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Sample records for affect carbohydrate metabolism

  1. Disorders of Carbohydrate Metabolism

    MedlinePlus

    ... Metabolic Disorders Disorders of Carbohydrate Metabolism Disorders of Amino Acid Metabolism Disorders of Lipid Metabolism Carbohydrates are sugars. ... Metabolic Disorders Disorders of Carbohydrate Metabolism Disorders of Amino Acid Metabolism Disorders of Lipid Metabolism NOTE: This is ...

  2. Dietary carbohydrate and lipid source affect cholesterol metabolism of European sea bass (Dicentrarchus labrax) juveniles.

    PubMed

    Castro, Carolina; Corraze, Geneviève; Pérez-Jiménez, Amalia; Larroquet, Laurence; Cluzeaud, Marianne; Panserat, Stéphane; Oliva-Teles, Aires

    2015-10-28

    Plant feedstuffs (PF) are rich in carbohydrates, which may interact with lipid metabolism. Thus, when considering dietary replacement of fishery by-products with PF, knowledge is needed on how dietary lipid source (LS) and carbohydrates affect lipid metabolism and other metabolic pathways. For that purpose, a 73-d growth trial was performed with European sea bass juveniles (IBW 74 g) fed four diets differing in LS (fish oil (FO) or a blend of vegetable oils (VO)) and carbohydrate content (0 % (CH-) or 20 % (CH+) gelatinised starch). At the end of the trial no differences among diets were observed on growth and feed utilisation. Protein efficiency ratio was, however, higher in the CH+ groups. Muscle and liver fatty acid profiles reflected the dietary LS. Dietary carbohydrate promoted higher plasma cholesterol and phospholipids (PL), whole-body and hepatic (mainly 16 : 0) lipids and increased muscular and hepatic glycogen. Except for PL, which were higher in the FO groups, no major alterations between FO and VO groups were observed on plasma metabolites (glucose, TAG, cholesterol, PL), liver and muscle glycogen, and lipid and cholesterol contents. Activities of glucose-6-phosphate dehydrogenase and malic enzyme - lipogenesis-related enzymes - increased with carbohydrate intake. Hepatic expression of genes involved in cholesterol metabolism was up-regulated with carbohydrate (HMGCR and CYP3A27) and VO (HMGCR and CYP51A1) intake. No dietary regulation of long-chain PUFA biosynthesis at the transcriptional level was observed. Overall, very few interactions between dietary carbohydrates and LS were observed. However, important insights on the direct relation between dietary carbohydrate and the cholesterol biosynthetic pathway in European sea bass were demonstrated.

  3. Carbohydrate Metabolism Disorders

    MedlinePlus

    Metabolism is the process your body uses to make energy from the food you eat. Food is ... disorder, something goes wrong with this process. Carbohydrate metabolism disorders are a group of metabolic disorders. Normally ...

  4. Potato tuber expression of Arabidopsis WRINKLED1 increase triacylglycerol and membrane lipids while affecting central carbohydrate metabolism.

    PubMed

    Hofvander, Per; Ischebeck, Till; Turesson, Helle; Kushwaha, Sandeep K; Feussner, Ivo; Carlsson, Anders S; Andersson, Mariette

    2016-09-01

    Tuber and root crops virtually exclusively accumulate storage products in the form of carbohydrates. An exception is yellow nutsedge (Cyperus esculentus) in which tubers have the capacity to store starch and triacylglycerols (TAG) in roughly equal amounts. This suggests that a tuber crop can efficiently handle accumulation of energy dense oil. From a nutritional as well as economic aspect, it would be of interest to utilize the high yield capacity of tuber or root crops for oil accumulation similar to yellow nutsedge. The transcription factor WRINKLED1 from Arabidopsis thaliana, which in seed embryos induce fatty acid synthesis, has been shown to be a major factor for oil accumulation. WRINKLED1 was expressed in potato (Solanum tuberosum) tubers to explore whether this factor could impact tuber metabolism. This study shows that a WRINKLED1 transcription factor could induce triacylglycerol accumulation in tubers of transformed potato plants grown in field (up to 12 nmol TAG/mg dry weight, 1% of dry weight) together with a large increase in polar membrane lipids. The changes in metabolism further affected starch accumulation and composition concomitant with massive increases in sugar content.

  5. Carbohydrate metabolism in pregnancy

    PubMed Central

    Herrera, Emilo; Knopp, Robert H.; Freinkel, Norbert

    1969-01-01

    The effects of late pregnancy on metabolic fuels, liver composition, gluconeogenesis, and nitrogen metabolism have been examined in fed and fasted rats. Plasma free fatty acid (FFA) and immunoreactive insulin (IRI) are greater and glucose and ketones are lower in fed 19-day pregnant than they are in agematched virgin rats. A 48 hr fast elicits greater increases in FFA and ketones and more profound reductions in glucose in the pregnant rats and obliterates the differences in IRI. Fetal weight is not modified by such fasting but maternal weight losses exceed that of the nongravid rats. Livers from rats 19 days pregnant contain more and larger hepatocytes. Per μmole hepatic deoxyribonucleic acid (DNA)-phosphorus, water and protein are more abundant, whereas glycogen is unaffected. Livers from fed pregnant rats contain more lipid phosphorus and less neutral lipid fatty acid. After a 48 hr fast, hepatic steatosis supervenes in gravid animals due to accumulated neutral fat. The contents of hepatic acetyl-coenzyme A (CoA) and citric acid are not different in fed pregnant and virgin rats but are greater in the pregnant rats after fasting. Formation of glucose-14C and glycogen-14C from administered pyruvate-14C are the same in fed pregnant and virgin rats, but greater in the pregnant ones after a 24 or 48 hr fast. Pregnancy does not affect creatinine excretion, and urinary urea is not different in fed pregnant, virgin, and postpartum animals. Contrariwise, more nitrogen, potassium, and phosphorus are excreted by the pregnant animals during a 2 day fast. The increment in urinary nitrogen is due largely to urea on the 1st day, whereas heightened ammonia accounts for half the increase on the 2nd and correlates with the enhanced ketonuria. Muscle catabolism, gluconeogenesis, and diversion to fat are activated more rapidly and to a greater degree when food is withheld during late gestation in the rat. These catabolic propensities are restrained in the fed state. The capacity

  6. Impact of Dietary Carbohydrate and Protein Levels on Carbohydrate Metabolism

    ERIC Educational Resources Information Center

    Lasker, Denise Ann

    2009-01-01

    The goal of this dissertation was to investigate the impact of changing dietary carbohydrate (CARB) intakes within recommended dietary guidelines on metabolic outcomes specifically associated with glycemic regulations and carbohydrate metabolism. This research utilized both human and animal studies to examine changes in metabolism across a wide…

  7. Exercise and Regulation of Carbohydrate Metabolism.

    PubMed

    Mul, Joram D; Stanford, Kristin I; Hirshman, Michael F; Goodyear, Laurie J

    2015-01-01

    Carbohydrates are the preferred substrate for contracting skeletal muscles during high-intensity exercise and are also readily utilized during moderate intensity exercise. This use of carbohydrates during physical activity likely played an important role during the survival of early Homo sapiens, and genes and traits regulating physical activity, carbohydrate metabolism, and energy storage have undoubtedly been selected throughout evolution. In contrast to the life of early H. sapiens, modern lifestyles are predominantly sedentary. As a result, intake of excessive amounts of carbohydrates due to the easy and continuous accessibility to modern high-energy food and drinks has not only become unnecessary but also led to metabolic diseases in the face of physical inactivity. A resulting metabolic disease is type 2 diabetes, a complex endocrine disorder characterized by abnormally high concentrations of circulating glucose. This disease now affects millions of people worldwide. Exercise has beneficial effects to help control impaired glucose homeostasis with metabolic disease, and is a well-established tool to prevent and combat type 2 diabetes. This chapter focuses on the effects of exercise on carbohydrate metabolism in skeletal muscle and systemic glucose homeostasis. We will also focus on the molecular mechanisms that mediate the effects of exercise to increase glucose uptake in skeletal muscle. It is now well established that there are different proximal signaling pathways that mediate the effects of exercise and insulin on glucose uptake, and these distinct mechanisms are consistent with the ability of exercise to increase glucose uptake in the face of insulin resistance in people with type 2 diabetes. Ongoing research in this area is aimed at defining the precise mechanism by which exercise increases glucose uptake and insulin sensitivity and the types of exercise necessary for these important health benefits.

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

    PubMed

    Jurgoński, Adam; Juśkiewicz, Jerzy; Zduńczyk, Zenon

    2014-02-03

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

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

    PubMed Central

    Jurgoński, Adam; Juśkiewicz, Jerzy; Zduńczyk, Zenon

    2014-01-01

    The aim of this model study was to investigate how selected gut functions and serum lipid profile in rats on high-fat diets differed according to the type of fat (saturated vs. unsaturated) and carbohydrate (simple vs. complex). The experiment was conducted using 32 male Wistar rats distributed into 4 groups of 8 animals each. For 4 weeks, the animals were fed group-specific diets that were either rich in lard or soybean oil (16% of the diet) as the source of saturated or unsaturated fatty acids, respectively; further, each lard- and soybean oil-rich diet contained either fructose or corn starch (45.3% of the diet) as the source of simple or complex carbohydrates, respectively. Both dietary factors contributed to changes in the caecal short-chain fatty acid concentrations, especially to the butyrate concentration, which was higher in rats fed lard- and corn starch-rich diets compared to soybean oil- and fructose-rich diets, respectively. The lowest butyrate concentration was observed in rats fed the soybean oil- and fructose-rich diet. On the other hand, the lard- and fructose-rich diet vs. the other dietary combinations significantly increased serum total cholesterol concentration, to more than two times serum triglyceride concentration and to more than five times the atherogenic index. In conclusion, a high-fat diet rich in fructose can unfavorably affect gut metabolism when unsaturated fats are predominant in the diet or the blood lipids when a diet is rich in saturated fats. PMID:24496299

  10. Varying forage type, metabolizable protein concentration, and carbohydrate source affects manure excretion, manure ammonia, and nitrogen metabolism of dairy cows.

    PubMed

    Weiss, W P; Willett, L B; St-Pierre, N R; Borger, D C; McKelvey, T R; Wyatt, D J

    2009-11-01

    Effects of forage source, concentration of metabolizable protein (MP), and type of carbohydrate on manure excretion by dairy cows and production of ammonia from that manure were evaluated using a central composite experimental design. All diets (dry basis) contained 50% forage that ranged from 25:75 to 75:25 alfalfa silage:corn silage. Diets contained 10.7% rumen-degradable protein with variable concentrations of undegradable protein so that dietary MP ranged from 8.8 to 12%. Starch concentration ranged from 22 to 30% with a concomitant decrease in neutral detergent fiber. A total of 15 diets were fed to 36 Holstein cows grouped in 6 blocks. Each block was a replicated 3 x 3 Latin square resulting in 108 observations. Manure output (urine and feces) was measured using total collection, and fresh feces and urine were combined into slurries and incubated for 48 h to measure NH3-N production. Feces, urine, and manure output averaged 50.5, 29.5, and 80.1 kg/d, respectively. Manure output increased with increasing dry matter intake (approximately 3.5 kg of manure/kg of dry matter intake), increased concentrations of alfalfa (mostly via changes in urine output), and decreased concentrations of starch (mostly via changes in fecal output). The amount of NH3-N produced per gram of manure decreased with increasing alfalfa because excreted N shifted from urine to feces. Increasing MP increased NH3-N produced per gram of manure mainly because of increased urinary N, but increased fecal N also contributed to the manure NH3. Manure NH3-N production per cow (accounts for effects on manure production and NH3-N produced per unit of manure) was least and milk protein yields were maximal for diets with high alfalfa (75% of the forage), moderate MP (11% of diet dry matter), and high starch (30% of diet dry matter).

  11. The Effects of Breakfast Consumption and Composition on Metabolic Wellness with a Focus on Carbohydrate Metabolism.

    PubMed

    Maki, Kevin C; Phillips-Eakley, Alyssa K; Smith, Kristen N

    2016-05-01

    Findings from epidemiologic studies indicate that there are associations between breakfast consumption and a lower risk of type 2 diabetes mellitus (T2DM) and metabolic syndrome, prompting interest in the influence of breakfast on carbohydrate metabolism and indicators of T2DM risk. The objective of this review was to summarize the available evidence from randomized controlled trials assessing the impact of breakfast on variables related to carbohydrate metabolism and metabolic wellness. Consuming compared with skipping breakfast appeared to improve glucose and insulin responses throughout the day. Breakfast composition may also be important. Dietary patterns high in rapidly available carbohydrate were associated with elevated T2DM risk. Therefore, partial replacement of rapidly available carbohydrate with other dietary components, such as whole grains and cereal fibers, proteins, and unsaturated fatty acids (UFAs), at breakfast may be a useful strategy for producing favorable metabolic outcomes. Consumption of fermentable and viscous dietary fibers at breakfast lowers glycemia and insulinemia. Fermentable fibers likely act through enhancing insulin sensitivity later in the day, and viscous fibers have an acute effect to slow the rate of carbohydrate absorption. Partially substituting protein for rapidly available carbohydrate enhances satiety and diet-induced thermogenesis, and also favorably affects lipoprotein lipids and blood pressure. Partially substituting UFA for carbohydrate has been associated with improved insulin sensitivity, lipoprotein lipids, and blood pressure. Overall, the available evidence suggests that consuming breakfast foods high in whole grains and cereal fiber, while limiting rapidly available carbohydrate, is a promising strategy for metabolic health promotion.

  12. Isolation of carbohydrate-metabolizing, extremely halophilic bacteria.

    NASA Technical Reports Server (NTRS)

    Tomlinson, G. A.; Hochstein, L. I.

    1972-01-01

    Four previously unrecognized strains of extremely halophilic bacteria that utilize carbohydrates have been isolated. Gas production proved an unreliable index of carbohydrate metabolism; therefore, carbohydrate utilization was measured by determining acid formation and sugar disappearance during growth. By these procedures, carbohydrate utilization was readily detected. The results suggest that carbohydrate dissimilation by extremely halophilic bacteria may be more common than previously thought and that the apparent rarity of carbohydrate-metabolizing halophiles may be an artifact of the isolation procedures used.

  13. Hearing Loss, Dizziness, and Carbohydrate Metabolism

    PubMed Central

    Albernaz, Pedro L. Mangabeira

    2015-01-01

    Introduction  Metabolic activity of the inner ear is very intense, and makes it sensitive to changes in the body homeostasis. This study involves a group of patients with inner ear disorders related to carbohydrate metabolism disturbances, including hearing loss, tinnitus, dizziness, and episodes of vertigo. Objectives  To describe the symptoms of metabolic inner ear disorders and the examinations required to establish diagnoses. These symptoms are often the first to allow for an early diagnosis of metabolic disorders and diabetes. Methods  Retrospective study of 376 patients with inner ear symptoms suggestive of disturbances of carbohydrate metabolism. The authors present patientś clinical symptoms and clinical evaluations, with emphasis on the glucose and insulin essays. Results  Authors based their conclusions on otolaryngological findings, diagnostic procedures and treatment principles. They found that auditory and vestibular symptoms usually occur prior to other manifestations of metabolic changes, leading to an early diagnosis of hyperinsulinemia, intestinal sugar malabsorption or diabetes. Previously undiagnosed diabetes mellitus type II was found in 39 patients. Conclusions  The identification of carbohydrate metabolism disturbances is important not only to minimize the patients' clinical symptoms, but also to help maintain their general health. PMID:27413410

  14. Carbohydrate Metabolism in Bifidobacteria: Human Symbiotic Bacteria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bifidobacterium ssp. constitute up to 90% of microbial gut flora in the infant colon, but considerably less in adults. Carbohydrate metabolism in these bacteria is highly unusual. Data from four Bifidobacterium genomes indicates genes missing from glycolysis, gluconeogenesis, and the TCA cycle, in...

  15. A quick look at biochemistry: carbohydrate metabolism.

    PubMed

    Dashty, Monireh

    2013-10-01

    In mammals, there are different metabolic pathways in cells that break down fuel molecules to transfer their energy into high energy compounds such as adenosine-5'-triphosphate (ATP), guanosine-5'-triphosphate (GTP), reduced nicotinamide adenine dinucleotide (NADH2), reduced flavin adenine dinucleotide (FADH2) and reduced nicotinamide adenine dinucleotide phosphate (NADPH2). This process is called cellular respiration. In carbohydrate metabolism, the breakdown starts from digestion of food in the gastrointestinal tract and is followed by absorption of carbohydrate components by the enterocytes in the form of monosaccharides. Monosaccharides are transferred to cells for aerobic and anaerobic respiration via glycolysis, citric acid cycle and pentose phosphate pathway to be used in the starvation state. In the normal state, the skeletal muscle and liver cells store monosaccharides in the form of glycogen. In the obesity state, the extra glucose is converted to triglycerides via lipogenesis and is stored in the lipid droplets of adipocytes. In the lipotoxicity state, the lipid droplets of other tissues such as the liver, skeletal muscle and pancreatic beta cells also accumulate triacylglycerol. This event is the axis of the pathogenesis of metabolic dysregulation in insulin resistance, metabolic syndrome and type 2 diabetes. In this paper a summary of the metabolism of carbohydrates is presented in a way that researchers can follow the biochemical processes easily.

  16. Acclimatory responses of the Daphnia pulex proteome to environmental changes. I. Chronic exposure to hypoxia affects the oxygen transport system and carbohydrate metabolism

    PubMed Central

    Zeis, Bettina; Lamkemeyer, Tobias; Paul, Rüdiger J; Nunes, Frank; Schwerin, Susanne; Koch, Marita; Schütz, Wolfgang; Madlung, Johannes; Fladerer, Claudia; Pirow, Ralph

    2009-01-01

    Background Freshwater planktonic crustaceans of the genus Daphnia show a remarkable plasticity to cope with environmental changes in oxygen concentration and temperature. One of the key proteins of adaptive gene control in Daphnia pulex under hypoxia is hemoglobin (Hb), which increases in hemolymph concentration by an order of magnitude and shows an enhanced oxygen affinity due to changes in subunit composition. To explore the full spectrum of adaptive protein expression in response to low-oxygen conditions, two-dimensional gel electrophoresis and mass spectrometry were used to analyze the proteome composition of animals acclimated to normoxia (oxygen partial pressure [Po2]: 20 kPa) and hypoxia (Po2: 3 kPa), respectively. Results The comparative proteome analysis showed an up-regulation of more than 50 protein spots under hypoxia. Identification of a major share of these spots revealed acclimatory changes for Hb, glycolytic enzymes (enolase), and enzymes involved in the degradation of storage and structural carbohydrates (e.g. cellubiohydrolase). Proteolytic enzymes remained constitutively expressed on a high level. Conclusion Acclimatory adjustments of the D. pulex proteome to hypoxia included a strong induction of Hb and carbohydrate-degrading enzymes. The scenario of adaptive protein expression under environmental hypoxia can be interpreted as a process to improve oxygen transport and carbohydrate provision for the maintenance of ATP production, even during short episodes of tissue hypoxia requiring support from anaerobic metabolism. PMID:19383146

  17. Consumption of caffeinated coffee and a high carbohydrate meal affects postprandial metabolism of a subsequent oral glucose tolerance test in young, healthy males.

