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Sample records for impairs energy metabolism

  1. Energy Metabolism Impairment in Migraine.

    Science.gov (United States)

    Cevoli, Sabina; Favoni, Valentina; Cortelli, Pietro

    2018-06-22

    Migraine is a common disabling neurological disorder which is characterised by recurring headache associated with a variety of sensory and autonomic symptoms. The pathophysiology of migraine remains not entirely understood, although many mechanisms involving the central and peripheral nervous system are now becoming clear. In particular, it is widely accepted that migraine is associated with energy metabolic impairment of the brain. The purpose of this review is to present an update overview of the energy metabolism involvement in the migraine pathophysiology. Several biochemical, morphological and magnetic resonance spectroscopy studies have confirmed the presence of energy production deficiency together with an increment of energy consumption in migraine patients. An increment of energy demand over a certain threshold create metabolic and biochemical preconditions for the onset of the migraine attack. The defect of oxidative energy metabolism in migraine is generalized. It remains to be determined if the mitochondrial deficit in migraine is primary or secondary. Riboflavin and Co-Enzyme Q10, both physiologically implicated in mitochondrial respiratory chain functioning, are effective in migraine prophylaxis, supporting the hypothesis that improving brain energy metabolism may reduce the susceptibility to migraine. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. 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...

  3. 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.

  4. 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

  5. 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...

  6. Epilepsy and astrocyte energy metabolism.

    Science.gov (United States)

    Boison, Detlev; Steinhäuser, Christian

    2018-06-01

    Epilepsy is a complex neurological syndrome characterized by neuronal hyperexcitability and sudden, synchronized electrical discharges that can manifest as seizures. It is now increasingly recognized that impaired astrocyte function and energy homeostasis play key roles in the pathogenesis of epilepsy. Excessive neuronal discharges can only happen, if adequate energy sources are made available to neurons. Conversely, energy depletion during seizures is an endogenous mechanism of seizure termination. Astrocytes control neuronal energy homeostasis through neurometabolic coupling. In this review, we will discuss how astrocyte dysfunction in epilepsy leads to distortion of key metabolic and biochemical mechanisms. Dysfunctional glutamate metabolism in astrocytes can directly contribute to neuronal hyperexcitability. Closure of astrocyte intercellular gap junction coupling as observed early during epileptogenesis limits activity-dependent trafficking of energy metabolites, but also impairs clearance of the extracellular space from accumulation of K + and glutamate. Dysfunctional astrocytes also increase the metabolism of adenosine, a metabolic product of ATP degradation that broadly inhibits energy-consuming processes as an evolutionary adaptation to conserve energy. Due to the critical role of astroglial energy homeostasis in the control of neuronal excitability, metabolic therapeutic approaches that prevent the utilization of glucose might represent a potent antiepileptic strategy. In particular, high fat low carbohydrate "ketogenic diets" as well as inhibitors of glycolysis and lactate metabolism are of growing interest for the therapy of epilepsy. © 2017 Wiley Periodicals, Inc.

  7. Perinatal exposure of mice to the pesticide DDT impairs energy expenditure and metabolism in adult female offspring.

    Directory of Open Access Journals (Sweden)

    Michele La Merrill

    Full Text Available Dichlorodiphenyltrichloroethane (DDT has been used extensively to control malaria, typhus, body lice and bubonic plague worldwide, until countries began restricting its use in the 1970s. Its use in malaria control continues in some countries according to recommendation by the World Health Organization. Individuals exposed to elevated levels of DDT and its metabolite dichlorodiphenyldichloroethylene (DDE have an increased prevalence of diabetes and insulin resistance. Here we hypothesize that perinatal exposure to DDT disrupts metabolic programming leading to impaired metabolism in adult offspring. To test this, we administered DDT to C57BL/6J mice from gestational day 11.5 to postnatal day 5 and studied their metabolic phenotype at several ages up to nine months. Perinatal DDT exposure reduced core body temperature, impaired cold tolerance, decreased energy expenditure, and produced a transient early-life increase in body fat in female offspring. When challenged with a high fat diet for 12 weeks in adulthood, female offspring perinatally exposed to DDT developed glucose intolerance, hyperinsulinemia, dyslipidemia, and altered bile acid metabolism. Perinatal DDT exposure combined with high fat feeding in adulthood further impaired thermogenesis as evidenced by reductions in core temperature and in the expression of numerous RNA that promote thermogenesis and substrate utilization in the brown adipose tissue of adult female mice. These observations suggest that perinatal DDT exposure impairs thermogenesis and the metabolism of carbohydrates and lipids which may increase susceptibility to the metabolic syndrome in adult female offspring.

  8. Perinatal Exposure of Mice to the Pesticide DDT Impairs Energy Expenditure and Metabolism in Adult Female Offspring

    Science.gov (United States)

    La Merrill, Michele; Karey, Emma; Moshier, Erin; Lindtner, Claudia; La Frano, Michael R.; Newman, John W.; Buettner, Christoph

    2014-01-01

    Dichlorodiphenyltrichloroethane (DDT) has been used extensively to control malaria, typhus, body lice and bubonic plague worldwide, until countries began restricting its use in the 1970s. Its use in malaria control continues in some countries according to recommendation by the World Health Organization. Individuals exposed to elevated levels of DDT and its metabolite dichlorodiphenyldichloroethylene (DDE) have an increased prevalence of diabetes and insulin resistance. Here we hypothesize that perinatal exposure to DDT disrupts metabolic programming leading to impaired metabolism in adult offspring. To test this, we administered DDT to C57BL/6J mice from gestational day 11.5 to postnatal day 5 and studied their metabolic phenotype at several ages up to nine months. Perinatal DDT exposure reduced core body temperature, impaired cold tolerance, decreased energy expenditure, and produced a transient early-life increase in body fat in female offspring. When challenged with a high fat diet for 12 weeks in adulthood, female offspring perinatally exposed to DDT developed glucose intolerance, hyperinsulinemia, dyslipidemia, and altered bile acid metabolism. Perinatal DDT exposure combined with high fat feeding in adulthood further impaired thermogenesis as evidenced by reductions in core temperature and in the expression of numerous RNA that promote thermogenesis and substrate utilization in the brown adipose tissue of adult female mice. These observations suggest that perinatal DDT exposure impairs thermogenesis and the metabolism of carbohydrates and lipids which may increase susceptibility to the metabolic syndrome in adult female offspring. PMID:25076055

  9. Recycling energy to restore impaired ankle function during human walking.

    Directory of Open Access Journals (Sweden)

    Steven H Collins

    Full Text Available BACKGROUND: Humans normally dissipate significant energy during walking, largely at the transitions between steps. The ankle then acts to restore energy during push-off, which may be the reason that ankle impairment nearly always leads to poorer walking economy. The replacement of lost energy is necessary for steady gait, in which mechanical energy is constant on average, external dissipation is negligible, and no net work is performed over a stride. However, dissipation and replacement by muscles might not be necessary if energy were instead captured and reused by an assistive device. METHODOLOGY/PRINCIPAL FINDINGS: We developed a microprocessor-controlled artificial foot that captures some of the energy that is normally dissipated by the leg and "recycles" it as positive ankle work. In tests on subjects walking with an artificially-impaired ankle, a conventional prosthesis reduced ankle push-off work and increased net metabolic energy expenditure by 23% compared to normal walking. Energy recycling restored ankle push-off to normal and reduced the net metabolic energy penalty to 14%. CONCLUSIONS/SIGNIFICANCE: These results suggest that reduced ankle push-off contributes to the increased metabolic energy expenditure accompanying ankle impairments, and demonstrate that energy recycling can be used to reduce such cost.

  10. 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.

  11. Cerebral energy metabolism during induced mitochondrial dysfunction

    DEFF Research Database (Denmark)

    Nielsen, T H; Bindslev, TT; Pedersen, S M

    2013-01-01

    In patients with traumatic brain injury as well as stroke, impaired cerebral oxidative energy metabolism may be an important factor contributing to the ultimate degree of tissue damage. We hypothesize that mitochondrial dysfunction can be diagnosed bedside by comparing the simultaneous changes...... in brain tissue oxygen tension (PbtO(2)) and cerebral cytoplasmatic redox state. The study describes cerebral energy metabolism during mitochondrial dysfunction induced by sevoflurane in piglets....

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. Exercise counteracts aging-related memory impairment: a potential role for the astrocytic metabolic shuttle

    Directory of Open Access Journals (Sweden)

    Sheng-Feng eTsai

    2016-03-01

    Full Text Available Age-related cognitive impairment has become one of the most common health threats in many countries. The biological substrate of cognition is the interconnection of neurons to form complex information processing networks. Experience-based alterations in the activities of these information processing networks lead to neuroadaptation, which is physically represented at the cellular level as synaptic plasticity. Although synaptic plasticity is known to be affected by aging, the underlying molecular mechanisms are not well described. Astrocytes, a glial cell type that is infrequently investigated in cognitive science, have emerged as energy suppliers which are necessary for meeting the abundant energy demand resulting from glutamatergic synaptic activity. Moreover, the concerted action of an astrocyte-neuron metabolic shuttle is essential for cognitive function; whereas, energetic incoordination between astrocytes and neurons may contribute to cognitive impairment. Whether altered function of the astrocyte-neuron metabolic shuttle links aging to reduced synaptic plasticity is unexplored. However, accumulated evidence documents significant beneficial effects of long-term, regular exercise on cognition and synaptic plasticity. Furthermore, exercise increases the effectiveness of astrocyte-neuron metabolic shuttle by upregulation of astrocytic lactate transporter levels. This review summarizes previous findings related to the neuronal activity-dependent astrocyte-neuron metabolic shuttle. Moreover, we discuss how aging and exercise may shape the astrocyte-neuron metabolic shuttle in cognition-associated brain areas.

  18. Effects of Insulin on Brain Glucose Metabolism in Impaired Glucose Tolerance

    Science.gov (United States)

    Hirvonen, Jussi; Virtanen, Kirsi A.; Nummenmaa, Lauri; Hannukainen, Jarna C.; Honka, Miikka-Juhani; Bucci, Marco; Nesterov, Sergey V.; Parkkola, Riitta; Rinne, Juha; Iozzo, Patricia; Nuutila, Pirjo

    2011-01-01

    OBJECTIVE Insulin stimulates brain glucose metabolism, but this effect of insulin is already maximal at fasting concentrations in healthy subjects. It is not known whether insulin is able to stimulate glucose metabolism above fasting concentrations in patients with impaired glucose tolerance. RESEARCH DESIGN AND METHODS We studied the effects of insulin on brain glucose metabolism and cerebral blood flow in 13 patients with impaired glucose tolerance and nine healthy subjects using positron emission tomography (PET). All subjects underwent PET with both [18F]fluorodeoxyglucose (for brain glucose metabolism) and [15O]H2O (for cerebral blood flow) in two separate conditions (in the fasting state and during a euglycemic-hyperinsulinemic clamp). Arterial blood samples were acquired during the PET scans to allow fully quantitative modeling. RESULTS The hyperinsulinemic clamp increased brain glucose metabolism only in patients with impaired glucose tolerance (whole brain: +18%, P = 0.001) but not in healthy subjects (whole brain: +3.9%, P = 0.373). The hyperinsulinemic clamp did not alter cerebral blood flow in either group. CONCLUSIONS We found that insulin stimulates brain glucose metabolism at physiological postprandial levels in patients with impaired glucose tolerance but not in healthy subjects. These results suggest that insulin stimulation of brain glucose metabolism is maximal at fasting concentrations in healthy subjects but not in patients with impaired glucose tolerance. PMID:21270256

  19. 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

  20. 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.

  1. 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.

  2. Skeletal muscle proteomic signature and metabolic impairment in pulmonary hypertension.

    Science.gov (United States)

    Malenfant, Simon; Potus, François; Fournier, Frédéric; Breuils-Bonnet, Sandra; Pflieger, Aude; Bourassa, Sylvie; Tremblay, Ève; Nehmé, Benjamin; Droit, Arnaud; Bonnet, Sébastien; Provencher, Steeve

    2015-05-01

    Exercise limitation comes from a close interaction between cardiovascular and skeletal muscle impairments. To better understand the implication of possible peripheral oxidative metabolism dysfunction, we studied the proteomic signature of skeletal muscle in pulmonary arterial hypertension (PAH). Eight idiopathic PAH patients and eight matched healthy sedentary subjects were evaluated for exercise capacity, skeletal muscle proteomic profile, metabolism, and mitochondrial function. Skeletal muscle proteins were extracted, and fractioned peptides were tagged using an iTRAQ protocol. Proteomic analyses have documented a total of 9 downregulated proteins in PAH skeletal muscles and 10 upregulated proteins compared to healthy subjects. Most of the downregulated proteins were related to mitochondrial structure and function. Focusing on skeletal muscle metabolism and mitochondrial health, PAH patients presented a decreased expression of oxidative enzymes (pyruvate dehydrogenase, p metabolism in PAH skeletal muscles. We provide evidences that impaired mitochondrial and metabolic functions found in the lungs and the right ventricle are also present in skeletal muscles of patients. • Proteomic and metabolic analysis show abnormal oxidative metabolism in PAH skeletal muscle. • EM of PAH patients reveals abnormal mitochondrial structure and distribution. • Abnormal mitochondrial health and function contribute to exercise impairments of PAH. • PAH may be considered a vascular affliction of heart and lungs with major impact on peripheral muscles.

  3. 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

  4. Metabolic Profiling of Impaired Cognitive Function in Patients Receiving Dialysis

    OpenAIRE

    Kurella Tamura, Manjula; Chertow, Glenn M.; Depner, Thomas A.; Nissenson, Allen R.; Schiller, Brigitte; Mehta, Ravindra L.; Liu, Sai; Sirich, Tammy L.

    2016-01-01

    Retention of uremic metabolites is a proposed cause of cognitive impairment in patients with ESRD. We used metabolic profiling to identify and validate uremic metabolites associated with impairment in executive function in two cohorts of patients receiving maintenance dialysis. We performed metabolic profiling using liquid chromatography/mass spectrometry applied to predialysis plasma samples from a discovery cohort of 141 patients and an independent replication cohort of 180 patients partici...

  5. Association of metabolic syndrome and 25-hydroxyvitamin D with cognitive impairment among elderly Koreans.

    Science.gov (United States)

    Lee, Eun Young; Lee, Su Jin; Kim, Kyoung Min; Yun, Young Mi; Song, Bo Mi; Kim, Jong Eun; Kim, Hyeon Chang; Rhee, Yumie; Youm, Yoosik; Kim, Chang Oh

    2017-07-01

    Metabolic syndrome and vitamin D deficiency are prevalent in older adults, and are considered risk factors for cognitive impairment. We investigated the combined effects of MetS and serum 25-hydroxyvitamin D (25[OH]D) levels on cognitive function in older adults. We studied 2940 participants aged ≥65 years from the Korean Urban Rural Elderly cohort study. Metabolic syndrome was defined according to the updated Adult Treatment Panel III criteria. Serum 25(OH)D levels were categorized into four groups: metabolic syndrome prevalence and lower serum 25(OH)D levels than those without cognitive impairment. In univariate analysis, both metabolic syndrome and low 25(OH)D levels were associated with cognitive impairment. These associations remained unchanged after adjusting for potential confounders including age, sex, season and education. In addition, participants with metabolic syndrome and low 25(OH)D had significantly increased odds for cognitive impairment (odds ratio 3.06, 95% CI 1.61-5.80) when compared with those with no metabolic syndrome and high 25(OH)D. Metabolic syndrome was associated with cognitive impairment, and this risk was synergistically increased when metabolic syndrome was combined with low 25(OH)D. A focus on individuals with metabolic syndrome and low 25(OH)D might be helpful to identify older adults who are at risk of cognitive impairment. Geriatr Gerontol Int 2017; 17: 1069-1075. © 2016 Japan Geriatrics Society.

  6. Systemic Metabolic Impairment and Lung Injury Following Acrolein Inhalation

    Science.gov (United States)

    A single ozone exposure causes pulmonary injury and systemic metabolic alterations through neuronal and hypothalamus pituitary adrenal axis activation. Metabolically impaired Goto Kakizaki (GK) rats with non-obese type-2 diabetes are more sensitive to ozone induced changes than h...

  7. 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.

  8. Impaired glucose metabolism in HIV-infected pregnant women: a retrospective analysis.

    LENUS (Irish Health Repository)

    Moore, Rebecca

    2015-05-20

    Metabolic complications including diabetes mellitus have been increasingly recognised in HIV-infected individuals since the introduction of antiretroviral therapy, particularly protease inhibitors (PIs). Pregnancy is also a risk factor for impaired glucose metabolism, and previous studies have given conflicting results regarding the contribution of PIs to impaired glucose tolerance (IGT) and gestational diabetes mellitus (GDM) in pregnant HIV-infected women.

  9. Brain Ceramide Metabolism in the Control of Energy Balance

    Directory of Open Access Journals (Sweden)

    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.

  10. Molecular Basis of Impaired Glycogen Metabolism during Ischemic Stroke and Hypoxia

    Science.gov (United States)

    Hossain, Mohammed Iqbal; Roulston, Carli Lorraine; Stapleton, David Ian

    2014-01-01

    Background Ischemic stroke is the combinatorial effect of many pathological processes including the loss of energy supplies, excessive intracellular calcium accumulation, oxidative stress, and inflammatory responses. The brain's ability to maintain energy demand through this process involves metabolism of glycogen, which is critical for release of stored glucose. However, regulation of glycogen metabolism in ischemic stroke remains unknown. In the present study, we investigate the role and regulation of glycogen metabolizing enzymes and their effects on the fate of glycogen during ischemic stroke. Results Ischemic stroke was induced in rats by peri-vascular application of the vasoconstrictor endothelin-1 and forebrains were collected at 1, 3, 6 and 24 hours post-stroke. Glycogen levels and the expression and activity of enzymes involved in glycogen metabolism were analyzed. We found elevated glycogen levels in the ipsilateral hemispheres compared with contralateral hemispheres at 6 and 24 hours (25% and 39% increase respectively; PGlycogen synthase activity and glycogen branching enzyme expression were found to be similar between the ipsilateral, contralateral, and sham control hemispheres. In contrast, the rate-limiting enzyme for glycogen breakdown, glycogen phosphorylase, had 58% lower activity (Pglycogen debranching enzyme expression 24 hours post-stroke was 77% (Pglycogen phosphorylase activity and increased glycogen accumulation but did not alter glycogen synthase activity. Furthermore, elevated glycogen levels provided metabolic support to astrocytes during hypoxia. Conclusion Our study has identified that glycogen breakdown is impaired during ischemic stroke, the molecular basis of which includes reduced glycogen debranching enzyme expression level together with reduced glycogen phosphorylase and PKA activity. PMID:24858129

  11. 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...

  12. Hypocapnic but not metabolic alkalosis impairs alveolar fluid reabsorption.

    Science.gov (United States)

    Myrianthefs, Pavlos M; Briva, Arturo; Lecuona, Emilia; Dumasius, Vidas; Rutschman, David H; Ridge, Karen M; Baltopoulos, George J; Sznajder, Jacob Iasha

    2005-06-01

    Acid-base disturbances, such as metabolic or respiratory alkalosis, are relatively common in critically ill patients. We examined the effects of alkalosis (hypocapnic or metabolic alkalosis) on alveolar fluid reabsorption in the isolated and continuously perfused rat lung model. We found that alveolar fluid reabsorption after 1 hour was impaired by low levels of CO2 partial pressure (PCO2; 10 and 20 mm Hg) independent of pH levels (7.7 or 7.4). In addition, PCO2 higher than 30 mm Hg or metabolic alkalosis did not have an effect on this process. The hypocapnia-mediated decrease of alveolar fluid reabsorption was associated with decreased Na,K-ATPase activity and protein abundance at the basolateral membranes of distal airspaces. The effect of low PCO2 on alveolar fluid reabsorption was reversible because clearance normalized after correcting the PCO2 back to normal levels. These data suggest that hypocapnic but not metabolic alkalosis impairs alveolar fluid reabsorption. Conceivably, correction of hypocapnic alkalosis in critically ill patients may contribute to the normalization of lung ability to clear edema.

  13. Metabolic Profiling of Impaired Cognitive Function in Patients Receiving Dialysis.

    Science.gov (United States)

    Kurella Tamura, Manjula; Chertow, Glenn M; Depner, Thomas A; Nissenson, Allen R; Schiller, Brigitte; Mehta, Ravindra L; Liu, Sai; Sirich, Tammy L

    2016-12-01

    Retention of uremic metabolites is a proposed cause of cognitive impairment in patients with ESRD. We used metabolic profiling to identify and validate uremic metabolites associated with impairment in executive function in two cohorts of patients receiving maintenance dialysis. We performed metabolic profiling using liquid chromatography/mass spectrometry applied to predialysis plasma samples from a discovery cohort of 141 patients and an independent replication cohort of 180 patients participating in a trial of frequent hemodialysis. We assessed executive function with the Trail Making Test Part B and the Digit Symbol Substitution test. Impaired executive function was defined as a score ≥2 SDs below normative values. Four metabolites-4-hydroxyphenylacetate, phenylacetylglutamine, hippurate, and prolyl-hydroxyproline-were associated with impaired executive function at the false-detection rate significance threshold. After adjustment for demographic and clinical characteristics, the associations remained statistically significant: relative risk 1.16 (95% confidence interval [95% CI], 1.03 to 1.32), 1.39 (95% CI, 1.13 to 1.71), 1.24 (95% CI, 1.03 to 1.50), and 1.20 (95% CI, 1.05 to 1.38) for each SD increase in 4-hydroxyphenylacetate, phenylacetylglutamine, hippurate, and prolyl-hydroxyproline, respectively. The association between 4-hydroxyphenylacetate and impaired executive function was replicated in the second cohort (relative risk 1.12; 95% CI, 1.02 to 1.23), whereas the associations for phenylacetylglutamine, hippurate, and prolyl-hydroxyproline did not reach statistical significance in this cohort. In summary, four metabolites related to phenylalanine, benzoate, and glutamate metabolism may be markers of cognitive impairment in patients receiving maintenance dialysis. Copyright © 2016 by the American Society of Nephrology.

  14. 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

  15. 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...

  16. Astrocytes and energy metabolism.

    Science.gov (United States)

    Prebil, Mateja; Jensen, Jørgen; Zorec, Robert; Kreft, Marko

    2011-05-01

    Astrocytes are glial cells, which play a significant role in a number of processes, including the brain energy metabolism. Their anatomical position between blood vessels and neurons make them an interface for effective glucose uptake from blood. After entering astrocytes, glucose can be involved in different metabolic pathways, e.g. in glycogen production. Glycogen in the brain is localized mainly in astrocytes and is an important energy source in hypoxic conditions and normal brain functioning. The portion of glucose metabolized into glycogen molecules in astrocytes is as high as 40%. It is thought that the release of gliotransmitters (such as glutamate, neuroactive peptides and ATP) into the extracellular space by regulated exocytosis supports a significant part of communication between astrocytes and neurons. On the other hand, neurotransmitter action on astrocytes has a significant role in brain energy metabolism. Therefore, understanding the astrocytes energy metabolism may help understanding neuron-astrocyte interactions.

  17. Skeletal muscle metabolism is impaired during exercise in glycogen storage disease type III

    DEFF Research Database (Denmark)

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

    2015-01-01

    /kg/min (p = 0.024). Fructose ingestion improved exercise tolerance in the patients. CONCLUSION: Similar to patients with McArdle disease, in whom muscle glycogenolysis is also impaired, GSDIIIa is associated with a reduced skeletal muscle oxidation of carbohydrates and a compensatory increase in fatty acid......OBJECTIVE: Glycogen storage disease type IIIa (GSDIIIa) is classically regarded as a glycogenosis with fixed weakness, but we hypothesized that exercise intolerance in GSDIIIa is related to muscle energy failure and that oral fructose ingestion could improve exercise tolerance in this metabolic...... myopathy. METHODS: We challenged metabolism with cycle-ergometer exercise and measured substrate turnover and oxidation rates using stable isotope methodology and indirect calorimetry in 3 patients and 6 age-matched controls on 1 day, and examined the effect of fructose ingestion on exercise tolerance...

  18. Dementia with impaired glucose metabolism in late onset metachromatic leukodystrophy

    DEFF Research Database (Denmark)

    Johannsen, P.; Ehlers, L.; Hansen, Hans Jacob

    2001-01-01

    and attention deficits with a slow psychomotor speed. MR brain imaging displayed confluent hyperintensities of periventricular and subcortical white matter. Low levels of arylsulfatase A confirmed the diagnosis. Impaired cortical glucose metabolism especially of the medial temporal and frontal cortices...... was observed using positron emission tomography and fluor-18-labeled fluorodesoxyglucose. The neuropsychological deficits are related to the location of deficits in glucose metabolism....

  19. 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.

  20. 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.

  1. Cerebral Metabolic Differences Associated with Cognitive Impairment in Parkinson's Disease.

    Directory of Open Access Journals (Sweden)

    Yilin Tang

    Full Text Available To characterize cerebral glucose metabolism associated with different cognitive states in Parkinson's disease (PD using 18F-fluorodeoxyglucose (FDG and Positron Emission Tomography (PET.Three groups of patients were recruited in this study including PD patients with dementia (PDD; n = 10, with mild cognitive impairment (PD-MCI; n = 20, and with no cognitive impairment (PD-NC; n = 30. The groups were matched for age, sex, education, disease duration, motor disability, levodopa equivalent dose and Geriatric Depression Rating Scale (GDS score. All subjects underwent a FDG-PET study. Maps of regional metabolism in the three groups were compared using statistical parametric mapping (SPM5.PD-MCI patients exhibited limited areas of hypometabolism in the frontal, temporal and parahippocampal gyrus compared with the PD-NC patients (p < 0.01. PDD patients had bilateral areas of hypometabolism in the frontal and posterior parietal-occipital lobes compared with PD-MCI patients (p < 0.01, and exhibited greater metabolic reductions in comparison with PD-NC patients (p < 0.01.Compared with PD-NC patients, hypometabolism was much higher in the PDD patients than in PD-MCI patients, mainly in the posterior cortical areas. The result might suggest an association between posterior cortical hypometabolism and more severe cognitive impairment. PD-MCI might be important for early targeted therapeutic intervention and disease modification.

  2. 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.

  3. Cofilin/Twinstar phosphorylation levels increase in response to impaired coenzyme a metabolism.

    Directory of Open Access Journals (Sweden)

    Katarzyna Siudeja

    Full Text Available Coenzyme A (CoA is a pantothenic acid-derived metabolite essential for many fundamental cellular processes including energy, lipid and amino acid metabolism. Pantothenate kinase (PANK, which catalyses the first step in the conversion of pantothenic acid to CoA, has been associated with a rare neurodegenerative disorder PKAN. However, the consequences of impaired PANK activity are poorly understood. Here we use Drosophila and human neuronal cell cultures to show how PANK deficiency leads to abnormalities in F-actin organization. Cells with reduced PANK activity are characterized by abnormally high levels of phosphorylated cofilin, a conserved actin filament severing protein. The increased levels of phospho-cofilin coincide with morphological changes of PANK-deficient Drosophila S2 cells and human neuronal SHSY-5Y cells. The latter exhibit also markedly reduced ability to form neurites in culture--a process that is strongly dependent on actin remodeling. Our results reveal a novel and conserved link between a metabolic biosynthesis pathway, and regulation of cellular actin dynamics.

  4. 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.

  5. CARDIOVASCULAR AND METABOLIC IMPAIRMENT IN PATIENTS WITH OBSTRUCTIVE SLEEP APNEA

    Directory of Open Access Journals (Sweden)

    M. V. Gorbunova

    2018-01-01

    Full Text Available Since the moment when the obstructive nature of sleep apnea was first revealed, many new in-formation on this disease have been obtained. Now obstructive sleep apnea (OSA recognized as an  independent predictor of the development of impaired glucose  tolerance (insulin resistance, fasting hyperglycaemia, type 2  diabetes mellitus (DM2, resistant arterial hypertension, cardio- vascular death. The problem of identifying and treating patients with OSA is still actual. In real clinical practice, there is a need for an integrated approach to the diagnosis and therapy of comorbid OSA patients with metabolic impairment and cardiovascular  diseases.The aim of this review is to assess the clinical and  pathogenesis features of metabolic impaired, carbohydrate metabolism, basic metabolism, eating behavior, body weight fluctuations in patients with ob-structive sleep apnea syndrome. Methods. In our work, we used a retrospective analysis of pub-lished clinical research data of domestic and foreign authors  over the past 20 years. The review included studies with adequate  design from the standpoint of «good clinical practice» (GCP and  evidence-based medicine.The conclusion. According to modern  interpretation, obstructive sleep apnea is considered as an  independent disease that has its pathogenic mechanisms, clinical  and functional manifestations. There are several main causes of the effect of OSA on the metabolic component and the work of the cardiovascular system. Among them, intermittent hypoxemia,  endothelial dysfunction, fluctuations in intrathoracic pressure,  increased activity of the sympathetic nervous system, disturbance of the structure of sleep are leading. OSA is considered as a disease capable of disabling patients of working age, dramatically changing  the quality of life, leading to early mortality due to cardiovascular  disasters. Timely detection of clinical symptoms of OSA and the  strategy of early

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

    Directory of Open Access Journals (Sweden)

    Erica L. Underwood

    2016-01-01

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

  7. [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

  8. Systemic Inflammation and Lung Function Impairment in Morbidly Obese Subjects with the Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Astrid van Huisstede

    2013-01-01

    Full Text Available Background. Obesity and asthma are associated. There is a relationship between lung function impairment and the metabolic syndrome. Whether this relationship also exists in the morbidly obese patients is still unknown. Hypothesis. Low-grade systemic inflammation associated with the metabolic syndrome causes inflammation in the lungs and, hence, lung function impairment. Methods. This is cross-sectional study of morbidly obese patients undergoing preoperative screening for bariatric surgery. Metabolic syndrome was assessed according to the revised NCEP-ATP III criteria. Results. A total of 452 patients were included. Patients with the metabolic syndrome (n=293 had significantly higher blood monocyte (mean 5.3 versus 4.9, P=0.044 and eosinophil percentages (median 1.0 versus 0.8, P=0.002, while the total leukocyte count did not differ between the groups. The FEV1/FVC ratio was significantly lower in patients with the metabolic syndrome (76.7% versus 78.2%, P=0.032. Blood eosinophils were associated with FEV1/FVC ratio (adj. B −0.113, P=0.018. Conclusion. Although the difference in FEV1/FVC ratio between the groups is relatively small, in this cross-sectional study, and its clinical relevance may be limited, these data indicate that the presence of the metabolic syndrome may influence lung function impairment, through the induction of relative eosinophilia.

  9. MiADMSA reverses impaired mitochondrial energy metabolism and neuronal apoptotic cell death after arsenic exposure in rats

    Energy Technology Data Exchange (ETDEWEB)

    Dwivedi, Nidhi; Mehta, Ashish; Yadav, Abhishek [Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Gwalior-474 002 (India); Binukumar, B.K.; Gill, Kiran Dip [Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh-160 012 (India); Flora, Swaran J.S., E-mail: sjsflora@hotmail.com [Division of Pharmacology and Toxicology, Defence Research and Development Establishment, Gwalior-474 002 (India)

    2011-11-15

    Arsenicosis, due to contaminated drinking water, is a serious health hazard in terms of morbidity and mortality. Arsenic induced free radicals generated are known to cause cellular apoptosis through mitochondrial driven pathway. In the present study, we investigated the effect of arsenic interactions with various complexes of the electron transport chain and attempted to evaluate if there was any complex preference of arsenic that could trigger apoptosis. We also evaluated if chelation with monoisoamyl dimercaptosuccinic acid (MiADMSA) could reverse these detrimental effects. Our results indicate that arsenic exposure induced free radical generation in rat neuronal cells, which diminished mitochondrial potential and enzyme activities of all the complexes of the electron transport chain. Moreover, these complexes showed differential responses towards arsenic. These early events along with diminished ATP levels could be co-related with the later events of cytosolic migration of cytochrome c, altered bax/bcl{sub 2} ratio, and increased caspase 3 activity. Although MiADMSA could reverse most of these arsenic-induced altered variables to various extents, DNA damage remained unaffected. Our study for the first time demonstrates the differential effect of arsenic on the complexes leading to deficits in bioenergetics leading to apoptosis in rat brain. However, more in depth studies are warranted for better understanding of arsenic interactions with the mitochondria. -- Research highlights: Black-Right-Pointing-Pointer Arsenic impairs mitochondrial energy metabolism leading to neuronal apoptosis. Black-Right-Pointing-Pointer Arsenic differentially affects mitochondrial complexes, I - III and IV being more sensitive than complex II. Black-Right-Pointing-Pointer Arsenic-induced apoptosis initiates through ROS generation or impaired [Ca{sup 2+}]i homeostasis. Black-Right-Pointing-Pointer MiADMSA reverses arsenic toxicity via intracellular arsenic- chelation, antioxidant

  10. Impaired NAD+ Metabolism in Neuronal Dysfunction in Critical Conditions

    Directory of Open Access Journals (Sweden)

    A. V Salmina

    2008-01-01

    Full Text Available The present views of the pathogenesis of neuronal dysfunction in critical conditions are analyzed, by taking into account of impairments of cellular NAD+ metabolism, the activity of NAD+-converting enzymes, including ADP-ribosyl cyclase/CD38, the possibilities of developing new neuroprotective strategies. Key words: neuronal dysfunction, ADP-rybosyl cyclase/CD38, NAD+, critical condition.

  11. The energy metabolism of megacities

    International Nuclear Information System (INIS)

    Facchini, Angelo; Kennedy, Chris; Stewart, Iain; Mele, Renata

    2017-01-01

    Highlights: • Energy metabolism leads to a better management of energy use in megacities. • Insights on strategies to improve energy efficiency and reduce resource consumption. • We find a regionalization of energy flows and sectoral energy use. • Scaling law for energy Vs density suggests strategies for compact cities planning. • Supports development of models to reduce GHG emissions and increase resilience. - Abstract: Due to their sheer size and complexity, megacities are extreme examples in which both negative and positive aspects of urbanization co-exist and are amplified. Especially in emerging countries they are becoming the dominant paradigm of the future urbanization, representing a sustainability challenge both from the point of view of energy and resource consumption, and from the point of view of climate change adaptation and mitigation. In this paper we compare the energy metabolism in 27 of the world’s megacities including details of mobile and stationary energy consumption patterns, fuels used, as well as end-use patterns and electricity generation mix. Our results show that per capita total energy consumption scales with urban population density according to a power law characterized by the universal −3/4 scaling, pointing out that compact cities are more energy efficient with respect to dispersed cities. By comparing energy sources and sectoral end use, also focusing on electricity use and generation source, we found a significant regionalization of energy metabolism, and we discuss the implication for resilience, infrastructure planning, GHG emissions, and policies for infrastructure decarbonization. The comparison of the energy metabolism can lead to a more appropriate management of energy use patterns and electricity generation mix in megacities, giving insights on strategies to improve urban energy efficiency and reducing environmental pressure of megacities.

  12. Restoration of Impaired Metabolic Energy Balance (ATP Pool and Tube Formation Potential of Endothelial Cells under “high glucose”, Diabetic Conditions by the Bioinorganic Polymer Polyphosphate

    Directory of Open Access Journals (Sweden)

    Xiaohong Wang

    2017-11-01

    Full Text Available Micro-vascularization is a fast, energy-dependent process that is compromised by elevated glucose concentrations such as in diabetes mellitus disease. Here, we studied the effect of the physiological bioinorganic polymer, polyphosphate (polyP, on the reduced ATP content and impaired function of endothelial cells cultivated under “high glucose” (35 mM diabetes mellitus conditions concentrations. This high-energy biopolymer has been shown to provide a source of metabolic energy, stored in its phosphoanhydride bonds. We show that exposure of human umbilical vein endothelial cells (HUVEC cells to “high glucose” levels results in reduced cell viability, increased apoptotic cell death, and a decline in intracellular ATP level. As a consequence, the ability of HUVEC cells to form tube-like structures in the in vitro cell tube formation assay was almost completely abolished under “high glucose” conditions. Those cells were grown onto a physiological collagen scaffold (collagen/basement membrane extract. We demonstrate that these adverse effects of increased glucose levels can be reversed by administration of polyP to almost normal values. Using Na-polyP, complexed in a stoichiometric (molar ratio to Ca2+ ions and in the physiological concentration range between 30 and 300 µM, an almost complete restoration of the reduced ATP pool of cells exposed to “high glucose” was found, as well as a normalization of the number of apoptotic cells and energy-dependent tube formation. It is concluded that the adverse effects on endothelial cells caused by the metabolic energy imbalance at elevated glucose concentrations can be counterbalanced by polyP, potentially opening new strategies for treatment of the micro-vascular complications in diabetic patients.

  13. Energy metabolism in the liver.

    Science.gov (United States)

    Rui, Liangyou

    2014-01-01

    The liver is an essential metabolic organ, and its metabolic function is controlled by insulin and other metabolic hormones. Glucose is converted into pyruvate through glycolysis in the cytoplasm, and pyruvate is subsequently oxidized in the mitochondria to generate ATP through the TCA cycle and oxidative phosphorylation. In the fed state, glycolytic products are used to synthesize fatty acids through de novo lipogenesis. Long-chain fatty acids are incorporated into triacylglycerol, phospholipids, and/or cholesterol esters in hepatocytes. These complex lipids are stored in lipid droplets and membrane structures, or secreted into the circulation as very low-density lipoprotein particles. In the fasted state, the liver secretes glucose through both glycogenolysis and gluconeogenesis. During pronged fasting, hepatic gluconeogenesis is the primary source for endogenous glucose production. Fasting also promotes lipolysis in adipose tissue, resulting in release of nonesterified fatty acids which are converted into ketone bodies in hepatic mitochondria though β-oxidation and ketogenesis. Ketone bodies provide a metabolic fuel for extrahepatic tissues. Liver energy metabolism is tightly regulated by neuronal and hormonal signals. The sympathetic system stimulates, whereas the parasympathetic system suppresses, hepatic gluconeogenesis. Insulin stimulates glycolysis and lipogenesis but suppresses gluconeogenesis, and glucagon counteracts insulin action. Numerous transcription factors and coactivators, including CREB, FOXO1, ChREBP, SREBP, PGC-1α, and CRTC2, control the expression of the enzymes which catalyze key steps of metabolic pathways, thus controlling liver energy metabolism. Aberrant energy metabolism in the liver promotes insulin resistance, diabetes, and nonalcoholic fatty liver diseases. © 2014 American Physiological Society.

  14. Elevated 20-HETE impairs coronary collateral growth in metabolic syndrome via endothelial dysfunction.

    Science.gov (United States)

    Joseph, Gregory; Soler, Amanda; Hutcheson, Rebecca; Hunter, Ian; Bradford, Chastity; Hutcheson, Brenda; Gotlinger, Katherine H; Jiang, Houli; Falck, John R; Proctor, Spencer; Schwartzman, Michal Laniado; Rocic, Petra

    2017-03-01

    Coronary collateral growth (CCG) is impaired in metabolic syndrome (MetS). microRNA-145 (miR-145-Adv) delivery to our rat model of MetS (JCR) completely restored and neutrophil depletion significantly improved CCG. We determined whether low endogenous levels of miR-145 in MetS allowed for elevated production of 20-hydroxyeicosatetraenoic acid (20-HETE), which, in turn, resulted in excessive neutrophil accumulation and endothelial dysfunction leading to impaired CCG. Rats underwent 0-9 days of repetitive ischemia (RI). RI-induced cardiac CYP4F (neutrophil-specific 20-HETE synthase) expression and 20-HETE levels were increased (4-fold) in JCR vs. normal rats. miR-145-Adv and 20-HETE antagonists abolished and neutrophil depletion (blocking antibodies) reduced (~60%) RI-induced increases in CYP4F expression and 20-HETE production in JCR rats. Impaired CCG in JCR rats (collateral-dependent blood flow using microspheres) was completely restored by 20-HETE antagonists [collateral-dependent zone (CZ)/normal zone (NZ) flow ratio was 0.76 ± 0.07 in JCR + 20-SOLA, 0.84 ± 0.05 in JCR + 20-HEDGE vs. 0.11 ± 0.02 in JCR vs. 0.84 ± 0.03 in normal rats]. In JCR rats, elevated 20-HETE was associated with excessive expression of endothelial adhesion molecules and neutrophil infiltration, which were reversed by miR-145-Adv. Endothelium-dependent vasodilation of coronary arteries, endothelial nitric oxide synthase (eNOS) Ser1179 phosphorylation, eNOS-dependent NO ·- production and endothelial cell survival were compromised in JCR rats. These parameters of endothelial dysfunction were completely reversed by 20-HETE antagonism or miR-145-Adv delivery, whereas neutrophil depletion resulted in partial reversal (~70%). We conclude that low miR-145 in MetS allows for increased 20-HETE, mainly from neutrophils, which compromises endothelial cell survival and function leading to impaired CCG. 20-HETE antagonists could provide viable therapy for restoration of CCG in MetS. NEW & NOTEWORTHY

  15. 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.

  16. Intrahippocampal Administration of Amyloid-β1–42 Oligomers Acutely Impairs Spatial Working Memory, Insulin Signaling, and Hippocampal Metabolism

    Science.gov (United States)

    Pearson-Leary, Jiah; McNay, Ewan C.

    2017-01-01

    Increasing evidence suggests that abnormal brain accumulation of amyloid-β1–42 (Aβ1–42) oligomers plays a causal role in Alzheimer’s disease (AD), and in particular may cause the cognitive deficits that are the hallmark of AD. In vitro, Aβ1–42 oligomers impair insulin signaling and suppress neural functioning. We previously showed that endogenous insulin signaling is an obligatory component of normal hippocampal function, and that disrupting this signaling led to a rapid impairment of spatial working memory, while delivery of exogenous insulin to the hippocampus enhanced both memory and metabolism; diet-induced insulin resistance both impaired spatial memory and prevented insulin from increasing metabolism or cognitive function. Hence, we tested the hypothesis that Aβ1–42 oligomers could acutely impair hippocampal metabolic and cognitive processes in vivo in the rat. Our findings support this hypothesis: Aβ1–42 oligomers impaired spontaneous alternation behavior while preventing the task-associated dip in hippocampal ECF glucose observed in control animals. In addition, Aβ1–42 oligomers decreased plasma membrane translocation of the insulin-sensitive glucose transporter 4 (GluT4), and impaired insulin signaling as measured by phosphorylation of Akt. These data show in vivo that Aβ1–42 oligomers can rapidly impair hippocampal cognitive and metabolic processes, and provide support for the hypothesis that elevated Aβ1–42 leads to cognitive impairment via interference with hippocampal insulin signaling. PMID:22430529

  17. Long-Term Interrelationship between Brain Metabolism and Amyloid Deposition in Mild Cognitive Impairment

    DEFF Research Database (Denmark)

    Kemppainen, Nina; Joutsa, Juho; Johansson, Jarkko

    2015-01-01

    The aim of this longitudinal positron emission tomography (PET) study was to evaluate the interrelationship between brain metabolism and amyloid accumulation during the disease process from mild cognitive impairment (MCI) to Alzheimer's disease (AD). Nine MCI patients, who converted to AD between...... especially in the temporal-parietal regions in MCI compared to controls at baseline, and widely over the cortex at the 5-year follow-up. The reduction in metabolism during the follow-up was significant in the posterior brain regions. In addition, brain amyloid load was positively associated with metabolism...

  18. Cause of impaired carbohydrate metabolism in hyperthyroidism

    International Nuclear Information System (INIS)

    Foeldes, J.; Megyesi, K.; Koranyi, L.

