective: Several studies support the hypothesis that metabolism impairment is involved in the pathophysiology of depression and that some antidepressants act by modulating brain energy metabolism. Thus, we evaluated the activity of Krebs cycle enzymes, the mitochondrial respiratory chain, and creatine kinase in the brain of rats subjected to prolonged administration of fluvoxamine. Methods: Wistar rats received daily administration of fluvoxamine in saline (10, 30, and 60 mg/kg for 14 days. Twelve hours after the last administration, rats were killed by decapitation and the prefrontal cortex, cerebral cortex, hippocampus, striatum, and cerebellum were rapidly isolated. Results: The activities of citrate synthase, malate dehydrogenase, and complexes I, II-III, and IV were decreased after prolonged administration of fluvoxamine in rats. However, the activities of complex II, succinate dehydrogenase, and creatine kinase were increased. Conclusions: Alterations in activity of energy metabolism enzymes were observed in most brain areas analyzed. Thus, we suggest that the decrease in citrate synthase, malate dehydrogenase, and complexes I, II-III, and IV can be related to adverse effects of pharmacotherapy, but long-term molecular adaptations cannot be ruled out. In addition, we demonstrated that these changes varied according to brain structure or biochemical analysis and were not dose-dependent.

A20 modulates lipid metabolism and energy production to promote liver regeneration.

Directory of Open Access Journals (Sweden)

Scott M Damrauer

2011-03-01

Full Text Available Liver regeneration is clinically of major importance in the setting of liver injury, resection or transplantation. We have demonstrated that the NF-κB inhibitory protein A20 significantly improves recovery of liver function and mass following extended liver resection (LR in mice. In this study, we explored the Systems Biology modulated by A20 following extended LR in mice.We performed transcriptional profiling using Affymetrix-Mouse 430.2 arrays on liver mRNA retrieved from recombinant adenovirus A20 (rAd.A20 and rAd.βgalactosidase treated livers, before and 24 hours after 78% LR. A20 overexpression impacted 1595 genes that were enriched for biological processes related to inflammatory and immune responses, cellular proliferation, energy production, oxidoreductase activity, and lipid and fatty acid metabolism. These pathways were modulated by A20 in a manner that favored decreased inflammation, heightened proliferation, and optimized metabolic control and energy production. Promoter analysis identified several transcriptional factors that implemented the effects of A20, including NF-κB, CEBPA, OCT-1, OCT-4 and EGR1. Interactive scale-free network analysis captured the key genes that delivered the specific functions of A20. Most of these genes were affected at basal level and after resection. We validated a number of A20's target genes by real-time PCR, including p21, the mitochondrial solute carriers SLC25a10 and SLC25a13, and the fatty acid metabolism regulator, peroxisome proliferator activated receptor alpha. This resulted in greater energy production in A20-expressing livers following LR, as demonstrated by increased enzymatic activity of cytochrome c oxidase, or mitochondrial complex IV.This Systems Biology-based analysis unravels novel mechanisms supporting the pro-regenerative function of A20 in the liver, by optimizing energy production through improved lipid/fatty acid metabolism, and down-regulated inflammation. These findings

Hypothalamic Energy Metabolism Is Impaired By Doxorubicin Independently Of Inflammation In Non-tumour-bearing Rats.

OpenAIRE

Antunes, Barbara M M; Lira, Fabio Santos; Pimentel, Gustavo Duarte; Rosa Neto, José Cesar; Esteves, Andrea Maculano; Oyama, Lila Missae; de Souza, Cláudio Teodoro; Gonçalves, Cinara Ludvig; Streck, Emilio Luiz; Rodrigues, Bruno; dos Santos, Ronaldo Vagner; de Mello, Marco Túlio

2016-01-01

We sought to explore the effects of doxorubicin on inflammatory profiles and energy metabolism in the hypothalamus of rats. To investigate these effects, we formed two groups: a control (C) group and a Doxorubicin (DOXO) group. Sixteen rats were randomly assigned to either the control (C) or DOXO groups. The hypothalamus was collected. The levels of interleukin (IL)-1β, IL-6, IL-10, TNF-α and energy metabolism (malate dehydrogenase, complex I and III activities) were analysed in the hypothala...

[Metabolic myopathies].

Science.gov (United States)

Papazian, Óscar; Rivas-Chacón, Rafael

2013-09-06

To review the metabolic myopathies manifested only by crisis of myalgias, cramps and rigidity of the muscles with decreased voluntary contractions and normal inter crisis neurologic examination in children and adolescents. These metabolic myopathies are autosomic recessive inherited enzymatic deficiencies of the carbohydrates and lipids metabolisms. The end result is a reduction of intra muscle adenosine triphosphate, mainly through mitochondrial oxidative phosphorylation, with decrease of available energy for muscle contraction. The one secondary to carbohydrates intra muscle metabolism disorders are triggered by high intensity brief (fatty acids metabolism disorders are triggered by low intensity prolonged (> 10 min) exercises. The conditions in the first group in order of decreasing frequency are the deficiencies of myophosforilase (GSD V), muscle phosphofructokinase (GSD VII), phosphoglycerate mutase 1 (GSD X) and beta enolase (GSD XIII). The conditions in the second group in order of decreasing frequency are the deficiencies of carnitine palmitoyl transferase II and very long chain acyl CoA dehydrogenase. The differential characteristics of patients in each group and within each group will allow to make the initial presumptive clinical diagnosis in the majority and then to order only the necessary tests to achieve the final diagnosis. Treatment during the crisis includes hydration, glucose and alkalinization of urine if myoglobin in blood and urine are elevated. Prevention includes avoiding exercise which may induce the crisis and fasting. The prognosis is good with the exception of rare cases of acute renal failure due to hipermyoglobinemia because of severe rabdomyolisis.

Human longevity is characterised by high thyroid stimulating hormone secretion without altered energy metabolism.

Science.gov (United States)

Jansen, S W; Akintola, A A; Roelfsema, F; van der Spoel, E; Cobbaert, C M; Ballieux, B E; Egri, P; Kvarta-Papp, Z; Gereben, B; Fekete, C; Slagboom, P E; van der Grond, J; Demeneix, B A; Pijl, H; Westendorp, R G J; van Heemst, D

2015-06-19

Few studies have included subjects with the propensity to reach old age in good health, with the aim to disentangle mechanisms contributing to staying healthier for longer. The hypothalamic-pituitary-thyroid (HPT) axis maintains circulating levels of thyroid stimulating hormone (TSH) and thyroid hormone (TH) in an inverse relationship. Greater longevity has been associated with higher TSH and lower TH levels, but mechanisms underlying TSH/TH differences and longevity remain unknown. The HPT axis plays a pivotal role in growth, development and energy metabolism. We report that offspring of nonagenarians with at least one nonagenarian sibling have increased TSH secretion but similar bioactivity of TSH and similar TH levels compared to controls. Healthy offspring and spousal controls had similar resting metabolic rate and core body temperature. We propose that pleiotropic effects of the HPT axis may favour longevity without altering energy metabolism.

Basal metabolic rate in relation to body composition and daily energy expenditure in the field vole, Microtus agrestis

NARCIS (Netherlands)

Meerlo, P; Bolle, L; Visser, GH; Masman, D; Daan, S

1997-01-01

Basal metabolic rate in the field vole (Microtus agrestis) was studied in relation to body composition and daily energy expenditure in the field Daily energy expenditure was measured by means of doubly labelled water ((D2O)-O-18). In the same individuals, basal metabolic rate was subsequently

Impact of hypothalamic reactive oxygen species in the control of energy metabolism and food intake

Directory of Open Access Journals (Sweden)

Anne eDrougard

2015-02-01

Full Text Available Hypothalamus is a key area involved in the control of metabolism and food intake via the integrations of numerous signals (hormones, neurotransmitters, metabolites from various origins. These factors modify hypothalamic neurons activity and generate adequate molecular and behavioral responses to control energy balance. In this complex integrative system, a new concept has been developed in recent years, that includes reactive oxygen species (ROS as a critical player in energy balance. ROS are known to act in many signaling pathways in different peripheral organs, but also in hypothalamus where they regulate food intake and metabolism by acting on different types of neurons, including proopiomelanocortin (POMC and agouti-related protein (AgRP/neuropeptide Y (NPY neurons. Hypothalamic ROS release is under the influence of different factors such as pancreatic and gut hormones, adipokines (leptin, apelin,..., neurotransmitters and nutrients (glucose, lipids,.... The sources of ROS production are multiple including NADPH oxidase, but also the mitochondria which is considered as the main ROS producer in the brain. ROS are considered as signaling molecules, but conversely impairment of this neuronal signaling ROS pathway contributes to alterations of autonomic nervous system and neuroendocrine function, leading to metabolic diseases such as obesity and type 2 diabetes.In this review we focus our attention on factors that are able to modulate hypothalamic ROS release in order to control food intake and energy metabolism, and whose deregulations could participate to the development of pathological conditions. This novel insight reveals an original mechanism in the hypothalamus that controls energy balance and identify hypothalamic ROS signaling as a potential therapeutic strategy to treat metabolic disorders.

Impact of hypothalamic reactive oxygen species in the regulation of energy metabolism and food intake.

Science.gov (United States)

Drougard, Anne; Fournel, Audren; Valet, Philippe; Knauf, Claude

2015-01-01

Hypothalamus is a key area involved in the control of metabolism and food intake via the integrations of numerous signals (hormones, neurotransmitters, metabolites) from various origins. These factors modify hypothalamic neurons activity and generate adequate molecular and behavioral responses to control energy balance. In this complex integrative system, a new concept has been developed in recent years, that includes reactive oxygen species (ROS) as a critical player in energy balance. ROS are known to act in many signaling pathways in different peripheral organs, but also in hypothalamus where they regulate food intake and metabolism by acting on different types of neurons, including proopiomelanocortin (POMC) and agouti-related protein (AgRP)/neuropeptide Y (NPY) neurons. Hypothalamic ROS release is under the influence of different factors such as pancreatic and gut hormones, adipokines (leptin, apelin,…), neurotransmitters and nutrients (glucose, lipids,…). The sources of ROS production are multiple including NADPH oxidase, but also the mitochondria which is considered as the main ROS producer in the brain. ROS are considered as signaling molecules, but conversely impairment of this neuronal signaling ROS pathway contributes to alterations of autonomic nervous system and neuroendocrine function, leading to metabolic diseases such as obesity and type 2 diabetes. In this review we focus our attention on factors that are able to modulate hypothalamic ROS release in order to control food intake and energy metabolism, and whose deregulations could participate to the development of pathological conditions. This novel insight reveals an original mechanism in the hypothalamus that controls energy balance and identify hypothalamic ROS signaling as a potential therapeutic strategy to treat metabolic disorders.

Practicing Tai Chi had lower energy metabolism than walking but similar health benefits in terms of aerobic fitness, resting energy expenditure, body composition and self-perceived physical health.

Science.gov (United States)

Hui, Stanley Sai-Chuen; Xie, Yao Jie; Woo, Jean; Kwok, Timothy Chi-Yui

2016-08-01

To examine the effects of Tai Chi and walking training on aerobic fitness, resting energy expenditure (REE), body composition, and quality of life; as well as analyzing the energy metabolism during exercises, to determine which one had better advantage in improving health status. Three hundred seventy-four middle-aged Chinese subjects who were recruited from nine geographic areas in Sha Tin were randomized into Tai Chi, walking, or control groups at area level. The 12-week (45min per day, 5days per week) Tai Chi or brisk walking training were conducted in respective intervention groups. Measures were performed at baseline and end of trial. Another 30 subjects were recruited to compare the energy metabolism between practicing Tai Chi and walking. The between-group difference of VO2max was 3.3ml/min/kg for Tai Chi vs. control and 3.7ml/min/kg for walking vs. control (both Pwalking. Regarding to energy metabolism test, the self-paced walking produced approximately 46% higher metabolic costs than Tai Chi. Practicing Tai Chi consumes a smaller amount of energy metabolism but similar health benefits as self-paced brisk walking. Copyright © 2016. Published by Elsevier Ltd.

Energy Metabolism of the Brain, Including the Cooperation between Astrocytes and Neurons, Especially in the Context of Glycogen Metabolism.

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Falkowska, Anna; Gutowska, Izabela; Goschorska, Marta; Nowacki, Przemysław; Chlubek, Dariusz; Baranowska-Bosiacka, Irena

2015-10-29

Glycogen metabolism has important implications for the functioning of the brain, especially the cooperation between astrocytes and neurons. According to various research data, in a glycogen deficiency (for example during hypoglycemia) glycogen supplies are used to generate lactate, which is then transported to neighboring neurons. Likewise, during periods of intense activity of the nervous system, when the energy demand exceeds supply, astrocyte glycogen is immediately converted to lactate, some of which is transported to the neurons. Thus, glycogen from astrocytes functions as a kind of protection against hypoglycemia, ensuring preservation of neuronal function. The neuroprotective effect of lactate during hypoglycemia or cerebral ischemia has been reported in literature. This review goes on to emphasize that while neurons and astrocytes differ in metabolic profile, they interact to form a common metabolic cooperation.

High Glucose-Induced Cardiomyocyte Death May Be Linked to Unbalanced Branched-Chain Amino Acids and Energy Metabolism

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Xi Zhang

2018-04-01

Full Text Available High glucose-induced cardiomyocyte death is a common symptom in advanced-stage diabetic patients, while its metabolic mechanism is still poorly understood. The aim of this study was to explore metabolic changes in high glucose-induced cardiomyocytes and the heart of streptozotocin-induced diabetic rats by 1H-NMR-based metabolomics. We found that high glucose can promote cardiomyocyte death both in vitro and in vivo studies. Metabolomic results show that several metabolites exhibited inconsistent variations in vitro and in vivo. However, we also identified a series of common metabolic changes, including increases in branched-chain amino acids (BCAAs: leucine, isoleucine and valine as well as decreases in aspartate and creatine under high glucose condition. Moreover, a reduced energy metabolism could also be a common metabolic characteristic, as indicated by decreases in ATP in vitro as well as AMP, fumarate and succinate in vivo. Therefore, this study reveals that a decrease in energy metabolism and an increase in BCAAs metabolism could be implicated in high glucose-induced cardiomyocyte death.

Energy final consumption projection - 1985/2005 - basic scenery - Minas Gerais State

International Nuclear Information System (INIS)

1989-03-01

A projection of the final energy consumption study for the Minas Gerais State until 2005 year is presented. The conclusion of this projection shows a increasing of 108,8% for the total energy. The industries will be response for 62,0% and the transport sector will use 20,7% of the total energy in 2005. (L.J.C.)

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

Science.gov (United States)

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

Frequency of feeding, weight reduction and energy metabolism.

Science.gov (United States)

Verboeket-van de Venne, W P; Westerterp, K R

1993-01-01

A study was conducted to investigate the effect of feeding frequency on the rate and composition of weight loss and 24 h energy metabolism in moderately obese women on a 1000 kcal/day diet. During four consecutive weeks fourteen female adults (age 20-58 years, BMI 25.4-34.9 kg/m2) restricted their food intake to 1000 kcal/day. Seven subjects consumed the diet in two meals daily (gorging pattern), the others consumed the diet in three to five meals (nibbling pattern). Body mass and body composition, obtained by deuterium dilution, were measured at the start of the experiment and after two and four weeks of dieting. Sleeping metabolic rate (SMR) was measured at the same time intervals using a respiration chamber. At the end of the experiment 24 h energy expenditure (24 h EE) and diet-induced thermogenesis (DIT) were assessed by a 36 h stay in the respiration chamber. There was no significant effect of the feeding frequency on the rate of weight loss, fat mass loss or fat-free mass loss. Furthermore, fat mass and fat-free mass contributed equally to weight loss in subjects on both gorging and nibbling diet. Feeding frequency had no significant effect on SMR after two or four weeks of dieting. The decrease in SMR after four weeks was significantly greater in subjects on the nibbling diet. 24 h EE and DIT were not significantly different between the two feeding regimens.(ABSTRACT TRUNCATED AT 250 WORDS)

Energy metabolism and inflammation in brain aging and Alzheimer's disease.

Science.gov (United States)

Yin, Fei; Sancheti, Harsh; Patil, Ishan; Cadenas, Enrique

2016-11-01

The high energy demand of the brain renders it sensitive to changes in energy fuel supply and mitochondrial function. Deficits in glucose availability and mitochondrial function are well-known hallmarks of brain aging and are particularly accentuated in neurodegenerative disorders such as Alzheimer's disease. As important cellular sources of H 2 O 2 , mitochondrial dysfunction is usually associated with altered redox status. Bioenergetic deficits and chronic oxidative stress are both major contributors to cognitive decline associated with brain aging and Alzheimer's disease. Neuroinflammatory changes, including microglial activation and production of inflammatory cytokines, are observed in neurodegenerative diseases and normal aging. The bioenergetic hypothesis advocates for sequential events from metabolic deficits to propagation of neuronal dysfunction, to aging, and to neurodegeneration, while the inflammatory hypothesis supports microglia activation as the driving force for neuroinflammation. Nevertheless, growing evidence suggests that these diverse mechanisms have redox dysregulation as a common denominator and connector. An independent view of the mechanisms underlying brain aging and neurodegeneration is being replaced by one that entails multiple mechanisms coordinating and interacting with each other. This review focuses on the alterations in energy metabolism and inflammatory responses and their connection via redox regulation in normal brain aging and Alzheimer's disease. Interaction of these systems is reviewed based on basic research and clinical studies. Copyright © 2016 Elsevier Inc. All rights reserved.

A review of some metabolic changes in protein-energy malnutrition.

Science.gov (United States)

Akuyam, S A

2007-06-01

Protein-energy malnutrition (PEM) is a major public health problem in the tropical and subtropical regions of the world and often arises during protein and / or energy deficit due to nutritional inadequacy, infections and poor socio-economic and environmental conditions. It is the most common nutritional disorder affecting children in developing countries and the third most common disease of childhood in such countries. PEM has a lasting effect on immune functions, growth and development of children, learning ability, social adjustment, work efficiency and productivity of labour. It seems that many deaths from PEM occur as a result of outdated clinical practices and that improving these practices reduces the rate of morbidity and mortality. This paper reviews various metabolic changes in protein-energy malnutrition (PEM). It gives an overview of the theoretical basis for the understanding of the biochemical derangements in PEM. It aims at stimulating the paediatricians and clinical chemists to read more on the recent advances in this broad subject with the view to improving the understanding of the current laboratory investigation of PEM. This review demonstrates that the metabolic changes in PEM include water and electrolytes imbalance, amino acids and proteins deficiencies, carbohydrates and energy deficiencies, hypolipidaemias, hypolipoproteinaemias, hormonal imbalance, deficiency of anti-oxidant vitamins and enzymes, depression of cell-mediated immune complexes and decrease in amino acids and trace elements in skin and hair. The review therefore suggests that assessment of these conditions in PEM patients could improve the management of this group of patients and hence reduce the rate of morbidity and mortality from PEM.

Differential regulation of metabolic parameters by energy deficit and hunger.

Science.gov (United States)

Kitka, Tamás; Tuza, Sebestyén; Varga, Balázs; Horváth, Csilla; Kovács, Péter

2015-10-01

Hypocaloric diet decreases both energy expenditure (EE) and respiratory exchange rate (RER), affecting the efficacy of dieting inversely. Energy deficit and hunger may be modulated separately both in human and animal studies by drug treatment or food restriction. Thus it is important to separate the effects of energy deficit and hunger on EE and RER. Three parallel and analogous experiments were performed using three pharmacologically distinct anorectic drugs: rimonabant, sibutramine and tramadol. Metabolic parameters of vehicle- and drug-treated and pair-fed diet-induced obese mice from the three experiments underwent common statistical analysis to identify effects independent of the mechanisms of action. Diet-induced obesity (DIO) test of tramadol was also performed to examine its anti-obesity efficacy. RER was decreased similarly by drug treatments and paired feeding throughout the experiment irrespective of the cause of reduced food intake. Contrarily, during the passive phase, EE was decreased more by paired feeding than by both vehicle and drug treatment irrespective of the drug used. In the active phase, EE was influenced by the pharmacological mechanisms of action. Tramadol decreased body weight in the DIO test. Our results suggest that RER is mainly affected by the actual state of energy balance; conversely, EE is rather influenced by hunger. Therefore, pharmacological medications that decrease hunger may enhance the efficacy of a hypocaloric diet by maintaining metabolic rate. Furthermore, our results yield the proposal that effects of anorectic drugs on EE and RER should be determined compared to vehicle and pair-fed groups, respectively, in animal models. Copyright © 2015 Elsevier Inc. All rights reserved.

Immunolocalization of an alternative respiratory chain in Antonospora (Paranosema) locustae spores: mitosomes retain their role in microsporidial energy metabolism.

Science.gov (United States)

Dolgikh, Viacheslav V; Senderskiy, Igor V; Pavlova, Olga A; Naumov, Anton M; Beznoussenko, Galina V

2011-04-01

Microsporidia are a group of fungus-related intracellular parasites with severely reduced metabolic machinery. They lack canonical mitochondria, a Krebs cycle, and a respiratory chain but possess genes encoding glycolysis enzymes, a glycerol phosphate shuttle, and ATP/ADP carriers to import host ATP. The recent finding of alternative oxidase genes in two clades suggests that microsporidial mitosomes may retain an alternative respiratory pathway. We expressed the fragments of mitochondrial chaperone Hsp70 (mitHsp70), mitochondrial glycerol-3-phosphate dehydrogenase (mitG3PDH), and alternative oxidase (AOX) from the microsporidium Antonospora (Paranosema) locustae in Escherichia coli. Immunoblotting with antibodies against recombinant polypeptides demonstrated specific accumulation of both metabolic enzymes in A. locustae spores. At the same time comparable amounts of mitochondrial Hsp70 were found in spores and in stages of intracellular development as well. Immunoelectron microscopy of ultrathin cryosections of spores confirmed mitosomal localization of the studied proteins. Small amounts of enzymes of an alternative respiratory chain in merogonial and early sporogonial stages, alongside their accumulation in mature spores, suggest conspicuous changes in components and functions of mitosomes during the life cycle of microsporidia and the important role of these organelles in parasite energy metabolism, at least at the final stages of sporogenesis.

Calorie restriction-like effects of 30 days of resveratrol supplementation on energy metabolism and metabolic profile in obese humans

NARCIS (Netherlands)

Timmers, Silvie; Konings, Ellen; Bilet, Lena; Houtkooper, Riekelt H.; Weijer, van de Tineke; Hoeks, Joris; Krieken, van der Sophie; Ryu, Dongryeol; Kersten, Sander; Moonen-Kornips, Esther; Goossens, Gijs H.; Hesselink, Matthijs K.; Kunz, Iris; Schrauwen-Hinderling, Vera B.; Blaak, Ellen E.; Auwerx, Johan; Schrauwen, Patrick

2011-01-01

Resveratrol is a naturally occurring compound that profoundly affects energy metabolism and mitochondrial function and serves as a calorie restriction mimetic, at least in animal models of obesity. Here we treated 10 healthy, obese men with placebo and 150 mg/day resveratrol in a randomized

Disruption of quercetin metabolism by fungicide affects energy production in honey bees (Apis mellifera).

Science.gov (United States)

Mao, Wenfu; Schuler, Mary A; Berenbaum, May R

2017-03-07

Cytochrome P450 monooxygenases (P450) in the honey bee, Apis mellifera , detoxify phytochemicals in honey and pollen. The flavonol quercetin is found ubiquitously and abundantly in pollen and frequently at lower concentrations in honey. Worker jelly consumed during the first 3 d of larval development typically contains flavonols at very low levels, however. RNA-Seq analysis of gene expression in neonates reared for three days on diets with and without quercetin revealed that, in addition to up-regulating multiple detoxifying P450 genes, quercetin is a negative transcriptional regulator of mitochondrion-related nuclear genes and genes encoding subunits of complexes I, III, IV, and V in the oxidative phosphorylation pathway. Thus, a consequence of inefficient metabolism of this phytochemical may be compromised energy production. Several P450s metabolize quercetin in adult workers. Docking in silico of 121 pesticide contaminants of American hives into the active pocket of CYP9Q1, a broadly substrate-specific P450 with high quercetin-metabolizing activity, identified six triazole fungicides, all fungal P450 inhibitors, that dock in the catalytic site. In adults fed combinations of quercetin and the triazole myclobutanil, the expression of five of six mitochondrion-related nuclear genes was down-regulated. Midgut metabolism assays verified that adult bees consuming quercetin with myclobutanil metabolized less quercetin and produced less thoracic ATP, the energy source for flight muscles. Although fungicides lack acute toxicity, they may influence bee health by interfering with quercetin detoxification, thereby compromising mitochondrial regeneration and ATP production. Thus, agricultural use of triazole fungicides may put bees at risk of being unable to extract sufficient energy from their natural food.

Change in energy metabolism of in vitro produced embryos: an alternative to make them more cryoresistant?

Directory of Open Access Journals (Sweden)

Luzia Renata Oliveira Dias

2017-08-01

Full Text Available For the development of in vitro produced (IVP as well as in vivo produced bovine embryos, it is extremely important that their energy metabolism works properly because the embryo must be able to metabolize energy substrates that are necessary for producing energy. Lipids play an important role in early embryonic development, acting as source of energy for oocytes and embryos. However, it is known that oocytes and embryos, mainly IVP, accumulate large amounts of lipids in the cytoplasm. Although they are extremely important in embryonic development, lipids have been associated with the reduced survival of bovine embryos following cryopreservation. There is evidence that at least four different categories of lipids affect embryo survival after cryopreservation, including triglycerides (TAG, free fatty acids, cholesterol and phospholipids. Thus, many studies are being conducted to improve the resistance of IVP embryos to the cryopreservation process by reducing the concentration or removing the source of serum from the medium or by reducing oocyte/embryo lipids using mechanical or chemical means. Regarding the use of delipidating agents that reduce the uptake and synthesis of fatty acids (FA by cells, substances such as phenazine ethosulfate (PES, forskolin, L-carnitine and isomers of conjugated linoleic acid (CLA have been utilized. This review aims to address important issues related to embryonic energy metabolism, the importance of lipid metabolism and its relation to the cryopreservation of IVP bovine embryos by summarizing the latest research in this field.

Free fatty acid receptors and their role in regulation of energy metabolism.

Science.gov (United States)

Hara, Takafumi; Kimura, Ikuo; Inoue, Daisuke; Ichimura, Atsuhiko; Hirasawa, Akira

2013-01-01

The free fatty acid receptor (FFAR) is a G protein-coupled receptor (GPCR) activated by free fatty acids (FFAs), which play important roles not only as essential nutritional components but also as signaling molecules in numerous physiological processes. In the last decade, FFARs have been identified by the GPCR deorphanization strategy derived from the human genome database. To date, several FFARs have been identified and characterized as critical components in various physiological processes. FFARs are categorized according to the chain length of FFA ligands that activate each FFAR; FFA2 and FFA3 are activated by short chain FFAs, GPR84 is activated by medium-chain FFAs, whereas FFA1 and GPR120 are activated by medium- or long-chain FFAs. FFARs appear to act as physiological sensors for food-derived FFAs and digestion products in the gastrointestinal tract. Moreover, they are considered to be involved in the regulation of energy metabolism mediated by the secretion of insulin and incretin hormones and by the regulation of the sympathetic nerve systems, taste preferences, and inflammatory responses related to insulin resistance. Therefore, because FFARs can be considered to play important roles in physiological processes and various pathophysiological processes, FFARs have been targeted in therapeutic strategies for the treatment of metabolic disorders including type 2 diabetes and metabolic syndrome. In this review, we present a summary of recent progress regarding the understanding of their physiological roles in the regulation of energy metabolism and their potential as therapeutic targets.

Mitochondrial energy metabolism of rat hippocampus after treatment with the antidepressants desipramine and fluoxetine.

Science.gov (United States)

Villa, Roberto Federico; Ferrari, Federica; Bagini, Laura; Gorini, Antonella; Brunello, Nicoletta; Tascedda, Fabio

2017-07-15

Alterations in mitochondrial functions have been hypothesized to participate in the pathogenesis of depression, because brain bioenergetic abnormalities have been detected in depressed patients by neuroimaging in vivo studies. However, this hypothesis is not clearly demonstrated in experimental studies: some suggest that antidepressants are inhibitors of mitochondrial metabolism, while others observe the opposite. In this study, the effects of 21-day treatment with desipramine (15 mg/kg) and fluoxetine (10 mg/kg) were examined on the energy metabolism of rat hippocampus, evaluating the catalytic activity of regulatory enzymes of mitochondrial energy-yielding metabolic pathways. Because of the micro-heterogeneity of brain mitochondria, we have distinguished between (a) non-synaptic mitochondria (FM) of neuronal perikaryon (post-synaptic compartment) and (b) intra-synaptic light (LM) and heavy (HM) mitochondria (pre-synaptic compartment). Desipramine and fluoxetine changed the catalytic activity of specific enzymes in the different types of mitochondria: (a) in FM, both drugs enhanced cytochrome oxidase and glutamate dehydrogenase, (b) in LM, the overall bioenergetics was unaffected and (c) in HM only desipramine increased malate dehydrogenase and decreased the activities of Electron Transport Chain Complexes. These results integrate the pharmacodynamic features of desipramine and fluoxetine at subcellular level, overcoming the previous conflicting data about the effects of antidepressants on brain energy metabolism, mainly referred to whole brain homogenates or to bulk of cerebral mitochondria. With the differentiation in non-synaptic and intra-synaptic mitochondria, this study demonstrates that desipramine and fluoxetine lead to adjustments in the mitochondrial bioenergetics respect to the energy requirements of pre- and post-synaptic compartments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Teaching Energy Metabolism Using Scientific Articles: Implementation of a Virtual Learning Environment for Medical Students

Science.gov (United States)

de Espindola, Marina Bazzo; El-Bacha, Tatiana; Giannella, Tais Rabetti; Struchiner, Miriam; da Silva, Wagner S.; Da Poian, Andrea T.

2010-01-01

This work describes the use of a virtual learning environment (VLE) applied to the biochemistry class for undergraduate, first-year medical students at the Federal University of Rio de Janeiro. The course focused on the integration of energy metabolism, exploring metabolic adaptations in different physiological or pathological states such as…

Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae

Directory of Open Access Journals (Sweden)

WP. Duncan

Full Text Available The metabolic profiles of selected tissues were analyzed in hatchlings of the Amazonian freshwater turtles Podocnemis expansa, P. unifilis and P. sextuberculata. Metabolic design in these species was judged based on the key enzymes of energy metabolism, with special emphasis on carbohydrate, lipid, amino acid and ketone body metabolism. All species showed a high glycolytic potential in all sampled tissues. Based on low levels of hexokinase, glycogen may be an important fuel for these species. The high lactate dehydrogenase activity in the liver may play a significant role in carbohydrate catabolism, possibly during diving. Oxidative metabolism in P. sextuberculata appears to be designed for the use of lipids, amino acids and ketone bodies. The maximal activities of 3-hydroxyacyl-CoA dehydrogenase, malate dehydrogenase, glutamine dehydrogenase, alanine aminotransferase and succinyl-CoA keto transferase display high aerobic potential, especially in muscle and liver tissues of this species. Although amino acids and ketone bodies may be important fuels for oxidative metabolism, carbohydrates and lipids are the major fuels used by P. expansa and P. unifilis. Our results are consistent with the food habits and lifestyle of Amazonian freshwater turtles. The metabolic design, based on enzyme activities, suggests that hatchlings of P. unifilis and P. expansa are predominately herbivorous, whereas P. sextuberculata rely on a mixed diet of animal matter and vegetation.

Analysis of Final Energy Demand by Sector in Malaysia using MAED Model

International Nuclear Information System (INIS)

Kumar, M.; Muhammed Zulfakar Mohd Zolkaffly; Alawiah Musa

2011-01-01

Energy supply security is important in ensuring a long term supply to fulfill the growing energy demand. This paper presents the use of IAEA energy planning tool, Model for Analysis of Energy Demand (MAED) to analyze, simulate and compare final energy demand by five different sectors in Malaysia under some assumptions, bounds and restrictions and the outcome can be used for planning of energy supply in future. (author)

Bone morphogenetic proteins in inflammation, glucose homeostasis and adipose tissue energy metabolism

DEFF Research Database (Denmark)

Grgurevic, Lovorka; Christensen, Gitte Lund; Schulz, Tim J

2016-01-01

implicated in pancreas development as well as control of adult glucose homeostasis. Lastly, we review the recently recognized role of BMPs in brown adipose tissue formation and their consequences for energy expenditure and adiposity. In summary, BMPs play a pivotal role in metabolism beyond their role...... homeostasis (anaemia, hemochromatosis) and oxidative damage. The second and third parts of this review focus on BMPs in the development of metabolic pathologies such as type-2 diabetes mellitus and obesity. The pancreatic beta cells are the sole source of the hormone insulin and BMPs have recently been...