    PubMed

    Moisey, Lesley L; Robinson, Lindsay E; Graham, Terry E

    2010-03-01

    Caffeine and caffeinated coffee (CC) elicit acute insulin insensitivity when ingested before a carbohydrate load. The effects of CC on glucose tolerance and insulin sensitivity when co-ingested with a high carbohydrate meal and on postprandial metabolism of a subsequent (second) carbohydrate load have not been studied. In a randomised, crossover design, ten healthy males ingested either CC (5 mg caffeine/kg body weight), decaffeinated coffee (DC) or water (W; equal volume) co-ingested with a high glycaemic index cereal followed 3 h later by a 75 g oral glucose tolerance test. After the initial meal, insulin area under the curve (AUC) and insulin sensitivity index did not differ between treatments, although glucose AUC for CC (107 (sem 18) mmol/l x 3 h) and DC (74 (sem 15) mmol/l x 3 h) was greater than W ( - 0.2 (sem 29) mmol/l x 3 h, P < 0.05). After the second carbohydrate load, insulin AUC for CC was 49 % and 57 % greater (P < 0.01) than for DC and W, respectively. Despite the greater insulin response, glucose AUC for CC (217 (sem 24) mmol/l x 2 h) was greater than both DC (126 (sem 11) mmol/l x 2 h, P = 0.01) and W (55 (sem 34) mmol/l x 2 h, P < 0.001). Insulin sensitivity index after the second meal was lower after CC (8.2 (sem 0.9)) compared with both DC (12.4 (sem 1.2), P < 0.01) and W (13.4 (sem 1.4), P < 0.001). Co-ingestion of CC with one meal resulted in insulin insensitivity during the postprandial phase of a second meal in the absence of further CC ingestion. Thus, CC may play a role in daily glycaemic management.

  18. Metabolic aspects of low carbohydrate diets and exercise

    PubMed Central

    Peters, Sandra J; LeBlanc, Paul J

    2004-01-01

    Following a low carbohydrate diet, there is a shift towards more fat and less carbohydrate oxidation to provide energy to skeletal muscle, both at rest and during exercise. This review summarizes recent work on human skeletal muscle carbohydrate and fat metabolic adaptations to a low carbohydrate diet, focusing mainly on pyruvate dehydrogenase and pyruvate dehydrogenase kinase, and how these changes relate to the capacity for carbohydrate oxidation during exercise. PMID:15507161

  19. Genome of Bifidobacteria and Carbohydrate Metabolism

    PubMed Central

    2015-01-01

    In recent years, the knowledge about bifidobacteria has considerably evolved thanks to recent progress in molecular biology. The analysis of the whole genome sequences of 48 taxa of bifidobacteria offers new perspectives for their classification, especially to set up limit between two species. Indeed, several species are presenting a high homology and should be reclassified. On the other hand, some subspecies are presenting a low homology and should therefore be reclassified into different species. In addition, a better knowledge of the genome of bifidobacteria allows a better understanding of the mechanisms involved in complex carbohydrate metabolism. The genome of some species of bifidobacteria from human but also from animal origin demonstrates high presence in genes involved in the metabolism of complex oligosaccharides. Those species should be further tested to confirm their potential to metabolize complex oligosaccharides in vitro and in vivo. PMID:26761794

  20. Loss of Cytosolic Phosphoglucose Isomerase Affects Carbohydrate Metabolism in Leaves and Is Essential for Fertility of Arabidopsis1[C][W][OPEN

    PubMed Central

    Kunz, Hans-Henning; Zamani-Nour, Shirin; Häusler, Rainer E.; Ludewig, Katja; Schroeder, Julian I.; Malinova, Irina; Fettke, Joerg; Flügge, Ulf-Ingo; Gierth, Markus

    2014-01-01

    Carbohydrate metabolism in plants is tightly linked to photosynthesis and is essential for energy and carbon skeleton supply of the entire organism. Thus, the hexose phosphate pools of the cytosol and the chloroplast represent important metabolic resources that are maintained through action of phosphoglucose isomerase (PGI) and phosphoglucose mutase interconverting glucose 6-phosphate, fructose 6-phosphate, and glucose 1-phosphate. Here, we investigated the impact of disrupted cytosolic PGI (cPGI) function on plant viability and metabolism. Overexpressing an artificial microRNA targeted against cPGI (amiR-cpgi) resulted in adult plants with vegetative tissue essentially free of cPGI activity. These plants displayed diminished growth compared with the wild type and accumulated excess starch in chloroplasts but maintained low sucrose content in leaves at the end of the night. Moreover, amiR-cpgi plants exhibited increased nonphotochemical chlorophyll a quenching during photosynthesis. In contrast to amiR-cpgi plants, viable transfer DNA insertion mutants disrupted in cPGI function could only be identified as heterozygous individuals. However, homozygous transfer DNA insertion mutants could be isolated among plants ectopically expressing cPGI. Intriguingly, these plants were only fertile when expression was driven by the ubiquitin10 promoter but sterile when the seed-specific unknown seed protein promoter or the Cauliflower mosaic virus 35S promoter were employed. These data show that metabolism is apparently able to compensate for missing cPGI activity in adult amiR-cpgi plants and indicate an essential function for cPGI in plant reproduction. Moreover, our data suggest a feedback regulation in amiR-cpgi plants that fine-tunes cytosolic sucrose metabolism with plastidic starch turnover. PMID:25104722

  1. Pill formulations and their effect on lipid and carbohydrate metabolism.

    PubMed

    Brooks, P G

    1984-07-01

    Recent data on oral contraceptives (OCs) employing new low-dose formulations appear to indicate that most of the previously reported metabolic effects are minimized, particularly when a product is neigher ovverly estrogenic nor progestational. Evidence suggests that elevated levels of cholesterol and triglycerides in the plasma are correlated with the risk of cardiovascular disease. Epidemiologic students have indicated a correlation between elevation of low denisty lipoprotein (LDL) cholesterol and coronary heart disease, and a correlation between decreases in high density lipoprotein (HDL) cholesterol and arterial disease. Epidemiologic evidence seems to suggest that combination OCs are associated with increased cardiovascular risk, especially risks of venous thrombosis, myocardial infarction, and stroke. There is some debate as to whether OCs themselves are an independent risk factor or whether they increase the effects of other risk factors. Women using combination OCs have been reported to have higher total serum triglyceride and cholesterol concentrations, related primarily to the estrogen dose. While most of the earlier literature associated estrogens with a higher risk of cardiovascular disease, recent studies have increasingly implicated the progestin component. Increasing potencies of progestin have been found to proportionally lower the HDL-cholesterol level. There is a positive association between the estrogen dose and HDL-cholesterol level. Among combination pill users, HDL levels gevverally depend on the relative amounts and potencies of both components. It is generally agreed that there are some high-risk women who should be carefully monitored while using the pill or who should not use it at all. Steroid type and dosage both play a role in affecting carbohydrate metabolism. Ethinyl estradiol (EE), the estrogen component in most OCs, does not seem to have the same biphasic effect on carbohydrate metaolism as most other estrogens. Most of the recent

  2. Carbohydrate and the regulation of blood glucose and metabolism.

    PubMed

    Wolever, Thomas M S

    2003-05-01

    Classifying the glycemic responses of carbohydrate foods using the glycemic index (GI) requires standardized methodology for valid results. Dietary carbohydrates influence metabolism by at least four mechanisms: nature of the monosaccharides absorbed, amount of carbohydrate consumed, rate of absorption, and colonic fermentation. Reducing glycemic responses by reducing carbohydrate intake increases postprandial serum free-fatty acids (FFA) and does not improve overall glycemic control in diabetic subjects. By contrast, low-GI diets reduce serum FFA and improve glycemic control. Thus, current evidence supports FAO/WHO recommendations to maintain a high-carbohydrate diet and choose low-GI starchy foods.

  3. Metabolic response to high-carbohydrate and low-carbohydrate meals in a nonhuman primate model

    PubMed Central

    Fabbrini, Elisa; Higgins, Paul B.; Magkos, Faidon; Bastarrachea, Raul A.; Voruganti, V. Saroja; Comuzzie, Anthony G.; Shade, Robert E.; Gastaldelli, Amalia; Horton, Jay D.; Omodei, Daniela; Patterson, Bruce W.

    2013-01-01

    We established a model of chronic portal vein catheterization in an awake nonhuman primate to provide a comprehensive evaluation of the metabolic response to low-carbohydrate/high-fat (LCHF; 20% carbohydrate and 65% fat) and high-carbohydrate/low-fat (HCLF; 65% carbohydrate and 20% fat) meal ingestion. Each meal was given 1 wk apart to five young adult (7.8 ± 1.3 yr old) male baboons. A [U-13C]glucose tracer was added to the meal, and a [6,6-2H2]glucose tracer was infused systemically to assess glucose kinetics. Plasma areas under the curve (AUCs) of glucose, insulin, and C-peptide in the femoral artery and of glucose and insulin in the portal vein were higher (P ≤ 0.05) after ingestion of the HCLF compared with the LCHF meal. Compared with the LCHF meal, the rate of appearance of ingested glucose into the portal vein and the systemic circulation was greater after the HCLF meal (P < 0.05). Endogenous glucose production decreased by ∼40% after ingestion of the HCLF meal but was not affected by the LCHF meal (P < 0.05). Portal vein blood flow increased (P < 0.001) to a similar extent after consumption of either meal. In conclusion, a LCHF diet causes minimal changes in the rate of glucose appearance in both portal and systemic circulations, does not affect the rate of endogenous glucose production, and causes minimal stimulation of C-peptide and insulin. These observations demonstrate that LCHF diets cause minimal perturbations in glucose homeostasis and pancreatic β-cell activity. PMID:23269412

  4. Abnormal Carbohydrate Metabolism in Chronic Renal Failure

    PubMed Central

    Rubenfeld, Sheldon; Garber, Alan J.

    1978-01-01

    To delineate the potential role of disordered glucose and glucose-precursor kinetics in the abnormal carbohydrate metabolism of chronic renal failure, alanine and glucose production and utilization and gluconeogenesis from alanine were studied in patients with chronic compensated renal insufficiency and in normal volunteers. With simultaneous primed injection-continuous infusions of radiolabeled alanine and glucose, rates of metabolite turnover and precursor-product interrelationships were calculated from the plateau portion of the appropriate specific activity curves. All subjects were studied in the postabsorption state. In 13 patients with chronic renal failure (creatinine = 10.7±1.2 mg/100 ml; mean±SEM), glucose turnover was found to be 1,035±99.3 μmol/min. This rate was increased 56% (P = 0.003) over that observed in control subjects (664±33.5 μmol/min). Alanine turnover was 474±96.0 μmol/min in azotemic patients. This rate was 191% greater (P = 0.007) than the rate determined in control subjects (163±19.4 μmol/min). Gluconeogenesis from alanine and the percent of glucose production contributed by gluconeogenesis from alanine were increased in patients with chronic renal failure (192% and 169%, respectively) as compared to controls (P < 0.05 for each). Alanine utilization for gluconeogenesis was increased from 40.2±3.86 μmol/min in control subjects to 143±39.0 μmol/min in azotemic patients (P < 0.05). The percent of alanine utilization accounted for by gluconeogenesis was not altered in chronic renal insufficiency. In nondiabetic azotemic subjects, mean fasting glucose and immunoreactive insulin levels were increased 24.3% (P = 0.005) and 130% (P = 0.046), respectively. These results in patients with chronic renal failure demonstrate (a) increased glucose production and utilization, (b) increased gluconeogenesis from alanine, (c) increased alanine production and utilization, and (d) a relative impairment to glucose disposal. We conclude that

  5. New insights into the interaction of carbohydrate and fat metabolism during exercise.

    PubMed

    Spriet, Lawrence L

    2014-05-01

    Fat and carbohydrate are important fuels for aerobic exercise and there can be reciprocal shifts in the proportions of carbohydrate and fat that are oxidized. The interaction between carbohydrate and fatty acid oxidation is dependent on the intracellular and extracellular metabolic environments. The availability of substrate, both from inside and outside of the muscle, and exercise intensity and duration will affect these environments. The ability of increasing fat provision to downregulate carbohydrate metabolism in the heart, diaphragm and peripheral skeletal muscle has been well studied. However, the regulation of fat metabolism in human skeletal muscle during exercise in the face of increasing carbohydrate availability and exercise intensity has not been well studied until recently. Research in the past 10 years has demonstrated that the regulation of fat metabolism is complex and involves many sites of control, including the transport of fat into the muscle cell, the binding and transport of fat in the cytoplasm, the regulation of intramuscular triacylglycerol synthesis and breakdown, and the transport of fat into the mitochondria. The discovery of proteins that assist in transporting fat across the plasma and mitochondrial membranes, the ability of these proteins to translocate to the membranes during exercise, and the new roles of adipose triglyceride lipase and hormone-sensitive lipase in regulating skeletal muscle lipolysis are examples of recent discoveries. This information has led to the proposal of mechanisms to explain the downregulation of fat metabolism that occurs in the face of increasing carbohydrate availability and when moving from moderate to intense aerobic exercise.

  6. Calystegines in potatoes with genetically engineered carbohydrate metabolism.

    PubMed

    Richter, Ute; Sonnewald, Uwe; Dräger, Birgit

    2007-01-01

    Calystegines are hydroxylated nortropane alkaloids derived from the tropane alkaloid biosynthetic pathway. They are strong glycosidase inhibitors and occur in vegetables such as potatoes, tomatoes, and cabbage. Calystegine accumulation in root cultures was described to increase with carbohydrate availability. Whether this is indicative for the in planta situation is as yet unknown. Potatoes are model plants for the study of carbohydrate metabolism. Numerous transgenic potato lines with altered carbohydrate metabolism are available, but rarely were examined for alterations in secondary metabolism. In this study, calystegine accumulation and expression of biosynthetic enzymes were related to genetic modifications in carbohydrate metabolism in potato tubers. Tubers contained more soluble sugars due to overexpression of yeast invertase in the apoplast or in the cytosol, or due to antisense suppression of sucrose synthase. It is shown that the major part of calystegines in tubers originated from biosynthesis in plant roots. Yet, tuber calystegine levels responded to genetic alterations of carbohydrate metabolism in tubers. The strongest increase in calystegines was found in tubers with suppressed sucrose synthase activity. Transcripts and enzyme activities involved in calystegine biosynthesis largely concurred with product accumulation. Whole plant organs were examined similarly and displayed higher calystegines and corresponding enzyme activities in roots and stolons of plants with enhanced soluble sugars. Increases in calystegines appear to be linked to sucrose availability.

  7. Carbohydrates

    MedlinePlus

    Starches; Simple sugars; Sugars; Complex carbohydrates; Diet - carbohydrates; Simple carbohydrates ... forms of carbohydrates to function properly. Sugars and starches are broken down by the body into glucose ( ...

  8. Transformation with TT8 and HB12 RNAi Constructs in Model Forage (Medicago sativa, Alfalfa) Affects Carbohydrate Structure and Metabolic Characteristics in Ruminant Livestock Systems.

    PubMed

    Li, Xinxin; Zhang, Yonggen; Hannoufa, Abdelali; Yu, Peiqiang

    2015-11-04

    Lignin, a phenylpropanoid polymer present in secondary cell walls, has a negative impact on feed digestibility. TT8 and HB12 genes were shown to have low expression levels in low-lignin tissues of alfalfa, but to date, there has been no study on the effect of down-regulation of these two genes in alfalfa on nutrient chemical profiles and availability in ruminant livestock systems. The objectives of this study were to investigate the effect of transformation of alfalfa with TT8 and HB12 RNAi constructs on carbohydrate (CHO) structure and CHO nutritive value in ruminant livestock systems. The results showed that transformation with TT8 and HB12 RNAi constructs reduced rumen, rapidly degraded CHO fractions (RDCA4, P = 0.06; RDCB1, P < 0.01) and totally degraded CHO fraction (TRDCHO, P = 0.08). Both HB12 and TT8 populations had significantly higher in vitro digestibility of neutral detergent fiber (NDF) at 30 h of incubation (ivNDF30) compared to the control (P < 0.01). The TT8 populations had highest ivDM30 and ivNDF240. Transformation of alfalfa with TT8 and HB12 RNAi constructs induced molecular structure changes. Different CHO functional groups had different sensitivities and different responses to the transformation. The CHO molecular structure changes induced by the transformation were associated with predicted CHO availability. Compared with HB12 RNAi, transformation with TT8 RNAi could improve forage quality by increasing the availability of both NDF and DM. Further study is needed on the relationship between the transformation-induced structure changes at a molecular level and nutrient utilization in ruminant livestock systems when lignification is much higher.

  9. Normal Roles for Dietary Fructose in Carbohydrate Metabolism

    PubMed Central

    Laughlin, Maren R.

    2014-01-01

    Although there are many well-documented metabolic effects linked to the fructose component of a very high sugar diet, a healthy diet is also likely to contain appreciable fructose, even if confined to that found in fruits and vegetables. These normal levels of fructose are metabolized in specialized pathways that synergize with glucose at several metabolic steps. Glucose potentiates fructose absorption from the gut, while fructose catalyzes glucose uptake and storage in the liver. Fructose accelerates carbohydrate oxidation after a meal. In addition, emerging evidence suggests that fructose may also play a role in the secretion of insulin and GLP-1, and in the maturation of preadipocytes to increase fat storage capacity. Therefore, fructose undergoing its normal metabolism has the interesting property of potentiating the disposal of a dietary carbohydrate load through several routes. PMID:25100436

  10. Anaplasma phagocytophilum Infection Subverts Carbohydrate Metabolic Pathways in the Tick Vector, Ixodes scapularis

    PubMed Central

    Cabezas-Cruz, Alejandro; Alberdi, Pilar; Valdés, James J.; Villar, Margarita; de la Fuente, José

    2017-01-01

    The obligate intracellular pathogen, Anaplasma phagocytophilum, is the causative agent of human, equine, and canine granulocytic anaplasmosis and tick-borne fever (TBF) in ruminants. A. phagocytophilum has become an emerging tick-borne pathogen in the United States, Europe, Africa, and Asia, with increasing numbers of infected people and animals every year. It has been recognized that intracellular pathogens manipulate host cell metabolic pathways to increase infection and transmission in both vertebrate and invertebrate hosts. However, our current knowledge on how A. phagocytophilum affect these processes in the tick vector, Ixodes scapularis is limited. In this study, a genome-wide search for components of major carbohydrate metabolic pathways was performed in I. scapularis ticks for which the genome was recently published. The enzymes involved in the seven major carbohydrate metabolic pathways glycolysis, gluconeogenesis, pentose phosphate, tricarboxylic acid cycle (TCA), glyceroneogenesis, and mitochondrial oxidative phosphorylation and β-oxidation were identified. Then, the available transcriptomics and proteomics data was used to characterize the mRNA and protein levels of I. scapularis major carbohydrate metabolic pathway components in response to A. phagocytophilum infection of tick tissues and cultured cells. The results showed that major carbohydrate metabolic pathways are conserved in ticks. A. phagocytophilum infection inhibits gluconeogenesis and mitochondrial metabolism, but increases the expression of glycolytic genes. A model was proposed to explain how A. phagocytophilum could simultaneously control tick cell glucose metabolism and cytoskeleton organization, which may be achieved in part by up-regulating and stabilizing hypoxia inducible factor 1 alpha in a hypoxia-independent manner. The present work provides a more comprehensive view of the major carbohydrate metabolic pathways involved in the response to A. phagocytophilum infection in ticks

  11. A Holistic View of Dietary Carbohydrate Utilization in Lobster: Digestion, Postprandial Nutrient Flux, and Metabolism

    PubMed Central

    Casuso, Antonio; Perdomo-Morales, Rolando; Gutierrez, Odilia; Scull, Idania; Carrillo, Olimpia; Martos-Sitcha, Juan A.; García-Galano, Tsai; Mancera, Juan Miguel

    2014-01-01

    Crustaceans exhibit a remarkable variation in their feeding habits and food type, but most knowledge on carbohydrate digestion and utilization in this group has come from research on few species. The aim of this study was to make an integrative analysis of dietary carbohydrate utilization in the spiny lobster Panulirus argus. We used complementary methodologies such as different assessments of digestibility, activity measurements of digestive and metabolic enzymes, and post-feeding flux of nutrients and metabolites. Several carbohydrates were well digested by the lobster, but maize starch was less digestible than all other starches studied, and its inclusion in diet affected protein digestibility. Most intense hydrolysis of carbohydrates in the gastric chamber of lobster occurred between 2–6 h after ingestion and afterwards free glucose increased in hemolymph. The inclusion of wheat in diet produced a slow clearance of glucose from the gastric fluid and a gradual increase in hemolymph glucose. More intense hydrolysis of protein in the gastric chamber occurred 6–12 h after ingestion and then amino acids tended to increase in hemolymph. Triglyceride concentration in hemolymph rose earlier in wheat-fed lobsters than in lobsters fed other carbohydrates, but it decreased the most 24 h later. Analyses of metabolite levels and activities of different metabolic enzymes revealed that intermolt lobsters had a low capacity to store and use glycogen, although it was slightly higher in wheat-fed lobsters. Lobsters fed maize and rice diets increased amino acid catabolism, while wheat-fed lobsters exhibited higher utilization of fatty acids. Multivariate analysis confirmed that the type of carbohydrate ingested had a profound effect on overall metabolism. Although we found no evidence of a protein-sparing effect of dietary carbohydrate, differences in the kinetics of their digestion and absorption impacted lobster metabolism determining the fate of other nutrients. PMID

  12. A holistic view of dietary carbohydrate utilization in lobster: digestion, postprandial nutrient flux, and metabolism.