    1984-01-01

    Hyperthyroidism (HT) affects glucose metabolism in various ways. The role of insulin, glucagon and growth-hormone (GH) was determined. After glucose loading the insulin response is weaker in HT than in euthyroid subjects. Enhanced degradation of insulin has been reported. It is suggested that in HT the serum insulin concentration declines at a slightly accelerated rate. In HT the deranged carbohydrate metabolism might be a consequence of altered tissue sensitivity to insulin. To elucidate this problem insulin receptors on erythrocytes obtained from hyperthyroid women were investigated. The maximal specific binding of 125 I-insulin to RBC of hyperthyroid patients was decreased and the analysis refers to a decreased receptor concentration in RBC. The nature of glucagon secretion and its influence on glucose metabolism in HT was investigated. The basal plasma glucagon is elevated in hyperthyroid patients. The suppression of glucagon secretion induced by an oral glucose loading was of significantly lesser degree in hyperthyroid patients than in controls. Applying the erythrocyte receptor assay a decreased specific binding of 125 I-glucagon to RBC of hyperthyroid patients has been found and data indicate a significantly less glucagon receptor concentration in thyrotoxicosis. Physiological elevations of serum GH levels led to a significant impairment of glucose metabolism. Beside the GH-RH and somatostatin, the dopaminergic neurotransmitter system participates in the regulation of GH secretion too. It has been demonstrated that after administration of the dopamine agonist l-dopa the GH response was weaker in HT than in controls. This indicates that in thyrotoxicosis the GH secretion can not be stimulated in such a degree as in euthyroidism. (author)

  19. Cause of impaired carbohydrate metabolism in hyperthyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Foeldes, J.; Megyesi, K.; Koranyi, L. (Semmelweis Orvostudomanyi Egyetem, Budapest (Hungary))

    1984-01-01

    Hyperthyroidism (HT) affects glucose metabolism in various ways. The role of insulin, glucagon and growth-hormone (GH) was determined. After glucose loading the insulin response is weaker in HT than in euthyroid subjects. Enhanced degradation of insulin has been reported. It is suggested that in HT the serum insulin concentration declines at a slightly accelerated rate. In HT the deranged carbohydrate metabolism might be a consequence of altered tissue sensitivity to insulin. To elucidate this problem insulin receptors on erythrocytes obtained from hyperthyroid women were investigated. The maximal specific binding of /sup 125/I-insulin to RBC of hyperthyroid patients was decreased and the analysis refers to a decreased receptor concentration in RBC. The nature of glucagon secretion and its influence on glucose metabolism in HT was investigated. The basal plasma glucagon is elevated in hyperthyroid patients. The suppression of glucagon secretion induced by an oral glucose loading was of significantly lesser degree in hyperthyroid patients than in controls. Applying the erythrocyte receptor assay a decreased specific binding of /sup 125/I-glucagon to RBC of hyperthyroid patients has been found and data indicate a significantly less glucagon receptor concentration in thyrotoxicosis. Physiological elevations of serum GH levels led to a significant impairment of glucose metabolism. Beside the GH-RH and somatostatin, the dopaminergic neurotransmitter system participates in the regulation of GH secretion too. It has been demonstrated that after administration of the dopamine agonist l-dopa the GH response was weaker in HT than in controls. This indicates that in thyrotoxicosis the GH secretion can not be stimulated in such a degree as in euthyroidism.

  20. 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.

  1. Exploration of Energy Metabolism in the Mouse Using Indirect Calorimetry: Measurement of Daily Energy Expenditure (DEE) and Basal Metabolic Rate (BMR).

    Science.gov (United States)

    Meyer, Carola W; Reitmeir, Peter; Tschöp, Matthias H

    2015-09-01

    Current comprehensive mouse metabolic phenotyping involves studying energy balance in cohorts of mice via indirect calorimetry, which determines heat release from changes in respiratory air composition. Here, we describe the measurement of daily energy expenditure (DEE) and basal metabolic rate (BMR) in mice. These well-defined metabolic descriptors serve as meaningful first-line read-outs for metabolic phenotyping and should be reported when exploring energy expenditure in mice. For further guidance, the issue of appropriate sample sizes and the frequency of sampling of metabolic measurements is also discussed. Copyright © 2015 John Wiley & Sons, Inc.

  2. 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.

  3. The Effect of Hippocampal Cognitive Impairment and XIAP on Glucose and Lipids Metabolism in Rats

    Directory of Open Access Journals (Sweden)

    Chunbo Xia

    2016-02-01

    Full Text Available Background/Aims: To investigate the effect of cognitive impairment and X-linked inhibitor of apoptosis protein (XIAP on glucolipid metabolism. Materials and Methods: β-amyloid (Aβ 1-42 was injected into the hippocampus of rats to establish a cognitive impairment model. Trans-activator of transcription (TAT-XIAP fusion protein (the TAT-XIAP group, PBS (the model group, or XIAP antisense oligonucleotides (the ASODN group was injected into the lateral ventricles of the rats to increase and decrease the activity of XIAP in the hippocampus. To determine the level of blood glucose and lipids, adenosine monophosphate-activated protein kinase (AMPK expression of liver and hipppocamual neuronal apoptosis. Results: The levels of FPG, TG, TC and LDL were significantly higher in the TAT-XIAP group, the model group and the ASODN group than in the blank group (P Conclusion: Cognitive impairment and hippocampal neuron apoptosis can cause glucose and lipids metabolic abnormalities, possibly by regulating gastrointestinal motility and AMPK expression in the liver. The changes in the function of XIAP, which is an anti-apoptotic protein in the hippocampus, may affect the metabolism of glucose and lipids.

  4. Energy Metabolism in the Liver

    Science.gov (United States)

    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, phospholipids, and cholesterol esters in hepatocytes, and these complex lipids are stored in lipid droplets and membrane structures, or secreted into the circulation as VLDL particles. In the fasted state, the liver secretes glucose through both breakdown of glycogen (glycogenolysis) and de novo glucose synthesis (gluconeogenesis). During pronged fasting, hepatic gluconeogenesis is the primary source of endogenous glucose production. Fasting also promotes lipolysis in adipose tissue to release nonesterified fatty acids which are converted into ketone bodies in the liver though mitochondrial β oxidation and ketogenesis. Ketone bodies provide a metabolic fuel for extrahepatic tissues. Liver metabolic processes are tightly regulated by neuronal and hormonal systems. The sympathetic system stimulates, whereas the parasympathetic system suppresses, hepatic gluconeogenesis. Insulin stimulates glycolysis and lipogenesis, but suppresses gluconeogenesis; glucagon counteracts insulin action. Numerous transcription factors and coactivators, including CREB, FOXO1, ChREBP, SREBP, PGC-1α, and CRTC2, control the expression of the enzymes which catalyze the rate-limiting steps of liver metabolic processes, thus controlling liver energy metabolism. Aberrant energy metabolism in the liver promotes insulin resistance, diabetes, and nonalcoholic fatty liver diseases (NAFLD). PMID:24692138

  5. Disruption of BCAA metabolism in mice impairs exercise metabolism and endurance.

    Science.gov (United States)

    She, Pengxiang; Zhou, Yingsheng; Zhang, Zhiyou; Griffin, Kathleen; Gowda, Kavitha; Lynch, Christopher J

    2010-04-01

    Exercise enhances branched-chain amino acid (BCAA) catabolism, and BCAA supplementation influences exercise metabolism. However, it remains controversial whether BCAA supplementation improves exercise endurance, and unknown whether the exercise endurance effect of BCAA supplementation requires catabolism of these amino acids. Therefore, we examined exercise capacity and intermediary metabolism in skeletal muscle of knockout (KO) mice of mitochondrial branched-chain aminotransferase (BCATm), which catalyzes the first step of BCAA catabolism. We found that BCATm KO mice were exercise intolerant with markedly decreased endurance to exhaustion. Their plasma lactate and lactate-to-pyruvate ratio in skeletal muscle during exercise and lactate release from hindlimb perfused with high concentrations of insulin and glucose were significantly higher in KO than wild-type (WT) mice. Plasma and muscle ammonia concentrations were also markedly higher in KO than WT mice during a brief bout of exercise. BCATm KO mice exhibited 43-79% declines in the muscle concentration of alanine, glutamine, aspartate, and glutamate at rest and during exercise. In response to exercise, the increments in muscle malate and alpha-ketoglutarate were greater in KO than WT mice. While muscle ATP concentration tended to be lower, muscle IMP concentration was sevenfold higher in KO compared with WT mice after a brief bout of exercise, suggesting elevated ammonia in KO is derived from the purine nucleotide cycle. These data suggest that disruption of BCAA transamination causes impaired malate/aspartate shuttle, thereby resulting in decreased alanine and glutamine formation, as well as increases in lactate-to-pyruvate ratio and ammonia in skeletal muscle. Thus BCAA metabolism may regulate exercise capacity in mice.

  6. Deiodinase knockdown during early zebrafish development affects growth, development, energy metabolism, motility and phototransduction.

    Directory of Open Access Journals (Sweden)

    Enise Bagci

    Full Text Available Thyroid hormone (TH balance is essential for vertebrate development. Deiodinase type 1 (D1 and type 2 (D2 increase and deiodinase type 3 (D3 decreases local intracellular levels of T3, the most important active TH. The role of deiodinase-mediated TH effects in early vertebrate development is only partially understood. Therefore, we investigated the role of deiodinases during early development of zebrafish until 96 hours post fertilization at the level of the transcriptome (microarray, biochemistry, morphology and physiology using morpholino (MO knockdown. Knockdown of D1+D2 (D1D2MO and knockdown of D3 (D3MO both resulted in transcriptional regulation of energy metabolism and (muscle development in abdomen and tail, together with reduced growth, impaired swim bladder inflation, reduced protein content and reduced motility. The reduced growth and impaired swim bladder inflation in D1D2MO could be due to lower levels of T3 which is known to drive growth and development. The pronounced upregulation of a large number of transcripts coding for key proteins in ATP-producing pathways in D1D2MO could reflect a compensatory response to a decreased metabolic rate, also typically linked to hypothyroidism. Compared to D1D2MO, the effects were more pronounced or more frequent in D3MO, in which hyperthyroidism is expected. More specifically, increased heart rate, delayed hatching and increased carbohydrate content were observed only in D3MO. An increase of the metabolic rate, a decrease of the metabolic efficiency and a stimulation of gluconeogenesis using amino acids as substrates may have been involved in the observed reduced protein content, growth and motility in D3MO larvae. Furthermore, expression of transcripts involved in purine metabolism coupled to vision was decreased in both knockdown conditions, suggesting that both may impair vision. This study provides new insights, not only into the role of deiodinases, but also into the importance of a correct

  7. Influence of anaesthesia on energy metabolism in surgery

    Directory of Open Access Journals (Sweden)

    Prigorodov М.V.

    2013-03-01

    Full Text Available The purpose of the article is to establish adequacy of protection of energy metabolism in a patient under anaes-thesiology in cholecystectomy from mini-access. Material et methods: 122 patients subjected to cholecystectomy from mini access have been surveyed. Among them 92 patients have got intravenous general anaesthesia with AVL, 30 patients have got prolonged epidural anaesthesia on spontaneous breath with insufflations of oxygen through an obverse mask with sedatations. Monitoring of energy-plastic metabolism has been carried out in all patients. Results: Groups of patients have been compared by anthropometrical data, traumatic interventions. In both groups of patients loss of energy to traumatic to an operation stage has insignificantly increased, but after the anaesthesia termination in the group of patients with intravenous anaesthesia loss of energy continued to rise, and in the group of patients with prolonged epidural blockade it has returned to the initial level. After the anaesthesia termination the energy metabolism became essential higher in the first group of patients in comparison with the second one (p <0,01. The energy-plastic metabolism increased in the first group of patients and decreased in the second. PEA during cholecystectomy from mini access provided a stable condition of energy and energy-plastic metabolism. The conclusion: The inspection of 122 patients subjected to cholecystectomy from mini access has established the following data: PEA on spontaneous breath with insufflations of oxygen through an obverse mask in comparison with intravenous general anaesthesia and AVL allows keeping on an optimum level of energy and energy-plastic metabolism.

  8. Cytolytic T lymphocyte responses to metabolically inactivated stimulator cells. I. Metabolic inactivation impairs both CD and LD antigen signals

    International Nuclear Information System (INIS)

    Kelso, A.; Boyle, W.

    1982-01-01

    The effects of metabolic inactivation of spleen cells on antigen presentation to precursors of alloreactive cytolytic T lymphocytes (T/sub c/) were examined. By serological methods, populations inactivated by ultraviolet irradiation, glutaraldehyde fixation or plasma membrane isolation were found to retain normal levels of H-2K/D and Ia antigens. However, comparison of the antigen doses required to stimulate secondary T/sub c/ responses in mixed leukocyte culture showed that the inactivated preparations were approximately 10-fold less immunogenic than X-irradiated spleen cells. Their total inability to stimulate primary cytolytic responses pointed to at least a 100-fold impairment of immunogenicity for unprimed T/sub c/ precursors in the case of uv-irradiated and glutaraldehyde-treated stimulator cells, and at least a 10-fold impairment for membrane fragments. Experiments showing that the capacity of cell monolayers to absorb precursor T/sub c/ from unprimed spleen populations was reduced following uv-irradiation or glutaraldehyde treatment provided direct evidence that this loss of immunogenicity was due in part to suboptimal antigen presentation to precursor T/sub c/. It is concluded that, in addition to the traditional view that these treatments damage the ''LD'' signal to helper T lymphocytes, metabolic inactivation also impairs recognition of ''CD'' determinants by precursor T/sub c/

  9. Glucose transportation in the brain and its impairment in Huntington disease: one more shade of the energetic metabolism failure?

    Science.gov (United States)

    Morea, Veronica; Bidollari, Eris; Colotti, Gianni; Fiorillo, Annarita; Rosati, Jessica; De Filippis, Lidia; Squitieri, Ferdinando; Ilari, Andrea

    2017-07-01

    Huntington's disease (HD) or Huntington's chorea is the most common inherited, dominantly transmitted, neurodegenerative disorder. It is caused by increased CAG repeats number in the gene coding for huntingtin (Htt) and characterized by motor, behaviour and psychiatric symptoms, ultimately leading to death. HD patients also exhibit alterations in glucose and energetic metabolism, which result in pronounced weight loss despite sustained calorie intake. Glucose metabolism decreases in the striatum of all the subjects with mutated Htt, but affects symptom presentation only when it drops below a specific threshold. Recent evidence points at defects in glucose uptake by the brain, and especially by neurons, as a relevant component of central glucose hypometabolism in HD patients. Here we review the main features of glucose metabolism and transport in the brain in physiological conditions and how these processes are impaired in HD, and discuss the potential ability of strategies aimed at increasing intracellular energy levels to counteract neurological and motor degeneration in HD patients.

  10. Serum Compounds of Energy Metabolism Impairment Are Related to Disability, Disease Course and Neuroimaging in Multiple Sclerosis.

    Science.gov (United States)

    Lazzarino, Giacomo; Amorini, Angela M; Petzold, Axel; Gasperini, Claudio; Ruggieri, Serena; Quartuccio, Maria Esmeralda; Lazzarino, Giuseppe; Di Stasio, Enrico; Tavazzi, Barbara

    2017-11-01

    Multiple sclerosis (MS) is characterized by primary inflammation, demyelination, and progressive neurodegeneration. A biochemical MS feature is neuronal mitochondrial dysfunction, compensated by anaerobic metabolism increase, likely aggravating progression of neurodegeneration. Here, we characterized a pragmatic serum profile of compounds related to mitochondrial energy metabolism of potential clinical use. Blood samples of 518 well characterized (disability, disease course) MS patients and 167 healthy controls were analyzed for serum purines, pyrimidines, creatinine, and lactate. Nine of the 15 compounds assayed, hypoxanthine, xanthine, uric acid, inosine, uracil, β-pseudouridine, uridine, creatinine, and lactate, differed significantly between MS patients and controls (p < 0.0001). Using these nine compounds, a unifying Biomarker Score was calculated. Controls and MS patients had mean Biomarker Scores of 0.4 ± 0.7 and 4.4 ± 1.9, respectively (p < 0.00001). The Biomarker Score was higher in patients with progressive (6.0 ± 1.8 than with relapsing remitting disease course (3.6 ± 1.5, p < 0.00001). High association between the Biomarker Score and increase in disability (EDSS) was also observed. Additionally, in 50 patients who underwent magnetic resonance imaging (MRI), increase in the Biomarker Score correlated to neuroanatomical alterations. These results, obtained in a large cohort of MS patients evaluated for serum metabolic compounds connected to energy metabolism, demonstrated that the Biomarker Score might represent a pragmatic, resource saving, easy to obtain, laboratory tool useful to monitor MS patients and predict at an early stage who will switch from an RR to a progressive disease course. For the first time, it was also clearly shown a link between mitochondrial dysfunction and MRI lesions characteristic of MS.

  11. 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.

  12. 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.

  13. Alteration patterns of brain glucose metabolism: comparisons of healthy controls, subjective memory impairment and mild cognitive impairment.

    Science.gov (United States)

    Song, In-Uk; Choi, Eun Kyoung; Oh, Jin Kyoung; Chung, Yong-An; Chung, Sung-Woo

    2016-01-01

    Some groups have focused on the detection and management of subjective memory impairment (SMI) as the stage that precedes mild cognitive impairment (MCI). However, there have been few clinical studies that have examined biomarkers of SMI to date. To investigate the differences in glucose metabolism as a prodromal marker of dementia in patients with SMI, MCI, and healthy controls using brain F-18 fluoro-2-deoxyglucose positron emission tomography (FDG-PET). Sixty-eight consecutive patients with SMI, 47 patients with MCI, and 42 age-matched healthy subjects were recruited. All subjects underwent FDG-PET and detailed neuropsychological testing. FDG-PET images were analyzed using the statistical parametric mapping (SPM) program. FDG-PET analysis showed glucose hypometabolism in the periventricular regions of patients with SMI and in the parietal, precentral frontal, and periventricular regions of patients with MCI compared with healthy controls. Interestingly, hypometabolism on FDG-PET was noted in the parietal and precentral frontal regions in MCI patients compared to SMI patients. The results suggest that hypometabolism in the periventricular regions as seen on FDG-PET may play a role as a predictive biomarker of pre-dementia, and the extension of reduced glucose metabolism into parietal regions likely reflects progression of cognitive deterioration. © The Foundation Acta Radiologica 2014.

  14. Sodium signaling and astrocyte energy metabolism

    KAUST Repository

    Chatton, Jean-Yves; Magistretti, Pierre J.; Barros, L. Felipe

    2016-01-01

    The Na+ gradient across the plasma membrane is constantly exploited by astrocytes as a secondary energy source to regulate the intracellular and extracellular milieu, and discard waste products. One of the most prominent roles of astrocytes in the brain is the Na+-dependent clearance of glutamate released by neurons during synaptic transmission. The intracellular Na+ load collectively generated by these processes converges at the Na,K-ATPase pump, responsible for Na+ extrusion from the cell, which is achieved at the expense of cellular ATP. These processes represent pivotal mechanisms enabling astrocytes to increase the local availability of metabolic substrates in response to neuronal activity. This review presents basic principles linking the intracellular handling of Na+ following activity-related transmembrane fluxes in astrocytes and the energy metabolic pathways involved. We propose a role of Na+ as an energy currency and as a mediator of metabolic signals in the context of neuron-glia interactions. We further discuss the possible impact of the astrocytic syncytium for the distribution and coordination of the metabolic response, and the compartmentation of these processes in cellular microdomains and subcellular organelles. Finally, we illustrate future avenues of investigation into signaling mechanisms aimed at bridging the gap between Na+ and the metabolic machinery. © 2016 Wiley Periodicals, Inc.

  15. Sodium signaling and astrocyte energy metabolism

    KAUST Repository

    Chatton, Jean-Yves

    2016-03-31

    The Na+ gradient across the plasma membrane is constantly exploited by astrocytes as a secondary energy source to regulate the intracellular and extracellular milieu, and discard waste products. One of the most prominent roles of astrocytes in the brain is the Na+-dependent clearance of glutamate released by neurons during synaptic transmission. The intracellular Na+ load collectively generated by these processes converges at the Na,K-ATPase pump, responsible for Na+ extrusion from the cell, which is achieved at the expense of cellular ATP. These processes represent pivotal mechanisms enabling astrocytes to increase the local availability of metabolic substrates in response to neuronal activity. This review presents basic principles linking the intracellular handling of Na+ following activity-related transmembrane fluxes in astrocytes and the energy metabolic pathways involved. We propose a role of Na+ as an energy currency and as a mediator of metabolic signals in the context of neuron-glia interactions. We further discuss the possible impact of the astrocytic syncytium for the distribution and coordination of the metabolic response, and the compartmentation of these processes in cellular microdomains and subcellular organelles. Finally, we illustrate future avenues of investigation into signaling mechanisms aimed at bridging the gap between Na+ and the metabolic machinery. © 2016 Wiley Periodicals, Inc.

  16. [sup 31]P-magnetic resonance spectroscopy: Impaired energy metabolism in latent hyperthyroidism. [sup 31]Phosphor-Kernspinspektroskopie: Gestoerter Energiestoffwechsel bei latenter Hyperthyreose

    Energy Technology Data Exchange (ETDEWEB)

    Theissen, P. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Kaldewey, S. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Moka, D. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Bunke, J. (Philips Medizin Systeme, Hamburg (Germany)); Voth, E. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Schicha, H. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany))

    1993-06-01

    [sup 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[sub 2]HPO[sub 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.)

  17. Changes in cerebral glucose metabolism in patients with posttraumatic cognitive impairment after memantine therapy. A preliminary study

    International Nuclear Information System (INIS)

    Kim, Yong-Wook; Shin, Ji-Cheol; An, Young-Sil

    2010-01-01

    The objective of this study was to investigate the changes in cerebral glucose metabolism in patients with posttraumatic cognitive impairment after memantine therapy. We performed serial F-18 fluorodeoxyglucose positron emission tomography studies before and after memantine therapy (20 mg per day) on 17 patients with posttraumatic cognitive impairment using statistical parametric mapping analysis. In addition, covariance analysis was performed to identify regions, where changes in regional cerebral glucose metabolism correlated significantly with increased Mini-Mental Status Examination scores. Statistical parametric mapping analysis demonstrated that, compared with baseline, significantly increased cerebral glucose metabolism occurred in both inferior, middle and superior frontal gyri, both angular gyri, both precuneus, the right middle cingulum, the left inferior parietal lobule, the left fusiform gyrus, the left precentral gyrus, the left paracentral lobule, and the left lingual gyrus after memantine therapy (P uncorrected uncorrected corrected <0.0001). Our findings indicate that the prefrontal and the parietal association cortices may be the relevant structures for the pharmacological response to memantine therapy in patients with posttraumatic cognitive impairment. (author)

  18. Increased lipolysis and energy expenditure in a mouse model with severely impaired glucagon secretion.

    Directory of Open Access Journals (Sweden)

    Phing-How Lou

    Full Text Available BACKGROUND: Secretion of insulin and glucagon is triggered by elevated intracellular calcium levels. Although the precise mechanism by which the calcium signal is coupled to insulin and glucagon granule exocytosis is unclear, synaptotagmin-7 has been shown to be a positive regulator of calcium-dependent insulin and glucagon secretion, and may function as a calcium sensor for insulin and glucagon granule exocytosis. Deletion of synaptotagmin-7 leads to impaired glucose-stimulated insulin secretion and nearly abolished Ca(2+-dependent glucagon secretion in mice. Under non-stressed resting state, however, synaptotagmin-7 KO mice exhibit normal insulin level but severely reduced glucagon level. METHODOLOGY/PRINCIPAL FINDINGS: We studied energy expenditure and metabolism in synaptotagmin-7 KO and control mice using indirect calorimetry and biochemical techniques. Synaptotagmin-7 KO mice had lower body weight and body fat content, and exhibited higher oxygen consumption and basal metabolic rate. Respiratory exchange ratio (RER was lower in synaptotagmin-7 KO mice, suggesting an increased use of lipid in their energy production. Consistent with lower RER, gene expression profiles suggest enhanced lipolysis and increased capacity for fatty acid transport and oxidation in synaptotagmin-7 KO mice. Furthermore, expression of uncoupling protein 3 (UCP3 in skeletal muscle was approximately doubled in the KO mice compared with control mice. CONCLUSIONS: These results show that the lean phenotype in synaptotagmin-7 KO mice was mostly attributed to increased lipolysis and energy expenditure, and suggest that reduced glucagon level may have broad influence on the overall metabolism in the mouse model.

  19. Sex differences in diet and inhaled ozone (O3) induced metabolic impairment

    Science.gov (United States)

    APS 2015 abstract Sex differences in diet and inhaled ozone (O3) induced metabolic impairment U.P. Kodavanti1, V.L. Bass2, M.C. Schladweiler1, C.J. Gordon3, K.A. Jarema1, P. Phillips1, A.D. Ledbetter1, D.B. Miller4, S. Snow5, J.E. Richards1. 1 EPHD, NHEERL, USEPA, Research Triang...

  20. Non-Q-wave myocardial infarction: impaired myocardial energy metabolism in regions with reduced 99mTc-MIBI accumulation.

    Science.gov (United States)

    Moka, D; Baer, F M; Theissen, P; Schneider, C A; Dietlein, M; Erdmann, E; Schicha, H

    2001-05-01

    Reduced regional technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) accumulation in patients with chronic non-Q-wave infarction (NQWI) but without significant coronary artery stenosis indicates non-transmural damage of the myocardial wall. The aim of this study was to characterise cardiac energy metabolism after NQWI using phosphorus-31 magnetic resonance spectroscopy (31P-MRS) and to compare the biochemical remodelling with changes in regional 99mTc-MIBI uptake and with morphological and functional parameters assessed by magnetic resonance imaging (MRI). Fifteen patients with a history of NQWI, exclusion of significant coronary artery stenosis (energy metabolism. Spectroscopic measurements were performed in the infarct-related myocardial region. Corresponding gradient-echo MR images and myocardial 99mTc-MIBI single-photon emission tomography images were acquired for exact localisation of the infarct region. All examinations were performed at rest under anti-ischaemic medication. Data were compared with those of patients in whom coronary artery disease had been excluded by angiography (group B, n=10). All patients of group A displayed anterior wall hypokinesia in the infarcted area on both ventriculography and MRI, with a reduced myocardial accumulation of 99mTc-MIBI (66.3%+/-11.8% vs 95.6%+/-2.2% in group B). The mean wall thickness during the complete cardiac cycle (9.5+/-1.8 mm vs 13.1+/-1.1 mm in group B, Penergy metabolism.

  1. Protein energy malnutrition impairs homeostatic proliferation of memory CD8 T cells.

    Science.gov (United States)

    Iyer, Smita S; Chatraw, Janel Hart; Tan, Wendy G; Wherry, E John; Becker, Todd C; Ahmed, Rafi; Kapasi, Zoher F

    2012-01-01

    Nutrition is a critical but poorly understood determinant of immunity. There is abundant epidemiological evidence linking protein malnutrition to impaired vaccine efficacy and increased susceptibility to infections; yet, the role of dietary protein in immune memory homeostasis remains poorly understood. In this study, we show that protein-energy malnutrition induced in mice by low-protein (LP) feeding has a detrimental impact on CD8 memory. Relative to adequate protein (AP)-fed controls, LP feeding in lymphocytic choriomeningitis virus (LCMV)-immune mice resulted in a 2-fold decrease in LCMV-specific CD8 memory T cells. Adoptive transfer of memory cells, labeled with a division tracking dye, from AP mice into naive LP or AP mice demonstrated that protein-energy malnutrition caused profound defects in homeostatic proliferation. Remarkably, this defect occurred despite the lymphopenic environment in LP hosts. Whereas Ag-specific memory cells in LP and AP hosts were phenotypically similar, memory cells in LP hosts were markedly less responsive to polyinosinic-polycytidylic acid-induced acute proliferative signals. Furthermore, upon recall, memory cells in LP hosts displayed reduced proliferation and protection from challenge with LCMV-clone 13, resulting in impaired viral clearance in the liver. The findings show a metabolic requirement of dietary protein in sustaining functional CD8 memory and suggest that interventions to optimize dietary protein intake may improve vaccine efficacy in malnourished individuals.

  2. The effect of impaired glucose metabolism on weight loss in multidisciplinary childhood obesity treatment

    DEFF Research Database (Denmark)

    Kloppenborg, Julie T; Gamborg, Michael; Fonvig, Cilius E

    2017-01-01

    and adolescents from the Children's Obesity Clinic, Holbaek, Denmark. Anthropometrics, pubertal development, socioeconomic status (SES), and fasting concentrations of plasma glucose, serum insulin, serum C-peptide, and whole blood glycosylated hemoglobin (HbA1c) were collected at treatment entry and at follow......OBJECTIVE: To investigate whether children and adolescents exhibiting an impaired glucose metabolism are more obese at treatment entry and less likely to reduce their degree of obesity during treatment. METHODS: The present study is a longitudinal observational study, including children...... mass index (BMI) z-score 2.94 (range 1.34-5.54) were included. The mean BMI z-score reduction was 0.31 (±0.46) after 13 months (range 6-18) of treatment. At treatment entry, patients with impaired estimates of glucose metabolism were more obese than normoglycemic patients. Baseline concentration of C...

  3. [Characteristics of cerebral glucose metabolism in patients with cognitive impairment in Parkinson's disease].

    Science.gov (United States)

    Homenko, Ju G; Susin, D S; Kataeva, G V; Irishina, Ju A; Zavolokov, I G

    To study the relationship between early cognitive impairment symptoms and cerebral glucose metabolism in different brain regions (according to the positron emission tomography (PET) data) in Parkinson's disease (PD) in order to increase the diagnostic and treatment efficacy. Two groups of patients with PD (stage I-III), including 11 patients without cognitive disorders and 13 with mild cognitive impairment (MCI), were examined. The control group included 10 age-matched people with normal cognition. To evaluate cognitive state, the Mini mental state examination (MMSE), the Frontal assessment battery (FAB) and the 'clock drawing test' were used. The regional cerebral glucose metabolism rate (CMRglu) was assessed using PET with 18F-fluorodeoxyglucose (FDG). In PD patients, CMRglu were decreased in the frontal (Brodmann areas (BA) 9, 10, 11, 46, 47), occipital (BA 19) and parietal (BA 39), temporal (BA 20, 37), and cingulate cortex (BA 32) compared to the control group. Cerebral glucose metabolism was decreased in the frontal (BA 8, 9, 10, 45, 46, 47), parietal (BA 7, 39, 40) and cingulate cortex (BA 23, 24, 31, 32) in the group of PD patients with MCI compared to PD patients with normal cognition. Hypometabolism in BA 7, 8, 23, 24, 31, 40 was revealed only in comparison of PD and PD-MCI groups, and did not appear in case of comparison of cognitively normal PD patients with the control group. It is possible to suggest that the mentioned above brain areas were associated with cognitive impairment. The revealed glucose hypometabolism pattern possibly has the diagnostic value for the early and preclinical diagnosis of MCI in PD and control of treatment efficacy.

  4. 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.

  5. Increased susceptibility to metabolic dysregulation in a mouse model of Alzheimer's disease is associated with impaired hypothalamic insulin signaling and elevated BCAA levels.

    Science.gov (United States)

    Ruiz, Henry H; Chi, Tiffany; Shin, Andrew C; Lindtner, Claudia; Hsieh, Wilson; Ehrlich, Michelle; Gandy, Sam; Buettner, Christoph

    2016-08-01

    Epidemiologic studies have demonstrated an association between diabetes and dementia. Insulin signaling within the brain, in particular within the hypothalamus regulates carbohydrate, lipid, and branched chain amino acid (BCAA) metabolism in peripheral organs such as the liver and adipose tissue. We hypothesized that cerebral amyloidosis impairs central nervous system control of metabolism through disruption of insulin signaling in the hypothalamus, which dysregulates glucose and BCAA homeostasis resulting in increased susceptibility to diabetes. We examined whether APP/PS1 mice exhibit increased susceptibility to aging or high-fat diet (HFD)-induced metabolic impairment using metabolic phenotyping and insulin-signaling studies. APP/PS1 mice were more susceptible to high-fat feeding and aging-induced metabolic dysregulation including disrupted BCAA homeostasis and exhibited impaired hypothalamic insulin signaling. Our data suggest that AD pathology increases susceptibility to diabetes due to impaired hypothalamic insulin signaling, and that plasma BCAA levels could serve as a biomarker of hypothalamic insulin action in patients with AD. Copyright © 2016 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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

  8. The obese Göttingen minipig as a model of the metabolic syndrome

    DEFF Research Database (Denmark)

    Johansen, T.; Malmlöf, K.; Hansen, Harald S.

    2001-01-01

    The objective of the study reported here was to induce obesity in the female Göttingen minipig to establish a model of the human metabolic syndrome. Nine- to ten-month-old female Göttingen minipigs received a high-fat high-energy (HFE) diet or a low-fat, low-energy (LFE) diet. The energy contents...... of the metabolic impairments seen in obese humans, and may thus serve as a model of the metabolic syndrome....

  9. Cellular energy metabolism in T-lymphocytes.

    Science.gov (United States)

    Gaber, Timo; Strehl, Cindy; Sawitzki, Birgit; Hoff, Paula; Buttgereit, Frank

    2015-01-01

    Energy homeostasis is a hallmark of cell survival and maintenance of cell function. Here we focus on the impact of cellular energy metabolism on T-lymphocyte differentiation, activation, and function in health and disease. We describe the role of transcriptional and posttranscriptional regulation of lymphocyte metabolism on immune functions of T cells. We also summarize the current knowledge about T-lymphocyte adaptations to inflammation and hypoxia, and the impact on T-cell behavior of pathophysiological hypoxia (as found in tumor tissue, chronically inflamed joints in rheumatoid arthritis and during bone regeneration). A better understanding of the underlying mechanisms that control immune cell metabolism and immune response may provide therapeutic opportunities to alter the immune response under conditions of either immunosuppression or inflammation, potentially targeting infections, vaccine response, tumor surveillance, autoimmunity, and inflammatory disorders.

  10. Microglia energy metabolism in metabolic disorder.

    Science.gov (United States)

    Kalsbeek, Martin J T; Mulder, Laurie; Yi, Chun-Xia

    2016-12-15

    Microglia are the resident macrophages of the CNS, and are in charge of maintaining a healthy microenvironment to ensure neuronal survival. Microglia carry out a non-stop patrol of the CNS, make contact with neurons and look for abnormalities, all of which requires a vast amount of energy. This non-signaling energy demand increases after activation by pathogens, neuronal damage or other kinds of stimulation. Of the three major energy substrates - glucose, fatty acids and glutamine - glucose is crucial for microglia survival and several glucose transporters are expressed to supply sufficient glucose influx. Fatty acids are another source of energy for microglia and have also been shown to strongly influence microglial immune activity. Glutamine, although possibly suitable for use as an energy substrate by microglia, has been shown to have neurotoxic effects when overloaded. Microglial fuel metabolism might be associated with microglial reactivity under different pathophysiological conditions and a microglial fuel switch may thus be the underlying cause of hypothalamic dysregulation, which is associated with obesity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Overexpression of SIRT1 in mouse forebrain impairs lipid/glucose metabolism and motor function.

    Directory of Open Access Journals (Sweden)

    Dongmei Wu

    Full Text Available SIRT1 plays crucial roles in glucose and lipid metabolism, and has various functions in different tissues including brain. The brain-specific SIRT1 knockout mice display defects in somatotropic signaling, memory and synaptic plasticity. And the female mice without SIRT1 in POMC neuron are more sensitive to diet-induced obesity. Here we created transgenic mice overexpressing SIRT1 in striatum and hippocampus under the control of CaMKIIα promoter. These mice, especially females, exhibited increased fat accumulation accompanied by significant upregulation of adipogenic genes in white adipose tissue. Glucose tolerance of the mice was also impaired with decreased Glut4 mRNA levels in muscle. Moreover, the SIRT1 overexpressing mice showed decreased energy expenditure, and concomitantly mitochondria-related genes were decreased in muscle. In addition, these mice showed unusual spontaneous physical activity pattern, decreased activity in open field and rotarod performance. Further studies demonstrated that SIRT1 deacetylated IRS-2, and upregulated phosphorylation level of IRS-2 and ERK1/2 in striatum. Meanwhile, the neurotransmitter signaling in striatum and the expression of endocrine hormones in hypothalamus and serum T3, T4 levels were altered. Taken together, our findings demonstrate that SIRT1 in forebrain regulates lipid/glucose metabolism and motor function.

  12. A Cellular Perspective on Brain Energy Metabolism and Functional Imaging

    KAUST Repository

    Magistretti, Pierre J.

    2015-05-01

    The energy demands of the brain are high: they account for at least 20% of the body\\'s energy consumption. Evolutionary studies indicate that the emergence of higher cognitive functions in humans is associated with an increased glucose utilization and expression of energy metabolism genes. Functional brain imaging techniques such as fMRI and PET, which are widely used in human neuroscience studies, detect signals that monitor energy delivery and use in register with neuronal activity. Recent technological advances in metabolic studies with cellular resolution have afforded decisive insights into the understanding of the cellular and molecular bases of the coupling between neuronal activity and energy metabolism and pointat a key role of neuron-astrocyte metabolic interactions. This article reviews some of the most salient features emerging from recent studies and aims at providing an integration of brain energy metabolism across resolution scales. © 2015 Elsevier Inc.

  13. Alcohol-Induced Impairment of Balance is Antagonized by Energy Drinks.

    Science.gov (United States)

    Marczinski, Cecile A; Fillmore, Mark T; Stamates, Amy L; Maloney, Sarah F

    2018-01-01

    The acute administration of alcohol reliably impairs balance and motor coordination. While it is common for consumers to ingest alcohol with other stimulant drugs (e.g., caffeine, nicotine), little is known whether prototypical alcohol-induced balance impairments are altered by stimulant drugs. The purpose of this study was to examine whether the coadministration of a high-caffeine energy drink with alcohol can antagonize expected alcohol-induced increases in body sway. Sixteen social drinkers (of equal gender) participated in 4 separate double-blind dose administration sessions that involved consumption of alcohol and energy drinks, alone and in combination. Following dose administration, participants completed automated assessments of balance stability (both eyes open and eyes closed) measured using the Biosway Portable Balance System. Participants completed several subjective measures including self-reported ratings of sedation, stimulation, fatigue, and impairment. Blood pressure and pulse rate were recorded repeatedly. The acute administration of alcohol increased body sway, and the coadministration of energy drinks antagonized this impairment. When participants closed their eyes, alcohol-induced body sway was similar whether or not energy drinks were ingested. While alcohol administration increased ratings of sedation and fatigue, energy drink administration increased ratings of stimulation and reduced ratings of fatigue. Modest increases in systolic and diastolic blood pressure following energy drink administration were also observed. Visual assessment of balance impairment is frequently used to indicate that an individual has consumed too much alcohol (e.g., as part of police-standardized field sobriety testing or by a bartender assessing when someone should no longer be served more alcohol). The current findings suggest that energy drinks can antagonize alcohol-induced increases in body sway, indicating that future work is needed to determine whether this

  14. Pareto optimality in organelle energy metabolism analysis.

    Science.gov (United States)

    Angione, Claudio; Carapezza, Giovanni; Costanza, Jole; Lió, Pietro; Nicosia, Giuseppe

    2013-01-01

    In low and high eukaryotes, energy is collected or transformed in compartments, the organelles. The rich variety of size, characteristics, and density of the organelles makes it difficult to build a general picture. In this paper, we make use of the Pareto-front analysis to investigate the optimization of energy metabolism in mitochondria and chloroplasts. Using the Pareto optimality principle, we compare models of organelle metabolism on the basis of single- and multiobjective optimization, approximation techniques (the Bayesian Automatic Relevance Determination), robustness, and pathway sensitivity analysis. Finally, we report the first analysis of the metabolic model for the hydrogenosome of Trichomonas vaginalis, which is found in several protozoan parasites. Our analysis has shown the importance of the Pareto optimality for such comparison and for insights into the evolution of the metabolism from cytoplasmic to organelle bound, involving a model order reduction. We report that Pareto fronts represent an asymptotic analysis useful to describe the metabolism of an organism aimed at maximizing concurrently two or more metabolite concentrations.

  15. A clinical study on cognitive impairment in post-ischemic stroke patients with metabolic syndrome

    Directory of Open Access Journals (Sweden)

    LI Chen

    2012-02-01

    Full Text Available Objective To explore the relation between metabolic syndrome (MetS and cognitive impairment after ischemic stroke. Methods Ninety-four cases of first ischemic stroke patients were divided into stroke without MetS group (n = 54 and stroke with MetS group (n = 40 according to the diagnostic criteria for MetS defined by Metabolic Syndrome Researching Group of Chinese Diabetes Society. All patients underwent Mini-Mental State Examination (MMSE, Clock Drawing Test (CDT, animal Verbal Fluency Test (aVFT, Trial Making Test-A (TMT-A at 2 weeks and 3 months after stroke to evaluate mental state such as verbal learning memory, and executive, attentional and visuospatial abilities. The incidence and development of cognitive impairment were also assessed. Results At 2 weeks and 3 months after stroke, the incidence of cognitive impairment were 24.47% (23/94 and 22.34% (21/94, respectively, and in the cognitive impairment patients the incidence of non-dementia were 21.28% (20/94 and 19.15% (18/94, while the incidence of dementia were 3.19% (3/94 and 3.19% (3/94, respectively. The incidence of cognitive impairment was higher in the stroke patients with MetS than the stroke patients without MetS, 37.50% (15/40 vs 14.81% (8/54 (Z = 2.500, P = 0.012 at 2 weeks after stroke and 35.00% (14/40 vs 12.96% (7/54 (Z = 2.513, P = 0.012 at 3 months after stroke. In the scores of MMSE, delay recall and CDT of the stroke patients with MetS were all lower than those without MetS at 2 weeks after stroke and at 3 months after stroke (P < 0.05, for all. The stroke patients with MetS had more cognition deterioration than the stroke patients without MetS at 3 months after stroke, the difference was significant (Z = 2.134, P = 0.033. Conclusion MetS can increase the incidence of cognitive impairment, especially non-dementia cognitive impairment in post ischemic stroke. Executive dysfunction and hypomnesis are often seen. The development of cognitive impairment in stroke patients

  16. Brain metabolic impairment of OSAS: evidence from MRS

    International Nuclear Information System (INIS)

    Shen Jie; Long Miaomiao; Shen Wen; Qi Ji

    2011-01-01

    Objective: To evaluate the impact of obstructive sleep apnea syndrome (OSAS) on human cerebral metabolism by using magnetic resonance spectroscopy (MRS). Materials and methods: Twenty-one severe OSAS patients, 14 mild-moderate OSAS patients, and 15 healthy control subjects were included. All subjects underwent MRS using the point-resolved echo spin spectroscopy (PRESS). Proton volumes of interest were placed in the bilateral frontal lobes and left temporal -parietal-occipital cortex, and left hippocampus. Results: 1. Compared to the controls, the NAA/Cr ratio was significantly decreased in the left frontal lobe in the severe OSAS group (P=0.004), and in the right frontal lobe in the severe (P=0.002) and mild-moderate (P=0.007) OSAS patients. The NAA/Cr ratio trended to be decreased in the left hippocampus in the OSAS patients compared to controls. 2. A significant increase in the ml/Cr ratio was detected in the right frontal regions in the severe (P=0.008) and mild-moderate (P<0.001) OSAS groups. 3. Clx/Cr ratio values were significantly smaller than controls in the left (P=0.006) and right (P=0.027) frontal regions. Conclusion: Bilateral frontal lobes are the vulnerable location in patients with OSAS. MRS can be used to screen the brain metabolic impairment. (authors)

  17. Capillary recruitment is impaired in essential hypertension and relates to insulin's metabolic and vascular actions

    NARCIS (Netherlands)

    Serne, EH; Gans, ROB; ter Maaten, JC; ter Wee, PM; Donker, AM; Stehouwer, CDA

    Objective: In patients with essential hypertension, defects in both the metabolic and vascular actions of insulin have been described. Impaired microvascular function, a well-established abnormality in essential hypertension, may explain part of these defects. In the present study we investigated

  18. Prevalence and characteristics of impaired glucose metabolism in patients referred to comprehensive cardiac rehabilitation: the DANSUK study

    DEFF Research Database (Denmark)

    Boas Soja, Anne Merete; Zwisler, Ann-Dorthe Olsen; Melchior, Thomas

    2006-01-01

    and mortality. We studied the prevalence of impaired glucose metabolism (T2DM, IGT and impaired fasting glucose; IFG) in patients referred to cardiac rehabilitation, and further studied whether we could identify groups in which an oral glucose tolerance test (OGTT) need not be performed. METHODS: As part...... of a cardiac rehabilitation trial, 201 patients participated. Patients without a diagnosis of T2DM (N=159) underwent an OGTT 3 months after inclusion. RESULTS: Forty-two patients (21%) had known T2DM at enrolment. Based on the OGTT, 26 patients (13%) had unrecognized T2DM, 36 (18%) had IGT and 19 (9%) were...... predictive value of 39%. CONCLUSION: More than 60% of the patients (123/201) referred to cardiac rehabilitation had impaired glucose metabolism and 18% of the screened patients (29/159) would be misclassified if an OGTT was omitted. IFG and IGT did not identify the same patients or the same cardiovascular...

  19. 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....