Calorie Restriction-like Effects of 30 Days of Resveratrol Supplementation on Energy Metabolism and Metabolic Profile in Obese Humans

NARCIS (Netherlands)

Timmers, S.; Konings, E.; Bilet, L.; Houtkooper, R.H.; Weijer, van de T.; Goossens, G.H.; Hoeks, J.; Krieken, van der S.; Ryu, D.; Kersten, A.H.; Moonen-Kornips, E.; Hesselink, M.K.C.; Kunz, I.; Schrauwen-Hinderling, V.B.; Blaak, E.E.; Auwerx, J.; Schrauwen, P.

2011-01-01

Resveratrol is a natural compound that affects energy metabolism and mitochondrial function and serves as a calorie restriction mimetic, at least in animal models of obesity. Here, we treated 11 healthy, obese men with placebo and 150 mg/day resveratrol (resVida) in a randomized double-blind

Calorie restriction-like effects of 30 days of resveratrol supplementation on energy metabolism and metabolic profile in obese humans

NARCIS (Netherlands)

Timmers, Silvie; Konings, Ellen; Bilet, Lena; Houtkooper, Riekelt H.; van de Weijer, Tineke; Goossens, Gijs H.; Hoeks, Joris; van der Krieken, Sophie; Ryu, Dongryeol; Kersten, Sander; Moonen-Kornips, Esther; Hesselink, Matthijs K. C.; Kunz, Iris; Schrauwen-Hinderling, Vera B.; Blaak, Ellen E.; Auwerx, Johan; Schrauwen, Patrick

2011-01-01

Resveratrol is a natural compound that affects energy metabolism and mitochondrial function and serves as a calorie restriction mimetic, at least in animal models of obesity. Here, we treated 11 healthy, obese men with placebo and 150 mg/day resveratrol (resVida) in a randomized double-blind

Sex matters: The effects of biological sex on adipose tissue biology and energy metabolism

Directory of Open Access Journals (Sweden)

Teresa G. Valencak

2017-08-01

Full Text Available Adipose tissue is a complex and multi-faceted organ. It responds dynamically to internal and external stimuli, depending on the developmental stage and activity of the organism. The most common functional subunits of adipose tissue, white and brown adipocytes, regulate and respond to endocrine processes, which then determine metabolic rate as well as adipose tissue functions. While the molecular aspects of white and brown adipose biology have become clearer in the recent past, much less is known about sex-specific differences in regulation and deposition of adipose tissue, and the specific role of the so-called pink adipocytes during lactation in females. This review summarises the current understanding of adipose tissue dynamics with a focus on sex-specific differences in adipose tissue energy metabolism and endocrine functions, focussing on mammalian model organisms as well as human-derived data. In females, pink adipocytes trans-differentiate during pregnancy from subcutaneous white adipocytes and are responsible for milk-secretion in mammary glands. Overlooking biological sex variation may ultimately hamper clinical treatments of many aspects of metabolic disorders. Keywords: Body fatness, Adipose tissue, Sex-specific differences, Adipokines, Adipocytes, Obesity, Energy metabolism

Comparison of Various Indices of Energy Metabolism in Recumbent and Healthy Dairy Cows

OpenAIRE

Guyot, Hugues; Detilleux, Johann; Lebreton, Pascal; Garnier, Catherine; Bonvoisin, Marie; Rollin, Frederic; Sandersen, Charlotte

2017-01-01

Background Downer cow syndrome (DCS) is often diagnosed in dairy cattle during the early post-partum period. The etiology of this condition is not completely understood, as it can be related to the energetic or electrolyte metabolism, as well as to infectious diseases or to trauma. Hypothesis/Objectives The aim of this study is to compare energy metabolism and insulin sensitivity indices and various biochemical parameters between recumbent and healthy dairy cows. Animals A prospective study h...

77 FR 44267 - Notice of Availability of the Final Programmatic Environmental Impact Statement for Solar Energy...

Science.gov (United States)

2012-07-27

...] Notice of Availability of the Final Programmatic Environmental Impact Statement for Solar Energy... Environmental Impact Statement for Solar Energy Development in Six Southwestern States (Final Programmatic EIS... RMP Amendments, references, and additional information regarding solar energy development are...

State and location dependence of action potential metabolic cost in cortical pyramidal neurons.

Science.gov (United States)

Hallermann, Stefan; de Kock, Christiaan P J; Stuart, Greg J; Kole, Maarten H P

2012-06-03

Action potential generation and conduction requires large quantities of energy to restore Na(+) and K(+) ion gradients. We investigated the subcellular location and voltage dependence of this metabolic cost in rat neocortical pyramidal neurons. Using Na(+)/K(+) charge overlap as a measure of action potential energy efficiency, we found that action potential initiation in the axon initial segment (AIS) and forward propagation into the axon were energetically inefficient, depending on the resting membrane potential. In contrast, action potential backpropagation into dendrites was efficient. Computer simulations predicted that, although the AIS and nodes of Ranvier had the highest metabolic cost per membrane area, action potential backpropagation into the dendrites and forward propagation into axon collaterals dominated energy consumption in cortical pyramidal neurons. Finally, we found that the high metabolic cost of action potential initiation and propagation down the axon is a trade-off between energy minimization and maximization of the conduction reliability of high-frequency action potentials.

Preliminary case studies of economy and energy profiles for Ireland during 1979-1990. Final report

Energy Technology Data Exchange (ETDEWEB)

Henry, E W

1981-01-01

How Irish 1985 Energy Demand Model (EDM) case study results have been optimized on the supply side, by means of the EFOM model and software, are described. The 1985 case study results are for low, likely, and high cases. The Low case represents a 1985 Irish economic profile for real GNP being 54% greater thand the GNP of 1974. The Likely case relates to 1985 real GNP being 70% greater than that of 1974, and the High to real GNP being 92% greater. The 1985 final energy results emerging from the case studies are tabulated, showing quantities of final energy required by each of the 13 sectors of the Irish EDM. In all three case studies, 5 of the 13 demand sectors take in aggregate more than 76% of the total energy; these five sectors, in decreasing size of demand, are: other household uses; other industries; private transport; cement; other services. The preparation for EFOM is described. The optimal final energy flows, with some comparisons with the non-optimal inital flows, are considered. The gross primary energy quantity and cost underlying the optimal final energy flows are examined in detail.

Bio-Energy during Finals: Stress Reduction for a University Community.

Science.gov (United States)

Running, Alice; Hildreth, Laura

2016-01-01

To re-examine the effectiveness of a bio-energy intervention on self-reported stress for a convenience sample of university students during dead week, a quasi-experimental, single-group pretest-posttest design was used. Thirty-three students participated, serving as their own controls. After participants had consented, a 15-min Healing Touch intervention followed enrollment. Self-reported stress was significantly reduced after the bio-energy (Healing Touch) intervention. Bio-energy therapy has shown to be beneficial in reducing stress for students during dead week, the week before final examinations. Further research is needed.

Energy efficiency of computer power supply units - Final report

Energy Technology Data Exchange (ETDEWEB)

Aebischer, B. [cepe - Centre for Energy Policy and Economics, Swiss Federal Institute of Technology Zuerich, Zuerich (Switzerland); Huser, H. [Encontrol GmbH, Niederrohrdorf (Switzerland)

2002-11-15

This final report for the Swiss Federal Office of Energy (SFOE) takes a look at the efficiency of computer power supply units, which decreases rapidly during average computer use. The background and the purpose of the project are examined. The power supplies for personal computers are discussed and the testing arrangement used is described. Efficiency, power-factor and operating points of the units are examined. Potentials for improvement and measures to be taken are discussed. Also, action to be taken by those involved in the design and operation of such power units is proposed. Finally, recommendations for further work are made.

Visceral metabolism and efficiency of energy use by ruminants

Directory of Open Access Journals (Sweden)

Kozloski Gilberto Vilmar

2001-01-01

Full Text Available The visceral system (liver and portal-drained viscera represents an interface between diet and the animal, and it acts as the main site of regulation of nutrients that are used for maintenance, growth, lactation, reproduction, and physical activities of animals. However the functions carried out by visceral organs have, however, a significant energetic cost and are influenced by a variety of factors, such as the level of feed intake and diet composition, among others. As a result, variable quantities of substances are metabolized by them and, thus, the pattern and the quantity of nutrients available to the peripheral tissues can be quite different from those absorbed at the intestinal lumen. Probably, the major source of variation in the efficiency of utilization of metabolizable energy among feeds is associated mainly with visceral metabolism and it is unlikely that the ratio ketogenic/glucogenic of absorbed substances has determinant effect under physiological conditions.

E2 = Energy concept x final storage [+ the law?

International Nuclear Information System (INIS)

Schneider, Horst

2010-01-01

The world is changing all the time, opinions and evaluations assume new shapes. It is the function of the law to ensure reliability and confidence by its very continuity. However, it is not only the revisions of the law which are subject to the zeitgeist; also the interpretations and applications of the law are not exempt from current trends of thought. The coalition agreement signed by the CDU/CSU and FDP parties on October 26, 2009 announced an energy concept encompassing life extension of nuclear power plants and a continued exploration of the Gorleben salt dome as a repository for high-level waste producting heat. The Deutsche Umwelthilfe (DUH) tries to prove in a legal opinion that an extension of nuclear power plant life was illegal and unconstitutional because the problem of the back end of the fuel cycle was not likely to be solved in a foreseeable time. Continuing exploration of the Gorleben salt dome is based on mining law. The agency responsible for filing an application under the German Atomic Energy Act is the Federal Office for Radiation Protection (BfS). In Germany, the final storage issue has always been an area of violent political debate. Given the strategic purpose of the DUH legal opinion as a tool furthering opt-out of the use of nuclear power, several points are presented and discussed in this article which were overlooked in that opinion. The equation, 'energy concept x final storage =..?', seems to be open today. The law can support results. Existing legal regulations especially about the nuclear power sector must be used as starting points for new ideas: The existence of legal norms is to ensure reliability and confidence. Consequently, changes in the law must be prepared very thoroughly and weighed comprehensively. In current thinking, after all, transparency is part of political action, especially so in defining and implementing goals in topics such as the energy concept and final storage. Yet, unnecessary delays would not be justified

Metabolic substrate use and the turnover of endogenous energy reserves in broad-tailed hummingbirds (Selasphorus platycercus).

Science.gov (United States)

Carleton, Scott A; Bakken, Bradley Hartman; Del Rio, Carlos Martínez

2006-07-01

We fed broad-tailed hummingbirds (Selasphorus platycercus) diets of contrasting carbon isotope composition and measured changes in the delta(13)C of expired breath through time. By measuring the delta(13)C in the breath of fed and fasted birds we were able to quantify the fraction of metabolism fueled by assimilated sugars and endogenous energy reserves. These measurements also allowed us to estimate the fractional turnover of carbon in the hummingbirds' energy reserves. When hummingbirds were feeding, they fueled their metabolism largely ( approximately 90%) with assimilated sugars. The rate of carbon isotope incorporation into the energy reserves of hummingbirds was higher when birds were gaining as opposed to losing body mass. The average residence time of a carbon atom in the hummingbirds' energy reserves ranged from 1 to 2 days.

Aspects of Energy Metabolism in Mangalitsa Pigs Exposed at Thermic Neutral Temperature

Directory of Open Access Journals (Sweden)

Monica Pârvu

2011-10-01

Full Text Available The studies aimed the energy metabolism determination in Mangalitsa pigs exposed at thermic neutral temperature, compared to Large White pigs. The experimental period was between 80 and 100 kg liveweight. The animals had free access to standard, isoprotein and isocalory diets, with 13.5% crude protein (CP and 3100 kcal/kg metabolizable energy. Feed intake was measured on a daily basis. The energy-protein balance was calculated on the basis of comparative slaughter made at the beginning and end of the experiment. The metabolizable energy (MEc was estimated by chemical analysis (feed and excreta using mathematical modelling and the Whittemore’s formula. The metabolizable energy utilization efficiency was 0.61 at Large White and 0.53 at Mangalitsa.

Microalgal bioengineering for sustainable energy development: Recent transgenesis and metabolic engineering strategies.

Science.gov (United States)

Banerjee, Chiranjib; Singh, Puneet Kumar; Shukla, Pratyoosh

2016-03-01

Exploring the efficiency of algae to produce remarkable products can be directly benefitted by studying its mechanism at systems level. Recent advents in biotechnology like flux balance analysis (FBA), genomics and in silico proteomics minimize the wet lab exertion. It is understood that FBA predicts the metabolic products, metabolic pathways and alternative pathway to maximize the desired product, and these are key components for microalgae bio-engineering. This review encompasses recent transgenesis techniques and metabolic engineering strategies applied to different microalgae for improving different traits. Further it also throws light on RNAi and riboswitch engineering based methods which may be advantageous for high throughput microalgal research. A valid and optimally designed microalga can be developed where every engineering strategies meet each other successfully and will definitely fulfill the market needs. It is also to be noted that Omics (viz. genetic and metabolic manipulation with bioinformatics) should be integrated to develop a strain which could prove to be a futuristic solution for sustainable development for energy. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Adipose energy stores, physical work, and the metabolic syndrome: lessons from hummingbirds.

Science.gov (United States)

Hargrove, James L

2005-12-13

Hummingbirds and other nectar-feeding, migratory birds possess unusual adaptive traits that offer important lessons concerning obesity, diabetes and the metabolic syndrome. Hummingbirds consume a high sugar diet and have fasting glucose levels that would be severely hyperglycemic in humans, yet these nectar-fed birds recover most glucose that is filtered into the urine. Hummingbirds accumulate over 40% body fat shortly before migrations in the spring and autumn. Despite hyperglycemia and seasonally elevated body fat, the birds are not known to become diabetic in the sense of developing polyuria (glucosuria), polydipsia and polyphagia. The tiny (3-4 g) Ruby-throated hummingbird has among the highest mass-specific metabolic rates known, and loses most of its stored fat in 20 h by flying up to 600 miles across the Gulf of Mexico. During the breeding season, it becomes lean and maintains an extremely accurate energy balance. In addition, hummingbirds can quickly enter torpor and reduce resting metabolic rates by 10-fold. Thus, hummingbirds are wonderful examples of the adaptive nature of fat tissue, and may offer lessons concerning prevention of metabolic syndrome in humans.

Glutamate dehydrogenase is essential to sustain neuronal oxidative energy metabolism during stimulation

DEFF Research Database (Denmark)

Hohnholt, Michaela C; Andersen, Vibe H; Andersen, Jens V

2017-01-01

by glutamate was significantly lower in brain mitochondria from GDH KO mice and synaptosomes were not able to increase their respiration upon an elevated energy demand. The role of GDH for metabolism of glutamine and the respiratory capacity underscore the importance of GDH for neurons particularly during...

Cerebral ketone body metabolism.

Science.gov (United States)

Morris, A A M

2005-01-01

Ketone bodies (KBs) are an important source of energy for the brain. During the neonatal period, they are also precursors for the synthesis of lipids (especially cholesterol) and amino acids. The rate of cerebral KB metabolism depends primarily on the concentration in blood; high concentrations occur during fasting and on a high-fat diet. Cerebral KB metabolism is also regulated by the permeability of the blood-brain barrier (BBB), which depends on the abundance of monocarboxylic acid transporters (MCT1). The BBB's permeability to KBs increases with fasting in humans. In rats, permeability increases during the suckling period, but human neonates have not been studied. Monocarboxylic acid transporters are also present in the plasma membranes of neurons and glia but their role in regulating KB metabolism is uncertain. Finally, the rate of cerebral KB metabolism depends on the activities of the relevant enzymes in brain. The activities vary with age in rats, but reliable results are not available for humans. Cerebral KB metabolism in humans differs from that in the rat in several respects. During fasting, for example, KBs supply more of the brain's energy in humans than in the rat. Conversely, KBs are probably used more extensively in the brain of suckling rats than in human neonates. These differences complicate the interpretation of rodent studies. Most patients with inborn errors of ketogenesis develop normally, suggesting that the only essential role for KBs is as an alternative fuel during illness or prolonged fasting. On the other hand, in HMG-CoA lyase deficiency, imaging generally shows asymptomatic white-matter abnormalities. The ability of KBs to act as an alternative fuel explains the effectiveness of the ketogenic diet in GLUT1 deficiency, but its effectiveness in epilepsy remains unexplained.

A potential mechanism of energy-metabolism oscillation in an aerobic chemostat culture of the yeast Saccharomyces cerevisiae.

Science.gov (United States)

Xu, Zhaojun; Tsurugi, Kunio

2006-04-01

The energy-metabolism oscillation in aerobic chemostat cultures of yeast is a periodic change of the respiro-fermentative and respiratory phase. In the respiro-fermentative phase, the NADH level was kept high and respiration was suppressed, and glucose was anabolized into trehalose and glycogen at a rate comparable to that of catabolism. On the transition to the respiratory phase, cAMP levels increased triggering the breakdown of storage carbohydrates and the increased influx of glucose into the glycolytic pathway activated production of glycerol and ethanol consuming NADH. The resulting increase in the NAD(+)/NADH ratio stimulated respiration in combination with a decrease in the level of ATP, which was consumed mainly in the formation of biomass accompanying budding, and the accumulated ethanol and glycerol were gradually degraded by respiration via NAD(+)-dependent oxidation to acetate and the respiratory phase ceased after the recovery of NADH and ATP levels. However, the mRNA levels of both synthetic and degradative enzymes of storage carbohydrates were increased around the early respiro-fermentative phase, when storage carbohydrates are being synthesized, suggesting that the synthetic enzymes were expressed directly as active forms while the degradative enzymes were activated late by cAMP. In summary, the energy-metabolism oscillation is basically regulated by a feedback loop of oxido-reductive reactions of energy metabolism mediated by metabolites like NADH and ATP, and is modulated by metabolism of storage carbohydrates in combination of post-translational and transcriptional regulation of the related enzymes. A potential mechanism of energy-metabolism oscillation is proposed.

Exercising for Life? Energy Metabolism, Body Composition, and Longevity in Mice Exercising at Different Intensities

NARCIS (Netherlands)

Vaanholt, Lobke M.; Daan, Serge; Garland, Theodore; Visser, G. Henk; Garland Jr., Theodore

2010-01-01

Studies that have found a positive influence of moderate, non-exhaustive exercise on life expectancy contradict the rate-of-living theory, which predicts that high energy expenditure in exercising animals should shorten life. We investigated effects of exercise on energy metabolism and life span in

Formate as an energy source for microbial metabolism in chemosynthetic zones of hydrothermal ecosystems.

Science.gov (United States)

Windman, Todd; Zolotova, Natalya; Schwandner, Florian; Shock, Everett L

2007-12-01

Formate, a simple organic acid known to support chemotrophic hyperthermophiles, is found in hot springs of varying temperature and pH. However, it is not yet known how metabolic strategies that use formate could contribute to primary productivity in hydrothermal ecosystems. In an effort to provide a quantitative framework for assessing the role of formate metabolism, concentration data for dissolved formate and many other solutes in samples from Yellowstone hot springs were used, together with data for coexisting gas compositions, to evaluate the overall Gibbs energy for many reactions involving formate oxidation or reduction. The result is the first rigorous thermodynamic assessment of reactions involving formate oxidation to bicarbonate and reduction to methane coupled with various forms of iron, nitrogen, sulfur, hydrogen, and oxygen for hydrothermal ecosystems. We conclude that there are a limited number of reactions that can yield energy through formate reduction, in contrast to numerous formate oxidation reactions that can yield abundant energy for chemosynthetic microorganisms. Because the energy yields are so high, these results challenge the notion that hydrogen is the primary energy source of chemosynthetic microbes in hydrothermal ecosystems.

Molecular Interaction of Bone Marrow Adipose Tissue with Energy Metabolism.

Science.gov (United States)

Suchacki, Karla J; Cawthorn, William P

2018-01-01

The last decade has seen a resurgence in the study of bone marrow adipose tissue (BMAT) across diverse fields such as metabolism, haematopoiesis, skeletal biology and cancer. Herein, we review the most recent developments of BMAT research in both humans and rodents, including the distinct nature of BMAT; the autocrine, paracrine and endocrine interactions between BMAT and various tissues, both in physiological and pathological scenarios; how these interactions might impact energy metabolism; and the most recent technological advances to quantify BMAT. Though still dwarfed by research into white and brown adipose tissues, BMAT is now recognised as endocrine organ and is attracting increasing attention from biomedical researchers around the globe. We are beginning to learn the importance of BMAT both within and beyond the bone, allowing us to better appreciate the role of BMAT in normal physiology and disease.

Energy Metabolism and Inflammation in Brain Aging and Alzheimer’s Disease

Science.gov (United States)

Yin, Fei; Sancheti, Harsh; Patil, Ishan; Cadenas, Enrique

2016-01-01

The high energy demand of the brain renders it sensitive to changes in energy fuel supply and mitochondrial function. Deficits in glucose availability and mitochondrial function are well-known hallmarks of brain aging and are particularly accentuated in neurodegenerative disorders such as Alzheimer’s disease. As important cellular sources of H2O2, mitochondrial dysfunction is usually associated with altered redox status. Bioenergetic deficits and chronic oxidative stress are both major contributors to cognitive decline associated with brain aging and Alzheimer’s disease. Neuroinflammatory changes, including microglial activation and production of inflammatory cytokines, are observed in neurodegenerative diseases and normal aging. The bioenergetic hypothesis advocates for sequential events from metabolic deficits to propagation of neuronal dysfunction, to aging, and to neurodegeneration, while the inflammatory hypothesis supports microglia activation as the driving force for neuroinflammation. Nevertheless, growing evidence suggests that these diverse mechanisms have redox dysregulation as a common denominator and connector. An independent view of the mechanisms underlying brain aging and neurodegeneration is being replaced by one that entails multiple mechanisms coordinating and interacting with each other. This review focuses on the alterations in energy metabolism and inflammatory responses and their connection via redox regulation in normal brain aging and Alzheimer’s disease. Interactions of these systems is reviewed based on basic research and clinical studies. PMID:27154981

NAD+ metabolism and the control of energy homeostasis - a balancing act between mitochondria and the nucleus

Science.gov (United States)

Cantó, Carles; Menzies, Keir; Auwerx, Johan

2015-01-01

NAD+ has emerged as a vital cofactor that can rewire metabolism, activate sirtuins and maintain mitochondrial fitness through mechanisms such as the mitochondrial unfolded protein response. This improved understanding of NAD+ metabolism revived interest in NAD+ boosting strategies to manage a wide spectrum of diseases, ranging from diabetes to cancer. In this review, we summarize how NAD+ metabolism links energy status with adaptive cellular and organismal responses and how this knowledge can be therapeutically exploited. PMID:26118927

Brazilian energy balance 2015: year 2014 - final report

International Nuclear Information System (INIS)

2015-01-01

The Balance (BEB) contains the accounting relative to energy supply and consumption, as well the conversion processes and foreign trade. It presents in a single document the historical series of these operations and information about reserves, installed capacities and Federal States data. The BEB is divided into eight chapters and ten annexes, whose contents are as follow. Chapters' content can be described as follows: Chapter 1 - Energy Analysis and Aggregated Data - presents energy highlights per source in 2014 and analyses the evolution of the domestic energy supply and its relationship with economic growth. Chapter 2 - Energy Supply and Demand by Source - has the accountancy, per primary and secondary energy sources, of the production, import, export, variation of stocks, losses, adjustments, disaggregated total per socioeconomic sector in the country. Chapter 3 - Energy Consumption by Sector - presents the final energy consumption classified by primary and secondary source for each sector of the economy. Chapter 4 - Energy Imports and Exports - presents the evolution of the data on the import and export of energy and the dependence on external energy. Chapter 5 - Balance of Transformation Centers - presents the energy balances for the energy transformation centers including their losses. Chapter 6 - Energy Resources and Reserves - has the basic concepts use in the survey of resources and reserves of primary energy sources. Chapter 7 - Energy and Socio economics - contains a comparison of energy, economic and population parameters, specific consumption, energy intensities, average prices and spending on petroleum imports. Chapter 8 - State Energy Data - presents energy data for the states by Federal Unit, main energy source production, energy installations, reserves and hydraulic potential. Relating to annexes the current structure is presented bellow: Annex I - Installed Capacity - shows the installed capacity of electricity generation, the installed

Effects of Dietary Protein Source and Quantity during Weight Loss on Appetite, Energy Expenditure, and Cardio-Metabolic Responses

Directory of Open Access Journals (Sweden)

Jia Li

2016-01-01

Full Text Available Higher protein meals increase satiety and the thermic effect of feeding (TEF in acute settings, but it is unclear whether these effects remain after a person becomes acclimated to energy restriction or a given protein intake. This study assessed the effects of predominant protein source (omnivorous, beef/pork vs. lacto-ovo vegetarian, soy/legume and quantity (10%, 20%, or 30% of energy from protein on appetite, energy expenditure, and cardio-metabolic indices during energy restriction (ER in overweight and obese adults. Subjects were randomly assigned to one protein source and then consumed diets with different quantities of protein (4 weeks each in a randomized crossover manner. Perceived appetite ratings (free-living and in-lab, TEF, and fasting cardio-metabolic indices were assessed at the end of each 4-week period. Protein source and quantity did not affect TEF, hunger, or desire to eat, other than a modestly higher daily composite fullness rating with 30% vs. 10% protein diet (p = 0.03. While the 20% and 30% protein diets reduced cholesterol, triacylglycerol, and APO-B vs. 10% protein (p < 0.05, protein source did not affect cardio-metabolic indices. In conclusion, diets varying in protein quantity with either beef/pork or soy/legume as the predominant source have minimal effects on appetite control, energy expenditure and cardio-metabolic risk factors during ER-induced weight loss.

Simulating the physiology of athletes during endurance sports events: modelling human energy conversion and metabolism

NARCIS (Netherlands)

van Beek, J.H.G.M.; Supandi, F.B.; Gavai, Anand; de Graaf, A.A.; Binsl, T.W.; Hettling, H.

2011-01-01

The human physiological system is stressed to its limits during endurance sports competition events.We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We

Simulating the physiology of athletes during endurance sports events: Modelling human energy conversion and metabolism

NARCIS (Netherlands)

Beek, J.H.G.M. van; Supandi, F.; Gavai, A.K.; Graaf, A.A. de; Binsl, T.W.; Hettling, H.

2011-01-01

The human physiological system is stressed to its limits during endurance sports competition events.We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We

Forecasting of the incorporated energy in the final demand of the brazilian economy in 2005

International Nuclear Information System (INIS)

Cunha, Marcelo Pereira da; Pereira, Jose Tomaz Vieira

2008-01-01

This work presents the application of a methodology for evaluation of the primary energy incorporated by the productive sectors of a economy at the final demand - using of a income-product mode. A methodology is applied in the evaluation of the energy incorporated to 25 sectors of the brazilian economy, by using the the data available in the national counts (IBGE - 2007), and the National Energy Balance for the year 2005 (EPE - 2007). For each sector, the results are presented in terms of the primary energy incorporated (in petroleum equivalent tons per R$ 1,000), of the participation of renewable energy, and the total primary energy distribution for the offered products by the 25 sectors to be consumption by the final demand. Among some interesting results in terms of final demand, it is highlighted the presence of 96.5% of renewable primary energy for the sector of alcohol, and 5.3% for the sector of petroleum refining products sector. In terms of the total energy distribution,the petroleum refining and coke sector were the most significant contribution to the incorporation of primary energy, presenting 16.1% of the total ahead of foods and beverages which presents 12.1%. Related to the final demand components, families consumption was responsible by the 57.7% of the total, the exports with 25.3%, the gross capital formation (investments and stock variations) with 11.3%, and the govern consumption wit 5.7%

A Transcript-Specific eIF3 Complex Mediates Global Translational Control of Energy Metabolism

Directory of Open Access Journals (Sweden)

Meera Shah

2016-08-01

Full Text Available The multi-subunit eukaryotic translation initiation factor eIF3 is thought to assist in the recruitment of ribosomes to mRNA. The expression of eIF3 subunits is frequently disrupted in human cancers, but the specific roles of individual subunits in mRNA translation and cancer remain elusive. Using global transcriptomic, proteomic, and metabolomic profiling, we found a striking failure of Schizosaccharomyces pombe cells lacking eIF3e and eIF3d to synthesize components of the mitochondrial electron transport chain, leading to a defect in respiration, endogenous oxidative stress, and premature aging. Energy balance was maintained, however, by a switch to glycolysis with increased glucose uptake, upregulation of glycolytic enzymes, and strict dependence on a fermentable carbon source. This metabolic regulatory function appears to be conserved in human cells where eIF3e binds metabolic mRNAs and promotes their translation. Thus, via its eIF3d-eIF3e module, eIF3 orchestrates an mRNA-specific translational mechanism controlling energy metabolism that may be disrupted in cancer.

The metabolic power and energetic demands of elite Gaelic football match play.

Science.gov (United States)

Malone, Shane; Solan, Barry; Collins, Kieran; Doran, Dominic

2017-05-01

Metabolic power has not yet been investigated within elite Gaelic football. The aim of the current investigation was to compare the metabolic power demands between positional groups and examine the temporal profile of elite Gaelic football match play. Global positional satellite system (GPS) data were collected from 50 elite Gaelic football players from 4 inter-county teams during 35 elite competitive matches over a three season period. A total of 351 complete match samples were obtained for final analysis. Players were categorized based on positional groups; full-back, half-back, midfield, half-forward and full-forward. Instantaneous raw velocity data was obtained from the GPS and exported to a customized spreadsheet which provided estimations of both speed based, derived metabolic power and energy expenditure variables (total distance, high speed distance, average metabolic power, high power distance and total energy expenditure). Match mean distance was 9222±1588 m, reflective of an average metabolic power of 9.5-12.5 W·kg-1, with an average energy expenditure of 58-70 Kj·kg-1 depending on position. There were significant differences between positional groups for both speed-based and metabolic power indices. Midfielders covered more total and high-speed distance, as well as greater average and overall energy expenditure compared to other positions (Ppower distance, as well as average metabolic power throughout the match (Ppower and traditional running based variables. The middle three positions (midfield, half-back and half-forward) possess greater activity profiles when compared to other positional groups. The reduction in metabolic power and traditional running based variables are comparable across match play. The current study demonstrates that metabolic power may contribute to our understanding of Gaelic football match-play.

PET studies of brain energy metabolism in a model of subcortical dementia: progressive supranuclear Palsy

International Nuclear Information System (INIS)

Blin, J.; Baron, J.C.; Cambon, H.

1988-01-01

In 41 patients with clinically determined Progressive Supranuclear Palsy, a model of degenerative subcortical dementia, alterations in regional brain energy metabolism with respect to control subjects have been investigated using positron computed tomography and correlated to clinical and neuropsychological scores. A generalized significant reduction in brain metabolism was found, which predominated in the prefrontal cortex in accordance with, and statistically correlated to, the frontal neuropsychological score

Root Transcriptomic Analysis Revealing the Importance of Energy Metabolism to the Development of Deep Roots in Rice (Oryza sativa L.

Directory of Open Access Journals (Sweden)

Qiaojun Lou

2017-07-01

Full Text Available Drought is the most serious abiotic stress limiting rice production, and deep root is the key contributor to drought avoidance. However, the genetic mechanism regulating the development of deep roots is largely unknown. In this study, the transcriptomes of 74 root samples from 37 rice varieties, representing the extreme genotypes of shallow or deep rooting, were surveyed by RNA-seq. The 13,242 differentially expressed genes (DEGs between deep rooting and shallow rooting varieties (H vs. L were enriched in the pathway of genetic information processing and metabolism, while the 1,052 DEGs between the deep roots and shallow roots from each of the plants (D vs. S were significantly enriched in metabolic pathways especially energy metabolism. Ten quantitative trait transcripts (QTTs were identified and some were involved in energy metabolism. Forty-nine candidate DEGs were confirmed by qRT-PCR and microarray. Through weighted gene co-expression network analysis (WGCNA, we found 18 hub genes. Surprisingly, all these hub genes expressed higher in deep roots than in shallow roots, furthermore half of them functioned in energy metabolism. We also estimated that the ATP production in the deep roots was faster than shallow roots. Our results provided a lot of reliable candidate genes to improve deep rooting, and firstly highlight the importance of energy metabolism to the development of deep roots.

Root Transcriptomic Analysis Revealing the Importance of Energy Metabolism to the Development of Deep Roots in Rice (Oryza sativa L.).