    PubMed

    Rodríguez-Viera, Leandro; Perera, Erick; Casuso, Antonio; Perdomo-Morales, Rolando; Gutierrez, Odilia; Scull, Idania; Carrillo, Olimpia; Martos-Sitcha, Juan A; García-Galano, Tsai; Mancera, Juan Miguel

    2014-01-01

    Crustaceans exhibit a remarkable variation in their feeding habits and food type, but most knowledge on carbohydrate digestion and utilization in this group has come from research on few species. The aim of this study was to make an integrative analysis of dietary carbohydrate utilization in the spiny lobster Panulirus argus. We used complementary methodologies such as different assessments of digestibility, activity measurements of digestive and metabolic enzymes, and post-feeding flux of nutrients and metabolites. Several carbohydrates were well digested by the lobster, but maize starch was less digestible than all other starches studied, and its inclusion in diet affected protein digestibility. Most intense hydrolysis of carbohydrates in the gastric chamber of lobster occurred between 2-6 h after ingestion and afterwards free glucose increased in hemolymph. The inclusion of wheat in diet produced a slow clearance of glucose from the gastric fluid and a gradual increase in hemolymph glucose. More intense hydrolysis of protein in the gastric chamber occurred 6-12 h after ingestion and then amino acids tended to increase in hemolymph. Triglyceride concentration in hemolymph rose earlier in wheat-fed lobsters than in lobsters fed other carbohydrates, but it decreased the most 24 h later. Analyses of metabolite levels and activities of different metabolic enzymes revealed that intermolt lobsters had a low capacity to store and use glycogen, although it was slightly higher in wheat-fed lobsters. Lobsters fed maize and rice diets increased amino acid catabolism, while wheat-fed lobsters exhibited higher utilization of fatty acids. Multivariate analysis confirmed that the type of carbohydrate ingested had a profound effect on overall metabolism. Although we found no evidence of a protein-sparing effect of dietary carbohydrate, differences in the kinetics of their digestion and absorption impacted lobster metabolism determining the fate of other nutrients.

  13. Enhanced fermentative capacity of yeasts engineered in storage carbohydrate metabolism.

    PubMed

    Pérez-Torrado, Roberto; Matallana, Emilia

    2015-01-01

    During yeast biomass production, cells are grown through several batch and fed-batch cultures on molasses. This industrial process produces several types of stresses along the process, including thermic, osmotic, starvation, and oxidative stress. It has been shown that Saccharomyces cerevisiae strains with enhanced stress resistance present enhanced fermentative capacity of yeast biomass produced. On the other hand, storage carbohydrates have been related to several types of stress resistance in S. cerevisiae. Here we have engineered industrial strains in storage carbohydrate metabolism by overexpressing the GSY2 gene, that encodes the glycogen synthase enzyme, and deleting NTH1 gene, that encodes the neutral trehalase enzyme. Industrial biomass production process simulations were performed with control and modified strains to measure cellular carbohydrates and fermentation capacity of the produced biomass. These modifications increased glycogen and trehalose levels respectively during bench-top trials of industrial biomass propagation. We finally show that these strains display an improved fermentative capacity than its parental strain after biomass production. Modification of storage carbohydrate content increases fermentation or metabolic capacity of yeast which can be an interesting application for the food industry.

  14. Carbohydrate Content and Enzyme Metabolism in Developing Canola Siliques.

    PubMed Central

    King, S. P.; Lunn, J. E.; Furbank, R. T.

    1997-01-01

    Little biochemical information is available on carbohydrate metabolism in developing canola (Brassica napus L.) silique (pod) wall and seed tissues. This research examines the carbohydrate contents and sucrose (Suc) metabolic enzyme activities in different aged silique wall and seed tissues during oil filling. The silique wall partitioned photosynthate into Suc over starch and predominantly accumulated hexose. The silique wall hexose content and soluble acid invertase activity rapidly fell as embryos progressed from the early- to late-cotyledon developmental stages. A similar trend was not evident for alkaline invertase, Suc synthase (SuSy), and Suc-phosphate synthase. Silique wall SuSy activities were much higher than source leaves at all times and may serve to supply the substrate for secondary cell wall thickening. In young seeds starch was the predominant accumulated carbohydrate over the sampled developmental range. Seed hexose levels dropped as embryos developed from the early- to midcotyledon stage. Hexose and starch were localized to the testa or liquid endosperm, whereas Suc was evenly distributed among seed components. With the switch to oil accumulation, seed SuSy activity increased by 3.6-fold and soluble acid invertase activity decreased by 76%. These data provide valuable baseline knowledge for the genetic manipulation of canola seed carbon partitioning. PMID:12223695

  15. Carbohydrate Metabolism of Cactus in a Desert Environment

    PubMed Central

    Sutton, B. G.; Ting, Irwin P.; Sutton, R.

    1981-01-01

    The concentration of glucan, mucilage, soluble carbohydrates, and malic acid were determined in Opuntia bigelovii Engelm. during a 23-week period. The experiment began during the dry summer by irrigation to stimulate Crassulacean acid metabolism and was followed by 13 weeks of drought. After the 13-week drought period, the plants were irrigated throughout a 10-week period until late December. The maximum level of malic acid determined each day at dawn decreased throughout the drought period and increased after irrigation. High levels of malic acid occurring at dawn are indicative of active Crassulacean acid metabolism. Soluble carbohydrates also decreased during drought and increased after irrigation. Both glucan and mucilage increased slightly for about 9 weeks during the drought period and then began to decrease. Irrigation was accompanied by a further decrease in concentration of glucan and mucilage. Since both glucan and mucilage changed in a similar manner and since their concentrations in the tissue are correlated, it is hypothesized that both function as storage carbohydrates. Whereas glucan is the nocturnal substrate for malic acid synthesis, there are no data to support or refute a similar hypothesis for mucilage. PMID:16661999

  16. Carbohydrate metabolism of cactus in a desert environment.

    PubMed

    Sutton, B G

    1981-09-01

    The concentration of glucan, mucilage, soluble carbohydrates, and malic acid were determined in Opuntia bigelovii Engelm. during a 23-week period. The experiment began during the dry summer by irrigation to stimulate Crassulacean acid metabolism and was followed by 13 weeks of drought. After the 13-week drought period, the plants were irrigated throughout a 10-week period until late December. The maximum level of malic acid determined each day at dawn decreased throughout the drought period and increased after irrigation. High levels of malic acid occurring at dawn are indicative of active Crassulacean acid metabolism. Soluble carbohydrates also decreased during drought and increased after irrigation. Both glucan and mucilage increased slightly for about 9 weeks during the drought period and then began to decrease. Irrigation was accompanied by a further decrease in concentration of glucan and mucilage. Since both glucan and mucilage changed in a similar manner and since their concentrations in the tissue are correlated, it is hypothesized that both function as storage carbohydrates. Whereas glucan is the nocturnal substrate for malic acid synthesis, there are no data to support or refute a similar hypothesis for mucilage.

  17. Altered oxidative stress and carbohydrate metabolism in canine mammary tumors

    PubMed Central

    Jayasri, K.; Padmaja, K.; Saibaba, M.

    2016-01-01

    Aim: Mammary tumors are the most prevalent type of neoplasms in canines. Even though cancer induced metabolic alterations are well established, the clinical data describing the metabolic profiles of animal tumors is not available. Hence, our present investigation was carried out with the aim of studying changes in carbohydrate metabolism along with the level of oxidative stress in canine mammary tumors. Materials and Methods: Fresh mammary tumor tissues along with the adjacent healthy tissues were collected from the college surgical ward. The levels of thiobarbituric acid reactive substances (TBARS), glutathione, protein, hexose, hexokinase, glucose-6-phosphatase, fructose-1, 6-bisphosphatase, and glucose-6-phosphate dehydrogenase (G6PD) were analyzed in all the tissues. The results were analyzed statistically. Results: More than two-fold increase in TBARS and three-fold increase in glutathione levels were observed in neoplastic tissues. Hexokinase activity and hexose concentration (175%) was found to be increased, whereas glucose-6-phosphatase (33%), fructose-1, 6-bisphosphatase (42%), and G6PD (5 fold) activities were reduced in tumor mass compared to control. Conclusion: Finally, it was revealed that lipid peroxidation was increased with differentially altered carbohydrate metabolism in canine mammary tumors. PMID:28096627

  18. Carbohydrates

    MedlinePlus

    ... glossary girlshealth.gov home http://www.girlshealth.gov/ Home Nutrition Nutrition basics Carbohydrates Carbohydrates Carbohydrates (say: kar-boh-HEYE-drayts) are the body's main source of energy. They are sometimes called "carbs" for short. If ...

  19. Horizontal transfer of carbohydrate metabolism genes into ectomycorrhizal Amanita.

    PubMed

    Chaib De Mares, Maryam; Hess, Jaqueline; Floudas, Dimitrios; Lipzen, Anna; Choi, Cindy; Kennedy, Megan; Grigoriev, Igor V; Pringle, Anne

    2015-03-01

    The genus Amanita encompasses both symbiotic, ectomycorrhizal fungi and asymbiotic litter decomposers; all species are derived from asymbiotic ancestors. Symbiotic species are no longer able to degrade plant cell walls. The carbohydrate esterases family 1 (CE1s) is a diverse group of enzymes involved in carbon metabolism, including decomposition and carbon storage. CE1 genes of the ectomycorrhizal A. muscaria appear diverged from all other fungal homologues, and more similar to CE1s of bacteria, suggesting a horizontal gene transfer (HGT) event. In order to test whether AmanitaCE1s were acquired horizontally, we built a phylogeny of CE1s collected from across the tree of life, and describe the evolution of CE1 genes among Amanita and relevant lineages of bacteria. CE1s of symbiotic Amanita were very different from CE1s of asymbiotic Amanita, and are more similar to bacterial CE1s. The protein structure of one CE1 gene of A. muscaria matched a depolymerase that degrades the carbon storage molecule poly((R)-3-hydroxybutyrate) (PHB). Asymbiotic Amanita do not carry sequence or structural homologues of these genes. The CE1s acquired through HGT may enable novel metabolisms, or play roles in signaling or defense. This is the first evidence for the horizontal transfer of carbohydrate metabolism genes into ectomycorrhizal fungi.

  20. Photosynthetic carbohydrate metabolism in the resurrection plant Craterostigma plantagineum.

    PubMed

    Norwood, M; Truesdale, M R; Richter, A; Scott, P

    2000-02-01

    The resurrection plant Craterostigma plantagineum (Hochst) is able to survive almost complete tissue dehydration when water is withheld from it, and then can rehydrate rapidly on rewatering. This ability is believed to be the result of the accumulation of sucrose in aerial tissues as a result of metabolism of 2-octulose. In this work the metabolic activity of well-watered Craterostigma plantagineum plants has been investigated. It is shown that Craterostigma makes raffinose series oligosaccharides as a product of photosynthesis and translocates them in the phloem. Evidence is also provided that 2-octulose is a product of photosynthesis and accumulates in the leaves over the light period and is mobilized at night. Thus 2-octulose acts as a temporary storage carbohydrate in leaves during photosynthesis in a similar fashion to starch in most C3 plants. Other potential roles of 2-octulose are discussed. Other than these observations Craterostigma plants are very similar to other C3 plants under these conditions.

  1. Temporal Coordination of Carbohydrate Metabolism during Mosquito Reproduction.

    PubMed

    Hou, Yuan; Wang, Xue-Li; Saha, Tusar T; Roy, Sourav; Zhao, Bo; Raikhel, Alexander S; Zou, Zhen

    2015-07-01

    Hematophagous mosquitoes serve as vectors of multiple devastating human diseases, and many unique physiological features contribute to the incredible evolutionary success of these insects. These functions place high-energy demands on a reproducing female mosquito, and carbohydrate metabolism (CM) must be synchronized with these needs. Functional analysis of metabolic gene profiling showed that major CM pathways, including glycolysis, glycogen and sugar metabolism, and citrate cycle, are dramatically repressed at post eclosion (PE) stage in mosquito fat body followed by a sharply increase at post-blood meal (PBM) stage, which were also verified by Real-time RT-PCR. Consistent to the change of transcript and protein level of CM genes, the level of glycogen, glucose and trehalose and other secondary metabolites are also periodically accumulated and degraded during the reproductive cycle respectively. Levels of triacylglycerols (TAG), which represent another important energy storage form in the mosquito fat body, followed a similar tendency. On the other hand, ATP, which is generated by catabolism of these secondary metabolites, showed an opposite trend. Additionally, we used RNA interference studies for the juvenile hormone and ecdysone receptors, Met and EcR, coupled with transcriptomics and metabolomics analyses to show that these hormone receptors function as major regulatory switches coordinating CM with the differing energy requirements of the female mosquito throughout its reproductive cycle. Our study demonstrates how, by metabolic reprogramming, a multicellular organism adapts to drastic and rapid functional changes.

  2. Carbohydrates

    MedlinePlus

    Carbohydrates are one of the main types of nutrients. They are the most important source of energy for your body. Your digestive system changes carbohydrates into glucose (blood sugar). Your body uses this ...

  3. Mangiferin Stimulates Carbohydrate Oxidation and Protects Against Metabolic Disorders Induced by High-Fat Diets

    PubMed Central

    Apontes, Pasha; Liu, Zhongbo; Su, Kai; Benard, Outhiriaradjou; Youn, Dou Y.; Li, Xisong; Li, Wei; Mirza, Raihan H.; Bastie, Claire C.; Jelicks, Linda A.; Pessin, Jeffrey E.; Muzumdar, Radhika H.; Sauve, Anthony A.

    2014-01-01

    Excessive dietary fat intake causes systemic metabolic toxicity, manifested in weight gain, hyperglycemia, and insulin resistance. In addition, carbohydrate utilization as a fuel is substantially inhibited. Correction or reversal of these effects during high-fat diet (HFD) intake is of exceptional interest in light of widespread occurrence of diet-associated metabolic disorders in global human populations. Here we report that mangiferin (MGF), a natural compound (the predominant constituent of Mangifera indica extract from the plant that produces mango), protected against HFD-induced weight gain, increased aerobic mitochondrial capacity and thermogenesis, and improved glucose and insulin profiles. To obtain mechanistic insight into the basis for these effects, we determined that mice exposed to an HFD combined with MGF exhibited a substantial shift in respiratory quotient from fatty acid toward carbohydrate utilization. MGF treatment significantly increased glucose oxidation in muscle of HFD-fed mice without changing fatty acid oxidation. These results indicate that MGF redirects fuel utilization toward carbohydrates. In cultured C2C12 myotubes, MGF increased glucose and pyruvate oxidation and ATP production without affecting fatty acid oxidation, confirming in vivo and ex vivo effects. Furthermore, MGF inhibited anaerobic metabolism of pyruvate to lactate but enhanced pyruvate oxidation. A key target of MGF appears to be pyruvate dehydrogenase, determined to be activated by MGF in a variety of assays. These findings underscore the therapeutic potential of activation of carbohydrate utilization in correction of metabolic syndrome and highlight the potential of MGF to serve as a model compound that can elicit fuel-switching effects. PMID:24848064

  4. Carbohydrate utilization and metabolism is highly differentiated in Agaricus bisporus

    PubMed Central

    2013-01-01

    Background Agaricus bisporus is commercially grown on compost, in which the available carbon sources consist mainly of plant-derived polysaccharides that are built out of various different constituent monosaccharides. The major constituent monosaccharides of these polysaccharides are glucose, xylose, and arabinose, while smaller amounts of galactose, glucuronic acid, rhamnose and mannose are also present. Results In this study, genes encoding putative enzymes from carbon metabolism were identified and their expression was studied in different growth stages of A. bisporus. We correlated the expression of genes encoding plant and fungal polysaccharide modifying enzymes identified in the A. bisporus genome to the soluble carbohydrates and the composition of mycelium grown compost, casing layer and fruiting bodies. Conclusions The compost grown vegetative mycelium of A. bisporus consumes a wide variety of monosaccharides. However, in fruiting bodies only hexose catabolism occurs, and no accumulation of other sugars was observed. This suggests that only hexoses or their conversion products are transported from the vegetative mycelium to the fruiting body, while the other sugars likely provide energy for growth and maintenance of the vegetative mycelium. Clear correlations were found between expression of the genes and composition of carbohydrates. Genes encoding plant cell wall polysaccharide degrading enzymes were mainly expressed in compost-grown mycelium, and largely absent in fruiting bodies. In contrast, genes encoding fungal cell wall polysaccharide modifying enzymes were expressed in both fruiting bodies and vegetative mycelium, but different gene sets were expressed in these samples. PMID:24074284

  5. Carbohydrate, protein, and fat metabolism during exercise after oral carnitine supplementation in humans.

    PubMed

    Broad, Elizabeth M; Maughan, Ronald J; Galloway, Stuart D

    2008-12-01

    Twenty nonvegetarian active males were pair-matched and randomly assigned to receive 2 g of L-carnitine L-tartrate (LC) or placebo per day for 2 wk. Participants exercised for 90 min at 70% VO2max after 2 days of a prescribed diet (M +/- SD: 13.6 +/- 1.6 MJ, 57% carbohydrate, 15% protein, 26% fat, 2% alcohol) before and after supplementation. Results indicated no change in carbohydrate oxidation, nitrogen excretion, branched-chain amino acid oxidation, or plasma urea during exercise between the beginning and end of supplementation in either group. After 2 wk of LC supplementation the plasma ammonia response to exercise tended to be suppressed (0 vs. 2 wk at 60 min exercise, 97 +/- 26 vs. 80 +/- 9, and 90 min exercise, 116 +/- 47 vs. 87 +/- 25 micromol/L), with no change in the placebo group. The data indicate that 2 wk of LC supplementation does not affect fat, carbohydrate, and protein contribution to metabolism during prolonged moderate-intensity cycling exercise. The tendency toward suppressed ammonia accumulation, however, indicates that oral LC supplementation might have the potential to reduce the metabolic stress of exercise or alter ammonia production or removal, which warrants further investigation.

  6. Endocrine regulation of carbohydrate metabolism in hypometabolic animals

    NASA Technical Reports Server (NTRS)

    Musacchia, X. J.