  20. Dissociation between brain amyloid deposition and metabolism in early mild cognitive impairment.

    Directory of Open Access Journals (Sweden)

    Liyong Wu

    Full Text Available The hypothetical model of dynamic biomarkers for Alzheimer's disease (AD describes high amyloid deposition and hypometabolism at the mild cognitive impairment (MCI stage. However, it remains unknown whether brain amyloidosis and hypometabolism follow the same trajectories in MCI individuals. We used the concept of early MCI (EMCI and late MCI (LMCI as defined by the Alzheimer's disease Neuroimaging Initiative (ADNI-Go in order to compare the biomarker profile between EMCI and LMCI.To examine the global and voxel-based neocortical amyloid burden and metabolism among individuals who are cognitively normal (CN, as well as those with EMCI, LMCI and mild AD.In the present study, 354 participants, including CN (n = 109, EMCI (n = 157, LMCI (n = 39 and AD (n = 49, were enrolled between September 2009 and November 2011 through ADNI-GO and ADNI-2. Brain amyloid load and metabolism were estimated using [(18F]AV45 and [(18F]fluorodeoxyglucose ([(18F]FDG PET, respectively. Uptake ratio images of [(18F]AV45 and [(18F]FDG were calculated by dividing the summed PET image by the median counts of the grey matter of the cerebellum and pons, respectively. Group differences of global [(18F]AV45 and [(18F]FDG were analyzed using ANOVA, while the voxel-based group differences were estimated using statistic parametric mapping (SPM.EMCI patients showed higher global [(18F]AV45 retention compared to CN and lower uptake compared to LMCI. SPM detected higher [(18F]AV45 uptake in EMCI compared to CN in the precuneus, posterior cingulate, medial and dorsal lateral prefrontal cortices, bilaterally. EMCI showed lower [(18F]AV45 retention than LMCI in the superior temporal, inferior parietal, as well as dorsal lateral prefrontal cortices, bilaterally. Regarding to the global [(18F]FDG, EMCI patients showed no significant difference from CN and a higher uptake ratio compared to LMCI. At the voxel level, EMCI showed higher metabolism in precuneus, hippocampus, entorhinal and

  1. 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 ...

  2. Physical Activity Dimensions Associated with Impaired Glucose Metabolism

    DEFF Research Database (Denmark)

    Amadid, Hanan; Johansen, Nanna B.; Bjerregaard, Anne-Louise

    2017-01-01

    Purpose Physical activity (PA) is important in the prevention of Type 2 diabetes, yet little is known about the role of specific dimensions of PA, including sedentary time in subgroups at risk for impaired glucose metabolism (IGM). We applied a data-driven decision tool to identify dimensions of PA...... identified subgroups in which different activity dimensions were associated with IGM. Methodology and results from this study may suggest a preliminary step toward the goal of tailoring and targeting PA interventions aimed at Type 2 diabetes prevention....... associated with IGM across age, sex, and body mass index (BMI) groups. Methods This cross-sectional study included 1501 individuals (mean (SD) age, 65.6 (6.8) yr) at high risk for Type 2 diabetes from the ADDITION-PRO study. PA was measured by an individually calibrated combined accelerometer and heart rate...

  3. Central acylated ghrelin improves memory function and hippocampal AMPK activation and partly reverses the impairment of energy and glucose metabolism in rats infused with β-amyloid.

    Science.gov (United States)

    Kang, Suna; Moon, Na Rang; Kim, Da Sol; Kim, Sung Hoon; Park, Sunmin

    2015-09-01

    Ghrelin is a gastric hormone released during the fasting state that targets the hypothalamus where it induces hunger; however, emerging evidence suggests it may also affect memory function. We examined the effect of central acylated-ghrelin and DES-acetylated ghrelin (native ghrelin) on memory function and glucose metabolism in an experimentally induced Alzheimer's disease (AD) rat model. AD rats were divided into 3 groups and Non-AD rats were used as a normal-control group. Each rat in the AD groups had intracerebroventricular (ICV) infusion of β-amyloid (25-35; 16.8nmol/day) into the lateral ventricle for 3 days, and then the pumps were changed to infuse either acylated-ghrelin (0.2nmol/h; AD-G), DES-acylated ghrelin (0.2nmol/h; AD-DES-G), or saline (control; AD-C) for 3 weeks. The Non-AD group had ICV infusion of β-amyloid (35-25) which does not deposit in the hippocampus. During the next 3 weeks memory function, food intake, body weight gain, body fat composition, and glucose metabolism were measured. AD-C exhibited greater β-amyloid deposition compared to Non-AD-C, and AD-G suppressed the increased β-amyloid deposition and potentiated the phosphorylation AMPK. In addition, AD-G increased the phosphorylation GSK and decreased the phosphorylation of Tau in comparison to AD-C and AD-DES-G. Cognitive function, measured by passive avoidance and water maze tests, was much lower in AD-C than Non-AD-C whereas AD-G but not AD-DES-G prevented the decrease (pglucose levels during an oral glucose tolerance test (OGTT) compared to the AD-C and AD-DES-G group (pmemory function, and energy and glucose metabolisms were partially improved, possibly due to less β-amyloid accumulation. This research suggests that interventions such as intermittent fasting to facilitate sustained elevations of acyl-ghrelin should be investigated for cognitive and metabolic benefits, especially in person with early symptoms of memory impairment. Copyright © 2015 Elsevier Inc. All rights

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Brain-derived neurotrophic factor, impaired glucose metabolism, and bipolar disorder course

    DEFF Research Database (Denmark)

    Mansur, Rodrigo B; Santos, Camila M; Rizzo, Lucas B

    2016-01-01

    OBJECTIVES: The neurotrophin brain-derived neurotrophic factor (BDNF) has been proposed as a potential biomarker in bipolar disorder (BD). However, current evidence is limited and results have been highly heterogeneous. This study aimed to assess the moderating effect of impaired glucose metabolism......, alcohol use, and IGM (P=.046). There was no effect of IGM (P=.860) and no interaction between BD diagnosis and IGM (P=.893). Peripheral BDNF levels were positively correlated with lifetime depressive episodes (Psuicide attempts (P=.021). IGM moderated...... the association between BDNF and the number of previous mood episodes (P

  6. 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.

  7. Identification of altered metabolic pathways in plasma and CSF in mild cognitive impairment and Alzheimer's disease using metabolomics.

    Directory of Open Access Journals (Sweden)

    Eugenia Trushina

    Full Text Available Alzheimer's Disease (AD currently affects more than 5 million Americans, with numbers expected to grow dramatically as the population ages. The pathophysiological changes in AD patients begin decades before the onset of dementia, highlighting the urgent need for the development of early diagnostic methods. Compelling data demonstrate that increased levels of amyloid-beta compromise multiple cellular pathways; thus, the investigation of changes in various cellular networks is essential to advance our understanding of early disease mechanisms and to identify novel therapeutic targets. We applied a liquid chromatography/mass spectrometry-based non-targeted metabolomics approach to determine global metabolic changes in plasma and cerebrospinal fluid (CSF from the same individuals with different AD severity. Metabolic profiling detected a total of significantly altered 342 plasma and 351 CSF metabolites, of which 22% were identified. Based on the changes of >150 metabolites, we found 23 altered canonical pathways in plasma and 20 in CSF in mild cognitive impairment (MCI vs. cognitively normal (CN individuals with a false discovery rate <0.05. The number of affected pathways increased with disease severity in both fluids. Lysine metabolism in plasma and the Krebs cycle in CSF were significantly affected in MCI vs. CN. Cholesterol and sphingolipids transport was altered in both CSF and plasma of AD vs. CN. Other 30 canonical pathways significantly disturbed in MCI and AD patients included energy metabolism, Krebs cycle, mitochondrial function, neurotransmitter and amino acid metabolism, and lipid biosynthesis. Pathways in plasma that discriminated between all groups included polyamine, lysine, tryptophan metabolism, and aminoacyl-tRNA biosynthesis; and in CSF involved cortisone and prostaglandin 2 biosynthesis and metabolism. Our data suggest metabolomics could advance our understanding of the early disease mechanisms shared in progression from CN to

  8. Impaired Glucose Metabolism Is Associated with Visit-to-Visit Blood Pressure Variability in Participants without Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Nobuo Sasaki

    2018-01-01

    Full Text Available We evaluated data from 10,088 participants without cardiovascular disease (CVD who underwent 75 g oral glucose tolerance tests and had more than four visits during the first 5 years following the test to investigate the association between impaired glucose metabolism and visit-to-visit blood pressure (BP variability. Participants were classified into groups of normal glucose tolerance (NGT, impaired fasting glucose (IFG, impaired glucose tolerance (IGT, and diabetes. Visit-to-visit BP variability was estimated for each individual using standard deviation (SD and coefficients of variation (CV, defined as SD/mean. SDs and CVs of systolic BP (SBP values were divided into quartiles. The samples falling in the highest quartile were considered as having high SD/CV. The adjusted odds ratio (OR for high SD of SBP in the IFG (OR, 1.39; P<0.003, IGT (OR, 1.26; P<0.001, and diabetes (OR, 1.54; P<0.001 groups was significantly higher than that for high SD of SBP in the NGT group. Similarly, the OR for high CV of SBP in the IGT and diabetes groups was significantly higher than that for high CV of SBP in the NGT group. In participants without CVD, impaired glucose metabolism may modulate visit-to-visit BP variability.

  9. Profile of Cardiovascular Risk Factors in Patients with Coronary Heart Disease, Normal and Impaired Carbohydrate Metabolism

    Directory of Open Access Journals (Sweden)

    І.V. Cherniavska

    2015-11-01

    Full Text Available The aim of research was to conduct the comparative analysis of the profile of cardiovascular risk factors in patients with coronary heart disease (CHD and normal either impaired carbohydrate metabolism. Materials and methods. One hundred and forty two patients were observed. In order to estimate the rate of different forms of CHD depending on the state of carbohydrate metabolism such groups were formed: the first group consisted of 83 patients with type 2 diabetes mellitus (DM, the second group involved 34 patients with impaired glucose tolerance (IGT, the third group consisted of 25 patients with normal carbohydrate metabolism. The ischemic changes of myocardium were detected by ambulatory ECG monitoring with the obligatory achievement of submaximal heart rate during the research. Results. Silent myocardial ischemia was educed in 19 (22.9 % patients with type 2 DM, in 3 (8.8 % persons with IGT and in 2 (8.0 % patients with normal carbohydrate metabolism. Smoking, burdened heredity, violation in the haemostatic system more often occurred in the group of patients with type 2 DM and silent myocardial ischemia in comparison with the patients with type 2 DM without CHD. The profile of general population cardiovascular risk factors in patients with CHD and type 2 DM belongs to the most unfavorable. At the same time for patients with early violations of carbohydrate metabolism and normal carbohydrate metabolism such profile statistically does not differentiate meaningfully. Conclusions. Patients with type 2 DM and silent myocardial ischemia as compared to patients with type 2 DM without CHD have more expressed violations of indexes of general population cardiovascular risk factors for certain.

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

    Directory of Open Access Journals (Sweden)

    Joe Alcock

    2015-09-01

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

  11. Metabolic drift in the aging brain.

    Science.gov (United States)

    Ivanisevic, Julijana; Stauch, Kelly L; Petrascheck, Michael; Benton, H Paul; Epstein, Adrian A; Fang, Mingliang; Gorantla, Santhi; Tran, Minerva; Hoang, Linh; Kurczy, Michael E; Boska, Michael D; Gendelman, Howard E; Fox, Howard S; Siuzdak, Gary

    2016-05-01

    Brain function is highly dependent upon controlled energy metabolism whose loss heralds cognitive impairments. This is particularly notable in the aged individuals and in age-related neurodegenerative diseases. However, how metabolic homeostasis is disrupted in the aging brain is still poorly understood. Here we performed global, metabolomic and proteomic analyses across different anatomical regions of mouse brain at different stages of its adult lifespan. Interestingly, while severe proteomic imbalance was absent, global-untargeted metabolomics revealed an energymetabolic drift or significant imbalance in core metabolite levels in aged mouse brains. Metabolic imbalance was characterized by compromised cellular energy status (NAD decline, increased AMP/ATP, purine/pyrimidine accumulation) and significantly altered oxidative phosphorylation and nucleotide biosynthesis and degradation. The central energy metabolic drift suggests a failure of the cellular machinery to restore metabostasis (metabolite homeostasis) in the aged brain and therefore an inability to respond properly to external stimuli, likely driving the alterations in signaling activity and thus in neuronal function and communication.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Impaired glucose metabolism and type 2 diabetes in apparently healthy senior citizens.

    Science.gov (United States)

    Medina Escobar, Pedro; Moser, Michel; Risch, Lorenz; Risch, Martin; Nydegger, Urs Ernst; Stanga, Zeno

    2015-01-01

    To estimate the prevalence of unknown impaired glucose metabolism, also referred to as prediabetes (PreD), and unknown type 2 diabetes mellitus (T2DM) among subjectively healthy Swiss senior citizens. The fasting plasma glucose (FPG) and glycated haemoglobin A(1c) (HbA(1c)) levels were used for screening. A total of 1 362 subjects were included (613 men and 749 women; age range 60-99 years). Subjects with known T2DM were excluded. The FPG was processed immediately for analysis under standardised preanalytical conditions in a cross-sectional cohort study; plasma glucose levels were measured by means of the hexokinase procedure, and HbA(1c) was measured chromatographically and classified using the current American Diabetes Association (ADA) criteria. The crude prevalence of individuals unaware of having prediabetic FPG or HbA(1c) levels, was 64.5% (n = 878). Analogously, unknown T2DM was found in 8.4% (n = 114) On the basis of HbA(1c) criteria alone, significantly more subjects with unknown fasting glucose impairment and laboratory T2DM could be identified than with the FPG. The prevalence of PreD as well as of T2DM increased with age. The mean HOMA indices (homeostasis model assessment) for the different age groups, between 2.12 and 2.59, are consistent with clinically hidden disease and are in agreement with the largely orderly Body Mass Indices found in the normal range. Laboratory evidence of impaired glucose metabolism and, to a lesser extent, unknown T2DM, has a high prevalence among subjectively healthy older Swiss individuals. Laboratory identification of people with unknown out-of-range glucose values and overt diabetic hyperglycaemia might improve the prognosis by delaying the emergence of overt disease.

  14. Recycling Energy to Restore Impaired Ankle Function during Human Walking

    NARCIS (Netherlands)

    Collins, S.H.; Kuo, A.D.

    2010-01-01

    Background: Humans normally dissipate significant energy during walking, largely at the transitions between steps. The ankle then acts to restore energy during push-off, which may be the reason that ankle impairment nearly always leads to poorer walking economy. The replacement of lost energy is

  15. Mice lacking prostaglandin E receptor subtype 4 manifest disrupted lipid metabolism attributable to impaired triglyceride clearance.

    Science.gov (United States)

    Cai, Yin; Ying, Fan; Song, Erfei; Wang, Yu; Xu, Aimin; Vanhoutte, Paul M; Tang, Eva Hoi-Ching

    2015-12-01

    Upon high-fat feeding, prostaglandin E receptor subtype 4 (EP4)-knockout mice gain less body weight than their EP4(+/+) littermates. We investigated the cause of the lean phenotype. The mice showed a 68.8% reduction in weight gain with diminished fat mass that was not attributable to reduced food intake, fat malabsorption, or increased energy expenditure. Plasma triglycerides in the mice were elevated by 244.9%. The increase in plasma triglycerides was independent of changes in hepatic very low density lipoprotein (VLDL)-triglyceride production or intestinal chylomicron-triglyceride synthesis. However, VLDL-triglyceride clearance was drastically impaired in the EP4-knockout mice. The absence of EP4 in mice compromised the activation of lipoprotein lipase (LPL), the key enzyme responsible for trafficking of plasma triglycerides into peripheral tissues. Deficiency in EP4 reduced hepatic mRNA expression of the transcriptional factor cAMP response element binding protein H (by 36.8%) and LPL activators, including apolipoprotein (Apo)a5 (by 40.2%) and Apoc2 (by 61.3%). In summary, the lean phenotype of EP4-deficient mice resulted from reduction in adipose tissue and accretion of other peripheral organs caused by impaired triglyceride clearance. The findings identify a new metabolic dimension in the physiologic role played by endogenous EP4. © FASEB.

  16. Metabolic regulation of neuronal plasticity by the energy sensor AMPK.

    Directory of Open Access Journals (Sweden)

    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.

  17. Glycogen metabolism in brain and neurons - astrocytes metabolic cooperation can be altered by pre- and neonatal lead (Pb) exposure.

    Science.gov (United States)

    Baranowska-Bosiacka, Irena; Falkowska, Anna; Gutowska, Izabela; Gąssowska, Magdalena; Kolasa-Wołosiuk, Agnieszka; Tarnowski, Maciej; Chibowska, Karina; Goschorska, Marta; Lubkowska, Anna; Chlubek, Dariusz

    2017-09-01

    Lead (Pb) is an environmental neurotoxin which particularly affects the developing brain but the molecular mechanism of its neurotoxicity still needs clarification. The aim of this paper was to examine whether pre- and neonatal exposure to Pb (concentration of Pb in rat offspring blood below the "threshold level") may affect the brain's energy metabolism in neurons and astrocytes via the amount of available glycogen. We investigated the glycogen concentration in the brain, as well as the expression of the key enzymes involved in glycogen metabolism in brain: glycogen synthase 1 (Gys1), glycogen phosphorylase (PYGM, an isoform active in astrocytes; and PYGB, an isoform active in neurons) and phosphorylase kinase β (PHKB). Moreover, the expression of connexin 43 (Cx43) was evaluated to analyze whether Pb poisoning during the early phase of life may affect the neuron-astrocytes' metabolic cooperation. This work shows for the first time that exposure to Pb in early life can impair brain energy metabolism by reducing the amount of glycogen and decreasing the rate of its metabolism. This reduction in brain glycogen level was accompanied by a decrease in Gys1 expression. We noted a reduction in the immunoreactivity and the gene expression of both PYGB and PYGM isoform, as well as an increase in the expression of PHKB in Pb-treated rats. Moreover, exposure to Pb induced decrease in connexin 43 immunoexpression in all the brain structures analyzed, both in astrocytes as well as in neurons. Our data suggests that exposure to Pb in the pre- and neonatal periods results in a decrease in the level of brain glycogen and a reduction in the rate of its metabolism, thereby reducing glucose availability, which as a further consequence may lead to the impairment of brain energy metabolism and the metabolic cooperation between neurons and astrocytes. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Prevalence of depression in individuals with impaired glucose metabolism or undiagnosed diabetes

    DEFF Research Database (Denmark)

    Nouwen, Arie; Nefs, Giesje; Caramlau, Isabela

    2011-01-01

    diagnosed type 2 diabetes (PDD) has not been the subject of a systematic review/meta-analysis. This study examined the prevalence of depression in IGM and UDD subjects relative to each other and to NGM and PDD subjects by reviewing the literature and conducting a meta-analysis of studies on this topic......OBJECTIVE: Meta-analyses have shown that the risk for depression is elevated in type 2 diabetes. Whether this risk in individuals with impaired glucose metabolism (IGM) or undiagnosed diabetes (UDD) is elevated relative to normal glucose metabolism (NGM) or decreased relative to previously....... RESEARCH DESIGN AND METHODS: EMBASE and MEDLINE databases were searched for articles published up to May 2010. All studies that compared the prevalence of depression in subjects with IGM and UDD were included. Odds ratios (ORs) were calculated using fixed and random-effects models. RESULTS: The meta-analysis...

  19. Neuronal glucose metabolism is impaired while astrocytic TCA cycling is unaffected at symptomatic stages in the hSOD1G93A mouse model of amyotrophic lateral sclerosis.

    Science.gov (United States)

    Tefera, Tesfaye W; Borges, Karin

    2018-01-01

    Although alterations in energy metabolism are known in ALS, the specific mechanisms leading to energy deficit are not understood. We measured metabolite levels derived from injected [1- 13 C]glucose and [1,2- 13 C]acetate (i.p.) in cerebral cortex and spinal cord extracts of wild type and hSOD1 G93A mice at onset and mid disease stages using high-pressure liquid chromatography, 1 H and 13 C nuclear magnetic resonance spectroscopy. Levels of spinal and cortical CNS total lactate, [3- 13 C]lactate, total alanine and [3- 13 C]alanine, but not cortical glucose and [1- 13 C]glucose, were reduced mostly at mid stage indicating impaired glycolysis. The [1- 13 C]glucose-derived [4- 13 C]glutamate, [4- 13 C]glutamine and [2- 13 C]GABA amounts were diminished at mid stage in cortex and both time points in spinal cord, suggesting decreased [3- 13 C]pyruvate entry into the TCA cycle. Lack of changes in [1,2- 13 C]acetate-derived [4,5- 13 C]glutamate, [4,5- 13 C]glutamine and [1,2- 13 C]GABA levels indicate unchanged astrocytic 13 C-acetate metabolism. Reduced levels of leucine, isoleucine and valine in CNS suggest compensatory breakdown to refill TCA cycle intermediate levels. Unlabelled, [2- 13 C] and [4- 13 C]GABA concentrations were decreased in spinal cord indicating that impaired glucose metabolism contributes to hyperexcitability and supporting the use of treatments which increase GABA amounts. In conclusion, CNS glucose metabolism is compromised, while astrocytic TCA cycling appears to be normal in the hSOD1 G93A mouse model at symptomatic disease stages.

  20. Ethanol metabolism by alcohol dehydrogenase or cytochrome P450 2E1 differentially impairs hepatic protein trafficking and growth hormone signaling.

    Science.gov (United States)

    Doody, Erin E; Groebner, Jennifer L; Walker, Jetta R; Frizol, Brittnee M; Tuma, Dean J; Fernandez, David J; Tuma, Pamela L

    2017-12-01

    The liver metabolizes alcohol using alcohol dehydrogenase (ADH) and cytochrome P 450 2E1 (CYP2E1). Both enzymes metabolize ethanol into acetaldehyde, but CYP2E1 activity also results in the production of reactive oxygen species (ROS) that promote oxidative stress. We have previously shown that microtubules are hyperacetylated in ethanol-treated polarized, hepatic WIF-B cells and livers from ethanol-fed rats. We have also shown that enhanced protein acetylation correlates with impaired clathrin-mediated endocytosis, constitutive secretion, and nuclear translocation and that the defects are likely mediated by acetaldehyde. However, the roles of CYP2E1-generated metabolites and ROS in microtubule acetylation and these alcohol-induced impairments have not been examined. To determine if CYP2E1-mediated alcohol metabolism is required for enhanced acetylation and the trafficking defects, we coincubated cells with ethanol and diallyl sulfide (DAS; a CYP2E1 inhibitor) or N -acetyl cysteine (NAC; an antioxidant). Both agents failed to prevent microtubule hyperacetylation in ethanol-treated cells and also failed to prevent impaired secretion or clathrin-mediated endocytosis. Somewhat surprisingly, both DAS and NAC prevented impaired STAT5B nuclear translocation. Further examination of microtubule-independent steps of the pathway revealed that Jak2/STAT5B activation by growth hormone was prevented by DAS and NAC. These results were confirmed in ethanol-exposed HepG2 cells expressing only ADH or CYP2E1. Using quantitative RT-PCR, we further determined that ethanol exposure led to blunted growth hormone-mediated gene expression. In conclusion, we determined that alcohol-induced microtubule acetylation and associated defects in microtubule-dependent trafficking are mediated by ADH metabolism whereas impaired microtubule-independent Jak2/STAT5B activation is mediated by CYP2E1 activity. NEW & NOTEWORTHY Impaired growth hormone-mediated signaling is observed in ethanol

  1. Regulation of Mitochondrial Function and Cellular Energy Metabolism by Protein Kinase C-λ/ι: A Novel Mode of Balancing Pluripotency

    Science.gov (United States)

    Mahato, Biraj; Home, Pratik; Rajendran, Ganeshkumar; Paul, Arindam; Saha, Biswarup; Ganguly, Avishek; Ray, Soma; Roy, Nairita; Swerdlow, Russell H.; Paul, Soumen

    2014-01-01

    Pluripotent stem cells (PSCs) contain functionally immature mitochondria and rely upon high rates of glycolysis for their energy requirements. Thus, altered mitochondrial function and promotion of aerobic glycolysis is key to maintain and induce pluripotency. However, signaling mechanisms that regulate mitochondrial function and reprogram metabolic preferences in self-renewing vs. differentiated PSC populations are poorly understood. Here, using murine embryonic stem cells (ESCs) as a model system, we demonstrate that atypical protein kinase C isoform, PKC lambda/iota (PKCλ/ι), is a key regulator of mitochondrial function in ESCs. Depletion of PKCλ/ι in ESCs maintains their pluripotent state as evident from germline offsprings. Interestingly, loss of PKCλ/ι in ESCs leads to impairment in mitochondrial maturation, organization and a metabolic shift toward glycolysis under differentiating condition. Our mechanistic analyses indicate that a PKCλ/ι-HIF1α-PGC1α axis regulates mitochondrial respiration and balances pluripotency in ESCs. We propose that PKCλ/ι could be a crucial regulator of mitochondrial function and energy metabolism in stem cells and other cellular contexts. PMID:25142417

  2. Obesity Impairs the Action of the Neuroendocrine Ghrelin System

    Science.gov (United States)

    Zigman, Jeffrey M.; Bouret, Sebastien G.; Andrews, Zane B.

    2016-01-01

    Ghrelin is a metabolic hormone that promotes energy conservation by regulating appetite and energy expenditure. Although some studies suggest that antagonizing ghrelin function attenuates body weight gain and glucose intolerance on a high calorie diet, there is little information about the metabolic actions of ghrelin in the obese state. In this review, we discuss the novel concept of obesity-induced central ghrelin resistance in neural circuits regulating behavior, and impaired ghrelin secretion from the stomach. Interestingly, weight loss restores ghrelin secretion and function, and we hypothesize that ghrelin resistance is a mechanism designed to protect a higher body weight set-point established during times of food availability, to maximize energy reserves during a time of food scarcity. PMID:26542050

  3. Testicular Metabolic Reprogramming in Neonatal Streptozotocin-Induced Type 2 Diabetic Rats Impairs Glycolytic Flux and Promotes Glycogen Synthesis

    Science.gov (United States)

    Rato, L.; Alves, M. G.; Dias, T. R.; Cavaco, J. E.; Oliveira, Pedro F.

    2015-01-01

    Defects in testicular metabolism are directly implicated with male infertility, but most of the mechanisms associated with type 2 diabetes- (T2DM) induced male infertility remain unknown. We aimed to evaluate the effects of T2DM on testicular glucose metabolism by using a neonatal-streptozotocin- (n-STZ) T2DM animal model. Plasma and testicular hormonal levels were evaluated using specific kits. mRNA and protein expression levels were assessed by real-time PCR and Western Blot, respectively. Testicular metabolic profile was assessed by 1H-NMR spectroscopy. T2DM rats showed increased glycemic levels, impaired glucose tolerance and hyperinsulinemia. Both testicular and serum testosterone levels were decreased, whereas those of 17β-estradiol were not altered. Testicular glycolytic flux was not favored in testicles of T2DM rats, since, despite the increased expression of both glucose transporters 1 and 3 and the enzyme phosphofructokinase 1, lactate dehydrogenase activity was severely decreased contributing to lower testicular lactate content. However, T2DM enhanced testicular glycogen accumulation, by modulating the availability of the precursors for its synthesis. T2DM also affected the reproductive sperm parameters. Taken together these results indicate that T2DM is able to reprogram testicular metabolism by enhancing alternative metabolic pathways, particularly glycogen synthesis, and such alterations are associated with impaired sperm parameters. PMID:26064993

  4. Metabolic fuel and clinical implications for female reproduction.

    Science.gov (United States)

    Mircea, Carmen N; Lujan, Marla E; Pierson, Roger A

    2007-11-01

    Reproduction is a physiologically costly process that consumes significant amounts of energy. The physiological mechanisms controlling energy balance are closely linked to fertility. This close relationship ensures that pregnancy and lactation occur only in favourable conditions with respect to energy. The primary metabolic cue that modulates reproduction is the availability of oxidizable fuel. An organism's metabolic status is transmitted to the brain through metabolic fuel detectors. There are many of these detectors at both the peripheral (e.g., leptin, insulin, ghrelin) and central (e.g., neuropeptide Y, melanocortin, orexins) levels. When oxidizable fuel is scarce, the detectors function to inhibit the release of gonadotropin-releasing hormone and luteinizing hormone, thereby altering steroidogenesis, reproductive cyclicity, and sexual behaviour. Infertility can also result when resources are abundant but food intake fails to compensate for increased energy demands. Examples of these conditions in women include anorexia nervosa and exercise-induced amenorrhea. Infertility associated with obesity appears to be less related to an effect of oxidizable fuel on the hypothalamic-pituitary-ovarian axis. Impaired insulin sensitivity may play a role in the etiology of these conditions, but their specific etiology remains unresolved. Research into the metabolic regulation of reproductive function has implications for elucidating mechanisms of impaired pubertal development, nutritional amenorrhea, and obesity-related infertility. A better understanding of these etiologies has far-reaching implications for the prevention and management of reproductive dysfunction and its associated comorbidities.

  5. 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...

  6. Role of free fatty acid receptors in the regulation of energy metabolism.

    Science.gov (United States)

    Hara, Takafumi; Kashihara, Daiji; Ichimura, Atsuhiko; Kimura, Ikuo; Tsujimoto, Gozoh; Hirasawa, Akira

    2014-09-01

    Free fatty acids (FFAs) are energy-generating nutrients that act as signaling molecules in various cellular processes. Several orphan G protein-coupled receptors (GPCRs) that act as FFA receptors (FFARs) have been identified and play important physiological roles in various diseases. FFA ligands are obtained from food sources and metabolites produced during digestion and lipase degradation of triglyceride stores. FFARs can be grouped according to ligand profiles, depending on the length of carbon chains of the FFAs. Medium- and long-chain FFAs activate FFA1/GPR40 and FFA4/GPR120. Short-chain FFAs activate FFA2/GPR43 and FFA3/GPR41. However, only medium-chain FFAs, and not long-chain FFAs, activate GPR84 receptor. A number of pharmacological and physiological studies have shown that these receptors are expressed in various tissues and are primarily involved in energy metabolism. Because an impairment of these processes is a part of the pathology of obesity and type 2 diabetes, FFARs are considered as key therapeutic targets. Here, we reviewed recently published studies on the physiological functions of these receptors, primarily focusing on energy homeostasis. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Metabolic Reprogramming During Multidrug Resistance in Leukemias

    Directory of Open Access Journals (Sweden)

    Raphael Silveira Vidal

    2018-04-01

    Full Text Available Cancer outcome has improved since introduction of target therapy. However, treatment success is still impaired by the same drug resistance mechanism of classical chemotherapy, known as multidrug resistance (MDR phenotype. This phenotype promotes resistance to drugs with different structures and mechanism of action. Recent reports have shown that resistance acquisition is coupled to metabolic reprogramming. High-gene expression, increase of active transport, and conservation of redox status are one of the few examples that increase energy and substrate demands. It is not clear if the role of this metabolic shift in the MDR phenotype is related to its maintenance or to its induction. Apart from the nature of this relation, the metabolism may represent a new target to avoid or to block the mechanism that has been impairing treatment success. In this mini-review, we discuss the relation between metabolism and MDR resistance focusing on the multiple non-metabolic functions that enzymes of the glycolytic pathway are known to display, with emphasis with the diverse activities of glyceraldehyde-3-phosphate dehydrogenase.

  8. Features of an altered AMPK metabolic pathway in Gilbert’s Syndrome, and its role in metabolic health

    OpenAIRE

    Christine Mölzer; Marlies Wallner; Carina Kern; Anela Tosevska; Ursula Schwarz; Rene Zadnikar; Daniel Doberer; Rodrig Marculescu; Karl-Heinz Wagner

    2016-01-01

    Energy metabolism, involving the ATP-dependent AMPK-PgC-Ppar pathway impacts metabolic health immensely, in that its impairment can lead to obesity, giving rise to disease. Based on observations that individuals with Gilbert?s syndrome (GS; UGT1A1 *28 promoter mutation) are generally lighter, leaner and healthier than controls, specific inter-group differences in the AMPK pathway regulation were explored. Therefore, a case-control study involving 120 fasted, healthy, age- and gender matched s...

  9. Association of Branched and Aromatic Amino Acids Levels with Metabolic Syndrome and Impaired Fasting Glucose in Hypertensive Patients

    OpenAIRE

    Weng, Liming; Quinlivan, Eoin; Gong, Yan; Beitelshees, Amber L.; Shahin, Mohamed H.; Turner, Stephen T.; Chapman, Arlene B.; Gums, John G.; Johnson, Julie A.; Frye, Reginald F.; Garrett, Timothy J.; Cooper-DeHoff, Rhonda M.

    2015-01-01

    Background: The three branched amino acids (valine, leucine, and isoleucine) and two aromatic amino acids (tyrosine and phenylalanine) have been associated with many adverse metabolic pathways, including diabetes. However, these associations have been identified primarily in otherwise healthy Caucasian populations. We aimed to investigate the association of this five-amino-acid signature with metabolic syndrome and impaired fasting glucose (IFG) in a hypertensive cohort of Caucasian and Afric...

  10. Combined MRI and ³¹P-MRS investigations of the ACTA1(H40Y mouse model of nemaline myopathy show impaired muscle function and altered energy metabolism.

    Directory of Open Access Journals (Sweden)

    Charlotte Gineste

    Full Text Available Nemaline myopathy (NM is the most common disease entity among non-dystrophic skeletal muscle congenital diseases. Mutations in the skeletal muscle α-actin gene (ACTA1 account for ∼25% of all NM cases and are the most frequent cause of severe forms of NM. So far, the mechanisms underlying muscle weakness in NM patients remain unclear. Additionally, recent Magnetic Resonance Imaging (MRI studies reported a progressive fatty infiltration of skeletal muscle with a specific muscle involvement in patients with ACTA1 mutations. We investigated strictly noninvasively the gastrocnemius muscle function of a mouse model carrying a mutation in the ACTA1 gene (H40Y. Skeletal muscle anatomy (hindlimb muscles and fat volumes and energy metabolism were studied using MRI and (31Phosphorus magnetic resonance spectroscopy. Skeletal muscle contractile performance was investigated while applying a force-frequency protocol (from 1-150 Hz and a fatigue protocol (80 stimuli at 40 Hz. H40Y mice showed a reduction of both absolute (-40% and specific (-25% maximal force production as compared to controls. Interestingly, muscle weakness was associated with an improved resistance to fatigue (+40% and an increased energy cost. On the contrary, the force frequency relationship was not modified in H40Y mice and the extent of fatty infiltration was minor and not different from the WT group. We concluded that the H40Y mouse model does not reproduce human MRI findings but shows a severe muscle weakness which might be related to an alteration of intrinsic muscular properties. The increased energy cost in H40Y mice might be related to either an impaired mitochondrial function or an alteration at the cross-bridges level. Overall, we provided a unique set of anatomic, metabolic and functional biomarkers that might be relevant for monitoring the progression of NM disease but also for assessing the efficacy of potential therapeutic interventions at a preclinical level.

  11. Early energy metabolism-related molecular events in skeletal muscle of diabetic rats: The effects of l-arginine and SOD mimic.

    Science.gov (United States)

    Stancic, Ana; Filipovic, Milos; Ivanovic-Burmazovic, Ivana; Masovic, Sava; Jankovic, Aleksandra; Otasevic, Vesna; Korac, Aleksandra; Buzadzic, Biljana; Korac, Bato

    2017-06-25

    Considering the vital role of skeletal muscle in control of whole-body metabolism and the severity of long-term diabetic complications, we aimed to reveal the molecular pattern of early diabetes-related skeletal muscle phenotype in terms of energy metabolism, focusing on regulatory mechanisms, and the possibility to improve it using two redox modulators, l-arginine and superoxide dismutase (SOD) mimic. Alloxan-induced diabetic rats (120 mg/kg) were treated with l-arginine or the highly specific SOD mimic, M40403, for 7 days. As appropriate controls, non-diabetic rats received the same treatments. We found that l-arginine and M40403 restored diabetes-induced impairment of phospho-5'-AMP-activated protein kinase α (AMPKα) signaling by upregulating AMPKα protein itself and its downstream effectors, peroxisome proliferator-activated receptor-γ coactivator-1α and nuclear respiratory factor 1. Also, there was a restitution of the protein levels of oxidative phosphorylation components (complex I, complex II and complex IV) and mitofusin 2. Furthermore, l-arginine and M40403 induced translocation of glucose transporter 4 to the membrane and upregulation of protein of phosphofructokinase and acyl coenzyme A dehydrogenase, diminishing negative diabetic effects on limiting factors of glucose and lipid metabolism. Both treatments abolished diabetes-induced downregulation of sarcoplasmic reticulum calcium-ATPase proteins (SERCA 1 and 2). Similar effects of l-arginine and SOD mimic treatments suggest that disturbances in the superoxide/nitric oxide ratio may be responsible for skeletal muscle mitochondrial and metabolic impairment in early diabetes. Our results provide evidence that l-arginine and SOD mimics have potential in preventing and treating metabolic disturbances accompanying this widespread metabolic disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Metabolic Dysfunction in Parkinson's Disease: Bioenergetics, Redox Homeostasis and Central Carbon Metabolism.

    Science.gov (United States)

    Anandhan, Annadurai; Jacome, Maria S; Lei, Shulei; Hernandez-Franco, Pablo; Pappa, Aglaia; Panayiotidis, Mihalis I; Powers, Robert; Franco, Rodrigo

    2017-07-01

    The loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and the accumulation of protein inclusions (Lewy bodies) are the pathological hallmarks of Parkinson's disease (PD). PD is triggered by genetic alterations, environmental/occupational exposures and aging. However, the exact molecular mechanisms linking these PD risk factors to neuronal dysfunction are still unclear. Alterations in redox homeostasis and bioenergetics (energy failure) are thought to be central components of neurodegeneration that contribute to the impairment of important homeostatic processes in dopaminergic cells such as protein quality control mechanisms, neurotransmitter release/metabolism, axonal transport of vesicles and cell survival. Importantly, both bioenergetics and redox homeostasis are coupled to neuro-glial central carbon metabolism. We and others have recently established a link between the alterations in central carbon metabolism induced by PD risk factors, redox homeostasis and bioenergetics and their contribution to the survival/death of dopaminergic cells. In this review, we focus on the link between metabolic dysfunction, energy failure and redox imbalance in PD, making an emphasis in the contribution of central carbon (glucose) metabolism. The evidence summarized here strongly supports the consideration of PD as a disorder of cell metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    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.

  14. 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.

  15. 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.

  16. 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...

  17. 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.

  18. 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

  19. 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

  20. Pathophysiology and molecular basis of selected metabolic abnormalities in Huntington's disease.

    Science.gov (United States)

    Krzysztoń-Russjan, Jolanta

    2016-12-30

    Huntington's disease (HD) is an incurable, devastating neurodegenerative disease with a known genetic background and autosomally dominant inheritance pattern. HTT gene mutation (mHTT) is associated with polymorphic fragment elongation above 35 repeats of the CAG triplet. The mHTT product is an altered protein with a poly-Q elongated fragment, with the highest expression determined in the central nervous system (CNS) and with differentiated expression outside the CNS. A drastic loss of striatal and deeper layers of the cerebral cortex neurons was determined in the CNS, but muscle and body weight mass loss with dysfunction of many organs was also observed. HD symptoms include neurological disturbances, such as choreal movements with dystonia, speech and swallowing impairments, and additionally a variety of psychiatric and behavioral symptoms with cognitive decline have been described. They are the result of disturbances of several cellular pathways related to signal transmission, mitochondrial dysfunction and energy metabolism impairment shown by gene and protein expression and alteration of their functions. Impairment of energy processes demonstrated by a decrease of ATP production and increase of oxidative stress markers was determined in- and outside of the CNS in glycolysis, the Krebs cycle and the electron transport chain. A correlation between the increase of energy metabolism impairment level and the increase in number of CAG repeats in HTT has often been described. The energy metabolism study is an initial stage of sensitive biomarkers and a new therapeutic investigative option for early application in order to inhibit pathological processes in HD. Identification of pathological changes outside the CNS requires a reevaluation of diagnostic and therapeutic rules in HD.

  1. 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

  2. 1Protein Energy Malnutrition Impairs Homeostatic Proliferation of Memory CD8 T cells

    Science.gov (United States)

    Iyer, Smita S.; Chatraw, Janel Hart; Tan, Wendy G.; Wherry, E. John; Becker, Todd C.; Ahmed, Rafi; Kapasi, Zoher F.

    2011-01-01

    Nutrition is a critical but poorly understood determinant of immunity. There is abundant epidemiological evidence linking protein malnutrition to impaired vaccine efficacy and increased susceptibility to infections; yet, the role of dietary protein in immune memory homeostasis remains poorly understood. Here we show that protein energy malnutrition (PEM) induced in mice by low-protein (LP) feeding has a detrimental impact on CD8 memory. Relative to adequate-protein (AP) fed controls, LP feeding in lymphocytic choriomeningitis virus (LCMV) immune mice resulted in a 2-fold decrease in LCMV-specific CD8 memory T cells. Adoptive transfer of memory cells, labeled with a division tracking dye, from AP mice into naive LP or AP mice demonstrated that PEM caused profound defects in homeostatic proliferation. Remarkably, this defect occurred despite the lymphopenic environment in LP hosts. While antigen-specific memory cells in LP and AP hosts were phenotypically similar, memory cells in LP hosts were markedly less-responsive to poly(I:C)-induced acute proliferative signals. Furthermore, upon recall, memory cells in LP hosts displayed reduced proliferation and protection from challenge with LCMV-clone 13 resulting in impaired viral clearance in the liver. The findings show a metabolic requirement of dietary protein in sustaining functional CD8 memory and suggest that interventions to optimize dietary protein intake may improve vaccine efficacy in malnourished individuals. PMID:22116826

  3. Towards an Understanding of Energy Impairment in Huntington’s Disease Brain

    Science.gov (United States)

    Dubinsky, Janet M.

    2017-01-01

    This review systematically examines the evidence for shifts in flux through energy generating biochemical pathways in Huntington’s disease (HD) brains from humans and model systems. Compromise of the electron transport chain (ETC) appears not to be the primary or earliest metabolic change in HD pathogenesis. Rather, compromise of glucose uptake facilitates glucose flux through glycolysis and may possibly decrease flux through the pentose phosphate pathway (PPP), limiting subsequent NADPH and GSH production needed for antioxidant protection. As a result, oxidative damage to key glycolytic and tricarboxylic acid (TCA) cycle enzymes further restricts energy production so that while basal needs may be met through oxidative phosphorylation, those of excessive stimulation cannot. Energy production may also be compromised by deficits in mitochondrial biogenesis, dynamics or trafficking. Restrictions on energy production may be compensated for by glutamate oxidation and/or stimulation of fatty acid oxidation. Transcriptional dysregulation generated by mutant huntingtin also contributes to energetic disruption at specific enzymatic steps. Many of the alterations in metabolic substrates and enzymes may derive from normal regulatory feedback mechanisms and appear oscillatory. Fine temporal sequencing of the shifts in metabolic flux and transcriptional and expression changes associated with mutant huntingtin expression remain largely unexplored and may be model dependent. Differences in disease progression among HD model systems at the time of experimentation and their varying states of metabolic compensation may explain conflicting reports in the literature. Progressive shifts in metabolic flux represent homeostatic compensatory mechanisms that maintain the model organism through presymptomatic and symptomatic stages. PMID:29125492

  4. 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.

  5. 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.

  6. Pathophysiology and molecular basis of selected metabolic abnormalities in Huntington’s disease

    Directory of Open Access Journals (Sweden)

    Jolanta Krzysztoń-Russjan

    2016-12-01

    Full Text Available Huntington’s disease (HD is an incurable, devastating neurodegenerative disease with a known genetic background and autosomally dominant inheritance pattern. HTT gene mutation (mHTT is associated with polymorphic fragment elongation above 35 repeats of the CAG triplet. The mHTT product is an altered protein with a poly-Q elongated fragment, with the highest expression determined in the central nervous system (CNS and with differentiated expression outside the CNS. A drastic loss of striatal and deeper layers of the cerebral cortex neurons was determined in the CNS, but muscle and body weight mass loss with dysfunction of many organs was also observed. HD symptoms include neurological disturbances, such as choreal movements with dystonia, speech and swallowing impairments, and additionally a variety of psychiatric and behavioral symptoms with cognitive decline have been described.They are the result of disturbances of several cellular pathways related to signal transmission, mitochondrial dysfunction and energy metabolism impairment shown by gene and protein expression and alteration of their functions. Impairment of energy processes demonstrated by a decrease of ATP production and increase of oxidative stress markers was determined in- and outside of the CNS in glycolysis, the Krebs cycle and the electron transport chain. A correlation between the increase of energy metabolism impairment level and the increase in number of CAG repeats in HTT has often been described. The energy metabolism study is an initial stage of sensitive biomarkers and a new therapeutic investigative option for early application in order to inhibit pathological processes in HD.Identification of pathological changes outside the CNS requires a reevaluation of diagnostic and therapeutic rules in HD.