Science.gov (United States)

Lou, Qiaojun; Chen, Liang; Mei, Hanwei; Xu, Kai; Wei, Haibin; Feng, Fangjun; Li, Tiemei; Pang, Xiaomeng; Shi, Caiping; Luo, Lijun; Zhong, Yang

2017-01-01

Drought is the most serious abiotic stress limiting rice production, and deep root is the key contributor to drought avoidance. However, the genetic mechanism regulating the development of deep roots is largely unknown. In this study, the transcriptomes of 74 root samples from 37 rice varieties, representing the extreme genotypes of shallow or deep rooting, were surveyed by RNA-seq. The 13,242 differentially expressed genes (DEGs) between deep rooting and shallow rooting varieties (H vs. L) were enriched in the pathway of genetic information processing and metabolism, while the 1,052 DEGs between the deep roots and shallow roots from each of the plants (D vs. S) were significantly enriched in metabolic pathways especially energy metabolism. Ten quantitative trait transcripts (QTTs) were identified and some were involved in energy metabolism. Forty-nine candidate DEGs were confirmed by qRT-PCR and microarray. Through weighted gene co-expression network analysis (WGCNA), we found 18 hub genes. Surprisingly, all these hub genes expressed higher in deep roots than in shallow roots, furthermore half of them functioned in energy metabolism. We also estimated that the ATP production in the deep roots was faster than shallow roots. Our results provided a lot of reliable candidate genes to improve deep rooting, and firstly highlight the importance of energy metabolism to the development of deep roots.

[Coactivators in energy metabolism: peroxisome proliferator-activated receptor-gamma coactivator 1 family].

Science.gov (United States)

Wang, Rui; Chang, Yong-sheng; Fang, Fu-de

2009-12-01

Peroxisome proliferator-activated receptor gamma coactivator 1 (PGC1) family is highly expressed in tissues with high energy metabolism. They coactivate transcription factors in regulating genes engaged in processes such as gluconeogenesis, adipose beta-oxydation, lipoprotein synthesis and secretion, mitochondrial biogenesis, and oxidative metabolism. Protein conformation studies demonstrated that they lack DNA binding domains and act as coactivators through physical interaction with transcription factors. PGC1 activity is regulated at transcription level or by multiple covalent chemical modifications such as phosphorylation, methylation and acetylation/deacetylation. Abnormal expression of PGC1 coactivators usually is closely correlated with diseases such as diabetes, obesity, hyperglycemia, hyperlipemia, and arterial and brain neuron necrosis diseases.

GH and IGF1: Roles in Energy Metabolism of Long-Living GH Mutant Mice

OpenAIRE

Brown-Borg, Holly M.; Bartke, Andrzej

2012-01-01

Of the multiple theories to explain exceptional longevity, the most robust of these has centered on the reduction of three anabolic protein hormones, growth hormone (GH), insulin-like growth factor, and insulin. GH mutant mice live 50% longer and exhibit significant differences in several aspects of energy metabolism as compared with wild-type mice. Mitochondrial metabolism is upregulated in the absence of GH, whereas in GH transgenic mice and dwarf mice treated with GH, multiple aspects of t...

Energy conservation in selected buildings, Gdansk. 1. final report

International Nuclear Information System (INIS)

1997-02-01

This Final Report marks the end of the implementation stage of the project: 'Energy Conservation in Selected Buildings in Gdansk, Poland' supported by the Danish Environment-related Energy Sector Programme for Poland under the Danish Energy Agency. The residential and commercial sectors together with public buildings account for 40-45% of the total energy consumption and are dominated by the use of space heating and hot water. The sector has a significant over-consumption of energy, which first of all is due to the lack of or too weak incentives for the individual tenants to decrease the energy consumption. Bad thermal insulation of buildings and inefficient central heating systems with a widespread lack of measurement and automatic control systems give cause for extensive heat losses. The objective of the project has been to document the effects of energy savings in 18 multi-family houses when different types of energy saving measures are applied. These measures include thermal insulation of buildings, refurbishment of the heating system and introduction of individual billing system for heating and hot tap water. Energy audits of 18 buildings were performed by combination of on-site inspection of all buildings and data collection from the available drawings, technical descriptions, etc. The on-site inspection was carried out by use of an energy audit scheme specially developed for this project. (EG)

Energy conservation in selected buildings, Gdansk. 1. final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-02-01

This Final Report marks the end of the implementation stage of the project: `Energy Conservation in Selected Buildings in Gdansk, Poland` supported by the Danish Environment-related Energy Sector Programme for Poland under the Danish Energy Agency. The residential and commercial sectors together with public buildings account for 40-45% of the total energy consumption and are dominated by the use of space heating and hot water. The sector has a significant over-consumption of energy, which first of all is due to the lack of or too weak incentives for the individual tenants to decrease the energy consumption. Bad thermal insulation of buildings and inefficient central heating systems with a widespread lack of measurement and automatic control systems give cause for extensive heat losses. The objective of the project has been to document the effects of energy savings in 18 multi-family houses when different types of energy saving measures are applied. These measures include thermal insulation of buildings, refurbishment of the heating system and introduction of individual billing system for heating and hot tap water. Energy audits of 18 buildings were performed by combination of on-site inspection of all buildings and data collection from the available drawings, technical descriptions, etc. The on-site inspection was carried out by use of an energy audit scheme specially developed for this project. (EG)

The effects of home oxygen therapy on energy metabolism in patients with COPD

Science.gov (United States)

Kırıcı Berber, Nurcan; Yetkin, Özkan; Kılıç, Talat; Berber, Ilhami; Özgel, Mehmet

2018-01-01

Background COPD is preventable and treatable and is characterized by completely nonreversible airflow obstruction. In this study, we aimed to investigate the effect of long-term oxygen therapy on patients with stage 4 COPD who were followed up and treated at the polyclinic or clinic service. We evaluated the effects of oxygen therapy on energy metabolism and physical activity in patients with COPD. Methods Nineteen patients with COPD (16 male/3 female), treated with oxygen therapy for the first time, were included in this study. Analysis of arterial blood gases and pulmonary function test was performed. Metabolic Holter device (SenseWear® Armband) was placed pre- and post-oxygen therapy on the patients’ arm for at least 3 days. This device captures Holter data in a digitized electronic system, and the daily average value was calculated from the data. Results Post-oxygen treatment showed a significant increase in energy expenditure by patients with COPD (pretreatment, 1,497±596 joule; posttreatment, 2,977±5,985 joule; P=0.044). Moreover, number of steps during walking (pretreatment, 2,056±256; posttreatment, 2,120±195; P=0.03), resting (pretreatment, 6.36±3.31 hours; posttreatment, 3.47±2.19 hours; P<0.03), and sleeping (pretreatment, 4.23±2.13 hours; posttreatment, 2.33±1.42 hours; P<0.00) showed significant differences. Increased daily energy expenditure in patients with respiratory failure was detected with long-term oxygen therapy. In addition, the immobility of patients decreased and duration of physical activity increased in patients with COPD. Conclusion In this study, positive effects of long-term oxygen therapy have been demonstrated with respect to energy metabolism and physical activity of patients with COPD. Thus, we recommend that medication adherence and long-term oxygen therapy should begin early in patients with COPD.

The metabolic ER stress sensor IRE1α suppresses alternative activation of macrophages and impairs energy expenditure in obesity.

Science.gov (United States)

Shan, Bo; Wang, Xiaoxia; Wu, Ying; Xu, Chi; Xia, Zhixiong; Dai, Jianli; Shao, Mengle; Zhao, Feng; He, Shengqi; Yang, Liu; Zhang, Mingliang; Nan, Fajun; Li, Jia; Liu, Jianmiao; Liu, Jianfeng; Jia, Weiping; Qiu, Yifu; Song, Baoliang; Han, Jing-Dong J; Rui, Liangyou; Duan, Sheng-Zhong; Liu, Yong

2017-05-01

Obesity is associated with metabolic inflammation and endoplasmic reticulum (ER) stress, both of which promote metabolic disease progression. Adipose tissue macrophages (ATMs) are key players orchestrating metabolic inflammation, and ER stress enhances macrophage activation. However, whether ER stress pathways underlie ATM regulation of energy homeostasis remains unclear. Here, we identified inositol-requiring enzyme 1α (IRE1α) as a critical switch governing M1-M2 macrophage polarization and energy balance. Myeloid-specific IRE1α abrogation in Ern1 f/f ; Lyz2-Cre mice largely reversed high-fat diet (HFD)-induced M1-M2 imbalance in white adipose tissue (WAT) and blocked HFD-induced obesity, insulin resistance, hyperlipidemia and hepatic steatosis. Brown adipose tissue (BAT) activity, WAT browning and energy expenditure were significantly higher in Ern1 f/f ; Lyz2-Cre mice. Furthermore, IRE1α ablation augmented M2 polarization of macrophages in a cell-autonomous manner. Thus, IRE1α senses protein unfolding and metabolic and immunological states, and consequently guides ATM polarization. The macrophage IRE1α pathway drives obesity and metabolic syndrome through impairing BAT activity and WAT browning.

Effect of melatonin and lighting schedule on energy metabolism in broiler chickens

NARCIS (Netherlands)

Apeldoorn, E.J.; Schrama, J.W.; Mashaly, M.M.; Parmentier, H.K.

1999-01-01

The effect of melatonin and lighting schedule on energy metabolism in broiler chickens was studied. Eight groups of six female broiler chickens each were assigned to a continuous lighting schedule [23 h light (L):1 h darkness (D)] or an intermittent lighting schedule (1L:3D), and were fed a diet

Experience in the modular teaching of the integrated course of metabolism and energy

Institute of Scientific and Technical Information of China (English)

Jian HUANG; Qian LI; Xue-mei TONG; Rong YANG; Ping ZHANG

2015-01-01

The teaching of eight-year clinical medicine program of Shanghai Jiao Tong University School of Medicine was reformed since 2009 to replace the traditional teaching model with modular teaching. As one of reformed courses,the metabolism and energy course combines biochemistry and physiology related knowledge points and endeavors to overcome shortcomings of traditional basic medical knowledge education,such as simple learning contents,isolation between basic medicine and clinical medicine,simple teaching methods of teachers,and passive learning methods of students. After 6 years of teaching practice,the new teaching model has been recognized by both teachers and students and the teaching quality improves comprehensively,but there are still some shortcomings that need to be overcome. This paper summarizes the gain and loss of the modular teaching of integrated course of metabolism and energy,so as to provide reference for extending the reform of modular teaching and further improving the teaching quality.

Adipose energy stores, physical work, and the metabolic syndrome: lessons from hummingbirds

Directory of Open Access Journals (Sweden)

Hargrove James L

2005-12-01

Full Text Available Abstract Hummingbirds and other nectar-feeding, migratory birds possess unusual adaptive traits that offer important lessons concerning obesity, diabetes and the metabolic syndrome. Hummingbirds consume a high sugar diet and have fasting glucose levels that would be severely hyperglycemic in humans, yet these nectar-fed birds recover most glucose that is filtered into the urine. Hummingbirds accumulate over 40% body fat shortly before migrations in the spring and autumn. Despite hyperglycemia and seasonally elevated body fat, the birds are not known to become diabetic in the sense of developing polyuria (glucosuria, polydipsia and polyphagia. The tiny (3–4 g Ruby-throated hummingbird has among the highest mass-specific metabolic rates known, and loses most of its stored fat in 20 h by flying up to 600 miles across the Gulf of Mexico. During the breeding season, it becomes lean and maintains an extremely accurate energy balance. In addition, hummingbirds can quickly enter torpor and reduce resting metabolic rates by 10-fold. Thus, hummingbirds are wonderful examples of the adaptive nature of fat tissue, and may offer lessons concerning prevention of metabolic syndrome in humans.

Role of resting metabolic rate and energy expenditure in hunger and appetite control: a new formulation.

Science.gov (United States)

Blundell, John E; Caudwell, Phillipa; Gibbons, Catherine; Hopkins, Mark; Naslund, Erik; King, Neil; Finlayson, Graham

2012-09-01

A long-running issue in appetite research concerns the influence of energy expenditure on energy intake. More than 50 years ago, Otto G. Edholm proposed that "the differences between the intakes of food [of individuals] must originate in differences in the expenditure of energy". However, a relationship between energy expenditure and energy intake within any one day could not be found, although there was a correlation over 2 weeks. This issue was never resolved before interest in integrative biology was replaced by molecular biochemistry. Using a psychobiological approach, we have studied appetite control in an energy balance framework using a multi-level experimental system on a single cohort of overweight and obese human subjects. This has disclosed relationships between variables in the domains of body composition [fat-free mass (FFM), fat mass (FM)], metabolism, gastrointestinal hormones, hunger and energy intake. In this Commentary, we review our own and other data, and discuss a new formulation whereby appetite control and energy intake are regulated by energy expenditure. Specifically, we propose that FFM (the largest contributor to resting metabolic rate), but not body mass index or FM, is closely associated with self-determined meal size and daily energy intake. This formulation has implications for understanding weight regulation and the management of obesity.

Quantitative Tools for Dissection of Hydrogen-Producing Metabolic Networks-Final Report

Energy Technology Data Exchange (ETDEWEB)

Rabinowitz, Joshua D.; Dismukes, G.Charles.; Rabitz, Herschel A.; Amador-Noguez, Daniel

2012-10-19

During this project we have pioneered the development of integrated experimental-computational technologies for the quantitative dissection of metabolism in hydrogen and biofuel producing microorganisms (i.e. C. acetobutylicum and various cyanobacteria species). The application of these new methodologies resulted in many significant advances in the understanding of the metabolic networks and metabolism of these organisms, and has provided new strategies to enhance their hydrogen or biofuel producing capabilities. As an example, using mass spectrometry, isotope tracers, and quantitative flux-modeling we mapped the metabolic network structure in C. acetobutylicum. This resulted in a comprehensive and quantitative understanding of central carbon metabolism that could not have been obtained using genomic data alone. We discovered that biofuel production in this bacterium, which only occurs during stationary phase, requires a global remodeling of central metabolism (involving large changes in metabolite concentrations and fluxes) that has the effect of redirecting resources (carbon and reducing power) from biomass production into solvent production. This new holistic, quantitative understanding of metabolism is now being used as the basis for metabolic engineering strategies to improve solvent production in this bacterium. In another example, making use of newly developed technologies for monitoring hydrogen and NAD(P)H levels in vivo, we dissected the metabolic pathways for photobiological hydrogen production by cyanobacteria Cyanothece sp. This investigation led to the identification of multiple targets for improving hydrogen production. Importantly, the quantitative tools and approaches that we have developed are broadly applicable and we are now using them to investigate other important biofuel producers, such as cellulolytic bacteria.

Insight into Energy Conservation via Alternative Carbon Monoxide Metabolism in Carboxydothermus pertinax Revealed by Comparative Genome Analysis.

Science.gov (United States)

Fukuyama, Yuto; Omae, Kimiho; Yoneda, Yasuko; Yoshida, Takashi; Sako, Yoshihiko

2018-05-04

Carboxydothermus species are some of the most studied thermophilic carboxydotrophs. Their varied carboxydotrophic growth properties suggest distinct strategies for energy conservation via CO metabolism. In this study, we used comparative genome analysis of the genus Carboxydothermus to show variations in the CO dehydrogenase/energy-converting hydrogenase gene cluster, which is responsible for CO metabolism with H 2 production (hydrogenogenic CO metabolism). Indeed, ability or inability to produce H 2 with CO oxidation is explained by the presence or absence of this gene cluster in C. hydrogenoformans , C. islandicus , and C. ferrireducens Interestingly, despite its hydrogenogenic CO metabolism, C. pertinax lacks the Ni-CO dehydrogenase catalytic subunit (CooS-I) and its transcriptional regulator encoding genes in this gene cluster probably due to inversion. Transcriptional analysis in C. pertinax showed that the Ni-CO dehydrogenase gene ( cooS-II ) and distantly encoded energy-converting hydrogenase related genes were remarkably upregulated under 100% CO. In addition, when thiosulfate was available as a terminal electron acceptor under 100% CO, C. pertinax maximum cell density and maximum specific growth rate were 3.1-fold and 1.5-fold higher, respectively, than when thiosulfate was absent. The amount of H 2 produced was only 63% of the consumed CO, less than expected according to hydrogenogenic CO oxidation: CO + H 2 O → CO 2 + H 2 Accordingly, C. pertinax would couple CO oxidation by Ni-CO dehydrogenase-II with simultaneous reduction of not only H 2 O but thiosulfate when grown under 100% CO. IMPORTANCE Anaerobic hydrogenogenic carboxydotrophs are thought to fill a vital niche with scavenging potentially toxic CO and producing H 2 as available energy source for thermophilic microbes. This hydrogenogenic carboxydotrophy relies on a Ni-CO dehydrogenase/energy-converting hydrogenase gene cluster. This feature is thought to be as common to these organisms. However

Effects of Dietary Protein Source and Quantity during Weight Loss on Appetite, Energy Expenditure, and Cardio-Metabolic Responses.

Science.gov (United States)

Li, Jia; Armstrong, Cheryl L H; Campbell, Wayne W

2016-01-26

Higher protein meals increase satiety and the thermic effect of feeding (TEF) in acute settings, but it is unclear whether these effects remain after a person becomes acclimated to energy restriction or a given protein intake. This study assessed the effects of predominant protein source (omnivorous, beef/pork vs. lacto-ovo vegetarian, soy/legume) and quantity (10%, 20%, or 30% of energy from protein) on appetite, energy expenditure, and cardio-metabolic indices during energy restriction (ER) in overweight and obese adults. Subjects were randomly assigned to one protein source and then consumed diets with different quantities of protein (4 weeks each) in a randomized crossover manner. Perceived appetite ratings (free-living and in-lab), TEF, and fasting cardio-metabolic indices were assessed at the end of each 4-week period. Protein source and quantity did not affect TEF, hunger, or desire to eat, other than a modestly higher daily composite fullness rating with 30% vs. 10% protein diet (p = 0.03). While the 20% and 30% protein diets reduced cholesterol, triacylglycerol, and APO-B vs. 10% protein (p appetite control, energy expenditure and cardio-metabolic risk factors during ER-induced weight loss.

Role of interleukin 1 and tumor necrosis factor on energy metabolism in rabbits

International Nuclear Information System (INIS)

Tredget, E.E.; Yu, Y.M.; Zhong, S.; Burini, R.; Okusawa, S.; Gelfand, J.A.; Dinarello, C.A.; Young, V.R.; Burke, J.F.

1988-01-01

A study of the combined effects of intravenous infusion of the recombinant cytokines beta-interleukin 1 (IL-1) and alpha-tumor necrosis factor (TNF) on energy substrate metabolism in awake, conditioned, adult rabbits was performed. After a 2-h basal or control period, 48-h fasted rabbits were administered TNF and IL-1 as a bolus (5 micrograms/kg) followed by a continuous intravenous infusion (25 ng.kg-1.min-1) for 3 h. Significant increases in plasma lactate (P less than 0.01), glucose (P less than 0.01), and triglycerides (P less than 0.05) occurred during the combined infusion of IL-1 and TNF, whereas neither cytokine alone had no effect. There was a 33% increase in the rate of glucose appearance (P less than 0.05), but glucose clearance was not altered compared with the control period. Glucose oxidation increased during the combined cytokine infusion period and glucose recycling increased by 600% (P less than 0.002). Lactic acidosis and decreased oxygen consumption, as a result of the cytokine infusions, indicated development of anaerobic glycolytic metabolism. A reduction in the activity state of hepatic mitochondrial pyruvate dehydrogenase (65 vs. 82% in control animals, P less than 0.05) was consistent with the observed increase in anaerobic glycolysis. Thus the combined infusion of IL-1 and TNF in rabbits produces metabolic manifestations seen in severe injury and sepsis in human patients and, as such, may account for the profound alterations of energy metabolism seen in these conditions

Role of interleukin 1 and tumor necrosis factor on energy metabolism in rabbits

Energy Technology Data Exchange (ETDEWEB)

Tredget, E.E.; Yu, Y.M.; Zhong, S.; Burini, R.; Okusawa, S.; Gelfand, J.A.; Dinarello, C.A.; Young, V.R.; Burke, J.F.

1988-12-01

A study of the combined effects of intravenous infusion of the recombinant cytokines beta-interleukin 1 (IL-1) and alpha-tumor necrosis factor (TNF) on energy substrate metabolism in awake, conditioned, adult rabbits was performed. After a 2-h basal or control period, 48-h fasted rabbits were administered TNF and IL-1 as a bolus (5 micrograms/kg) followed by a continuous intravenous infusion (25 ng.kg-1.min-1) for 3 h. Significant increases in plasma lactate (P less than 0.01), glucose (P less than 0.01), and triglycerides (P less than 0.05) occurred during the combined infusion of IL-1 and TNF, whereas neither cytokine alone had no effect. There was a 33% increase in the rate of glucose appearance (P less than 0.05), but glucose clearance was not altered compared with the control period. Glucose oxidation increased during the combined cytokine infusion period and glucose recycling increased by 600% (P less than 0.002). Lactic acidosis and decreased oxygen consumption, as a result of the cytokine infusions, indicated development of anaerobic glycolytic metabolism. A reduction in the activity state of hepatic mitochondrial pyruvate dehydrogenase (65 vs. 82% in control animals, P less than 0.05) was consistent with the observed increase in anaerobic glycolysis. Thus the combined infusion of IL-1 and TNF in rabbits produces metabolic manifestations seen in severe injury and sepsis in human patients and, as such, may account for the profound alterations of energy metabolism seen in these conditions.

Insulin resistance and protein energy metabolism in patients with advanced chronic kidney disease.

Science.gov (United States)

Siew, Edward D; Ikizler, Talat Alp

2010-01-01

Insulin resistance (IR), the reciprocal of insulin sensitivity is a known complication of advanced chronic kidney disease (CKD) and is associated with a number of metabolic derangements. The complex metabolic abnormalities observed in CKD such as vitamin D deficiency, obesity, metabolic acidosis, inflammation, and accumulation of "uremic toxins" are believed to contribute to the etiology of IR and acquired defects in the insulin-receptor signaling pathway in this patient population. Only a few investigations have explored the validity of commonly used assessment methods in comparison to gold standard hyperinsulinemic hyperglycemic clamp technique in CKD patients. An important consequence of insulin resistance is its role in the pathogenesis of protein energy wasting, a state of metabolic derangement characterized by loss of somatic and visceral protein stores not entirely accounted for by inadequate nutrient intake. In the general population, insulin resistance has been associated with accelerated protein catabolism. Among end-stage renal disease (ESRD) patients, enhanced muscle protein breakdown has been observed in patients with Type II diabetes compared to ESRD patients without diabetes. In the absence of diabetes mellitus (DM) or severe obesity, insulin resistance is detectable in dialysis patients and strongly associated with increased muscle protein breakdown, primarily mediated by the ubiquitin-proteasome pathway. Recent epidemiological data indicate a survival advantage and better nutritional status in insulin-free Type II DM patients treated with insulin sensitizer thiazolidinediones. Given the high prevalence of protein energy wasting in ESRD and its unequivocal association with adverse clinical outcomes, insulin resistance may represent an important modifiable target for intervention in the ESRD population.

Altered energy metabolism in an irradiated population of lizards at the Nevada Test Site

International Nuclear Information System (INIS)

Nagy, K.A.; Medica, P.A.

1985-01-01

Field metabolic rates (via doubly labeled water), body compartmentalization of energy stores, and energy assimilation efficiencies were measured to assess all avenues of energy utilization in Uta stansburiana living in a low-level γ-irradiated plot in Rock Valley, Nevada. Comparison of energy budgets for radiation-sterilized females with those of nonirradiated control lizards revealed several substantial differences. Sterile females were heavier, mainly because they had extraordinarily large energy (fat) storage depots. Sterile females had much lower rates of energy expenditure via respiration and lower rates of energy intake by feeding. These differences are interpreted as indirect responses to radiation-induced sterility. There is little evidence of direct radiation effects on physiological functions other than reproduction

Control of mitochondrial metabolism and systemic energy homeostasis by microRNAs 378 and 378*.

Science.gov (United States)

Carrer, Michele; Liu, Ning; Grueter, Chad E; Williams, Andrew H; Frisard, Madlyn I; Hulver, Matthew W; Bassel-Duby, Rhonda; Olson, Eric N

2012-09-18

Obesity and metabolic syndrome are associated with mitochondrial dysfunction and deranged regulation of metabolic genes. Peroxisome proliferator-activated receptor γ coactivator 1β (PGC-1β) is a transcriptional coactivator that regulates metabolism and mitochondrial biogenesis through stimulation of nuclear hormone receptors and other transcription factors. We report that the PGC-1β gene encodes two microRNAs (miRNAs), miR-378 and miR-378*, which counterbalance the metabolic actions of PGC-1β. Mice genetically lacking miR-378 and miR-378* are resistant to high-fat diet-induced obesity and exhibit enhanced mitochondrial fatty acid metabolism and elevated oxidative capacity of insulin-target tissues. Among the many targets of these miRNAs, carnitine O-acetyltransferase, a mitochondrial enzyme involved in fatty acid metabolism, and MED13, a component of the Mediator complex that controls nuclear hormone receptor activity, are repressed by miR-378 and miR-378*, respectively, and are elevated in the livers of miR-378/378* KO mice. Consistent with these targets as contributors to the metabolic actions of miR-378 and miR-378*, previous studies have implicated carnitine O-acetyltransferase and MED13 in metabolic syndrome and obesity. Our findings identify miR-378 and miR-378* as integral components of a regulatory circuit that functions under conditions of metabolic stress to control systemic energy homeostasis and the overall oxidative capacity of insulin target tissues. Thus, these miRNAs provide potential targets for pharmacologic intervention in obesity and metabolic syndrome.

Adipose tissue lipolysis and energy metabolism in early cancer cachexia in mice

Science.gov (United States)

Kliewer, Kara L; Ke, Jia-Yu; Tian, Min; Cole, Rachel M; Andridge, Rebecca R; Belury, Martha A

2015-01-01

Cancer cachexia is a progressive metabolic disorder that results in depletion of adipose tissue and skeletal muscle. A growing body of literature suggests that maintaining adipose tissue mass in cachexia may improve quality-of-life and survival outcomes. Studies of lipid metabolism in cachexia, however, have generally focused on later stages of the disorder when severe loss of adipose tissue has already occurred. Here, we investigated lipid metabolism in adipose, liver and muscle tissues during early stage cachexia – before severe fat loss – in the colon-26 murine model of cachexia. White adipose tissue mass in cachectic mice was moderately reduced (34–42%) and weight loss was less than 10% of initial body weight in this study of early cachexia. In white adipose depots of cachectic mice, we found evidence of enhanced protein kinase A - activated lipolysis which coincided with elevated total energy expenditure and increased expression of markers of brown (but not white) adipose tissue thermogenesis and the acute phase response. Total lipids in liver and muscle were unchanged in early cachexia while markers of fatty oxidation were increased. Many of these initial metabolic responses contrast with reports of lipid metabolism in later stages of cachexia. Our observations suggest intervention studies to preserve fat mass in cachexia should be tailored to the stage of cachexia. Our observations also highlight a need for studies that delineate the contribution of cachexia stage and animal model to altered lipid metabolism in cancer cachexia and identify those that most closely mimic the human condition. PMID:25457061

Role of resting metabolic rate and energy expenditure in hunger and appetite control: a new formulation

Directory of Open Access Journals (Sweden)

John E. Blundell

2012-09-01

Full Text Available A long-running issue in appetite research concerns the influence of energy expenditure on energy intake. More than 50 years ago, Otto G. Edholm proposed that “the differences between the intakes of food [of individuals] must originate in differences in the expenditure of energy”. However, a relationship between energy expenditure and energy intake within any one day could not be found, although there was a correlation over 2 weeks. This issue was never resolved before interest in integrative biology was replaced by molecular biochemistry. Using a psychobiological approach, we have studied appetite control in an energy balance framework using a multi-level experimental system on a single cohort of overweight and obese human subjects. This has disclosed relationships between variables in the domains of body composition [fat-free mass (FFM, fat mass (FM], metabolism, gastrointestinal hormones, hunger and energy intake. In this Commentary, we review our own and other data, and discuss a new formulation whereby appetite control and energy intake are regulated by energy expenditure. Specifically, we propose that FFM (the largest contributor to resting metabolic rate, but not body mass index or FM, is closely associated with self-determined meal size and daily energy intake. This formulation has implications for understanding weight regulation and the management of obesity.

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

Science.gov (United States)

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.

Brazilian energy balance 2011 - year 2010. Final report; Balanco energetico nacional 2011 - ano base 2010. Relatorio final

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

The Brazilian energy balance - BEB - is divided into eight chapters and ten annexes, whose contents are as follow: chapter 1 - Energy Analysis and Aggregated Data - presents energy highlights per source in 2010 and analyses the evolution of the internal offer of energy and its relationship with economic growth in 2010; chapter 2 - Energy Supply and Demand by Source - has the accountancy, per primary and secondary energy sources, of the production, import, export, variation of stocks, losses, adjustments, desegregated total per socioeconomic sector in the country; chapter 3 - Energy Consumption by Sector - presents the final energy consumption classified by primary and secondary source for each sector of the economy; chapter 4 - Energy Imports and Exports - presents the evolution of the data on the import and export of energy and the dependence on external energy; chapter 5 - Balance of Transformation Centers - presents the energy balances for the energy transformation centers including their losses; chapter 6 - Energy Resources and Reserves - has the basic concepts use in the survey of resources and reserves of primary energy sources, with the evolution of the data from 1974 to 2010, through graphs and tables; chapter 7 - Energy and Socioeconomics - contains a comparison of energy, economic and population parameters, specific consumption, energy intensities, average prices and spending on petroleum imports; chapter 8 - State Energy Data - presents energy data for the states by Federal Unit, main energy source production, energy installations, reserves and hydraulic potential. (author)

Interdisciplinary Pathways for Urban Metabolism Research

Science.gov (United States)

Newell, J. P.

2011-12-01

With its rapid rise as a metaphor to express coupled natural-human systems in cities, the concept of urban metabolism is evolving into a series of relatively distinct research frameworks amongst various disciplines, with varying definitions, theories, models, and emphases. In industrial ecology, housed primarily within the disciplinary domain of engineering, urban metabolism research has focused on quantifying material and energy flows into, within, and out of cities, using methodologies such as material flow analysis and life cycle assessment. In the field of urban ecology, which is strongly influenced by ecology and urban planning, research focus has been placed on understanding and modeling the complex patterns and processes of human-ecological systems within urban areas. Finally, in political ecology, closely aligned with human geography and anthropology, scholars theorize about the interwoven knots of social and natural processes, material flows, and spatial structures that form the urban metabolism. This paper offers three potential interdisciplinary urban metabolism research tracks that might integrate elements of these three "ecologies," thereby bridging engineering and the social and physical sciences. First, it presents the idea of infrastructure ecology, which explores the complex, emergent interdependencies between gray (water and wastewater, transportation, etc) and green (e.g. parks, greenways) infrastructure systems, as nested within a broader socio-economic context. For cities to be sustainable and resilient over time-space, the theory follows, these is a need to understand and redesign these infrastructure linkages. Second, there is the concept of an urban-scale carbon metabolism model which integrates consumption-based material flow analysis (including goods, water, and materials), with the carbon sink and source dynamics of the built environment (e.g. buildings, etc) and urban ecosystems. Finally, there is the political ecology of the material

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

Science.gov (United States)

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.

A Transcript-Specific eIF3 Complex Mediates Global Translational Control of Energy Metabolism.

Science.gov (United States)

Shah, Meera; Su, Dan; Scheliga, Judith S; Pluskal, Tomáš; Boronat, Susanna; Motamedchaboki, Khatereh; Campos, Alexandre Rosa; Qi, Feng; Hidalgo, Elena; Yanagida, Mitsuhiro; Wolf, Dieter A

2016-08-16

The multi-subunit eukaryotic translation initiation factor eIF3 is thought to assist in the recruitment of ribosomes to mRNA. The expression of eIF3 subunits is frequently disrupted in human cancers, but the specific roles of individual subunits in mRNA translation and cancer remain elusive. Using global transcriptomic, proteomic, and metabolomic profiling, we found a striking failure of Schizosaccharomyces pombe cells lacking eIF3e and eIF3d to synthesize components of the mitochondrial electron transport chain, leading to a defect in respiration, endogenous oxidative stress, and premature aging. Energy balance was maintained, however, by a switch to glycolysis with increased glucose uptake, upregulation of glycolytic enzymes, and strict dependence on a fermentable carbon source. This metabolic regulatory function appears to be conserved in human cells where eIF3e binds metabolic mRNAs and promotes their translation. Thus, via its eIF3d-eIF3e module, eIF3 orchestrates an mRNA-specific translational mechanism controlling energy metabolism that may be disrupted in cancer. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Adaptive remodeling of skeletal muscle energy metabolism in high-altitude hypoxia: Lessons from AltitudeOmics.