    1988-01-01

    Experimental hypothermia and natural hibernation are two forms of hypometabolism with recognized physiological changes, including depression of endocrine and metabolic functions. To better understand functional changes, helox (i.e., helium and oxygen (80:20) mixtures) and low ambient temperatures have been used to induce hypothermia in hamsters and rats. Both clinical and biological survival, i.e., survival without recovery and survival with recovery from hypothermia, respectively, are related to depth and length of hypothermia. In the rat, body temperatures of 15 degrees C for periods greater than 6-10 h greatly restrict biological survival. The role of glucocorticoids in enhancing thermogenic capacity of rats was assessed using triamcinolone [correction of triamcinalone] acetonide. In the hamster, treatment with cortisone acetate prolonged both clinical and biological survival. Hypothermic hamsters continue utilizing circulating glucose until they become hypoglycemic and die. Hypothermic rats do not utilize glucose and respond with a significant hypoinsulinema. The role of endocrines in the regulation of carbohydrate homeostasis and metabolism differs in hibernation and hypothermia. Glucocorticoids influence the hypothermic response in both species, specifically by prolonging induction of hypothermia in rats and by prolonging survival in hypothermic hamsters.

  7. Carbohydrate metabolism in the course of intrahepatic cholestasis in pregnancy.

    PubMed

    Wójcicka-Jagodzińska, J; Kuczyńska-Sicińska, J; Czajkowski, K; Smolarczyk, R

    1989-10-01

    Glucose metabolism was evaluated in pregnant women with clinically and biochemically demonstrated intrahepatic cholestasis. Laboratory investigations included measurements of serum glucose concentrations on fasting and 2 hours after breakfast, the glucose tolerance test (100 gm oral glucose load), and 24-hour glycemia profile. All patients were admitted to the II Department of Obstetrics and Gynecology, Institute of Obstetrics and Gynecology of the Medical School in Warsaw, Poland. None of the patients exhibited manifest diabetes mellitus or had any clinical history suggestive of previous diabetes. The serum samples collected 2 hours after breakfast demonstrated higher glucose concentrations in women with intrahepatic cholestasis when compared with healthy control subjects. The glucose tolerance tests demonstrated consistently higher concentrations of glucose in blood serum samples after loading in the study group. The 24-hour glycemia profile showed greater glucose concentrations in serum samples collected 2 hours after breakfast and after supper. These results suggest that in the course of cholestasis in pregnancy, visible changes occur in the carbohydrate metabolism of the pregnant woman.

  8. Whey or Casein Hydrolysate with Carbohydrate for Metabolism and Performance in Cycling.

    PubMed

    Oosthuyse, T; Carstens, M; Millen, A M E

    2015-07-01

    The protein type most suitable for ingestion during endurance exercise is undefined. This study compared co-ingestion of either 15 g/h whey or casein hydrolysate with 63 g/h fructose: maltodextrin (0.8:1) on exogenous carbohydrate oxidation, exercise metabolism and performance. 2 h postprandial, 8 male cyclists ingested either: carbohydrate-only, carbohydrate-whey hydrolysate, carbohydrate-casein hydrolysate or placebo-water in a crossover, double-blind design during 2 h of exercise at 60%W max followed by a 16-km time trial. Data were evaluated by magnitude-based inferential statistics. Exogenous carbohydrate oxidation, measured from (13)CO2 breath enrichment, was not substantially influenced by co-ingestion of either protein hydrolysate. However, only co-ingestion of carbohydrate-casein hydrolysate substantially decreased (98% very likely decrease) total carbohydrate oxidation (mean±SD, 242±44; 258±47; 277±33 g for carbohydrate-casein, carbohydrate-whey and carbohydrate-only, respectively) and substantially increased (93% likely increase) total fat oxidation (92±14; 83±27; 73±19 g) compared with carbohydrate-only. Furthermore, only carbohydrate-casein hydrolysate ingestion resulted in a faster time trial (-3.6%; 90% CI: ±3.2%) compared with placebo-water (95% likely benefit). However, neither protein hydrolysate enhanced time trial performance when compared with carbohydrate-only. Under the conditions of this study, ingesting carbohydrate-casein, but not carbohydrate-whey hydrolysate, favourably alters metabolism during prolonged moderate-strenuous cycling without substantially altering cycling performance compared with carbohydrate-only.

  9. Effect of alcohol consumption on hormones involved in carbohydrate and lipid metabolism in premenopausal women

    SciTech Connect

    Law, J.S.; Bhathena, S.J.; Kim, Y.C.; Berlin, E.; Judd, J.T.; Reichman, M.E.; Taylor, P.R.; Schatzkin, A. NCI, Bethesda, MD )

    1991-03-15

    Alcohol consumption alters carbohydrate and lipid metabolism which are in part regulated by pancreatic and adrenal hormones. The menstrual cycle per se produces changes in several peptide and steroid hormones besides the sex hormones. The authors investigated the effect of moderate alcohol consumption on plasma hormone levels in 40 premenopausal women. The subjects were fed controlled diets containing 35% of calories from fat. In a random crossover design women were given either alcohol or a soft-drink of equal caloric value for 3 menstrual cycles. Fasting blood samples were collected in the third cycle during follicular, ovulatory and luteal phases. Plasma dehydroepiandrosterone-sulphate (DHEA-S), insulin, glucagon and cortisol levels were measured by radioimmunoassay. Moderate alcohol consumption had no effect on plasma insulin and DHEA-S levels but significantly increased glucagon and cortisol levels. Menstrual cycle per se affected plasma glucagon level in that the levels were higher during follicular phase than luteal phase. Thus, changes in carbohydrate and lipid metabolism following alcohol consumption are mediated in part by alterations in hormones involved in their metabolism.

  10. Carbohydrates.

    PubMed

    Cocinero, Emilio J; Çarçabal, Pierre

    2015-01-01

    Although carbohydrates represent one of the most important families of biomolecules, they remain under-studied in comparison to the other biomolecular families (peptides, nucleobases). Beyond their best-known function of energy source in living systems, they act as mediator of molecular recognition processes, carrying molecular information in the so-called "sugar code," just to name one of their countless functions. Owing to their high conformational flexibility, they encode extremely rich information conveyed via the non-covalent hydrogen bonds within the carbohydrate and with other biomolecular assemblies, such as peptide subunits of proteins. Over the last decade there has been tremendous progress in the study of the conformational preferences of neutral oligosaccharides, and of the interactions between carbohydrates and various molecular partners (water, aromatic models, and peptide models), using vibrational spectroscopy as a sensitive probe. In parallel, other spectroscopic techniques have recently become available to the study of carbohydrates in the gas phase (microwave spectroscopy, IRMPD on charged species).

  11. Metabolic and hormonal responses to body carbohydrate store depletion followed by high or low carbohydrate meal in sedentary and physically active subjects.

    PubMed

    Mikulski, T; Ziemba, A; Nazar, K

    2010-04-01

    The study was designed to determine metabolic and hormonal responses to acute modification of body carbohydrate stores by exercise and subsequent meals and to find out whether the responses depend on the training status of subjects. Nine sedentary students and 10 endurance athletes took part in four experimental sessions. During control session, after overnight fast oxygen uptake and CO2 production were measured and blood glucose, free fatty acids (FFA), insulin (I), leptin (L), growth hormone (GH), testosterone (T), catecholamines, ACTH and cortisol were determined. The remaining sessions were preceded by 1.5 h exercise at 70% HRmax in the evening followed by 12-16 hrs fast till morning when subjects ate either high-carbohydrate (H-CHO) or low-carbohydrate (L-CHO) meal or fasted. Respiratory gases and blood samples were collected before and 2 hours after meal. In glycogen depleted subjects respiratory quotient (RQ), I, norepinephrine (NE) and L decreased, whilst other variables were unaltered. Changes in I and NE were greater in athletes than in sedentary subjects. After H-CHO RQ, blood glucose, I and NE increased and FFA, GH and T decreased. The latter effect was greater in athletes than in untrained subjects. After L-CHO, RQ was at the fasting level and FFA increased only in sedentary group. In both groups I increased and GH and T decreased. Neither meal affected L concentration. In conclusion, hormonal and metabolic changes observed after depleting carbohydrate stores resemble those occurring during starvation. Composition of the ingested meal affects postprandial metabolism, which additionally depends on the subjects' training status.

  12. [Contemporary outlook on prevention and correction of early disturbances of carbohydrate metabolism in cardiological practice].

    PubMed

    Mamedov, M N; Poddubskaia, E A; Kovrigina, M N; Ugurchieva, Z O; Didigova, R T

    2012-01-01

    In the search for effective means of prevention and detection of early markers of type 2 diabetes mellitus (DM) the scientists take an interest for early disturbances of carbohydrate metabolism. In this work we present data of international clinical studies confirming that early disturbances of carbohydrate metabolism appear to be an independent risk factor of cardiovascular diseases. In this connection possibilities of prevention and treatment of early disturbances of carbohydrate metabolism are discussed. We also present classification of antihyperglycemic drugs and analysis of their mechanism of action and efficacy from the point of view of evidence based medicine. The data presented evidence that successful primary prevention of type 2 DM at the stage of early disturbances of carbohydrate metabolism can facilitate lowering of cardiovascular complications.

  13. TPhP exposure disturbs carbohydrate metabolism, lipid metabolism, and the DNA damage repair system in zebrafish liver

    NASA Astrophysics Data System (ADS)

    Du, Zhongkun; Zhang, Yan; Wang, Guowei; Peng, Jianbiao; Wang, Zunyao; Gao, Shixiang

    2016-02-01

    Triphenyl phosphate is a high production volume organophosphate flame retardant that has been detected in multiple environmental media at increasing concentrations. The environmental and health risks of triphenyl phosphate have drawn attention because of the multiplex toxicity of this chemical compound. However, few studies have paid close attention to the impacts of triphenyl phosphate on liver metabolism. We investigated hepatic histopathological, metabolomic and transcriptomic responses of zebrafish after exposure to 0.050 mg/L and 0.300 mg/L triphenyl phosphate for 7 days. Metabolomic analysis revealed significant changes in the contents of glucose, UDP-glucose, lactate, succinate, fumarate, choline, acetylcarnitine, and several fatty acids. Transcriptomic analysis revealed that related pathways, such as the glycosphingolipid biosynthesis, PPAR signaling pathway and fatty acid elongation, were significantly affected. These results suggest that triphenyl phosphate exposure markedly disturbs hepatic carbohydrate and lipid metabolism in zebrafish. Moreover, DNA replication, the cell cycle, and non-homologous end-joining and base excision repair were strongly affected, thus indicating that triphenyl phosphate hinders the DNA damage repair system in zebrafish liver cells. The present study provides a systematic analysis of the triphenyl phosphate-induced toxic effects in zebrafish liver and demonstrates that low concentrations of triphenyl phosphate affect normal metabolism and cell cycle.

  14. TPhP exposure disturbs carbohydrate metabolism, lipid metabolism, and the DNA damage repair system in zebrafish liver

    PubMed Central

    Du, Zhongkun; Zhang, Yan; Wang, Guowei; Peng, Jianbiao; Wang, Zunyao; Gao, Shixiang

    2016-01-01

    Triphenyl phosphate is a high production volume organophosphate flame retardant that has been detected in multiple environmental media at increasing concentrations. The environmental and health risks of triphenyl phosphate have drawn attention because of the multiplex toxicity of this chemical compound. However, few studies have paid close attention to the impacts of triphenyl phosphate on liver metabolism. We investigated hepatic histopathological, metabolomic and transcriptomic responses of zebrafish after exposure to 0.050 mg/L and 0.300 mg/L triphenyl phosphate for 7 days. Metabolomic analysis revealed significant changes in the contents of glucose, UDP-glucose, lactate, succinate, fumarate, choline, acetylcarnitine, and several fatty acids. Transcriptomic analysis revealed that related pathways, such as the glycosphingolipid biosynthesis, PPAR signaling pathway and fatty acid elongation, were significantly affected. These results suggest that triphenyl phosphate exposure markedly disturbs hepatic carbohydrate and lipid metabolism in zebrafish. Moreover, DNA replication, the cell cycle, and non-homologous end-joining and base excision repair were strongly affected, thus indicating that triphenyl phosphate hinders the DNA damage repair system in zebrafish liver cells. The present study provides a systematic analysis of the triphenyl phosphate-induced toxic effects in zebrafish liver and demonstrates that low concentrations of triphenyl phosphate affect normal metabolism and cell cycle. PMID:26898711

  15. The Roles of Vitamin A in the Regulation of Carbohydrate, Lipid, and Protein Metabolism

    PubMed Central

    Chen, Wei; Chen, Guoxun

    2014-01-01

    Currently, two-thirds of American adults are overweight or obese. This high prevalence of overweight/obesity negatively affects the health of the population, as obese individuals tend to develop several chronic diseases, such as type 2 diabetes and cardiovascular diseases. Due to obesity’s impact on health, medical costs, and longevity, the rise in the number of obese people has become a public health concern. Both genetic and environmental/dietary factors play a role in the development of metabolic diseases. Intuitively, it seems to be obvious to link over-nutrition to the development of obesity and other metabolic diseases. However, the underlying mechanisms are still unclear. Dietary nutrients not only provide energy derived from macronutrients, but also factors such as micronutrients with regulatory roles. How micronutrients, such as vitamin A (VA; retinol), regulate macronutrient homeostasis is still an ongoing research topic. As an essential micronutrient, VA plays a key role in the general health of an individual. This review summarizes recent research progress regarding VA’s role in carbohydrate, lipid, and protein metabolism. Due to the large amount of information regarding VA functions, this review focusses on metabolism in metabolic active organs and tissues. Additionally, some perspectives for future studies will be provided. PMID:26237385

  16. Effects of alkali stress on growth, free amino acids and carbohydrates metabolism in Kentucky bluegrass (Poa pratensis).

    PubMed

    Zhang, Pingping; Fu, Jinmin; Hu, Longxing

    2012-10-01

    Soil alkalization is one of the most prominent adverse environmental factors limiting plant growth, while alkali stress affects amino acids and carbohydrates metabolism. The objective of this study was conducted to investigate the effects of alkali stress on growth, amino acids and carbohydrates metabolism in Kentucky bluegrass (Poa pratensis). Seventy-day-old plants were subjected to four pH levels: 6.0 (control), 8.0 (low), 9.4 (moderate) and 10.3 (severe) for 7 days. Moderate to severe alkali stress (pH >9.4) caused a significant decline in turf quality and growth rate in Kentucky bluegrass. Soluble protein was unchanged in shoots, but decreased in roots as pH increased. The levels of amino acids was kept at the same level as control level at 4 days after treatment (DAT) in shoots, but greater at 7 DAT, when plants were subjected to severe (pH 10.3) alkali stress. The alkali stressed plants had a greater level of starch, water soluble carbohydrate and sucrose content, but lower level of fructose and glucose. Fructan and total non-structural carbohydrate (TNC) increased at 4 DAT and decreased at 7 DAT for alkali stressed plants. These results suggested that the decrease in fructose and glucose contributed to the growth reduction under alkali stress, while the increase in amino acids, sucrose and storage form of carbohydrate (fructan, starch) could be an adaptative mechanism in Kentucky bluegrass under alkali stress.

  17. Metabolic syndrome in childhood from impaired carbohydrate metabolism to nonalcoholic fatty liver disease.

    PubMed

    Manco, Melania

    2011-10-01

    Compelling evidence supports the concept that nonalcoholic fatty liver disease (NAFLD) represents the hepatic component of metabolic syndrome (MetS). Intrahepatic fat seems to predict more strongly than does visceral adiposity an individual's cardiovascular risk and the likelihood that metabolic abnormalities are present in youth. Young individuals with fatty liver are more insulin resistant and present with a higher prevalence of metabolic abnormalities than do individuals without intrahepatic fat accumulation. They also present with a certain endothelial dysfunction and greater carotid intima-media thickness. Conversely, youth with MetS seem to have an increased risk of developing liver inflammation, a condition termed nonalcoholic steatohepatitis (NASH), and fibrosis. In the context of MetS, the liver is central in that it can drive both hepatic and systemic insulin resistance, trigger low-grade inflammation, and promote atherogenic processes. In the context of MetS, NAFLD and altered carbohydrate metabolism track from childhood to adulthood. Thus, prevention, recognition, and effective treatment of these two abnormalities may limit the burden of morbidity and mortality associated with obesity and may delay onset of cardiovascular disease in early adulthood. The present review aims at systematically presenting evidence of the critical interplay of fatty liver and altered glucose metabolism in youth. It attempts to provide pathogenetic explanations for such an association and the rationale for its treatment, with particular regard to nutritional interventions. Key teaching points: Overweight and obese youth should be screened for fatty liver disease once after puberty by liver function tests and ultrasonography. Screening for fatty liver should be accurately performed in young patients with features of metabolic syndrome. Obese patients with fatty liver are at increased risk for altered glucose metabolism, thus they should undergo an oral glucose tolerance test

  18. Metabolism and growth of juveniles of Litopenaeus vannamei: effect of salinity and dietary carbohydrate levels.

    PubMed

    Rosas, C; Cuzon, G; Gaxiola, G; Le Priol, Y; Pascual, C; Rossignyol, J; Contreras, F; Sanchez, A; Van Wormhoudt, A

    2001-04-30

    The present study was designed to understand how carbohydrate (CBH) and protein metabolism are related in the penaeid shrimp Litopenaeus vannamei. With this information, we obtained a comprehensive schedule of the protein-carbohydrate metabolism including enzymatic, energetic, and functional aspects. We used salinity to determine its role as a modulator of the protein-carbohydrate metabolism in shrimp. Two experiments were designed. The first experiment evaluated the effect of CBH-salinity combinations in growth and survival, and hemolymph glucose, protein, and ammonia levels, digestive gland glycogen, osmotic pressure, and glutamate dehydrogenase (GDH) of L. vannamei juveniles acclimated during 18 days at a salinity of 15 per thousand and 40 per thousand. The second experiment was done to evaluate the effect of dietary CBH level on pre- and postprandial oxygen consumption, ammonia excretion, and the oxygen-nitrogen ratio (O/N) of juvenile L. vannamei in shrimps acclimated at 40 per thousand salinity. We also evaluated the ability of shrimp to carbohydrate adaptation. We made phosphoenolpyruvate carboxykinase (PECPK) and hexokinase activity measurements after a change in dietary carbohydrate levels at different times during 10 days. The growth rate depended on the combination salinity-dietary CBH-protein level. The maximum growth rate was obtained in shrimps maintained at 15 per thousand salinity and with a diet containing low CBH and high protein. The protein in hemolymph is related to the dietary protein levels; high dietary protein levels produced a high protein concentration in hemolymph. This suggests hemolymph is able to store proteins after a salinity acclimation. Depending on the salinity, the hemolymph proteins could be used as a source of osmotic effectors or as metabolic energy. The O/N values obtained show that shrimp used proteins as a source of energy, mainly when shrimps were fed with low CBH. The role played by postprandial nitrogen excretion (PPNE

  19. Distinct regulation in inflorescence carbohydrate metabolism according to grapevine cultivars during floral development.