  7. Peripheral inflammation acutely impairs human spatial memory via actions on medial temporal lobe glucose metabolism.

    Science.gov (United States)

    Harrison, Neil A; Doeller, Christian F; Voon, Valerie; Burgess, Neil; Critchley, Hugo D

    2014-10-01

    Inflammation impairs cognitive performance and is implicated in the progression of neurodegenerative disorders. Rodent studies demonstrated key roles for inflammatory mediators in many processes critical to memory, including long-term potentiation, synaptic plasticity, and neurogenesis. They also demonstrated functional impairment of medial temporal lobe (MTL) structures by systemic inflammation. However, human data to support this position are limited. Sequential fluorodeoxyglucose positron emission tomography together with experimentally induced inflammation was used to investigate effects of a systemic inflammatory challenge on human MTL function. Fluorodeoxyglucose positron emission tomography scanning was performed in 20 healthy participants before and after typhoid vaccination and saline control injection. After each scanning session, participants performed a virtual reality spatial memory task analogous to the Morris water maze and a mirror-tracing procedural memory control task. Fluorodeoxyglucose positron emission tomography data demonstrated an acute reduction in human MTL glucose metabolism after inflammation. The inflammatory challenge also selectively compromised human spatial, but not procedural, memory; this effect that was independent of actions on motivation or psychomotor response. Effects of inflammation on parahippocampal and rhinal glucose metabolism directly mediated actions of inflammation on spatial memory. These data demonstrate acute sensitivity of human MTL to mild peripheral inflammation, giving rise to associated functional impairment in the form of reduced spatial memory performance. Our findings suggest a mechanism for the observed epidemiologic link between inflammation and risk of age-related cognitive decline and progression of neurodegenerative disorders including Alzheimer's disease. Copyright © 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  8. Defects in muscle branched-chain amino acid oxidation contribute to impaired lipid metabolism.

    Science.gov (United States)

    Lerin, Carles; Goldfine, Allison B; Boes, Tanner; Liu, Manway; Kasif, Simon; Dreyfuss, Jonathan M; De Sousa-Coelho, Ana Luisa; Daher, Grace; Manoli, Irini; Sysol, Justin R; Isganaitis, Elvira; Jessen, Niels; Goodyear, Laurie J; Beebe, Kirk; Gall, Walt; Venditti, Charles P; Patti, Mary-Elizabeth

    2016-10-01

    Plasma levels of branched-chain amino acids (BCAA) are consistently elevated in obesity and type 2 diabetes (T2D) and can also prospectively predict T2D. However, the role of BCAA in the pathogenesis of insulin resistance and T2D remains unclear. To identify pathways related to insulin resistance, we performed comprehensive gene expression and metabolomics analyses in skeletal muscle from 41 humans with normal glucose tolerance and 11 with T2D across a range of insulin sensitivity (SI, 0.49 to 14.28). We studied both cultured cells and mice heterozygous for the BCAA enzyme methylmalonyl-CoA mutase (Mut) and assessed the effects of altered BCAA flux on lipid and glucose homeostasis. Our data demonstrate perturbed BCAA metabolism and fatty acid oxidation in muscle from insulin resistant humans. Experimental alterations in BCAA flux in cultured cells similarly modulate fatty acid oxidation. Mut heterozygosity in mice alters muscle lipid metabolism in vivo, resulting in increased muscle triglyceride accumulation, increased plasma glucose, hyperinsulinemia, and increased body weight after high-fat feeding. Our data indicate that impaired muscle BCAA catabolism may contribute to the development of insulin resistance by perturbing both amino acid and fatty acid metabolism and suggest that targeting BCAA metabolism may hold promise for prevention or treatment of T2D.

  9. Metabolic syndrome, impaired fasting glucose and obesity, as predictors of incident diabetes in 14 120 hypertensive patients of ASCOT-BPLA: comparison of their relative predictability using a novel approach.

    Science.gov (United States)

    Gupta, A K; Prieto-Merino, D; Dahlöf, B; Sever, P S; Poulter, N R

    2011-08-01

    To evaluate, in hypertensive patients, whether the metabolic syndrome is a better predictor of new-onset diabetes compared with impaired fasting glucose, obesity or its other individual components alone, or collectively. Cox models were developed to assess the risk of new-onset diabetes associated with the metabolic syndrome after adjusting for a priori confounders (age, sex, ethnicity and concomitant use of non-cardiovascular medications), its individual components and other determinants of new-onset diabetes. Area under receiver operator curves using the metabolic syndrome or models of impaired fasting glucose were compared, and the ability of these models to correctly identify those who (after 5-years of follow-up) would or would not develop diabetes was assessed. The metabolic syndrome adjusted for a priori confounders and its individual components, and further adjusted for other determinants, was associated with significantly increased risk of new-onset diabetes [1.19 (1.00-1.40), P = 0.05 and 1.22 (1.03-1.44), P = 0.02, respectively]. The discriminative ability of the metabolic syndrome model [area under receiver operating curve: 0.764 (0.750-0.778)] was significantly better than the model of impaired fasting glucose [0.742 (0.727-0.757)] (P fasting glucose status (37.7%) (P fasting glucose were associated with an approximately 9-fold (7.47-10.45) increased risk of new-onset diabetes. Among normoglycaemic patients, the metabolic syndrome was also associated with significantly increased risk of new-onset diabetes, after adjusting for BMI and a priori confounders [1.66 (1.29-2.13)]. Both impaired fasting glucose and the metabolic syndrome predict the risk of new-onset diabetes; however, the metabolic syndrome is a better predictor than impaired fasting glucose in assigning the risk of new-onset diabetes in hypertensive patients, and among those with normoglycaemia. © 2011 The Authors. Diabetic Medicine © 2011 Diabetes UK.

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

    Directory of Open Access Journals (Sweden)

    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

  11. Longitudinal brain metabolic changes from amnestic mild cognitive impairment to Alzheimer's disease

    Science.gov (United States)

    Fouquet, Marine; Desgranges, Béatrice; Landeau, Brigitte; Duchesnay, Edouard; Mézenge, Florence; De La Sayette, Vincent; Viader, Fausto; Baron, Jean-Claude; Eustache, Francis; Chételat, Gaël

    2009-01-01

    A sensitive marker for monitoring progression of early Alzheimer’s Disease (AD) would help to develop and test new therapeutic strategies. The present study aimed at investigating brain metabolism changes over time, as potential monitoring marker, in patients with amnestic Mild Cognitive Impairment (aMCI), according to their clinical outcome (converters or non-converters), and in relation to their cognitive decline. Seventeen aMCI patients underwent MRI and 18FDG-PET scans both at inclusion and 18 months later. Baseline and follow-up PET data were corrected for partial volume effects and spatially normalized using MRI data, scaled to the vermis and compared using SPM2. ‘PET-PAC’ maps reflecting metabolic percent annual changes were created for correlation analyses with cognitive decline. In the whole sample, the greatest metabolic decrease concerned the posterior cingulate-precuneus area. Converters had significantly greater metabolic decrease than nonconverters in two ventro-medial prefrontal areas, the subgenual (BA25) and anterior cingulate (BA24/32). PET-PAC in BA25 and BA24/32 combined allowed complete between-group discrimination. BA25 PET-PAC significantly correlated with both cognitive decline and PET-PAC in the hippocampal region and temporal pole, while BA24/32 PET-PAC correlated with posterior cingulate PET-PAC. Finally, the metabolic change in BA8/9/10 was inversely related to that in BA25 and showed relative increase with cognitive decline, suggesting that compensatory processes may occur in this dorso-medial prefrontal region. The observed ventro-medial prefrontal disruption is likely to reflect disconnection from the hippocampus, both indirectly through the cingulum bundle and posterior cingulate cortex for BA24/32, and directly through the uncinate fasciculus for BA25. Altogether, our findings emphasize the potential of 18FDG-PET for monitoring early AD progression. PMID:19477964

  12. The critical role of phosphatidylcholine and phosphatidylethanolamine metabolism in health and disease.

    Science.gov (United States)

    van der Veen, Jelske N; Kennelly, John P; Wan, Sereana; Vance, Jean E; Vance, Dennis E; Jacobs, René L

    2017-09-01

    Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) are the most abundant phospholipids in all mammalian cell membranes. In the 1950s, Eugene Kennedy and co-workers performed groundbreaking research that established the general outline of many of the pathways of phospholipid biosynthesis. In recent years, the importance of phospholipid metabolism in regulating lipid, lipoprotein and whole-body energy metabolism has been demonstrated in numerous dietary studies and knockout animal models. The purpose of this review is to highlight the unappreciated impact of phospholipid metabolism on health and disease. Abnormally high, and abnormally low, cellular PC/PE molar ratios in various tissues can influence energy metabolism and have been linked to disease progression. For example, inhibition of hepatic PC synthesis impairs very low density lipoprotein secretion and changes in hepatic phospholipid composition have been linked to fatty liver disease and impaired liver regeneration after surgery. The relative abundance of PC and PE regulates the size and dynamics of lipid droplets. In mitochondria, changes in the PC/PE molar ratio affect energy production. We highlight data showing that changes in the PC and/or PE content of various tissues are implicated in metabolic disorders such as atherosclerosis, insulin resistance and obesity. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Wireless Energy Harvesting Two-Way Relay Networks with Hardware Impairments.

    Science.gov (United States)

    Peng, Chunling; Li, Fangwei; Liu, Huaping

    2017-11-13

    This paper considers a wireless energy harvesting two-way relay (TWR) network where the relay has energy-harvesting abilities and the effects of practical hardware impairments are taken into consideration. In particular, power splitting (PS) receiver is adopted at relay to harvests the power it needs for relaying the information between the source nodes from the signals transmitted by the source nodes, and hardware impairments is assumed suffered by each node. We analyze the effect of hardware impairments [-20]on both decode-and-forward (DF) relaying and amplify-and-forward (AF) relaying networks. By utilizing the obtained new expressions of signal-to-noise-plus-distortion ratios, the exact analytical expressions of the achievable sum rate and ergodic capacities for both DF and AF relaying protocols are derived. Additionally, the optimal power splitting (OPS) ratio that maximizes the instantaneous achievable sum rate is formulated and solved for both protocols. The performances of DF and AF protocols are evaluated via numerical results, which also show the effects of various network parameters on the system performance and on the OPS ratio design.

  14. 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.

  15. Why is coronary collateral growth impaired in type II diabetes and the metabolic syndrome?

    Science.gov (United States)

    Rocic, Petra

    2012-01-01

    Type II diabetes and the metabolic syndrome are strong predictors of severity of occlusive coronary disease and poorer outcomes of coronary revascularization therapies. Coronary collateral growth can provide an alternative or accessory pathway of revascularization. However, collateral growth is impaired in type II diabetes and the metabolic syndrome. Although many factors necessary for collateral growth are known and many interventions have shown promising results in animal studies, not a single attempt to induce coronary collateral growth in human clinical trials has led to satisfactory results. Accordingly, the first part of this review outlines the known deleterious effects of diabetes and the metabolic syndrome on factors necessary for collateral growth, including pro-angiogenic growth factors, endothelial function, the redox state of the coronary circulation, intracellular signaling, leukocytes and bone marrow-derived progenitors cells. The second section highlights the gaps in our current knowledge of how these factors interact with the radically altered environment of the coronary circulation in diabetes and the metabolic syndrome. The interplay between these pathologies and inadequately explored areas related to the temporal regulation of collateral remodeling and the roles of the extracellular matrix, vascular cell phenotype and pro-inflammatory cytokines are emphasized with implications to development of efficient therapies. PMID:22342811

  16. Fermentation of Xylose Causes Inefficient Metabolic State Due to Carbon/Energy Starvation and Reduced Glycolytic Flux in Recombinant Industrial Saccharomyces cerevisiae

    Science.gov (United States)

    Matsushika, Akinori; Nagashima, Atsushi; Goshima, Tetsuya; Hoshino, Tamotsu

    2013-01-01

    In the present study, comprehensive, quantitative metabolome analysis was carried out on the recombinant glucose/xylose-cofermenting S. cerevisiae strain MA-R4 during fermentation with different carbon sources, including glucose, xylose, or glucose/xylose mixtures. Capillary electrophoresis time-of-flight mass spectrometry was used to determine the intracellular pools of metabolites from the central carbon pathways, energy metabolism pathways, and the levels of twenty amino acids. When xylose instead of glucose was metabolized by MA-R4, glycolytic metabolites including 3- phosphoglycerate, 2- phosphoglycerate, phosphoenolpyruvate, and pyruvate were dramatically reduced, while conversely, most pentose phosphate pathway metabolites such as sedoheptulose 7- phosphate and ribulose 5-phosphate were greatly increased. These results suggest that the low metabolic activity of glycolysis and the pool of pentose phosphate pathway intermediates are potential limiting factors in xylose utilization. It was further demonstrated that during xylose fermentation, about half of the twenty amino acids declined, and the adenylate/guanylate energy charge was impacted due to markedly decreased adenosine triphosphate/adenosine monophosphate and guanosine triphosphate/guanosine monophosphate ratios, implying that the fermentation of xylose leads to an inefficient metabolic state where the biosynthetic capabilities and energy balance are severely impaired. In addition, fermentation with xylose alone drastically increased the level of citrate in the tricarboxylic acid cycle and increased the aromatic amino acids tryptophan and tyrosine, strongly supporting the view that carbon starvation was induced. Interestingly, fermentation with xylose alone also increased the synthesis of the polyamine spermidine and its precursor S-adenosylmethionine. Thus, differences in carbon substrates, including glucose and xylose in the fermentation medium, strongly influenced the dynamic metabolism of MA-R4

  17. Maternal melatonin programs the daily pattern of energy metabolism in adult offspring.

    Directory of Open Access Journals (Sweden)

    Danilo S Ferreira

    Full Text Available BACKGROUND: Shift work was recently described as a factor that increases the risk of Type 2 diabetes mellitus. In addition, rats born to mothers subjected to a phase shift throughout pregnancy are glucose intolerant. However, the mechanism by which a phase shift transmits metabolic information to the offspring has not been determined. Among several endocrine secretions, phase shifts in the light/dark cycle were described as altering the circadian profile of melatonin production by the pineal gland. The present study addresses the importance of maternal melatonin for the metabolic programming of the offspring. METHODOLOGY/PRINCIPAL FINDINGS: Female Wistar rats were submitted to SHAM surgery or pinealectomy (PINX. The PINX rats were divided into two groups and received either melatonin (PM or vehicle. The SHAM, the PINX vehicle and the PM females were housed with male Wistar rats. Rats were allowed to mate and after weaning, the male and female offspring were subjected to a glucose tolerance test (GTT, a pyruvate tolerance test (PTT and an insulin tolerance test (ITT. Pancreatic islets were isolated for insulin secretion, and insulin signaling was assessed in the liver and in the skeletal muscle by western blots. We found that male and female rats born to PINX mothers display glucose intolerance at the end of the light phase of the light/dark cycle, but not at the beginning. We further demonstrate that impaired glucose-stimulated insulin secretion and hepatic insulin resistance are mechanisms that may contribute to glucose intolerance in the offspring of PINX mothers. The metabolic programming described here occurs due to an absence of maternal melatonin because the offspring born to PINX mothers treated with melatonin were not glucose intolerant. CONCLUSIONS/SIGNIFICANCE: The present results support the novel concept that maternal melatonin is responsible for the programming of the daily pattern of energy metabolism in their offspring.

  18. Interactions between negative energy balance, metabolic diseases, uterine health and immune response in transition dairy cows.

    Science.gov (United States)

    Esposito, Giulia; Irons, Pete C; Webb, Edward C; Chapwanya, Aspinas

    2014-01-30

    The biological cycles of milk production and reproduction determine dairying profitability thus making management decisions dynamic and time-dependent. Diseases also negatively impact on net earnings of a dairy enterprise. Transition cows in particular face the challenge of negative energy balance (NEB) and/or disproportional energy metabolism (fatty liver, ketosis, subacute, acute ruminal acidosis); disturbed mineral utilization (milk fever, sub-clinical hypocalcemia); and perturbed immune function (retained placenta, metritis, mastitis). Consequently NEB and reduced dry matter intake are aggravated. The combined effects of all these challenges are reduced fertility and milk production resulting in diminishing profits. Risk factors such as NEB, inflammation and impairment of the immune response are highly cause-and-effect related. Thus, managing cows during the transition period should be geared toward reducing NEB or feeding specially formulated diets to improve immunity. Given that all cows experience a reduced feed intake and body condition, infection and inflammation of the uterus after calving, there is a need for further research on the immunology of transition dairy cows. Integrative approaches at the molecular, cellular and animal level may unravel the complex interactions between disturbed metabolism and immune function that predispose cows to periparturient diseases. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. RAS signalling in energy metabolism and rare human diseases.

    Science.gov (United States)

    Dard, L; Bellance, N; Lacombe, D; Rossignol, R

    2018-05-08

    The RAS pathway is a highly conserved cascade of protein-protein interactions and phosphorylation that is at the heart of signalling networks that govern proliferation, differentiation and cell survival. Recent findings indicate that the RAS pathway plays a role in the regulation of energy metabolism via the control of mitochondrial form and function but little is known on the participation of this effect in RAS-related rare human genetic diseases. Germline mutations that hyperactivate the RAS pathway have been discovered and linked to human developmental disorders that are known as RASopathies. Individuals with RASopathies, which are estimated to affect approximately 1/1000 human birth, share many overlapping characteristics, including cardiac malformations, short stature, neurocognitive impairment, craniofacial dysmorphy, cutaneous, musculoskeletal, and ocular abnormalities, hypotonia and a predisposition to developing cancer. Since the identification of the first RASopathy, type 1 neurofibromatosis (NF1), which is caused by the inactivation of neurofibromin 1, several other syndromes have been associated with mutations in the core components of the RAS-MAPK pathway. These syndromes include Noonan syndrome (NS), Noonan syndrome with multiple lentigines (NSML), which was formerly called LEOPARD syndrome, Costello syndrome (CS), cardio-facio-cutaneous syndrome (CFC), Legius syndrome (LS) and capillary malformation-arteriovenous malformation syndrome (CM-AVM). Here, we review current knowledge about the bioenergetics of the RASopathies and discuss the molecular control of energy homeostasis and mitochondrial physiology by the RAS pathway. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. 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.

  1. Adipocyte Glucocorticoid Receptor Deficiency Attenuates Aging- and HFD-Induced Obesity and Impairs the Feeding-Fasting Transition.

    Science.gov (United States)

    Mueller, Kristina M; Hartmann, Kerstin; Kaltenecker, Doris; Vettorazzi, Sabine; Bauer, Mandy; Mauser, Lea; Amann, Sabine; Jall, Sigrid; Fischer, Katrin; Esterbauer, Harald; Müller, Timo D; Tschöp, Matthias H; Magnes, Christoph; Haybaeck, Johannes; Scherer, Thomas; Bordag, Natalie; Tuckermann, Jan P; Moriggl, Richard

    2017-02-01

    Glucocorticoids (GCs) are important regulators of systemic energy metabolism, and aberrant GC action is linked to metabolic dysfunctions. Yet, the extent to which normal and pathophysiological energy metabolism depend on the GC receptor (GR) in adipocytes remains unclear. Here, we demonstrate that adipocyte GR deficiency in mice significantly impacts systemic metabolism in different energetic states. Plasma metabolomics and biochemical analyses revealed a marked global effect of GR deficiency on systemic metabolite abundance and, thus, substrate partitioning in fed and fasted states. This correlated with a decreased lipolytic capacity of GR-deficient adipocytes under postabsorptive and fasting conditions, resulting from impaired signal transduction from β-adrenergic receptors to adenylate cyclase. Upon prolonged fasting, the impaired lipolytic response resulted in abnormal substrate utilization and lean mass wasting. Conversely, GR deficiency attenuated aging-/diet-associated obesity, adipocyte hypertrophy, and liver steatosis. Systemic glucose tolerance was improved in obese GR-deficient mice, which was associated with increased insulin signaling in muscle and adipose tissue. We conclude that the GR in adipocytes exerts central but diverging roles in the regulation of metabolic homeostasis depending on the energetic state. The adipocyte GR is indispensable for the feeding-fasting transition but also promotes adiposity and associated metabolic disorders in fat-fed and aged mice. © 2017 by the American Diabetes Association.

  2. Some considerations of the energy spectrum of odd-odd deformed nuclei; Quelqes considerations sur le spectre d'energie des noyaux impair-impair deformes

    Energy Technology Data Exchange (ETDEWEB)

    Alceanu-G, Pinho de; Picard, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    The odd-odd deformed nuclei are described as a rotator plus two odd nucleons moving in orbitals {omega}{sub p} and {omega}{sub n} of the deformed potential. We investigate the energies and wave functions of the various states of the ({omega}{sub p}, {omega}{sub n}) configurations by calculating and numerically diagonalizing the Hamiltonian matrix (with R.P.C. and residual interactions). The Gallagher-Mosskowski coupling rules ana the abnormal K equals 0 rotational bands are discussed. (authors) [French] Les noyaux impair-impairs deformes sont decrits comme un rotateur plus deux nucleons non apparies dans les orbites {omega}{sub p} et {omega}{sub n} du potentiel deforme. Nous etudions le spectre d'energie et les fonctions d'onde des configurations ({omega}{sub p}, {omega}{sub n}) en tenant compte de l'interaction particule-rotation et de la force residuelle entre les deux nucleons celibataires.

  3. Symptoms of depression in people with impaired glucose metabolism or Type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Adriaanse, M C; Dekker, J M; Heine, R. J.

    2008-01-01

    .28] and women with DM2 (OR = 3.18, 95% CI = 1.31 to 7.74). In men, depression was not associated with IGM (OR = 0.90, 95% CI = 0.32 to 2.57) and non-significantly more common in DM2 (OR = 2.04, 95% CI = 0.75 to 5.49). Adjustment for cardiovascular risk factors, cardiovascular disease and diabetes symptoms...... reduced the strength of these associations. CONCLUSIONS: Depressive symptoms are more common in women with IGM, but not men. Adjustment for cardiovascular risk factors, cardiovascular disease and diabetes symptoms partially attenuated these associations, suggesting that these variables could......OBJECTIVE: To study the prevalence and risk factors of depressive symptoms, comparing subjects with normal glucose metabolism (NGM), impaired glucose metabolism (IGM) or Type 2 diabetes mellitus (DM2). RESEARCH DESIGN AND METHODS: Cross-sectional data from a population-based cohort study conducted...

  4. 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

  5. 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.

  6. Defects in muscle branched-chain amino acid oxidation contribute to impaired lipid metabolism

    Directory of Open Access Journals (Sweden)

    Carles Lerin

    2016-10-01

    Full Text Available Objective: Plasma levels of branched-chain amino acids (BCAA are consistently elevated in obesity and type 2 diabetes (T2D and can also prospectively predict T2D. However, the role of BCAA in the pathogenesis of insulin resistance and T2D remains unclear. Methods: To identify pathways related to insulin resistance, we performed comprehensive gene expression and metabolomics analyses in skeletal muscle from 41 humans with normal glucose tolerance and 11 with T2D across a range of insulin sensitivity (SI, 0.49 to 14.28. We studied both cultured cells and mice heterozygous for the BCAA enzyme methylmalonyl-CoA mutase (Mut and assessed the effects of altered BCAA flux on lipid and glucose homeostasis. Results: Our data demonstrate perturbed BCAA metabolism and fatty acid oxidation in muscle from insulin resistant humans. Experimental alterations in BCAA flux in cultured cells similarly modulate fatty acid oxidation. Mut heterozygosity in mice alters muscle lipid metabolism in vivo, resulting in increased muscle triglyceride accumulation, increased plasma glucose, hyperinsulinemia, and increased body weight after high-fat feeding. Conclusions: Our data indicate that impaired muscle BCAA catabolism may contribute to the development of insulin resistance by perturbing both amino acid and fatty acid metabolism and suggest that targeting BCAA metabolism may hold promise for prevention or treatment of T2D. Keywords: Insulin sensitivity, BCAA, Fatty acid oxidation, TCA cycle

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Effects of genetic variants in ADCY5, GIPR, GCKR and VPS13C on early impairment of glucose and insulin metabolism in children.

    Directory of Open Access Journals (Sweden)

    Jan Windholz

    Full Text Available OBJECTIVE: Recent genome-wide association studies identified novel candidate genes for fasting and 2 h blood glucose and insulin levels in adults. We investigated the role of four of these loci (ADCY5, GIPR, GCKR and VPS13C in early impairment of glucose and insulin metabolism in children. RESEARCH DESIGN AND METHODS: We genotyped four variants (rs2877716; rs1260326; rs10423928; rs17271305 in 638 Caucasian children with detailed metabolic testing including an oGTT and assessed associations with measures of glucose and insulin metabolism (including fasting blood glucose, insulin levels and insulin sensitivity/secretion indices by linear regression analyses adjusted for age, sex, BMI-SDS and pubertal stage. RESULTS: The major allele (C of rs2877716 (ADCY5 was nominally associated with decreased fasting plasma insulin (P = 0.008, peak insulin (P = 0.009 and increased QUICKI (P = 0.016 and Matsuda insulin sensitivity index (P = 0.013. rs17271305 (VPS13C was nominally associated with 2 h blood glucose (P = 0.009, but not with any of the insulin or insulin sensitivity parameters. We found no association of the GIPR and GCKR variants with parameters of glucose and insulin metabolism. None of the variants correlated with anthropometric traits such as height, WHR or BMI-SDS, which excluded potential underlying associations with obesity. CONCLUSIONS: Our data on obese children indicate effects of genetic variation within ADCY5 in early impairment of insulin metabolism and VPS13C in early impairment of blood glucose homeostasis.

  12. 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.

  13. Gut microbiota and metabolic syndrome.

    Science.gov (United States)

    Festi, Davide; Schiumerini, Ramona; Eusebi, Leonardo Henry; Marasco, Giovanni; Taddia, Martina; Colecchia, Antonio

    2014-11-21

    Gut microbiota exerts a significant role in the pathogenesis of the metabolic syndrome, as confirmed by studies conducted both on humans and animal models. Gut microbial composition and functions are strongly influenced by diet. This complex intestinal "superorganism" seems to affect host metabolic balance modulating energy absorption, gut motility, appetite, glucose and lipid metabolism, as well as hepatic fatty storage. An impairment of the fine balance between gut microbes and host's immune system could culminate in the intestinal translocation of bacterial fragments and the development of "metabolic endotoxemia", leading to systemic inflammation and insulin resistance. Diet induced weight-loss and bariatric surgery promote significant changes of gut microbial composition, that seem to affect the success, or the inefficacy, of treatment strategies. Manipulation of gut microbiota through the administration of prebiotics or probiotics could reduce intestinal low grade inflammation and improve gut barrier integrity, thus, ameliorating metabolic balance and promoting weight loss. However, further evidence is needed to better understand their clinical impact and therapeutic use.

  14. BClI polymorphism of the glucocorticoid receptor gene is associated with increased obesity, impaired glucose metabolism and dyslipidaemia in patients with Addison's disease.

    Science.gov (United States)

    Giordano, Roberta; Marzotti, Stefania; Berardelli, Rita; Karamouzis, Ioannis; Brozzetti, Annalisa; D'Angelo, Valentina; Mengozzi, Giulio; Mandrile, Giorgia; Giachino, Daniela; Migliaretti, Giuseppe; Bini, Vittorio; Falorni, Alberto; Ghigo, Ezio; Arvat, Emanuela

    2012-12-01

    Although glucocorticoids are essential for health, several studies have shown that glucocorticoids replacement in Addison's disease might be involved in anthropometric and metabolic impairment, with increased cardiovascular risk, namely if conventional doses are used. As the effects of glucocorticoids are mediated by the glucocorticoid receptor, encoded by NR3C1 gene, different polymorphisms in the NR3C1 gene have been linked to altered glucocorticoid sensitivity in general population as well as in patients with obesity or metabolic syndrome. We investigated the impact of glucocorticoid receptor gene polymorphisms, including the BclI, N363S and ER22/23EK variants, on anthropometric parameters (BMI and waist circumference), metabolic profile (HOMA, OGTT and serum lipids) and ACTH levels in 50 patients with Addison's disease (34 women and 16 men, age 20-82 year) under glucocorticoids replacement. Neither N363S nor ER22/23EK variants were significantly associated with anthropometric, metabolic or hormonal parameters, while patients carrying the homozygous BclI polymorphism GG (n = 4) showed higher (P Addison's disease and may contribute, along with other factors, to the increase in central adiposity, impaired glucose metabolism and dyslipidaemia. © 2012 Blackwell Publishing Ltd.

  15. 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.

  16. 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...

  17. Energy metabolism of thoracic surgical patients in the early postoperative period. Effect of posture.

    Science.gov (United States)

    Brandi, L S; Bertolini, R; Janni, A; Gioia, A; Angeletti, C A

    1996-03-01

    To determine the effect of elective thoracic surgery on energy metabolism and gas exchange and to evaluate whether the 30-degree sitting position would affect these variables. Prospective, unblinded, controlled study. Surgical ICU in a university hospital. Twenty-two adult patients undergoing elective pulmonary resection. Posture change from supine to 30-degree sitting position. Oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory quotient (RQ), and energy expenditure (EE) were measured by means of computerized indirect calorimetry before and after surgery. Heart rate and respiratory frequency were measured continuously during gas exchange measurement. Blood gases were analyzed with an automated blood gas analyzer. Preoperatively, altering position did not affect energy metabolism, gas exchange, and cardiopulmonary variables. Postoperatively, the measured EE was 116% of the expected value. Mean EE and VO2 values for each position were higher than the preoperative values for the corresponding postures (pMean percent increases in EE, VO2, and VCO2 were significantly lower in the 30-degree sitting position than in the supine position (EE: 7.9+/-2.7% vs 14.4+/-2.3%; pexchange for each position were worse than the preoperative values for the corresponding postures (pMean arterial pressure, heart rate, and respiratory frequency for each position were higher than the preoperative values for the corresponding postures (pmean values of these variables occurred between the two positions postoperatively. The early postoperative period of patients undergoing elective thoracic surgery is characterized by a condition of impaired gas exchange and by a hypermetabolic state. Hypermetabolism can be partly mitigated by assuming the 30-degree sitting position.

  18. 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.

  19. Impairment of metabolic capacities in copper and cadmium contaminated wild yellow perch (Perca flavescens)

    International Nuclear Information System (INIS)

    Couture, Patrice; Rajender Kumar, Puja

    2003-01-01

    This study examined variations in resting oxygen consumption rate (ROCR), post-exercise oxygen consumption rate, relative scope for activity (RSA), liver and muscle aerobic and anaerobic capacities (using citrate synthase (CS) and lactate dehydrogenase, respectively, as indicators), and tissue biosynthetic capacities (using nucleoside diphosphate kinase (NDPK) as an indicator), in wild yellow perch from four lakes varying in copper (Cu) and cadmium (Cd) contamination. Liver Cu and Cd concentrations largely reflected environmental contamination and were positively correlated with liver protein concentrations and NDPK activities. Our results suggest that metal contamination leads to an upregulation of liver protein metabolism, presumably at least in part for the purpose of metal detoxification. In contrast, muscle NDPK activities decreased with increasing liver Cd concentrations and NDPK activities. There was a 25% decrease in ROCR for a doubling of liver Cu concentrations and a 42% decrease in RSA for a doubling of liver Cd concentrations in the range studied. Cu contamination was also associated with lower muscle CS activities. Our results support previous findings of impaired aerobic capacities in the muscle of metal-contaminated fish, and demonstrate that this impairment is also reflected in aerobic capacities of whole fish. The evidence presented suggests that mitochondria may be primary targets for inhibition by Cu, and that Cd may reduce gill respiratory capacity. Muscle aerobic and anaerobic capacities were inversely related. This work indicates that metal exposure of wild yellow perch leads to a wide range of disturbances in metabolic capacities

  20. Bace1 activity impairs neuronal glucose metabolism: rescue by beta-hydroxybutyrate and lipoic acid

    Directory of Open Access Journals (Sweden)

    John A Findlay

    2015-10-01

    Full Text Available Glucose hypometabolism and impaired mitochondrial function in neurons have been suggested to play early and perhaps causative roles in Alzheimer’s disease (AD pathogenesis. Activity of the aspartic acid protease, beta-site amyloid precursor protein (APP cleaving enzyme 1 (BACE1, responsible for beta amyloid peptide generation, has recently been demonstrated to modify glucose metabolism. We therefore examined, using a human neuroblastoma (SH-SY5Y cell line, whether increased BACE1 activity is responsible for a reduction in cellular glucose metabolism. Overexpression of active BACE1, but not a protease-dead mutant BACE1, protein in SH-SY5Y cells reduced glucose oxidation and the basal oxygen consumption rate, which was associated with a compensatory increase in glycolysis. Increased BACE1 activity had no effect on the mitochondrial electron transfer process but was found to diminish substrate delivery to the mitochondria by inhibition of key mitochondrial decarboxylation reaction enzymes. This BACE1 activity-dependent deficit in glucose oxidation was alleviated by the presence of beta hydroxybutyrate or α-lipoic acid. Consequently our data indicate that raised cellular BACE1 activity drives reduced glucose oxidation in a human neuronal cell line through impairments in the activity of specific tricarboxylic acid cycle enzymes. Because this bioenergetic deficit is recoverable by neutraceutical compounds we suggest that such agents, perhaps in conjunction with BACE1 inhibitors, may be an effective therapeutic strategy in the early-stage management or treatment of AD.

  1. 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.

  2. Mice with an Oncogenic HRAS Mutation are Resistant to High-Fat Diet-Induced Obesity and Exhibit Impaired Hepatic Energy Homeostasis

    Directory of Open Access Journals (Sweden)

    Daiju Oba

    2018-01-01

    Full Text Available Costello syndrome is a “RASopathy” that is characterized by growth retardation, dysmorphic facial appearance, hypertrophic cardiomyopathy and tumor predisposition. >80% of patients with Costello syndrome harbor a heterozygous germline G12S mutation in HRAS. Altered metabolic regulation has been suspected because patients with Costello syndrome exhibit hypoketotic hypoglycemia and increased resting energy expenditure, and their growth is severely retarded. To examine the mechanisms of energy reprogramming by HRAS activation in vivo, we generated knock-in mice expressing a heterozygous Hras G12S mutation (HrasG12S/+ mice as a mouse model of Costello syndrome. On a high-fat diet, HrasG12S/+ mice developed a lean phenotype with microvesicular hepatic steatosis, resulting in early death compared with wild-type mice. Under starvation conditions, hypoketosis and elevated blood levels of long-chain fatty acylcarnitines were observed, suggesting impaired mitochondrial fatty acid oxidation. Our findings suggest that the oncogenic Hras mutation modulates energy homeostasis in vivo.

  3. 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...

  4. Some considerations of the energy spectrum of odd-odd deformed nuclei; Quelqes considerations sur le spectre d'energie des noyaux impair-impair deformes

    Energy Technology Data Exchange (ETDEWEB)

    Alceanu-G, Pinho de; Picard, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    The odd-odd deformed nuclei are described as a rotator plus two odd nucleons moving in orbitals {omega}{sub p} and {omega}{sub n} of the deformed potential. We investigate the energies and wave functions of the various states of the ({omega}{sub p}, {omega}{sub n}) configurations by calculating and numerically diagonalizing the Hamiltonian matrix (with R.P.C. and residual interactions). The Gallagher-Mosskowski coupling rules ana the abnormal K equals 0 rotational bands are discussed. (authors) [French] Les noyaux impair-impairs deformes sont decrits comme un rotateur plus deux nucleons non apparies dans les orbites {omega}{sub p} et {omega}{sub n} du potentiel deforme. Nous etudions le spectre d'energie et les fonctions d'onde des configurations ({omega}{sub p}, {omega}{sub n}) en tenant compte de l'interaction particule-rotation et de la force residuelle entre les deux nucleons celibataires.

  5. 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.

  6. 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.

  7. A structured approach to the study of metabolic control principles in intact and impaired mitochondria.

    Science.gov (United States)

    Huber, Heinrich J; Connolly, Niamh M C; Dussmann, Heiko; Prehn, Jochen H M

    2012-03-01

    We devised an approach to extract control principles of cellular bioenergetics for intact and impaired mitochondria from ODE-based models and applied it to a recently established bioenergetic model of cancer cells. The approach used two methods for varying ODE model parameters to determine those model components that, either alone or in combination with other components, most decisively regulated bioenergetic state variables. We found that, while polarisation of the mitochondrial membrane potential (ΔΨ(m)) and, therefore, the protomotive force were critically determined by respiratory complex I activity in healthy mitochondria, complex III activity was dominant for ΔΨ(m) during conditions of cytochrome-c deficiency. As a further important result, cellular bioenergetics in healthy, ATP-producing mitochondria was regulated by three parameter clusters that describe (1) mitochondrial respiration, (2) ATP production and consumption and (3) coupling of ATP-production and respiration. These parameter clusters resembled metabolic blocks and their intermediaries from top-down control analyses. However, parameter clusters changed significantly when cells changed from low to high ATP levels or when mitochondria were considered to be impaired by loss of cytochrome-c. This change suggests that the assumption of static metabolic blocks by conventional top-down control analyses is not valid under these conditions. Our approach is complementary to both ODE and top-down control analysis approaches and allows a better insight into cellular bioenergetics and its pathological alterations.

  8. 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.

  9. High sucrose consumption induces memory impairment in rats associated with electrophysiological modifications but not with metabolic changes in the hippocampus.

    Science.gov (United States)

    Lemos, C; Rial, D; Gonçalves, F Q; Pires, J; Silva, H B; Matheus, F C; da Silva, A C; Marques, J M; Rodrigues, R J; Jarak, I; Prediger, R D; Reis, F; Carvalho, R A; Pereira, F C; Cunha, R A

    2016-02-19

    High sugar consumption is a risk factor for metabolic disturbances leading to memory impairment. Thus, rats subject to high sucrose intake (HSu) develop a metabolic syndrome and display memory deficits. We now investigated if these HSu-induced memory deficits were associated with metabolic and electrophysiological alterations in the hippocampus. Male Wistar rats were submitted for 9 weeks to a sucrose-rich diet (35% sucrose solution) and subsequently to a battery of behavioral tests; after sacrifice, their hippocampi were collected for ex vivo high-resolution magic angle spinning (HRMAS) metabolic characterization and electrophysiological extracellular recordings in slices. HSu rats displayed a decreased memory performance (object displacement and novel object recognition tasks) and helpless behavior (forced swimming test), without altered locomotion (open field). HRMAS analysis indicated a similar hippocampal metabolic profile of HSu and control rats. HSu rats also displayed no change of synaptic transmission and plasticity (long-term potentiation) in hippocampal Schaffer fibers-CA1 pyramid synapses, but had decreased amplitude of long-term depression in the temporoammonic (TA) pathway. Furthermore, HSu rats had an increased density of inhibitory adenosine A1 receptors (A1R), that translated into a greater potency of A1R in Schaffer fiber synapses, but not in the TA pathway, whereas the endogenous activation of A1R in HSu rats was preserved in the TA pathway but abolished in Schaffer fiber synapses. These results suggest that HSu triggers a hippocampal-dependent memory impairment that is not associated with altered hippocampal metabolism but is probably related to modified synaptic plasticity in hippocampal TA synapses. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. 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.

  11. 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

  12. 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.

  13. Metabolic changes in early lactation and impaired reproductive performance in dairy cows.

    NARCIS (Netherlands)

    Jorritsma, R.; Wensing, T.; Kruip, T.A.M.; Vos, P.L.A.M.; Noordhuizen, J.P.T.M.

    2003-01-01

    This review addresses the suggestion that the decline in dairy reproductive performance, as increasingly observed these days, may be due to a hampered process of metabolic adaptation in early lactating cows. In our opinion, adaptation to the negative energy balance is a gradual process. Because

  14. Effect of Tiaoxin Recipe (调心方) on Spatial Memory and Energy Metabolism of Oxidation Injured Alzheimer's Disease Rats

    Institute of Scientific and Technical Information of China (English)

    邱宏; 金国琴; 赵伟康; 张学礼

    2003-01-01

    Objective: To observe the effect of Tiaoxin Recipe (TXR) on the spatial memory, brain mitochondrial energy metabolism of oxidation injured Alzheimer's disease (AD) rats, and to explore the mechanism of TXR in treating AD. Methods: Eighty-eight SD rats were randomly divided into five groups (normal group, operative group, "AD" model group,TXR group and Aricept group). An oxygen free radical generation system (dihydroxy fumaric acid-trichloroferric-adenosine diphosphate, DHF-FeCl3-ADP) was used to create oxidation injured rat models mimic to AD; spatial learning and memory impairment (Morris water maze method), the activity of Succinate-oxidase, NADH-oxidase, CytC-oxidase (Clark oxygen electrode method) and the expression of cytochrome oxidase (CO)ⅡmRNA (in situ hybridization method) were observed. Results: Compared with the normal group, the spatial memory, activity of CytC-oxidase and COⅡmRNA expression of oxidation injured "AD" rats were obviously decreased; TXR, however, could improve these functions in "AD" rat models obviously. Conclusion: The mechanism of the action of TXR in treating AD was partly related to its effect on anti-oxidation which could improve brain mitochondrial energy metabolism.

  15. 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 ...

  16. 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 ...

  17. Expression of genes involved in lipid metabolism in men with impaired glucose tolerance : impact of insulin stimulation and weight loss

    NARCIS (Netherlands)

    Konings, E.; Corpeleijn, E.; Bouwman, F.G.; Mariman, E.C.; Blaak, E.E.

    2010-01-01

    Background: The impaired glucose tolerance (IGT) state is characterized by insulin resistance. Disturbances in fatty acid (FA) metabolism may underlie this reduced insulin sensitivity. The aim of this study was to investigate whether the prediabetic state is accompanied by changes in the expression

  18. 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 ...

  19. 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.

  20. Fluorescence lifetime microscopy of NADH distinguishes alterations in cerebral metabolism in vivo.

    Science.gov (United States)

    Yaseen, Mohammad A; Sutin, Jason; Wu, Weicheng; Fu, Buyin; Uhlirova, Hana; Devor, Anna; Boas, David A; Sakadžić, Sava

    2017-05-01

    Evaluating cerebral energy metabolism at microscopic resolution is important for comprehensively understanding healthy brain function and its pathological alterations. Here, we resolve specific alterations in cerebral metabolism in vivo in Sprague Dawley rats utilizing minimally-invasive 2-photon fluorescence lifetime imaging (2P-FLIM) measurements of reduced nicotinamide adenine dinucleotide (NADH) fluorescence. Time-resolved fluorescence lifetime measurements enable distinction of different components contributing to NADH autofluorescence. Ostensibly, these components indicate different enzyme-bound formulations of NADH. We observed distinct variations in the relative proportions of these components before and after pharmacological-induced impairments to several reactions involved in glycolytic and oxidative metabolism. Classification models were developed with the experimental data and used to predict the metabolic impairments induced during separate experiments involving bicuculline-induced seizures. The models consistently predicted that prolonged focal seizure activity results in impaired activity in the electron transport chain, likely the consequence of inadequate oxygen supply. 2P-FLIM observations of cerebral NADH will help advance our understanding of cerebral energetics at a microscopic scale. Such knowledge will aid in our evaluation of healthy and diseased cerebral physiology and guide diagnostic and therapeutic strategies that target cerebral energetics.

  1. LKB1 promotes metabolic flexibility in response to energy stress.

    Science.gov (United States)

    Parker, Seth J; Svensson, Robert U; Divakaruni, Ajit S; Lefebvre, Austin E; Murphy, Anne N; Shaw, Reuben J; Metallo, Christian M

    2017-09-01

    The Liver Kinase B1 (LKB1) tumor suppressor acts as a metabolic energy sensor to regulate AMP-activated protein kinase (AMPK) signaling and is commonly mutated in various cancers, including non-small cell lung cancer (NSCLC). Tumor cells deficient in LKB1 may be uniquely sensitized to metabolic stresses, which may offer a therapeutic window in oncology. To address this question we have explored how functional LKB1 impacts the metabolism of NSCLC cells using 13 C metabolic flux analysis. Isogenic NSCLC cells expressing functional LKB1 exhibited higher flux through oxidative mitochondrial pathways compared to those deficient in LKB1. Re-expression of LKB1 also increased the capacity of cells to oxidize major mitochondrial substrates, including pyruvate, fatty acids, and glutamine. Furthermore, LKB1 expression promoted an adaptive response to energy stress induced by anchorage-independent growth. Finally, this diminished adaptability sensitized LKB1-deficient cells to combinatorial inhibition of mitochondrial complex I and glutaminase. Together, our data implicate LKB1 as a major regulator of adaptive metabolic reprogramming and suggest synergistic pharmacological strategies for mitigating LKB1-deficient NSCLC tumor growth. Copyright © 2016. Published by Elsevier Inc.