Science.gov (United States)

Chicco, Adam J; Le, Catherine H; Gnaiger, Erich; Dreyer, Hans C; Muyskens, Jonathan B; D'Alessandro, Angelo; Nemkov, Travis; Hocker, Austin D; Prenni, Jessica E; Wolfe, Lisa M; Sindt, Nathan M; Lovering, Andrew T; Subudhi, Andrew W; Roach, Robert C

2018-05-04

Metabolic responses to hypoxia play important roles in cell survival strategies and disease pathogenesis in humans. However, the homeostatic adjustments that balance changes in energy supply and demand to maintain organismal function under chronic low oxygen conditions remain incompletely understood, making it difficult to distinguish adaptive from maladaptive responses in hypoxia-related pathologies. We integrated metabolomic and proteomic profiling with mitochondrial respirometry and blood gas analyses to comprehensively define the physiological responses of skeletal muscle energy metabolism to 16 days of high-altitude hypoxia (5260 m) in healthy volunteers from the AltitudeOmics project. In contrast to the view that hypoxia down-regulates aerobic metabolism, results show that mitochondria play a central role in muscle hypoxia adaptation by supporting higher resting phosphorylation potential and enhancing the efficiency of long-chain acylcarnitine oxidation. This directs increases in muscle glucose toward pentose phosphate and one-carbon metabolism pathways that support cytosolic redox balance and help mitigate the effects of increased protein and purine nucleotide catabolism in hypoxia. Muscle accumulation of free amino acids favor these adjustments by coordinating cytosolic and mitochondrial pathways to rid the cell of excess nitrogen, but might ultimately limit muscle oxidative capacity in vivo Collectively, these studies illustrate how an integration of aerobic and anaerobic metabolism is required for physiological hypoxia adaptation in skeletal muscle, and highlight protein catabolism and allosteric regulation as unexpected orchestrators of metabolic remodeling in this context. These findings have important implications for the management of hypoxia-related diseases and other conditions associated with chronic catabolic stress. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Measuring maximum and standard metabolic rates using intermittent-flow respirometry: a student laboratory investigation of aerobic metabolic scope and environmental hypoxia in aquatic breathers.

Science.gov (United States)

Rosewarne, P J; Wilson, J M; Svendsen, J C

2016-01-01

Metabolic rate is one of the most widely measured physiological traits in animals and may be influenced by both endogenous (e.g. body mass) and exogenous factors (e.g. oxygen availability and temperature). Standard metabolic rate (SMR) and maximum metabolic rate (MMR) are two fundamental physiological variables providing the floor and ceiling in aerobic energy metabolism. The total amount of energy available between these two variables constitutes the aerobic metabolic scope (AMS). A laboratory exercise aimed at an undergraduate level physiology class, which details the appropriate data acquisition methods and calculations to measure oxygen consumption rates in rainbow trout Oncorhynchus mykiss, is presented here. Specifically, the teaching exercise employs intermittent flow respirometry to measure SMR and MMR, derives AMS from the measurements and demonstrates how AMS is affected by environmental oxygen. Students' results typically reveal a decline in AMS in response to environmental hypoxia. The same techniques can be applied to investigate the influence of other key factors on metabolic rate (e.g. temperature and body mass). Discussion of the results develops students' understanding of the mechanisms underlying these fundamental physiological traits and the influence of exogenous factors. More generally, the teaching exercise outlines essential laboratory concepts in addition to metabolic rate calculations, data acquisition and unit conversions that enhance competency in quantitative analysis and reasoning. Finally, the described procedures are generally applicable to other fish species or aquatic breathers such as crustaceans (e.g. crayfish) and provide an alternative to using higher (or more derived) animals to investigate questions related to metabolic physiology. © 2016 The Fisheries Society of the British Isles.

Increasing serotonin concentrations alter calcium and energy metabolism in dairy cows.

Science.gov (United States)

Laporta, Jimena; Moore, Spencer A E; Weaver, Samantha R; Cronick, Callyssa M; Olsen, Megan; Prichard, Austin P; Schnell, Brian P; Crenshaw, Thomas D; Peñagaricano, Francisco; Bruckmaier, Rupert M; Hernandez, Laura L

2015-07-01

A 4×4 Latin square design in which varied doses (0, 0.5, 1.0, and 1.5 mg/kg) of 5-hydroxy-l-tryptophan (5-HTP, a serotonin precursor) were intravenously infused into late-lactation, non-pregnant Holstein dairy cows was used to determine the effects of serotonin on calcium and energy metabolism. Infusion periods lasted 4 days, with a 5-day washout between periods. Cows were infused at a constant rate for 1 h each day. Blood was collected pre- and 5, 10, 30, 60, 90, and 120 min post-infusion, urine was collected pre- and post-infusion, and milk was collected daily. All of the 5-HTP doses increased systemic serotonin as compared to the 0 mg/kg dose, and the 1.0 and 1.5 mg/kg doses increased circulating glucose and non-esterified fatty acids (NEFA) and decreased beta-hydroxybutyrate (βHBA) concentrations. Treatment of cows with either 1.0 or 1.5 mg/kg 5-HTP doses decreased urine calcium elimination, and the 1.5 mg/kg dose increased milk calcium concentrations. No differences were detected in the heart rates, respiration rates, or body temperatures of the cows; however, manure scores and defecation frequency were affected. Indeed, cows that received 5-HTP defecated more, and the consistency of their manure was softer. Treatment of late-lactation dairy cows with 5-HTP improved energy metabolism, decreased loss of calcium into urine, and increased calcium secretion into milk. Further research should target the effects of increasing serotonin during the transition period to determine any benefits for post-parturient calcium and glucose metabolism. © 2015 Society for Endocrinology.

Altered metabolism in cancer

Directory of Open Access Journals (Sweden)

Locasale Jason W

2010-06-01

Full Text Available Abstract Cancer cells have different metabolic requirements from their normal counterparts. Understanding the consequences of this differential metabolism requires a detailed understanding of glucose metabolism and its relation to energy production in cancer cells. A recent study in BMC Systems Biology by Vasquez et al. developed a mathematical model to assess some features of this altered metabolism. Here, we take a broader look at the regulation of energy metabolism in cancer cells, considering their anabolic as well as catabolic needs. See research article: http://www.biomedcentral.com/1752-0509/4/58/

Research and development on super heat pump energy accumulation system. Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1993-06-01

This is the final report on research and development of super heat pump energy accumulation system, which has been carried out from FY 1985 to 1992. It describes outline of the research and development program, R and D results, final evaluation methodology, evaluation of the R and D, proposals for the commercialization, and so on. The super high performance compression heat pumps are technically evaluated for highly efficient type (for heating, and cooling and heating), high temperature type (utilizing high temperature heat source, and low temperature heat source), working fluids (alcohol-based and nonalcohol-based), stainless steel plate fin type heat exchanger, EHD heat exchanger, and so on. The other techniques evaluated include those for chemical heat storage, combined systems, plant simulation, and systemization. The evaluation works are also directed to the economic and environmental aspects. Finally, the R and D themes are proposed to leap over various hurdles, e.g., reliability and economic viability, for the eventual commercialization of the energy accumulation system. (NEDO)

Comprehensive metabolic characterization of serum osteocalcin action in a large non-diabetic sample.

Directory of Open Access Journals (Sweden)

Lukas Entenmann

Full Text Available Recent research suggested a metabolic implication of osteocalcin (OCN in e.g. insulin sensitivity or steroid production. We used an untargeted metabolomics approach by analyzing plasma and urine samples of 931 participants using mass spectrometry to reveal further metabolic actions of OCN. Several detected relations between OCN and metabolites were strongly linked to renal function, however, a number of associations remained significant after adjustment for renal function. Intermediates of proline catabolism were associated with OCN reflecting the implication in bone metabolism. The association to kynurenine points towards a pro-inflammatory state with increasing OCN. Inverse relations with intermediates of branch-chained amino acid metabolism suggest a link to energy metabolism. Finally, urinary surrogate markers of smoking highlight its adverse effect on OCN metabolism. In conclusion, the present study provides a read-out of metabolic actions of OCN. However, most of the associations were weak arguing for a limited role of OCN in whole-body metabolism.

Comprehensive metabolic characterization of serum osteocalcin action in a large non-diabetic sample.

Science.gov (United States)

Entenmann, Lukas; Pietzner, Maik; Artati, Anna; Hannemann, Anke; Henning, Ann-Kristin; Kastenmüller, Gabi; Völzke, Henry; Nauck, Matthias; Adamski, Jerzy; Wallaschofski, Henri; Friedrich, Nele

2017-01-01

Recent research suggested a metabolic implication of osteocalcin (OCN) in e.g. insulin sensitivity or steroid production. We used an untargeted metabolomics approach by analyzing plasma and urine samples of 931 participants using mass spectrometry to reveal further metabolic actions of OCN. Several detected relations between OCN and metabolites were strongly linked to renal function, however, a number of associations remained significant after adjustment for renal function. Intermediates of proline catabolism were associated with OCN reflecting the implication in bone metabolism. The association to kynurenine points towards a pro-inflammatory state with increasing OCN. Inverse relations with intermediates of branch-chained amino acid metabolism suggest a link to energy metabolism. Finally, urinary surrogate markers of smoking highlight its adverse effect on OCN metabolism. In conclusion, the present study provides a read-out of metabolic actions of OCN. However, most of the associations were weak arguing for a limited role of OCN in whole-body metabolism.

Regulation of neurotrophic factors and energy metabolism by antidepressants in astrocytes

KAUST Repository

Martin, Jean Luc; Magistretti, Pierre J.; Allaman, Igor

2013-01-01

There is growing evidence that astrocytes are involved in the neuropathology of major depression. In particular, decreases in glial cell density observed in the cerebral cortex of individuals with major depressive disorder are accompanied by a reduction of several astrocytic markers suggesting that astrocyte dysfunction may contribute to the pathophysiology of major depression. In rodents, glial loss in the prefrontal cortex is sufficient to induce depressive-like behaviors and antidepressant treatment prevents the stress-induced reduction of astrocyte number in the hippocampus. Collectively, these data support the existence of a link between astrocyte loss or dysfunction, depressive-like behavior and antidepressant treatment. Astrocytes are increasingly recognized to play important roles in neuronal development, neurotransmission, synaptic plasticity and maintenance of brain homeostasis. It is also well established that astrocytes provide trophic, structural, and metabolic support to neurons. In this article, we review evidence that antidepressants regulate energy metabolism and neurotrophic factor expression with particular emphasis on studies in astrocytes. These observations support a role for astrocytes as new targets for antidepressants. The contribution of changes in astrocyte glucose metabolism and neurotrophic factor expression to the therapeutic effects of antidepressants remains to be established. © 2013 Bentham Science Publishers.

Regulation of neurotrophic factors and energy metabolism by antidepressants in astrocytes

KAUST Repository

Martin, Jean Luc

2013-09-01

There is growing evidence that astrocytes are involved in the neuropathology of major depression. In particular, decreases in glial cell density observed in the cerebral cortex of individuals with major depressive disorder are accompanied by a reduction of several astrocytic markers suggesting that astrocyte dysfunction may contribute to the pathophysiology of major depression. In rodents, glial loss in the prefrontal cortex is sufficient to induce depressive-like behaviors and antidepressant treatment prevents the stress-induced reduction of astrocyte number in the hippocampus. Collectively, these data support the existence of a link between astrocyte loss or dysfunction, depressive-like behavior and antidepressant treatment. Astrocytes are increasingly recognized to play important roles in neuronal development, neurotransmission, synaptic plasticity and maintenance of brain homeostasis. It is also well established that astrocytes provide trophic, structural, and metabolic support to neurons. In this article, we review evidence that antidepressants regulate energy metabolism and neurotrophic factor expression with particular emphasis on studies in astrocytes. These observations support a role for astrocytes as new targets for antidepressants. The contribution of changes in astrocyte glucose metabolism and neurotrophic factor expression to the therapeutic effects of antidepressants remains to be established. © 2013 Bentham Science Publishers.

Rethinking Energy in Parkinsonian Motor Symptoms: A Potential Role for Neural Metabolic Deficits

Directory of Open Access Journals (Sweden)

Shinichi eAmano

2015-01-01

Full Text Available Parkinson’s disease (PD is characterized as a chronic and progressive neurodegenerative disorder that results in a variety of debilitating symptoms, including bradykinesia, resting tremor, rigidity, and postural instability. Research spanning several decades has emphasized basal ganglia dysfunction, predominantly resulting from dopaminergic cell loss, as the primarily cause of the aforementioned parkinsonian features. But, why those particular features manifest themselves remains an enigma. The goal of this paper is to develop a theoretical framework that parkinsonian motor features are behavioral consequence of a long-term adaptation to their inability (inflexibility or lack of capacity to meet energetic demands, due to neural metabolic deficits arising from mitochondrial dysfunction associated with PD. Here, we discuss neurophysiological changes that are generally associated with PD, such as selective degeneration of dopaminergic neurons in the substantia nigra pars compacta, in conjunction with metabolic and mitochondrial dysfunction. We then characterize the cardinal motor symptoms of PD, bradykinesia, resting tremor, rigidity and gait disturbance, reviewing literature to demonstrate how these motor patterns are actually energy efficient from a metabolic perspective. We will also develop three testable hypotheses: (1 neural metabolic deficits precede the increased rate of neurodegeneration and onset of behavioral symptoms in PD, (2 motor behavior of persons with PD are more sensitive to changes in metabolic/bioenergetic state, and (3 improvement of metabolic function could lead to better motor performance in persons with PD. These hypotheses are designed to introduce a novel viewpoint that can elucidate the connections between metabolic, neural and motor function in PD.

NAD(H) and NADP(H) Redox Couples and Cellular Energy Metabolism.

Science.gov (United States)

Xiao, Wusheng; Wang, Rui-Sheng; Handy, Diane E; Loscalzo, Joseph

2018-01-20

The nicotinamide adenine dinucleotide (NAD + )/reduced NAD + (NADH) and NADP + /reduced NADP + (NADPH) redox couples are essential for maintaining cellular redox homeostasis and for modulating numerous biological events, including cellular metabolism. Deficiency or imbalance of these two redox couples has been associated with many pathological disorders. Recent Advances: Newly identified biosynthetic enzymes and newly developed genetically encoded biosensors enable us to understand better how cells maintain compartmentalized NAD(H) and NADP(H) pools. The concept of redox stress (oxidative and reductive stress) reflected by changes in NAD(H)/NADP(H) has increasingly gained attention. The emerging roles of NAD + -consuming proteins in regulating cellular redox and metabolic homeostasis are active research topics. The biosynthesis and distribution of cellular NAD(H) and NADP(H) are highly compartmentalized. It is critical to understand how cells maintain the steady levels of these redox couple pools to ensure their normal functions and simultaneously avoid inducing redox stress. In addition, it is essential to understand how NAD(H)- and NADP(H)-utilizing enzymes interact with other signaling pathways, such as those regulated by hypoxia-inducible factor, to maintain cellular redox homeostasis and energy metabolism. Additional studies are needed to investigate the inter-relationships among compartmentalized NAD(H)/NADP(H) pools and how these two dinucleotide redox couples collaboratively regulate cellular redox states and cellular metabolism under normal and pathological conditions. Furthermore, recent studies suggest the utility of using pharmacological interventions or nutrient-based bioactive NAD + precursors as therapeutic interventions for metabolic diseases. Thus, a better understanding of the cellular functions of NAD(H) and NADP(H) may facilitate efforts to address a host of pathological disorders effectively. Antioxid. Redox Signal. 28, 251-272.

Energy metabolism of synaptosomes from different neuronal systems of rat cerebellum during aging: a functional proteomic characterization.

Science.gov (United States)

Ferrari, Federica; Gorini, Antonella; Villa, Roberto Federico

2015-01-01

Functional proteomics was used to characterize age-related changes in energy metabolism of different neuronal pathways within the cerebellar cortex of Wistar rats aged 2, 6, 12, 18, and 24 months. The "large" synaptosomes, derived from the glutamatergic mossy fibre endings which make synaptic contact with the granule cells of the granular layer, and the "small" synaptosomes, derived from the pre-synaptic terminals of granule cells making synaptic contact with the dendrites of Purkinje cells, were isolated by a combined differential/gradient centrifugation technique. Because most brain disorders are associated with bioenergetic changes, the maximum rate (Vmax) of selected enzymes of glycolysis, Krebs' cycle, glutamate and amino acids metabolism, and acetylcholine catabolism were evaluated. The results show that "large" and "small" synaptosomes possess specific and independent metabolic features. This study represents a reliable model to study in vivo (1) the physiopathological molecular mechanisms of some brain diseases dependent on energy metabolism, (2) the responsiveness to noxious stimuli, and (3) the effects of drugs, discriminating their action sites at subcellular level on specific neuronal pathways.

Genome scale metabolic modeling of cancer

DEFF Research Database (Denmark)

Nilsson, Avlant; Nielsen, Jens

2017-01-01

of metabolism which allows simulation and hypotheses testing of metabolic strategies. It has successfully been applied to many microorganisms and is now used to study cancer metabolism. Generic models of human metabolism have been reconstructed based on the existence of metabolic genes in the human genome......Cancer cells reprogram metabolism to support rapid proliferation and survival. Energy metabolism is particularly important for growth and genes encoding enzymes involved in energy metabolism are frequently altered in cancer cells. A genome scale metabolic model (GEM) is a mathematical formalization...

Effect of dietary energy and polymorphisms in BRAP and GHRL on obesity and metabolic traits.

Science.gov (United States)

Imaizumi, Takahiro; Ando, Masahiko; Nakatochi, Masahiro; Yasuda, Yoshinari; Honda, Hiroyuki; Kuwatsuka, Yachiyo; Kato, Sawako; Kondo, Takaaki; Iwata, Masamitsu; Nakashima, Toru; Yasui, Hiroshi; Takamatsu, Hideki; Okajima, Hiroshi; Yoshida, Yasuko; Maruyama, Shoichi

Obesity, a risk factor for all-cause and cardiovascular mortality, is a major health concerns among middle-aged men. The aim of this study was to investigate a possible association of dietary habits and obesity related single nucleotide polymorphisms (SNPs) with obesity and metabolic abnormalities. We conducted a retrospective cohort study using annual health examination data of 5112 male workers, obtained between 2007 and 2011. Average dietary energy was estimated using electronically collected meal purchase data from cafeteria. We examined 8 SNPs related to obesity: GHRL rs696217, PPARG rs1175544, ADIPOQ rs2241766, ADIPOQ rs1501299, PPARD rs2016520, APOA5 rs662799, BRAP rs3782886, and ITGB2 rs235326. We also examined whether SNPs that were shown to associate with obesity affect other metabolic abnormalities such as blood pressure (BP), glucose, and lipid profile. Average dietary energy significantly associated with increased abdominal circumference (AC) and body mass index (BMI). The odds ratios (ORs) of overweight and obesity also increased. The major allele of rs696217 significantly increased BMI and an increased OR with obesity, while the minor allele of rs3782886 was associated with significantly decreased AC and the decreased ORs with overweight and obesity. The minor allele of rs3782886 was also associated with significantly decreased systolic BP (SBP), triglyceride (TG), high-density lipoprotein (HDL), and fasting blood sugar (FBS), while rs696217 was not associated with other metabolic abnormalities. Average dietary energy in lunch, rs3782886, and rs696217 were associated with obesity, and rs3782886 was associated with other metabolic abnormalities. Copyright © 2016 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.

Changes in the carbohydrate-energy metabolism with radiation-induced intestine syndrome

International Nuclear Information System (INIS)

Kendysh, I.N.; Grozdov, S.P.

1981-01-01

A local exposure of the rat abdomen in a dose of 3.6 cC/kg decreases the oxygen uptake, oxidation of glucose and fatty acids, glucose tolerance and insulin resistance, and also causes a trend toward lactic acidosis. These changes in the carbohydrate-energy metabolism are normalized with the administration of insulin and dichloracetate, and they may be interpreted as consequences of a shock provoked by a massive predominant injury to the intestine [ru

Physiological aspects of energy metabolism and gastrointestinal effects of carbohydrates.

Science.gov (United States)

Elia, M; Cummings, J H

2007-12-01

The energy values of carbohydrates continue to be debated. This is because of the use of different energy systems, for example, combustible, digestible, metabolizable, and so on. Furthermore, ingested macronutrients may not be fully available to tissues, and the tissues themselves may not be able fully to oxidize substrates made available to them. Therefore, for certain carbohydrates, the discrepancies between combustible energy (cEI), digestible energy (DE), metabolizable energy (ME) and net metabolizable energy (NME) may be considerable. Three food energy systems are in use in food tables and for food labelling in different world regions based on selective interpretation of the digestive physiology and metabolism of food carbohydrates. This is clearly unsatisfactory and confusing to the consumer. While it has been suggested that an enormous amount of work would have to be undertaken to change the current ME system into an NME system, the additional changes may not be as great as anticipated. In experimental work, carbohydrate is high in the macronutrient hierarchy of satiation. However, studies of eating behaviour indicate that it does not unconditionally depend on the oxidation of one nutrient, and argue against the operation of a simple carbohydrate oxidation or storage model of feeding behaviour to the exclusion of other macronutrients. The site, rate and extent of carbohydrate digestion in, and absorption from the gut are key to understanding the many roles of carbohydrate, although the concept of digestibility has different meanings. Within the nutrition community, the characteristic patterns of digestion that occur in the small (upper) vs large (lower) bowel are known to impact in contrasting ways on metabolism, while in the discussion of the energy value of foods, digestibility is defined as the proportion of combustible energy that is absorbed over the entire length of the gastrointestinal tract. Carbohydrates that reach the large bowel are fermented to

Comparison Between Cerebral Tissue Oxygen Tension and Energy Metabolism in Experimental Subdural Hematoma

DEFF Research Database (Denmark)

Nielsen, Troels Halfeld; Engell, Susanne I; Johnsen, Rikke Aagaard

2011-01-01

BACKGROUND: An experimental swine model (n = 7) simulating an acute subdural hematoma (ASDH) was employed (1) to explore the relation between the brain tissue oxygenation (PbtO(2)) and the regional cerebral energy metabolism as obtained by microdialysis, and (2) to define the lowest level of PbtO(2...

Final Report for NIREC Renewable Energy Research & Development Project

Energy Technology Data Exchange (ETDEWEB)

Borland, Walt [Nevada Institute for Renewable Energy Commercialization (NIREC), Las Vegas, NV (United States)

2017-05-02

This report is a compilation of progress reports and presentations submitted by NIREC to the DOE’s Solar Energy Technologies Office for award number DE-FG36-08GO88161. This compilation has been uploaded to OSTI by DOE as a substitute for the required Final Technical Report, which was not submitted to DOE by NIREC or received by DOE. Project Objective: The primary goal of NIREC is to advance the transformation of the scientific innovation of the institutional partner’s research in renewable energy into a proof of the scientific concept eventually leading to viable businesses with cost effective solutions to accelerate the widespread adoption of renewable energy. NIREC will a) select research projects that are determined to have significant commercialization potential as a result of vetting by the Technology and commercialization Advisory Board, b) assign an experienced Entrepreneur-in-Residence (EIR) to each manage the scientific commercialization-preparedness process, and c) facilitate connectivity with venture capital and other private-sector capital sources to fund the rollout, scaling and growth of the resultant renewable energy business.

Energy Metabolism of the Brain, Including the Cooperation between Astrocytes and Neurons, Especially in the Context of Glycogen Metabolism

OpenAIRE

Falkowska, Anna; Gutowska, Izabela; Goschorska, Marta; Nowacki, Przemys?aw; Chlubek, Dariusz; Baranowska-Bosiacka, Irena

2015-01-01

Glycogen metabolism has important implications for the functioning of the brain, especially the cooperation between astrocytes and neurons. According to various research data, in a glycogen deficiency (for example during hypoglycemia) glycogen supplies are used to generate lactate, which is then transported to neighboring neurons. Likewise, during periods of intense activity of the nervous system, when the energy demand exceeds supply, astrocyte glycogen is immediately converted to lactate, s...

The Essential Role of Cholesterol Metabolism in the Intracellular Survival of Mycobacterium leprae Is Not Coupled to Central Carbon Metabolism and Energy Production.

Science.gov (United States)

Marques, Maria Angela M; Berrêdo-Pinho, Marcia; Rosa, Thabatta L S A; Pujari, Venugopal; Lemes, Robertha M R; Lery, Leticia M S; Silva, Carlos Adriano M; Guimarães, Ana Carolina R; Atella, Georgia C; Wheat, William H; Brennan, Patrick J; Crick, Dean C; Belisle, John T; Pessolani, Maria Cristina V

2015-12-01

Mycobacterium leprae induces the formation of lipid droplets, which are recruited to pathogen-containing phagosomes in infected macrophages and Schwann cells. Cholesterol is among the lipids with increased abundance in M. leprae-infected cells, and intracellular survival relies on cholesterol accumulation. The present study investigated the capacity of M. leprae to acquire and metabolize cholesterol. In silico analyses showed that oxidation of cholesterol to cholest-4-en-3-one (cholestenone), the first step of cholesterol degradation catalyzed by the enzyme 3β-hydroxysteroid dehydrogenase (3β-HSD), is apparently the only portion of the cholesterol catabolic pathway seen in Mycobacterium tuberculosis preserved by M. leprae. Incubation of bacteria with radiolabeled cholesterol confirmed the in silico predictions. Radiorespirometry and lipid analyses performed after incubating M. leprae with [4-(14)C]cholesterol or [26-(14)C]cholesterol showed the inability of this pathogen to metabolize the sterol rings or the side chain of cholesterol as a source of energy and carbon. However, the bacteria avidly incorporated cholesterol and, as expected, converted it to cholestenone both in vitro and in vivo. Our data indicate that M. leprae has lost the capacity to degrade and utilize cholesterol as a nutritional source but retains the enzyme responsible for its oxidation to cholestenone. Thus, the essential role of cholesterol metabolism in the intracellular survival of M. leprae is uncoupled from central carbon metabolism and energy production. Further elucidation of cholesterol metabolism in the host cell during M. leprae infection will establish the mechanism by which this lipid supports M. leprae intracellular survival and will open new avenues for novel leprosy therapies. Our study focused on the obligate intracellular pathogen Mycobacterium leprae and its capacity to metabolize cholesterol. The data make an important contribution for those interested in understanding the

Genetic dissection in a mouse model reveals interactions between carotenoids and lipid metabolism[S

Science.gov (United States)

Palczewski, Grzegorz; Widjaja-Adhi, M. Airanthi K.; Amengual, Jaume; Golczak, Marcin; von Lintig, Johannes

2016-01-01

Carotenoids affect a rich variety of physiological functions in nature and are beneficial for human health. However, knowledge about their biological action and the consequences of their dietary accumulation in mammals is limited. Progress in this research field is limited by the expeditious metabolism of carotenoids in rodents and the confounding production of apocarotenoid signaling molecules. Herein, we established a mouse model lacking the enzymes responsible for carotenoid catabolism and apocarotenoid production, fed on either a β-carotene- or a zeaxanthin-enriched diet. Applying a genome wide microarray analysis, we assessed the effects of the parent carotenoids on the liver transcriptome. Our analysis documented changes in pathways for liver lipid metabolism and mitochondrial respiration. We biochemically defined these effects, and observed that β-carotene accumulation resulted in an elevation of liver triglycerides and liver cholesterol, while zeaxanthin accumulation increased serum cholesterol levels. We further show that carotenoids were predominantly transported within HDL particles in the serum of mice. Finally, we provide evidence that carotenoid accumulation influenced whole-body respiration and energy expenditure. Thus, we observed that accumulation of parent carotenoids interacts with lipid metabolism and that structurally related carotenoids display distinct biological functions in mammals. PMID:27389691

Acetate formation in the energy metabolism of parasitic helminths and protists.

Science.gov (United States)

Tielens, Aloysius G M; van Grinsven, Koen W A; Henze, Katrin; van Hellemond, Jaap J; Martin, William

2010-03-15

Formation and excretion of acetate as a metabolic end product of energy metabolism occurs in many protist and helminth parasites, such as the parasitic helminths Fasciola hepatica, Haemonchus contortus and Ascaris suum, and the protist parasites, Giardia lamblia, Entamoeba histolytica, Trichomonas vaginalis as well as Trypanosoma and Leishmania spp. In all of these parasites acetate is a main end product of their energy metabolism, whereas acetate formation does not occur in their mammalian hosts. Acetate production might therefore harbour novel targets for the development of new anti-parasitic drugs. In parasites, acetate is produced from acetyl-CoA by two different reactions, both involving substrate level phosphorylation, that are catalysed by either a cytosolic acetyl-CoA synthetase (ACS) or an organellar acetate:succinate CoA-transferase (ASCT). The ACS reaction is directly coupled to ATP synthesis, whereas the ASCT reaction yields succinyl-CoA for ATP formation via succinyl-CoA synthetase (SCS). Based on recent work on the ASCTs of F. hepatica, T. vaginalis and Trypanosoma brucei we suggest the existence of three subfamilies of enzymes within the CoA-transferase family I. Enzymes of these three subfamilies catalyse the ASCT reaction in eukaryotes via the same mechanism, but the subfamilies share little sequence homology. The CoA-transferases of the three subfamilies are all present inside ATP-producing organelles of parasites, those of subfamily IA in the mitochondria of trypanosomatids, subfamily IB in the mitochondria of parasitic worms and subfamily IC in hydrogenosome-bearing parasites. Together with the recent characterisation among non-parasitic protists of yet a third route of acetate formation involving acetate kinase (ACK) and phosphotransacetylase (PTA) that was previously unknown among eukaryotes, these recent developments provide a good opportunity to have a closer look at eukaryotic acetate formation. (c) 2010 Australian Society for Parasitology

Brain energy metabolism and blood flow differences in healthy aging

DEFF Research Database (Denmark)

Aanerud, Joel; Borghammer, Per; Chakravarty, M Mallar

2012-01-01

Cerebral metabolic rate of oxygen consumption (CMRO(2)), cerebral blood flow (CBF), and oxygen extraction fraction (OEF) are important indices of healthy aging of the brain. Although a frequent topic of study, changes of CBF and CMRO(2) during normal aging are still controversial, as some authors......, and in the temporal cortex. Because of the inverse relation between OEF and capillary oxygen tension, increased OEF can compromise oxygen delivery to neurons, with possible perturbation of energy turnover. The results establish a possible mechanism of progression from healthy to unhealthy brain aging, as the regions...

Effects of an energy-dense diet and nicotinic acid supplementation on production and metabolic variables of primiparous or multiparous cows in periparturient period.

Science.gov (United States)

Tienken, Reka; Kersten, Susanne; Frahm, Jana; Meyer, Ulrich; Locher, Lena; Rehage, Jürgen; Huber, Korinna; Kenéz, Ákos; Sauerwein, Helga; Mielenz, Manfred; Dänicke, Sven

2015-01-01

It is well observed that feeding energy-dense diets in dairy cows during the dry period can cause metabolic imbalances after parturition. Especially dairy cows with high body condition score (BCS) and fed an energy-dense diet were prone to develop production diseases due to metabolic disturbances postpartum. An experiment was conducted to determine the effects of an energy-dense diet and nicotinic acid (NA) on production and metabolic variables of primiparous and multiparous cows in late pregnancy and early lactation which were not pre-selected for high BCS. Thirty-six multiparous and 20 primiparous German Holstein cows with equal body conditions were fed with energy-dense (60% concentrate/40% roughage mixture; HC group) or adequate (30% concentrate/70% roughage mixture; LC group) diets prepartum. After parturition, concentrate proportion was dropped to 30% for all HC and LC groups and was increased to 50% within 16 days for LC and within 24 days for HC cows. In addition, half of the cows per group received 24 g NA supplement per day and cow aimed to attenuate the lipid mobilisation postpartum. Feeding energy-dense diets to late-pregnant dairy cows elevated the dry matter (p metabolic deviation postpartum as the effects of prepartum concentrate feeding were not carried over into postpartum period. Multiparous cows responded more profoundly to energy-dense feeding prepartum compared with primiparous cows, and parity-related differences in the transition from late pregnancy to lactation were obvious pre- and postpartum. The supplementation with 24 g NA did not reveal any effect on energy metabolism. This study clearly showed that energy-dense feeding prepartum did not result in metabolic imbalances postpartum in multiparous and primiparous cows not selected for high BCS. A genetic predisposition for an anabolic metabolic status as indicated by high BCS may be crucial for developing production diseases at the onset of lactation.