    PubMed

    Sawicki, Mélodie; Jacquens, Lucile; Baillieul, Fabienne; Clément, Christophe; Vaillant-Gaveau, Nathalie; Jacquard, Cédric

    2015-07-01

    Carbohydrate metabolism is important in plant sexual reproduction because sugar contents are determining factors for both flower initiation and floral organ development. In woody plants, flowering represents the most energy-consuming step crucial to reproductive success. Nevertheless, in these species, the photosynthesis performed by flowers supplies the carbon required for reproduction. In grapevine (Vitis vinifera), the inflorescence has a specific status because this organ imports carbohydrates at the same time as it exports photoassimilates. In this study, fluctuations in carbohydrate metabolism were monitored by analyzing gas exchanges, photosynthetic electron transport capacity, carbohydrate contents and some activities of carbohydrate metabolism enzymes, in the inflorescences of Pinot noir and Gewurztraminer, two cultivars with a different sensitivity to coulure phenomenon. Our results showed that photosynthetic activity and carbohydrate metabolism are clearly different and differently regulated during the floral development in the two cultivars. Indeed, the regulation of the linear electron flow and the cyclic electron flow is not similar. Moreover, the regulation of PSII activity, with a higher Y(NPQ)/Y(NO) ratio in Gewurztraminer, can be correlated with the higher protection of the photosynthetic chain and consequently with the higher yield under optimal conditions of this cultivar. At least, our results showed a higher photosynthetic activity and a better protection of PSI in Pinot noir during the floral development.

  20. High-protein-low-carbohydrate diet: deleterious metabolic and cardiovascular effects depend on age.

    PubMed

    Bedarida, Tatiana; Baron, Stephanie; Vessieres, Emilie; Vibert, Francoise; Ayer, Audrey; Marchiol-Fournigault, Carmen; Henrion, Daniel; Paul, Jean-Louis; Noble, Florence; Golmard, Jean-Louis; Beaudeux, Jean-Louis; Cottart, Charles-Henry; Nivet-Antoine, Valerie

    2014-09-01

    High-protein-low-carbohydrate (HP-LC) diets have become widespread. Yet their deleterious consequences, especially on glucose metabolism and arteries, have already been underlined. Our previous study (2) has already shown glucose intolerance with major arterial dysfunction in very old mice subjected to an HP-LC diet. The hypothesis of this work was that this diet had an age-dependent deleterious metabolic and cardiovascular outcome. Two groups of mice, young and adult (3 and 6 mo old), were subjected for 12 wk to a standard or to an HP-LC diet. Glucose and lipid metabolism was studied. The cardiovascular system was explored from the functional stage with Doppler-echography to the molecular stage (arterial reactivity, mRNA, immunohistochemistry). Young mice did not exhibit any significant metabolic modification, whereas adult mice presented marked glucose intolerance associated with an increase in resistin and triglyceride levels. These metabolic disturbances were responsible for cardiovascular damages only in adult mice, with decreased aortic distensibility and left ventricle dysfunction. These seemed to be the consequence of arterial dysfunctions. Mesenteric arteries were the worst affected with a major oxidative stress, whereas aorta function seemed to be maintained with an appreciable role of cyclooxygenase-2 to preserve endothelial function. This study highlights for the first time the age-dependent deleterious effects of an HP-LC diet on metabolism, with glucose intolerance and lipid disorders and vascular (especially microvessels) and cardiac functions. This work shows that HP-LC lead to equivalent cardiovascular alterations, as observed in very old age, and underlines the danger of such diet.

  1. [Carbohydrate metabolism in the brain in comatose states].

    PubMed

    Khapiĭ, Kh Kh; Gruzman, A B

    1990-01-01

    The article confirms an earlier discovered phenomenon that during comas and in post-coma periods the brain releases glucose and consumes lactate. It is suggested that the phenomenon is based on glucogenesis taking place in the brain from non-carbohydrate glucose precursors, which is phylogenetically predetermined and biologically expedient.

  2. Leaf responses of micropropagated apple plants to water stress: nonstructural carbohydrate composition and regulatory role of metabolic enzymes.

    PubMed

    Li, Tian H; Li, Shao H

    2005-04-01

    We examined changes in nonstructural carbohydrate biosynthesis and activities of related enzymes in leaves of micropropagated apple plants (Malus domestica Borkh. cv. 'NaganoFuji') in response to water stress, with particular emphasis on the enzymes associated with sorbitol, sucrose and starch metabolism. Water stress resulted in the accumulation of photosynthates in leaves, mainly sorbitol, sucrose, glucose and fructose, accompanied by a reduction in starch concentration. Correlation and path analysis indicated that water stress affected the partitioning of newly fixed carbon among terminal products. In response to water stress, ADP-glucose-pyrophosphorylase (ADPGPPase) activity decreased, becoming a critical and limiting step in shifting partitioning of photosynthetically fixed carbon. Amylase and ADPGPPase affected sucrose and sorbitol metabolism, mainly by regulating substrate supply; however, competition for limited substrate had a greater effect on the biosynthesis of sorbitol than of sucrose. Starch metabolism was also strictly regulated by ADPGPPase and amylase, whereas other related enzymes were downstream of the pathway for synthesis and degradation of carbohydrates and thus had relatively little effect on starch metabolism. Sorbitol dehydrogenase and sucrose phosphate synthase were critical regulators of sorbitol and sucrose metabolism, respectively.

  3. Carbohydrate metabolism before and after dehiscence in the recalcitrant pollen of pumpkin (Cucurbita pepo L.).

    PubMed

    Carrizo García, C; Guarnieri, M; Pacini, E

    2015-05-01

    Pumpkin (Cucurbita pepo L.) pollen is starchy, sucrose-poor and recalcitrant, features opposite to those of several model species; therefore, some differences in carbohydrate metabolism could be expected in this species. By studying pumpkin recalcitrant pollen, the objective was to provide new biochemical evidence to improve understanding of how carbohydrate metabolism might be involved in pollen functioning in advanced stages. Four stages were analysed: immature pollen from 1 day before anthesis, mature pollen, mature pollen exposed to the environment for 7 h, and pollen rehydrated in a culture medium. Pollen viability, water and carbohydrate content and activity of enzymes involved in carbohydrate metabolism were quantified in each stage. Pollen viability and water content dropped quickly after dehiscence, as expected. The slight changes in carbohydrate concentration and enzyme activity during pollen maturation contrast with major changes recorded with ageing and rehydration. Pumpkin pollen seems highly active and closely related to its surrounding environment in all the stages analysed; the latter is particularly evident among insoluble sucrolytic enzymes, mainly wall-bound acid invertase, which would be the most relevant for sucrose cleavage. Each stage was characterised by a particular metabolic/enzymatic profile; some particular features, such as the minor changes during maturation, fast sucrolysis upon rehydration or sharp decrease in insoluble sucrolytic activity with ageing seem to be related to the lack of dormancy and recalcitrant nature of pumpkin pollen.

  4. Skeletal muscle metabolic gene response to carbohydrate feeding during exercise in the heat

    PubMed Central

    2013-01-01

    Background Heat stress down-regulates mitochondrial function, while carbohydrate supplementation attenuates the exercise induced stimulation of mitochondrial biogenesis in humans. The effects of exogenous carbohydrate during exercise in the heat on metabolic mRNA have not been investigated in humans. The purpose of this study was to determine the impact of exercise with and without carbohydrate supplementation on skeletal muscle metabolic response in the heat. Methods Eight recreationally active males (4.05 ± 0.2 L.min-1) completed 2 trials which included 1 hr of cycling at 70% workload max and 3 hr recovery in a hot environment. Both trials were conducted in a climate controlled environmental chamber (38°C and 40% RH). The trials differed by the consumption of either a 6% carbohydrate (CHO) containing beverage (8 ml.kg-1.hr-1) or placebo (P) during exercise in random order. Muscle biopsies were obtained from the vastus lateralis before exercise, immediately post-exercise and at the end of the 3 hr recovery period. Muscle was analyzed for muscle glycogen and mRNA related to metabolic and mitochondrial development (MFN2, PGC-1α, GLUT4, UCP3). Expired gases were measured to determine whole body substrate use during exercise. Results Carbohydrate oxidation and muscle glycogen utilization did not differ between trials, whereas fat oxidation was elevated during exercise in P. Exercise caused an increase in PGC-1α, and GLUT4 (P < 0.05) independent of exogenous carbohydrate provision. Carbohydrate consumption attenuated the mRNA response in UCP3 (P < 0.05). Conclusions This study indicates that the provision of exogenous carbohydrate attenuates the stimulation of mRNA expression of UCP3 following exercise in the heat. PMID:24034227

  5. [Disorders of carbohydrate metabolism, dyslipidemia, and bone metabolic disease after hematopoietic stem cell transplantation].

    PubMed

    Wędrychowicz, Anna; Starzykk, Jerzy

    2013-01-01

    Among long-term survivors after hematopoietic stem cell transplantation (HSCT) late endocrine complications are observed in 20-50%. Very often these complications influence significantly the patient´s life and have to be treated till the end of life. Their proper prevention and monitoring are extremely important in patients who underwent HSCT during childhood. Since the 90s of the last millennium/century, thyroid dysfunction, disorders of somatic and sexual development, and disturbances of fertility have been presented in several publications. In the paper, less known endocrine complications after HSCT published in the last years are discussed. Disorders of carbohydrate metabolism, post-transplant diabetes and insulin resistance are presented. Moreover, dyslipidemia, hypertension, and post-transplant bone metabolic disease are demonstrated/shown. The paper describes the etiopathogenesis, methods of prevention as well as treatment and the results of the treatment of these endocrine complications after HSCT. Moreover, actual recommendations for screening and prevention of endocrine complications in long-term HCT survivors are presented.

  6. Inulin oligofructose attenuates metabolic syndrome in high-carbohydrate, high-fat diet-fed rats.

    PubMed

    Kumar, Senthil A; Ward, Leigh C; Brown, Lindsay

    2016-11-01

    Prebiotics alter bacterial content in the colon, and therefore could be useful for obesity management. We investigated the changes following addition of inulin oligofructose (IO) in the food of rats fed either a corn starch (C) diet or a high-carbohydrate, high-fat (H) diet as a model of diet-induced metabolic syndrome. IO did not affect food intake, but reduced body weight gain by 5·3 and 12·3 % in corn starch+inulin oligofructose (CIO) and high-carbohydrate, high-fat with inulin oligofructose (HIO) rats, respectively. IO reduced plasma concentrations of free fatty acids by 26·2 % and TAG by 75·8 % in HIO rats. IO increased faecal output by 93·2 %, faecal lipid excretion by 37·9 % and weight of caecum by 23·4 % and colon by 41·5 % in HIO rats. IO improved ileal morphology by reducing inflammation and improving the density of crypt cells in HIO rats. IO attenuated H diet-induced increases in abdominal fat pads (C 275 (sem 19), CIO 264 (sem 40), H 688 (sem 55), HIO 419 (sem 32) mg/mm tibial length), fasting blood glucose concentrations (C 4·5 (sem 0·1), CIO 4·2 (sem 0·1), H 5·2 (sem 0·1), HIO 4·3 (sem 0·1) mmol/l), systolic blood pressure (C 124 (sem 2), CIO 118 (sem 2), H 152 (sem 2), HIO 123 (sem 3) mmHg), left ventricular diastolic stiffness (C 22·9 (sem 0·6), CIO 22·9 (sem 0·5), H 27·8 (sem 0·5), HIO 22·6 (sem 1·2)) and plasma alanine transaminase (C 29·6 (sem 2·8), CIO 32·1 (sem 3·0), H 43·9 (sem 2·6), HIO 33·6 (sem 2·0) U/l). IO attenuated H-induced increases in inflammatory cell infiltration in the heart and liver, lipid droplets in the liver and plasma lipids as well as impaired glucose and insulin tolerance. These results suggest that increasing soluble fibre intake with IO improves signs of the metabolic syndrome by decreasing gastrointestinal carbohydrate and lipid uptake.

  7. Scorpions regulate their energy metabolism towards increased carbohydrate oxidation in response to dehydration.

    PubMed

    Kalra, Bhawna; Gefen, Eran

    2012-08-01

    Scorpions successfully inhabit some of the most arid habitats on earth. During exposure to desiccating stress water is mobilized from the scorpion hepatopancreas to replenish the hemolymph and retain hydration and osmotic stability. Carbohydrate catabolism is advantageous under these conditions as it results in high metabolic water production rate, as well as the release of glycogen-bound water. Hypothesizing that metabolic fuel utilization in scorpions is regulated in order to boost body water management under stressful conditions we used a comparative approach, studying energy metabolism during prolonged desiccation in four species varying in resistance performance. We used respirometry for calculating respiratory gas exchange ratios, indicative of metabolic fuel utilization, and measured metabolic fuel contents in the scorpion hepatopancreas. We found that hydrated scorpions used a mixture of metabolic fuels (respiratory exchange rates, RER~0.9), but a shift towards carbohydrate catabolism was common during prolonged desiccation stress. Furthermore, the timing of metabolic shift to exclusive carbohydrate oxidation (RER not different from 1.0) was correlated with desiccation resistance of the respective studied species, suggesting triggering by alterations to hemolymph homeostasis.

  8. Programming effects of high-carbohydrate feeding of larvae on adult glucose metabolism in zebrafish, Danio rerio.

    PubMed

    Fang, Liu; Liang, Xu-Fang; Zhou, Yi; Guo, Xiao-Ze; He, Yan; Yi, Ti-Lin; Liu, Li-Wei; Yuan, Xiao-Chen; Tao, Ya-Xiong

    2014-03-14

    The aim of the present study was to determine the potential long-term metabolic effects of early nutritional programming on carbohydrate utilisation in adult zebrafish (Danio rerio). High-carbohydrate diets were fed to fish during four ontogenetic stages: from the first-feeding stage to the end of the yolk-sac larval stage; from the first-feeding stage to 2 d after yolk-sac exhaustion; after yolk-sac exhaustion for 3 or 5 d. The carbohydrate stimuli significantly increased the body weight of the first-feeding groups in the short term. The expression of genes was differentially regulated by the early dietary intervention. The high-carbohydrate diets resulted in decreased plasma glucose levels in the adult fish. The mRNA levels and enzyme activities of glucokinase, pyruvate kinase, α-amylase and sodium-dependent glucose co-transporter 1 were up-regulated in the first-feeding groups. There was no significant change in the mRNA levels of glucose-6-phosphatase (G6Pase) in any experimental group, and the activity of G6Pase enzyme in the FF-5 (first feeding to 2 d after yolk-sac exhaustion) group was significantly different from that of the other groups. The expression of phosphoenolpyruvate carboxykinase gene in all the groups was significantly decreased. In the examined early programming range, growth performance was not affected. Taken together, data reported herein indicate that the period ranging from the polyculture to the external feeding stage is an important window for potential modification of the long-term physiological functions. In conclusion, the present study demonstrates that it is possible to permanently modify carbohydrate digestion, transport and metabolism of adult zebrafish through early nutritional programming.

  9. Enzymes and Metabolites in Carbohydrate Metabolism of Desiccation Tolerant Plants.

    PubMed

    Zhang, Qingwei; Song, Xiaomin; Bartels, Dorothea

    2016-12-15

    Resurrection plants can tolerate extreme water loss. Substantial sugar accumulation is a phenomenon in resurrection plants during dehydration. Sugars have been identified as one important factor contributing to desiccation tolerance. Phylogenetic diversity of resurrection plants reflects the diversity of sugar metabolism in response to dehydration. Sugars, which accumulate during dehydration, have been shown to protect macromolecules and membranes and to scavenge reactive oxygen species. This review focuses on the performance of enzymes participating in sugar metabolism during dehydration stress. The relation between sugar metabolism and other biochemical activities is discussed and open questions as well as potential experimental approaches are proposed.

  10. Enzymes and Metabolites in Carbohydrate Metabolism of Desiccation Tolerant Plants

    PubMed Central

    Zhang, Qingwei; Song, Xiaomin; Bartels, Dorothea

    2016-01-01

    Resurrection plants can tolerate extreme water loss. Substantial sugar accumulation is a phenomenon in resurrection plants during dehydration. Sugars have been identified as one important factor contributing to desiccation tolerance. Phylogenetic diversity of resurrection plants reflects the diversity of sugar metabolism in response to dehydration. Sugars, which accumulate during dehydration, have been shown to protect macromolecules and membranes and to scavenge reactive oxygen species. This review focuses on the performance of enzymes participating in sugar metabolism during dehydration stress. The relation between sugar metabolism and other biochemical activities is discussed and open questions as well as potential experimental approaches are proposed. PMID:28248249

  11. Time course of the response of carbohydrate metabolism to unloading of the soleus

    NASA Technical Reports Server (NTRS)

    Henriksen, Erik J.; Tischler, Marc E.

    1988-01-01

    The time course of the response of carbohydrate metabolism to unloading was studied in the soleus muscle of rats subjected to tail-cast suspension. In the fresh soleus, 12 hours of unloading led to higher concentrations of glycogen and lower activity ratios of both glycogen synthase and glycogen phosphorylase. These changes were still evident on day three. Thereafter, the increased glycogen concentration apparently diminished the activity ratio of glycogen synthase, leading to a subsequent fall in the total glycogen content after day one. After 24 hours of unloading, when no significant atrophy was detectable, there was no differential response to insulin for in vitro glucose metabolism. On day three, the soleus atrophied significantly and displayed a greater sensitivity to insulin for most of these parameters compared to the weight-bearing control muscle. However, insulin sensitivity for glycogen synthesis was unchanged. These results showed that the increased sensitivity to insulin of the unloaded soleus is associated with the degree of muscle atrophy, likely due to an increased insulin binding capacity relative to muscle mass. This study also showed that insulin regulation of glucose uptake and of glycogen synthesis is affected differentially in the unloaded soleus muscle.

  12. Seasonal influences on carbohydrate metabolism in the CAM bromeliad Aechmea ‘Maya’: consequences for carbohydrate partitioning and growth

    PubMed Central

    Ceusters, Johan; Borland, Anne M.; Ceusters, Nathalie; Verdoodt, Veerle; Godts, Christof; De Proft, Maurice P.

    2010-01-01

    Background and Aims Photosynthetic plasticity in response to a range of environmental factors that include [CO2], water availability, light intensity and temperature, is ubiquitous among plants with crassulacean acid metabolism (CAM). The present study examined how seasonal changes in light availability, as experienced by greenhouse CAM crops in northern latitude regions, influence diel carboxylation patterns and impact on carbon gain and seasonal accumulation of biomass. Methods In the CAM bromeliad Aechmea ‘Maya’ integrated measurements of leaf gas exchange, diel metabolite dynamics (e.g. malate, soluble sugars and starch) and biomass accumulation were made four times a year, i.e. in winter, spring, summer and autumn. Key Results During the brighter seasons (spring and summer) daytime Phases II and IV were dominated by C4 carboxylation, whilst the higher diurnal uptake in the autumn and winter was characterized by equal contributions of both Rubisco and PEPC. As a consequence, net CO2 uptake showed a significant depression at the end of the day in the darker months when supplementary illumination was turned off. Remarkable seasonal consistency was found in the amount of storage reserves available for nocturnal carboxylation, a consequence of predominantly daytime export of carbohydrate in spring and summer whilst nocturnal export was the major sink for carbohydrate in autumn and winter. Conclusions Throughout the different seasons Aechmea ‘Maya’ showed considerable plasticity in the timing and magnitude of C3 and C4 carboxylation processes over the diel cycle. Under low PPFD (i.e. winter and autumn) it appears that there was a constraint on the amount of carbohydrate exported during the day in order to maintain a consistent pool of transient carbohydrate reserves. This gave remarkable seasonal consistency in the amount of storage reserves available at night, thereby optimizing biomass gain throughout the year. The data have important practical

  13. Differential expression of carbohydrate metabolism genes during bud dormancy changes in leafy spurge (Euphorbia esula)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Underground adventitious buds of leafy spurge undergo three well-defined phases of dormancy, para-, endo-, and ecodormancy, throughout the year. In this study, relationships between carbohydrate metabolism and bud dormancy were examined and real-time PCR was used to determine if shifts in carbohydra...

  14. Differential Expression of Carbohydrate Metabolism Genes Associated with Bud Dormancy Changes in Leafy Spurge (Euphorbia esula)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Underground adventitious buds of leafy spurge undergo three well-defined phases of dormancy, para-, endo-, and ecodormancy, throughout the year. In this study, relationships between carbohydrate metabolism and bud dormancy were examined and real-time PCR was used to determine if shifts in carbohydra...