  2. Loss of Mitochondrial Function Impairs Lysosomes.

    Science.gov (United States)

    Demers-Lamarche, Julie; Guillebaud, Gérald; Tlili, Mouna; Todkar, Kiran; Bélanger, Noémie; Grondin, Martine; Nguyen, Angela P; Michel, Jennifer; Germain, Marc

    2016-05-06

    Alterations in mitochondrial function, as observed in neurodegenerative diseases, lead to disrupted energy metabolism and production of damaging reactive oxygen species. Here, we demonstrate that mitochondrial dysfunction also disrupts the structure and function of lysosomes, the main degradation and recycling organelle. Specifically, inhibition of mitochondrial function, following deletion of the mitochondrial protein AIF, OPA1, or PINK1, as well as chemical inhibition of the electron transport chain, impaired lysosomal activity and caused the appearance of large lysosomal vacuoles. Importantly, our results show that lysosomal impairment is dependent on reactive oxygen species. Given that alterations in both mitochondrial function and lysosomal activity are key features of neurodegenerative diseases, this work provides important insights into the etiology of neurodegenerative diseases. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. One-carbon metabolism, cognitive impairment and CSF measures of Alzheimer pathology: homocysteine and beyond.

    Science.gov (United States)

    Dayon, Loïc; Guiraud, Seu Ping; Corthésy, John; Da Silva, Laeticia; Migliavacca, Eugenia; Tautvydaitė, Domilė; Oikonomidi, Aikaterini; Moullet, Barbara; Henry, Hugues; Métairon, Sylviane; Marquis, Julien; Descombes, Patrick; Collino, Sebastiano; Martin, François-Pierre J; Montoliu, Ivan; Kussmann, Martin; Wojcik, Jérôme; Bowman, Gene L; Popp, Julius

    2017-06-17

    Hyperhomocysteinemia is a risk factor for cognitive decline and dementia, including Alzheimer disease (AD). Homocysteine (Hcy) is a sulfur-containing amino acid and metabolite of the methionine pathway. The interrelated methionine, purine, and thymidylate cycles constitute the one-carbon metabolism that plays a critical role in the synthesis of DNA, neurotransmitters, phospholipids, and myelin. In this study, we tested the hypothesis that one-carbon metabolites beyond Hcy are relevant to cognitive function and cerebrospinal fluid (CSF) measures of AD pathology in older adults. Cross-sectional analysis was performed on matched CSF and plasma collected from 120 older community-dwelling adults with (n = 72) or without (n = 48) cognitive impairment. Liquid chromatography-mass spectrometry was performed to quantify one-carbon metabolites and their cofactors. Least absolute shrinkage and selection operator (LASSO) regression was initially applied to clinical and biomarker measures that generate the highest diagnostic accuracy of a priori-defined cognitive impairment (Clinical Dementia Rating-based) and AD pathology (i.e., CSF tau phosphorylated at threonine 181 [p-tau181]/β-Amyloid 1-42 peptide chain [Aβ 1-42 ] >0.0779) to establish a reference benchmark. Two other LASSO-determined models were generated that included the one-carbon metabolites in CSF and then plasma. Correlations of CSF and plasma one-carbon metabolites with CSF amyloid and tau were explored. LASSO-determined models were stratified by apolipoprotein E (APOE) ε4 carrier status. The diagnostic accuracy of cognitive impairment for the reference model was 80.8% and included age, years of education, Aβ 1-42 , tau, and p-tau181. A model including CSF cystathionine, methionine, S-adenosyl-L-homocysteine (SAH), S-adenosylmethionine (SAM), serine, cysteine, and 5-methyltetrahydrofolate (5-MTHF) improved the diagnostic accuracy to 87.4%. A second model derived from plasma included cystathionine

  4. Individual cerebral metabolic deficits in Alzheimer's disease and amnestic mild cognitive impairment: an FDG PET study

    International Nuclear Information System (INIS)

    Del Sole, Angelo; Lecchi, Michela; Lucignani, Giovanni; Clerici, Francesca; Mariani, Claudio; Maggiore, Laura; Chiti, Arturo; Mosconi, Lisa

    2008-01-01

    The purpose of the study was the identification of group and individual subject patterns of cerebral glucose metabolism (CMRGlu) in patients with Alzheimer's disease (AD) and with amnestic mild cognitive impairment (aMCI). [ 18 F]fluorodeoxyglucose positron emission tomography (PET) studies and neuropsychological tests were performed in 16 aMCI patients (ten women, age 75 ± 8 years) and in 14 AD patients (ten women, age 75 ± 9 years). Comparisons between patient subgroups and with a control population were performed using Statistical Parametric Mapping. Clusters of low CMRGlu were observed bilaterally in the posterior cingulate cortex (PCC), in the precuneus, in the inferior parietal lobule and middle temporal gyrus of AD patients. In aMCI patients, reduced CMRGlu was found only in PCC. Areas of low CMRGlu in PCC were wider in AD compared to aMCI and extended to the precuneus, while low CMRGlu was found in the lateral parietal cortex in AD but not in aMCI patients. Individual subject pattern analysis revealed that 86% of AD patients had low CMRGlu in the PCC (including the precuneus in 71%), 71% in the temporal cortex, 64% in the parietal cortex and 35% in the frontal cortex. Among the aMCI patients, 56% had low CMRGlu in the PCC, 44% in the temporal cortex, 18% in the frontal cortex and none in the parietal cortex. This study demonstrates that both AD and aMCI patients have highly heterogeneous metabolic impairment. This potential of individual metabolic PET imaging in patients with AD and aMCI may allow timely identification of brain damage on individual basis and possibly help planning tailored early interventions. (orig.)

  5. Cognitive impairment and Alzheimer’s disease: Links with oxidative stress and cholesterol metabolism

    Directory of Open Access Journals (Sweden)

    Alejandra Sekler

    2008-08-01

    Full Text Available Alejandra Sekler1,2, José M Jiménez2, Leonel Rojo2, Edgard Pastene3, Patricio Fuentes4, Andrea Slachevsky4, Ricardo B Maccioni1,21Center of Cognitive Neurosciences, International Center for Biomedicine (ICC, Santiago, Chile; 2Laboratory of Cellular, Molecular Biology and Neurosciences, Faculty of Sciences, Universidad de Chile, Santiago, Chile; 3Department of Pharmacy, Faculty of Pharmacy, University of Concepcion, Concepción, Chile; 4Unidad de Neurología Cognitiva y Demencias, Servicio de Neurología, Hospital del Salvador, Santiago, ChileAbstract: Oxidative stress has been implicated in the progression of a number of neurodegenerative diseases, including Alzheimer’s disease (AD, Parkinson’s disease and amyotrophic lateral sclerosis. We carried out an in-depth study of cognitive impairment and its relationships with oxidative stress markers such as ferric-reducing ability of plasma (FRAP, plasma malondialdehyde and total antioxidative capacity (TAC, as well as cholesterol parameters, in two subsets of subjects, AD patients (n = 59 and a control group of neurologically normal subjects (n = 29, attending the University Hospital Salvador in Santiago, Chile. Cognitive impairment was assessed by a set of neuropsychological tests (Mini-Mental State Examination, Boston Naming Test, Ideomotor Praxia by imitation, Semantic Verbal Fluency of animals or words with initial A, Test of Memory Alteration, Frontal Assessment Battery, while the levels of those oxidative stress markers and cholesterol metabolism parameters were determined according with standard bioassays in fresh plasma samples of the two subgroups of patients. No significant differences were observed when the cholesterol parameters (low-, high-density lipoprotein, total cholesterol of the AD group were compared with normal controls. Interestingly, a correlation was evidenced when the levels of cognitive impairment were analyzed with respect to the plasma antioxidant capacity (AOC of

  6. The Relationships between Metabolic Disorders (Hypertension, Dyslipidemia, and Impaired Glucose Tolerance) and Computed Tomography-Based Indices of Hepatic Steatosis or Visceral Fat Accumulation in Middle-Aged Japanese Men.

    Science.gov (United States)

    Fujibayashi, Kazutoshi; Gunji, Toshiaki; Yokokawa, Hirohide; Naito, Toshio; Sasabe, Noriko; Okumura, Mitsue; Iijima, Kimiko; Shibuya, Katsuhiko; Hisaoka, Teruhiko; Fukuda, Hiroshi

    2016-01-01

    Most studies on the relationships between metabolic disorders (hypertension, dyslipidemia, and impaired glucose tolerance) and hepatic steatosis (HS) or visceral fat accumulation (VFA) have been cross-sectional, and thus, these relationships remain unclear. We conducted a retrospective cohort study to clarify the relationships between components of metabolic disorders and HS/VFA. The participants were 615 middle-aged men who were free from serious liver disorders, diabetes, and HS/VFA and underwent multiple general health check-ups at our institution between 2009 and 2013. The data from the initial and final check-ups were used. HS and VFA were assessed by computed tomography. HS was defined as a liver to spleen attenuation ratio of ≤1.0. VFA was defined as a visceral fat cross-sectional area of ≥100 cm2 at the level of the navel. Metabolic disorders were defined using Japan's metabolic syndrome diagnostic criteria. The participants were divided into four groups based on the presence (+) or absence (-) of HS/VFA. The onset rates of each metabolic disorder were compared among the four groups. Among the participants, 521, 55, 24, and 15 were classified as HS(-)/VFA(-), HS(-)/VFA(+), HS(+)/VFA(-), and HS(+)/VFA(+), respectively, at the end of the study. Impaired glucose tolerance was more common among the participants that exhibited HS or VFA (p = 0.05). On the other hand, dyslipidemia was more common among the participants that displayed VFA (p = 0.01). It is likely that VFA is associated with impaired glucose tolerance and dyslipidemia, while HS might be associated with impaired glucose tolerance. Unfortunately, our study failed to detect associations between HS/VFA and metabolic disorders due to the low number of subjects that exhibited fat accumulation. Although our observational study had major limitations, we consider that it obtained some interesting results. HS and VFA might affect different metabolic disorders. Further large-scale longitudinal studies are

  7. The Relationships between Metabolic Disorders (Hypertension, Dyslipidemia, and Impaired Glucose Tolerance and Computed Tomography-Based Indices of Hepatic Steatosis or Visceral Fat Accumulation in Middle-Aged Japanese Men.

    Directory of Open Access Journals (Sweden)

    Kazutoshi Fujibayashi

    Full Text Available Most studies on the relationships between metabolic disorders (hypertension, dyslipidemia, and impaired glucose tolerance and hepatic steatosis (HS or visceral fat accumulation (VFA have been cross-sectional, and thus, these relationships remain unclear. We conducted a retrospective cohort study to clarify the relationships between components of metabolic disorders and HS/VFA.The participants were 615 middle-aged men who were free from serious liver disorders, diabetes, and HS/VFA and underwent multiple general health check-ups at our institution between 2009 and 2013. The data from the initial and final check-ups were used. HS and VFA were assessed by computed tomography. HS was defined as a liver to spleen attenuation ratio of ≤1.0. VFA was defined as a visceral fat cross-sectional area of ≥100 cm2 at the level of the navel. Metabolic disorders were defined using Japan's metabolic syndrome diagnostic criteria. The participants were divided into four groups based on the presence (+ or absence (- of HS/VFA. The onset rates of each metabolic disorder were compared among the four groups.Among the participants, 521, 55, 24, and 15 were classified as HS(-/VFA(-, HS(-/VFA(+, HS(+/VFA(-, and HS(+/VFA(+, respectively, at the end of the study. Impaired glucose tolerance was more common among the participants that exhibited HS or VFA (p = 0.05. On the other hand, dyslipidemia was more common among the participants that displayed VFA (p = 0.01.It is likely that VFA is associated with impaired glucose tolerance and dyslipidemia, while HS might be associated with impaired glucose tolerance. Unfortunately, our study failed to detect associations between HS/VFA and metabolic disorders due to the low number of subjects that exhibited fat accumulation. Although our observational study had major limitations, we consider that it obtained some interesting results. HS and VFA might affect different metabolic disorders. Further large-scale longitudinal studies

  8. Atgl gene deletion predisposes to proximal tubule damage by impairing the fatty acid metabolism

    International Nuclear Information System (INIS)

    Chen, Wen; Zhang, Qiong; Cheng, Shiwu; Huang, Jie; Diao, Ge; Han, Jian

    2017-01-01

    Fibrosis is the final common pathway of chronic kidney disease (CKD). Normal lipid metabolism is integral to renal physiology, and disturbances of renal lipid metabolism are increasingly being linked with CKD, including the fibrosis. Adipose triglyceride lipase (ATGL) is the rate-limiting enzyme of lipolysis. In the present study, we used Atgl −/− mice to investigate whether ATGL played a role in the regulation of proximal convoluted tubule (PCT) lipid metabolism and renal fibrosis development. ATGL deficiency led to lipid vacuolation of PCT and tubulointerstitial fibrosis, accompanied by massive albuminuria and decreased creatinine clearance rate (Ccr). In vitro experiments indicated that inhibition of ATGL in proximal tubular cell line HK-2 promoted intracellular lipid deposition, reactive oxygen species (ROS) accumulation and cell apoptosis. Both in vitro and in vivo experiments showed that ATGL inhibition decreased the renal peroxisome proliferator-activated receptorα(PPARα) expression, which implied the suppressed lipid metabolism. The antioxidant N-acetylcysteine (NAC) could partially reverse the effect of ROS accumulation and cell apoptosis, but could not restore the PPARαdecrease. These data raise the possibility that ATGL deficiency could impair the renal fatty acid metabolism though inhibiting PPARαexpression, which may lead to lipid deposition and cell apoptosis of PCT, and finally contribute to the renal fibrosis and dysfunction. - Highlights: • Atgl −/− mice develop tubulointerstitial damage and renal dysfunction. • ATGL deficiency results in lipid accumulation and apoptosis of proximal tubular cells. • ROS scavenger alleviates the ATGL-knockdown mediated lipid accumulation and apoptosis. • PPARαdown-regulation is the reason of ROS elevating in ATGL-knockdown HK-2 cells.

  9. The metabolic effects of diuron in the rat liver.

    Science.gov (United States)

    da Silva Simões, Mellina; Bracht, Lívia; Parizotto, Angela Valderrama; Comar, Jurandir Fernando; Peralta, Rosane Marina; Bracht, Adelar

    2017-09-01

    A systematic study on the effects of diuron on the hepatic metabolism was conducted with emphasis on parameters linked to energy metabolism. The experimental system was the isolated perfused rat liver. The results demonstrate that diuron inhibited biosynthesis (gluconeogenesis) and ammonia detoxification, which are dependent of ATP generated within the mitochondria. Conversely, it stimulated glycolysis and fructolysis, which are compensatory phenomena for an inhibited mitochondrial ATP generation. Furthermore, diuron diminished the cellular ATP content under conditions where the mitochondrial respiratory chain was the only source of this compound. Besides the lack of circulating glucose due to gluconeogenesis inhibition, one can expect metabolic acidosis due to excess lactate production, impairment of ammonia detoxification and cell damage due to a deficient maintenance of its homeostasis. Some of the general signs of toxicity that were observed in diuron-treated rats can be attributed, partly at least, to the effects of the herbicide on energy metabolism. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Influence of high carbohydrate versus high fat diet in ozone induced pulmonary injury and systemic metabolic impairment in a Brown Norway (BN) rat model of healthy aging

    Science.gov (United States)

    Rationale: Air pollution has been recently linked to the increased prevalence of metabolic syndrome. It has been postulated that dietary risk factors might exacerbate air pollution-induced metabolic impairment. We have recently reported that ozone exposure induces acute systemic ...

  11. Exercise reveals impairments in left ventricular systolic function in patients with metabolic syndrome.

    Science.gov (United States)

    Fournier, Sara B; Reger, Brian L; Donley, David A; Bonner, Daniel E; Warden, Bradford E; Gharib, Wissam; Failinger, Conard F; Olfert, Melissa D; Frisbee, Jefferson C; Olfert, I Mark; Chantler, Paul D

    2014-01-01

    Metabolic syndrome (MetS) is the manifestation of a cluster of cardiovascular risk factors and is associated with a threefold increase in the risk of cardiovascular morbidity and mortality, which is suggested to be mediated, in part, by resting left ventricular (LV) systolic dysfunction. However, to what extent resting LV systolic function is impaired in MetS is controversial, and there are no data indicating whether LV systolic function is impaired during exercise. Accordingly, the objective of this study was to examine comprehensively the LV and arterial responses to exercise in individuals with MetS without diabetes and/or overt cardiovascular disease in comparison to a healthy control population. Cardiovascular function was characterized using Doppler echocardiography and gas exchange in individuals with MetS (n = 27) versus healthy control subjects (n = 20) at rest and during peak exercise. At rest, individuals with MetS displayed normal LV systolic function but reduced LV diastolic function compared with healthy control subjects. During peak exercise, individuals with MetS had impaired contractility, pump performance and vasodilator reserve capacity versus control subjects. A blunted contractile reserve response resulted in diminished arterial-ventricular coupling reserve and limited aerobic capacity in individuals with MetS versus control subjects. These findings are of clinical importance, because they provide insight into the pathophysiological changes in MetS that may predispose this population of individuals to an increased risk of cardiovascular morbidity and mortality.

  12. PPAR ligands improve impaired metabolic pathways in fetal hearts of diabetic rats.

    Science.gov (United States)

    Kurtz, Melisa; Capobianco, Evangelina; Martinez, Nora; Roberti, Sabrina Lorena; Arany, Edith; Jawerbaum, Alicia

    2014-10-01

    In maternal diabetes, the fetal heart can be structurally and functionally affected. Maternal diets enriched in certain unsaturated fatty acids can activate the nuclear receptors peroxisome proliferator-activated receptors (PPARs) and regulate metabolic and anti-inflammatory pathways during development. Our aim was to investigate whether PPARα expression, lipid metabolism, lipoperoxidation, and nitric oxide (NO) production are altered in the fetal hearts of diabetic rats, and to analyze the putative effects of in vivo PPAR activation on these parameters. We found decreased PPARα expression in the hearts of male but not female fetuses of diabetic rats when compared with controls. Fetal treatments with the PPARα ligand leukotriene B4 upregulated the expression of PPARα and target genes involved in fatty acid oxidation in the fetal hearts. Increased concentrations of triglycerides, cholesterol, and phospholipids were found in the hearts of fetuses of diabetic rats. Maternal treatments with diets supplemented with 6% olive oil or 6% safflower oil, enriched in unsaturated fatty acids that can activate PPARs, led to few changes in lipid concentrations, but up-regulated PPARα expression in fetal hearts. NO production, which was increased in the hearts of male and female fetuses in the diabetic group, and lipoperoxidation, which was increased in the hearts of male fetuses in the diabetic group, was reduced by the maternal treatments supplemented with safflower oil. In conclusion, impaired PPARα expression, altered lipid metabolism, and increased oxidative and nitridergic pathways were evidenced in hearts of fetuses of diabetic rats and were regulated in a gender-dependent manner by treatments enriched with PPAR ligands. © 2014 Society for Endocrinology.

  13. 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.

  14. 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.

  15. 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.

  16. Role of NAD, Oxidative Stress, and Tryptophan Metabolism in Autism Spectrum Disorders

    Directory of Open Access Journals (Sweden)

    Musthafa Mohamed Essa

    2013-01-01

    Full Text Available Autism spectrum disorder (ASD is a pervasive neuro-developmental disorder characterized by impaired social interaction, reduced/absent verbal and non-verbal communication, and repetitive behavior during early childhood. The etiology of this developmental disorder is poorly understood, and no biomarkers have been identified. Identification of novel biochemical markers related to autism would be advantageous for earlier clinical diagnosis and intervention. Studies suggest that oxidative stress-induced mechanisms and reduced antioxidant defense, mitochondrial dysfunction, and impaired energy metabolism (NAD + , NADH, ATP, pyruvate, and lactate, are major causes of ASD. This review provides renewed insight regarding current autism research related to oxidative stress, mitochondrial dysfunction, and altered tryptophan metabolism in ASD.

  17. 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.

  18. Expression changes of hippocampal energy metabolism enzymes contribute to behavioural abnormalities during chronic morphine treatment

    Institute of Scientific and Technical Information of China (English)

    Xiao-Lan Chen; Jing-Gen Liu; Gang Lu; Ying-Xia Gong; Liang-Cai Zhao; Jie Chen; Zhi-Qiang Chi; Yi-Ming Yang; Zhong Chen; Qing-lin Li

    2007-01-01

    Dependence and impairment of learning and memory are two well-established features caused by abused drugs such as opioids. The hippocampus is an important region associated with both drug dependence and learning and memory. However, the molecular events in hippocampus following exposure to abused drugs such as opioids are not well understood. Here we examined the effect of chronic morphine treatment on hippocampal protein expression by proteomic analyses. We found that chronic exposure of mice to morphine for 10 days produced robust morphine withdrawal jumping and memory impairment, and also resulted in a significant downregulation of hippocampal protein levels of three metabolic enzymes, including Fe-S protein 1 of NADH dehydrogenase, dihydrolipoamide acetyltransferase or E2 component of the pyruvate dehydrogenase complex and lactate dehydrogenase 2. Further real-time quantitative PCR analyses confirmed that the levels of the corresponding mRNAs were also remarkably reduced. Consistent with these findings, lower ATP levels and an impaired ability to convert glucose into ATP were also observed in the hippocampus of chronically treated mice. Opioid antagonist naltrexone administrated concomitantly with morphine significantly suppressed morphine withdrawal jumping and reversed the downregulation of these proteins. Acute exposure to morphine also produced robust morphine withdrawal jumping and significant memory impairment, but failed to decrease the expression of these three proteins. Intrahippocampal injection of D-glucose before morphine administration significantly enhanced ATP levels and suppressed morphine withdrawal jumping and memory impairment in acute morphine-treated but not in chronic morphine-treated mice. Intraperitoneal injection of high dose of D-glucose shows a similar effect on morphine-induced withdrawal jumping as the central treatment. Taken together, our results suggest that reduced expression of the three metabolic enzymes in the hippocampus as

  19. 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.

  20. 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.

  1. 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.

  2. Valsartan Improves β-Cell Function and Insulin Sensitivity in Subjects With Impaired Glucose Metabolism

    Science.gov (United States)

    van der Zijl, Nynke J.; Moors, Chantalle C.M.; Goossens, Gijs H.; Hermans, Marc M.H.; Blaak, Ellen E.; Diamant, Michaela

    2011-01-01

    OBJECTIVE Recently, the Nateglinide and Valsartan in Impaired Glucose Tolerance Outcomes Research Trial demonstrated that treatment with the angiotensin receptor blocker (ARB) valsartan for 5 years resulted in a relative reduction of 14% in the incidence of type 2 diabetes in subjects with impaired glucose metabolism (IGM). We investigated whether improvements in β-cell function and/or insulin sensitivity underlie these preventive effects of the ARB valsartan in the onset of type 2 diabetes. RESEARCH DESIGN AND METHODS In this randomized controlled, double-blind, two-center study, the effects of 26 weeks of valsartan (320 mg daily; n = 40) or placebo (n = 39) on β-cell function and insulin sensitivity were assessed in subjects with impaired fasting glucose and/or impaired glucose tolerance, using a combined hyperinsulinemic-euglycemic and hyperglycemic clamp with subsequent arginine stimulation and a 2-h 75-g oral glucose tolerance test (OGTT). Treatment effects were analyzed using ANCOVA, adjusting for center, glucometabolic status, and sex. RESULTS Valsartan increased first-phase (P = 0.028) and second-phase (P = 0.002) glucose-stimulated insulin secretion compared with placebo, whereas the enhanced arginine-stimulated insulin secretion was comparable between groups (P = 0.25). In addition, valsartan increased the OGTT-derived insulinogenic index (representing first-phase insulin secretion after an oral glucose load; P = 0.027). Clamp-derived insulin sensitivity was significantly increased with valsartan compared with placebo (P = 0.049). Valsartan treatment significantly decreased systolic and diastolic blood pressure compared with placebo (P valsartan treatment increased glucose-stimulated insulin release and insulin sensitivity in normotensive subjects with IGM. These findings may partly explain the beneficial effects of valsartan in the reduced incidence of type 2 diabetes. PMID:21330640

  3. Effects of ovariectomy and exercise training intensity on energy substrate and hepatic lipid metabolism, and spontaneous physical activity in mice.

    Science.gov (United States)

    Tuazon, Marc A; Campbell, Sara C; Klein, Dylan J; Shapses, Sue A; Anacker, Keith R; Anthony, Tracy G; Uzumcu, Mehmet; Henderson, Gregory C

    2018-06-01

    Menopause is associated with fatty liver, glucose dysregulation, increased body fat, and impaired bone quality. Previously, it was demonstrated that single sessions of high-intensity interval exercise (HIIE) are more effective than distance- and duration-matched continuous exercise (CE) on altering hepatic triglyceride (TG) metabolism and very-low density lipoprotein-TG (VLDL-TG) secretion. Six weeks training using these modalities was examined for effects on hepatic TG metabolism/secretion, glucose tolerance, body composition, and bone mineral density (BMD) in ovariectomized (OVX) and sham-operated (SHAM) mice. OVX and SHAM were assigned to distance- and duration-matched CE and HIIE, or sedentary control. Energy expenditure during exercise was confirmed to be identical between CE and HIIE and both similarly reduced post-exercise absolute carbohydrate oxidation and spontaneous physical activity (SPA). OVX vs. SHAM displayed impaired glucose tolerance and greater body fat despite lower hepatic TG, and these outcomes were not affected by training. Only HIIE increased hepatic AMPK in OVX and SHAM, but neither training type impacted VLDL-TG secretion. As expected, BMD was lower in OVX, and training did not affect long bones. The results reveal intensity-dependent effects on hepatic AMPK expression and general exercise effects on subsequent SPA and substrate oxidation that is independent of estrogen status. These findings support the notion that HIIE can impact aspects of liver physiology in females while the effects of exercise on whole body substrate selection appear to be independent of training intensity. However, neither exercise approach mitigated the impairment in glucose tolerance and elevated body fat occurring in OVX mice. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Impaired insulin action in the human brain: causes and metabolic consequences.

    Science.gov (United States)

    Heni, Martin; Kullmann, Stephanie; Preissl, Hubert; Fritsche, Andreas; Häring, Hans-Ulrich

    2015-12-01

    Over the past few years, evidence has accumulated that the human brain is an insulin-sensitive organ. Insulin regulates activity in a limited number of specific brain areas that are important for memory, reward, eating behaviour and the regulation of whole-body metabolism. Accordingly, insulin in the brain modulates cognition, food intake and body weight as well as whole-body glucose, energy and lipid metabolism. However, brain imaging studies have revealed that not everybody responds equally to insulin and that a substantial number of people are brain insulin resistant. In this Review, we provide an overview of the effects of insulin in the brain in humans and the relevance of the effects for physiology. We present emerging evidence for insulin resistance of the human brain. Factors associated with brain insulin resistance such as obesity and increasing age, as well as possible pathogenic factors such as visceral fat, saturated fatty acids, alterations at the blood-brain barrier and certain genetic polymorphisms, are reviewed. In particular, the metabolic consequences of brain insulin resistance are discussed and possible future approaches to overcome brain insulin resistance and thereby prevent or treat obesity and type 2 diabetes mellitus are outlined.

  5. Regulation of longevity by FGF21: Interaction between energy metabolism and stress responses.

    Science.gov (United States)

    Salminen, Antero; Kaarniranta, Kai; Kauppinen, Anu

    2017-08-01

    Fibroblast growth factor 21 (FGF21) is a hormone-like member of FGF family which controls metabolic multiorgan crosstalk enhancing energy expenditure through glucose and lipid metabolism. In addition, FGF21 acts as a stress hormone induced by endoplasmic reticulum stress and dysfunctions of mitochondria and autophagy in several tissues. FGF21 also controls stress responses and metabolism by modulating the functions of somatotropic axis and hypothalamic-pituitary-adrenal (HPA) pathway. FGF21 is a potent longevity factor coordinating interactions between energy metabolism and stress responses. Recent studies have revealed that FGF21 treatment can alleviate many age-related metabolic disorders, e.g. atherosclerosis, obesity, type 2 diabetes, and some cardiovascular diseases. In addition, transgenic mice overexpressing FGF21 have an extended lifespan. However, chronic metabolic and stress-related disorders involving inflammatory responses can provoke FGF21 resistance and thus disturb healthy aging process. First, we will describe the role of FGF21 in interorgan energy metabolism and explain how its functions as a stress hormone can improve healthspan. Next, we will examine both the induction of FGF21 expression via the integrated stress response and the molecular mechanism through which FGF21 enhances healthy aging. Finally, we postulate that FGF21 resistance, similarly to insulin resistance, jeopardizes human healthspan and accelerates the aging process. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Suppression of Glut1 and Glucose Metabolism by Decreased Akt/mTORC1 Signaling Drives T Cell Impairment in B Cell Leukemia

    NARCIS (Netherlands)

    Siska, Peter J.; van der Windt, Gerritje J. W.; Kishton, Rigel J.; Cohen, Sivan; Eisner, William; MacIver, Nancie J.; Kater, Arnon P.; Weinberg, J. Brice; Rathmell, Jeffrey C.

    2016-01-01

    Leukemia can promote T cell dysfunction and exhaustion that contributes to increased susceptibility to infection and mortality. The treatment-independent mechanisms that mediate leukemia-associated T cell impairments are poorly understood, but metabolism tightly regulates T cell function and may

  7. Metabolic Modulators in Heart Disease: Past, Present, and Future.

    Science.gov (United States)

    Lopaschuk, Gary D

    2017-07-01

    Ischemic heart disease and heart failure are leading causes of mortality and morbidity worldwide. They continue to be major burden on health care systems throughout the world, despite major advances made over the past 40 years in developing new therapeutic approaches to treat these debilitating diseases. A potential therapeutic approach that has been underutilized in treating ischemic heart disease and heart failure is "metabolic modulation." Major alterations in myocardial energy substrate metabolism occur in ischemic heart disease and heart failure, and are associated with an energy deficit in the heart. A metabolic shift from mitochondrial oxidative metabolism to glycolysis, as well as an uncoupling between glycolysis and glucose oxidation, plays a crucial role in the development of cardiac inefficiency (oxygen consumed per work performed) and functional impairment in ischemic heart disease as well as in heart failure. This has led to the concept that optimizing energy substrate use with metabolic modulators can be a potentially promising approach to decrease the severity of ischemic heart disease and heart failure, primarily by improving cardiac efficiency. Two approaches for metabolic modulator therapy are to stimulate myocardial glucose oxidation and/or inhibit fatty acid oxidation. In this review, the past, present, and future of metabolic modulators as an approach to optimizing myocardial energy substrate metabolism and treating ischemic heart disease and heart failure are discussed. This includes a discussion of pharmacological interventions that target enzymes involved in fatty acid uptake, fatty acid oxidation, and glucose oxidation in the heart, as well as enzymes involved in ketone and branched chain amino acid catabolism in the heart. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  8. Metabolic syndrome impairs notch signaling and promotes apoptosis in chronically ischemic myocardium.

    Science.gov (United States)

    Elmadhun, Nassrene Y; Sabe, Ashraf A; Lassaletta, Antonio D; Chu, Louis M; Kondra, Katelyn; Sturek, Michael; Sellke, Frank W

    2014-09-01

    Impaired angiogenesis is a known consequence of metabolic syndrome (MetS); however, the mechanism is not fully understood. Recent studies have shown that the notch signaling pathway is an integral component of cardiac angiogenesis. We tested, in a clinically relevant swine model, the effects of MetS on notch and apoptosis signaling in chronically ischemic myocardium. Ossabaw swine were fed either a regular diet (control [CTL], n = 8) or a high-cholesterol diet (MetS, n = 8) to induce MetS. An ameroid constrictor was placed to induce chronic myocardial ischemia. Eleven weeks later, the wine underwent cardiac harvest of the ischemic myocardium. Downregulation of pro-angiogenesis proteins notch2, notch4, jagged2, angiopoietin 1, and endothelial nitric oxide synthase were found in the MetS group compared with the CTL group. Also, upregulation of pro-apoptosis protein caspase 8 and downregulation of anti-angiogenesis protein phosphorylated forkhead box transcription factor 03 and pro-survival proteins phosphorylated P38 and heat shock protein 90 were present in the MetS group. Cell death was increased in the MetS group compared with the CTL group. Both CTL and MetS groups had a similar arteriolar count and capillary density, and notch3 and jagged1 were both similarly concentrated in the smooth muscle wall. MetS in chronic myocardial ischemia significantly impairs notch signaling by downregulating notch receptors, ligands, and pro-angiogenesis proteins. MetS also increases apoptosis signaling, decreases survival signaling, and increases cell death in chronically ischemic myocardium. Although short-term angiogenesis appears unaffected in this model of early MetS, the molecular signals for angiogenesis are impaired, suggesting that inhibition of notch signaling might underlie the decreased angiogenesis in later stages of MetS. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  9. Investigation of the Relationship Between Molluscum Pendulum and Impairment of Carbohydrate Metabolism

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    Murat Kemal

    2011-12-01

    Full Text Available Background and Design: High blood sugar level, insulin resistance and dyslipidemia are accepted to be indicators of impaired carbohydrate metabolism. The potential role of these markers as well as the serum levels of insulin growth factor (IGF-1 and insulin growth factor binding protein (IGFBP-3 in the pathogenesis of molluscum pendulum were investigated in this study. Materials and methods: Forty-five molluscum pendulum patients and 45 age-, sex- and body mass index-matched healthy individuals as controls were enrolled in the study. Evaluation included dermatological examination, measurement of insulin resistance using HOMA-IR method, lipid profile, fasting blood glucose, postprandial blood glucose, fasting insulin, postprandial insulin, serum IGF-1 and IGFBP-3 levels. Results: Postprandial blood glucose, fasting insulin, postprandial insulin and Homeostazis Model Assesment (HOMA-IR levels of molluscum pendulum patients were statistically higher than those of controls (p=0.037, p=0.027, p=0.03, p=0.021 respectively, whereas serum IGF-1 and IGFBP-3 levels were significantly lower than those of controls (p=0.008, p=0.001. There was no difference in fasting glucose and lipid profile between the two groups. Three patients (6.7% had DM and one patient (13.3% had impaired glucose tolerance. Only one participant from the control group (2,2% had impaired glucose tolerance. The number of molluscum pendulum lesions correlated with fasting glucose, postprandial glucose, fasting insulin, postprandial insulin, HOMA-IR, total cholesterol and triglyceride levels. Conclusion: Molluscum pendulum patients should have blood glucose and insulin resistance measurements done and be followed up for DM. Patients with multiple lesions need to be evaluated for lipid problems. We suggest that serum IGF-1 and IGFBP-3 levels have no role in the pathogenesis of molluscum pendulum. (Turk­derm 2011; 45: 188-92

  10. Peroxisome Proliferators-Activated Receptor (PPAR Modulators and Metabolic Disorders

    Directory of Open Access Journals (Sweden)

    Min-Chul Cho

    2008-01-01

    Full Text Available Overweight and obesity lead to an increased risk for metabolic disorders such as impaired glucose regulation/insulin resistance, dyslipidemia, and hypertension. Several molecular drug targets with potential to prevent or treat metabolic disorders have been revealed. Interestingly, the activation of peroxisome proliferator-activated receptor (PPAR, which belongs to the nuclear receptor superfamily, has many beneficial clinical effects. PPAR directly modulates gene expression by binding to a specific ligand. All PPAR subtypes (α,γ, and σ are involved in glucose metabolism, lipid metabolism, and energy balance. PPAR agonists play an important role in therapeutic aspects of metabolic disorders. However, undesired effects of the existing PPAR agonists have been reported. A great deal of recent research has focused on the discovery of new PPAR modulators with more beneficial effects and more safety without producing undesired side effects. Herein, we briefly review the roles of PPAR in metabolic disorders, the effects of PPAR modulators in metabolic disorders, and the technologies with which to discover new PPAR modulators.

  11. Developmental Programming in Response to Intrauterine Growth Restriction Impairs Myoblast Function and Skeletal Muscle Metabolism

    Science.gov (United States)

    Yates, D. T.; Macko, A. R.; Nearing, M.; Chen, X.; Rhoads, R. P.; Limesand, S. W.

    2012-01-01

    Fetal adaptations to placental insufficiency alter postnatal metabolic homeostasis in skeletal muscle by reducing glucose oxidation rates, impairing insulin action, and lowering the proportion of oxidative fibers. In animal models of intrauterine growth restriction (IUGR), skeletal muscle fibers have less myonuclei at birth. This means that myoblasts, the sole source for myonuclei accumulation in fibers, are compromised. Fetal hypoglycemia and hypoxemia are complications that result from placental insufficiency. Hypoxemia elevates circulating catecholamines, and chronic hypercatecholaminemia has been shown to reduce fetal muscle development and growth. We have found evidence for adaptations in adrenergic receptor expression profiles in myoblasts and skeletal muscle of IUGR sheep fetuses with placental insufficiency. The relationship of β-adrenergic receptors shifts in IUGR fetuses because Adrβ2 expression levels decline and Adrβ1 expression levels are unaffected in myofibers and increased in myoblasts. This adaptive response would suppress insulin signaling, myoblast incorporation, fiber hypertrophy, and glucose oxidation. Furthermore, this β-adrenergic receptor expression profile persists for at least the first month in IUGR lambs and lowers their fatty acid mobilization. Developmental programming of skeletal muscle adrenergic receptors partially explains metabolic and endocrine differences in IUGR offspring, and the impact on metabolism may result in differential nutrient utilization. PMID:22900186

  12. Developmental Programming in Response to Intrauterine Growth Restriction Impairs Myoblast Function and Skeletal Muscle Metabolism

    Directory of Open Access Journals (Sweden)

    D. T. Yates

    2012-01-01

    Full Text Available Fetal adaptations to placental insufficiency alter postnatal metabolic homeostasis in skeletal muscle by reducing glucose oxidation rates, impairing insulin action, and lowering the proportion of oxidative fibers. In animal models of intrauterine growth restriction (IUGR, skeletal muscle fibers have less myonuclei at birth. This means that myoblasts, the sole source for myonuclei accumulation in fibers, are compromised. Fetal hypoglycemia and hypoxemia are complications that result from placental insufficiency. Hypoxemia elevates circulating catecholamines, and chronic hypercatecholaminemia has been shown to reduce fetal muscle development and growth. We have found evidence for adaptations in adrenergic receptor expression profiles in myoblasts and skeletal muscle of IUGR sheep fetuses with placental insufficiency. The relationship of β-adrenergic receptors shifts in IUGR fetuses because Adrβ2 expression levels decline and Adrβ1 expression levels are unaffected in myofibers and increased in myoblasts. This adaptive response would suppress insulin signaling, myoblast incorporation, fiber hypertrophy, and glucose oxidation. Furthermore, this β-adrenergic receptor expression profile persists for at least the first month in IUGR lambs and lowers their fatty acid mobilization. Developmental programming of skeletal muscle adrenergic receptors partially explains metabolic and endocrine differences in IUGR offspring, and the impact on metabolism may result in differential nutrient utilization.

  13. Glibenclamide Mimics Metabolic Effects of Metformin in H9c2 Cells.

    Science.gov (United States)

    Salani, Barbara; Ravera, Silvia; Fabbi, Patrizia; Garibaldi, Silvano; Passalacqua, Mario; Brunelli, Claudio; Maggi, Davide; Cordera, Renzo; Ameri, Pietro

    2017-01-01

    Sulfonylureas, such as glibenclamide, are antidiabetic drugs that stimulate beta-cell insulin secretion by binding to the sulfonylureas receptors (SURs) of adenosine triphosphate-sensitive potassium channels (KATP). Glibenclamide may be also cardiotoxic, this effect being ascribed to interference with the protective function of cardiac KATP channels for which glibenclamide has high affinity. Prompted by recent evidence that glibenclamide impairs energy metabolism of renal cells, we investigated whether this drug also affects the metabolism of cardiac cells. The cardiomyoblast cell line H9c2 was treated for 24 h with glibenclamide or metformin, a known inhibitor of the mitochondrial respiratory chain. Cell viability was evaluated by sulforodhamine B assay. ATP and AMP were measured according to the enzyme coupling method and oxygen consumption by using an amperometric electrode, while Fo-F1 ATP synthase activity assay was evaluated by chemiluminescent method. Protein expression was measured by western blot. Glibenclamide deregulated energy balance of H9c2 cardiomyoblasts in a way similar to that of metformin. It inhibited mitochondrial complexes I, II and III with ensuing impairment of oxygen consumption and ATP synthase activity, ATP depletion and increased AMPK phosphorylation. Furthermore, glibenclamide disrupted mitochondrial subcellular organization. The perturbation of mitochondrial energy balance was associated with enhanced anaerobic glycolysis, with increased activity of phosphofructo kinase, pyruvate kinase and lactic dehydrogenase. Interestingly, some additive effects of glibenclamide and metformin were observed. Glibenclamide deeply alters cell metabolism in cardiac cells by impairing mitochondrial organization and function. This may further explain the risk of cardiovascular events associated with the use of this drug, alone or in combination with metformin. © 2017 The Author(s). Published by S. Karger AG, Basel.

  14. 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.

  15. 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.)

  16. 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

  17. 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.

  18. Muscle insulin sensitivity and glucose metabolism are controlled by the intrinsic muscle clock

    DEFF Research Database (Denmark)

    Dyar, Kenneth A.; Ciciliot, Stefano; Wright, Lauren E.

    2014-01-01

    Circadian rhythms control metabolism and energy homeostasis, but the role of the skeletal muscle clock has never been explored. We generated conditional and inducible mouse lines with muscle-specific ablation of the core clock gene Bmal1. Skeletal muscles from these mice showed impaired insulin-s...

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Impaired hippocampal glucose metabolism during and after flurothyl-induced seizures in mice: Reduced phosphorylation coincides with reduced activity of pyruvate dehydrogenase.

    Science.gov (United States)

    McDonald, Tanya S; Borges, Karin

    2017-07-01

    To determine changes in glucose metabolism and the enzymes involved in the hippocampus ictally and postictally in the acute mouse flurothyl seizure model. [U- 13 C]-Glucose was injected (i.p.) prior to, or following a 5 min flurothyl-induced seizure. Fifteen minutes later, mice were killed and the total metabolite levels and % 13 C enrichment were analyzed in the hippocampal formation using gas chromatography-mass spectrometry. Activities of key metabolic and antioxidant enzymes and the phosphorylation status of pyruvate dehydrogenase were measured, along with lipid peroxidation. During seizures, total lactate levels increased 1.7-fold; however, [M + 3] enrichment of both lactate and alanine were reduced by 30% and 43%, respectively, along with a 28% decrease in phosphofructokinase activity. Postictally the % 13 C enrichments of all measured tricarboxylic acid (TCA) cycle intermediates and the amino acids were reduced by 46-93%. At this time, pyruvate dehydrogenase (PDH) activity was 56% of that measured in controls, and there was a 1.9-fold increase in the phosphorylation of PDH at ser232. Phosphorylation of PDH is known to decrease its activity. Here, we show that the increase of lactate levels during flurothyl seizures is from a source other than [U- 13 C]-glucose, such as glycogen. Surprisingly, although we saw a reduction in phosphofructokinase activity during the seizure, metabolism of [U- 13 C]-glucose into the TCA cycle seemed unaffected. Similar to our recent findings in the chronic phase of the pilocarpine model, postictally the metabolism of glucose by glycolysis and the TCA cycle was impaired along with reduced PDH activity. Although this decrease in activity may be a protective mechanism to reduce oxidative stress, which is observed in the flurothyl model, ATP is critical to the recovery of ion and neurotransmitter balance and return to normal brain function. Thus we identified promising novel strategies to enhance energy metabolism and recovery from

  2. Metabolic Myopathies.

    Science.gov (United States)

    Tarnopolsky, Mark A

    2016-12-01

    Metabolic myopathies are genetic disorders that impair intermediary metabolism in skeletal muscle. Impairments in glycolysis/glycogenolysis (glycogen-storage disease), fatty acid transport and oxidation (fatty acid oxidation defects), and the mitochondrial respiratory chain (mitochondrial myopathies) represent the majority of known defects. The purpose of this review is to develop a diagnostic and treatment algorithm for the metabolic myopathies. The metabolic myopathies can present in the neonatal and infant period as part of more systemic involvement with hypotonia, hypoglycemia, and encephalopathy; however, most cases present in childhood or in adulthood with exercise intolerance (often with rhabdomyolysis) and weakness. The glycogen-storage diseases present during brief bouts of high-intensity exercise, whereas fatty acid oxidation defects and mitochondrial myopathies present during a long-duration/low-intensity endurance-type activity or during fasting or another metabolically stressful event (eg, surgery, fever). The clinical examination is often normal between acute events, and evaluation involves exercise testing, blood testing (creatine kinase, acylcarnitine profile, lactate, amino acids), urine organic acids (ketones, dicarboxylic acids, 3-methylglutaconic acid), muscle biopsy (histology, ultrastructure, enzyme testing), MRI/spectroscopy, and targeted or untargeted genetic testing. Accurate and early identification of metabolic myopathies can lead to therapeutic interventions with lifestyle and nutritional modification, cofactor treatment, and rapid treatment of rhabdomyolysis.