Fatty acid metabolism: target for metabolic syndrome

OpenAIRE

Wakil, Salih J.; Abu-Elheiga, Lutfi A.

2009-01-01

Fatty acids are a major energy source and important constituents of membrane lipids, and they serve as cellular signaling molecules that play an important role in the etiology of the metabolic syndrome. Acetyl-CoA carboxylases 1 and 2 (ACC1 and ACC2) catalyze the synthesis of malonyl-CoA, the substrate for fatty acid synthesis and the regulator of fatty acid oxidation. They are highly regulated and play important roles in the energy metabolism of fatty acids in animals, including humans. They...

Effect of carbon/nitrogen ratio on carbohydrate metabolism and light energy dissipation mechanisms in Arabidopsis thaliana.

Science.gov (United States)

Huarancca Reyes, Thais; Scartazza, Andrea; Lu, Yu; Yamaguchi, Junji; Guglielminetti, Lorenzo

2016-08-01

Carbon (C) and nitrogen (N) nutrient sources are essential elements for metabolism, and their availability must be tightly coordinated for the optimal growth and development in plants. Plants are able to sense and respond to different C/N conditions via specific partitioning of C and N sources and the regulation of a complex cellular metabolic activity. We studied how the interaction between C and N signaling could affect carbohydrate metabolism, soluble sugar levels, photochemical efficiency of photosystem II (PSII) and the ability to drive the excess energy in Arabidopsis seedlings under moderated and disrupted C/N-nutrient conditions. Invertase and sucrose synthase activities were markedly affected by C/N-nutrient status depending on the phosphorylation status, suggesting that these enzymes may necessarily be modulated by their direct phosphorylation or phosphorylation of proteins that form complex with them in response to C/N stress. In addition, the enzymatic activity of these enzymes was also correlated with the amount of sugars, which not only act as substrate but also as signaling compounds. Analysis of chlorophyll fluorescence in plants under disrupted C/N condition suggested a reduction of electron transport rate at PSII level associated with a higher capacity for non-radiative energy dissipation in comparison with plants under moderated C/N condition. In conclusion, the tight coordination between C and N not only affects the carbohydrates metabolism and their concentration within plant tissues, but also the partitioning of the excitation energy at PSII level between radiative (electron transport) and non-radiative (heat) dissipation pathways. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Final report, Feedback limitations of photosynthesis

Energy Technology Data Exchange (ETDEWEB)

Sharkey, Thomas D.

1999-07-22

Final report of research on carbon metabolism of photosynthesis. The feedback from carbon metabolism to primary photosynthetic processes is summarized, and a comprehensive list of published scientific papers is provided.

Energy metabolism in rat mast cells in relation to histamine secretion

DEFF Research Database (Denmark)

Johansen, T

1987-01-01

1. The relation between the energy metabolism and the secretory activity of rat peritoneal mast cells has been studied by determination of the cellular content of ATP and the rate of lactate production reflecting the rate of ATP synthesis under various experimental conditions. Secretion...... and the cellular ATP content at the time of cell activation was demonstrated. This may indicate a direct link between ATP and the secretory mechanism. 3. The possibility of an increased utilization of ATP during histamine secretion was explored in mast cells exposed to metabolic inhibitors. Incubation of mast...... cells with 2-deoxyglucose (2-DG) decreased the ATP content of the cells, and a long-lasting and stable level of mast cell ATP was observed. This is explained by a small decrease in the rate of ATP-synthesis by 2-DG. In 2-DG-treated cells secretion of histamine in response to compound 48...

Restriction on an energy-dense diet improves markers of metabolic health and cellular aging in mice through decreasing hepatic mTOR activity.

Science.gov (United States)

Schloesser, Anke; Campbell, Graeme; Glüer, Claus-Christian; Rimbach, Gerald; Huebbe, Patricia

2015-02-01

Dietary restriction (DR) on a normal low-fat diet improves metabolic health and may prolong life span. However, it is still uncertain whether restriction of an energy-dense, high-fat diet would also be beneficial and mitigate age-related processes. In the present study, we determined biomarkers of metabolic health, energy metabolism, and cellular aging in obesity-prone mice subjected to 30% DR on a high-fat diet for 6 months. Dietary-restricted mice had significantly lower body weights, less adipose tissue, lower energy expenditure, and altered substrate oxidation compared to their ad libitum-fed counterparts. Hepatic major urinary proteins (Mup) expression, which is linked to glucose and energy metabolism, and biomarkers of metabolic health, including insulin, glucose, cholesterol, and leptin/adiponectin ratio, were likewise reduced in high-fat, dietary-restricted mice. Hallmarks of cellular senescence such as Lamp2a and Hsc70 that mediate chaperone-mediated autophagy were induced and mechanistic target of rapamycin (mTOR) signaling mitigated upon high-fat DR. In contrast to DR applied in low-fat diets, anti-oxidant gene expression, proteasome activity, as well as 5'-adenosine monophosphate-activated protein kinase (AMPK) activation were not changed, suggesting that high-fat DR may attenuate some processes associated with cellular aging without the induction of cellular stress response or energy deprivation.

Prenatal programming in an obese swine model: sex-related effects of maternal energy restriction on morphology, metabolism and hypothalamic gene expression.

Science.gov (United States)

Óvilo, Cristina; González-Bulnes, Antonio; Benítez, Rita; Ayuso, Miriam; Barbero, Alicia; Pérez-Solana, Maria L; Barragán, Carmen; Astiz, Susana; Fernández, Almudena; López-Bote, Clemente

2014-02-01

Maternal energy restriction during pregnancy predisposes to metabolic alterations in the offspring. The present study was designed to evaluate phenotypic and metabolic consequences following maternal undernutrition in an obese pig model and to define the potential role of hypothalamic gene expression in programming effects. Iberian sows were fed a control or a 50 % restricted diet for the last two-thirds of gestation. Newborns were assessed for body and organ weights, hormonal and metabolic status, and hypothalamic expression of genes implicated in energy homeostasis, glucocorticoid function and methylation. Weight and adiposity were measured in adult littermates. Newborns of the restricted sows were lighter (P control newborns of both the sexes (P metabolic stress by nutrient insufficiency. A lower hypothalamic expression of anorexigenic peptides (LEPR and POMC, P controls (Pmetabolic alterations in the offspring. Differences in gene expression at birth and higher growth and adiposity in adulthood suggest a female-specific programming effect for a positive energy balance, possibly due to overexposure to endogenous stress-induced glucocorticoids.

Redistribution of whole-body energy metabolism by exercise. A positron emission tomography study

International Nuclear Information System (INIS)

Masud, M.M.; Miyake, Masayasu; Watanuki, Shoichi; Itoh, Masatoshi; Tashiro, Manabu; Fujimoto, Toshihiko

2009-01-01

Our aim was to evaluate changes in glucose metabolism of skeletal muscles and viscera induced by different workloads using 18 F-2-fluoro-2-deoxyglucose ([ 18 F]FDG) and three-dimensional positron emission tomography (3-D PET). Five male volunteers performed ergometer bicycle exercise for 40 min at 40% and 70% of the maximal O 2 consumption (VO 2max ). [ 18 ]FDG was injected 10 min later following the exercise task. Whole-body 3-D PET was performed. Five other male volunteers were studied as a control to compare with the exercise group. The PET image data were analyzed using manually defined regions of interest to quantify the regional metabolic rate of glucose (rMRGlc). Group comparisons were made using analysis of variance, and significant differences (P 18 F]FDG-PET can be used as an index of organ energy metabolism for moderate exercise workloads (70% VO 2max ). The results of this investigation may contribute to sports medicine and rehabilitation science. (author)

SirT1 regulates energy metabolism and response to caloric restriction in mice.

Directory of Open Access Journals (Sweden)

Gino Boily

Full Text Available The yeast sir2 gene and its orthologues in Drosophila and C. elegans have well-established roles in lifespan determination and response to caloric restriction. We have studied mice carrying two null alleles for SirT1, the mammalian orthologue of sir2, and found that these animals inefficiently utilize ingested food. These mice are hypermetabolic, contain inefficient liver mitochondria, and have elevated rates of lipid oxidation. When challenged with a 40% reduction in caloric intake, normal mice maintained their metabolic rate and increased their physical activity while the metabolic rate of SirT1-null mice dropped and their activity did not increase. Moreover, CR did not extend lifespan of SirT1-null mice. Thus, SirT1 is an important regulator of energy metabolism and, like its orthologues from simpler eukaryotes, the SirT1 protein appears to be required for a normal response to caloric restriction.

Constraints on energy intake in fish: the link between diet composition, energy metabolism, and energy intake in rainbow trout.

Directory of Open Access Journals (Sweden)

Subramanian Saravanan

Full Text Available The hypothesis was tested that fish fed to satiation with iso-energetic diets differing in macronutrient composition will have different digestible energy intakes (DEI but similar total heat production. Four iso-energetic diets (2 × 2 factorial design were formulated having a contrast in i the ratio of protein to energy (P/E: high (H(P/E vs. low (L(P/E and ii the type of non-protein energy (NPE source: fat vs. carbohydrate which were iso-energetically exchanged. Triplicate groups (35 fish/tank of rainbow trout were hand-fed each diet twice daily to satiation for 6 weeks under non-limiting water oxygen conditions. Feed intake (FI, DEI (kJ kg(-0.8 d(-1 and growth (g kg(-0.8 d(-1 of trout were affected by the interaction between P/E ratio and NPE source of the diet (P0.05. Our data suggest that the control of DEI in trout might be a function of heat production, which in turn might reflect a physiological limit related with oxidative metabolism.

Republic of Lithuania national energy strategy. Vol. 1: The strategy. Final report

International Nuclear Information System (INIS)

1993-11-01

The aim of the study was to determine the strategic goals needed for modernizing the Lithuanian energy system, to identify the actions which will attain those goals and to advise how the actions may be implemented. Key issues of Lithuania's energy sector are introduced and macro economic scenarios as well as projected energy demand scenarios are explained. Suggestions on energy demand and supply side options are presented and those options are examined in scenarios of possible future energy demand and supply developments. These scenarios differ according to various constrains relating to fuel import sources and prices, export potential, energy efficiency effects and fossils or nuclear/non-nuclear fuel choices. Finally, recommended strategy which is built on the evaluation of the scenarios is summarised.[Data

Republic of Lithuania national energy strategy. Vol. 1: The strategy. Final report

Energy Technology Data Exchange (ETDEWEB)

IC Consult-ERM Energy Limited-COWI Consult-EC-PHARE Programme Collaboration

1993-11-01

The aim of the study was to determine the strategic goals needed for modernizing the Lithuanian energy system, to identify the actions which will attain those goals and to advise how the actions may be implemented. Key issues of Lithuania`s energy sector are introduced and macro economic scenarios as well as projected energy demand scenarios are explained. Suggestions on energy demand and supply side options are presented and those options are examined in scenarios of possible future energy demand and supply developments. These scenarios differ according to various constrains relating to fuel import sources and prices, export potential, energy efficiency effects and fossils or nuclear/non-nuclear fuel choices. Finally, recommended strategy which is built on the evaluation of the scenarios is summarised.[Data].

Main influence factors on the final energy generation cost of a nuclear power plant in comparison with other energy sources

International Nuclear Information System (INIS)

Souza, J.A.M. de; Glardon, C.; Schmidt, R.M.

1981-01-01

The main factors in the construction and in the operation of nuclear power plants that affect the final energy generation cost are presented. The structure of the energy generation cost, of the nuclear fuel cost and the total investment are studied. (E.G.) [pt

Modelling central metabolic fluxes by constraint-based optimization reveals metabolic reprogramming of developing Solanum lycopersicum (tomato) fruit.

Science.gov (United States)

Colombié, Sophie; Nazaret, Christine; Bénard, Camille; Biais, Benoît; Mengin, Virginie; Solé, Marion; Fouillen, Laëtitia; Dieuaide-Noubhani, Martine; Mazat, Jean-Pierre; Beauvoit, Bertrand; Gibon, Yves

2015-01-01

Modelling of metabolic networks is a powerful tool to analyse the behaviour of developing plant organs, including fruits. Guided by our current understanding of heterotrophic metabolism of plant cells, a medium-scale stoichiometric model, including the balance of co-factors and energy, was constructed in order to describe metabolic shifts that occur through the nine sequential stages of Solanum lycopersicum (tomato) fruit development. The measured concentrations of the main biomass components and the accumulated metabolites in the pericarp, determined at each stage, were fitted in order to calculate, by derivation, the corresponding external fluxes. They were used as constraints to solve the model by minimizing the internal fluxes. The distribution of the calculated fluxes of central metabolism were then analysed and compared with known metabolic behaviours. For instance, the partition of the main metabolic pathways (glycolysis, pentose phosphate pathway, etc.) was relevant throughout fruit development. We also predicted a valid import of carbon and nitrogen by the fruit, as well as a consistent CO2 release. Interestingly, the energetic balance indicates that excess ATP is dissipated just before the onset of ripening, supporting the concept of the climacteric crisis. Finally, the apparent contradiction between calculated fluxes with low values compared with measured enzyme capacities suggest a complex reprogramming of the metabolic machinery during fruit development. With a powerful set of experimental data and an accurate definition of the metabolic system, this work provides important insight into the metabolic and physiological requirements of the developing tomato fruits. © 2014 The Authors The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.

Physical activity energy expenditure vs cardiorespiratory fitness level in impaired glucose metabolism

DEFF Research Database (Denmark)

Lidegaard, Lærke P; Hansen, Anne-Louise Smidt; Johansen, Nanna B

2015-01-01

Aim/hypothesis: Little is known about the relative roles of physical activity energy expenditure (PAEE) and cardiorespiratory fitness (CRF) as determinants of glucose regulation. The aim of this study was to examine the associations of PAEE and CRF with markers of glucose metabolism, and to test...... the hypothesis that CRF modifies the association between PAEE and glucose metabolism. Methods: We analysed cross-sectional data from 755 adults from the Danish ADDITION-PRO study. On the basis of OGTT results, participants without known diabetes were classified as having normal glucose tolerance, isolated...... impaired fasting glycaemia (i-IFG), isolated impaired glucose tolerance (i-IGT), combined IFG + IGT or screen-detected diabetes mellitus. Markers of insulin sensitivity and beta cell function were determined. PAEE was measured using a combined heart rate and movement sensor. CRF (maximal oxygen uptake...

Effect of the pattern of food intake on human energy metabolism.

Science.gov (United States)

Verboeket-van de Venne, W P; Westerterp, K R; Kester, A D

1993-07-01

The pattern of food intake can affect the regulation of body weight and lipogenesis. We studied the effect of meal frequency on human energy expenditure (EE) and its components. During 1 week ten male adults (age 25-61 years, body mass index 20.7-30.4 kg/m2) were fed to energy balance at two meals/d (gorging pattern) and during another week at seven meals/d (nibbling pattern). For the first 6 d of each week the food was provided at home, followed by a 36 h stay in a respiration chamber. O2 consumption and CO2 production (and hence EE) were calculated over 24 h. EE in free-living conditions was measured over the 2 weeks with doubly-labelled water (average daily metabolic rate, ADMR). The three major components of ADMR are basal metabolic rate (BMR), diet-induced thermogenesis (DIT) and EE for physical activity (ACT). There was no significant effect of meal frequency on 24 h EE or ADMR. Furthermore, BMR and ACT did not differ between the two patterns. DIT was significantly elevated in the gorging pattern, but this effect was neutralized by correction for the relevant time interval. With the method used for determination of DIT no significant effect of meal frequency on the contribution of DIT to ADMR could be demonstrated.

Energy metabolism after U.V.-irradiation in a sensitive yeast strain

International Nuclear Information System (INIS)

Kiefer, J.

1976-01-01

Stationary-phase cells of an excision-repair deficient diploid yeast (strain 2094) were UV-irradiated at exposures of up to 440 erg mm -2 and then resuspended in fresh medium. Measurements of energy metabolism per cell at periods of up to 6 hours after irradiation showed that cellular respiration was increased for all doses tested from about 3 hours after exposure, whereas fermentation did not start before about 2 hours after irradiation, never significantly exceeded control values and was markedly inhibited by the higher doses. The results suggest that respiration is under nuclear control, since a mutation in one gene is thought to be the only difference between this strain and the wild-type. The D 0 value of about 360 erg mm -2 found for the relative cellular fermentation at 2 hours after irradiation was used to give an estimate of the size of the structural gene involved, of about 3000 nucleotides, or a protein with 1000 amino-acid residues, compatible with the molecular weight of alcohol dehydrogenase. Fermentation can therefore be inhibited in this sensitive strain by lesions in the structural gene of a key enzyme. Since respiration was increased even more in repair-deficient than in repair-proficient strains, it must be assumed that higher energy metabolism is not linked to the repair process, but rather reflects a general disturbance in cellular regulation. (U.K.)

Comparison of Various Indices of Energy Metabolism in Recumbent and Healthy Dairy Cows.

Science.gov (United States)

Guyot, Hugues; Detilleux, Johann; Lebreton, Pascal; Garnier, Catherine; Bonvoisin, Marie; Rollin, Frederic; Sandersen, Charlotte

2017-01-01

Downer cow syndrome (DCS) is often diagnosed in dairy cattle during the early post-partum period. The etiology of this condition is not completely understood, as it can be related to the energetic or electrolyte metabolism, as well as to infectious diseases or to trauma. The aim of this study is to compare energy metabolism and insulin sensitivity indices and various biochemical parameters between recumbent and healthy dairy cows. A prospective study has been undertaken on 361 recumbent and 80 healthy Holstein cows. Plasmatic glucose, insulin, non-esterified fatty acid (NEFA) and β-hydroxybutyrate (BHB) were assayed in all cows in order to calculate the insulin sensitivity indices but also minerals (Calcium, Phosphorous and Magnesium), thyroxin and creatine kinase. Body Condition Scores (BCS) was assessed. Significant differences in NEFA, and the glucose and insulin sensitivity indices ("Homeostasis Model Assessment" HOMA, "Revised Quantitative Insulin Sensitivity Check Index" RQUICKI, RQUICKI-BHB) were observed between healthy and recumbent cows in the early post-parturient period indicating disturbances of glucose and insulin homeostasis in the recumbent cows. In the same manner, mineral concentrations were significantly different between healthy and recumbent cows. Glucose, insulin NEFA, and HOMA, were different between early post-partum downer cows and the DCS-affected cows later in lactation. Results indicate disturbances in energy homeostasis in DCS-affected dairy cows. Further research should determine a prognostic value of the indices in cows suffering from recumbency of metabolic origin.

Comparison of Various Indices of Energy Metabolism in Recumbent and Healthy Dairy Cows.

Directory of Open Access Journals (Sweden)

Hugues Guyot

Full Text Available Downer cow syndrome (DCS is often diagnosed in dairy cattle during the early post-partum period. The etiology of this condition is not completely understood, as it can be related to the energetic or electrolyte metabolism, as well as to infectious diseases or to trauma.The aim of this study is to compare energy metabolism and insulin sensitivity indices and various biochemical parameters between recumbent and healthy dairy cows.A prospective study has been undertaken on 361 recumbent and 80 healthy Holstein cows.Plasmatic glucose, insulin, non-esterified fatty acid (NEFA and β-hydroxybutyrate (BHB were assayed in all cows in order to calculate the insulin sensitivity indices but also minerals (Calcium, Phosphorous and Magnesium, thyroxin and creatine kinase. Body Condition Scores (BCS was assessed.Significant differences in NEFA, and the glucose and insulin sensitivity indices ("Homeostasis Model Assessment" HOMA, "Revised Quantitative Insulin Sensitivity Check Index" RQUICKI, RQUICKI-BHB were observed between healthy and recumbent cows in the early post-parturient period indicating disturbances of glucose and insulin homeostasis in the recumbent cows. In the same manner, mineral concentrations were significantly different between healthy and recumbent cows. Glucose, insulin NEFA, and HOMA, were different between early post-partum downer cows and the DCS-affected cows later in lactation.Results indicate disturbances in energy homeostasis in DCS-affected dairy cows. Further research should determine a prognostic value of the indices in cows suffering from recumbency of metabolic origin.

The relationship between basal metabolic rate and daily energy expenditure in birds and mammals

NARCIS (Netherlands)

Ricklefs, RE; Konarzewski, M; Daan, S

We examined the relationship between daily energy expenditure (DEE) and basal metabolic rate (BMR) in birds and mammals. Two models of the relationship between DEE and BMR were distinguished: a ''shared pathways'' model in which DEE replaces BMR in the active organism and a ''partitioned pathways''

Dynamic changes in energy metabolism upon embryonic stem cell differentiation support developmental toxicant identification

NARCIS (Netherlands)

Dartel, van D.A.M.; Schulpen, S.H.; Theunissen, P.T.; Bunschoten, A.; Piersma, A.H.; Keijer, J.

2014-01-01

Embryonic stem cells (ESC) are widely used to study embryonic development and to identify developmental toxicants. Particularly, the embryonic stem cell test (EST) is well known as in vitro model to identify developmental toxicants. Although it is clear that energy metabolism plays a crucial role in

Glucose stimulates intestinal epithelial crypt proliferation by modulating cellular energy metabolism.

Science.gov (United States)

Zhou, Weinan; Ramachandran, Deepti; Mansouri, Abdelhak; Dailey, Megan J

2018-04-01

The intestinal epithelium plays an essential role in nutrient absorption, hormone release, and barrier function. Maintenance of the epithelium is driven by continuous cell renewal by stem cells located in the intestinal crypts. The amount and type of diet influence this process and result in changes in the size and cellular make-up of the tissue. The mechanism underlying the nutrient-driven changes in proliferation is not known, but may involve a shift in intracellular metabolism that allows for more nutrients to be used to manufacture new cells. We hypothesized that nutrient availability drives changes in cellular energy metabolism of small intestinal epithelial crypts that could contribute to increases in crypt proliferation. We utilized primary small intestinal epithelial crypts from C57BL/6J mice to study (1) the effect of glucose on crypt proliferation and (2) the effect of glucose on crypt metabolism using an extracellular flux analyzer for real-time metabolic measurements. We found that glucose increased both crypt proliferation and glycolysis, and the glycolytic pathway inhibitor 2-deoxy-d-glucose (2-DG) attenuated glucose-induced crypt proliferation. Glucose did not enhance glucose oxidation, but did increase the maximum mitochondrial respiratory capacity, which may contribute to glucose-induced increases in proliferation. Glucose activated Akt/HIF-1α signaling pathway, which might be at least in part responsible for glucose-induced glycolysis and cell proliferation. These results suggest that high glucose availability induces an increase in crypt proliferation by inducing an increase in glycolysis with no change in glucose oxidation. © 2017 Wiley Periodicals, Inc.

The Contribution of Different Components in QiShenYiQi Pills® to Its Potential to Modulate Energy Metabolism in Protection of Ischemic Myocardial Injury

Directory of Open Access Journals (Sweden)

Yuan-Chen Cui

2018-04-01

Full Text Available Ischemic heart diseases remain a challenge for clinicians. QiShenYiQi pills® (QSYQ has been reported to be curative during coronary heart diseases with modulation of energy metabolism as one of the underlying mechanisms. In this study, we detected the effect of QSYQ and its components on rat myocardial structure, mitochondrial respiratory chain complexes activity and energy metabolism, and heart function after 30 min of cardiac ischemia, with focusing on the contribution of each component to its potential to regulate energy metabolism. Results showed that treatment with QSYQ and all its five components protected myocardial structure from damage by ischemia. QSYQ also attenuated release of myocardial cTnI, and restored the production of ATP after cardiac ischemia. AS-IV and Rb1, but not Rg1, R1, and DLA, had similar effect as QSYQ in regulation of energy metabolism. These results indicate that QSYQ may prevent ischemia-induced cardiac injury via regulation of energy metabolism, to which each of its components contributes differently.

Potential hepatic toxicity of buprofezin at sublethal concentrations: ROS-mediated conversion of energy metabolism.

Science.gov (United States)

Ji, Xiaotong; Ku, Tingting; Zhu, Na; Ning, Xia; Wei, Wei; Li, Guangke; Sang, Nan

2016-12-15

Buprofezin is known for its broad-spectrum action and environmental safety. The popularity of buprofezin has raised concerns about its potentially adverse effects on human health and risk to the environment. In this study, we first identified the liver as one of the major organs in which buprofezin accumulated, and we detected a severe oxidative stress response. Next, we demonstrated that sublethal concentrations of buprofezin promoted the conversion of energy metabolism from the aerobic tricarboxylic acid (TCA) cycle and oxidative phosphorylation to anaerobic glycolysis. Importantly, reactive oxygen species (ROS) generation partially accounted for the shunting of the energy metabolism through the buprofezin-mediated inhibition of cytochrome c oxidase activity. ROS directly perturbed the activities of several key TCA cycle enzymes, stimulated glycolysis, and indirectly disturbed the activity of the respiratory chain complex by altering mitochondrial DNA (mtDNA). These findings clarify the potential mechanisms of buprofezin toxicity and provide biomarkers for buprofezin-mediated hepatotoxicity at sublethal concentrations. Copyright © 2016 Elsevier B.V. All rights reserved.

Energy Metabolism and Transfer of {sup 3}H and {sup 14}C in Mammals and Birds - Energy metabolism and transfer of {sup 3}H and {sup 14}C in mammals, birds, and fish

Energy Technology Data Exchange (ETDEWEB)

Melintescu, Anca; Galeriu, Dan [' Horia Hulubei' National Institute for Physics and Nuclear Engineering, Department of Environmental Physics and Life, 30 Reactorului St., POB MG-6, Bucharest-Magurele, RO-077125 (Romania); Beresford, Nicholas A. [NERC Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Av. Bailrigg, Lancaster LA1 4AP (United Kingdom)

2014-07-01

The transfer of {sup 3}H and {sup 14}C in environment needs to be modelled differently than that of other radionuclides released from nuclear facilities because hydrogen and carbon are key components of biological tissues and the carbon and hydrogen life cycles. A detailed understanding of the behaviour of {sup 3}H and {sup 14}C in the food chain is essential because {sup 3}H may be released in large quantities from CANDU (Canadian Deuterium Uranium) reactors and future thermonuclear reactors, and {sup 14}C accumulates in the environment because of its long half-life. In recent years, the authors published both a simple and a complex dynamic metabolic model for {sup 3}H and {sup 14}C transfer to farm and wild animals. The models applications for wild animals were restricted to few examples. There is an increased interest to extend the models for a larger selection of wild animals, birds and fish to support developments such as the International Commission for Radiological Protection (ICRP) environmental protection framework. In this paper we describe activities to expand {sup 3}H and {sup 14}C models to cover a wider range of wildlife. The updated model of the dynamics of tritium transfer in aquatic food chains (AQUATRIT model) developed by the authors was successfully tested for small and large (trout) fish. Wild mammals and birds generally have a lower fat content than domestic species and must adapt to variable environmental conditions. The body mass is an important parameter involved in radionuclide transfer. The environmental temperature, type of animal, and diet must also be considered. The model input parameters for wild mammals are poorly defined because the experimental data are too few and the intraspecific variability is higher than that for farm and laboratory mammals. In the present study, our previously published approach considering the use of energy metabolism and the link between energy and organic matter turnover rate at the whole body and organ

Hepatic diseases related to triglyceride metabolism.

Science.gov (United States)

Aguilera-Méndez, Asdrubal; Álvarez-Delgado, Carolina; Hernández-Godinez, Daniel; Fernandez-Mejia, Cristina

2013-10-01

Triglycerides participate in key metabolic functions such as energy storage, thermal insulation and as deposit for essential and non-essential fatty acids that can be used as precursors for the synthesis of structural and functional phospholipids. The liver is a central organ in the regulation of triglyceride metabolism, and it participates in triglyceride synthesis, export, uptake and oxidation. The metabolic syndrome and associated diseases are among the main concerns of public health worldwide. One of the metabolic syndrome components is impaired triglyceride metabolism. Diseases associated with the metabolic syndrome promote the appearance of hepatic alterations e.g., non-alcoholic steatosis, steatohepatitis, fibrosis, cirrhosis and cancer. In this article, we review the molecular actions involved in impaired triglyceride metabolism and its association with hepatic diseases. We discuss mechanisms that reconcile the chronic inflammation and insulin resistance, and new concepts on the role of intestinal micro-flora permeability and proliferation in fatty liver etiology. We also describe the participation of oxidative stress in the progression of events leading from steatosis to steatohepatitis and fibrosis. Finally, we provide information regarding the mechanisms that link fatty acid accumulation during steatosis with changes in growth factors and cytokines that lead to the development of neoplastic cells. One of the main medical concerns vis-a-vis hepatic diseases is the lack of symptoms at the onset of the illness and, as result, its late diagnosis. The understandings of the molecular mechanisms that underlie hepatic diseases could help design strategies towards establishing markers for their accurate and timely diagnosis.

Commercialization of a high energy neutral beam ion source. Final report

International Nuclear Information System (INIS)

1979-01-01

This final report summarizes the effort and presents the results of a Phase II fabrication effort to build an industrial prototype of the LBL developed high energy neutral beam source. The effort was primarily concentrated on incorporating hard vacuum dielectric seals and a ceramic high voltage accelerator insulator. Several other design changes were incorporated for cost, reliability or life improvements to include: (1) accelerator grid locating dowel pins to aid final alignment, (2) plasma source to accelerator captive fasteners to aid filament replacement during source maintenance, (3) molybdenum cooling tubes on all accelerator grids, (4) additional fasteners in the plasma generator to facilitate hard seals, (5) modified suppressor grid rails and holders to simplify final grid alignment, (6) adjusting screws on exit grid rail holders to simplify final grid alignment, (7) addition of adjusting screws to the grid end pieces to simplify alignment, and (8) addition of accelerator hat shims to allow two different grid positioning locations

Commercialization of a high energy neutral beam ion source. Final report

Energy Technology Data Exchange (ETDEWEB)

1979-12-21

This final report summarizes the effort and presents the results of a Phase II fabrication effort to build an industrial prototype of the LBL developed high energy neutral beam source. The effort was primarily concentrated on incorporating hard vacuum dielectric seals and a ceramic high voltage accelerator insulator. Several other design changes were incorporated for cost, reliability or life improvements to include: (1) accelerator grid locating dowel pins to aid final alignment, (2) plasma source to accelerator captive fasteners to aid filament replacement during source maintenance, (3) molybdenum cooling tubes on all accelerator grids, (4) additional fasteners in the plasma generator to facilitate hard seals, (5) modified suppressor grid rails and holders to simplify final grid alignment, (6) adjusting screws on exit grid rail holders to simplify final grid alignment, (7) addition of adjusting screws to the grid end pieces to simplify alignment, and (8) addition of accelerator hat shims to allow two different grid positioning locations.

Changes in energy metabolism in relation to physical activity due to fermentable carbohydrates in group housed, growing pigs

NARCIS (Netherlands)

Schrama, J.W.; Bakker, G.C.M.

1999-01-01

Fermentable nonstarch polysaccharides (dietary fiber) affect energy retention in group-housed growing pigs by reducing physical activity. This study assessed the effects of fermentation and bulkiness of dietary carbohydrates on physical activity in relation to energy metabolism. Eight clusters of 14

Changes in energy metabolism in relation to physical activity due to fermentable carbohydrates in group-housed growing pigs

NARCIS (Netherlands)

Schrama, J.W.; Bakker, G.C.M.

1999-01-01

Fermentable nonstarch polysaccharides (dietary fiber) affect energy retention in group-housed growing pigs by reducing physical activity. This study assessed the effects of fermentation and bulkiness of dietary carbohydrates on physical activity in relation to energy metabolism. Eight clusters of 14

Mineral absorption and excretion as affected by microbial phytase and their effect on energy metabolism in young piglets

NARCIS (Netherlands)

Kies, A.K.; Gerrits, W.J.J.; Schrama, J.W.; Heetkamp, M.J.W.; Linden, van der K.L.; Zandstra, T.; Verstegen, M.W.A.

2005-01-01

Positive effects of dietary phytase supplementation on pig performance are observed not only when phosphorus is limiting. Improved energy utilization might be one explanation. Using indirect calorimetry, phytase-induced changes in energy metabolism were evaluated in young piglets with adequate

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

DEFF Research Database (Denmark)

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....