  15. Exogenous Classic Phytohormones Have Limited Regulatory Effects on Fructan and Primary Carbohydrate Metabolism in Perennial Ryegrass (Lolium perenne L.).

    PubMed

    Gasperl, Anna; Morvan-Bertrand, Annette; Prud'homme, Marie-Pascale; van der Graaff, Eric; Roitsch, Thomas

    2015-01-01

    Fructans are polymers of fructose and one of the main constituents of water-soluble carbohydrates in forage grasses and cereal crops of temperate climates. Fructans are involved in cold and drought resistance, regrowth following defoliation and early spring growth, seed filling, have beneficial effects on human health and are used for industrial processes. Perennial ryegrass (Lolium perenne L.) serves as model species to study fructan metabolism. Fructan metabolism is under the control of both synthesis by fructosyltransferases (FTs) and breakdown through fructan exohydrolases (FEHs). The accumulation of fructans can be triggered by high sucrose levels and abiotic stress conditions such as drought and cold stress. However, detailed studies on the mechanisms involved in the regulation of fructan metabolism are scarce. Since different phytohormones, especially abscisic acid (ABA), are known to play an important role in abiotic stress responses, the possible short term regulation of the enzymes involved in fructan metabolism by the five classical phytohormones was investigated. Therefore, the activities of enzymes involved in fructan synthesis and breakdown, the expression levels for the corresponding genes and levels for water-soluble carbohydrates were determined following pulse treatments with ABA, auxin (AUX), ethylene (ET), gibberellic acid (GA), or kinetin (KIN). The most pronounced fast effects were a transient increase of FT activities by AUX, KIN, ABA, and ET, while minor effects were evident for 1-FEH activity with an increased activity in response to KIN and a decrease by GA. Fructan and sucrose levels were not affected. This observed discrepancy demonstrates the importance of determining enzyme activities to obtain insight into the physiological traits and ultimately the plant phenotype. The comparative analyses of activities for seven key enzymes of primary carbohydrate metabolism revealed no co-regulation between enzymes of the fructan and sucrose pool.

  16. Exogenous Classic Phytohormones Have Limited Regulatory Effects on Fructan and Primary Carbohydrate Metabolism in Perennial Ryegrass (Lolium perenne L.)

    PubMed Central

    Gasperl, Anna; Morvan-Bertrand, Annette; Prud'homme, Marie-Pascale; van der Graaff, Eric; Roitsch, Thomas

    2016-01-01

    Fructans are polymers of fructose and one of the main constituents of water-soluble carbohydrates in forage grasses and cereal crops of temperate climates. Fructans are involved in cold and drought resistance, regrowth following defoliation and early spring growth, seed filling, have beneficial effects on human health and are used for industrial processes. Perennial ryegrass (Lolium perenne L.) serves as model species to study fructan metabolism. Fructan metabolism is under the control of both synthesis by fructosyltransferases (FTs) and breakdown through fructan exohydrolases (FEHs). The accumulation of fructans can be triggered by high sucrose levels and abiotic stress conditions such as drought and cold stress. However, detailed studies on the mechanisms involved in the regulation of fructan metabolism are scarce. Since different phytohormones, especially abscisic acid (ABA), are known to play an important role in abiotic stress responses, the possible short term regulation of the enzymes involved in fructan metabolism by the five classical phytohormones was investigated. Therefore, the activities of enzymes involved in fructan synthesis and breakdown, the expression levels for the corresponding genes and levels for water-soluble carbohydrates were determined following pulse treatments with ABA, auxin (AUX), ethylene (ET), gibberellic acid (GA), or kinetin (KIN). The most pronounced fast effects were a transient increase of FT activities by AUX, KIN, ABA, and ET, while minor effects were evident for 1-FEH activity with an increased activity in response to KIN and a decrease by GA. Fructan and sucrose levels were not affected. This observed discrepancy demonstrates the importance of determining enzyme activities to obtain insight into the physiological traits and ultimately the plant phenotype. The comparative analyses of activities for seven key enzymes of primary carbohydrate metabolism revealed no co-regulation between enzymes of the fructan and sucrose pool

  17. Toxic influence of organophosphate, carbamate, and organochlorine pesticides on cellular metabolism of lipids, proteins, and carbohydrates: a systematic review.

    PubMed

    Karami-Mohajeri, Somayyeh; Abdollahi, Mohammad

    2011-09-01

    Pesticides, including organophosphate (OP), organochlorine (OC), and carbamate (CB) compounds, are widely used in agricultural and indoor purposes. OP and CB act as acetyl cholinesterase (AChE) inhibitors that affect lots of organs such as peripheral and central nervous systems, muscles, liver, pancreas, and brain, whereas OC are neurotoxic involved in alteration of ion channels. There are several reports about metabolic disorders, hyperglycemia, and also oxidative stress in acute and chronic exposures to pesticides that are linked with diabetes and other metabolic disorders. In this respect, there are several in vitro and in vivo but few clinical studies about mechanism underlying these effects. Bibliographic databases were searched for the years 1963-2010 and resulted in 1652 articles. After elimination of duplicates or irrelevant papers, 204 papers were included and reviewed. Results indicated that OP and CB impair the enzymatic pathways involved in metabolism of carbohydrates, fats and protein within cytoplasm, mitochondria, and proxisomes. It is believed that OP and CB show this effect through inhibition of AChE or affecting target organs directly. OC mostly affect lipid metabolism in the adipose tissues and change glucose pathway in other cells. As a shared mechanism, all OP, CB and OC induce cellular oxidative stress via affecting mitochondrial function and therefore disrupt neuronal and hormonal status of the body. Establishing proper epidemiological studies to explore exact relationships between exposure levels to these pesticides and rate of resulted metabolic disorders in human will be helpful.

  18. The effect of enteric galactose on neonatal canine carbohydrate metabolism

    SciTech Connect

    Kliegman, R.M.; Miettinen, E.L.; Kalhan, S.C.; Adam, P.A.

    1981-01-01

    Newborn pups were assigned to a fasting group or to a group receiving intravenous glucose alimentation. Glucose turnover was determined during steady state equilibration of simultaneously infused (6-/sup 3/H) glucose. Thereafter, pups from each group received 0.625 g/Kg of either oral (U-/sup 14/C) galactose or (U-/sup 14/C) glucose. In fasted or intravenously alimented pups enteric glucose resulted in a rapid and sustained elevation of blood glucose concentrations. Systemic appearance of /sup 14/C label from enteric glucose increased rapidly as did the enrichment of blood (/sup 14/C) glucose specific activity. In those pups given enteric galactose, blood glucose values were equivalent to that in the glucose fed groups, however /sup 14/C appearing in blood glucose and blood glucose specific activity was significantly lower. The peak values for rates of appearance and disappearance of systemic glucose were significantly lower in pups fed galactose than among pups fed glucose. Glucose clearance was also significantly lower in these pups despite equivalent plasma insulin responses. Among fasting pups hepatic glycogen content was significantly higher in those given either oral glucose or galactose when compared to a completely starved control group. In contrast, among alimented pups galactose administration significantly enhanced hepatic glycogen content compared to those fed glucose. In addition, hepatic glycogen synthase (glucose-6-phosphate independent) activity was increased only among alimented pups fed galactose when compared to completely fasted pups. In conclusion these data suggest that following gastrointestinal galactose administration, hepatic carbohydrate uptake is augmented while glycogen synthesis may be enhanced. Augmented glycogen synthesis following galactose administration may reflect alterations in hepatic glycogen synthase activity or enhanced hepatic carbohydrate uptake.

  19. Serum complexes of insulin-like growth factor-1 modulate skeletal integrity and carbohydrate metabolism

    PubMed Central

    Yakar, Shoshana; Rosen, Clifford J.; Bouxsein, Mary L.; Sun, Hui; Mejia, Wilson; Kawashima, Yuki; Wu, Yingjie; Emerton, Kelly; Williams, Valerie; Jepsen, Karl; Schaffler, Mitchell B.; Majeska, Robert J.; Gavrilova, Oksana; Gutierrez, Mariana; Hwang, David; Pennisi, Patricia; Frystyk, Jan; Boisclair, Yves; Pintar, John; Jasper, Héctor; Domene, Horacio; Cohen, Pinchas; Clemmons, David; LeRoith, Derek

    2009-01-01

    Serum insulin-like growth factor (IGF) -1 is secreted mainly by the liver and circulates bound to IGF-binding proteins (IGFBPs), either as binary complexes or ternary complexes with IGFBP-3 or IGFBP-5 and an acid-labile subunit (ALS). The purpose of this study was to genetically dissect the role of IGF-1 circulatory complexes in somatic growth, skeletal integrity, and metabolism. Phenotypic comparisons of controls and four mouse lines with genetic IGF-1 deficits—liver-specific IGF-1 deficiency (LID), ALS knockout (ALSKO), IGFBP-3 (BP3) knockout, and a triply deficient LID/ALSKO/BP3 line—produced several novel findings. 1) All deficient strains had decreased serum IGF-1 levels, but this neither predicted growth potential or skeletal integrity nor defined growth hormone secretion or metabolic abnormalities. 2) IGF-1 deficiency affected development of both cortical and trabecular bone differently, effects apparently dependent on the presence of different circulating IGF-1 complexes. 3) IGFBP-3 deficiency resulted in increased linear growth. In summary, each IGF-1 complex constituent appears to play a distinct role in determining skeletal phenotype, with different effects on cortical and trabecular bone compartments.—Yakar, S., Rosen, C. J., Bouxsein, M. L., Sun, H., Mejia, W., Kawashima, Y., Wu, Y., Emerton, K., Williams, V., Jepsen, K., Schaffler, M. B., Majeska, R. J., Gavrilova, O., Gutierrez, M., Hwang, D., Pennisi, P., Frystyk, J., Boisclair, Y., Pintar, J., Jasper, H., Domene, H., Cohen, P., Clemmons, D., LeRoith, D. Serum complexes of insulin-like growth factor-1 modulate skeletal integrity and carbohydrate metabolism. PMID:18952711

  20. Dietary obesity in rats: influence on carbohydrate metabolism.

    PubMed

    Schemmel, R; Hu, D; Mickelsen, O; Romsos, D R

    1982-02-01

    When male rats were fed a high diet from 3 to 20 weeks of age, they weighed 633 g which was 30% more than the animals fed a high glucose diet. Blood samples after a 16 to 18 hour fast, from the rats fed the high fat and high glucose diets contained, respectively: 130 +/- 11, 110 +/- 8 mg glucose/100 ml; 27 +/- 5, 24 +/- 3 microunits immunoreactive insulin (IRI)/ml; 791 +/- 58, 1104 +/- 179 meq nonesterified fatty acids (NEFA)/L. A tolerance test, by stomach tube, with 125 mg of glucose/100g body weight indicated that the rats fed the high fat diet had significantly higher mean plasma glucose concentrations, lower IRI responses and a lower leve of NEFA than rats fed a high glucose diet. Switching diets for 5 weeks resulted in body weights of about 600 g for both groups of rats. Those rats switched from the high fat to the high glucose diet did show an improved glucose tolerance, while the reverse was true of rats switched from the high carbohydrate to the high fat diet.

  1. Effects of Salt Stress on Carbohydrate Metabolism of Lactobacillus plantarum ATCC 14917.

    PubMed

    Wang, Pingping; Wu, Zhen; Wu, Jing; Pan, Daodong; Zeng, Xiaoqun; Cheng, Kemeng

    2016-10-01

    Lactic acid bacteria are widely used in fermented foods, especially cheese products. In this study, we observed the salt tolerance of Lactobacillus plantarum ATCC 14917 after exposure to different concentrations of NaCl in MRS medium. Quantitative proteomic profiles using two-dimensional electrophoresis identified 384 proteins, of which 26 were upregulated and 31 downregulated. Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry was then used to identify 11 proteins, of which three were linked to carbohydrate metabolism. The downregulation of carbamoyl phosphate synthase in carbohydrate metabolism revealed a bacterial regulation mechanism to save energy in order to survive during the salt tolerance. Other proteins were found involved in transcription-translation processes, fatty acid biosynthesis, and the primary metabolic process.

  2. Carbohydrate ingestion during prolonged high-intensity intermittent exercise: impact on affect and perceived exertion.

    PubMed

    Backhouse, S H; Ali, A; Biddle, S J H; Williams, C

    2007-10-01

    This study was designed to determine the effects of ingesting a carbohydrate (CHO) solution on affective states and rating of perceived exertion (RPE) during prolonged intermittent high-intensity exercise. Seventeen male soccer players completed a prolonged intermittent high-intensity exercise protocol for 90 min on two occasions, separated by at least 7 days. Participants consumed either a 6.4% CHO (0.6 g/kg body mass (BM)/h) or an artificially sweetened placebo (PLA) solution immediately before (8 mL/kg BM) and every 15 min (3 mL/kg BM) during exercise in a double-blind, counterbalanced design. Pleasure-displeasure, perceived activation, RPE and plasma glucose concentration was assessed. The results showed that compared with the CHO trial, perceived activation were lower in the placebo trial during the last 30 min of exercise and this was accompanied by lowered plasma glucose concentrations. In the CHO trial, RPE was maintained in the last 30 min of exercise but carried on increasing in the PLA trial. Therefore, CHO ingestion during prolonged high-intensity exercise appears to elicit an enhanced perceived activation profile that may impact upon task persistence and performance. This finding is in addition to the physiological and metabolic benefits of the exogenous energy supply.

  3. [Affective disorders: endocrine and metabolic comorbidities].

    PubMed

    Cermolacce, M; Belzeaux, R; Adida, M; Azorin, J-M

    2014-12-01

    Links between affective and endocrine-metabolic disorders are numerous and complex. In this review, we explore most frequent endocrine-metabolic comorbidities. On the one hand, these comorbidities imply numerous iatrogenic effects from antipsychotics (metabolic side-effects) or from lithium (endocrine side-effects). On the other hand, these comorbidities are also associated with affective disorders independently from medication. We will successively examine metabolic syndrome, glycemic disturbances, obesity and thyroid disorders among patients with affective disorders. Endocrinemetabolic comorbidities can be individually encountered, but can also be associated. Therefore, they substantially impact morbidity and mortality by increasing cardiovascular risk factors. Two distinct approaches give an account of processes involved in these comorbidities: common environmental factors (iatrogenic effects, lifestyle), and/or shared physiological vulnerabilities. In conclusion, we provide a synthesis of important results and recommendations related to endocrine-metabolic comorbidities in affective disorders : heavy influence on morbidity and mortality, undertreatment of somatic diseases, importance of endocrine and metabolic side effects from main mood stabilizers, impact from sex and age on the prevalence of comorbidities, influence from previous depressive episodes in bipolar disorders, and relevance of systematic screening for subclinical (biological) disturbances.

  4. Protective effects of L-arabinose in high-carbohydrate, high-fat diet-induced metabolic syndrome in rats

    PubMed Central

    Hao, Lei; Lu, Xiaoling; Sun, Min; Li, Kai; Shen, Lingmin; Wu, Tao

    2015-01-01

    Background L-Arabinose is a non-caloric sugar, which could affect glucose and lipid metabolism and suppress obesity. However, few reports have described the effect of L-arabinose in metabolic syndrome, a combination of medical disorders that increase the risk of diabetes and cardiovascular disease. Objective This study was conducted to explore the effects of L-arabinose in rats with metabolic syndrome induced by a high-carbohydrate, high-fat (HCHF) diet. Methods After the rat model for metabolic syndrome was successfully established, L-arabinose was administrated by oral gavage for 6 weeks. The biochemical index and histological analysis were measured, and the expression levels of genes related to fatty acid metabolism were analyzed using real-time PCR. Results Following treatment with L-arabinose, metabolic syndrome rats had an obvious reduction in body weight, systolic blood pressure, diastolic blood pressure, fasting blood glucose, triglycerides, total cholesterol, serum insulin, TNF-α, and leptin. Further study showed that treatment with L-arabinose significantly increased the expression of mRNA for hepatic CPT-1α and PDK4, but the expression of mRNA for hepatic ACCα was reduced. Conclusions This work suggests that L-arabinose could lower body weight, Lee's index, and visceral index and improve dyslipidemia, insulin resistance, inflammation, and viscera function, which indicate that it might be a promising candidate for therapies combating metabolic syndrome. PMID:26652604

  5. [Role of some central mechanisms of carbohydrate metabolism in premature newborns with hypoglycaemic episodes].

    PubMed

    Chekotun, T V

    2005-01-01

    Hormones of the fetoplacental system and neurohormones are very important in the processes of metabolic adaptation and carbohydrate metabolism in particular. The levels of prolactin and somatotropin were detected in blood plasma of newborns to study the role of neurohormones in the development of newborn hypoglycaemia. The level of prolactin was also measured in mothers' milk. According to the obtained data, children at early neonatal period have insufficient production of somatotropin. Hyperprolactinaemia is typical for newborns. It testifies that this hormone plays an important part in metabolic homeostasis.

  6. Alterations in carbohydrate metabolism and its regulation in PPARalpha null mouse hearts.

    PubMed

    Gélinas, Roselle; Labarthe, François; Bouchard, Bertrand; Mc Duff, Janie; Charron, Guy; Young, Martin E; Des Rosiers, Christine

    2008-04-01

    Although a shift from fatty acids (FAs) to carbohydrates (CHOs) is considered beneficial for the diseased heart, it is unclear why subjects with FA beta-oxidation defects are prone to cardiac decompensation under stress conditions. The present study investigated potential alterations in the myocardial utilization of CHOs for energy production and anaplerosis in 12-wk-old peroxisome proliferator-activating receptor-alpha (PPARalpha) null mice (a model of FA beta-oxidation defects). Carbon-13 methodology was used to assess substrate flux through energy-yielding pathways in hearts perfused ex vivo at two workloads with a physiological substrate mixture mimicking the fed state, and real-time RT-quantitative polymerase chain reaction was used to document the expression of selected metabolic genes. When compared with that from control C57BL/6 mice, isolated working hearts from PPARalpha null mice displayed an impaired capacity to withstand a rise in preload (mimicking an increased venous return as it occurs during exercise) as reflected by a 20% decline in the aortic flow rate. At the metabolic level, beyond the expected shift from FA (5-fold down) to CHO (1.5-fold up; P < 0.001) at both preloads, PPARalpha null hearts also displayed 1) a significantly greater contribution of exogenous lactate and glucose and/or glycogen (2-fold up) to endogenous pyruvate formation, whereas that of exogenous pyruvate remained unchanged and 2) marginal alterations in citric acid cycle-related parameters. The lactate production rate was the only measured parameter that was affected differently by preloads in control and PPARalpha null mouse hearts, suggesting a restricted reserve for the latter hearts to enhance glycolysis when the energy demand is increased. Alterations in the expression of some glycolysis-related genes suggest potential mechanisms involved in this defective CHO metabolism. Collectively, our data highlight the importance of metabolic alterations in CHO metabolism

  7. Effects of oral contraceptive agents and sex steroids on carbohydrate metabolism.

    PubMed

    Kalkhoff, R K

    1972-01-01

    The article offers a general interpretation of the influence of oral contraceptive agents on glucose tolerance, emphasizing comparisons of synthetic sex hormones. Although there are conflicting reports on steroid-induced diabetes in normal women, their glucose curves are often higher when under oral contraceptive treatment, suggesting that oral contraceptives may induce a form of subclinical diabetes melitus that is reversible. Evidence from diabetic women suggests definite deliterious effects from contraceptive administration. Estradiol, estriol, and estrone may improve glucose tolerance in nondiabetic women and reduce insulin requirements in diabetics. Progesterone has little effect on carbohydrate tolerance, as did synthetic progestin. Conjugated equine estrogens (equilenine or Premarin) may provoke mild to moderate deterioration of carbohydrate tolerance. Parenterally administered natural estrogens and orally administered synthetic derivatives appear to differ sharply in their effects. Sex hormones' effects on carbohydrate metabolism likely involve interactions with insulin and endogenous glucocorticoids.