  3. Manifestations of Renal Impairment in Fructose-induced Metabolic Syndrome.

    Science.gov (United States)

    Bratoeva, Kameliya; Stoyanov, George S; Merdzhanova, Albena; Radanova, Mariya

    2017-11-07

    Introduction International studies show an increased incidence of chronic kidney disease (CKD) in patients with metabolic syndrome (MS). It is assumed that the major components of MS - obesity, insulin resistance, dyslipidemia, and hypertension - are linked to renal damage through the systemic release of several pro-inflammatory mediators, such as uric acid (UA), C-reactive protein (CRP), and generalized oxidative stress. The aim of the present study was to investigate the extent of kidney impairment and manifestations of dysfunction in rats with fructose-induced MS. Methods We used a model of high-fructose diet in male Wistar rats with 35% glucose-fructose corn syrup in drinking water over a duration of 16 weeks. The experimental animals were divided into two groups: control and high-fructose drinking (HFD). Serum samples were obtained from both groups for laboratory study, and the kidneys were extracted for observation via light microscopy examination. Results All HFD rats developed obesity, hyperglycemia, hypertriglyceridemia, increased levels of CRP and UA (when compared to the control group), and oxidative stress with high levels of malondialdehyde and low levels of reduced glutathione. The kidneys of the HFD group revealed a significant increase in kidney weight in the absence of evidence of renal dysfunction and electrolyte disturbances. Under light microscopy, the kidneys of the HFD group revealed amyloid deposits in Kimmelstiel-Wilson-like nodules and the walls of the large caliber blood vessels, early-stage atherosclerosis with visible ruptures and scarring, hydropic change (vacuolar degeneration) in the epithelial cells covering the proximal tubules, and increased eosinophilia in the distant tubules when compared to the control group. Conclusion Under the conditions of a fructose-induced metabolic syndrome, high serum UA and CRP correlate to the development of early renal disorders without a clinical manifestation of renal dysfunction. These

  4. Impaired Hippocampal Glutamate and Glutamine Metabolism in the db/db Mouse Model of Type 2 Diabetes Mellitus

    DEFF Research Database (Denmark)

    Andersen, Jens Velde; Nissen, Jakob Dahl; Christensen, Sofie Kjellerup

    2017-01-01

    Type 2 diabetes mellitus (T2DM) is a risk factor for the development of Alzheimer's disease, and changes in brain energy metabolism have been suggested as a causative mechanism. The aim of this study was to investigate the cerebral metabolism of the important amino acids glutamate and glutamine...... significantly reduced 13C labeling in glutamate, glutamine, GABA, citrate, and aspartate from metabolism of [U-13C]glutamate. Additionally, reduced 13C labeling were observed in GABA, citrate, and aspartate from [U-13C]glutamine metabolism in hippocampal slices of db/db mice when compared to controls. None...

  5. Streptococcus agalactiae impairs cerebral bioenergetics in experimentally infected silver catfish.

    Science.gov (United States)

    Baldissera, Matheus D; Souza, Carine F; Parmeggiani, Belisa S; Santos, Roberto C V; Leipnitz, Guilhian; Moreira, Karen L S; da Rocha, Maria Izabel U M; da Veiga, Marcelo L; Baldisserotto, Bernardo

    2017-10-01

    It is becoming evident that bacterial infectious diseases affect brain energy metabolism, where alterations of enzymatic complexes of the mitochondrial respiratory chain and creatine kinase (CK) lead to an impairment of cerebral bioenergetics which contribute to disease pathogenesis in the central nervous system (CNS). Based on this evidence, the aim of this study was to evaluate whether alterations in the activity of complex IV of the respiratory chain and CK contribute to impairment of cerebral bioenergetics during Streptococcus agalactiae infection in silver catfish (Rhamdia quelen). The activity of complex IV of the respiratory chain in brain increased, while the CK activity decreased in infected animals compared to uninfected animals. Brain histopathology revealed inflammatory demyelination, gliosis of the brain and intercellular edema in infected animals. Based on this evidence, S. agalactiae infection causes an impairment in cerebral bioenergetics through the augmentation of complex IV activity, which may be considered an adaptive response to maintain proper functioning of the electron respiratory chain, as well as to ensure ongoing electron flow through the electron transport chain. Moreover, inhibition of cerebral CK activity contributes to lower availability of ATP, contributing to impairment of cerebral energy homeostasis. In summary, these alterations contribute to disease pathogenesis linked to the CNS. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. 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.

  7. Abnormal brain iron metabolism in Irp2 deficient mice is associated with mild neurological and behavioral impairments.

    Directory of Open Access Journals (Sweden)

    Kimberly B Zumbrennen-Bullough

    Full Text Available Iron Regulatory Protein 2 (Irp2, Ireb2 is a central regulator of cellular iron homeostasis in vertebrates. Two global knockout mouse models have been generated to explore the role of Irp2 in regulating iron metabolism. While both mouse models show that loss of Irp2 results in microcytic anemia and altered body iron distribution, discrepant results have drawn into question the role of Irp2 in regulating brain iron metabolism. One model shows that aged Irp2 deficient mice develop adult-onset progressive neurodegeneration that is associated with axonal degeneration and loss of Purkinje cells in the central nervous system. These mice show iron deposition in white matter tracts and oligodendrocyte soma throughout the brain. A contrasting model of global Irp2 deficiency shows no overt or pathological signs of neurodegeneration or brain iron accumulation, and display only mild motor coordination and balance deficits when challenged by specific tests. Explanations for conflicting findings in the severity of the clinical phenotype, brain iron accumulation and neuronal degeneration remain unclear. Here, we describe an additional mouse model of global Irp2 deficiency. Our aged Irp2-/- mice show marked iron deposition in white matter and in oligodendrocytes while iron content is significantly reduced in neurons. Ferritin and transferrin receptor 1 (TfR1, Tfrc, expression are increased and decreased, respectively, in the brain from Irp2-/- mice. These mice show impairments in locomotion, exploration, motor coordination/balance and nociception when assessed by neurological and behavioral tests, but lack overt signs of neurodegenerative disease. Ultrastructural studies of specific brain regions show no evidence of neurodegeneration. Our data suggest that Irp2 deficiency dysregulates brain iron metabolism causing cellular dysfunction that ultimately leads to mild neurological, behavioral and nociceptive impairments.

  8. Mitochondrial Dysfunction, Through Impaired Autophagy, Leads to Endoplasmic Reticulum Stress, Deregulated Lipid Metabolism, and Pancreatitis in Animal Models.

    Science.gov (United States)

    Biczo, Gyorgy; Vegh, Eszter T; Shalbueva, Natalia; Mareninova, Olga A; Elperin, Jason; Lotshaw, Ethan; Gretler, Sophie; Lugea, Aurelia; Malla, Sudarshan R; Dawson, David; Ruchala, Piotr; Whitelegge, Julian; French, Samuel W; Wen, Li; Husain, Sohail Z; Gorelick, Fred S; Hegyi, Peter; Rakonczay, Zoltan; Gukovsky, Ilya; Gukovskaya, Anna S

    2018-02-01

    Little is known about the signaling pathways that initiate and promote acute pancreatitis (AP). The pathogenesis of AP has been associated with abnormal increases in cytosolic Ca 2+ , mitochondrial dysfunction, impaired autophagy, and endoplasmic reticulum (ER) stress. We analyzed the mechanisms of these dysfunctions and their relationships, and how these contribute to development of AP in mice and rats. Pancreatitis was induced in C57BL/6J mice (control) and mice deficient in peptidylprolyl isomerase D (cyclophilin D, encoded by Ppid) by administration of L-arginine (also in rats), caerulein, bile acid, or an AP-inducing diet. Parameters of pancreatitis, mitochondrial function, autophagy, ER stress, and lipid metabolism were measured in pancreatic tissue, acinar cells, and isolated mitochondria. Some mice with AP were given trehalose to enhance autophagic efficiency. Human pancreatitis tissues were analyzed by immunofluorescence. Mitochondrial dysfunction in pancreas of mice with AP was induced by either mitochondrial Ca 2+ overload or through a Ca 2+ overload-independent pathway that involved reduced activity of ATP synthase (80% inhibition in pancreatic mitochondria isolated from rats or mice given L-arginine). Both pathways were mediated by cyclophilin D and led to mitochondrial depolarization and fragmentation. Mitochondrial dysfunction caused pancreatic ER stress, impaired autophagy, and deregulation of lipid metabolism. These pathologic responses were abrogated in cyclophilin D-knockout mice. Administration of trehalose largely prevented trypsinogen activation, necrosis, and other parameters of pancreatic injury in mice with L-arginine AP. Tissues from patients with pancreatitis had markers of mitochondrial damage and impaired autophagy, compared with normal pancreas. In different animal models, we find a central role for mitochondrial dysfunction, and for impaired autophagy as its principal downstream effector, in development of AP. In particular, the

  9. 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

  10. Moderately Low Magnesium Intake Impairs Growth of Lean Body Mass in Obese-Prone and Obese-Resistant Rats Fed a High-Energy Diet

    Directory of Open Access Journals (Sweden)

    Jesse Bertinato

    2016-04-01

    Full Text Available The physical and biochemical changes resulting from moderately low magnesium (Mg intake are not fully understood. Obesity and associated co-morbidities affect Mg metabolism and may exacerbate Mg deficiency and physiological effects. Male rats selectively bred for diet-induced obesity (OP, obese-prone or resistance (OR, obese-resistant were fed a high-fat, high-energy diet containing moderately low (LMg, 0.116 ± 0.001 g/kg or normal (NMg, 0.516 ± 0.007 g/kg Mg for 13 weeks. The growth, body composition, mineral homeostasis, bone development, and glucose metabolism of the rats were examined. OP and OR rats showed differences (p < 0.05 in many physical and biochemical measures regardless of diet. OP and OR rats fed the LMg diet had decreased body weight, lean body mass, decreased femoral size (width, weight, and volume, and serum Mg and potassium concentrations compared to rats fed the NMg diet. The LMg diet increased serum calcium (Ca concentration in both rat strains with a concomitant decrease in serum parathyroid hormone concentration only in the OR strain. In the femur, Mg concentration was reduced, whereas concentrations of Ca and sodium were increased in both strains fed the LMg diet. Plasma glucose and insulin concentrations in an oral glucose tolerance test were similar in rats fed the LMg or NMg diets. These results show that a moderately low Mg diet impairs the growth of lean body mass and alters femoral geometry and mineral metabolism in OP and OR rats fed a high-energy diet.

  11. 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

  12. Ptp1b deletion in pro-opiomelanocortin neurons increases energy expenditure and impairs endothelial function via TNF-α dependent mechanisms.

    Science.gov (United States)

    Bruder-Nascimento, Thiago; Kennard, Simone; Antonova, Galina; Mintz, James D; Bence, Kendra K; Belin de Chantemèle, Eric J

    2016-06-01

    Protein tyrosine phosphatase 1b (Ptp1b) is a negative regulator of leptin and insulin-signalling pathways. Its targeted deletion in proopiomelanocortin (POMC) neurons protects mice from obesity and diabetes by increasing energy expenditure. Inflammation accompanies increased energy expenditure. Therefore, the present study aimed to determine whether POMC-Ptp1b deletion increases energy expenditure via an inflammatory process, which would impair endothelial function. We characterized the metabolic and cardiovascular phenotypes of Ptp1b+/+ and POMC-Ptp1b-/- mice. Clamp studies revealed that POMC-Ptp1b deletion reduced body fat and increased energy expenditure as evidenced by a decrease in feed efficiency and an increase in oxygen consumption and respiratory exchange ratio. POMC-Ptp1b deletion induced a 2.5-fold increase in plasma tumour necrosis factor α (TNF-α) levels and elevated body temperature. Vascular studies revealed an endothelial dysfunction in POMC-Ptp1b-/- mice. Nitric oxide synthase inhibition [N-nitro-L-arginine methyl ester (L-NAME)] reduced relaxation to a similar extent in Ptp1b+/+ and POMC-Ptp1b-/- mice. POMC-Ptp1b deletion decreased ROS-scavenging enzymes [superoxide dismutases (SODs)] whereas it increased ROS-generating enzymes [NADPH oxidases (NOXs)] and cyclooxygenase-2 (COX-1) expression, in aorta. ROS scavenging or NADPH oxidase inhibition only partially improved relaxation whereas COX-2 inhibition and thromboxane-A2 (TXA2) antagonism fully restored relaxation in POMC-Ptp1b-/- mice Chronic treatment with the soluble TNF-α receptor etanercept decreased body temperature, restored endothelial function and reestablished aortic COX-2, NOXs and SOD expression to their baseline levels in POMC-Ptp1b-/- mice. However, etanercept promoted body weight gain and decreased energy expenditure in POMC-Ptp1b-/- mice. POMC-Ptp1b deletion increases plasma TNF-α levels, which contribute to body weight regulation via increased energy expenditure and impair

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

    Directory of Open Access Journals (Sweden)

    Siôn A. Parry

    2017-07-01

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

  14. Exposures to arsenite and methylarsonite produce insulin resistance and impair insulin-dependent glycogen metabolism in hepatocytes.

    Science.gov (United States)

    Zhang, Chongben; Fennel, Emily M J; Douillet, Christelle; Stýblo, Miroslav

    2017-12-01

    Environmental exposure to inorganic arsenic (iAs) has been shown to disturb glucose homeostasis, leading to diabetes. Previous laboratory studies have suggested several mechanisms that may underlie the diabetogenic effects of iAs exposure, including (i) inhibition of insulin signaling (leading to insulin resistance) in glucose metabolizing peripheral tissues, (ii) inhibition of insulin secretion by pancreatic β cells, and (iii) dysregulation of the methylation or expression of genes involved in maintenance of glucose or insulin metabolism and function. Published studies have also shown that acute or chronic iAs exposures may result in depletion of hepatic glycogen stores. However, effects of iAs on pathways and mechanisms that regulate glycogen metabolism in the liver have never been studied. The present study examined glycogen metabolism in primary murine hepatocytes exposed in vitro to arsenite (iAs 3+ ) or its methylated metabolite, methylarsonite (MAs 3+ ). The results show that 4-h exposures to iAs 3+ and MAs 3+ at concentrations as low as 0.5 and 0.2 µM, respectively, decreased glycogen content in insulin-stimulated hepatocytes by inhibiting insulin-dependent activation of glycogen synthase (GS) and by inducing activity of glycogen phosphorylase (GP). Further investigation revealed that both iAs 3+ and MAs 3+ inhibit insulin-dependent phosphorylation of protein kinase B/Akt, one of the mechanisms involved in the regulation of GS and GP by insulin. Thus, inhibition of insulin signaling (i.e., insulin resistance) is likely responsible for the dysregulation of glycogen metabolism in hepatocytes exposed to iAs 3+ and MAs 3+ . This study provides novel information about the mechanisms by which iAs exposure impairs glucose homeostasis, pointing to hepatic metabolism of glycogen as one of the targets.

  15. 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

  16. 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.

  17. Dietary Intakes and Nutritional Issues in Neurologically Impaired Children

    Directory of Open Access Journals (Sweden)

    Francesca Penagini

    2015-11-01

    Full Text Available Neurologically impaired (NI children are at increased risk of malnutrition due to several nutritional and non-nutritional factors. Among the nutritional factors, insufficient dietary intake as a consequence of feeding difficulties is one of the main issues. Feeding problems are frequently secondary to oropharyngeal dysphagia, which usually correlates with the severity of motor impairment and presents in around 90% of preschool children with cerebral palsy (CP during the first year of life. Other nutritional factors are represented by excessive nutrient losses, often subsequent to gastroesophageal reflux and altered energy metabolism. Among the non-nutritional factors, the type and severity of neurological impairment, ambulatory status, the degree of cognitive impairment, and use of entiepileptic medication altogether concur to determination of nutritional status. With the present review, the current literature is discussed and a practical approach for nutritional assessment in NI children is proposed. Early identification and intervention of nutritional issues of NI children with a multidisciplinary approach is crucial to improve the overall health and quality of life of these complex children.

  18. Dietary Intakes and Nutritional Issues in Neurologically Impaired Children.

    Science.gov (United States)

    Penagini, Francesca; Mameli, Chiara; Fabiano, Valentina; Brunetti, Domenica; Dilillo, Dario; Zuccotti, Gian Vincenzo

    2015-11-13

    Neurologically impaired (NI) children are at increased risk of malnutrition due to several nutritional and non-nutritional factors. Among the nutritional factors, insufficient dietary intake as a consequence of feeding difficulties is one of the main issues. Feeding problems are frequently secondary to oropharyngeal dysphagia, which usually correlates with the severity of motor impairment and presents in around 90% of preschool children with cerebral palsy (CP) during the first year of life. Other nutritional factors are represented by excessive nutrient losses, often subsequent to gastroesophageal reflux and altered energy metabolism. Among the non-nutritional factors, the type and severity of neurological impairment, ambulatory status, the degree of cognitive impairment, and use of entiepileptic medication altogether concur to determination of nutritional status. With the present review, the current literature is discussed and a practical approach for nutritional assessment in NI children is proposed. Early identification and intervention of nutritional issues of NI children with a multidisciplinary approach is crucial to improve the overall health and quality of life of these complex children.

  19. 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.

  20. 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.

  1. A diagnostic algorithm for metabolic myopathies.

    Science.gov (United States)

    Berardo, Andres; DiMauro, Salvatore; Hirano, Michio

    2010-03-01

    Metabolic myopathies comprise a clinically and etiologically diverse group of disorders caused by defects in cellular energy metabolism, including the breakdown of carbohydrates and fatty acids to generate adenosine triphosphate, predominantly through mitochondrial oxidative phosphorylation. Accordingly, the three main categories of metabolic myopathies are glycogen storage diseases, fatty acid oxidation defects, and mitochondrial disorders due to respiratory chain impairment. The wide clinical spectrum of metabolic myopathies ranges from severe infantile-onset multisystemic diseases to adult-onset isolated myopathies with exertional cramps. Diagnosing these diverse disorders often is challenging because clinical features such as recurrent myoglobinuria and exercise intolerance are common to all three types of metabolic myopathy. Nevertheless, distinct clinical manifestations are important to recognize as they can guide diagnostic testing and lead to the correct diagnosis. This article briefly reviews general clinical aspects of metabolic myopathies and highlights approaches to diagnosing the relatively more frequent subtypes (Fig. 1). Fig. 1 Clinical algorithm for patients with exercise intolerance in whom a metabolic myopathy is suspected. CK-creatine kinase; COX-cytochrome c oxidase; CPT-carnitine palmitoyl transferase; cyt b-cytochrome b; mtDNA-mitochondrial DNA; nDNA-nuclear DNA; PFK-phosphofructokinase; PGAM-phosphoglycerate mutase; PGK-phosphoglycerate kinase; PPL-myophosphorylase; RRF-ragged red fibers; TFP-trifunctional protein deficiency; VLCAD-very long-chain acyl-coenzyme A dehydrogenase.

  2. Tributyltin chloride leads to adiposity and impairs metabolic functions in the rat liver and pancreas.

    Science.gov (United States)

    Bertuloso, Bruno D; Podratz, Priscila L; Merlo, Eduardo; de Araújo, Julia F P; Lima, Leandro C F; de Miguel, Emilio C; de Souza, Leticia N; Gava, Agata L; de Oliveira, Miriane; Miranda-Alves, Leandro; Carneiro, Maria T W D; Nogueira, Celia R; Graceli, Jones B

    2015-05-19

    Tributyltin chloride (TBT) is an environmental contaminant used in antifouling paints of boats. Endocrine disruptor effects of TBT are well established in animal models. However, the adverse effects on metabolism are less well understood. The toxicity of TBT in the white adipose tissue (WAT), liver and pancreas of female rats were assessed. Animals were divided into control and TBT (0.1 μg/kg/day) groups. TBT induced an increase in the body weight of the rats by the 15th day of oral exposure. The weight gain was associated with high parametrial (PR) and retroperitoneal (RP) WAT weights. TBT-treatment increased the adiposity, inflammation and expression of ERα and PPARγ proteins in both RP and PR WAT. In 3T3-L1 cells, estrogen treatment reduced lipid droplets accumulation, however increased the ERα protein expression. In contrast, TBT-treatment increased the lipid accumulation and reduced the ERα expression. WAT metabolic changes led to hepatic inflammation, lipid accumulation, increase of PPARγ and reduction of ERα protein expression. Accordingly, there were increases in the glucose tolerance and insulin sensitivity tests with increases in the number of pancreatic islets and insulin levels. These findings suggest that TBT leads to adiposity in WAT specifically, impairing the metabolic functions of the liver and pancreas. Copyright © 2015. Published by Elsevier Ireland Ltd.

  3. Effects of hypogonadism on bone metabolism in female adolescents and young adults.

    Science.gov (United States)

    Misra, Madhusmita

    2012-01-24

    Gonadal steroids, including androgens and oestrogens, play a critical part in bone metabolism, and conditions associated with a deficiency of gonadal steroids can reduce BMD in adults and impair bone accrual in adolescents. In addition, other associated hormone alterations, for example, insulin-like growth factor 1 deficiency or high cortisol levels, can further exacerbate the effect of hypogonadism on bone metabolism, as can factors such as calcium and vitamin D deficiency, low body weight and exercise status. This Review discusses the effects of different hypogonadal states on bone metabolism in female adolescents and young adults, with particular emphasis on conditions associated with low energy availability, such as anorexia nervosa and athletic amenorrhoea, in which many factors other than hypogonadism affect bone. In contrast to most hypogonadal conditions, in which replacement of gonadal steroids is sufficient to normalize bone accrual rates and BMD, gonadal steroid replacement may not be sufficient to normalize bone metabolism in these states of energy deficit.

  4. 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).

  5. Abnormality of cerebral cortical glucose metabolism in temporal lobe epilepsy with cognitive function impairment

    International Nuclear Information System (INIS)

    Bang-Hung Yang; Tsung-Szu Yeh; Tung-Ping Su; Jyh-Cheng Chen; Ren-Shyan Liu

    2004-01-01

    Objective: People with epilepsy commonly report having problems with their memory. Many indicate that memory difficulties significantly hinder their functioning at work, in school, and at home. Besides, some studies have reported that memory performance as a prognostic factor is of most value in patients with risk of refractory epilepsy and when used in a multidisciplinary setting. However, the cerebral cortical areas involving memory impairment in epilepsy is still unknown. The purpose of this study was to access changes of cerebral glucose metabolism of epilepsy patients using [F-18] fluorodeoxyglucose positron emission tomography (FDG PET). Method: Nine temporal lobe epilepsy patients were studied. Each patient was confirmed with lesions in right mesial temporal lobe by MRI, PET and EEG. Serial cognition function tests were performed. Regional cerebral glucose metabolism (rCMRglc) was measured by PET at 45 minutes after injection of 370 MBq of FDG. Parametric images were generated by grand mean scaling each scan to 50. The images were then transformed into standard stereotactic space. Statistical parametric mapping (SPM2) was applied to find the correlations between verbal memory, figure memory, perception intelligent quotation (PIQ) and rCMRglc in epilepsy patients. The changes of rCMRglc were significant if corrected p value was less than 0.05. Results: There was no significant relationship between figure memory score and verbal memory score. FDG-PET scan showed changes of rCMRglc positive related with verbal memory score in precentral gyms of right frontal lobe (Brodmann area 4, corrected p < 0.001, voxel size 240) and cingulated gyms of right limbic lobe (Brodmann area 32, corrected p=0.002, voxel size 143). No negative relationship was demonstrable between verbal memory and rCMRglc in this study. Besides, significanfiy positive correlation between figure memory was shown in cuneus of right occipital lobe (Brodmann area 18, corrected p < 0.001, voxel size

  6. 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.

  7. Vascular cognitive impairment, dementia, aging and energy demand. A vicious cycle.

    Science.gov (United States)

    Popa-Wagner, A; Buga, Ana-Maria; Popescu, B; Muresanu, D

    2015-08-01

    To a great extent, cognitive health depends on cerebrovascular health and a deeper understanding of the subtle interactions between cerebrovascular function and cognition is needed to protect humans from one of the most devastating affliction, dementia. However, the underlying biological mechanisms are still not completely clear. Many studies demonstrated that the neurovascular unit is compromised in cerebrovascular diseases and also in other types of dementia. The hemodynamic neurovascular coupling ensures a strong increase of the cerebral blood flow (CBF) and an acute increase in neuronal glucose uptake upon increased neural activity. Dysfunction of cerebral autoregulation with increasing age along with age-related structural and functional alterations in cerebral blood vessels including accumulation of amyloid-beta (Aβ) in the media of cortical arterioles, neurovascular uncoupling due to astrocyte endfeet retraction, impairs the CBF and increases the neuronal degeneration and susceptibility to hypoxia and ischemia. A decreased cerebral glucose metabolism is an early event in Alzheimer's disease (AD) pathology and may precede the neuropathological Aβ deposition associated with AD. Aβ accumulation in turn leads to further decreases in the CBF closing the vicious cycle. Alzheimer, aging and diabetes are also influenced by insulin/insulin-like growth factor-1 signaling, and accumulated evidence indicates sporadic AD is associated with disturbed brain insulin metabolism. Understanding how vascular and metabolic factors interfere with progressive loss of functional neuronal networks becomes essential to develop efficient drugs to prevent cognitive decline in elderly.

  8. Brain glucose metabolism during hypoglycemia in type 1 diabetes: insights from functional and metabolic neuroimaging studies.

    Science.gov (United States)

    Rooijackers, Hanne M M; Wiegers, Evita C; Tack, Cees J; van der Graaf, Marinette; de Galan, Bastiaan E

    2016-02-01

    Hypoglycemia is the most frequent complication of insulin therapy in patients with type 1 diabetes. Since the brain is reliant on circulating glucose as its main source of energy, hypoglycemia poses a threat for normal brain function. Paradoxically, although hypoglycemia commonly induces immediate decline in cognitive function, long-lasting changes in brain structure and cognitive function are uncommon in patients with type 1 diabetes. In fact, recurrent hypoglycemia initiates a process of habituation that suppresses hormonal responses to and impairs awareness of subsequent hypoglycemia, which has been attributed to adaptations in the brain. These observations sparked great scientific interest into the brain's handling of glucose during (recurrent) hypoglycemia. Various neuroimaging techniques have been employed to study brain (glucose) metabolism, including PET, fMRI, MRS and ASL. This review discusses what is currently known about cerebral metabolism during hypoglycemia, and how findings obtained by functional and metabolic neuroimaging techniques contributed to this knowledge.

  9. 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.

  10. Progressive metabolic impairment underlies the novel nematicidal action of fluensulfone on the potato cyst nematode Globodera pallida.

    Science.gov (United States)

    Kearn, James; Lilley, Catherine; Urwin, Peter; O'Connor, Vincent; Holden-Dye, Lindy

    2017-10-01

    Fluensulfone is a new nematicide with an excellent profile of selective toxicity against plant parasitic nematodes. Here, its effects on the physiology and biochemistry of the potato cyst nematode Globodera pallida have been investigated and comparisons made with its effect on the life-span of the free-living nematode Caenorhabditis elegans to provide insight into its mode of action and its selective toxicity. Fluensulfone exerts acute effects (≤1h; ≥100μM) on stylet thrusting and motility of hatched second stage G. pallida juveniles (J2s). Chronic exposure to lower concentrations of fluensulfone (≥3days; ≤30μM), reveals a slowly developing metabolic insult in which G. pallida J2s sequentially exhibit a reduction in motility, loss of a metabolic marker for cell viability, high lipid content and tissue degeneration prior to death. These effects are absent in adults and dauers of the model genetic nematode Caenorhabditis elegans. The nematicidal action of fluensulfone follows a time-course which progresses from an early impact on motility through to an accumulating metabolic impairment, an inability to access lipid stores and death. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Cerebral metabolism in experimental hydrocephalus: an in vivo 1H and 31P magnetic resonance spectroscopy study

    NARCIS (Netherlands)

    Braun, K. P.; van Eijsden, P.; Vandertop, W. P.; de Graaf, R. A.; Gooskens, R. H.; Tulleken, K. A.; Nicolay, K.

    1999-01-01

    Brain damage in patients with hydrocephalus is caused by mechanical forces and cerebral ischemia. The severity and localization of impaired cerebral blood flow and metabolism are still largely unknown. Magnetic resonance (MR) spectroscopy offers the opportunity to investigate cerebral energy

  12. Mitochondrial biogenesis and energy production in differentiating murine stem cells: a functional metabolic study.

    Science.gov (United States)

    Han, Sungwon; Auger, Christopher; Thomas, Sean C; Beites, Crestina L; Appanna, Vasu D

    2014-02-01

    The significance of metabolic networks in guiding the fate of the stem cell differentiation is only beginning to emerge. Oxidative metabolism has been suggested to play a major role during this process. Therefore, it is critical to understand the underlying mechanisms of metabolic alterations occurring in stem cells to manipulate the ultimate outcome of these pluripotent cells. Here, using P19 murine embryonal carcinoma cells as a model system, the role of mitochondrial biogenesis and the modulation of metabolic networks during dimethyl sulfoxide (DMSO)-induced differentiation are revealed. Blue native polyacrylamide gel electrophoresis (BN-PAGE) technology aided in profiling key enzymes, such as hexokinase (HK) [EC 2.7.1.1], glucose-6-phosphate isomerase (GPI) [EC 5.3.1.9], pyruvate kinase (PK) [EC 2.7.1.40], Complex I [EC 1.6.5.3], and Complex IV [EC 1.9.3.1], that are involved in the energy budget of the differentiated cells. Mitochondrial adenosine triphosphate (ATP) production was shown to be increased in DMSO-treated cells upon exposure to the tricarboxylic acid (TCA) cycle substrates, such as succinate and malate. The increased mitochondrial activity and biogenesis were further confirmed by immunofluorescence microscopy. Collectively, the results indicate that oxidative energy metabolism and mitochondrial biogenesis were sharply upregulated in DMSO-differentiated P19 cells. This functional metabolic and proteomic study provides further evidence that modulation of mitochondrial energy metabolism is a pivotal component of the cellular differentiation process and may dictate the final destiny of stem cells.

  13. Consumption of dairy foods in relation to impaired glucose metabolism and type 2 diabetes mellitus: the Maastricht Study.

    Science.gov (United States)

    Eussen, Simone J P M; van Dongen, Martien C J M; Wijckmans, Nicole; den Biggelaar, Louise; Oude Elferink, Stefanie J W H; Singh-Povel, Cécile M; Schram, Miranda T; Sep, Simone J S; van der Kallen, Carla J; Koster, Annemarie; Schaper, Nicolaas; Henry, Ronald M A; Stehouwer, Coen D A; Dagnelie, Pieter C

    2016-04-01

    Observational studies suggest an inverse association between total dairy product intake and diabetes risk. However, there is a lack of information on the relationship of specific dairy products with impaired glucose metabolism (IGM) and type 2 diabetes mellitus (T2DM). Individuals aged 40-75 years were recruited for the Maastricht Study. All the participants filled out a 253-food item FFQ, covering fifty specific dairy items that captured differences between full-fat, semi-skimmed and skimmed products, as well as fermented and non-fermented products. Glucose metabolism status was assessed by an oral glucose tolerance test, and participants were informed on their glucose metabolism status after returning the FFQ. Data of 2391 individuals were available to estimate OR (95 % CI) for IGM (n 470) and newly diagnosed (ND) T2DM (n 125), with adjustment for age, sex, BMI, physical activity, smoking status, education, energy intake and intakes of vegetables, fruits, meat and fish. For IGM, fully adjusted analyses revealed inverse associations, with OR comparing the highest with the lowest tertile of intake of 0·73 (95 % CI 0·55, 0·96) for skimmed products and 0·74 (95 % CI 0·54, 0·99) for fermented products. These dairy products were not associated with ND T2DM. In contrast, full-fat products were positively associated with ND T2DM (OR 2·01; 95 % CI 1·16, 3·47), whereas total dairy product intake was inversely associated with ND T2DM (OR 0·50; 95 % CI 0·26, 0·93). In conclusion, individuals with a high consumption of skimmed and fermented products had lower odds of having IGM, and individuals with a high consumption of total dairy products had lower odds of having ND T2DM. High intake of full-fat products was not related to IGM but was positively related to ND T2DM.

  14. 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....

  15. 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.

  16. 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

  17. PTENα, a PTEN isoform translated through alternative initiation, regulates mitochondrial function and energy metabolism.

    Science.gov (United States)

    Liang, Hui; He, Shiming; Yang, Jingyi; Jia, Xinying; Wang, Pan; Chen, Xi; Zhang, Zhong; Zou, Xiajuan; McNutt, Michael A; Shen, Wen Hong; Yin, Yuxin

    2014-05-06

    PTEN is one of the most frequently mutated genes in human cancer. It is known that PTEN has a wide range of biological functions beyond tumor suppression. Here, we report that PTENα, an N-terminally extended form of PTEN, functions in mitochondrial metabolism. Translation of PTENα is initiated from a CUG codon upstream of and in-frame with the coding region of canonical PTEN. Eukaryotic translation initiation factor 2A (eIF2A) controls PTENα translation, which requires a CUG-centered palindromic motif. We show that PTENα induces cytochrome c oxidase activity and ATP production in mitochondria. TALEN-mediated somatic deletion of PTENα impairs mitochondrial respiratory chain function. PTENα interacts with canonical PTEN to increase PINK1 protein levels and promote energy production. Our studies demonstrate the importance of eIF2A-mediated alternative translation for generation of protein diversity in eukaryotic systems and provide insights into the mechanism by which the PTEN family is involved in multiple cellular processes. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Diet-induced obesity impairs endometrial stromal cell decidualization: a potential role for impaired autophagy.

    Science.gov (United States)

    Rhee, Julie S; Saben, Jessica L; Mayer, Allyson L; Schulte, Maureen B; Asghar, Zeenat; Stephens, Claire; Chi, Maggie M-Y; Moley, Kelle H

    2016-06-01

    What effect does diet-induced obesity have on endometrial stromal cell (ESC) decidualization? Diet-induced obesity impairs ESC decidualization. Decidualization is important for successful implantation and subsequent health of the pregnancy. Compared with normal-weight women, obese women have lower pregnancy rates (both spontaneous and by assisted reproductive technology), higher rates of early pregnancy loss and poorer oocyte quality. Beginning at 6 weeks of age, female C57Bl/6J mice were fed either a high-fat/high-sugar diet (HF/HS; 58% Fat Energy/Sucrose) or a diet of standard mouse chow (CON; 13% Fat) for 12 weeks. At this point, metabolic parameters were measured. Some of the mice (n = 9 HF/HS and 9 CON) were mated with reproductively competent males, and implantation sites were assessed. Other mice (n = 11 HF/HS and 10 CON) were mated with vasectomized males, and artificial decidualization was induced. For in vitro human studies of primary ESCs, endometrial tissue was obtained via biopsy from normo-ovulatory patients without history of infertility (obese = BMI > 30 kg/m(2), n = 11 and lean = BMI treatment with cAMP and medroxyprogesterone. The level of expression of decidualization markers was assessed by RT-qPCR (mRNA) and western blotting (protein). ATP content of ESCs was measured, and levels of autophagy were assessed by western blotting of the autophagy regulators acetyl coa carboxylase (ACC) and ULK1 (Ser 317). Autophagic flux was measured by western blot of the marker LC3b-II. Mice exposed to an HF/HS diet became obese and metabolically impaired. HF/HS-exposed mice mated to reproductively competent males had smaller implantation sites in early pregnancy (P obese women than in those of normal-weight women (Ptreatment abrogated this increase. Many aspects of obesity and metabolic impairment could contribute to the decidualization defects observed in the HF/HS-exposed mice. Although our findings suggest that both autophagy and decidualization are impaired

  19. 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.

  20. 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.

  1. [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.

  2. 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....

  3. 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.

  4. Plasma antioxidants and brain glucose metabolism in elderly subjects with cognitive complaints

    Energy Technology Data Exchange (ETDEWEB)

    Picco, Agnese; Ferrara, Michela; Arnaldi, Dario; Brugnolo, Andrea; Nobili, Flavio [University of Genoa and IRCCS San Martino-IST, Clinical Neurology, Department of Neuroscience (DINOGMI), Largo P. Daneo, 3, 16132, Genoa (Italy); Polidori, M.C. [University of Cologne, Institute of Geriatrics, Cologne (Germany); Cecchetti, Roberta; Baglioni, Mauro; Bastiani, Patrizia; Mecocci, Patrizia [University of Perugia, Institute of Gerontology and Geriatrics, Department of Clinical and Experimental Medicine, Perugia (Italy); Morbelli, Silvia; Bossert, Irene [University of Genoa and IRCCS San Martino-IST, Nuclear Medicine, Department of Health Science (DISSAL), Genoa (Italy); Fiorucci, Giuliana; Dottorini, Massimo Eugenio [Nuclear Medicine, S. M. della Misericordia Hospital, Perugia (Italy)

    2014-04-15

    The role of oxidative stress is increasingly recognized in cognitive disorders of the elderly, notably Alzheimer's disease (AD). In these subjects brain{sup 18}F-FDG PET is regarded as a reliable biomarker of neurodegeneration. We hypothesized that oxidative stress could play a role in impairing brain glucose utilization in elderly subjects with increasing severity of cognitive disturbance. The study group comprised 85 subjects with cognitive disturbance of increasing degrees of severity including 23 subjects with subjective cognitive impairment (SCI), 28 patients with mild cognitive impairment and 34 patients with mild AD. In all subjects brain FDG PET was performed and plasma activities of extracellular superoxide dismutase (eSOD), catalase and glutathione peroxidase were measured. Voxel-based analysis (SPM8) was used to compare FDG PET between groups and to evaluate correlations between plasma antioxidants and glucose metabolism in the whole group of subjects, correcting for age and Mini-Mental State Examination score. Brain glucose metabolism progressively decreased in the bilateral posterior temporoparietal and cingulate cortices across the three groups, from SCI to mild AD. eSOD activity was positively correlated with glucose metabolism in a large area of the left temporal lobe including the superior, middle and inferior temporal gyri and the fusiform gyrus. These results suggest a role of oxidative stress in the impairment of glucose utilization in the left temporal lobe structures in elderly patients with cognitive abnormalities, including AD and conditions predisposing to AD. Further studies exploring the oxidative stress-energy metabolism axis are considered worthwhile in larger groups of these patients in order to identify pivotal pathophysiological mechanisms and innovative therapeutic opportunities. (orig.)

  5. Plasma antioxidants and brain glucose metabolism in elderly subjects with cognitive complaints

    International Nuclear Information System (INIS)

    Picco, Agnese; Ferrara, Michela; Arnaldi, Dario; Brugnolo, Andrea; Nobili, Flavio; Polidori, M.C.; Cecchetti, Roberta; Baglioni, Mauro; Bastiani, Patrizia; Mecocci, Patrizia; Morbelli, Silvia; Bossert, Irene; Fiorucci, Giuliana; Dottorini, Massimo Eugenio

    2014-01-01

    The role of oxidative stress is increasingly recognized in cognitive disorders of the elderly, notably Alzheimer's disease (AD). In these subjects brain 18 F-FDG PET is regarded as a reliable biomarker of neurodegeneration. We hypothesized that oxidative stress could play a role in impairing brain glucose utilization in elderly subjects with increasing severity of cognitive disturbance. The study group comprised 85 subjects with cognitive disturbance of increasing degrees of severity including 23 subjects with subjective cognitive impairment (SCI), 28 patients with mild cognitive impairment and 34 patients with mild AD. In all subjects brain FDG PET was performed and plasma activities of extracellular superoxide dismutase (eSOD), catalase and glutathione peroxidase were measured. Voxel-based analysis (SPM8) was used to compare FDG PET between groups and to evaluate correlations between plasma antioxidants and glucose metabolism in the whole group of subjects, correcting for age and Mini-Mental State Examination score. Brain glucose metabolism progressively decreased in the bilateral posterior temporoparietal and cingulate cortices across the three groups, from SCI to mild AD. eSOD activity was positively correlated with glucose metabolism in a large area of the left temporal lobe including the superior, middle and inferior temporal gyri and the fusiform gyrus. These results suggest a role of oxidative stress in the impairment of glucose utilization in the left temporal lobe structures in elderly patients with cognitive abnormalities, including AD and conditions predisposing to AD. Further studies exploring the oxidative stress-energy metabolism axis are considered worthwhile in larger groups of these patients in order to identify pivotal pathophysiological mechanisms and innovative therapeutic opportunities. (orig.)

  6. 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...

  7. 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

  8. 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.

  9. EXPERIMENTAL WORK AND RESEARCH Effect of Tiaoxin Recipe(调心方)on Spatial Memory and Energy Metabolism of Oxidation Injured Alzheimers Disease Rats

    Institute of Scientific and Technical Information of China (English)

    QIUHong; ZHAOWei-kang; 等

    2003-01-01

    Objective:To observe the effect of Tiaoxin Recipe(TXR) on the spatial memory,brain mitochondrial energy metabolism of oxidation injured Alzheimer's disease(AD) rats,and to explore the mechanism of TXR in treating AD.Methods:Eighty-eight SD rats were randomly divided into five groups (normal group,operative group,“AD”model group,TXR group and Aricept group).An oxygen free rad-ical generation system (dihydroxy fumaric acid-trichloroferric-adenosine diphosphate,DHF-FeCl3-ADP)was used to create oxidation injured rat models mimic to AD; spatial learning and memeory impairment (Morris water maze method),the activity of Succinate-oxidase,NADH-oxidase,CytC-oxidase(Clark ox-ygen electrode method)and the expression of cytochrome oxidase(CO)ⅡmRNA(in situ hybridization method)were observed.Results:Compared with the normal group,the spatial memory,activity of CytC-oxidase and COⅡmRNA expression of oxidation injured“AD”rats were obviously decreased;TXR,how-ever,could improve these functions in “AD”rat models obviously.Conclusion:The mechanism of the ac-tion of TXR in treating AD was partly related to its effect on anti-oxidation which could improve brain mi-tochondrial energy metabolism.

  10. 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

  11. 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.