Biosynthesis and metabolic fate of phenylalanine in conifers

Directory of Open Access Journals (Sweden)

María Belén Pascual

2016-07-01

Full Text Available The amino acid phenylalanine (Phe is a critical metabolic node that plays an essential role in the interconnection between primary and secondary metabolism in plants. Phe is used as a protein building block but it is also as a precursor for numerous plant compounds that are crucial for plant reproduction, growth, development and defense against different types of stresses. The metabolism of Phe plays a central role in the channeling of carbon from photosynthesis to the biosynthesis of phenylpropanoids. The study of this metabolic pathway is particularly relevant in trees, which divert large amounts of carbon into the biosynthesis of Phe-derived compounds, particularly lignin, an important constituent of wood. The trunks of trees are metabolic sinks that consume a considerable percentage of carbon and energy from photosynthesis, and carbon is finally immobilized in wood. This paper reviews recent advances in the biosynthesis and metabolic utilization of Phe in conifer trees. Two alternative routes have been identified: the ancient phenylpyruvate pathway that is present in microorganisms, and the arogenate pathway that possibly evolved later during plant evolution. Additionally, an efficient nitrogen recycling mechanism is required to maintain sustained growth during xylem formation. The relevance of phenylalanine metabolic pathways in wood formation, the biotic interactions and ultraviolet protection is discussed. The genetic manipulation and transcriptional regulation of the pathways are also outlined.

Biosynthesis and Metabolic Fate of Phenylalanine in Conifers.

Science.gov (United States)

Pascual, María B; El-Azaz, Jorge; de la Torre, Fernando N; Cañas, Rafael A; Avila, Concepción; Cánovas, Francisco M

2016-01-01

The amino acid phenylalanine (Phe) is a critical metabolic node that plays an essential role in the interconnection between primary and secondary metabolism in plants. Phe is used as a protein building block but it is also as a precursor for numerous plant compounds that are crucial for plant reproduction, growth, development, and defense against different types of stresses. The metabolism of Phe plays a central role in the channeling of carbon from photosynthesis to the biosynthesis of phenylpropanoids. The study of this metabolic pathway is particularly relevant in trees, which divert large amounts of carbon into the biosynthesis of Phe-derived compounds, particularly lignin, an important constituent of wood. The trunks of trees are metabolic sinks that consume a considerable percentage of carbon and energy from photosynthesis, and carbon is finally immobilized in wood. This paper reviews recent advances in the biosynthesis and metabolic utilization of Phe in conifer trees. Two alternative routes have been identified: the ancient phenylpyruvate pathway that is present in microorganisms, and the arogenate pathway that possibly evolved later during plant evolution. Additionally, an efficient nitrogen recycling mechanism is required to maintain sustained growth during xylem formation. The relevance of phenylalanine metabolic pathways in wood formation, the biotic interactions, and ultraviolet protection is discussed. The genetic manipulation and transcriptional regulation of the pathways are also outlined.

Effects of dietary fermentable carbohydrates on energy metabolism in group-housed sows.

Science.gov (United States)

Rijnen, M M; Verstegen, M W; Heetkamp, M J; Haaksma, J; Schrama, J W

2001-01-01

The effect of dietary nonstarch polysaccharide (NSP) content on the metabolic rate in group-housed sows was studied. Twelve groups of six nonpregnant sows were each fed one of four experimental diets similar in composition except for the starch and NSP content. Exchanging sugar beet pulp silage (SBPS) for tapioca created the difference in starch and NSP ratio in the diet. On a DM basis, diets contained 0, 10, 20, or 30% SBPS. Sows were group-housed and fed at 1.30 times the assumed maintenance energy requirements. Nitrogen and energy balances were measured per group during a 7-d experimental period, which was preceded by a 33-d adaptation period. Both digestibility and metabolizability of energy decreased with increasing dietary SBPS content (P 0.1). Based on energy retention data and apparent fecal digestibilities of crude protein, crude fat, starch, and NSP, the estimated net energy value of fermented NSP was 13.4 kJ/g. The present study shows that group-housed sows are capable of using energy from fermented NSP (i.e., NSP from SBPS) as efficiently as energy from digested starch (i.e., starch from tapioca).

"Type Ia Supernovae: Tools for Studying Dark Energy" Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Woosley, Stan [Lick Observatory, San Jose, CA (United States); Kasen, Dan [Univ. of California, Berkeley, CA (United States)

2017-05-10

Final technical report for project "Type Ia Supernovae: Tools for the Study of Dark Energy" awarded jointly to scientists at the University of California, Santa Cruz and Berkeley, for computer modeling, theory and data analysis relevant to the use of Type Ia supernovae as standard candles for cosmology.

Changes in energy metabolism in response to 48 h of overfeeding and fasting in Caucasians and Pima Indians

DEFF Research Database (Denmark)

Weyer, C; Vozarova, B; Ravussin, E

2001-01-01

Differences in the metabolic response to overfeeding and starvation may confer susceptibility or resistance to obesity in humans. To further examine this hypothesis, we assessed the changes in 24 h energy metabolism in response to short-term overfeeding and fasting in Caucasians (C) and Pima...... Indians (I), a population with a very high propensity for obesity....

Physiological response to extreme fasting in subantarctic fur seal (Arctocephalus tropicalis) pups: metabolic rates, energy reserve utilization, and water fluxes.

Science.gov (United States)

Verrier, Delphine; Groscolas, René; Guinet, Christophe; Arnould, John P Y

2009-11-01

Surviving prolonged fasting requires various metabolic adaptations, such as energy and protein sparing, notably when animals are simultaneously engaged in energy-demanding processes such as growth. Due to the intermittent pattern of maternal attendance, subantarctic fur seal pups have to repeatedly endure exceptionally long fasting episodes throughout the 10-mo rearing period while preparing for nutritional independence. Their metabolic responses to natural prolonged fasting (33.4 +/- 3.3 days) were investigated at 7 mo of age. Within 4-6 fasting days, pups shifted into a stage of metabolic economy characterized by a minimal rate of body mass loss (0.7%/day) and decreased resting metabolic rate (5.9 +/- 0.1 ml O(2)xkg(-1)xday(-1)) that was only 10% above the level predicted for adult terrestrial mammals. Field metabolic rate (289 +/- 10 kJxkg(-1)xday(-1)) and water influx (7.9 +/- 0.9 mlxkg(-1)xday(-1)) were also among the lowest reported for any young otariid, suggesting minimized energy allocation to behavioral activity and thermoregulation. Furthermore, lean tissue degradation was dramatically reduced. High initial adiposity (>48%) and predominant reliance on lipid catabolism likely contributed to the exceptional degree of protein sparing attained. Blood chemistry supported these findings and suggested utilization of alternative fuels, such as beta-hydroxybutyrate and de novo synthesized glucose from fat-released glycerol. Regardless of sex and body condition, pups tended to adopt a convergent strategy of extreme energy and lean body mass conservation that appears highly adaptive for it allows some tissue growth during the repeated episodes of prolonged fasting they experience throughout their development.

Colonic infusions of short-chain fatty acid mixtures promote energy metabolism in overweight/obese men

DEFF Research Database (Denmark)

Canfora, Emanuel E; van der Beek, Christina M; Jocken, Johan W E

2017-01-01

Short-chain fatty acids (SCFA), formed by microbial fermentation, are believed to be involved in the aetiology of obesity and diabetes. This study investigated the effects of colonic administration of physiologically relevant SCFA mixtures on human substrate and energy metabolism...

Carbon and energy metabolism of atp mutants of Escherichia coli

DEFF Research Database (Denmark)

Jensen, Peter Ruhdal; Michelsen, Ole

1992-01-01

strain is not able to utilize the resulting proton motive force for ATP synthesis. Indeed, the ratio of ATP concentration to ADP concentration was decreased from 19 in the wild type to 7 in the atp mutant, and the membrane potential of the atp deletion strain was increased by 20%, confirming......The membrane-bound H+-ATPase plays a key role in free-energy transduction of biological systems. We report how the carbon and energy metabolism of Escherichia coli changes in response to deletion of the atp operon that encodes this enzyme. Compared with the isogenic wild-type strain, the growth...... rate and growth yield were decreased less than expected for a shift from oxidative phosphorylation to glycolysis alone as a source of ATP. Moreover, the respiration rate of a atp deletion strain was increased by 40% compared with the wild-type strain. This result is surprising, since the atp deletion...

Drug discovery strategies in the field of tumor energy metabolism: Limitations by metabolic flexibility and metabolic resistance to chemotherapy.

Science.gov (United States)

Amoedo, N D; Obre, E; Rossignol, R

2017-08-01

The search for new drugs capable of blocking the metabolic vulnerabilities of human tumors has now entered the clinical evaluation stage, but several projects already failed in phase I or phase II. In particular, very promising in vitro studies could not be translated in vivo at preclinical stage and beyond. This was the case for most glycolysis inhibitors that demonstrated systemic toxicity. A more recent example is the inhibition of glutamine catabolism in lung adenocarcinoma that failed in vivo despite a strong addiction of several cancer cell lines to glutamine in vitro. Such contradictory findings raised several questions concerning the optimization of drug discovery strategies in the field of cancer metabolism. For instance, the cell culture models in 2D or 3D might already show strong limitations to mimic the tumor micro- and macro-environment. The microenvironment of tumors is composed of cancer cells of variegated metabolic profiles, supporting local metabolic exchanges and symbiosis, but also of immune cells and stroma that further interact with and reshape cancer cell metabolism. The macroenvironment includes the different tissues of the organism, capable of exchanging signals and fueling the tumor 'a distance'. Moreover, most metabolic targets were identified from their increased expression in tumor transcriptomic studies, or from targeted analyses looking at the metabolic impact of particular oncogenes or tumor suppressors on selected metabolic pathways. Still, very few targets were identified from in vivo analyses of tumor metabolism in patients because such studies are difficult and adequate imaging methods are only currently being developed for that purpose. For instance, perfusion of patients with [ 13 C]-glucose allows deciphering the metabolomics of tumors and opens a new area in the search for effective targets. Metabolic imaging with positron emission tomography and other techniques that do not involve [ 13 C] can also be used to evaluate tumor

A Plant Bacterial Pathogen Manipulates Its Insect Vector's Energy Metabolism

Science.gov (United States)

Hijaz, Faraj; Ebert, Timothy A.; Rogers, Michael E.

2016-01-01

ABSTRACT Insect-transmitted plant-pathogenic bacteria may alter their vectors' fitness, survival, behavior, and metabolism. Because these pathogens interact with their vectors on the cellular and organismal levels, potential changes at the biochemical level might occur. “Candidatus Liberibacter asiaticus” (CLas) is transmitted in a persistent, circulative, and propagative manner. The genome of CLas revealed the presence of an ATP translocase that mediates the uptake of ATP and other nucleotides from medium to achieve its biological processes, such as growth and multiplication. Here, we showed that the levels of ATP and many other nucleotides were significantly higher in CLas-infected than healthy psyllids. Gene expression analysis showed upregulation for ATP synthase subunits, while ATPase enzyme activity showed a decrease in ATPase activity. These results indicated that CLas stimulated Diaphorina citri to produce more ATP and many other energetic nucleotides, while it may inhibit their consumption by the insect. As a result of ATP accumulation, the adenylated energy charge (AEC) increased and the AMP/ATP and ADP/ATP ratios decreased in CLas-infected D. citri psyllids. Survival analysis confirmed a shorter life span for CLas-infected D. citri psyllids. In addition, electropenetrography showed a significant reduction in total nonprobing time, salivation time, and time from the last E2 (phloem ingestion) to the end of recording, indicating that CLas-infected psyllids were at a higher hunger level and they tended to forage more often. This increased feeding activity reflects the CLas-induced energetic stress. In conclusion, CLas alters the energy metabolism of its psyllid vector, D. citri, in order to secure its need for energetic nucleotides. IMPORTANCE Insect transmission of plant-pathogenic bacteria involves propagation and circulation of the bacteria within their vectors. The transmission process is complex and requires specific interactions at the molecular

Adaptations in the energy metabolism of parasites

NARCIS (Netherlands)

van Grinsven, K.W.A.|info:eu-repo/dai/nl/304833436

2009-01-01

For this thesis fundamental research was performed on the metabolic adaptations found in parasites. Studying the adaptations in parasite metabolisms leads to a better understanding of parasite bioenergetics and can also result in the identification of new anti-parasitic drug targets. We focussed on

Brazilian energy balance 2013 - calendar year 2012: final report

International Nuclear Information System (INIS)

2013-01-01

The BEB is divided into eight chapters and ten annexes, whose contents are as follow: Chapter 1- Energy analysis and aggregated data- presents energy highlights per source in 2012 and analyses the evolution of the domestic energy supply and its relationship with economic growth in 2012; Chapter 2- Energy supply and demand by source- has the accountancy, per primary and secondary energy sources, of the production, import, export, variation of stocks, losses, adjustments, disaggregated total per socioeconomic sector in the country; Chapter 3- Energy consumption by sector- presents the final energy consumption classified by primary and secondary source for each sector of the economy; Chapter 4- Energy imports and exports- presents the evolution of the data on the import and export of energy and the dependence on external energy; Chapter 5- Balance of transformation centers- presents the energy balances for the energy transformation centers including their losses; Chapter 6- Energy resources and reserves- has the basic concepts use in the survey of resources and reserves of primary energy sources; Chapter 7- Energy and socioeconomics- contains a comparison of energy, economic and population parameters, specific consumption, energy intensities, average prices and spending on petroleum imports; Chapter 8- State energy data- presents energy data for the states by Federal Unit, main energy source production, energy installations, reserves and hydraulic potential; Relating to annexes the current structure is presented bellow: Annex 1- Installed capacity- shows the installed capacity of electricity generation, the installed capacity of Itaipu hydro plant and the installed capacity for oil refining; Annex 2- Self-production of electricity- presents disaggregated data of self-production, considering sources and sectors. Annex 3- World energy data- presents the main indicators for the production, import, export and consumption per energy source and region; Annex 4- Useful

Brazilian energy balance 2012 - calendar year 2011: final report

International Nuclear Information System (INIS)

2012-01-01

The BEB is divided into eight chapters and ten annexes, whose contents are as follow: Chapter 1- energy analysis and aggregated data- presents energy highlights per source in 2012 and analyses the evolution of the domestic energy supply and its relationship with economic growth in 2011; Chapter 2 - Energy supply and demand by source- has the accountancy, per primary and secondary energy sources, of the production, import, export, variation of stocks, losses, adjustments, disaggregated total per socioeconomic sector in the country; Chapter 3 - Energy consumption by sector- presents the final energy consumption classified by primary and secondary source for each sector of the economy; Chapter 4 - Energy imports and exports- presents the evolution of the data on the import and export of energy and the dependence on external energy; Chapter 5 - Balance of transformation centers - presents the energy balances for the energy transformation centers including their losses; Chapter 6 - Energy resources and reserves- has the basic concepts use in the survey of resources and reserves of primary energy sources; Chapter 7- Energy and socioeconomics - contains a comparison of energy, economic and population parameters, specific consumption, energy intensities, average prices and spending on petroleum imports; Chapter 8- State energy data- presents energy data for the states by Federal Unit, main energy source production, energy installations, reserves and hydraulic potential; Relating to annexes the current structure is presented bellow: Annex 1- Installed capacity- shows the installed capacity of electricity generation, the installed capacity of Itaipu hydro plant and the installed capacity for oil refining.; Annex 2- Self-production of electricity- presents disaggregated data of self-production, considering sources and sectors. Annex 3- World energy data- presents the main indicators for the production, import, export and consumption per energy source and region; Annex 4

Brazilian energy balance 2014 - calendar year 2013: final report

International Nuclear Information System (INIS)

2014-01-01

The BEB is divided into eight chapters and ten annexes, whose contents are as follow: Chapter 1- Energy analysis and aggregated data- presents energy highlights per source in 2012 and analyses the evolution of the domestic energy supply and its relationship with economic growth in 2013; Chapter 2- Energy supply and demand by source- has the accountancy, per primary and secondary energy sources, of the production, import, export, variation of stocks, losses, adjustments, disaggregated total per socioeconomic sector in the country; Chapter 3- Energy consumption by sector- presents the final energy consumption classified by primary and secondary source for each sector of the economy; Chapter 4- Energy imports and exports- presents the evolution of the data on the import and export of energy and the dependence on external energy; Chapter 5- Balance of transformation centers- presents the energy balances for the energy transformation centers including their losses; Chapter 6- Energy resources and reserves- has the basic concepts use in the survey of resources and reserves of primary energy sources; Chapter 7- Energy and socioeconomics- contains a comparison of energy, economic and population parameters, specific consumption, energy intensities, average prices and spending on petroleum imports; Chapter 8- State energy data- presents energy data for the states by Federal Unit, main energy source production, energy installations, reserves and hydraulic potential; Relating to annexes the current structure is presented bellow: Annex 1- Installed capacity- shows the installed capacity of electricity generation, the installed capacity of Itaipu hydro plant and the installed capacity for oil refining.; Annex 2- Self-production of electricity- presents disaggregated data of self-production, considering sources and sectors. Annex 3- World energy data- presents the main indicators for the production, import, export and consumption per energy source and region; Annex 4- Useful

Dissolve energy obesity by energy diet

Energy Technology Data Exchange (ETDEWEB)

Kim, Jung Heum [Sunmoon University, Asan (Korea)

2000-07-01

Every organism takes needed materials or energy from outside and excretes unessential things to outside. This is called a metabolism or energy metabolism. Calculating the amount of energy consumed by human in the world by converting to the amount of metabolism of an animal to survive, the weight of a human being is corresponding to an animal with a weigh of 40 ton. Human beings can find a solution to dissolve energy obesity or can maintain a massive status by finding a new energy source in the universe.

The role of acyl-CoA:diacylglycerol acyltransferase (DGAT) in energy metabolism.

Science.gov (United States)

Yu, Yi-Hao; Ginsberg, Henry N

2004-01-01

Acyl-CoA:diacylglycerol acyltransferase (DGAT, EC2.3.1.20), a key enzyme in triglyceride (TG) biosynthesis, not only participates in lipid metabolism but also influences metabolic pathways of other fuel molecules. Changes in the expression and/or activity levels of DGAT may lead to changes in systemic insulin sensitivity and energy homeostasis. The synthetic role of DGAT in adipose tissue, the liver, and the intestine, sites where endogenous levels of DGAT activity and TG synthesis are high, is relatively clear. Less clear is whether DGAT plays a mediating or preventive role in the development of ectopic lipotoxicity in tissues such as muscle and the pancreas, when their supply of free fatty acids (FFAs) exceeds their needs. Future studies with tissue-specific overexpression and/or knockout in these animal models would be expected to shed additional light on these issues.

Associations of fatty acids in cerebrospinal fluid with peripheral glucose concentrations and energy metabolism.

Directory of Open Access Journals (Sweden)

Reiner Jumpertz

Full Text Available Rodent experiments have emphasized a role of central fatty acid (FA species, such as oleic acid, in regulating peripheral glucose and energy metabolism. Thus, we hypothesized that central FAs are related to peripheral glucose regulation and energy expenditure in humans. To test this we measured FA species profiles in cerebrospinal fluid (CSF and plasma of 32 individuals who stayed in our clinical inpatient unit for 6 days. Body composition was measured by dual energy X-ray absorptiometry and glucose regulation by an oral glucose test (OGTT followed by measurements of 24 hour (24EE and sleep energy expenditure (SLEEP as well as respiratory quotient (RQ in a respiratory chamber. CSF was obtained via lumbar punctures; FA concentrations were measured by liquid chromatography/mass spectrometry. As expected, FA concentrations were higher in plasma compared to CSF. Individuals with high concentrations of CSF very-long-chain saturated FAs had lower rates of SLEEP. In the plasma moderate associations of these FAs with higher 24EE were observed. Moreover, CSF monounsaturated long-chain FA (palmitoleic and oleic acid concentrations were associated with lower RQs and lower glucose area under the curve during the OGTT. Thus, FAs in the CSF strongly correlated with peripheral metabolic traits. These physiological parameters were most specific to long-chain monounsaturated (C16:1, C18:1 and very-long-chain saturated (C24:0, C26:0 FAs.Together with previous animal experiments these initial cross-sectional human data indicate that central FA species are linked to peripheral glucose and energy homeostasis.

N-3 fatty acids, neuronal activity and energy metabolism in the brain

Directory of Open Access Journals (Sweden)

Harbeby Emilie

2012-07-01

Full Text Available The content of docosahexaenoic acid (DHA in brain membranes is of crucial importance for the optimum development of brain functions. A lack of DHA accretion in the brain is accompanied by deficits in learning behavior linked to impairments in neurotransmission processes, which might result from alteration of brain fuel supply and hence energy metabolism. Experimental data we published support the hypothesis that n-3 fatty acids may modulate brain glucose utilization and metabolism. Indeed rats made deficient in DHA by severe depletion of total n-3 fatty acid intake have 1 a lower brain glucose utilization, 2 a decrease of the glucose transporter protein content GLUT1 both in endothelial cells and in astrocytes, 3 a repression of GLUT1 gene expression in basal state as well as upon neuronal activation. This could be due to the specific action of DHA on the regulation of GLUT1 expression since rat brain endothelial cells cultured with physiological doses of DHA had an increased GLUT1 protein content and glucose transport when compared to non-supplemented cells. These experimental data highlight the impact of n-3 fatty acids on the use of brain glucose, thereby constituting a key factor in the control of synaptic activity. This emerging role suggests that dietary intake of n-3 fatty acids can help to reduce the cognitive deficits in the elderly and possibly symptomatic cerebral metabolic alterations in Alzheimer disease by promoting brain glucose metabolism.

Gustatory perception and fat body energy metabolism are jointly affected by vitellogenin and juvenile hormone in honey bees.

Science.gov (United States)

Wang, Ying; Brent, Colin S; Fennern, Erin; Amdam, Gro V

2012-06-01

Honey bees (Apis mellifera) provide a system for studying social and food-related behavior. A caste of workers performs age-related tasks: young bees (nurses) usually feed the brood and other adult bees inside the nest, while older bees (foragers) forage outside for pollen, a protein/lipid source, or nectar, a carbohydrate source. The workers' transition from nursing to foraging and their foraging preferences correlate with differences in gustatory perception, metabolic gene expression, and endocrine physiology including the endocrine factors vitellogenin (Vg) and juvenile hormone (JH). However, the understanding of connections among social behavior, energy metabolism, and endocrine factors is incomplete. We used RNA interference (RNAi) to perturb the gene network of Vg and JH to learn more about these connections through effects on gustation, gene transcripts, and physiology. The RNAi perturbation was achieved by single and double knockdown of the genes ultraspiracle (usp) and vg, which encode a putative JH receptor and Vg, respectively. The double knockdown enhanced gustatory perception and elevated hemolymph glucose, trehalose, and JH. We also observed transcriptional responses in insulin like peptide 1 (ilp1), the adipokinetic hormone receptor (AKHR), and cGMP-dependent protein kinase (PKG, or "foraging gene" Amfor). Our study demonstrates that the Vg-JH regulatory module controls changes in carbohydrate metabolism, but not lipid metabolism, when worker bees shift from nursing to foraging. The module is also placed upstream of ilp1, AKHR, and PKG for the first time. As insulin, adipokinetic hormone (AKH), and PKG pathways influence metabolism and gustation in many animals, we propose that honey bees have conserved pathways in carbohydrate metabolism and conserved connections between energy metabolism and gustatory perception. Thus, perhaps the bee can make general contributions to the understanding of food-related behavior and metabolic disorders.

Gustatory perception and fat body energy metabolism are jointly affected by vitellogenin and juvenile hormone in honey bees.

Directory of Open Access Journals (Sweden)

Ying Wang

2012-06-01

Full Text Available Honey bees (Apis mellifera provide a system for studying social and food-related behavior. A caste of workers performs age-related tasks: young bees (nurses usually feed the brood and other adult bees inside the nest, while older bees (foragers forage outside for pollen, a protein/lipid source, or nectar, a carbohydrate source. The workers' transition from nursing to foraging and their foraging preferences correlate with differences in gustatory perception, metabolic gene expression, and endocrine physiology including the endocrine factors vitellogenin (Vg and juvenile hormone (JH. However, the understanding of connections among social behavior, energy metabolism, and endocrine factors is incomplete. We used RNA interference (RNAi to perturb the gene network of Vg and JH to learn more about these connections through effects on gustation, gene transcripts, and physiology. The RNAi perturbation was achieved by single and double knockdown of the genes ultraspiracle (usp and vg, which encode a putative JH receptor and Vg, respectively. The double knockdown enhanced gustatory perception and elevated hemolymph glucose, trehalose, and JH. We also observed transcriptional responses in insulin like peptide 1 (ilp1, the adipokinetic hormone receptor (AKHR, and cGMP-dependent protein kinase (PKG, or "foraging gene" Amfor. Our study demonstrates that the Vg-JH regulatory module controls changes in carbohydrate metabolism, but not lipid metabolism, when worker bees shift from nursing to foraging. The module is also placed upstream of ilp1, AKHR, and PKG for the first time. As insulin, adipokinetic hormone (AKH, and PKG pathways influence metabolism and gustation in many animals, we propose that honey bees have conserved pathways in carbohydrate metabolism and conserved connections between energy metabolism and gustatory perception. Thus, perhaps the bee can make general contributions to the understanding of food-related behavior and metabolic disorders.

The Role of Exercise – Rehabilitation on Energy Cost and Metabolic Efficiency in Dipelegic Spastic Cerebral Palsy Children

Directory of Open Access Journals (Sweden)

M. Izadi

2005-07-01

Full Text Available Introduction & Objective: The aim of this study was to compare the resting energy expenditure and metabolic efficiency before and after of aerobic exercise in spastic cerebral palsy children (mean age of 11 years and also to compare with those of normal children. Materials & Methods : Fifteen dipelegia spastic cerebral palsy children (experimental group participated in exercise–rehabilitation program by voluntarily and the peers eighteen able body children(control group were selected randomly. The experimental group(cp performed rehabilitation program for 3 months,3 session in week with work intensity(%HRR=462.5equal to144bpm of heart rate. The values were measured on tantory cycle ergometer according to Macmaster protocol.Results: Rest and exercise heart rate and exercise intensity(%HRR in patients decreased after rehabilitation program(P<0.05. The resting energy expenditure was similar in cp and normal groups. The rate of oxygen cost of patients decreased in post test(P<0.05 that showed increasing in metabolic efficiency.Conclusion: cerebral palsy children have greater exercise energy cost and lower cardiovascular fitness than normal children and exercise–rehabilitation leads to enhance of metabolic efficiency in this patients that is remarkable from clinical perception.

Energy metabolism and biotransformation as endpoints to pre-screen hepatotoxicity using a liver spheroid model

International Nuclear Information System (INIS)

Xu Jinsheng; Purcell, Wendy M.

2006-01-01

The current study investigated liver spheroid culture as an in vitro model to evaluate the endpoints relevant to the status of energy metabolism and biotransformation after exposure to test toxicants. Mature rat liver spheroids were exposed to diclofenac, galactosamine, isoniazid, paracetamol, m-dinitrobenzene (m-DNB) and 3-nitroaniline (3-NA) for 24 h. Pyruvate uptake, galactose biotransformation, lactate release and glucose secretion were evaluated after exposure. The results showed that pyruvate uptake and lactate release by mature liver spheroids in culture were maintained at a relatively stable level. These endpoints, together with glucose secretion and galactose biotransformation, were related to and could reflect the status of energy metabolism and biotransformation in hepatocytes. After exposure, all of the test agents significantly reduced glucose secretion, which was shown to be the most sensitive endpoint of those evaluated. Diclofenac, isoniazid, paracetamol and galactosamine reduced lactate release (P < 0.01), but m-DNB increased lactate release (P < 0.01). Diclofenac, isoniazid and paracetamol also reduced pyruvate uptake (P < 0.01), while galactosamine had little discernible effect. Diclofenac, galactosamine, paracetamol and m-DNB also reduced galactose biotransformation (P < 0.01), by contrast, isoniazid did not. The metabolite of m-DNB, 3-NA, which served as a negative control, did not cause significant changes in lactate release, pyruvate uptake or galactose biotransformation. It is concluded that pyruvate uptake, galactose biotransformation, lactate release and glucose secretion can be used as endpoints for evaluating the status of energy metabolism and biotransformation after exposure to test agents using the liver spheroid model to pre-screen hepatotoxicity

Final stage of high energy hadron-nucleus nuclear collision reactions

International Nuclear Information System (INIS)

Strugal'ski, Z.; Jedrzejec, H.; Strugalska-Gola, E.; Mulas, E.

1996-01-01

The final or 'slow' stage of the hadron-nucleus collision reactions at high energy is considered on the basis of the collision mechanism prompted experimentally. The transmutation process of the damaged target nucleus into nucleons and stable nuclear fragments is discussed. Relations between intensities or multiplicities n p of the emitted fast protons and the mean intensities or multiplicities b > of the evaporated nucleons and nuclear fragments are presented. 14 refs

Effects of energy restriction on acute adrenoceptor and metabolic responses to exercise in obese subjects

NARCIS (Netherlands)

Kempen, K.P.G.; Saris, W.H.M.; Senden, J.M.G.; Menheere, P.P.C.A.; Blaak, E.E.; van Baak, M.A.

1994-01-01

Effects of energy restriction on acute adrenoceptor and metabolic responses to exercise in obese subjects. Kempen KP, Saris WH, Senden JM, Menheere PP, Blaak EE, van Baak MA. Department of Human Biology, University of Limburg, Maastricht, The Netherlands. This study was intended to investigate the

Metabolic Adaptation to Muscle Ischemia

Science.gov (United States)

Cabrera, Marco E.; Coon, Jennifer E.; Kalhan, Satish C.; Radhakrishnan, Krishnan; Saidel, Gerald M.; Stanley, William C.

2000-01-01

Although all tissues in the body can adapt to varying physiological/pathological conditions, muscle is the most adaptable. To understand the significance of cellular events and their role in controlling metabolic adaptations in complex physiological systems, it is necessary to link cellular and system levels by means of mechanistic computational models. The main objective of this work is to improve understanding of the regulation of energy metabolism during skeletal/cardiac muscle ischemia by combining in vivo experiments and quantitative models of metabolism. Our main focus is to investigate factors affecting lactate metabolism (e.g., NADH/NAD) and the inter-regulation between carbohydrate and fatty acid metabolism during a reduction in regional blood flow. A mechanistic mathematical model of energy metabolism has been developed to link cellular metabolic processes and their control mechanisms to tissue (skeletal muscle) and organ (heart) physiological responses. We applied this model to simulate the relationship between tissue oxygenation, redox state, and lactate metabolism in skeletal muscle. The model was validated using human data from published occlusion studies. Currently, we are investigating the difference in the responses to sudden vs. gradual onset ischemia in swine by combining in vivo experimental studies with computational models of myocardial energy metabolism during normal and ischemic conditions.

Reaction engineering analysis of the autotrophic energy metabolism of Clostridium aceticum.

Science.gov (United States)

Mayer, Alexander; Weuster-Botz, Dirk

2017-12-01

Acetogenesis with CO2:H2 or CO via the reductive acetyl-CoA pathway does not provide any net ATP formation in homoacetogenic bacteria. Autotrophic energy conservation is coupled to the generation of chemiosmotic H+ or Na+ gradients across the cytoplasm membrane using either a ferredoxin:NAD+ oxidoreductase (Rnf), a ferredoxin:H+ oxidoreductase (Ech) or substrate-level phosphorylation via cytochromes. The first isolated acetogenic bacterium Clostridium aceticum shows both cytochromes and Rnf complex, putting it into an outstanding position. Autotrophic batch processes with continuous gas supply were performed in fully controlled stirred-tank bioreactors to elucidate energy metabolism of C. aceticum. Varying the initial Na+ concentration in the medium showed sodium-dependent growth of C. aceticum with a growth optimum between 60 and 90 mM Na+. The addition of the Na+-selective ionophore ETH2120 or the protonophore CCCP or the H+/cation-antiporter monensin revealed that an H+ gradient is used as primary energy conservation mechanism, which strengthens the exceptional position of C. aceticum as acetogenic bacterium showing an H+-dependent energy conservation mechanism as well as Na+-dependent growth. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Fat and carbohydrate metabolism during submaximal exercise in children.