  8. Effects of prepartum dietary carbohydrate source and monensin on periparturient metabolism and lactation in multiparous cows.

    PubMed

    Chung, Y-H; Pickett, M M; Cassidy, T W; Varga, G A

    2008-07-01

    Eighty-five multiparous Holstein cows were used in a completely randomized design with restrictions to evaluate the effects of prepartum carbohydrate (CHO) source and monensin on periparturient dry matter intake (DMI), blood parameters, and lactation performance of dairy cows. Dietary treatments were arranged in a 2 x 2 factorial arrangement with a conventional (CONV) dry cow diet and a nonforage fiber source (NFFS) dry cow diet not supplemented (-) or supplemented (+) with 330 mg/cow per d of monensin as a top dressing. The CONV diet contained 70% forage and the NFFS diet contained nonforage fiber sources such that 28% of the forage was replaced with cottonseed hulls and soyhulls. The experimental diets (CONV and NFFS) were fed throughout the entire dry period (for 60 d before parturition). Monensin was top dressed once daily starting 28 d (27 +/- 1.8 SD) before the expected calving date and continued until parturition. After parturition, all cows received the same lactating cow diet. During the last 28 d of gestation, cows receiving the NFFS diets prepartum had greater DMI (15.8 vs. 11.9 kg/d), DMI as a percentage of body weight (2.1 vs. 1.6% of body weight), plasma glucose (67.4 vs. 64.6 mg/dL), and serum insulin concentrations (0.59 vs. 0.45 ng/mL), and lower plasma nonesterified fatty acid concentrations (185 vs. 245 microEq/L) compared with cows receiving the CONV diets prepartum. Average milk production or composition during the first 56 d of lactation was not significantly affected by prepartum source of CHO, monensin, or their combination; however, there was a trend for the prepartum CHO source to affect milk production over time. Supplementation of monensin as a top dressing for 28 d prepartum had no effect on periparturient measurements. The prepartum diet did not affect postpartum DMI, blood glucose, nonesterified fatty acids, insulin concentrations, or liver triglyceride content. Results from this research demonstrated that partly replacing

  9. Effect of Waterlogging on Carbohydrate Metabolism and the Quality of Fiber in Cotton (Gossypium hirsutum L.)

    PubMed Central

    Kuai, Jie; Chen, Yinglong; Wang, Youhua; Meng, Yali; Chen, Binglin; Zhao, Wenqing; Zhou, Zhiguo

    2016-01-01

    Transient waterlogging occurs frequently in the Yangtze River and adversely affects cotton fiber quality. However, the carbohydrate metabolic mechanism that affects fiber quality after waterlogging remains undescribed. Here, the effects of five waterlogging levels (0, 3, 6, 9, and 12 days) were assessed during flowering and boll formation to characterize the carbohydrates, enzymes and genes that affect the fiber quality of cotton after waterlogging. The cellulose and sucrose contents of cotton fibers were significantly decreased after waterlogging for 6 (WL6), 9 (WL9), and 12 d (WL12), although these properties were unaffected after 3 (WL3) and 6 days at the fruiting branch 14–15 (FB14–15). Sucrose phosphate synthase (SPS) was the most sensitive to waterlogging among the enzymes tested. SPS activity was decreased by waterlogging at FB6–7, whereas it was significantly enhanced under WL3–6 at FB10–15. Waterlogging down-regulated the expression of fiber invertase at 10 days post anthesis (DPA), whereas that of expansin, β-1,4-glucanase and endoxyloglucan transferase (XET) was up-regulated with increasing waterlogging time. Increased mRNA levels and activities of fiber SuSy at each fruiting branch indicated that SuSy was the main enzyme responsible for sucrose degradation because it was markedly induced by waterlogging and was active even when waterlogging was discontinued. We therefore concluded that the reduction in fiber sucrose and down-regulation of invertase at 10 DPA led to a markedly shorter fiber length under conditions WL6–12. Significantly decreased fiber strength at FB6–11 for WL6–12 was the result of the inhibition of cellulose synthesis and the up-regulation of expansin, β-1,4-glucanase and XET, whereas fiber strength increased under WL3–6 at FB14–15 due to the increased cellulose content of the fibers. Most of the indictors tested revealed that WL6 resulted in the best compensatory performance, whereas exposure to waterlogged

  10. Pre-Workout Carbohydrate Supplementation does not Affect Measures of Selfassessed Vitality and Affect in College Swimmers.

    PubMed

    Hill, Kathleen M; Whitehead, James R; Goodwin, Janice K

    2011-01-01

    Beneficial effects of dietary carbohydrate (CHO) on physical and psychological parameters have been demonstrated in athletes. Because affect, or mood, can predict athletic performace, the main objective of this study was to determine the effect of pre-workout CHO on affect in swimmers. College swimmers (n = 37) participated in a randomized crossover experiment of the effects of a pre-workout CHO supplement on vitality and affect. Subjects consumed a CHO supplement or placebo for two days before morning practice. After each morning practice, swimmers completed measures of affect and feelings of vitality. Pearson correlations were performed to describe relationships among variables. Differences in means between the CHO and placebo conditions were determined by paired t-tests. Independent t-tests were used to determine differences in variables between the highest and lowest tertiles of breakfast consumption frequency. All statistical analyses were performed using SAS 9.1.3 (Cary, NC) and statistical signficance was set at α = 0.05. There were no significant differences in affect or feelings of vitality between the CHO supplement and placebo conditions (all p ≥ 0.15). Our results do not support a beneficial effect of CHO supplementation before morning swim practice on affect or feelings of vitality in swimmers. Key pointsPre-workout carbohydrate did not affect post-workout measures of vitality or affect in collegiate swimmers.Avoidance of feeling nauseous/ill' and 'lack of time' were the most frequent reasons reported by swimmers for forgoing breakfast before morning swim practice.A longer trial of carbohydrate supplementation is needed to verify if there is indeed no effect of pre-workout carbohydrate on post-workout measures of vitality or affect in swimmers.

  11. The ingestion of combined carbohydrates does not alter metabolic responses or performance capacity during soccer-specific exercise in the heat compared to ingestion of a single carbohydrate.

    PubMed

    Clarke, N D; Campbell, I T; Drust, B; Evans, L; Reilly, T; Maclaren, D P M

    2012-01-01

    This study was designed to investigate the effect of ingesting a glucose plus fructose solution on the metabolic responses to soccer-specific exercise in the heat and the impact on subsequent exercise capacity. Eleven male soccer players performed a 90 min soccer-specific protocol on three occasions. Either 3 ml · kg(-1) body mass of a solution containing glucose (1 g · min(-1) glucose) (GLU), or glucose (0.66 g · min(-1)) plus fructose (0.33 g · min(-1)) (MIX) or placebo (PLA) was consumed every 15 minutes. Respiratory measures were undertaken at 15-min intervals, blood samples were drawn at rest, half-time and on completion of the protocol, and muscle glycogen concentration was assessed pre- and post-exercise. Following the soccer-specific protocol the Cunningham and Faulkner test was performed. No significant differences in post-exercise muscle glycogen concentration (PLA, 62.99 ± 8.39 mmol · kg wet weight(-1); GLU 68.62 ± 2.70; mmol · kg wet weight(-1) and MIX 76.63 ± 6.92 mmol · kg wet weight(-1)) or exercise capacity (PLA, 73.62 ± 8.61 s; GLU, 77.11 ± 7.17 s; MIX, 83.04 ± 9.65 s) were observed between treatments (P > 0.05). However, total carbohydrate oxidation was significantly increased during MIX compared with PLA (P < 0.05). These results suggest that when ingested in moderate amounts, the type of carbohydrate does not influence metabolism during soccer-specific intermittent exercise or affect performance capacity after exercise in the heat.

  12. Interrelation between compensation of carbohydrate metabolism and severity of manifestations of oxidative stress in type II diabetes mellitus.

    PubMed

    Nedosugova, L V; Lankin, V Z; Balabolkin, M I; Konovalova, G G; Lisina, M O; Antonova, K V; Tikhaze, A K; Belenkov, Yu N

    2003-08-01

    Glycosylation end-products formed during diabetes mellitus promoted atherogenic oxidative modification of low-density lipoproteins. We evaluated the effects of compensation of carbohydrate metabolism and therapy with antioxidant probucol on parameters of free radical oxidation in patients with type II diabetes mellitus. Compensation of carbohydrate metabolism reduced manifestations of oxidative stress, which was manifested in accelerated enzymatic utilization of reactive oxygen species and lipid peroxides and decreased content of free radical oxidation products in low-density lipoproteins. In patients with type II diabetes mellitus combination therapy with antioxidant probucol decreased the severity of oxidative stress and stabilized carbohydrate metabolism without increasing the dose of hypoglycemic preparations.

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

    PubMed

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

    2015-10-15

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

  14. Teaching arrangements of carbohydrate metabolism in biochemistry curriculum in Peking University Health Science Center.

    PubMed

    Chen, Hao; Ni, Ju-Hua

    2013-01-01

    Biochemistry occupies a unique place in the medical school curricula, but the teaching of biochemistry presents certain challenges. One of these challenges is facilitating students' interest in and mastery of metabolism. The many pathways and modes of regulation can be overwhelming for students to learn and difficult for professors to teach in an engaging manner. The first chapter of the metabolism section in current Chinese biochemistry textbooks covers carbohydrate metabolism. Medical students usually complain about the difficulty of this subject. Here we discuss how to facilitate learning by rearranging the subjects in this introductory chapter of biochemical metabolism and to lay a solid foundation for future study. The strategy involves reorganizing the order in which subjects are taught from simple to complex and from short to long metabolic pathways. Most students taking the curriculum consider that the strategy engages their learning interests in biochemistry and enhances their learning outcomes.

  15. Quantification of hepatic carbohydrate metabolism in conscious mice using serial blood and urine spots.

    PubMed

    van Dijk, Theo H; Boer, Theo S; Havinga, Rick; Stellaard, Frans; Kuipers, Folkert; Reijngoud, Dirk-Jan

    2003-11-01

    In vivo studies of hepatic carbohydrate metabolism in (genetically modified) conscious mice are hampered by limitations of blood and urine sample sizes. We developed and validated methods to quantify stable isotope dilution and incorporation in small blood and urine samples spotted onto filter paper. Blood glucose and urinary paracetamol-glucuronic acid were extracted from filter paper spots reproducibly and with high yield. Fractional isotopomer distributions of glucose and paracetamol-glucuronic acid when extracted from filter paper spots were almost identical to those isolated from the original body fluids. Rates of infusion of labeled compounds could be adjusted without perturbing hepatic glucose metabolism. This approach was used in mice to find the optimal metabolic condition for the study of hepatic carbohydrate metabolism. In fed mice, no isotopic steady state was observed during a 6-h label-infusion experiment. In 9-h-fasted mice, isotopic steady state was reached after 3 h of label infusion and important parameters in hepatic glucose metabolism could be calculated. The rate of de novo glucose-6-phosphate synthesis was 143 +/- 17 micromol kg(-1) min(-1) and partitioning to plasma glucose was 79.0 +/- 5.2%. In 24-h-fasted mice, abrupt changes were noticed in whole body and in hepatic glucose metabolism at the end of the experiment.

  16. Comparative effects of different triazole compounds on growth, photosynthetic pigments and carbohydrate metabolism of Solenostemon rotundifolius.

    PubMed

    Kishorekumar, A; Jaleel, C Abdul; Manivannan, P; Sankar, B; Sridharan, R; Panneerselvam, R

    2007-11-15

    The effects of two triazole compounds, triadimefon and hexaconazole, on the growth and carbohydrate metabolism were studied in Solenostemon rotundifolius Poir., Morton plants under pot culture. Plants were treated with triadimefon at 15mg l(-1) and hexaconazole at 10mg l(-1) separately by soil drenching on 80, 110 and 140 days after planting (DAP). The plants were harvested randomly and growth parameters were studied on 90, 120 and 150 DAP for determining the effect of both the triazole on growth and chlorophyll pigments. These triazole compounds increased the chlorophyll pigments. However, both the treatments decreased the fresh and dry weights of shoot and leaf area. Both these triazole resulted in a marginal increase in starch content and decreased the sugar contents. The carbohydrate metabolizing enzymes alpha- and beta-amylase activities were reduced and invertase activity increased in S. rotundifolius under triadimefon and hexaconazole treatments.

  17. Metabolic effects of carbohydrate-copper interactions in swine

    SciTech Connect

    Scholfield, D.J.; Reiser, S.; Steele, N.; Darcey, S.; Richards, M.; Fields, M.; Smith, J.C.

    1986-03-01

    Inadequate dietary copper(Cu) is known to elicit several undesirable metabolic changes in humans and rats. Abnormal cardiac function, including sudden death is a common finding in copper deficient (CuD) rats, especially those fed diets with a high fructose (FR) content. Swine were chosen as the animal model for this project since their circulatory system is morphologically similar to that of humans. In an effort to further study these dietary effects 12 male and 12 female swine were randomly assigned to 4 groups of 6 pigs each and fed CuD and Cu supplemented (CuS) diets with 20% of calories from either FR or glucose (GL) for a period of 10 weeks. In agreement with data from recent experiments, CuD swine exhibited anemia, decreased ceruloplasmin, Cu-Zn superoxide dismutase and serum Cu; however, serum cholesterol and triglycerides decreased significantly when the animals were fed the CuD diets as compared to those fed CuS diets. Serum glutamic pyruvic transaminase (SGPT) activity was lowest for pigs fed the CuD FR diet compared to the CuS and CuD Gl groups during the study. SGPT activity usually increases when humans consume high FR diets. The results of these analyses indicate that swine are an acceptable model for the study of dietary CuD, although some indices give inverse results compared to those seen in rats and humans.

  18. Halobacterium saccharovorum sp. nov., a carbohydrate-metabolizing, extremely halophilic bacterium

    NASA Technical Reports Server (NTRS)

    Tomlinson, G. A.; Hochstein, L. I.

    1976-01-01

    The previously described extremely halophilic bacterium, strain M6, metabolizes a variety of carbohydrates with the production of acid. In addition, the organism produces nitrite (but no gas) from nitrate, is motile, and grows most rapidly at about 50 C. These characteristics distinguish it from all previously described halophilic bacteria in the genus Halobacterium. It is suggested that it be designated as a new species, Halobacterium saccharovorum.

  19. A meta-metabolome network of carbohydrate metabolism: interactions between gut microbiota and host.

    PubMed

    Ibrahim, Maziya; Anishetty, Sharmila

    2012-11-16

    With the current knowledge of the multitude of microbes that inhabit the human body, it is increasingly clear that they constitute an integral component of the host. The gut microbiota community is principally involved in the metabolism of dietary constituents such as carbohydrates which account for majority of the energy intake from diet. Diet has gained an important role in shaping the composition of gut inhabitants. The quantity and type of food consumed is recognized as a causal factor for metabolic disorders such as obesity and diabetes. Analysis of host-microbe interactions can thus contribute to the understanding of such metabolic disorders. In this study, data from Kyoto Encyclopedia of Genes and Genomes and Carbohydrate Active EnZYmes Database was utilized as a starting point. Enzyme information from the host Homo sapiens coupled with details of the three predominant phyla of gut bacteria, namely Firmicutes, Bacteroidetes and Actinobacteria were used in the creation of a comprehensive metabolic network, which we refer to as 'meta-metabolome'. This 'meta-metabolome' provides a perspective of the degree to which microbes influence carbohydrate metabolism, in conjunction with host specific enzymes. Analysis of reactions in the network reveals the amplification of monosaccharide content brought about by microbial enzyme activity. The framework outlined in this study provides a holistic approach to assess host-microbe symbiosis. It also provides us with a means of analyzing how diet can be modulated to provide beneficial effects to the host or how probiotics can potentially be used to relieve certain metabolic disorders.

  20. Carbohydrate metabolism in Archaea: current insights into unusual enzymes and pathways and their regulation.

    PubMed

    Bräsen, Christopher; Esser, Dominik; Rauch, Bernadette; Siebers, Bettina

    2014-03-01

    The metabolism of Archaea, the third domain of life, resembles in its complexity those of Bacteria and lower Eukarya. However, this metabolic complexity in Archaea is accompanied by the absence of many "classical" pathways, particularly in central carbohydrate metabolism. Instead, Archaea are characterized by the presence of unique, modified variants of classical pathways such as the Embden-Meyerhof-Parnas (EMP) pathway and the Entner-Doudoroff (ED) pathway. The pentose phosphate pathway is only partly present (if at all), and pentose degradation also significantly differs from that known for bacterial model organisms. These modifications are accompanied by the invention of "new," unusual enzymes which cause fundamental consequences for the underlying regulatory principles, and classical allosteric regulation sites well established in Bacteria and Eukarya are lost. The aim of this review is to present the current understanding of central carbohydrate metabolic pathways and their regulation in Archaea. In order to give an overview of their complexity, pathway modifications are discussed with respect to unusual archaeal biocatalysts, their structural and mechanistic characteristics, and their regulatory properties in comparison to their classic counterparts from Bacteria and Eukarya. Furthermore, an overview focusing on hexose metabolic, i.e., glycolytic as well as gluconeogenic, pathways identified in archaeal model organisms is given. Their energy gain is discussed, and new insights into different levels of regulation that have been observed so far, including the transcript and protein levels (e.g., gene regulation, known transcription regulators, and posttranslational modification via reversible protein phosphorylation), are presented.

  1. Dietary glucose stimulus at larval stage modifies the carbohydrate metabolic pathway in gilthead seabream (Sparus aurata) juveniles: An in vivo approach using (14)C-starch.

    PubMed

    Rocha, Filipa; Dias, Jorge; Geurden, Inge; Dinis, Maria Teresa; Panserat, Stephane; Engrola, Sofia

    2016-11-01

    The concept of nutritional programming was investigated in order to enhance the use of dietary carbohydrates in gilthead seabream juveniles. We assessed the long-term effects of high-glucose stimuli, exerted at the larval stage, on the growth performance, nutrient digestibility and metabolic utilization and gene expression of seabream juveniles, challenged with a high-carbohydrate intake. During early development, a group of larvae (control, CTRL) were kept under a rich-protein-lipid feeding regime whereas another group (GLU) was subjected to high-glucose stimuli, delivered intermittently over time. At juvenile stage, triplicate groups (IBW: 2.5g) from each fish nutritional background were fed a high-protein (59.4%) low-carbohydrate (2.0%) diet before being subjected to a low-protein (43.0%) high-carbohydrate (33.0%) dietary challenge for 36-days. Fish from both treatments increased by 8-fold their initial body weight, but neither growth rate, feed intake, feed and protein efficiency, nutrient retention (except lipids) nor whole-body composition were affected (P˃0.05) by fish early nutritional history. Nutrient digestibility was also similar among both groups. The metabolic fate of (14)C-starch and (14)C-amino acids tracers was estimated; GLU juveniles showed higher absorption of starch-derived glucose in the gut, suggesting an enhanced digestion of carbohydrates, while amino acid use was not affected. Moreover, glucose was less used for de novo synthesis of hepatic proteins and muscle glycogen from GLU fish (P<0.05). Our metabolic data suggests that the early glucose stimuli may alter carbohydrate utilization in seabream juveniles.

  2. [Carbohydrate metabolism parameters in the thick-billed murre (Uria lomvia) infested with Alcataenia armillaris (Cestoda: Dilepididae)].