  12. Sleep apnea predicts distinct alterations in glucose homeostasis and biomarkers in obese adults with normal and impaired glucose metabolism

    Directory of Open Access Journals (Sweden)

    Hill Nathan R

    2010-12-01

    Full Text Available Abstract Background Notwithstanding previous studies supporting independent associations between obstructive sleep apnea (OSA and prevalence of diabetes, the underlying pathogenesis of impaired glucose regulation in OSA remains unclear. We explored mechanisms linking OSA with prediabetes/diabetes and associated biomarker profiles. We hypothesized that OSA is associated with distinct alterations in glucose homeostasis and biomarker profiles in subjects with normal (NGM and impaired glucose metabolism (IGM. Methods Forty-five severely obese adults (36 women without certain comorbidities/medications underwent anthropometric measurements, polysomnography, and blood tests. We measured fasting serum glucose, insulin, selected cytokines, and calculated homeostasis model assessment estimates of insulin sensitivity (HOMA-IS and pancreatic beta-cell function (HOMA-B. Results Both increases in apnea-hypopnea index (AHI and the presence of prediabetes/diabetes were associated with reductions in HOMA-IS in the entire cohort even after adjustment for sex, race, age, and BMI (P = 0.003. In subjects with NGM (n = 30, OSA severity was associated with significantly increased HOMA-B (a trend towards decreased HOMA-IS independent of sex and adiposity. OSA-related oxyhemoglobin desaturations correlated with TNF-α (r=-0.76; P = 0.001 in women with NGM and with IL-6 (rho=-0.55; P = 0.035 in women with IGM (n = 15 matched individually for age, adiposity, and AHI. Conclusions OSA is independently associated with altered glucose homeostasis and increased basal beta-cell function in severely obese adults with NGM. The findings suggest that moderate to severe OSA imposes an excessive functional demand on pancreatic beta-cells, which may lead to their exhaustion and impaired secretory capacity over time. The two distinct biomarker profiles linking sleep apnea with NGM and IGM via TNF-α and IL-6 have been discerned in our study to suggest that sleep apnea and particularly

  13. Impaired Glucose Metabolism Despite Decreased Insulin Resistance After Renal Transplantation

    Directory of Open Access Journals (Sweden)

    Manfred Hecking

    2012-06-01

    Full Text Available The pathophysiology underlying new-onset diabetes after transplantation (NODAT is unresolved. We obtained demographics and laboratory data from all 1064 renal transplant recipients followed at our outpatient clinic in 2009/2010, randomly assigned 307 patients without previously diagnosed diabetes to a routine 2-hour oral glucose tolerance test (OGTT, and compared the metabolic results to a large, unrelated cross-sectional cohort of non-transplanted subjects. Among renal transplant recipients, 11% had a history of NODAT, and 12% had type 1 and type 2 diabetes. 42% of all OGTTs were abnormal (9% diabetic, predominantly in older patients who received tacrolimus. Compared to non-transplanted subjects, basal glucose was lower and HbA1c higher in renal transplant patients. Compared to non-transplanted subjects, insulin secretion was inferior, and insulin sensitivity improved at ≥6 months, as well as 3 months post-transplantation:(The Figure shows linear spline interpolation; all p for overall difference between non-Tx and Tx patients <0.02, using likelihood ratio testing. Our results indicate that impaired insulin secretion is the predominant problem after renal transplantation, suggesting benefit for therapeutic regimens that preserve beta cell function after renal transplantation. The mechanism of increased insulin sensitivity might be pathophysiologically similar to pancreatogenic diabetes.fx1

  14. Mitochondrial metabolism in early neural fate and its relevance for neuronal disease modeling.

    Science.gov (United States)

    Lorenz, Carmen; Prigione, Alessandro

    2017-12-01

    Modulation of energy metabolism is emerging as a key aspect associated with cell fate transition. The establishment of a correct metabolic program is particularly relevant for neural cells given their high bioenergetic requirements. Accordingly, diseases of the nervous system commonly involve mitochondrial impairment. Recent studies in animals and in neural derivatives of human pluripotent stem cells (PSCs) highlighted the importance of mitochondrial metabolism for neural fate decisions in health and disease. The mitochondria-based metabolic program of early neurogenesis suggests that PSC-derived neural stem cells (NSCs) may be used for modeling neurological disorders. Understanding how metabolic programming is orchestrated during neural commitment may provide important information for the development of therapies against conditions affecting neural functions, including aging and mitochondrial disorders. Copyright © 2017. Published by Elsevier Ltd.

  15. 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

  16. 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.

  17. 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...

  18. Deletion of GLUT1 and GLUT3 Reveals Multiple Roles for Glucose Metabolism in Platelet and Megakaryocyte Function

    Directory of Open Access Journals (Sweden)

    Trevor P. Fidler

    2017-07-01

    Full Text Available Anucleate platelets circulate in the blood to facilitate thrombosis and diverse immune functions. Platelet activation leading to clot formation correlates with increased glycogenolysis, glucose uptake, glucose oxidation, and lactic acid production. Simultaneous deletion of glucose transporter (GLUT 1 and GLUT3 (double knockout [DKO] specifically in platelets completely abolished glucose uptake. In DKO platelets, mitochondrial oxidative metabolism of non-glycolytic substrates, such as glutamate, increased. Thrombosis and platelet activation were decreased through impairment at multiple activation nodes, including Ca2+ signaling, degranulation, and integrin activation. DKO mice developed thrombocytopenia, secondary to impaired pro-platelet formation from megakaryocytes, and increased platelet clearance resulting from cytosolic calcium overload and calpain activation. Systemic treatment with oligomycin, inhibiting mitochondrial metabolism, induced rapid clearance of platelets, with circulating counts dropping to zero in DKO mice, but not wild-type mice, demonstrating an essential role for energy metabolism in platelet viability. Thus, substrate metabolism is essential for platelet production, activation, and survival.

  19. 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.

  20. Anthropometric indices are not satisfactory predictors of metabolic comorbidities in obese children and adolescents.

    Science.gov (United States)

    Morandi, Anita; Miraglia Del Giudice, Emanuele; Martino, Francesco; Martino, Eliana; Bozzola, Mauro; Maffeis, Claudio

    2014-12-01

    To assess the accuracy of body mass index (BMI), Z score of the BMI, waist circumference, and waist-to-height ratio in selecting obese children with fasting metabolic impairments or impaired glucose tolerance. In a cohort of 883 obese children and adolescents (age 8-18 years), we assessed the associations of anthropometric indices with traditional metabolic complications of obesity (impaired fasting glucose, impaired glucose tolerance, hypertension, high triglycerides, low high-density lipoprotein-cholesterol). The accuracy of anthropometric indices as markers of metabolic impairment was assessed by receiver operating characteristic analysis and the areas under the receiver operating characteristics curves (AUROCs) of anthropometric indices were compared with each other by the DeLong test. BMI, Z score of the BMI, waist circumference, and waist-to-height ratio were associated with metabolic impairments but showed low to moderate accuracy in discriminating both single and clustered metabolic impairments. The AUROCs ranged from 0.55-0.70. The 4 anthropometric indices did not show significantly different AUROCs as predictors of clustered metabolic risk factors (all P values of DeLong tests: >.05). Commonly used anthropometric indices are not satisfactory markers of metabolic comorbidity among obese children and adolescents and should not be adopted as screening tools for the metabolic assessment of this category of patients. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Impaired arsenic metabolism in children during weaning

    International Nuclear Information System (INIS)

    Faengstroem, Britta; Hamadani, Jena; Nermell, Barbro; Grander, Margaretha; Palm, Brita; Vahter, Marie

    2009-01-01

    Background: Methylation of inorganic arsenic (iAs) via one-carbon metabolism is a susceptibility factor for a range of arsenic-related health effects, but there is no data on the importance of arsenic metabolism for effects on child development. Aim: To elucidate the development of arsenic metabolism in early childhood. Methods: We measured iAs, methylarsonic acid (MA) and dimethylarsinic acid (DMA), the metabolites of iAs, in spot urine samples of 2400 children at 18 months of age. The children were born to women participating in a population-based longitudinal study of arsenic effects on pregnancy outcomes and child development, carried out in Matlab, a rural area in Bangladesh with a wide range of arsenic concentrations in drinking water. Arsenic metabolism was evaluated in relation to age, sex, anthropometry, socio-economic status and arsenic exposure. Results: Arsenic concentrations in child urine (median 34 μg/L, range 2.4-940 μg/L), adjusted to average specific gravity of 1.009 g/mL, were considerably higher than that measured at 3 months of age, but lower than that in maternal urine. Child urine contained on average 12% iAs, 9.4% MA and 78% DMA, which implies a marked change in metabolite pattern since infancy. In particular, there was a marked increase in urinary %MA, which has been associated with increased risk of health effects. Conclusion: The arsenic metabolite pattern in urine of children at 18 months of age in rural Bangladesh indicates a marked decrease in arsenic methylation efficiency during weaning.

  2. 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.

  3. 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.

  4. 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.

  5. Exercise training in Tgαq*44 mice during the progression of chronic heart failure: cardiac vs. peripheral (soleus muscle) impairments to oxidative metabolism.

    Science.gov (United States)

    Grassi, Bruno; Majerczak, Joanna; Bardi, Eleonora; Buso, Alessia; Comelli, Marina; Chlopicki, Stefan; Guzik, Magdalena; Mavelli, Irene; Nieckarz, Zenon; Salvadego, Desy; Tyrankiewicz, Urszula; Skórka, Tomasz; Bottinelli, Roberto; Zoladz, Jerzy A; Pellegrino, Maria Antonietta

    2017-08-01

    Cardiac function, skeletal (soleus) muscle oxidative metabolism, and the effects of exercise training were evaluated in a transgenic murine model (Tgα q *44) of chronic heart failure during the critical period between the occurrence of an impairment of cardiac function and the stage at which overt cardiac failure ensues (i.e., from 10 to 12 mo of age). Forty-eight Tgα q *44 mice and 43 wild-type FVB controls were randomly assigned to control groups and to groups undergoing 2 mo of intense exercise training (spontaneous running on an instrumented wheel). In mice evaluated at the beginning and at the end of training we determined: exercise performance (mean distance covered daily on the wheel); cardiac function in vivo (by magnetic resonance imaging); soleus mitochondrial respiration ex vivo (by high-resolution respirometry); muscle phenotype [myosin heavy chain (MHC) isoform content; citrate synthase (CS) activity]; and variables related to the energy status of muscle fibers [ratio of phosphorylated 5'-AMP-activated protein kinase (AMPK) to unphosphorylated AMPK] and mitochondrial biogenesis and function [peroxisome proliferative-activated receptor-γ coactivator-α (PGC-1α)]. In the untrained Tgα q *44 mice functional impairments of exercise performance, cardiac function, and soleus muscle mitochondrial respiration were observed. The impairment of mitochondrial respiration was related to the function of complex I of the respiratory chain, and it was not associated with differences in CS activity, MHC isoforms, p-AMPK/AMPK, and PGC-1α levels. Exercise training improved exercise performance and cardiac function, but it did not affect mitochondrial respiration, even in the presence of an increased percentage of type 1 MHC isoforms. Factors "upstream" of mitochondria were likely mainly responsible for the improved exercise performance. NEW & NOTEWORTHY Functional impairments in exercise performance, cardiac function, and soleus muscle mitochondrial respiration

  6. 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

  7. 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.

  8. A metabolic link to skeletal muscle wasting and regeneration

    Directory of Open Access Journals (Sweden)

    René eKoopman

    2014-02-01

    Full Text Available Due to its essential role in movement, insulating the internal organs, generating heat to maintain core body temperature, and acting as a major energy storage depot, any impairment to skeletal muscle structure and function may lead to an increase in both morbidity and mortality. In the context of skeletal muscle, altered metabolism is directly associated with numerous pathologies and disorders, including diabetes, and obesity, while many skeletal muscle pathologies have secondary changes in metabolism, including cancer cachexia, sarcopenia and the muscular dystrophies. Furthermore, the importance of cellular metabolism in the regulation of skeletal muscle stem cells is beginning to receive significant attention. Thus, it is clear that skeletal muscle metabolism is intricately linked to the regulation of skeletal muscle mass and regeneration. The aim of this review is to discuss some of the recent findings linking a change in metabolism to changes in skeletal muscle mass, as well as describing some of the recent studies in developmental, cancer and stem-cell biology that have identified a role for cellular metabolism in the regulation of stem cell function, a process termed ‘metabolic reprogramming’.

  9. Caloric Restriction Promotes Structural and Metabolic Changes in the Skin

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Forni

    2017-09-01

    Full Text Available Caloric restriction (CR is the most effective intervention known to enhance lifespan, but its effect on the skin is poorly understood. Here, we show that CR mice display fur coat remodeling associated with an expansion of the hair follicle stem cell (HFSC pool. We also find that the dermal adipocyte depot (dWAT is underdeveloped in CR animals. The dermal/vennule annulus vasculature is enlarged, and a vascular endothelial growth factor (VEGF switch and metabolic reprogramming in both the dermis and the epidermis are observed. When the fur coat is removed, CR mice display increased energy expenditure associated with lean weight loss and locomotion impairment. Our findings indicate that CR promotes extensive skin and fur remodeling. These changes are necessary for thermal homeostasis and metabolic fitness under conditions of limited energy intake, suggesting a potential adaptive mechanism.

  10. Chronic pyruvate supplementation increases exploratory activity and brain energy reserves in young and middle-aged mice

    Directory of Open Access Journals (Sweden)

    Hennariikka eKoivisto

    2016-03-01

    Full Text Available Numerous studies have reported neuroprotective effects of pyruvate when given in systemic injections. Impaired glucose uptake and metabolism are found in Alzheimer's disease (AD and in AD mouse models. We tested whether dietary pyruvate supplementation is able to provide added energy supply to brain and thereby attenuate aging- or AD-related cognitive impairment. Mice received ~ 800 mg/kg/day Na-pyruvate in their chow for 2- 6 months. In middle-aged wild-type mice and in 6.5-month-old APP/PS1 mice, pyruvate facilitated spatial learning and increased exploration of a novel odor. However, in passive avoidance task for fear memory, the treatment group was clearly impaired. Independent of age, long-term pyruvate increased explorative behavior, which likely explains the paradoxical impairment in passive avoidance. We also assessed pyruvate effects on body weight, muscle force and endurance, and found no effects. Metabolic post-mortem assays revealed increased energy compounds in nuclear magnetic resonance spectroscopy as well as increased brain glycogen storages in the pyruvate group. Pyruvate supplementation may counteract aging-related behavioral impairment but its beneficial effect seems related to increased explorative activity rather than direct memory enhancement.

  11. 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.

  12. Interplay Between Diet, Gut Microbiota, Immune Cells and Energy Metabolism in Obesity Development

    DEFF Research Database (Denmark)

    Danneskiold-Samsøe, Niels Banhos

    Obesity and associated metabolic disorders such as type 2 diabetes are major causes of morbidity and mortality globally. A major contributor to development of the obesity pandemic has been the increasing intake of energy dense diets, consisting of dietary fats combined with high-glycemic carbohyd......Obesity and associated metabolic disorders such as type 2 diabetes are major causes of morbidity and mortality globally. A major contributor to development of the obesity pandemic has been the increasing intake of energy dense diets, consisting of dietary fats combined with high......-glycemic carbohydrates such as refined grains and sugars. The lack of sufficient therapeutic options for obesity, and the inability of most individuals to reduce energy intake or increase expenditure highlight the importance of understanding its underlying biological mechanisms. Obesity is associated with low...... in glucose intolerance without inflammatory changes in visceral fat or the liver, but with changes to the gut microbiota. Finally we find that fat cell specific activity of cyclooxygenase-2, an enzyme important for metabolism of fat, decreases body fat mass and increases insulin sensitivity associated...

  13. Changes in cognitive function and brain glucose metabolism in elderly women with subjective memory impairment: a 24-month prospective pilot study.

    Science.gov (United States)

    Jeong, H S; Park, J S; Song, I U; Chung, Y A; Rhie, S J

    2017-01-01

    Subjective memory impairment (SMI) may precede mild cognitive impairment (MCI) stage and would offer an earlier therapeutic opportunity than MCI would. However, it is not clear whether complaints of forgetfulness are truly reflective of objective memory dysfunction or of impairments in other cognitive domains. The aim of this current longitudinal study was to investigate changes in various cognitive functions and in regional cerebral metabolic rate of glucose (rCMRglc) among elderly women with SMI. Clinical evaluation, comprehensive neuropsychological test, and 18 F-fluoro-2-deoxyglucose positron emission tomography scans were conducted on 24 women with SMI at the baseline and 24-month follow-up. Changes in the cognitive domain scores and rCMRglc were assessed, and the relationships between them were analyzed. All participants stayed in SMI all the way till the follow-up, not converted to MCI or dementia. A significant reduction in executive function was found (mean difference in z-score: -0.21, P = 0.02) without changes in other cognitive domains. Declines in rCMRglc were detected in the left superior temporal gyrus, right posterior cingulate gyrus, left parahippocampal gyrus, right lingual gyrus, and right angular gyrus. The change in executive function had a positive correlation with the percent change of rCMRglc in the right posterior cingulate gyrus (β = 0.43, P = 0.02). Our findings suggest that elderly women with SMI symptoms should be carefully monitored for declines in executive function and related brain glucose metabolism over time. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Muscle insulin sensitivity and glucose metabolism are controlled by the intrinsic muscle clock★

    Science.gov (United States)

    Dyar, Kenneth A.; Ciciliot, Stefano; Wright, Lauren E.; Biensø, Rasmus S.; Tagliazucchi, Guidantonio M.; Patel, Vishal R.; Forcato, Mattia; Paz, Marcia I.P.; Gudiksen, Anders; Solagna, Francesca; Albiero, Mattia; Moretti, Irene; Eckel-Mahan, Kristin L.; Baldi, Pierre; Sassone-Corsi, Paolo; Rizzuto, Rosario; Bicciato, Silvio; Pilegaard, Henriette; Blaauw, Bert; Schiaffino, Stefano

    2013-01-01

    Circadian rhythms control metabolism and energy homeostasis, but the role of the skeletal muscle clock has never been explored. We generated conditional and inducible mouse lines with muscle-specific ablation of the core clock gene Bmal1. Skeletal muscles from these mice showed impaired insulin-stimulated glucose uptake with reduced protein levels of GLUT4, the insulin-dependent glucose transporter, and TBC1D1, a Rab-GTPase involved in GLUT4 translocation. Pyruvate dehydrogenase (PDH) activity was also reduced due to altered expression of circadian genes Pdk4 and Pdp1, coding for PDH kinase and phosphatase, respectively. PDH inhibition leads to reduced glucose oxidation and diversion of glycolytic intermediates to alternative metabolic pathways, as revealed by metabolome analysis. The impaired glucose metabolism induced by muscle-specific Bmal1 knockout suggests that a major physiological role of the muscle clock is to prepare for the transition from the rest/fasting phase to the active/feeding phase, when glucose becomes the predominant fuel for skeletal muscle. PMID:24567902

  15. 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

  16. Correlação entre tontura e disfunções do metabolismo da glicose Correlation between dizziness and impaired glucose metabolism

    Directory of Open Access Journals (Sweden)

    Adriano Santana Fonseca

    2006-06-01

    Full Text Available INTRODUÇÃO: as alterações do metabolismo da glicose são caracterizadas por estados de hipoglicemia e hiperglicemia. OBJETIVO: A proposta deste trabalho é verificar a associação entre as alterações do metabolismo da glicose, por glicemia de jejum e teste de tolerância à glicose e à tontura, avaliada por sua queixa e exames clínicos e subsidiários. MÉTODO: O estudo foi efetivado num grupo de 33 pacientes divididos em 3 subgrupos: pacientes com queixa de tontura, pacientes diabéticos e pacientes assintomáticos. RESULTADOS: O grupo de pacientes com queixa espontânea ou questionada de tontura apresentava alterações no metabolismo da glicose em 65% dos casos. Já entre os pacientes dos 3 grupos sem queixa de tontura, 30% apresentavam alterações do metabolismo da glicose. 40% dos pacientes que apresentaram queixas de tonturas tinham o exame vestibular clínico e a vectoeletronistagmografia alterados, enquanto que entre os assintomáticos 7,5% apresentaram as alterações vestibulares referidas. CONCLUSÃO: A tontura é um bom indicador de alteração do metabolismo da glicose e a alteração do metabolismo da glicose é um bom indicador de alteração do exame vestibular. O estudo do metabolismo da glicose a partir dos níveis glicêmicos é eficaz e tem resultados próximos dos observados nos estudos que mensuram os níveis insulinêmicos.INTRODUCTION: Impaired glucose metabolism is characterized by conditions of hypo and hyperglycemia. AIM: The objective of the present study was to asses whether or not there is a relationship between impaired glucose metabolism and dizziness. In the clinical laboratory settings, patients were examined using vectoelectronystagmography in association with glycemic levels. METHODS: 33 patients were divided in 3 groups: diabetics; patients with dizziness and a control group. RESULTS: 65% of the patients with dizziness showed impaired glucose metabolism. 40% of the patients with dizziness had

  17. 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.

  18. Impaired intestinal wound healing in Fhl2-deficient mice is due to disturbed collagen metabolism

    International Nuclear Information System (INIS)

    Kirfel, Jutta; Pantelis, Dimitrios; Kabba, Mustapha; Kahl, Philip; Roeper, Anke; Kalff, Joerg C.; Buettner, Reinhard

    2008-01-01

    Four and one half LIM domain protein FHL2 participates in many cellular processes involved in tissue repair such as regulation of gene expression, cytoarchitecture, cell adhesion, migration and signal transduction. The repair process after wounding is initiated by the release of peptides and bioactive lipids. These molecules induce synthesis and deposition of a provisional extracellular matrix. We showed previously that sphingosine-1-phosphate (S1P) triggers a signal transduction cascade mediating nuclear translocation of FHL2 in response to activation of the RhoA GTPase. Our present study shows that FHL2 is an important signal transducer influencing the outcome of intestinal anastomotic healing. Early wound healing is accompanied by reconstitution and remodelling of the extracellular matrix and collagen is primarily responsible for wound strength. Our results show that impaired intestinal wound healing in Fhl2-deficient mice is due to disturbed collagen III metabolism. Impaired collagen III synthesis reduced the mechanical stability of the anastomoses and led to lower bursting pressure in Fhl2-deficient mice after surgery. Our data confirm that FHL2 is an important factor regulating collagen expression in the early phase of wound healing, and thereby is critically involved in the physiologic process of anastomosis healing after bowel surgery and thus may represent a new therapeutic target

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. New peptides players in metabolic disorders

    Directory of Open Access Journals (Sweden)

    Agata Mierzwicka

    2016-08-01

    Full Text Available Among new peptides responsible for the pathogenesis of metabolic disorders and carbohydrate metabolism, adipokines are of great importance. Adipokines are substances of hormonal character, secreted by adipose tissue. Apart from the well-known adipokines, adropin and preptin are relatively newly discovered, hence their function is not fully understood. They are peptides not secreted by adipose tissue but their role in the metabolic regulations seems to be significant. Preptin is a 34-amino acid peptide, a derivative of proinsulin growth factor II (pro-IGF-II, secreted by pancreatic β cells, considered to be a physiological enhancer of insulin secretion. Additionally, preptin has a stimulating effect on osteoblasts, inducing their proliferation, differentiation and survival. Adropin is a 76-amino acid peptide, encoded by the energy homeostasis associated gene (Enho, mainly in liver and brain, and its expression is dependent on a diet. Adropin is believed to play an important role in metabolic homeostasis, fatty acids metabolism control, insulin resistance prevention, dyslipidemia, and impaired glucose tolerance. The results of studies conducted so far show that the diseases resulting from metabolic syndrome, such as obesity, type 2 diabetes mellitus, polycystic ovary syndrome, non-alcoholic fatty liver disease, or cardiovascular disease are accompanied by significant changes in the concentration of these peptides. It is also important to note that preptin has an anabolic effect on bone tissue, which might be preventive in osteoporosis.

  4. High fructose corn syrup induces metabolic dysregulation and altered dopamine signaling in the absence of obesity

    OpenAIRE

    Meyers, Allison M.; Mourra, Devry; Beeler, Jeff A.

    2017-01-01

    The contribution of high fructose corn syrup (HFCS) to metabolic disorder and obesity, independent of high fat, energy-rich diets, is controversial. While high-fat diets are widely accepted as a rodent model of diet-induced obesity (DIO) and metabolic disorder, the value of HFCS alone as a rodent model of DIO is unclear. Impaired dopamine function is associated with obesity and high fat diet, but the effect of HFCS on the dopamine system has not been investigated. The objective of this study ...

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Integrative Control of Energy Balance and Reproduction in Females

    OpenAIRE

    Garcia-Garcia, R. M.

    2012-01-01

    There is a strong association between nutrition and reproduction. Chronic dietary energy deficits as well as energy surpluses can impair reproductive capacity. Metabolic status impacts reproductive function at systemic level, modulating the hypothalamic GnRH neuronal network and/or the pituitary gonadotropin secretion through several hormones and neuropeptides, and at the ovarian level, acting through the regulation of follicle growth and steroidogenesis by means of the growth hormone-IGF-ins...

  12. Insulin resistance in human subjects having impaired glucose regulation

    International Nuclear Information System (INIS)

    Khan, S.H.; Khan, F.A.; Ijaz, A.

    2007-01-01

    To determine insulin resistance in human subjects having impaired glucose regulation (IGR) by Homeostasis Model Assessment for Insulin Resistance (HOMA-IR). A total of 100 subjects with impaired glucose regulation were selected for evaluation of metabolic syndrome as per the criteria of National Cholesterol Education Program, Adult Treatment Panel III (NCEP, ATP III), along with 47 healthy age and gender-matched controls. Physical examination to determine blood pressure and waist circumference was carried out and so was sampling for plasma glucose, serum triglycerides, HDL-cholesterol and insulin. Insulin resistance was calculated by the HOMA-IR. Finally, subjects with and without metabolic syndrome were compared with controls (n=47), using one-way ANOVA for studying insulin resistance between groups, with Tukey's post-hoc comparison. The frequency of finding metabolic syndrome in cases of IGR remained 47%. The insulin resistance demonstrated stepwise worsening from control population (mean=1.54, 95 % CI: 1.77 - 2.37) to subjects suffering from only IGR (mean=2.07, 95 % CI: 1.77- 2.37) to metabolic syndrome (mean=2.67, 95 %, CI: 2.34 - 3.00) (p < 0.001). Patients with impaired glucose regulation may have significant insulin resistance. It is, thus, recommended that a vigorous search be made to measure insulin resistance in all cases diagnosed to have impaired glucose regulation. (author)

  13. Mechanisms by Which Metabolic Reprogramming in GSD1 Liver Generates a Favorable Tumorigenic Environment

    Directory of Open Access Journals (Sweden)

    Monika Gjorgjieva PhD Student

    2016-11-01

    Full Text Available Glycogen storage disease type 1 (GSD1 is an inherited disorder caused by impaired glucose 6-phosphatase activity. This impairment translates into the inhibition of endogenous glucose production and the subsequent accumulation of cellular glucose 6-phosphate. Excess glucose 6-phosphate enhances glycolysis, increases the production of fatty acids, uric acid, and lactate, causes hepatomegaly due to glycogen and lipid accumulation, and finally results in liver tumor development. Although the exact mechanisms of tumorigenesis in patients with GSD1 remain unclear, GSD1 hepatocytes undergo a Warburg-like metabolic switch. The consequent hyperactivation of specific metabolic pathways renders GSD1 hepatocytes susceptible to tumor development, presumably by providing the building blocks and energy required for cell proliferation. In addition to this, enhanced apoptosis in GSD1 may promote mitotic activity and hence result in DNA replication errors, thereby contributing to tumorigenesis. Increased carbohydrate responsive element-binding protein (ChREBP and mammalian target of rapamycin (mTOR activity and impaired AMP-activated protein kinase (AMPK function likely play key roles in these pro-oncogenic processes.

  14. 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

  15. 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) ...

  16. Anorexia and impaired glucose metabolism in mice with hypothalamic ablation of Glut4 neurons.

    Science.gov (United States)

    Ren, Hongxia; Lu, Taylor Y; McGraw, Timothy E; Accili, Domenico

    2015-02-01

    The central nervous system (CNS) uses glucose independent of insulin. Nonetheless, insulin receptors and insulin-responsive glucose transporters (Glut4) often colocalize in neurons (Glut4 neurons) in anatomically and functionally distinct areas of the CNS. The apparent heterogeneity of Glut4 neurons has thus far thwarted attempts to understand their function. To answer this question, we used Cre-dependent, diphtheria toxin-mediated cell ablation to selectively remove basal hypothalamic Glut4 neurons and investigate the resulting phenotypes. After Glut4 neuron ablation, mice demonstrate altered hormone and nutrient signaling in the CNS. Accordingly, they exhibit negative energy balance phenotype characterized by reduced food intake and increased energy expenditure, without locomotor deficits or gross neuronal abnormalities. Glut4 neuron ablation affects orexigenic melanin-concentrating hormone neurons but has limited effect on neuropeptide Y/agouti-related protein and proopiomelanocortin neurons. The food intake phenotype can be partially normalized by GABA administration, suggesting that it arises from defective GABAergic transmission. Glut4 neuron-ablated mice show peripheral metabolic defects, including fasting hyperglycemia and glucose intolerance, decreased insulin levels, and elevated hepatic gluconeogenic genes. We conclude that Glut4 neurons integrate hormonal and nutritional cues and mediate CNS actions of insulin on energy balance and peripheral metabolism. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  17. Benznidazole induces in vitro anaerobic metabolism in Trypanosoma cruzi epimastigotes

    Directory of Open Access Journals (Sweden)

    Marina Clare Vinaud

    2017-11-01

    Full Text Available Objective: To determine the biochemical alterations of the energetic metabolism of Trypanosoma cruzi epimastigotes in vitro exposed to different concentrations of benzinidazole. Methods: Biochemical analyses were performed at 3, 6 (log phase, 9 and 12 (stationary phase days of culture. Parasites were exposed to five concentrations of benzinidazole. Glycolysis, tricarboxilic acid cycle and fatty acids oxidation pathways were quantified through chromatography. Glucose, urea and creatinine were quantified through spectrophotometric analysis. Results: Anaerobic fermentation and fatty acids oxidation were increased in the stationary phase of the culture. Benzinidazole at high concentrations induced anaerobic metabolism in the log phase of the culture while the parasites exposed to the lower concentrations preferred the citric acid cycle as energy production pathway. Benzinidazole did not influence on the proteins catabolism. Conclusions: It is possible to conclude that there are metabolic differences between evolutive forms of Trypanosoma cruzi and the main drug used for its treatment induces the anaerobic metabolism in the parasite, possibly impairing the mitochondrial pathways.

  18. Endothelial cell energy metabolism, proliferation, and apoptosis in pulmonary hypertension.

    Science.gov (United States)

    Xu, Weiling; Erzurum, Serpil C

    2011-01-01

    Pulmonary arterial hypertension (PAH) is a fatal disease characterized by impaired regulation of pulmonary hemodynamics and excessive growth and dysfunction of the endothelial cells that line the arteries in PAH lungs. Establishment of methods for culture of pulmonary artery endothelial cells from PAH lungs has provided the groundwork for mechanistic translational studies that confirm and extend findings from model systems and spontaneous pulmonary hypertension in animals. Endothelial cell hyperproliferation, survival, and alterations of biochemical-metabolic pathways are the unifying endothelial pathobiology of the disease. The hyperproliferative and apoptosis-resistant phenotype of PAH endothelial cells is dependent upon the activation of signal transducer and activator of transcription (STAT) 3, a fundamental regulator of cell survival and angiogenesis. Animal models of PAH, patients with PAH, and human PAH endothelial cells produce low nitric oxide (NO). In association with the low level of NO, endothelial cells have reduced mitochondrial numbers and cellular respiration, which is associated with more than a threefold increase in glycolysis for energy production. The shift to glycolysis is related to low levels of NO and likely to the pathologic expression of the prosurvival and proangiogenic signal transducer, hypoxia-inducible factor (HIF)-1, and the reduced mitochondrial antioxidant manganese superoxide dismutase (MnSOD). In this article, we review the phenotypic changes of the endothelium in PAH and the biochemical mechanisms accounting for the proliferative, glycolytic, and strongly proangiogenic phenotype of these dysfunctional cells, which consequently foster the panvascular progressive pulmonary remodeling in PAH. © 2011 American Physiological Society.

  19. 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.

  20. Long-term feeding of red algae (Gelidium amansii ameliorates glucose and lipid metabolism in a high fructose diet-impaired glucose tolerance rat model

    Directory of Open Access Journals (Sweden)

    Hshuan-Chen Liu

    2017-07-01

    Full Text Available This study was designed to investigate the effect of Gelidium amansii (GA on carbohydrate and lipid metabolism in rats with high fructose (HF diet (57.1% w/w. Five-week-old male Sprague-Dawley rats were fed a HF diet to induce glucose intolerance and hyperlipidemia. The experiment was divided into three groups: (1 control diet group (Con; (2 HF diet group (HF; and (3 HF with GA diet group (HF + 5% GA. The rats were fed the experimental diets and drinking water ad libitum for 23 weeks. The results showed that GA significantly decreased retroperitoneal fat mass weight of HF diet-fed rats. Supplementation of GA caused a decrease in plasma glucose, insulin, tumor necrosis factor-α, and leptin. HF diet increased hepatic lipid content. However, intake of GA reduced the accumulation of hepatic lipids including total cholesterol (TC and triglyceride contents. GA elevated the excretion of fecal lipids and bile acid in HF diet-fed rats. Furthermore, GA significantly decreased plasma TC, triglyceride, low density lipoprotein plus very low density lipoprotein cholesterol, and TC/high density lipoprotein cholesterol ratio in HF diet-fed rats. HF diet induced an in plasma glucose and an impaired glucose tolerance, but GA supplementation decreased homeostasis model assessment equation-insulin resistance and improved impairment of glucose tolerance. Taken together, these results indicate that supplementation of GA can improve the impairment of glucose and lipid metabolism in an HF diet-fed rat model.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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...

  6. 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

  7. 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

  8. Glucose metabolism transporters and epilepsy: only GLUT1 has an established role.

    Science.gov (United States)

    Hildebrand, Michael S; Damiano, John A; Mullen, Saul A; Bellows, Susannah T; Oliver, Karen L; Dahl, Hans-Henrik M; Scheffer, Ingrid E; Berkovic, Samuel F

    2014-02-01

    The availability of glucose, and its glycolytic product lactate, for cerebral energy metabolism is regulated by specific brain transporters. Inadequate energy delivery leads to neurologic impairment. Haploinsufficiency of the glucose transporter GLUT1 causes a characteristic early onset encephalopathy, and has recently emerged as an important cause of a variety of childhood or later-onset generalized epilepsies and paroxysmal exercise-induced dyskinesia. We explored whether mutations in the genes encoding the other major glucose (GLUT3) or lactate (MCT1/2/3/4) transporters involved in cerebral energy metabolism also cause generalized epilepsies. A cohort of 119 cases with myoclonic astatic epilepsy or early onset absence epilepsy was screened for nucleotide variants in these five candidate genes. No epilepsy-causing mutations were identified, indicating that of the major energetic fuel transporters in the brain, only GLUT1 is clearly associated with generalized epilepsy. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.

  9. 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.

  10. Impaired glucose tolerance, type 2 diabetes and metabolic syndrome in polycystic ovary syndrome: a systematic review and meta-analysis.

    Science.gov (United States)

    Moran, Lisa J; Misso, Marie L; Wild, Robert A; Norman, Robert J

    2010-01-01

    BACKGROUND Polycystic ovary syndrome (PCOS) is a common condition in reproductive-aged women associated with impaired glucose tolerance (IGT), type 2 diabetes mellitus (DM2) and the metabolic syndrome. METHODS A literature search was conducted (MEDLINE, CINAHL, EMBASE, clinical trial registries and hand-searching) identifying studies reporting prevalence or incidence of IGT, DM2 or metabolic syndrome in women with and without PCOS. Data were presented as odds ratio (OR) [95% confidence interval (CI)] with fixed- and random-effects meta-analysis by Mantel-Haenszel methods. Quality testing was based on Newcastle-Ottawa Scaling and The Cochrane Collaboration's risk of bias assessment tool. Literature searching, data abstraction and quality appraisal were performed by two investigators. RESULTS A total of 2192 studies were reviewed and 35 were selected for final analysis. Women with PCOS had increased prevalence of IGT (OR 2.48, 95% CI 1.63, 3.77; BMI-matched studies OR 2.54, 95% CI 1.44, 4.47), DM2 (OR 4.43, 95% CI 4.06, 4.82; BMI-matched studies OR 4.00, 95% CI 1.97, 8.10) and metabolic syndrome (OR 2.88, 95% CI 2.40, 3.45; BMI-matched studies OR 2.20, 95% CI 1.36, 3.56). One study assessed IGT/DM2 incidence and reported no significant differences in DM2 incidence (OR 2.07, 95% CI 0.68, 6.30). One study assessed conversion from normal glucose tolerance to IGT/DM2 (OR 2.4, 95% CI 0.7, 8.0). No studies reported metabolic syndrome incidence. CONCLUSIONS Women with PCOS had an elevated prevalence of IGT, DM2 and metabolic syndrome in both BMI and non-BMI-matched studies. Few studies have determined IGT/DM2 or metabolic syndrome incidence in women with and without PCOS and further research is required.

  11. 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

  12. 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.

  13. Lifetime risk of developing impaired glucose metabolism and eventual progression from prediabetes to type 2 diabetes: a prospective cohort study.

    Science.gov (United States)

    Ligthart, Symen; van Herpt, Thijs T W; Leening, Maarten J G; Kavousi, Maryam; Hofman, Albert; Stricker, Bruno H C; van Hoek, Mandy; Sijbrands, Eric J G; Franco, Oscar H; Dehghan, Abbas

    2016-01-01

    Data are scarce for the lifetime risk of developing impaired glucose metabolism, including prediabetes, as are data for the risk of eventual progression from prediabetes to diabetes and for initiation of insulin treatment in previously untreated patients with diabetes. We aimed to calculate the lifetime risk of the full range of glucose impairments, from normoglycaemia to prediabetes, type 2 diabetes, and eventual insulin use. In this prospective population-based cohort analysis, we used data from the population-based Rotterdam Study. We identified diagnostic events by use of general practitioners' records, hospital discharge letters, pharmacy dispensing data, and serum fasting glucose measurements taken at the study centre (Rotterdam, Netherlands) visits. Normoglycaemia, prediabetes, and diabetes were defined on the basis of WHO criteria for fasting glucose (normoglycaemia: ≤6·0 mmol/L; prediabetes: >6·0 mmol/L and prediabetes to overt diabetes and from diabetes free of insulin treatment to insulin use. Additionally, we calculated years lived with healthy glucose metabolism. We used data from 10 050 participants from the Rotterdam Study. During a follow-up of up to 14·7 years (between April 1, 1997, and Jan 1, 2012), 1148 participants developed prediabetes, 828 developed diabetes, and 237 started insulin treatment. At age 45 years, the remaining lifetime risk was 48·7% (95% CI 46·2-51·3) for prediabetes, 31·3% (29·3-33·3) for diabetes, and 9·1% (7·8-10·3) for insulin use. In individuals aged 45 years, the lifetime risk to progress from prediabetes to diabetes was 74·0% (95% CI 67·6-80·5), and 49·1% (38·2-60·0) of the individuals with overt diabetes at this age started insulin treatment. The lifetime risks attenuated with advancing age, but increased with increasing BMI and waist circumference. On average, individuals with severe obesity lived 10 fewer years without glucose impairment compared with normal-weight individuals. Impaired glucose

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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)

  17. Cancer cell metabolism and mitochondria: Nutrient plasticity for TCA cycle fueling.

    Science.gov (United States)

    Corbet, Cyril; Feron, Olivier

    2017-08-01

    Warburg's hypothesis that cancer cells take up a lot of glucose in the presence of ambient oxygen but convert pyruvate into lactate due to impaired mitochondrial function led to the misconception that cancer cells rely on glycolysis as their major source of energy. Most recent 13 C-based metabolomic studies, including in cancer patients, indicate that cancer cells may also fully oxidize glucose. In addition to glucose-derived pyruvate, lactate, fatty acids and amino acids supply substrates to the TCA cycle to sustain mitochondrial metabolism. Here, we discuss how the metabolic flexibility afforded by these multiple mitochondrial inputs allows cancer cells to adapt according to the availability of the different fuels and the microenvironmental conditions such as hypoxia and acidosis. In particular, we focused on the role of the TCA cycle in interconnecting numerous metabolic routes in order to highlight metabolic vulnerabilities that represent attractive targets for a new generation of anticancer drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Symptoms of depression in people with impaired glucose metabolism or Type 2 diabetes mellitus: The Hoorn Study.

    Science.gov (United States)

    Adriaanse, M C; Dekker, J M; Heine, R J; Snoek, F J; Beekman, A J; Stehouwer, C D; Bouter, L M; Nijpels, G; Pouwer, F

    2008-07-01

    To study the prevalence and risk factors of depressive symptoms, comparing subjects with normal glucose metabolism (NGM), impaired glucose metabolism (IGM) or Type 2 diabetes mellitus (DM2). Cross-sectional data from a population-based cohort study conducted among 550 residents (276 men and 274 women) of the Hoorn region, the Netherlands. Levels of depressive symptoms were measured using the Centre for Epidemiologic Studies Depression Scale (CES-D score > or = 16). Glucose metabolism status was determined by means of fasting and post-load glucose levels. The prevalence of depressive symptoms in men with NGM, IGM and DM2 was 7.7, 7.0 and 15.0% (P = 0.19) and for women 7.7, 23.1 and 19.7% (P women with IGM [odds ratio (OR) = 3.60, 95% confidence interval (CI) = 1.57 to 8.28] and women with DM2 (OR = 3.18, 95% CI = 1.31 to 7.74). In men, depression was not associated with IGM (OR = 0.90, 95% CI = 0.32 to 2.57) and non-significantly more common in DM2 (OR = 2.04, 95% CI = 0.75 to 5.49). Adjustment for cardiovascular risk factors, cardiovascular disease and diabetes symptoms reduced the strength of these associations. Depressive symptoms are more common in women with IGM, but not men. Adjustment for cardiovascular risk factors, cardiovascular disease and diabetes symptoms partially attenuated these associations, suggesting that these variables could be intermediate factors.

  19. 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.

  20. Measuring body composition and energy expenditure in children with severe neurologic impairment and intellectual disability

    NARCIS (Netherlands)

    Rieken, Rob; van Goudoever, Johannes B.; Schierbeek, Henk; Willemsen, Sten P.; Calis, Elsbeth A. C.; Tibboel, Dick; Evenhuis, Heleen M.; Penning, Corine

    2011-01-01

    Accurate prediction equations for estimating body composition and total energy expenditure (TEE) in children with severe neurologic impairment and intellectual disability are currently lacking. The objective was to develop group-specific equations to predict body composition by using

  1. 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.

  2. 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.

  3. Long-term feeding of red algae (Gelidium amansii) ameliorates glucose and lipid metabolism in a high fructose diet-impaired glucose tolerance rat model.

    Science.gov (United States)

    Liu, Hshuan-Chen; Chang, Chun-Ju; Yang, Tsung-Han; Chiang, Meng-Tsan

    2017-07-01

    This study was designed to investigate the effect of Gelidium amansii (GA) on carbohydrate and lipid metabolism in rats with high fructose (HF) diet (57.1% w/w). Five-week-old male Sprague-Dawley rats were fed a HF diet to induce glucose intolerance and hyperlipidemia. The experiment was divided into three groups: (1) control diet group (Con); (2) HF diet group (HF); and (3) HF with GA diet group (HF + 5% GA). The rats were fed the experimental diets and drinking water ad libitum for 23 weeks. The results showed that GA significantly decreased retroperitoneal fat mass weight of HF diet-fed rats. Supplementation of GA caused a decrease in plasma glucose, insulin, tumor necrosis factor-α, and leptin. HF diet increased hepatic lipid content. However, intake of GA reduced the accumulation of hepatic lipids including total cholesterol (TC) and triglyceride contents. GA elevated the excretion of fecal lipids and bile acid in HF diet-fed rats. Furthermore, GA significantly decreased plasma TC, triglyceride, low density lipoprotein plus very low density lipoprotein cholesterol, and TC/high density lipoprotein cholesterol ratio in HF diet-fed rats. HF diet induced an in plasma glucose and an impaired glucose tolerance, but GA supplementation decreased homeostasis model assessment equation-insulin resistance and improved impairment of glucose tolerance. Taken together, these results indicate that supplementation of GA can improve the impairment of glucose and lipid metabolism in an HF diet-fed rat model. Copyright © 2016. Published by Elsevier B.V.

  4. Rewiring monocyte glucose metabolism via C-type lectin signaling protects against disseminated candidiasis.

    Science.gov (United States)

    Domínguez-Andrés, Jorge; Arts, Rob J W; Ter Horst, Rob; Gresnigt, Mark S; Smeekens, Sanne P; Ratter, Jacqueline M; Lachmandas, Ekta; Boutens, Lily; van de Veerdonk, Frank L; Joosten, Leo A B; Notebaart, Richard A; Ardavín, Carlos; Netea, Mihai G

    2017-09-01

    Monocytes are innate immune cells that play a pivotal role in antifungal immunity, but little is known regarding the cellular metabolic events that regulate their function during infection. Using complementary transcriptomic and immunological studies in human primary monocytes, we show that activation of monocytes by Candida albicans yeast and hyphae was accompanied by metabolic rewiring induced through C-type lectin-signaling pathways. We describe that the innate immune responses against Candida yeast are energy-demanding processes that lead to the mobilization of intracellular metabolite pools and require induction of glucose metabolism, oxidative phosphorylation and glutaminolysis, while responses to hyphae primarily rely on glycolysis. Experimental models of systemic candidiasis models validated a central role for glucose metabolism in anti-Candida immunity, as the impairment of glycolysis led to increased susceptibility in mice. Collectively, these data highlight the importance of understanding the complex network of metabolic responses triggered during infections, and unveil new potential targets for therapeutic approaches against fungal diseases.

  5. 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

  6. 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.

  7. Role of Hypothalamic VGF in Energy Balance and Metabolic Adaption to Environmental Enrichment in Mice

    Science.gov (United States)

    Foglesong, Grant D.; Huang, Wei; Liu, Xianglan; Slater, Andrew M.; Siu, Jason; Yildiz, Vedat; Salton, Stephen R. J.