Science.gov (United States)

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

Brazilian energy balance 2015: year 2014 - final report; Balanco energetico nacional 2015: ano base 2014 - relatorio final

Energy Technology Data Exchange (ETDEWEB)

NONE

2015-07-01

The Balance (BEB) contains the accounting relative to energy supply and consumption, as well the conversion processes and foreign trade. It presents in a single document the historical series of these operations and information about reserves, installed capacities and Federal States data. The BEB is divided into eight chapters and ten annexes, whose contents are as follow. Chapters' content can be described as follows: Chapter 1 - Energy Analysis and Aggregated Data - presents energy highlights per source in 2014 and analyses the evolution of the domestic energy supply and its relationship with economic growth. Chapter 2 - Energy Supply and Demand by Source - has the accountancy, per primary and secondary energy sources, of the production, import, export, variation of stocks, losses, adjustments, disaggregated total per socioeconomic sector in the country. Chapter 3 - Energy Consumption by Sector - presents the final energy consumption classified by primary and secondary source for each sector of the economy. Chapter 4 - Energy Imports and Exports - presents the evolution of the data on the import and export of energy and the dependence on external energy. Chapter 5 - Balance of Transformation Centers - presents the energy balances for the energy transformation centers including their losses. Chapter 6 - Energy Resources and Reserves - has the basic concepts use in the survey of resources and reserves of primary energy sources. Chapter 7 - Energy and Socio economics - contains a comparison of energy, economic and population parameters, specific consumption, energy intensities, average prices and spending on petroleum imports. Chapter 8 - State Energy Data - presents energy data for the states by Federal Unit, main energy source production, energy installations, reserves and hydraulic potential. Relating to annexes the current structure is presented bellow: Annex I - Installed Capacity - shows the installed capacity of electricity generation, the installed

Impact of Orexin-A Treatment on Food Intake, Energy Metabolism and Body Weight in Mice.

Directory of Open Access Journals (Sweden)

Anne Blais

Full Text Available Orexin-A and -B are hypothalamic neuropeptides of 33 and 28-amino acids, which regulate many homeostatic systems including sleep/wakefulness states, energy balance, energy homeostasis, reward seeking and drug addiction. Orexin-A treatment was also shown to reduce tumor development in xenografted nude mice and is thus a potential treatment for carcinogenesis. The aim of this work was to explore in healthy mice the consequences on energy expenditure components of an orexin-A treatment at a dose previously shown to be efficient to reduce tumor development. Physiological approaches were used to evaluate the effect of orexin-A on food intake pattern, energy metabolism body weight and body adiposity. Modulation of the expression of brain neuropeptides and receptors including NPY, POMC, AgRP, cocaine- and amphetamine related transcript (CART, corticotropin-releasing hormone (CRH and prepro-orexin (HCRT, and Y2 and Y5 neuropeptide Y, MC4 (melanocortin, OX1 and OX2 orexin receptors (Y2R, Y5R, MC4R, OX1R and OX2R, respectively was also explored. Our results show that orexin-A treatment does not significantly affect the components of energy expenditure, and glucose metabolism but reduces intraperitoneal fat deposit, adiposity and the expression of several brain neuropeptide receptors suggesting that peripheral orexin-A was able to reach the central nervous system. These findings establish that orexin-A treatment which is known for its activity as an inducer of tumor cell death, do have minor parallel consequence on energy homeostasis control.

Quantitative Metabolomics and Instationary 13C-Metabolic Flux Analysis Reveals Impact of Recombinant Protein Production on Trehalose and Energy Metabolism in Pichia pastoris

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Joel Jordà

2014-05-01

Full Text Available Pichia pastoris has been recognized as an effective host for recombinant protein production. In this work, we combine metabolomics and instationary 13C metabolic flux analysis (INST 13C-MFA using GC-MS and LC-MS/MS to evaluate the potential impact of the production of a Rhizopus oryzae lipase (Rol on P. pastoris central carbon metabolism. Higher oxygen uptake and CO2 production rates and slightly reduced biomass yield suggest an increased energy demand for the producing strain. This observation is further confirmed by 13C-based metabolic flux analysis. In particular, the flux through the methanol oxidation pathway and the TCA cycle was increased in the Rol-producing strain compared to the reference strain. Next to changes in the flux distribution, significant variations in intracellular metabolite concentrations were observed. Most notably, the pools of trehalose, which is related to cellular stress response, and xylose, which is linked to methanol assimilation, were significantly increased in the recombinant strain.

Energy metabolism and metabolomics response of Pacific white shrimp Litopenaeus vannamei to sulfide toxicity.

Science.gov (United States)

Li, Tongyu; Li, Erchao; Suo, Yantong; Xu, Zhixin; Jia, Yongyi; Qin, Jian G; Chen, Liqiao; Gu, Zhimin

2017-02-01

The toxicity and poisoning mechanisms of sulfide were studied in Litopenaeus vannamei from the perspective of energy metabolism and metabolomics. The lethal concentrations of sulfide in L. vannamei (LC50) at 24h, 48h, 72h, and 96h were determined. Sulfide at a concentration of 0, 1/10 (425.5μg/L), and 1/5 (851μg/L) of the LC 50 at 96h was used to test the metabolic responses of L. vannamei for 21days. The chronic exposure of shrimp to a higher sulfide concentration of 851μg/L decreased shrimp survival but did not affect weight gain or the hepatopancreas index. The glycogen content in the hepatopancreas and muscle and the activity of hepatopancreas cytochrome C oxidase of the shrimp exposed to all sulfide concentrations were significantly lower, and the serum glucose and lactic acid levels and lactic acid dehydrogenase activity were significantly lower than those in the control. Metabolomics assays showed that shrimp exposed to sulfide had lower amounts of serum pyruvic acid, succinic acid, glycine, alanine, and proline in the 425.5μg/L group and phosphate, succinic acid, beta-alanine, serine, and l-histidine in the 851μg/L group than in the control. Chronic sulfide exposure could disturb protein synthesis in shrimp but enhance gluconeogenesis and substrate absorption for ATP synthesis and tricarboxylic acid cycles to provide extra energy to cope with sulfide stress. Chronic sulfide exposure could adversely affect the health status of L. vannamei, as indicated by the high amounts of serum n-ethylmaleamic acid, pyroglutamic acid, aspartic acid and phenylalanine relative to the control. This study indicates that chronic exposure of shrimp to sulfide can decrease health and lower survival through functional changes in gluconeogenesis, protein synthesis and energy metabolism. Copyright © 2016 Elsevier B.V. All rights reserved.

Actions of juglone on energy metabolism in the rat liver

Energy Technology Data Exchange (ETDEWEB)

Saling, Simoni Cristina; Comar, Jurandir Fernando; Mito, Marcio Shigueaki; Peralta, Rosane Marina; Bracht, Adelar, E-mail: adebracht@uol.com.br

2011-12-15

Juglone is a phenolic compound used in popular medicine as a phytotherapic to treat inflammatory and infectious diseases. However, it also acts as an uncoupler of oxidative phosphorylation in isolated liver mitochondria and, thus, may interfere with the hepatic energy metabolism. The purpose of this work was to evaluate the effect of juglone on several metabolic parameters in the isolated perfused rat liver. Juglone, in the concentration range of 5 to 50 {mu}M, stimulated glycogenolysis, glycolysis and oxygen uptake. Gluconeogenesis from both lactate and alanine was inhibited with half-maximal effects at the concentrations of 14.9 and 15.7 {mu}M, respectively. The overall alanine transformation was increased by juglone, as indicated by the stimulated release of ammonia, urea, L-glutamate, lactate and pyruvate. A great increase (9-fold) in the tissue content of {alpha}-ketoglutarate was found, without a similar change in the L-glutamate content. The tissue contents of ATP were decreased, but those of ADP and AMP were increased. Experiments with isolated mitochondria fully confirmed previous notions about the uncoupling action of juglone. It can be concluded that juglone is active on metabolism at relatively low concentrations. In this particular it resembles more closely the classical uncoupler 2,4-dinitrophenol. Ingestion of high doses of juglone, thus, presents the same risks as the ingestion of 2,4-dinitrophenol which comprise excessive compromising of ATP production, hyperthermia and even death. Low doses, i.e., moderate consumption of natural products containing juglone, however, could be beneficial to health if one considers recent reports about the consequences of chronic mild uncoupling. -- Highlights: Black-Right-Pointing-Pointer We investigated how juglone acts on liver metabolism. Black-Right-Pointing-Pointer The actions on hepatic gluconeogenesis, glycolysis and ureogenesis. Black-Right-Pointing-Pointer Juglone stimulates glycolysis and ureagenesis and

Actions of juglone on energy metabolism in the rat liver

International Nuclear Information System (INIS)

Saling, Simoni Cristina; Comar, Jurandir Fernando; Mito, Márcio Shigueaki; Peralta, Rosane Marina; Bracht, Adelar

2011-01-01

Juglone is a phenolic compound used in popular medicine as a phytotherapic to treat inflammatory and infectious diseases. However, it also acts as an uncoupler of oxidative phosphorylation in isolated liver mitochondria and, thus, may interfere with the hepatic energy metabolism. The purpose of this work was to evaluate the effect of juglone on several metabolic parameters in the isolated perfused rat liver. Juglone, in the concentration range of 5 to 50 μM, stimulated glycogenolysis, glycolysis and oxygen uptake. Gluconeogenesis from both lactate and alanine was inhibited with half-maximal effects at the concentrations of 14.9 and 15.7 μM, respectively. The overall alanine transformation was increased by juglone, as indicated by the stimulated release of ammonia, urea, L-glutamate, lactate and pyruvate. A great increase (9-fold) in the tissue content of α-ketoglutarate was found, without a similar change in the L-glutamate content. The tissue contents of ATP were decreased, but those of ADP and AMP were increased. Experiments with isolated mitochondria fully confirmed previous notions about the uncoupling action of juglone. It can be concluded that juglone is active on metabolism at relatively low concentrations. In this particular it resembles more closely the classical uncoupler 2,4-dinitrophenol. Ingestion of high doses of juglone, thus, presents the same risks as the ingestion of 2,4-dinitrophenol which comprise excessive compromising of ATP production, hyperthermia and even death. Low doses, i.e., moderate consumption of natural products containing juglone, however, could be beneficial to health if one considers recent reports about the consequences of chronic mild uncoupling. -- Highlights: ► We investigated how juglone acts on liver metabolism. ► The actions on hepatic gluconeogenesis, glycolysis and ureogenesis. ► Juglone stimulates glycolysis and ureagenesis and inhibits gluconeogenesis. ► The cellular ATP content is diminished. ► Juglone can

Effect of Acute Negative and Positive Energy Balance on Basal Very-Low Density Lipoprotein Triglyceride Metabolism in Women

Science.gov (United States)

Bellou, Elena; Maraki, Maria; Magkos, Faidon; Botonaki, Helena; Panagiotakos, Demosthenes B.; Kavouras, Stavros A.; Sidossis, Labros S.

2013-01-01

Background Acute reduction in dietary energy intake reduces very low-density lipoprotein triglyceride (VLDL-TG) concentration. Although chronic dietary energy surplus and obesity are associated with hypertriglyceridemia, the effect of acute overfeeding on VLDL-TG metabolism is not known. Objective The aim of the present study was to investigate the effects of acute negative and positive energy balance on VLDL-TG metabolism in healthy women. Design Ten healthy women (age: 22.0±2.9 years, BMI: 21.2±1.3 kg/m2) underwent a stable isotopically labeled tracer infusion study to determine basal VLDL-TG kinetics after performing, in random order, three experimental trials on the previous day: i) isocaloric feeding (control) ii) hypocaloric feeding with a dietary energy restriction of 2.89±0.42 MJ and iii) hypercaloric feeding with a dietary energy surplus of 2.91±0.32 MJ. The three diets had the same macronutrient composition. Results Fasting plasma VLDL-TG concentrations decreased by ∼26% after hypocaloric feeding relative to the control trial (P = 0.037), owing to decreased hepatic VLDL-TG secretion rate (by 21%, P = 0.023) and increased VLDL-TG plasma clearance rate (by ∼12%, P = 0.016). Hypercaloric feeding increased plasma glucose concentration (P = 0.042) but had no effect on VLDL-TG concentration and kinetics compared to the control trial. Conclusion Acute dietary energy deficit (∼3MJ) leads to hypotriglyceridemia via a combination of decreased hepatic VLDL-TG secretion and increased VLDL-TG clearance. On the other hand, acute dietary energy surplus (∼3MJ) does not affect basal VLDL-TG metabolism but disrupts glucose homeostasis in healthy women. PMID:23533676

Effect of acute negative and positive energy balance on basal very-low density lipoprotein triglyceride metabolism in women.

Directory of Open Access Journals (Sweden)

Elena Bellou

Full Text Available BACKGROUND: Acute reduction in dietary energy intake reduces very low-density lipoprotein triglyceride (VLDL-TG concentration. Although chronic dietary energy surplus and obesity are associated with hypertriglyceridemia, the effect of acute overfeeding on VLDL-TG metabolism is not known. OBJECTIVE: The aim of the present study was to investigate the effects of acute negative and positive energy balance on VLDL-TG metabolism in healthy women. DESIGN: Ten healthy women (AGE: 22.0±2.9 years, BMI: 21.2±1.3 kg/m(2 underwent a stable isotopically labeled tracer infusion study to determine basal VLDL-TG kinetics after performing, in random order, three experimental trials on the previous day: i isocaloric feeding (control ii hypocaloric feeding with a dietary energy restriction of 2.89±0.42 MJ and iii hypercaloric feeding with a dietary energy surplus of 2.91±0.32 MJ. The three diets had the same macronutrient composition. RESULTS: Fasting plasma VLDL-TG concentrations decreased by ∼26% after hypocaloric feeding relative to the control trial (P = 0.037, owing to decreased hepatic VLDL-TG secretion rate (by 21%, P = 0.023 and increased VLDL-TG plasma clearance rate (by ∼12%, P = 0.016. Hypercaloric feeding increased plasma glucose concentration (P = 0.042 but had no effect on VLDL-TG concentration and kinetics compared to the control trial. CONCLUSION: Acute dietary energy deficit (∼3MJ leads to hypotriglyceridemia via a combination of decreased hepatic VLDL-TG secretion and increased VLDL-TG clearance. On the other hand, acute dietary energy surplus (∼3MJ does not affect basal VLDL-TG metabolism but disrupts glucose homeostasis in healthy women.

Interleaved MRI/MRS study of muscle perfusion, oxygenation and high energy phosphate metabolism in normal subjects and Becker's myopathic patients

International Nuclear Information System (INIS)

Toussaint, J.F.; Brillault-Salvat, C.; Giacomini, E.; Bloch, G.; Duboc, D.; Jehenson, P.

1998-01-01

We present the first results of a study comparing patients suffering from Becker's myopathy and normal volunteers. We simultaneously assessed perfusion, oxygenation and high-energy phosphate metabolism using an interleaved NMR/NMRS approach. Muscle metabolism does not seem to differ in Becker's patients, except for myoglobin reoxygenation rates. (authors)

Regulation of terpene metabolism. Final technical report, March 15, 1988--March 14, 1996

Energy Technology Data Exchange (ETDEWEB)

Croteau, R.

1996-12-31

This research focuses on the following topics: the biosynthesis and catabolism of monoterpenes; the organization of monoterpene metabolism; the developmental regulation of monoterpene metabolism; the flux control of precursor supply; and the integration of monoterpene and higher terpenoid metabolism.

III. Cellular ultrastructures in situ as key to understanding tumor energy metabolism: biological significance of the Warburg effect.

Science.gov (United States)

Witkiewicz, Halina; Oh, Phil; Schnitzer, Jan E

2013-01-01

Despite the universality of metabolic pathways, malignant cells were found to have their metabolism reprogrammed to generate energy by glycolysis even under normal oxygen concentrations (the Warburg effect). Therefore, the pathway energetically 18 times less efficient than oxidative phosphorylation was implicated to match increased energy requirements of growing tumors. The paradox was explained by an abnormally high rate of glucose uptake, assuming unlimited availability of substrates for tumor growth in vivo. However, ultrastructural analysis of tumor vasculature morphogenesis showed that the growing tissue regions did not have continuous blood supply and intermittently depended on autophagy for survival. Erythrogenic autophagy, and resulting ATP generation by glycolysis, appeared critical to initiating vasculature formation where it was missing. This study focused on ultrastructural features that reflected metabolic switch from aerobic to anaerobic. Morphological differences between and within different types of cells were evident in tissue sections. In cells undergoing nucleo-cytoplasmic conversion into erythrosomes (erythrogenesis), gradual changes led to replacing mitochondria with peroxisomes, through an intermediate form connected to endoplasmic reticulum. Those findings related to the issue of peroxisome biogenesis and to the phenomenon of hemogenic endothelium. Mitochondria were compacted also during mitosis. In vivo, cells that lost and others that retained capability to use oxygen coexisted side-by-side; both types were important for vasculature morphogenesis and tissue growth. Once passable, the new vasculature segment could deliver external oxygen and nutrients. Nutritional and redox status of microenvironment had similar effect on metabolism of malignant and non-malignant cells demonstrating the necessity to maintain structure-energy equivalence in all living cells. The role of glycolysis in initiating vasculature formation, and in progression of

The depressed central carbon and energy metabolisms is associated to the acquisition of levofloxacin resistance in Vibrio alginolyticus.

Science.gov (United States)

Cheng, Zhi-Xue; Yang, Man-Jun; Peng, Bo; Peng, Xuan-Xian; Lin, Xiang-Min; Li, Hui

2018-06-15

The overuse and misuse of antibiotics lead to bacterial antibiotic resistance, challenging human health and intensive cultivation. It is especially required to understand for the mechanism of antibiotic resistance to control antibiotic-resistant pathogens. The present study characterized the differential proteome of levofloxacin-resistant Vibrio alginolyticus with the most advanced iTRAQ quantitative proteomics technology. A total of 160 proteins of differential abundance were identified, where 70 were decreased and 90 were increased. Further analysis demonstrated that crucial metabolic pathways like TCA cycle were significantly down-regulated. qRT-PCR analysis demonstrated the decreased gene expression of glycolysis/gluconeogenesis, the TCA cycle, and fatty acid biosynthesis. Moreover, Na(+)-NQR complex gene expression, membrane potential and the adenylate energy charge ratio were decreased, indicating that the decreased central carbon metabolism is associated to the acquisition of levofloxacin resistance. Therefore, the reduced central carbon and energy metabolisms form a characteristic feature as fitness costs of V. alginolyticus in resistance to levofloxacin. The overuse and misuse of antibiotics lead to bacterial antibiotic resistance, challenging human health and intensive cultivation. Understanding for the antibiotic resistance mechanisms is especially required to control these antibiotic-resistant pathogens. The present study characterized the differential proteome of levofloxacin-resistant Vibrio alginolyticus using the most advanced iTRAQ quantitative proteomics technology. A total of 160 differential abundance of proteins were identified with 70 decreases and 90 increases by liquid chromatography matrix assisted laser desorption ionization mass spectrometry. Most interestingly, crucial metabolic pathways such as the TCA cycle sharply fluctuated. This is the first report that the reduced central carbon and energy metabolisms form a characteristic feature

Linking neuronal brain activity to the glucose metabolism.

Science.gov (United States)

Göbel, Britta; Oltmanns, Kerstin M; Chung, Matthias

2013-08-29

Energy homeostasis ensures the functionality of the entire organism. The human brain as a missing link in the global regulation of the complex whole body energy metabolism is subject to recent investigation. The goal of this study is to gain insight into the influence of neuronal brain activity on cerebral and peripheral energy metabolism. In particular, the tight link between brain energy supply and metabolic responses of the organism is of interest. We aim to identifying regulatory elements of the human brain in the whole body energy homeostasis. First, we introduce a general mathematical model describing the human whole body energy metabolism. It takes into account the two central roles of the brain in terms of energy metabolism. The brain is considered as energy consumer as well as regulatory instance. Secondly, we validate our mathematical model by experimental data. Cerebral high-energy phosphate content and peripheral glucose metabolism are measured in healthy men upon neuronal activation induced by transcranial direct current stimulation versus sham stimulation. By parameter estimation we identify model parameters that provide insight into underlying neurophysiological processes. Identified parameters reveal effects of neuronal activity on regulatory mechanisms of systemic glucose metabolism. Our examinations support the view that the brain increases its glucose supply upon neuronal activation. The results indicate that the brain supplies itself with energy according to its needs, and preeminence of cerebral energy supply is reflected. This mechanism ensures balanced cerebral energy homeostasis. The hypothesis of the central role of the brain in whole body energy homeostasis as active controller is supported.

A failure in energy metabolism and antioxidant uptake precede symptoms of Huntington’s disease in mice

Science.gov (United States)

Acuña, Aníbal I.; Esparza, Magdalena; Kramm, Carlos; Beltrán, Felipe A.; Parra, Alejandra V.; Cepeda, Carlos; Toro, Carlos A.; Vidal, René L.; Hetz, Claudio; Concha, Ilona I.; Brauchi, Sebastián; Levine, Michael S.; Castro, Maite A.

2013-12-01

Huntington’s disease has been associated with a failure in energy metabolism and oxidative damage. Ascorbic acid is a powerful antioxidant highly concentrated in the brain where it acts as a messenger, modulating neuronal metabolism. Using an electrophysiological approach in R6/2 HD slices, we observe an abnormal ascorbic acid flux from astrocytes to neurons, which is responsible for alterations in neuronal metabolic substrate preferences. Here using striatal neurons derived from knock-in mice expressing mutant huntingtin (STHdhQ cells), we study ascorbic acid transport. When extracellular ascorbic acid concentration increases, as occurs during synaptic activity, ascorbic acid transporter 2 (SVCT2) translocates to the plasma membrane, ensuring optimal ascorbic acid uptake for neurons. In contrast, SVCT2 from cells that mimic HD symptoms (dubbed HD cells) fails to reach the plasma membrane under the same conditions. We reason that an early impairment of ascorbic acid uptake in HD neurons could lead to early metabolic failure promoting neuronal death.

Proteome analysis of schizophrenia patients Wernicke's area reveals an energy metabolism dysregulation

Directory of Open Access Journals (Sweden)

Marangoni Sérgio

2009-04-01

Full Text Available Abstract Background Schizophrenia is likely to be a consequence of DNA alterations that, together with environmental factors, will lead to protein expression differences and the ultimate establishment of the illness. The superior temporal gyrus is implicated in schizophrenia and executes functions such as the processing of speech, language skills and sound processing. Methods We performed an individual comparative proteome analysis using two-dimensional gel electrophoresis of 9 schizophrenia and 6 healthy control patients' left posterior superior temporal gyrus (Wernicke's area – BA22p identifying by mass spectrometry several protein expression alterations that could be related to the disease. Results Our analysis revealed 11 downregulated and 14 upregulated proteins, most of them related to energy metabolism. Whereas many of the identified proteins have been previously implicated in schizophrenia, such as fructose-bisphosphate aldolase C, creatine kinase and neuron-specific enolase, new putative disease markers were also identified such as dihydrolipoyl dehydrogenase, tropomyosin 3, breast cancer metastasis-suppressor 1, heterogeneous nuclear ribonucleoproteins C1/C2 and phosphate carrier protein, mitochondrial precursor. Besides, the differential expression of peroxiredoxin 6 (PRDX6 and glial fibrillary acidic protein (GFAP were confirmed by western blot in schizophrenia prefrontal cortex. Conclusion Our data supports a dysregulation of energy metabolism in schizophrenia as well as suggests new markers that may contribute to a better understanding of this complex disease.

Elucidating the Metabolic Plasticity of Cancer: Mitochondrial Reprogramming and Hybrid Metabolic States

Directory of Open Access Journals (Sweden)

Dongya Jia

2018-03-01

Full Text Available Aerobic glycolysis, also referred to as the Warburg effect, has been regarded as the dominant metabolic phenotype in cancer cells for a long time. More recently, it has been shown that mitochondria in most tumors are not defective in their ability to carry out oxidative phosphorylation (OXPHOS. Instead, in highly aggressive cancer cells, mitochondrial energy pathways are reprogrammed to meet the challenges of high energy demand, better utilization of available fuels and macromolecular synthesis for rapid cell division and migration. Mitochondrial energy reprogramming is also involved in the regulation of oncogenic pathways via mitochondria-to-nucleus retrograde signaling and post-translational modification of oncoproteins. In addition, neoplastic mitochondria can engage in crosstalk with the tumor microenvironment. For example, signals from cancer-associated fibroblasts can drive tumor mitochondria to utilize OXPHOS, a process known as the reverse Warburg effect. Emerging evidence shows that cancer cells can acquire a hybrid glycolysis/OXPHOS phenotype in which both glycolysis and OXPHOS can be utilized for energy production and biomass synthesis. The hybrid glycolysis/OXPHOS phenotype facilitates metabolic plasticity of cancer cells and may be specifically associated with metastasis and therapy-resistance. Moreover, cancer cells can switch their metabolism phenotypes in response to external stimuli for better survival. Taking into account the metabolic heterogeneity and plasticity of cancer cells, therapies targeting cancer metabolic dependency in principle can be made more effective.

The Changes of Energy Interactions between Nucleus Function and Mitochondria Functions Causing Transmutation of Chronic Inflammation into Cancer Metabolism.

Science.gov (United States)

Ponizovskiy, Michail R

2016-01-01

Interactions between nucleus and mitochondria functions induce the mechanism of maintenance stability of cellular internal energy according to the first law of thermodynamics in able-bodied cells and changes the mechanisms of maintenance stability of cellular internal energy creating a transition stationary state of ablebodied cells into quasi-stationary pathologic states of acute inflammation transiting then into chronic inflammation and then transmuting into cancer metabolism. The mechanisms' influences of intruding etiologic pathologic agents (microbe, virus, etc.) lead to these changes of energy interactions between nucleus and mitochondria functions causing general acute inflammation, then passing into local chronic inflammation, and reversing into cancer metabolism transmutation. Interactions between biochemical processes and biophysical processes of cellular capacitors' operations create a supplementary mechanism of maintenance stability of cellular internal energy in the norm and in pathology. Discussion of some scientific works eliminates doubts of the authors of these works.

The Share of Renewable Sources in Gross Final Energy Consumption in Croatia in 2014

International Nuclear Information System (INIS)

Kalea, M.

2016-01-01

Eurostat, the statistical agency of the European Union follows the share of renewable energy in gross final energy consumption for many years. The EU Directive 2009/28/EC on renewable energy sources takes as a key indicator of developments in the use of renewable sources of individual member states precisely this indicator. This directive has set the goals of testimony percentage value of the shares that each member state must be achieved by 2020. These are the objectives for each country-member generally different, depending on the starting achieved share (2005), about the possibilities of individual forms of renewable energy and the wealth of individual member states. The goals are set so that in the European Union as a whole in 2020 it reached the share of renewables by 20 percent. Incidentally, Croatia is the default target is also 20 percent, a marginal tasks are 10 percent (for Malta) and 49 percent (for Sweden). At the same time, the Directive sets all member states equal to the target share of energy from renewable sources in the total energy demand for the needs of road transport by 10 percent by 2020. This short work of explanation is very strictly defined way of determining the share of renewable sources in gross final energy consumption, including the data for Croatia in 2014.(author).

Griffith energy project final environmental impact statement

International Nuclear Information System (INIS)

1999-03-01

Griffith Energy Limited Liability Corporation (Griffith) proposes to construct and operate the Griffith Energy Project (Project), a natural gas-fired, combined cycle power plant, on private lands south of Kingman, Arizona. The Project would be a merchant plant which means that it is not owned by a utility and there is currently no long-term commitment or obligation by any utility to purchase the capacity and energy generated by the power plant. Griffith applied to interconnect its proposed power plant with the Western Area Power Administration's (Western) Pacific Northwest-Pacific Southwest Intertie and Parker-Davis transmission systems. Western, as a major transmission system owner, needs to provide access to its transmission system when it is requested by an eligible organization per existing policies, regulations and laws. The proposed interconnection would integrate the power generated by the Project into the regional transmission grid and would allow Griffith to supply its power to the competitive electric wholesale market. Based on the application, Western's proposed action is to enter into an interconnection and construction agreement with Griffith for the requested interconnections. The proposed action includes the power plant, water wells and transmission line, natural gas pipelines, new electrical transmission lines and a substation, upgrade of an existing transmission line, and access road to the power plant. Construction of segments of the transmission lines and a proposed natural gas pipeline also require a grant of right-of-way across Federal lands administered by the Bureau of Land Management. Public comments on the Draft EIS are addressed in the Final EIS, including addenda and modifications made as a result of the comments and/or new information

Griffith Energy Project Final Environmental Impact Statement

Energy Technology Data Exchange (ETDEWEB)

N/A

1999-04-02

Griffith Energy Limited Liability Corporation (Griffith) proposes to construct and operate the Griffith Energy Project (Project), a natural gas-fuel, combined cycle power plant, on private lands south of Kingman, Ariz. The Project would be a ''merchant plant'' which means that it is not owned by a utility and there is currently no long-term commitment or obligation by any utility to purchase the capacity and energy generated by the power plant. Griffith applied to interconnect its proposed power plant with the Western Area Power Administration's (Western) Pacific Northwest-Pacific Southwest Intertie and Parker-Davis transmission systems. Western, as a major transmission system owner, needs to provide access to its transmission system when it is requested by an eligible organization per existing policies, regulations and laws. The proposed interconnection would integrate the power generated by the Project into the regional transmission grid and would allow Griffith to supply its power to the competitive electric wholesale market. Based on the application, Western's proposed action is to enter into an interconnection and construction agreement with Griffith for the requested interconnections. The proposed action includes the power plant, water wells and transmission line, natural gas pipelines, new electrical transmission lines and a substation, upgrade of an existing transmission line, and access road to the power plant. Construction of segments of the transmission lines and a proposed natural gas pipeline also require a grant of right-of-way across Federal lands administered by the Bureau of Land Management. Public comments on the Draft EIS are addressed in the Final EIS, including addenda and modifications made as a result of the comments and/or new information.

Metabolic changes in malnutrition.

Science.gov (United States)

Emery, P W

2005-10-01

This paper is concerned with malnutrition caused by inadequate intake of all the major nutrients rather than deficiency diseases relating to a single micronutrient. Three common situations are recognised: young children in third world countries with protein-energy malnutrition; adults in the same countries who are chronically adapted to subsisting on marginally inadequate diets; and patients who become malnourished as a result of chronic diseases. In all these situations infectious diseases are often also present, and this complicates the interpretation of biochemical and physiological observations. The metabolic response to starvation is primarily concerned with maintaining a supply of water-soluble substrates to supply energy to the brain. Thus there is an initial rise in metabolic rate, reflecting gluconeogenic activity. As fasting progresses, gluconeogenesis is suppressed to minimise muscle protein breakdown and ketones become the main fuel for the brain. With chronic underfeeding the basal metabolic rate per cell appears to fall, but the mechanistic basis for this is not clear. The main adaptation to chronic energy deficiency is slow growth and low adult body size, although the reduction in energy requirement achieved by this is partially offset by the preservation of the more metabolically active organs at the expense of muscle, which has a lower metabolic rate. The interaction between malnutrition and the metabolic response to trauma has been studied using an animal model. The rise in energy expenditure and urinary nitrogen excretion following surgery were significantly attenuated in malnourished rats, suggesting that malnutrition impairs the ability of the body to mobilise substrates to support inflammatory and reparative processes. However, the healing process in wounded muscle remained unimpaired in malnutrition, suggesting that this process has a high biological priority.

Diurnal variation of the human adipose transcriptome and the link to metabolic disease

Directory of Open Access Journals (Sweden)

Lamb John

2009-02-01

Full Text Available Abstract Background Circadian (diurnal rhythm is an integral part of the physiology of the body; specifically, sleep, feeding behavior and metabolism are tightly linked to the light-dark cycle dictated by earth's rotation. Methods The present study examines the effect of diurnal rhythm on gene expression in the subcutaneous adipose tissue of overweight to mildly obese, healthy individuals. In this well-controlled clinical study, adipose biopsies were taken in the morning, afternoon and evening from individuals in three study arms: treatment with the weight loss drug sibutramine/fasted, placebo/fed and placebo/fasted. Results The results indicated that diurnal rhythm was the most significant driver of gene expression variation in the human adipose tissue, with at least 25% of the genes having had significant changes in their expression levels during the course of the day. The mRNA expression levels of core clock genes at a specific time of day were consistent across multiple subjects on different days in all three arms, indicating robust diurnal regulation irrespective of potential confounding factors. The genes essential for energy metabolism and tissue physiology were part of the diurnal signature. We hypothesize that the diurnal transition of the expression of energy metabolism genes reflects the shift in the adipose tissue from an energy-expending state in the morning to an energy-storing state in the evening. Consistent with this hypothesis, the diurnal transition was delayed by fasting and treatment with sibutramine. Finally, an in silico comparison of the diurnal signature with data from the publicly-available Connectivity Map demonstrated a significant association with transcripts that were repressed by mTOR inhibitors, suggesting a possible link between mTOR signaling, diurnal gene expression and metabolic regulation. Conclusion Diurnal rhythm plays an important role in the physiology and regulation of energy metabolism in the adipose

The Deep Correlation between Energy Metabolism and Reproduction: A View on the Effects of Nutrition for Women Fertility

OpenAIRE

Fontana, Roberta; Della Torre, Sara

2016-01-01

In female mammals, mechanisms have been developed, throughout evolution, to integrate environmental, nutritional and hormonal cues in order to guarantee reproduction in favorable energetic conditions and to inhibit it in case of food scarcity. This metabolic strategy could be an advantage in nutritionally poor environments, but nowadays is affecting women’s health. The unlimited availability of nutrients, in association with reduced energy expenditure, leads to alterations in many metabolic p...

Energy and lipid metabolism during direct and diapause development in a pierid butterfly.

Science.gov (United States)

Lehmann, Philipp; Pruisscher, Peter; Posledovich, Diana; Carlsson, Mikael; Käkelä, Reijo; Tang, Patrik; Nylin, Sören; Wheat, Christopher W; Wiklund, Christer; Gotthard, Karl

2016-10-01

Diapause is a fundamental component of the life cycle in the majority of insects living in environments characterized by strong seasonality. The present study addresses poorly understood associations and trade-offs between endogenous diapause duration, thermal sensitivity of development, energetic cost of development and cold tolerance. Diapause intensity, metabolic rate trajectories and lipid profiles of directly developing and diapausing animals were studied using pupae and adults of Pieris napi butterflies from a population in which endogenous diapause has been well studied. Endogenous diapause was terminated after 3 months and termination required chilling. Metabolic and post-diapause development rates increased with diapause duration, while the metabolic cost of post-diapause development decreased, indicating that once diapause is terminated, development proceeds at a low rate even at low temperature. Diapausing pupae had larger lipid stores than the directly developing pupae, and lipids constituted the primary energy source during diapause. However, during diapause, lipid stores did not decrease. Thus, despite lipid catabolism meeting the low energy costs of the diapausing pupae, primary lipid store utilization did not occur until the onset of growth and metamorphosis in spring. In line with this finding, diapausing pupae contained low amounts of mitochondria-derived cardiolipins, which suggests a low capacity for fatty acid β-oxidation. While ontogenic development had a large effect on lipid and fatty acid profiles, only small changes in these were seen during diapause. The data therefore indicate that the diapause lipidomic phenotype is developed early, when pupae are still at high temperature, and retained until post-diapause development. © 2016. Published by The Company of Biologists Ltd.

Energy analysis for a sustainable future multi-scale integrated analysis of societal and ecosystem metabolism

CERN Document Server

Giampietro, Mario; Sorman, Alevgül H

2013-01-01

The vast majority of the countries of the world are now facing an imminent energy crisis, particularly the USA, China, India, Japan and EU countries, but also developing countries having to boost their economic growth precisely when more powerful economies will prevent them from using the limited supply of fossil energy. Despite this crisis, current protocols of energy accounting have been developed for dealing with fossil energy exclusively and are therefore not useful for the analysis of alternative energy sources. The first part of the book illustrates the weakness of existing analyses of energy problems: the science of energy was born and developed neglecting the issue of scale. The authors argue that it is necessary to adopt more complex protocols of accounting and analysis in order to generate robust energy scenarios and effective assessments of the quality of alternative energy sources. The second part of the book introduces the concept of energetic metabolism of modern societies and uses empirical res...

Effects of medium-chain triglycerides on intestinal morphology and energy metabolism of intrauterine growth retarded weanling piglets.

Science.gov (United States)

Zhang, Li-Li; Zhang, Hao; Li, Yue; Wang, Tian

2017-06-01

It has been shown that there is a relationship between intrauterine growth retardation (IUGR) and postnatal intestinal damage involved in energy deficits. Therefore, the present study was conducted to investigate the effect of medium-chain triglycerides (MCT) on the intestinal morphology, intestinal function and energy metabolism of piglets with IUGR. At weaning (21 ± 1.1 d of age), 24 IUGR piglets and 24 normal birth weight (NBW) piglets were selected according to their birth weights (BW) (IUGR: 0.95 ± 0.04 kg BW; NBW: 1.58 ± 0.04 kg BW) and their weights at the time of weaning (IUGR: 5.26 ± 0.15 kg BW; NBW: 6.98 ± 0.19 kg BW). The piglets were fed a diet of either long-chain triglycerides (LCT) (containing 5% LCT) or MCT (containing 1% LCT and 4% MCT) for 28 d. Then, the piglets' intestinal morphology, biochemical parameters and mRNA abundance related to intestinal damage and energy metabolism were determined. IUGR was found to impair intestinal morphology, with evidence of decreased villus height and increased crypt depth; however, these negative effects of IUGR were ameliorated by MCT treatment. IUGR piglets showed compromised intestinal digestion and absorption functions when compared with NBW piglets. However, feeding MCT increased the maltase activity in the jejunum and alleviated IUGR-induced reductions in plasma d-xylose concentrations and jejunal sucrase activity. IUGR decreased the efficiency of the piglets' intestinal energy metabolism; however, piglets fed an MCT diet exhibited increased adenosine triphosphate (ATP) concentrations and ATP synthase F1 complex beta polypeptide expression, as well as decreased adenosine monophosphate-activated kinase alpha 1 expression in the jejunum of piglets. In addition, up-regulation of the piglets' citrate synthase and succinate dehydrogenase levels was found to occur following MCT treatment at both the activity and the transcriptional levels of the jejunum. Therefore, it can be postulated that

Fused Silica Final Optics for Inertial Fusion Energy: Radiation Studies and System-Level Analysis

International Nuclear Information System (INIS)

Latkowski, Jeffery F.; Kubota, Alison; Caturla, Maria J.; Dixit, Sham N.; Speth, Joel A.; Payne, Stephen A.

2003-01-01

The survivability of the final optic, which must sit in the line of sight of high-energy neutrons and gamma rays, is a key issue for any laser-driven inertial fusion energy (IFE) concept. Previous work has concentrated on the use of reflective optics. Here, we introduce and analyze the use of a transmissive final optic for the IFE application. Our experimental work has been conducted at a range of doses and dose rates, including those comparable to the conditions at the IFE final optic. The experimental work, in conjunction with detailed analysis, suggests that a thin, fused silica Fresnel lens may be an attractive option when used at a wavelength of 351 nm. Our measurements and molecular dynamics simulations provide convincing evidence that the radiation damage, which leads to optical absorption, not only saturates but that a 'radiation annealing' effect is observed. A system-level description is provided, including Fresnel lens and phase plate designs

Environmental oxygen tension regulates the energy metabolism and self-renewal of human embryonic stem cells.

Science.gov (United States)

Forristal, Catherine E; Christensen, David R; Chinnery, Fay E; Petruzzelli, Raffaella; Parry, Kate L; Sanchez-Elsner, Tilman; Houghton, Franchesca D

2013-01-01

Energy metabolism is intrinsic to cell viability but surprisingly has been little studied in human embryonic stem cells (hESCs). The current study aims to investigate the effect of environmental O2 tension on carbohydrate utilisation of hESCs. Highly pluripotent hESCs cultured at 5% O2 consumed significantly more glucose, less pyruvate and produced more lactate compared to those maintained at 20% O2. Moreover, hESCs cultured at atmospheric O2 levels expressed significantly less OCT4, SOX2 and NANOG than those maintained at 5% O2. To determine whether this difference in metabolism was a reflection of the pluripotent state, hESCs were cultured at 5% O2 in the absence of FGF2 for 16 hours leading to a significant reduction in the expression of SOX2. In addition, these cells consumed less glucose and produced significantly less lactate compared to those cultured in the presence of FGF2. hESCs maintained at 5% O2 were found to consume significantly less O2 than those cultured in the absence of FGF2, or at 20% O2. GLUT1 expression correlated with glucose consumption and using siRNA and chromatin immunoprecipitation was found to be directly regulated by hypoxia inducible factor (HIF)-2α at 5% O2. In conclusion, highly pluripotent cells associated with hypoxic culture consume low levels of O2, high levels of glucose and produce large amounts of lactate, while at atmospheric conditions glucose consumption and lactate production are reduced and there is an increase in oxidative metabolism. These data suggest that environmental O2 regulates energy metabolism and is intrinsic to the self-renewal of hESCs.

Beneficial effects on host energy metabolism of short-chain fatty acids and vitamins produced by commensal and probiotic bacteria.

Science.gov (United States)

LeBlanc, Jean Guy; Chain, Florian; Martín, Rebeca; Bermúdez-Humarán, Luis G; Courau, Stéphanie; Langella, Philippe

2017-05-08

The aim of this review is to summarize the effect in host energy metabolism of the production of B group vitamins and short chain fatty acids (SCFA) by commensal, food-grade and probiotic bacteria, which are also actors of the mammalian nutrition. The mechanisms of how these microbial end products, produced by these bacterial strains, act on energy metabolism will be discussed. We will show that these vitamins and SCFA producing bacteria could be used as tools to recover energy intakes by either optimizing ATP production from foods or by the fermentation of certain fibers in the gastrointestinal tract (GIT). Original data are also presented in this work where SCFA (acetate, butyrate and propionate) and B group vitamins (riboflavin, folate and thiamine) production was determined for selected probiotic bacteria.

Day-night changes of energy-rich compounds in crassulacean acid metabolism (CAM) species utilizing hexose and starch.

Science.gov (United States)

Chen, Li-Song; Nose, Akihiro

2004-09-01

Plants with crassulacean acid metabolism (CAM) can be divided into two groups according to the major carbohydrates used for malic acid synthesis, either polysaccharide (starch) or monosaccharide (hexose). This is related to the mechanism and affects energy metabolism in the two groups. In Kalanchoë pinnata and K. daigremontiana, which utilize starch, ATP-dependent phosphofructokinase (tonoplast inorganic pyrophosphatase) activity is greater than inorganic pyrophosphate-dependent phosphofructokinase (tonoplast adenosine triphosphatase) activity, but the reverse is the case in pineapple (Ananas comosus) utilizing hexose. To test the hypothesis that the energy metabolism of the two groups differs, day-night changes in the contents of ATP, ADP, AMP, inorganic phosphate (Pi), phosphoenolpyruvate (PEP) and inorganic pyrophosphate (PPi) in K. pinnata and K. daigremontiana leaves and in pineapple chlorenchyma were analysed. The contents of energy-rich compounds were measured spectrophotometrically in extracts of tissue sampled in the light and dark, using potted plants, kept for 15 d before the experiments in a growth chamber. In the three species, ATP content and adenylate energy charge (AEC) increased in the dark and decreased in the light, in contrast to ADP and AMP. Changes in ATP and AEC were greater in Kalanchoë leaves than in pineapple chlorenchyma. PPi content in the three species increased in the dark, but on illumination it decreased rapidly and substantially, remaining little changed through the rest of the light period. Pi content of Kalanchoë leaves did not change between dark and light, whereas Pi in pineapple chlorenchyma increased in the dark and decreased in the light, and the changes were far greater than in Kalanchoë leaves. Light-dark changes in PEP content in the three species were similar. These results corroborate our hypothesis that day-night changes in the contents of energy-rich compounds differ between CAM species and are related to the

Size dependence in non-sperm ejaculate production is reflected in daily energy expenditure and resting metabolic rate.

Science.gov (United States)

Friesen, Christopher R; Powers, Donald R; Copenhaver, Paige E; Mason, Robert T

2015-05-01

The non-sperm components of an ejaculate, such as copulatory plugs, can be essential to male reproductive success. But the costs of these ejaculate components are often considered trivial. In polyandrous species, males are predicted to increase energy allocation to the production of non-sperm components, but this allocation is often condition dependent and the energetic costs of their production have never been quantified. Red-sided garter snakes (Thamnophis sirtalis parietalis) are an excellent model with which to quantify the energetic costs of non-sperm components of the ejaculate as they exhibit a dissociated reproductive pattern in which sperm production is temporally disjunct from copulatory plug production, mating and plug deposition. We estimated the daily energy expenditure and resting metabolic rate of males after courtship and mating, and used bomb calorimetry to estimate the energy content of copulatory plugs. We found that both daily energy expenditure and resting metabolic rate were significantly higher in small mating males than in courting males, and a single copulatory plug without sperm constitutes 5-18% of daily energy expenditure. To our knowledge, this is the first study to quantify the energetic expense of size-dependent ejaculate strategies in any species. © 2015. Published by The Company of Biologists Ltd.

The gut hormone ghrelin partially reverses energy substrate metabolic alterations in the failing heart.

Science.gov (United States)

Mitacchione, Gianfranco; Powers, Jeffrey C; Grifoni, Gino; Woitek, Felix; Lam, Amy; Ly, Lien; Settanni, Fabio; Makarewich, Catherine A; McCormick, Ryan; Trovato, Letizia; Houser, Steven R; Granata, Riccarda; Recchia, Fabio A

2014-07-01

The gut-derived hormone ghrelin, especially its acylated form, plays a major role in the regulation of systemic metabolism and exerts also relevant cardioprotective effects; hence, it has been proposed for the treatment of heart failure (HF). We tested the hypothesis that ghrelin can directly modulate cardiac energy substrate metabolism. We used chronically instrumented dogs, 8 with pacing-induced HF and 6 normal controls. Human des-acyl ghrelin [1.2 nmol/kg per hour] was infused intravenously for 15 minutes, followed by washout (rebaseline) and infusion of acyl ghrelin at the same dose. (3)H-oleate and (14)C-glucose were coinfused and arterial and coronary sinus blood sampled to measure cardiac free fatty acid and glucose oxidation and lactate uptake. As expected, cardiac substrate metabolism was profoundly altered in HF because baseline oxidation levels of free fatty acids and glucose were, respectively, >70% lower and >160% higher compared with control. Neither des-acyl ghrelin nor acyl ghrelin significantly affected function and metabolism in normal hearts. However, in HF, des-acyl and acyl ghrelin enhanced myocardial oxygen consumption by 10.2±3.5% and 9.9±3.7%, respectively (Pmetabolism in normal dogs, whereas they enhance free fatty acid oxidation and reduce glucose oxidation in HF dogs, thus partially correcting metabolic alterations in HF. This novel mechanism might contribute to the cardioprotective effects of ghrelin in HF. © 2014 American Heart Association, Inc.

Sneaker Male Squid Produce Long-lived Spermatozoa by Modulating Their Energy Metabolism *

Science.gov (United States)

Hirohashi, Noritaka; Tamura-Nakano, Miwa; Nakaya, Fumio; Iida, Tomohiro; Iwata, Yoko

2016-01-01

Spermatozoa released by males should remain viable until fertilization. Hence, sperm longevity is governed by intrinsic and environmental factors in accordance with the male mating strategy. However, whether intraspecific variation of insemination modes can impact sperm longevity remains to be elucidated. In the squid Heterololigo bleekeri, male dimorphism (consort and sneaker) is linked to two discontinuous insemination modes that differ in place and time. Notably, only sneaker male spermatozoa inseminated long before egg spawning can be stored in the seminal receptacle. We found that sneaker spermatozoa exhibited greater persistence in fertilization competence and flagellar motility than consort ones because of a larger amount of flagellar glycogen. Sneaker spermatozoa also showed higher capacities in glucose uptake and lactate efflux. Lactic acidosis was considered to stabilize CO2-triggered self-clustering of sneaker spermatozoa, thus establishing hypoxia-induced metabolic changes and sperm survival. These results, together with comparative omics analyses, suggest that postcopulatory reproductive contexts define sperm longevity by modulating the inherent energy levels and metabolic pathways. PMID:27385589

Omega-3 Fatty Acids and Mood Stabilizers Alter Behavioural and Energy Metabolism Parameters in Animals Subjected to an Animal Model of Mania Induced by Fenproporex.

Science.gov (United States)

Cancelier, Kizzy; Gomes, Lara M; Carvalho-Silva, Milena; Teixeira, Letícia J; Rebelo, Joyce; Mota, Isabella T; Arent, Camila O; Mariot, Edemilson; Kist, Luiza W; Bogo, Maurício R; Quevedo, João; Scaini, Giselli; Streck, Emilio L

2017-08-01

Studies have shown that changes in energy metabolism are involved in the pathophysiology of bipolar disorder (BD). It was suggested that omega-3 (ω3) fatty acids have beneficial properties in the central nervous system and that this fatty acid plays an important role in energy metabolism. Therefore, the study aimed to evaluate the effect of ω3 fatty acids alone and in combination with lithium (Li) or valproate (VPA) on behaviour and parameters of energy metabolism in an animal model of mania induced by fenproporex. Our results showed that co-administration of ω3 fatty acids and Li was able to prevent and reverse the increase in locomotor and exploratory activity induced by fenproporex. The combination of ω3 fatty acids with VPA was only able to prevent the fenproporex-induced hyperactivity. For the energy metabolism parameters, our results showed that the administration of Fen for the reversal or prevention protocol inhibited the activities of succinate dehydrogenase, complex II and complex IV in the hippocampus. However, hippocampal creatine kinase (CK) activity was decreased only for the reversal protocol. The ω3 fatty acids, alone and in combination with VPA or Li, prevented and reversed the decrease in complex II, IV and succinate dehydrogenase activity, whereas the decrease in CK activity was only reversed after the co-administration of ω3 fatty acids and VPA. In conclusion, our results showed that the ω3 fatty acids combined with VPA or Li were able to prevent and reverse manic-like hyperactivity and the inhibition of energy metabolism in the hippocampus, suggesting that ω3 fatty acids may play an important role in the modulation of behavioural parameters and energy metabolism.

The Deep Correlation between Energy Metabolism and Reproduction: A View on the Effects of Nutrition for Women Fertility.

Science.gov (United States)

Fontana, Roberta; Della Torre, Sara

2016-02-11

In female mammals, mechanisms have been developed, throughout evolution, to integrate environmental, nutritional and hormonal cues in order to guarantee reproduction in favorable energetic conditions and to inhibit it in case of food scarcity. This metabolic strategy could be an advantage in nutritionally poor environments, but nowadays is affecting women's health. The unlimited availability of nutrients, in association with reduced energy expenditure, leads to alterations in many metabolic pathways and to impairments in the finely tuned inter-relation between energy metabolism and reproduction, thereby affecting female fertility. Many energetic states could influence female reproductive health being under- and over-weight, obesity and strenuous physical activity are all conditions that alter the profiles of specific hormones, such as insulin and adipokines, thus impairing women fertility. Furthermore, specific classes of nutrients might affect female fertility by acting on particular signaling pathways. Dietary fatty acids, carbohydrates, proteins and food-associated components (such as endocrine disruptors) have per se physiological activities and their unbalanced intake, both in quantitative and qualitative terms, might impair metabolic homeostasis and fertility in premenopausal women. Even though we are far from identifying a "fertility diet", lifestyle and dietary interventions might represent a promising and invaluable strategy to manage infertility in premenopausal women.

The Deep Correlation between Energy Metabolism and Reproduction: A View on the Effects of Nutrition for Women Fertility

Directory of Open Access Journals (Sweden)

Roberta Fontana

2016-02-01

Full Text Available In female mammals, mechanisms have been developed, throughout evolution, to integrate environmental, nutritional and hormonal cues in order to guarantee reproduction in favorable energetic conditions and to inhibit it in case of food scarcity. This metabolic strategy could be an advantage in nutritionally poor environments, but nowadays is affecting women’s health. The unlimited availability of nutrients, in association with reduced energy expenditure, leads to alterations in many metabolic pathways and to impairments in the finely tuned inter-relation between energy metabolism and reproduction, thereby affecting female fertility. Many energetic states could influence female reproductive health being under- and over-weight, obesity and strenuous physical activity are all conditions that alter the profiles of specific hormones, such as insulin and adipokines, thus impairing women fertility. Furthermore, specific classes of nutrients might affect female fertility by acting on particular signaling pathways. Dietary fatty acids, carbohydrates, proteins and food-associated components (such as endocrine disruptors have per se physiological activities and their unbalanced intake, both in quantitative and qualitative terms, might impair metabolic homeostasis and fertility in premenopausal women. Even though we are far from identifying a “fertility diet”, lifestyle and dietary interventions might represent a promising and invaluable strategy to manage infertility in premenopausal women.

Metabolic learning and memory formation by the brain influence systemic metabolic homeostasis

Science.gov (United States)

Zhang, Yumin; Liu, Gang; Yan, Jingqi; Zhang, Yalin; Li, Bo; Cai, Dongsheng

2015-01-01

Metabolic homeostasis is regulated by the brain, whether this regulation involves learning and memory of metabolic information remains unexplored. Here we use a calorie-based, taste-independent learning/memory paradigm to show that Drosophila form metabolic memories that help balancing food choice with caloric intake; however, this metabolic learning or memory is lost under chronic high-calorie feeding. We show that loss of individual learning/memory-regulating genes causes a metabolic learning defect, leading to elevated trehalose and lipids levels. Importantly, this function of metabolic learning requires not only the mushroom body but the hypothalamus-like pars intercerebralis, while NF-κB activation in the pars intercerebralis mimics chronic overnutrition in that it causes metabolic learning impairment and disorders. Finally, we evaluate this concept of metabolic learning/memory in mice, suggesting the hypothalamus is involved in a form of nutritional learning and memory, which is critical for determining resistance or susceptibility to obesity. In conclusion, our data indicate the brain, and potentially the hypothalamus, direct metabolic learning and the formation of memories, which contribute to the control of systemic metabolic homeostasis. PMID:25848677

[Study on gene differential expressions of substance and energy metabolism in chronic superficial gastritis patients of Pi deficiency syndrome and of pi-wei hygropyrexia syndrome].

Science.gov (United States)

Yang, Ze-Min; Chen, Wei-Wen; Wang, Ying-Fang

2012-09-01

To analyze the metabolic levels of energy and substance in chronic superficial gastritis (CSG) patients of Pi deficiency syndrome (PDS) and of Pi-Wei hygropyrexia syndrome (PWHS), including lipid, protein, nucleic acid, carbohydrate, trace element, and energy metabolism, and to study the pathogenesis mechanism of PDS from substance and energy metabolisms. Recruited were 8 CSG patients who visited at First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine and Guangdong Provincial Hospital of Traditional Chinese Medicine from June 2004 to March 2005, including 4 patients of PDS and 4 of PWHS. Their gastric mucosae were used for experiments of DNA microarray. The dual-channel DNA microarray data were bioinformatically analyzed by BRB ArrayTools and IPA Software. Obtained were fifty-six differentially expressed genes involved in substance and energy metabolisms with the expression fold more than 2, including 11 genes up-regulated and 45 genes down-regulated. Of them, genes correlated to lipid metabolism included CRLS1, LRP11, FUT9, GPCPD1, PIGL, SULT1A4, B3GNT1, ST8SIA4, and ACADVL, mainly involved in the metabolic processes of fatty acid, cholesterol, phospholipids, and glycolipid. Genes correlated to protein metabolism included ASRGL1, AARSD1, EBNA1BP2, PUM2, MRPL52, C120RF65, PSMB8, PSME2, UBA7, RNF11, FBXO44, ZFYVE26, CHMP2A, SSR4, SNX4, RAB3B, RABL2A, GOLGA2, KDELR1, PHPT1, ACPP, PTPRF, CRKL, HDAC7, ADPRHL2, B3GNT1, ST8SIA4, DDOST, and FUT9, mainly involved in the biosynthesis processes of protein, ubiquitination, targeted transport and post-translation modification. Genes correlated to nucleic acid metabolism included DFFB, FLJ35220, TOP2A, SF3A3, CREB3, CRTC2, NR1D2, MED6, GTF2IRD1, C1ORF83, ZNF773, and ZMYND11, mainly involved in DNA replication and repair, transcription regulation. Genes correlated to carbohydrate metabolism included AGL, B3GNT1, FUT9, ST8SIA4, SULT1A4, DDOST, and PIGL, mainly involved in glucogen degradation and

Long Non-Coding RNAs in Metabolic Organs and Energy Homeostasis

Directory of Open Access Journals (Sweden)

Maude Giroud

2017-11-01

Full Text Available Single cell organisms can surprisingly exceed the number of human protein-coding genes, which are thus not at the origin of the complexity of an organism. In contrast, the relative amount of non-protein-coding sequences increases consistently with organismal complexity. Moreover, the mammalian transcriptome predominantly comprises non-(protein-coding RNAs (ncRNA, of which the long ncRNAs (lncRNAs constitute the most abundant part. lncRNAs are highly species- and tissue-specific with very versatile modes of action in accordance with their binding to a large spectrum of molecules and their diverse localization. lncRNAs are transcriptional regulators adding an additional regulatory layer in biological processes and pathophysiological conditions. Here, we review lncRNAs affecting metabolic organs with a focus on the liver, pancreas, skeletal muscle, cardiac muscle, brain, and adipose organ. In addition, we will discuss the impact of lncRNAs on metabolic diseases such as obesity and diabetes. In contrast to the substantial number of lncRNA loci in the human genome, the functionally characterized lncRNAs are just the tip of the iceberg. So far, our knowledge concerning lncRNAs in energy homeostasis is still in its infancy, meaning that the rest of the iceberg is a treasure chest yet to be discovered.

Constraints on Energy Intake in Fish: The Link between Diet Composition, Energy Metabolism, and Energy Intake in Rainbow Trout

Science.gov (United States)

Saravanan, Subramanian; Schrama, Johan W.; Figueiredo-Silva, A. Claudia; Kaushik, Sadasivam J.; Verreth, Johan A. J.; Geurden, Inge

2012-01-01

The hypothesis was tested that fish fed to satiation with iso-energetic diets differing in macronutrient composition will have different digestible energy intakes (DEI) but similar total heat production. Four iso-energetic diets (2×2 factorial design) were formulated having a contrast in i) the ratio of protein to energy (P/E): high (HP/E) vs. low (LP/E) and ii) the type of non-protein energy (NPE) source: fat vs. carbohydrate which were iso-energetically exchanged. Triplicate groups (35 fish/tank) of rainbow trout were hand-fed each diet twice daily to satiation for 6 weeks under non-limiting water oxygen conditions. Feed intake (FI), DEI (kJ kg−0.8 d−1) and growth (g kg−0.8 d−1) of trout were affected by the interaction between P/E ratio and NPE source of the diet (Ptrout by ∼20%. The diet-induced differences in FI and DEI show that trout did not compensate for the dietary differences in digestible energy or digestible protein contents. Further, changes in body fat store and plasma glucose did not seem to exert a homeostatic feedback control on DEI. Independent of the diet composition, heat production of trout did not differ (P>0.05). Our data suggest that the control of DEI in trout might be a function of heat production, which in turn might reflect a physiological limit related with oxidative metabolism. PMID:22496852

Metabolic disruption in context: Clinical avenues for synergistic perturbations in energy homeostasis by endocrine disrupting chemicals.

Science.gov (United States)

Sargis, Robert M

2015-01-01

The global epidemic of metabolic disease is a clear and present danger to both individual and societal health. Understanding the myriad factors contributing to obesity and diabetes is essential for curbing their decades-long expansion. Emerging data implicate environmental endocrine disrupting chemicals (EDCs) in the pathogenesis of metabolic diseases such as obesity and diabetes. The phenylsulfamide fungicide and anti-fouling agent tolylfluanid (TF) was recently added to the list of EDCs promoting metabolic dysfunction. Dietary exposure to this novel metabolic disruptor promoted weight gain, increased adiposity, and glucose intolerance as well as systemic and cellular insulin resistance. Interestingly, the increase in body weight and adipose mass was not a consequence of increased food consumption; rather, it may have resulted from disruptions in diurnal patterns of energy intake, raising the possibility that EDCs may promote metabolic dysfunction through alterations in circadian rhythms. While these studies provide further evidence that EDCs may promote the development of obesity and diabetes, many questions remain regarding the clinical factors that modulate patient-specific consequences of EDC exposure, including the impact of genetics, diet, lifestyle, underlying disease, pharmacological treatments, and clinical states of fat redistribution. Currently, little is known regarding the impact of these factors on an individual's susceptibility to environmentally-mediated metabolic disruption. Advances in these areas will be critical for translating EDC science into the clinic to enable physicians to stratify an individual's risk of developing EDC-induced metabolic disease and to provide direction for treating exposed patients.

Environmental and self-sufficiency assessment of the energy metabolism of tourist hubs on Mediterranean Islands: The case of Menorca (Spain)

International Nuclear Information System (INIS)

Sanyé-Mengual, Esther; Romanos, Héctor; Molina, Catalina; Oliver, M. Antònia; Ruiz, Núria; Pérez, Marta; Carreras, David; Boada, Martí; Garcia-Orellana, Jordi; Duch, Jordi; Rieradevall, Joan

2014-01-01

Energy performance of island tourism has been analyzed in the literature. However, tourist services tend to concentrate in tourist hubs, especially where mass tourism predominates (e.g., Mediterranean), and the energy metabolism of these systems has not yet been assessed. The present paper models and estimates the energy metabolism of tourist hubs in the Menorca Island (Spain) by integrating social, geographical and environmental methods. Mobility (both external and internal) and consumption of lodging services were characterized through surveys to users (tourists) and business managers. An environmental assessment evaluated CO 2 emissions, and energy self-sufficiency potential was estimated via GIS data. The results indicate that, on average, a tourist consumes 4756 MJ with associated emissions of 277 kg of CO 2 per stay (20 days on average). Of all the energy flows, external mobility contributes the most to total emissions (77%). For every day spent in a tourist hub, a tourist consumes between 29 MJ and 93 MJ in lodging services, consumption that could be 100% satisfied by photovoltaic systems, and these systems would result in positive effects for the island. Sustainable tourism management might focus on promoting environmentally friendly transportation, energy efficient practices, and environmental communication through ecolabeling. - Highlights: • We modeled the entire energy metabolism of tourist hubs in islands. • Results showed that a tourist in Menorca consumes from 4000 to 6000 MJ per trip. • External mobility (trip to the island) accounts for 77% of the total CO 2 emissions. • Photovoltaic systems could provide enough power to achieve self-sufficiency. • Tourists at hotel hubs have higher energy consumption than other types of hubs

Berberine Regulated Lipid Metabolism in the Presence of C75, Compound C, and TOFA in Breast Cancer Cell Line MCF-7.

Science.gov (United States)

Tan, Wen; Zhong, Zhangfeng; Wang, Shengpeng; Suo, Zhanwei; Yang, Xian; Hu, Xiaodong; Wang, Yitao

2015-01-01

Berberine interfering with cancer reprogramming metabolism was confirmed in our previous study. Lipid metabolism and mitochondrial function were also the core parts in reprogramming metabolism. In the presence of some energy-related inhibitors, including C75, compound C, and TOFA, the discrete roles of berberine in lipid metabolism and mitochondrial function were elucidated. An altered lipid metabolism induced by berberine was observed under the inhibition of FASN, AMPK, and ACC in breast cancer cell MCF-7. And the reversion of berberine-induced lipid suppression indicated that ACC inhibition might be involved in that process instead of FASN inhibition. A robust apoptosis induced by berberine even under the inhibition of AMPK and lipid synthesis was also indicated. Finally, mitochondrial function regulation under the inhibition of AMPK and ACC might be in an ACL-independent manner. Undoubtedly, the detailed mechanisms of berberine interfering with lipid metabolism and mitochondrial function combined with energy-related inhibitors need further investigation, including the potential compensatory mechanisms for ATP production and the upregulation of ACL.

Berberine Regulated Lipid Metabolism in the Presence of C75, Compound C, and TOFA in Breast Cancer Cell Line MCF-7

Directory of Open Access Journals (Sweden)

Wen Tan

2015-01-01

Full Text Available Berberine interfering with cancer reprogramming metabolism was confirmed in our previous study. Lipid metabolism and mitochondrial function were also the core parts in reprogramming metabolism. In the presence of some energy-related inhibitors, including C75, compound C, and TOFA, the discrete roles of berberine in lipid metabolism and mitochondrial function were elucidated. An altered lipid metabolism induced by berberine was observed under the inhibition of FASN, AMPK, and ACC in breast cancer cell MCF-7. And the reversion of berberine-induced lipid suppression indicated that ACC inhibition might be involved in that process instead of FASN inhibition. A robust apoptosis induced by berberine even under the inhibition of AMPK and lipid synthesis was also indicated. Finally, mitochondrial function regulation under the inhibition of AMPK and ACC might be in an ACL-independent manner. Undoubtedly, the detailed mechanisms of berberine interfering with lipid metabolism and mitochondrial function combined with energy-related inhibitors need further investigation, including the potential compensatory mechanisms for ATP production and the upregulation of ACL.

The effects of partial defeathering on energy metabolism in the laying fowl.