    2016-01-01

    Environmental enrichment (EE), a housing condition providing complex physical, social, and cognitive stimulation, leads to improved metabolic health and resistance to diet-induced obesity and cancer. One underlying mechanism is the activation of the hypothalamic-sympathoneural-adipocyte axis with hypothalamic brain-derived neurotrophic factor (BDNF) as the key mediator. VGF, a peptide precursor particularly abundant in the hypothalamus, was up-regulated by EE. Overexpressing BDNF or acute injection of BDNF protein to the hypothalamus up-regulated VGF, whereas suppressing BDNF signaling down-regulated VGF expression. Moreover, hypothalamic VGF expression was regulated by leptin, melanocortin receptor agonist, and food deprivation mostly paralleled to BDNF expression. Recombinant adeno-associated virus-mediated gene transfer of Cre recombinase to floxed VGF mice specifically decreased VGF expression in the hypothalamus. In contrast to the lean and hypermetabolic phenotype of homozygous germline VGF knockout mice, specific knockdown of hypothalamic VGF in male adult mice led to increased adiposity, decreased core body temperature, reduced energy expenditure, and impaired glucose tolerance, as well as disturbance of molecular features of brown and white adipose tissues without effects on food intake. However, VGF knockdown failed to block the EE-induced BDNF up-regulation or decrease of adiposity indicating a minor role of VGF in the hypothalamic-sympathoneural-adipocyte axis. Taken together, our results suggest hypothalamic VGF responds to environmental demands and plays an important role in energy balance and glycemic control likely acting in the melanocortin pathway downstream of BDNF. PMID:26730934

  8. 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.

  9. Combined metformin and insulin treatment reverses metabolically impaired omental adipogenesis and accumulation of 4-hydroxynonenal in obese diabetic patients

    Directory of Open Access Journals (Sweden)

    Morana Jaganjac

    2017-08-01

    action of insulin and metformin. Further studies are needed to evaluate involvement of 4-HNE in metabolically impaired abdominal adipogenesis and to confirm benefits of combined metformin-insulin therapy in T2DM patients. Keywords: Obesity, Insulin resistance, T2DM, Omental fat, Adipogenesis, 4-hydroxynonenal, Metformin, Insulin

  10. 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.

  11. 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.

  12. 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…

  13. 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.

  14. Mitochondrial metabolism in hematopoietic stem cells requires functional FOXO3

    Science.gov (United States)

    Rimmelé, Pauline; Liang, Raymond; Bigarella, Carolina L; Kocabas, Fatih; Xie, Jingjing; Serasinghe, Madhavika N; Chipuk, Jerry; Sadek, Hesham; Zhang, Cheng Cheng; Ghaffari, Saghi

    2015-01-01

    Hematopoietic stem cells (HSC) are primarily dormant but have the potential to become highly active on demand to reconstitute blood. This requires a swift metabolic switch from glycolysis to mitochondrial oxidative phosphorylation. Maintenance of low levels of reactive oxygen species (ROS), a by-product of mitochondrial metabolism, is also necessary for sustaining HSC dormancy. Little is known about mechanisms that integrate energy metabolism with hematopoietic stem cell homeostasis. Here, we identify the transcription factor FOXO3 as a new regulator of metabolic adaptation of HSC. ROS are elevated in Foxo3−/− HSC that are defective in their activity. We show that Foxo3−/− HSC are impaired in mitochondrial metabolism independent of ROS levels. These defects are associated with altered expression of mitochondrial/metabolic genes in Foxo3−/− hematopoietic stem and progenitor cells (HSPC). We further show that defects of Foxo3−/− HSC long-term repopulation activity are independent of ROS or mTOR signaling. Our results point to FOXO3 as a potential node that couples mitochondrial metabolism with HSC homeostasis. These findings have critical implications for mechanisms that promote malignant transformation and aging of blood stem and progenitor cells. PMID:26209246

  15. 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...

  16. 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

  17. 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

  18. Short-Term Treatment with Bisphenol-A Leads to Metabolic Abnormalities in Adult Male Mice

    Science.gov (United States)

    Batista, Thiago M.; Alonso-Magdalena, Paloma; Vieira, Elaine; Amaral, Maria Esmeria C.; Cederroth, Christopher R.; Nef, Serge; Quesada, Ivan; Carneiro, Everardo M.; Nadal, Angel

    2012-01-01

    Bisphenol-A (BPA) is one of the most widespread endocrine disrupting chemicals (EDC) used as the base compound in the manufacture of polycarbonate plastics. Although evidence points to consider exposure to BPA as a risk factor for insulin resistance, its actions on whole body metabolism and on insulin-sensitive tissues are still unclear. The aim of the present work was to study the effects of low doses of BPA in insulin-sensitive peripheral tissues and whole body metabolism in adult mice. Adult mice were treated with subcutaneous injection of 100 µg/kg BPA or vehicle for 8 days. Whole body energy homeostasis was assessed with in vivo indirect calorimetry. Insulin signaling assays were conducted by western blot analysis. Mice treated with BPA were insulin resistant and had increased glucose-stimulated insulin release. BPA-treated mice had decreased food intake, lower body temperature and locomotor activity compared to control. In skeletal muscle, insulin-stimulated tyrosine phosphorylation of the insulin receptor β subunit was impaired in BPA-treated mice. This impairment was associated with a reduced insulin-stimulated Akt phosphorylation in the Thr308 residue. Both skeletal muscle and liver displayed an upregulation of IRS-1 protein by BPA. The mitogen-activated protein kinase (MAPK) signaling pathway was also impaired in the skeletal muscle from BPA-treated mice. In the liver, BPA effects were of lesser intensity with decreased insulin-stimulated tyrosine phosphorylation of the insulin receptor β subunit. In conclusion, short-term treatment with low doses of BPA slows down whole body energy metabolism and disrupts insulin signaling in peripheral tissues. Thus, our findings support the notion that BPA can be considered a risk factor for the development of type 2 diabetes. PMID:22470480

  19. Diabetes mellitus and impairment of intestinal barier function

    OpenAIRE

    Hoffmanová, Iva

    2015-01-01

    Introduction: Impairment of intestinal barrier function is involved in pathogenesis of immune mediated diseases (such as type 1 diabetes mellitus or celiac disease) and metabolic diseases (such as type 2 diabetes mellitus). Aims of study: The first aim was to analyze impairment of mucosal part of intestinal barrier in both type of diabetes and to describe differences when compared to celiac disease, which is a typical condition associated with impairment of intestinal barrier function. The se...

  20. 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

  1. Biotin deprivation impairs mitochondrial structure and function and has implications for inherited metabolic disorders.

    Science.gov (United States)

    Ochoa-Ruiz, Estefanía; Díaz-Ruiz, Rodrigo; Hernández-Vázquez, Alaín de J; Ibarra-González, Isabel; Ortiz-Plata, Alma; Rembao, Daniel; Ortega-Cuéllar, Daniel; Viollet, Benoit; Uribe-Carvajal, Salvador; Corella, José Ahmed; Velázquez-Arellano, Antonio

    2015-11-01

    Certain inborn errors of metabolism result from deficiencies in biotin containing enzymes. These disorders are mimicked by dietary absence or insufficiency of biotin, ATP deficit being a major effect,whose responsible mechanisms have not been thoroughly studied. Here we show that in rats and cultured cells it is the result of reduced TCA cycle flow, partly due to deficient anaplerotic biotin-dependent pyruvate carboxylase. This is accompanied by diminished flow through the electron transport chain, augmented by deficient cytochrome c oxidase (complex IV) activity with decreased cytochromes and reduced oxidative phosphorylation. There was also severe mitochondrial damage accompanied by decrease of mitochondria, associated with toxic levels of propionyl CoA as shown by carnitine supplementation studies, which explains the apparently paradoxical mitochondrial diminution in the face of the energy sensor AMPK activation, known to induce mitochondria biogenesis. This idea was supported by experiments on AMPK knockout mouse embryonic fibroblasts (MEFs). The multifactorial ATP deficit also provides a plausible basis for the cardiomyopathy in patients with propionic acidemia, and other diseases.Additionally, systemic inflammation concomitant to the toxic state might explain our findings of enhanced IL-6, STAT3 and HIF-1α, associated with an increase of mitophagic BNIP3 and PINK proteins, which may further increase mitophagy. Together our results imply core mechanisms of energy deficit in several inherited metabolic disorders.

  2. Interaction of pathogens with host cholesterol metabolism.

    Science.gov (United States)

    Sviridov, Dmitri; Bukrinsky, Michael

    2014-10-01

    Pathogens of different taxa, from prions to protozoa, target cellular cholesterol metabolism to advance their own development and to impair host immune responses, but also causing metabolic complications, for example, atherosclerosis. This review describes recent findings of how pathogens do it. A common theme in interaction between pathogens and host cholesterol metabolism is pathogens targeting lipid rafts of the host plasma membrane. Many intracellular pathogens use rafts as an entry gate, taking advantage of the endocytic machinery and high abundance of outward-looking molecules that can be used as receptors. At the same time, disruption of the rafts' functional capacity, achieved by the pathogens through a number of various means, impairs the ability of the host to generate immune response, thus helping pathogen to thrive. Pathogens cannot synthesize cholesterol, and salvaging host cholesterol helps pathogens build advanced cholesterol-containing membranes and assembly platforms. Impact on cholesterol metabolism is not limited to the infected cells; proteins and microRNAs secreted by infected cells affect lipid metabolism systemically. Given an essential role that host cholesterol metabolism plays in pathogen development, targeting this interaction may be a viable strategy to fight infections, as well as metabolic complications of the infections.

  3. 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...

  4. Insulin Sensitivity and Glucose Homeostasis Can Be Influenced by Metabolic Acid Load

    Directory of Open Access Journals (Sweden)

    Lucio Della Guardia

    2018-05-01

    Full Text Available Recent epidemiological findings suggest that high levels of dietary acid load can affect insulin sensitivity and glucose metabolism. Consumption of high protein diets results in the over-production of metabolic acids which has been associated with the development of chronic metabolic disturbances. Mild metabolic acidosis has been shown to impair peripheral insulin action and several epidemiological findings suggest that metabolic acid load markers are associated with insulin resistance and impaired glycemic control through an interference intracellular insulin signaling pathways and translocation. In addition, higher incidence of diabetes, insulin resistance, or impaired glucose control have been found in subjects with elevated metabolic acid load markers. Hence, lowering dietary acid load may be relevant for improving glucose homeostasis and prevention of type 2 diabetes development on a long-term basis. However, limitations related to patient acid load estimation, nutritional determinants, and metabolic status considerably flaws available findings, and the lack of solid data on the background physiopathology contributes to the questionability of results. Furthermore, evidence from interventional studies is very limited and the trials carried out report no beneficial results following alkali supplementation. Available literature suggests that poor acid load control may contribute to impaired insulin sensitivity and glucose homeostasis, but it is not sufficiently supportive to fully elucidate the issue and additional well-designed studies are clearly needed.

  5. A Controlled Trial of CPAP Therapy on Metabolic Control in Individuals with Impaired Glucose Tolerance and Sleep Apnea

    Science.gov (United States)

    Weinstock, Tanya G.; Wang, Xuelei; Rueschman, Michael; Ismail-Beigi, Faramarz; Aylor, Joan; Babineau, Denise C.; Mehra, Reena; Redline, Susan

    2012-01-01

    Study Objectives: To address whether treatment of sleep apnea improves glucose tolerance. Design: Randomized, double-blind crossover study. Setting: Sleep clinic referrals. Patients: 50 subjects with moderate to severe sleep apnea (AHI > 15) and impaired glucose tolerance. Interventions: Subjects were randomized to 8 weeks of CPAP or sham CPAP, followed by the alternate therapy after a one-month washout. After each treatment, subjects underwent 2-hour OGTT, polysomnography, actigraphy, and measurements of indices of glucose control. Measurements and Results: The primary outcome was normalization of the mean 2-h OGTT; a secondary outcome was improvement in the Insulin Sensitivity Index (ISI (0,120). Subjects were 42% men, mean age of 54 (10), BMI of 39 (8), and AHI of 44 (27). Baseline fasting glucose was 104 (12), and mean 2-h OGTT was 110 (57) mg/dL. Seven subjects normalized their mean 2-h OGTT after CPAP but not after sham CPAP, while 5 subjects normalized after sham CPAP but not after CPAP. Overall, there was no improvement in ISI (0,120) between CPAP and sham CPAP (3.6%; 95% CI: [-2.2%, 9.7%]; P = 0.22). However, in those subjects with baseline AHI ≥ 30 (n = 25), there was a 13.3% (95% CI: [5.2%, 22.1%]; P CPAP compared to sham CPAP. Conclusions: This study did not show that IGT normalizes after CPAP in subjects with moderate sleep apnea and obesity. However, insulin sensitivity improved in those with AHI ≥ 30, suggesting beneficial metabolic effects of CPAP in severe sleep apnea. Clinical Trials Information: ClinicalTrials.gov Identifier: NCT01385995. Citation: Weinstock TG; Wang X; Rueschman M; Ismail-Beigi F; Aylor J; Babineau DC; Mehra R; Redline S. A controlled trial of CPAP therapy on metabolic control in individuals with impaired glucose tolerance and sleep apnea. SLEEP 2012;35(5):617-625. PMID:22547887

  6. 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

  7. Hyperthyroidism causes cardiac dysfunction by mitochondrial impairment and energy depletion.

    Science.gov (United States)

    Maity, Sangeeta; Kar, Dipak; De, Kakali; Chander, Vivek; Bandyopadhyay, Arun

    2013-05-01

    This study elucidates the role of metabolic remodeling in cardiac dysfunction induced by hyperthyroidism. Cardiac hypertrophy, structural remodeling, and expression of the genes associated with fatty acid metabolism were examined in rats treated with triiodothyronine (T3) alone (8 μg/100 g body weight (BW), i.p.) for 15 days or along with a peroxisome proliferator-activated receptor alpha agonist bezafibrate (Bzf; 30 μg/100 g BW, oral) and were found to improve in the Bzf co-treated condition. Ultrastructure of mitochondria was damaged in T3-treated rat heart, which was prevented by Bzf co-administration. Hyperthyroidism-induced oxidative stress, reduction in cytochrome c oxidase activity, and myocardial ATP concentration were also significantly checked by Bzf. Heart function studied at different time points during the course of T3 treatment shows an initial improvement and then a gradual but progressive decline with time, which is prevented by Bzf co-treatment. In summary, the results demonstrate that hyperthyroidism inflicts structural and functional damage to mitochondria, leading to energy depletion and cardiac dysfunction.

  8. Glucose metabolism, gray matter structure, and memory decline in subjective memory impairment.

    Science.gov (United States)

    Scheef, Lukas; Spottke, Annika; Daerr, Moritz; Joe, Alexius; Striepens, Nadine; Kölsch, Heike; Popp, Julius; Daamen, Marcel; Gorris, Dominik; Heneka, Michael T; Boecker, Henning; Biersack, Hans J; Maier, Wolfgang; Schild, Hans H; Wagner, Michael; Jessen, Frank

    2012-09-25

    To identify biological evidence for Alzheimer disease (AD) in individuals with subjective memory impairment (SMI) and unimpaired cognitive performance and to investigate the longitudinal cognitive course in these subjects. [¹⁸F]fluoro-2-deoxyglucose PET (FDG-PET) and structural MRI were acquired in 31 subjects with SMI and 56 controls. Cognitive follow-up testing was performed (average follow-up time: 35 months). Differences in baseline brain imaging data and in memory decline were assessed between both groups. Associations of memory decline with brain imaging data were tested. The SMI group showed hypometabolism in the right precuneus and hypermetabolism in the right medial temporal lobe. Gray matter volume was reduced in the right hippocampus in the SMI group. At follow-up, subjects with SMI showed a poorer performance than controls on measures of episodic memory. Longitudinal memory decline in the SMI group was associated with reduced glucose metabolism in the right precuneus at baseline. The cross-sectional difference in 2 independent neuroimaging modalities indicates early AD pathology in SMI. The poorer memory performance at follow-up and the association of reduced longitudinal memory performance with hypometabolism in the precuneus at baseline support the concept of SMI as the earliest manifestation of AD.

  9. Cognitive functions in middle aged individuals are related to metabolic disturbances and aerobic capacity

    DEFF Research Database (Denmark)

    Pedersen, Maria; Pedersen, Karin Kaereby; Bruunsgaard, Helle

    2012-01-01

    Metabolic disturbances may contribute to cognitive dysfunction in patients with type 2 diabetes. We investigated the relation between cognitive impairment and metabolic deteriorations, low physical fitness, low-grade inflammation and abdominal obesity in middle aged individuals.......Metabolic disturbances may contribute to cognitive dysfunction in patients with type 2 diabetes. We investigated the relation between cognitive impairment and metabolic deteriorations, low physical fitness, low-grade inflammation and abdominal obesity in middle aged individuals....

  10. 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.

  11. Rescue of Metabolic Alterations in AR113Q Skeletal Muscle by Peripheral Androgen Receptor Gene Silencing

    Directory of Open Access Journals (Sweden)

    Elisa Giorgetti

    2016-09-01

    Full Text Available Spinal and bulbar muscular atrophy (SBMA, a progressive degenerative disorder, is caused by a CAG/glutamine expansion in the androgen receptor (polyQ AR. Recent studies demonstrate that skeletal muscle is an important site of toxicity that contributes to the SBMA phenotype. Here, we sought to identify critical pathways altered in muscle that underlie disease manifestations in AR113Q mice. This led to the unanticipated identification of gene expression changes affecting regulators of carbohydrate metabolism, similar to those triggered by denervation. AR113Q muscle exhibits diminished glycolysis, altered mitochondria, and an impaired response to exercise. Strikingly, the expression of genes regulating muscle energy metabolism is rescued following peripheral polyQ AR gene silencing by antisense oligonucleotides (ASO, a therapeutic strategy that alleviates disease. Our data establish the occurrence of a metabolic imbalance in SBMA muscle triggered by peripheral expression of the polyQ AR and indicate that alterations in energy utilization contribute to non-neuronal disease manifestations.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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...

  17. Low doses of alcohol substantially decrease glucose metabolism in the human brain.

    Science.gov (United States)

    Volkow, Nora D; Wang, Gene-Jack; Franceschi, Dinko; Fowler, Joanna S; Thanos, Panayotis Peter K; Maynard, Laurence; Gatley, S John; Wong, Christopher; Veech, Richard L; Kunos, George; Kai Li, Ting

    2006-01-01

    Moderate doses of alcohol decrease glucose metabolism in the human brain, which has been interpreted to reflect alcohol-induced decreases in brain activity. Here, we measure the effects of two relatively low doses of alcohol (0.25 g/kg and 0.5 g/kg, or 5 to 10 mM in total body H2O) on glucose metabolism in the human brain. Twenty healthy control subjects were tested using positron emission tomography (PET) and FDG after placebo and after acute oral administration of either 0.25 g/kg, or 0.5 g/kg of alcohol, administered over 40 min. Both doses of alcohol significantly decreased whole-brain glucose metabolism (10% and 23% respectively). The responses differed between doses; whereas the 0.25 g/kg dose predominantly reduced metabolism in cortical regions, the 0.5 g/kg dose reduced metabolism in cortical as well as subcortical regions (i.e. cerebellum, mesencephalon, basal ganglia and thalamus). These doses of alcohol did not significantly change the scores in cognitive performance, which contrasts with our previous results showing that a 13% reduction in brain metabolism by lorazepam was associated with significant impairment in performance on the same battery of cognitive tests. This seemingly paradoxical finding raises the possibility that the large brain metabolic decrements during alcohol intoxication could reflect a shift in the substrate for energy utilization, particularly in light of new evidence that blood-borne acetate, which is markedly increased during intoxication, is a substrate for energy production by the brain.

  18. Insulin resistance possible risk factor for cognitive impairment in fibromialgic patients.

    Science.gov (United States)

    Fava, Antonietta; Plastino, Massimiliano; Cristiano, Dario; Spanò, Antonio; Cristofaro, Stefano; Opipari, Carlo; Chillà, Antonio; Casalinuovo, Fatima; Colica, Carmen; De Bartolo, Matteo; Pirritano, Domenico; Bosco, Domenico

    2013-12-01

    To evaluate glucose metabolism and/or insulin resistance (IR) in 96 patients with Fibromyalgia (FM), associated or not to cognitive impairment. We investigated glucose metabolism in 96 FM patients. Enrolled patients were divided into two groups: 48 patients with memory deficit (group A) and 48 without memory deficit (control group). We evaluated glucose and insulin levels after a 2 h-Oral-Glucose-Tolerance-Test (2 h-OGTT) and insulin resistance (IR) by the homeostasis model assessment formula (HOMA). Body Mass Index (BMI), waist-to-hip-ratio (WHR), anxiety level, fasting plasma insulin and Non-Steroidal Anti-Inflammatory agents use were higher in patients with FM with memory impairment; while age, sex, waist circumference, education level, fasting plasma glucose, glycate hemoglobin, triglycerides, blood lipid profile, C- Reactivity-Protein (CRP), blood pressure and smoking habits were similar in both groups. Following OGTT the prevalence of glucose metabolism abnormalities was significantly higher in group A. IR was present in 79% patients, of whom 23% had also impaired glucose tolerance, 4% newly diagnosed diabetes mellitus and 52% IR only. Obesity and overweight prevailed in group A. IR, but not BMI or WHR was associated to an increased risk of memory impairment (OR = 2,6; 95% CI: 1,22-3,7). The results of this study suggest that IR may represent a risk factor for memory impairment in fibromialgic patients.

  19. 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.

  20. Impairment in visual cognition in patients with Parkinson disease

    International Nuclear Information System (INIS)

    Hirayama, Kazumi; Ishioka, Toshiyuki

    2007-01-01

    Neural pathway for visual information processing involves retina, lateral geniculate body, primary visual cortex, and higher visual cortical areas, all of which have been reported to be disordered either functionally or pathologically in Parkinson disease (PD). As elementary visual disorders, there have been studies that reported reduced contrast sensitivity for middle to high spatial frequencies and impaired blue color perception. Most of those studies suggested retina as the damaged cite that is responsible for the impairments, whereas some studies pointed to the possible cortical involvement. Impairments of higher visual functions also have been reported. In the dorsal stream, impairments of object localization, depth perception, and mental rotation have been reported. In the ventral stream, object perception and visual integration of objects have been found to be impaired. A meta-analysis study, however, concluded that although there may be impairments in higher order functions like attention and problem solving capacity there is no firm evidence for the impairments of higher visual functions. Neuroimaging studies have found a relationship between reduced metabolism centered in the parietal lobe and impaired performance in higher visual functions. Impaired identification of overlapping figures has been reported in dementia with Lewy bodies a disease that is akin to PD. Capacity to discriminate textured areas has been found to be damaged in PD. We conducted a fluorodeoxyglucose-positron emission tomography (FDG-PET) study to explore the relationship between brain metabolism and perception of overlapping figures, perception of shapes defined by texture differences and perception of subjective contours in PD. It revealed that there is a correlation between reduced activation in lateral occipital complex and impaired performance for these tasks, suggesting some compromised ventral rout functions. (author)

  1. 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

  2. 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.

  3. Toxic metabolic syndrome associated with HAART

    DEFF Research Database (Denmark)

    Haugaard, Steen B

    2006-01-01

    (HAART) may encounter the HIV-associated lipodystrophy syndrome (HALS), which attenuates patient compliance to this treatment. HALS is characterised by impaired glucose and lipid metabolism and other risk factors for cardiovascular disease. This review depicts the metabolic abnormalities associated...... with HAART by describing the key cell and organ systems that are involved, emphasising the role of insulin resistance. An opinion on the remedies available to treat the metabolic abnormalities and phenotype of HALS is provided....

  4. 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.

  5. 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

  6. 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

  7. Effects of Aerobic Training on Cognition and Brain Glucose Metabolism in Subjects with Mild Cognitive Impairment.

    Science.gov (United States)

    Porto, Fábio Henrique de Gobbi; Coutinho, Artur Martins Novaes; Pinto, Ana Lucia de Sá; Gualano, Bruno; Duran, Fabio Luís de Souza; Prando, Silvana; Ono, Carla Rachel; Spíndola, Lívia; de Oliveira, Maira Okada; do Vale, Patrícia Helena Figuerêdo; Nitrini, Ricardo; Buchpiguel, Carlos Alberto; Brucki, Sonia Maria Dozzi

    2015-01-01

    Aerobic training (AT) is a promising intervention for mild cognitive impairment (MCI). To evaluate the effects of AT on cognition and regional brain glucose metabolism (rBGM) in MCI patients. Subjects performed a twice-a-week, moderate intensity, AT program for 24 weeks. Assessment with ADAS-cog, a comprehensive neuropsychological battery, and evaluation of rBGM with positron emission tomography with 18F-fluorodeoxyglucose ([18F]FDG-PET) were performed before and after the intervention. Aerobic capacity was compared using the maximal oxygen consumption VO2max (mL/Kg/min). [18F]FDG-PET data were analyzed on a voxel-by-voxel basis with SPM8 software. Forty subjects were included, with a mean (M) age of 70.3 (5.4) years and an initial Mini-Mental State Exam score of 27.4 (1.7). Comparisons using paired t-tests revealed improvements in the ADAS-cog (M difference: -2.7 (3.7), p <  0.001) and VO2max scores (M difference: 1.8 (2.0) mL/kg/min, p <  0.001). Brain metabolic analysis revealed a bilateral decrease in the rBGM of the dorsal anterior cingulate cortex, pFWE = 0.04. This rBGM decrease was negatively correlated with improvement in a visuospatial function/attentional test (rho =-0.31, p = 0.04). Several other brain areas also showed increases or decreases in rBGM. Of note, there was an increase in the retrosplenial cortex, an important node of the default mode network, that was negatively correlated with the metabolic decrease in the dorsal anterior cingulate cortex (r =-0.51, p = 0.001). AT improved cognition and changed rBGM in areas related to cognition in subjects with MCI.

  8. Persistent increase in oxygen consumption and impaired neurovascular coupling after spreading depression in rat neocortex.

    Science.gov (United States)

    Piilgaard, Henning; Lauritzen, Martin

    2009-09-01

    Cortical spreading depression (CSD) is associated with a dramatic failure of brain ion homeostasis and increased energy metabolism. There is strong clinical and experimental evidence to suggest that CSD is the mechanism of migraine, and involved in progressive neuronal injury in stroke and head trauma. Here we tested the hypothesis that single episodes of CSD induced acute hypoxia, and prolonged impairment of neurovascular and neurometabolic coupling. Cortical spreading depression was induced in rat frontal cortex, whereas cortical electrical activity and local field potentials (LFPs) were recorded by glass microelectrodes, cerebral blood flow (CBF) by laser-Doppler flowmetry, and tissue oxygen tension (tpO(2)) with polarographic microelectrodes. Cortical spreading depression increased cerebral metabolic rate of oxygen (CMRO(2)) by 71%+/-6.7% and CBF by 238%+/-48.1% for 1 to 2 mins. For the following 2 h, basal tpO(2) and CBF were reduced whereas basal CMRO(2) was persistently elevated by 8.1%+/-2.9%. In addition, within first hour after CSD we found impaired neurovascular coupling (LFP versus CBF), whereas neurometabolic coupling (LFP versus CMRO(2)) remained unaffected. Impaired neurovascular coupling was explained by both reduced vascular reactivity and suppressed function of cortical inhibitory interneurons. The protracted effects of CSD on basal CMRO(2) and neurovascular coupling may contribute to cellular dysfunction in patients with migraine and acutely injured cerebral cortex.

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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

    2015-04-07

    Metabolic homeostasis is regulated by the brain, but 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 in 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 lipid levels. Importantly, this function of metabolic learning requires not only the mushroom body but also 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 that 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 that the brain, and potentially the hypothalamus, direct metabolic learning and the formation of memories, which contribute to the control of systemic metabolic homeostasis.

  17. [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.

  18. 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...

  19. Protein energy malnutrition associates with different types of hearing impairments in toddlers: Anemia increases cochlear dysfunction.

    Science.gov (United States)

    Kamel, Terez Boshra; Deraz, Tharwat Ezzat; Elkabarity, Rasha H; Ahmed, Rasha K

    2016-06-01

    This work aimed to highlight a challenging asymptomatic problem which is early detection of hearing impairment in toddlers with protein energy malnutrition (PEM) as a neuro-cognitive effect of PEM on developing brain in relation to hemoglobin level. 100 toddlers, aged 6-24 months, fifty with moderate/severe PEM and fifty healthy children, were included in study. Both TEOAEs and ABR testing were used to assess auditory function. Study reported an association between malnutrition and hearing impairment, 26% of cases had conductive deafness secondary to otitis media with effusion using tympanometry; 84.6% showed type B and 15.4% type C which may suggest developing or resolving otitis media. Their ABR showed 46% mild and 53% moderate impairment. 32% of PEM cases had sensory neural hearing loss and with type (A) tympanometry. Those were assessed using ABR; 58% had mild, 34% moderate and 8% profound impairment. 10% of PEM cases had mixed hearing loss with 50% type B and 50% type C tympanometry and their ABR showed moderate to profound impairment. TEOAEs latencies at different frequencies correlate negatively with hemoglobin level. Toddlers with moderate/severe PEM had hearing impairments of different types and degrees. Neuro-physiological methods could be early and safe detectors of auditory disorders especially in high-risk toddlers. Anemia increases risk for auditory dysfunction. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Peculiarities of Ischemic Heart Disease Course and Treatment in Patients with Glucose Metabolism Impairment and Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    O.M. Radchenko

    2015-09-01

    chosen taking into account their impact on glucose metabolism with avoidance of drugs and treatment schemes, which lead to its impairment; usage of well-targeted drugs with clear indications as there is a lasting need for large number of drugs with unpredictable interactions.

  2. Lipopolysaccharide-induced brain activation of the indoleamine 2,3-dioxygenase and depressive-like behavior are impaired in a mouse model of metabolic syndrome.

    Science.gov (United States)

    Dinel, Anne-Laure; André, Caroline; Aubert, Agnès; Ferreira, Guillaume; Layé, Sophie; Castanon, Nathalie

    2014-02-01

    Although peripheral low-grade inflammation has been associated with a high incidence of mood symptoms in patients with metabolic syndrome (MetS), much less is known about the potential involvement of brain activation of cytokines in that context. Recently we showed in a mouse model of MetS, namely the db/db mice, an enhanced hippocampal inflammation associated with increased anxiety-like behavior (Dinel et al., 2011). However, depressive-like behavior was not affected in db/db mice. Based on the strong association between depressive-like behavior and cytokine-induced brain activation of indoleamine 2,3-dioxygenase (IDO), the enzyme that metabolizes tryptophan along the kynurenine pathway, these results may suggest an impairment of brain IDO activation in db/db mice. To test this hypothesis, we measured the ability of db/db mice and their healthy db/+ littermates to enhance brain IDO activity and depressive-like behavior after a systemic immune challenge with lipopolysaccharide (LPS). Here we show that LPS (5 μg/mouse) significantly increased depressive-like behavior (increased immobility time in a forced-swim test, FST) 24h after treatment in db/+ mice, but not in db/db mice. Interestingly, db/db mice also displayed after LPS treatment blunted increase of brain kynurenine/tryptophan ratio compared to their db/+ counterparts, despite enhanced induction of hippocampal cytokine expression (interleukin-1β, tumor necrosis factor-α). Moreover, this was associated with an impaired effect of LPS on hippocampal expression of the brain-derived neurotrophic factor (BDNF) that contributes to mood regulation, including under inflammatory conditions. Collectively, these data indicate that the rise in brain tryptophan catabolism and depressive-like behavior induced by innate immune system activation is impaired in db/db mice. These findings could have relevance in improving the management and treatment of inflammation-related complications in MetS. Copyright © 2013 Elsevier

  3. 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.

  4. Intermittent fasting protects against the deterioration of cognitive function, energy metabolism and dyslipidemia in Alzheimer's disease-induced estrogen deficient rats.

    Science.gov (United States)

    Shin, Bae Kun; Kang, Suna; Kim, Da Sol; Park, Sunmin

    2018-02-01

    , cortisol levels were increased by Alzheimer's disease but decreased by intermittent fasting. Intermittent fasting improved dyslipidemia and liver damage index compared to ad libitum. Alzheimer's disease lowered low-density lipoprotein cholesterol and serum triglyceride levels compared to Non-Alzheimer's disease. In conclusion, Alzheimer's disease impaired not only cognitive function but also disturbed energy, glucose, lipid, and bone metabolism in ovariectomized rats. Intermittent fasting protected against the deterioration of these metabolic parameters, but it exacerbated bone mineral density loss and insulin resistance at fasting in Alzheimer's disease-induced estrogen-deficient rats. Impact statement Intermittent fasting was evaluated for its effects on cognitive function and metabolic disturbances in a rat model of menopause and Alzheimer's disease. Intermittent fasting decreased skin temperature and fat mass, and improved glucose tolerance with decreasing food intake. Intermittent fasting also prevented memory loss: short-term and special memory loss. Therefore, intermittent fasting may prevent some of the metabolic pathologies associated with menopause and protect against age-related memory decline.

  5. 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

  6. 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.

  7. 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.

  8. Intrauterine growth retarded progeny of pregnant sows fed high protein:low carbohydrate diet is related to metabolic energy deficit.

    Directory of Open Access Journals (Sweden)

    Cornelia C Metges

    Full Text Available High and low protein diets fed to pregnant adolescent sows led to intrauterine growth retardation (IUGR. To explore underlying mechanisms, sow plasma metabolite and hormone concentrations were analyzed during different pregnancy stages and correlated with litter weight (LW at birth, sow body weight and back fat thickness. Sows were fed diets with low (6.5%, LP, adequate (12.1%, AP, and high (30%, HP protein levels, made isoenergetic by adjusted carbohydrate content. At -5, 24, 66, and 108 days post coitum (dpc fasted blood was collected. At 92 dpc, diurnal metabolic profiles were determined. Fasted serum urea and plasma glucagon were higher due to the HP diet. High density lipoprotein cholesterol (HDLC, %HDLC and cortisol were reduced in HP compared with AP sows. Lowest concentrations were observed for serum urea and protein, plasma insulin-like growth factor-I, low density lipoprotein cholesterol, and progesterone in LP compared with AP and HP sows. Fasted plasma glucose, insulin and leptin concentrations were unchanged. Diurnal metabolic profiles showed lower glucose in HP sows whereas non-esterified fatty acids (NEFA concentrations were higher in HP compared with AP and LP sows. In HP and LP sows, urea concentrations were 300% and 60% of AP sows, respectively. Plasma total cholesterol was higher in LP than in AP and HP sows. In AP sows, LW correlated positively with insulin and insulin/glucose and negatively with glucagon/insulin at 66 dpc, whereas in HP sows LW associated positively with NEFA. In conclusion, IUGR in sows fed high protein:low carbohydrate diet was probably due to glucose and energy deficit whereas in sows with low protein:high carbohydrate diet it was possibly a response to a deficit of indispensable amino acids which impaired lipoprotein metabolism and favored maternal lipid disposal.

  9. 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.

  10. Astrocytic Pathological Calcium Homeostasis and Impaired Vesicle Trafficking in Neurodegeneration

    Directory of Open Access Journals (Sweden)

    Nina Vardjan

    2017-02-01

    Full Text Available Although the central nervous system (CNS consists of highly heterogeneous populations of neurones and glial cells, clustered into diverse anatomical regions with specific functions, there are some conditions, including alertness, awareness and attention that require simultaneous, coordinated and spatially homogeneous activity within a large area of the brain. During such events, the brain, representing only about two percent of body mass, but consuming one fifth of body glucose at rest, needs additional energy to be produced. How simultaneous energy procurement in a relatively extended area of the brain takes place is poorly understood. This mechanism is likely to be impaired in neurodegeneration, for example in Alzheimer’s disease, the hallmark of which is brain hypometabolism. Astrocytes, the main neural cell type producing and storing glycogen, a form of energy in the brain, also hold the key to metabolic and homeostatic support in the central nervous system and are impaired in neurodegeneration, contributing to the slow decline of excitation-energy coupling in the brain. Many mechanisms are affected, including cell-to-cell signalling. An important question is how changes in cellular signalling, a process taking place in a rather short time domain, contribute to the neurodegeneration that develops over decades. In this review we focus initially on the slow dynamics of Alzheimer’s disease, and on the activity of locus coeruleus, a brainstem nucleus involved in arousal. Subsequently, we overview much faster processes of vesicle traffic and cytosolic calcium dynamics, both of which shape the signalling landscape of astrocyte-neurone communication in health and neurodegeneration.

  11. Obesity-driven gut microbiota inflammatory pathways to metabolic syndrome

    Directory of Open Access Journals (Sweden)

    Luiz Henrique Agra eCavalcante-Silva

    2015-11-01

    Full Text Available The intimate interplay between immune system, metabolism and gut microbiota plays an important role in controlling metabolic homeostasis and possible obesity development. Obesity involves impairment of immune response affecting both innate and adaptive immunity. The main factors involved in the relationship of obesity with inflammation have not been completely elucidated. On the other hand, gut microbiota, via innate immune receptors, has emerged as one of the key factors regulating events triggering acute inflammation associated with obesity and metabolic syndrome. Inflammatory disorders lead to several signalling transduction pathways activation, inflammatory cytokine, chemokine production and cell migration, which in turn cause metabolic dysfunction. Inflamed adipose tissue, with increased macrophages infiltration, is associated with impaired preadipocyte development and differentiation to mature adipose cells, leading to ectopic lipid accumulation and insulin resistance. This review focuses on the relationship between obesity and inflammation, which is essential to understand the pathological mechanisms governing metabolic syndrome.

  12. 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

  13. Diet-induced obesity, energy metabolism and gut microbiota in C57BL/6J mice fed Western diets based on lean seafood or lean meat mixtures.

    Science.gov (United States)

    Holm, Jacob Bak; Rønnevik, Alexander; Tastesen, Hanne Sørup; Fjære, Even; Fauske, Kristin Røen; Liisberg, Ulrike; Madsen, Lise; Kristiansen, Karsten; Liaset, Bjørn

    2016-05-01

    High protein diets may protect against diet-induced obesity, but little is known regarding the effects of different protein sources consumed at standard levels. We investigated how a mixture of lean seafood or lean meat in a Western background diet modulated diet-induced obesity, energy metabolism and gut microbiota. Male C57BL/6J mice fed a Western diet (WD) containing a mixture of lean seafood (seafood WD) for 12weeks accumulated less fat mass than mice fed a WD containing a mixture of lean meat (meat WD). Meat WD-fed mice exhibited increased fasting blood glucose, impaired glucose clearance, elevated fasting plasma insulin and increased plasma and liver lipid levels. We observed no first choice preference for either of the WDs, but over time, mice fed the seafood WD consumed less energy than mice fed the meat WD. Mice fed the seafood WD exhibited higher spontaneous locomotor activity and a lower respiratory exchange ratio (RER) than mice fed the meat WD. Thus, higher activity together with the decreased energy intake contributed to the different phenotypes observed in mice fed the seafood WD compared to mice fed the meat WD. Comparison of the gut microbiomes of mice fed the two WDs revealed significant differences in the relative abundance of operational taxonomic units (OTUs) belonging to the orders Bacteroidales and Clostridiales, with genes involved in metabolism of aromatic amino acids exhibiting higher relative abundance in the microbiomes of mice fed the seafood WD. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. Intranasal Insulin Therapy for Cognitive Impairment and Neurodegeneration: Current State of the Art

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    de la Monte, Suzanne M.

    2015-01-01

    Introduction Growing evidence supports the concept that insulin resistance plays an important role in the pathogenesis of cognitive impairment and neurodegeneration, including in Alzheimer's disease (AD). The metabolic hypothesis has led to the development and utilization of insulin- and insulin agonist-based treatments. Therapeutic challenges faced include the ability to provide effective treatments that do not require repeated injections and also minimize potentially hazardous off-target effects. Areas covered This review covers the role of intra-nasal insulin therapy for cognitive impairment and neurodegeneration, particularly Alzheimer's disease. The literature reviewed focuses on data published within the past 5 years as this field is evolving rapidly. The author provides evidence that brain insulin resistance is an important and early abnormality in Alzheimer's disease, and that increasing brain supply and utilization of insulin improves cognition and memory. Emphasis was placed on discussing outcomes of clinical trials and interpreting discordant results to clarify the benefits and limitations of intranasal insulin therapy. Expert Opinion Intranasal insulin therapy can efficiently and directly target the brain to support energy metabolism, myelin maintenance, cell survival, and neuronal plasticity, which begin to fail in the early stages of neurodegeneration. Efforts must continue toward increasing the safety, efficacy, and specificity of intranasal insulin therapy. PMID:24215447

  19. 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

  20. 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.

  1. High passage MIN6 cells have impaired insulin secretion with impaired glucose and lipid oxidation.

    Directory of Open Access Journals (Sweden)

    Kim Cheng

    Full Text Available Type 2 diabetes is a metabolic disorder characterized by the inability of beta-cells to secrete enough insulin to maintain glucose homeostasis. MIN6 cells secrete insulin in response to glucose and other secretagogues, but high passage (HP MIN6 cells lose their ability to secrete insulin in response to glucose. We hypothesized that metabolism of glucose and lipids were defective in HP MIN6 cells causing impaired glucose stimulated insulin secretion (GSIS. HP MIN6 cells had no first phase and impaired second phase GSIS indicative of global functional impairment. This was coupled with a markedly reduced ATP content at basal and glucose stimulated states. Glucose uptake and oxidation were higher at basal glucose but ATP content failed to increase with glucose. HP MIN6 cells had decreased basal lipid oxidation. This was accompanied by reduced expressions of Glut1, Gck, Pfk, Srebp1c, Ucp2, Sirt3, Nampt. MIN6 cells represent an important model of beta cells which, as passage numbers increased lost first phase but retained partial second phase GSIS, similar to patients early in type 2 diabetes onset. We believe a number of gene expression changes occurred to produce this defect, with emphasis on Sirt3 and Nampt, two genes that have been implicated in maintenance of glucose homeostasis.

  2. 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

  3. 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.

  4. 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.

  5. Cerebral Glucose Metabolism and Sedation in Brain-injured Patients: A Microdialysis Study.

    Science.gov (United States)

    Hertle, Daniel N; Santos, Edgar; Hagenston, Anna M; Jungk, Christine; Haux, Daniel; Unterberg, Andreas W; Sakowitz, Oliver W

    2015-07-01

    Disturbed brain metabolism is a signature of primary damage and/or precipitates secondary injury processes after severe brain injury. Sedatives and analgesics target electrophysiological functioning and are as such well-known modulators of brain energy metabolism. Still unclear, however, is how sedatives impact glucose metabolism and whether they differentially influence brain metabolism in normally active, healthy brain and critically impaired, injured brain. We therefore examined and compared the effects of anesthetic drugs under both critical (1 mmol/L) extracellular brain glucose levels. We performed an explorative, retrospective analysis of anesthetic drug administration and brain glucose concentrations, obtained by bedside microdialysis, in 19 brain-injured patients. Our investigations revealed an inverse linear correlation between brain glucose and both the concentration of extracellular glutamate (Pearson r=-0.58, P=0.01) and the lactate/glucose ratio (Pearson r=-0.55, P=0.01). For noncritical brain glucose levels, we observed a positive linear correlation between midazolam dose and brain glucose (Pbrain glucose levels, extracellular brain glucose was unaffected by any type of sedative. These findings suggest that the use of anesthetic drugs may be of limited value in attempts to influence brain glucose metabolism in injured brain tissue.

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

    Directory of Open Access Journals (Sweden)

    Duo Zhang

    2016-07-01

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

  7. Metabolic reprogramming in the tumour microenvironment: a hallmark shared by cancer cells and T lymphocytes.

    Science.gov (United States)

    Allison, Katrina E; Coomber, Brenda L; Bridle, Byram W

    2017-10-01

    Altered metabolism is a hallmark of cancers, including shifting oxidative phosphorylation to glycolysis and up-regulating glutaminolysis to divert carbon sources into biosynthetic pathways that promote proliferation and survival. Therefore, metabolic inhibitors represent promising anti-cancer drugs. However, T cells must rapidly divide and survive in harsh microenvironments to mediate anti-cancer effects. Metabolic profiles of cancer cells and activated T lymphocytes are similar, raising the risk of metabolic inhibitors impairing the immune system. Immune checkpoint blockade provides an example of how metabolism can be differentially impacted to impair cancer cells but support T cells. Implications for research with metabolic inhibitors are discussed. © 2017 John Wiley & Sons Ltd.

  8. 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.

  9. 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.

  10. 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; Nem