    PubMed

    Kuklina, M M; Kuklin, V V

    2013-01-01

    Some aspects of carbohydrate metabolism in noninfested thick-billed murres (Uria lomvia) and those infested with the tapeworm Alcataenia armillaris (Cestoda: Dilepididae) are reported. The findings demonstrate that the intestinal invasion by A. armillaris causes a drop in the activity of digestive enzymes (glycosidases and sacharase) and decreases blood glucose levels and glycogen content in the liver. The main reasons underlying changes in avian carbohydrate metabolism in cestode invasion are suggested.

  3. Carbohydrate starvation causes a metabolically active but nonculturable state in Lactococcus lactis.

    PubMed

    Ganesan, Balasubramanian; Stuart, Mark R; Weimer, Bart C

    2007-04-01

    This study characterized the ability of lactococci to become nonculturable under carbohydrate starvation while maintaining metabolic activity. We determined the changes in physiological parameters and extracellular substrate levels of multiple lactococcal strains under a number of environmental conditions along with whole-genome expression profiles. Three distinct phases were observed, logarithmic growth, sugar exhaustion, and nonculturability. Shortly after carbohydrate starvation, each lactococcal strain lost the ability to form colonies on solid media but maintained an intact cell membrane and metabolic activity for over 3.5 years. ML3, a strain that metabolized lactose rapidly, reached nonculturability within 1 week. Strains that metabolized lactose slowly (SK11) or not at all (IL1403) required 1 to 3 months to become nonculturable. In all cases, the cells contained at least 100 pM of intracellular ATP after 6 months of starvation and remained at that level for the remainder of the study. Aminopeptidase and lipase/esterase activities decreased below detection limits during the nonculturable phase. During sugar exhaustion and entry into nonculturability, serine and methionine were produced, while glutamine and arginine were depleted from the medium. The cells retained the ability to transport amino acids via proton motive force and peptides via ATP-driven translocation. The addition of branched-chain amino acids to the culture medium resulted in increased intracellular ATP levels and new metabolic products, indicating that branched-chain amino acid catabolism resulted in energy and metabolic products to support survival during starvation. Gene expression analysis showed that the genes responsible for sugar metabolism were repressed as the cells entered nonculturability. The genes responsible for cell division were repressed, while autolysis and cell wall metabolism genes were induced neither at starvation nor during nonculturability. Taken together, these

  4. Carbohydrate Starvation Causes a Metabolically Active but Nonculturable State in Lactococcus lactis▿ † ‡

    PubMed Central

    Ganesan, Balasubramanian; Stuart, Mark R.; Weimer, Bart C.

    2007-01-01

    This study characterized the ability of lactococci to become nonculturable under carbohydrate starvation while maintaining metabolic activity. We determined the changes in physiological parameters and extracellular substrate levels of multiple lactococcal strains under a number of environmental conditions along with whole-genome expression profiles. Three distinct phases were observed, logarithmic growth, sugar exhaustion, and nonculturability. Shortly after carbohydrate starvation, each lactococcal strain lost the ability to form colonies on solid media but maintained an intact cell membrane and metabolic activity for over 3.5 years. ML3, a strain that metabolized lactose rapidly, reached nonculturability within 1 week. Strains that metabolized lactose slowly (SK11) or not at all (IL1403) required 1 to 3 months to become nonculturable. In all cases, the cells contained at least 100 pM of intracellular ATP after 6 months of starvation and remained at that level for the remainder of the study. Aminopeptidase and lipase/esterase activities decreased below detection limits during the nonculturable phase. During sugar exhaustion and entry into nonculturability, serine and methionine were produced, while glutamine and arginine were depleted from the medium. The cells retained the ability to transport amino acids via proton motive force and peptides via ATP-driven translocation. The addition of branched-chain amino acids to the culture medium resulted in increased intracellular ATP levels and new metabolic products, indicating that branched-chain amino acid catabolism resulted in energy and metabolic products to support survival during starvation. Gene expression analysis showed that the genes responsible for sugar metabolism were repressed as the cells entered nonculturability. The genes responsible for cell division were repressed, while autolysis and cell wall metabolism genes were induced neither at starvation nor during nonculturability. Taken together, these

  5. Effects of step-wise increases in dietary carbohydrate on circulating saturated Fatty acids and palmitoleic Acid in adults with metabolic syndrome.

    PubMed

    Volk, Brittanie M; Kunces, Laura J; Freidenreich, Daniel J; Kupchak, Brian R; Saenz, Catherine; Artistizabal, Juan C; Fernandez, Maria Luz; Bruno, Richard S; Maresh, Carl M; Kraemer, William J; Phinney, Stephen D; Volek, Jeff S

    2014-01-01

    Recent meta-analyses have found no association between heart disease and dietary saturated fat; however, higher proportions of plasma saturated fatty acids (SFA) predict greater risk for developing type-2 diabetes and heart disease. These observations suggest a disconnect between dietary saturated fat and plasma SFA, but few controlled feeding studies have specifically examined how varying saturated fat intake across a broad range affects circulating SFA levels. Sixteen adults with metabolic syndrome (age 44.9±9.9 yr, BMI 37.9±6.3 kg/m2) were fed six 3-wk diets that progressively increased carbohydrate (from 47 to 346 g/day) with concomitant decreases in total and saturated fat. Despite a distinct increase in saturated fat intake from baseline to the low-carbohydrate diet (46 to 84 g/day), and then a gradual decrease in saturated fat to 32 g/day at the highest carbohydrate phase, there were no significant changes in the proportion of total SFA in any plasma lipid fractions. Whereas plasma saturated fat remained relatively stable, the proportion of palmitoleic acid in plasma triglyceride and cholesteryl ester was significantly and uniformly reduced as carbohydrate intake decreased, and then gradually increased as dietary carbohydrate was re-introduced. The results show that dietary and plasma saturated fat are not related, and that increasing dietary carbohydrate across a range of intakes promotes incremental increases in plasma palmitoleic acid, a biomarker consistently associated with adverse health outcomes.

  6. Affective Disorders, Bone Metabolism, and Osteoporosis

    PubMed Central

    2013-01-01

    The nature of the relationship between affective disorders, bone mineral density (BMD), and bone metabolism is unresolved, although there is growing evidence that many medications used to treat affective disorders are associated with low BMD or alterations in neuroendocrine systems that influence bone turnover. The objective of this review is to describe the current evidence regarding the association of unipolar and bipolar depression with BMD and indicators of bone metabolism, and to explore potential mediating and confounding influences of those relationships. The majority of studies of unipolar depression and BMD indicate that depressive symptoms are associated with low BMD. In contrast, evidence regarding the relationship between bipolar depression and BMD is inconsistent. There is limited but suggestive evidence to support an association between affective disorders and some markers of bone turnover. Many medications used to treat affective disorders have effects on physiologic systems that influence bone metabolism, and these conditions are also associated with a range of health behaviors that can influence osteoporosis risk. Future research should focus on disentangling the pathways linking psychotropic medications and their clinical indications with BMD and fracture risk. PMID:23874147

  7. A method for (13)C-labeling of metabolic carbohydrates within French bean leaves (Phaseolus vulgaris L.) for decomposition studies in soils.

    PubMed

    Girardin, Cyril; Rasse, Daniel P; Biron, Philippe; Ghashghaie, Jaleh; Chenu, Claire

    2009-06-01

    The molecular composition of plant residues is suspected to largely govern the fate of their constitutive carbon (C) in soils. Labile compounds, such as metabolic carbohydrates, are affected differently from recalcitrant and structural compounds by soil-C stabilisation mechanisms. Producing (13)C-enriched plant residues with specifically labeled fractions would help us to investigate the fate in soils of the constitutive C of these compounds. The objective of the present research was to test (13)C pulse chase labeling as a method for specifically enriching the metabolic carbohydrate components of plant residues, i.e. soluble sugars and starch. Bean plants were exposed to a (13)CO(2)-enriched atmosphere for 0.5, 1, 2, 3 and 21 h. The major soluble sugars were then determined on water-soluble extracts, and starch on HCl-hydrolysable extracts. The results show a quick differential labeling between water-soluble and water-insoluble compounds. For both groups, (13)C-labeling increased linearly with time. The difference in delta(13)C signature between water-soluble and insoluble fractions was 7 per thousand after 0.5 h and 70 per thousand after 21 h. However, this clear isotopic contrast masked a substantial labeling variability within each fraction. By contrast, metabolic carbohydrates on the one hand (i.e. soluble sugars + starch) and other fractions (essentially cell wall components) on the other hand displayed quite homogeneous signatures within fractions, and a significant difference in labeling between fractions: delta(13)C = 414 +/- 3.7 per thousand and 56 +/- 5.5 per thousand, respectively. Thus, the technique generates labeled plant residues displaying contrasting (13)C-isotopic signatures between metabolic carbohydrates and other compounds, with homogenous signatures within each group. Metabolic carbohydrates being labile compounds, our findings suggest that the technique is particularly appropriate for investigating the effect of compound lability on the long

  8. The Drosophila NR4A Nuclear Receptor DHR38 Regulates Carbohydrate Metabolism and Glycogen Storage

    PubMed Central

    Ruaud, Anne-Françoise; Lam, Geanette; Thummel, Carl S.

    2011-01-01

    Animals balance nutrient storage and mobilization to maintain metabolic homeostasis, a process that is disrupted in metabolic diseases like obesity and diabetes. Here, we show that DHR38, the single fly ortholog of the mammalian nuclear receptor 4A family of nuclear receptors, regulates glycogen storage during the larval stages of Drosophila melanogaster. DHR38 is expressed and active in the gut and body wall of larvae, and its expression levels change in response to nutritional status. DHR38 null mutants have normal levels of glucose, trehalose (the major circulating form of sugar), and triacylglycerol but display reduced levels of glycogen in the body wall muscles, which constitute the primary storage site for carbohydrates. Microarray analysis reveals that many metabolic genes are mis-regulated in DHR38 mutants. These include phosphoglucomutase, which is required for glycogen synthesis, and the two genes that encode the digestive enzyme amylase, accounting for the reduced amylase enzyme activity seen in DHR38 mutant larvae. These studies demonstrate that a critical role of nuclear receptor 4A receptors in carbohydrate metabolism has been conserved through evolution and that nutritional regulation of DHR38 expression maintains the proper uptake and storage of glycogen during the growing larval stage of development. PMID:21084378

  9. Effect of the alpha-glucosidase inhibitor, bromoconduritol, on carbohydrate metabolism in the silverleaf whitefly, Bemisia argentifolii.

    PubMed

    Salvucci, M

    2000-11-01

    The involvement of alpha-glucosidase in the partitioning of ingested sucrose between excretion and incorporation was investigated in the silverleaf whitefly (Bemisia argentifolii). Approximately half of the alpha-glucosidase activity in adult whiteflies was soluble and the remainder was associated with membranes. In contrast, almost all of the trehalulose synthase was membrane-associated. Isoelectric focusing revealed that soluble and membrane-associated alpha-glucosidases were each composed of several isozymes in the pH 5 to 6.5 range, but the distribution of activity among the various isozymes was different. Bromoconduritol, an inhibitor of glucosidases, inhibited trehalulose synthase and alpha-glucosidase activities in whitefly extracts. Inhibition was greatest when bromoconduritol was incubated with extracts prior to the addition of sucrose, consistent with the irreversible nature of this inhibitor. Addition of bromoconduritol to artificial diets decreased the extractable trehalulose synthase and alpha-glucosidase activities by about 30 and 50%, respectively. Ingestion of bromoconduritol reduced the amount of carbohydrate excreted by about 80% without changing the distribution of the major honeydew sugars or causing an increase in the proportion of sucrose that was excreted. Ingestion of bromoconduritol did not affect respiration, the content and distribution of soluble carbohydrates in whitefly bodies, or the conversion of labeled sucrose into glucose, trehalose and isobemisiose. The results indicate that partitioning of ingested carbon between excretion and metabolism in whiteflies is highly regulated, probably involving multiple forms of alpha-glucosidase that facilitate a separation of the processes involved in the metabolic utilization of sucrose from those involved in excretion of excess carbohydrate. Arch. Insect Biochem. Physiol. 45:117-128, 2000. Published 2001 Wiley-Liss, Inc.

  10. High-fat/low-carbohydrate diets regulate glucose metabolism via a long-term transcriptional loop.

    PubMed

    Sparks, Lauren M; Xie, Hui; Koza, Robert A; Mynatt, Randall; Bray, George A; Smith, Steven R

    2006-11-01

    Insulin sensitivity is characterized by insulin-stimulated glucose metabolism in skeletal muscle. We hypothesized that carbohydrate metabolism and storage might be under transcriptional control. To test this hypothesis, we fed insulin-sensitive males (glucose disposal rate, 14.7 +/- 4.1 mg/kg fat-free mass [FFM] per minute) an isoenergetic high-fat/low-carbohydrate diet (HF/LCD) for 3 days with muscle biopsies before and after intervention. Oligonucleotide microarrays revealed a total of 369 genes of 18861 genes on the arrays were differentially regulated in response to diet (Bonferonni adjusted P < .01). A similar experiment was conducted in mice with a 3-week intervention using a control group and an HF/LCD group to offset the lack of a control group within the human cohort. As part of an analysis of results previously published from this data set, 7 genes in the carbohydrate metabolism pathway changed in response to the HF/LCD, and 3 genes were confirmed by quantitative reverse transcriptase-polymerase chain reaction: fructose-2,6-biphosphatase 3 (PFKFB3), pyruvate dehydrogenase kinase, isoenzyme 4 (PDK4), and glycogen synthase 1 (muscle). In a separate experiment, we fed C57Bl/6J mice an HF/LCD for 3 weeks and found that the same glucose metabolism genes were changed by approximately 70% on average. Fructose-2,6-biphosphatase 3 and pyruvate dehydrogenase kinase, isoenzyme 4 increased and glycogen synthase 1 (muscle) decreased. Combined, these results suggest a mechanism whereby HF/LCD regulates the genes necessary for glucose utilization and storage vis-á-vis transcriptional control.

  11. Lactobacillus acidophilus NCFM affects vitamin E acetate metabolism and intestinal bile acid signature in monocolonized mice.

    PubMed

    Roager, Henrik M; Sulek, Karolina; Skov, Kasper; Frandsen, Henrik L; Smedsgaard, Jørn; Wilcks, Andrea; Skov, Thomas H; Villas-Boas, Silas G; Licht, Tine R

    2014-01-01

    Monocolonization of germ-free (GF) mice enables the study of specific bacterial species in vivo. Lactobacillus acidophilus NCFM(TM) (NCFM) is a probiotic strain; however, many of the mechanisms behind its health-promoting effect remain unknown. Here, we studied the effects of NCFM on the metabolome of jejunum, cecum, and colon of NCFM monocolonized (MC) and GF mice using liquid chromatography coupled to mass-spectrometry (LC-MS). The study adds to existing evidence that NCFM in vivo affects the bile acid signature of mice, in particular by deconjugation. Furthermore, we confirmed that carbohydrate metabolism is affected by NCFM in the mouse intestine as especially the digestion of oligosaccharides (penta- and tetrasaccharides) was increased in MC mice. Additionally, levels of α-tocopherol acetate (vitamin E acetate) were higher in the intestine of GF mice than in MC mice, suggesting that NCFM affects the vitamin E acetate metabolism. NCFM did not digest vitamin E acetate in vitro, suggesting that direct bacterial metabolism was not the cause of the altered metabolome in vivo. Taken together, our results suggest that NCFM affects intestinal carbohydrate metabolism, bile acid metabolism and vitamin E metabolism, although it remains to be investigated whether this effect is unique to NCFM.

  12. Novel findings on the metabolic effects of the low glycaemic carbohydrate isomaltulose (Palatinose).

    PubMed

    Holub, Ines; Gostner, Andrea; Theis, Stephan; Nosek, Leszek; Kudlich, Theodor; Melcher, Ralph; Scheppach, W

    2010-06-01

    The slow digestible disaccharide isomaltulose (iso; Palatinose) is available as novel functional carbohydrate ingredient for manufacturing of low glycaemic foods and beverages. Although basically characterised, various information on physiological effects of iso are still lacking. Thus, the objective of the present study was to expand scientific knowledge of physiological characteristics of iso by a set of three human intervention trials. Using an ileostomy model, iso was found to be essentially absorbed, irrespective of the nature of food (beverage and solid food). Apparent digestibility of 50 g iso from two different meals was 95.5 and 98.8 %; apparent absorption was 93.6 and 96.1 %, respectively. In healthy volunteers, a single dose intake of iso resulted in lower postprandial blood glucose and insulin responses than did sucrose (suc), while showing prolonged blood glucose delivery over 3 h test. In a 4-week trial with hyperlipidaemic individuals, regular consumption of 50 g/d iso within a Western-type diet was well tolerated and did not affect blood lipids. Fasting blood glucose and insulin resistance were lower after the 4-week iso intervention compared with baseline. This would be consistent with possible beneficial metabolic effects as a consequence of the lower and prolonged glycaemic response and lower insulinaemic burden. However, there was no significant difference at 4 weeks after iso compared with suc. In conclusion, the study shows that iso is completely available from the small intestine, irrespective of food matrix, leading to a prolonged delivery of blood glucose. Regular iso consumption is well tolerated also in subjects with increased risk for vascular diseases.

  13. Novel findings on the metabolic effects of the low glycaemic carbohydrate isomaltulose (Palatinose™)

    PubMed Central

    Holub, Ines; Gostner, Andrea; Theis, Stephan; Nosek, Leszek; Kudlich, Theodor; Melcher, Ralph; Scheppach, W.

    2010-01-01

    The slow digestible disaccharide isomaltulose (iso; Palatinose™) is available as novel functional carbohydrate ingredient for manufacturing of low glycaemic foods and beverages. Although basically characterised, various information on physiological effects of iso are still lacking. Thus, the objective of the present study was to expand scientific knowledge of physiological characteristics of iso by a set of three human intervention trials. Using an ileostomy model, iso was found to be essentially absorbed, irrespective of the nature of food (beverage and solid food). Apparent digestibility of 50 g iso from two different meals was 95·5 and 98·8 %; apparent absorption was 93·6 and 96·1 %, respectively. In healthy volunteers, a single dose intake of iso resulted in lower postprandial blood glucose and insulin responses than did sucrose (suc), while showing prolonged blood glucose delivery over 3 h test. In a 4-week trial with hyperlipidaemic individuals, regular consumption of 50 g/d iso within a Western-type diet was well tolerated and did not affect blood lipids. Fasting blood glucose and insulin resistance were lower after the 4-week iso intervention compared with baseline. This would be consistent with possible beneficial metabolic effects as a consequence of the lower and prolonged glycaemic response and lower insulinaemic burden. However, there was no significant difference at 4 weeks after iso compared with suc. In conclusion, the study shows that iso is completely available from the small intestine, irrespective of food matrix, leading to a prolonged delivery of blood glucose. Regular iso consumption is well tolerated also in subjects with increased risk for vascular diseases. PMID:20211041

  14. The influence of altered gravity on carbohydrate metabolism in excised wheat leaves

    NASA Technical Reports Server (NTRS)

    Obenland, D. M.; Brown, C. S.

    1994-01-01

    We developed a system to study the influence of altered gravity on carbohydrate metabolism in excised wheat leaves by means of clinorotation. The use of excised leaves in our clinostat studies offered a number of advantages over the use of whole plants, most important of which were minimization of exogenous mechanical stress and a greater amount of carbohydrate accumulation during the time of treatment. We found that horizontal clinorotation of excised wheat leaves resulted in significant reductions in the accumulation of fructose, sucrose, starch and fructan relative to control, vertically clinorotated leaves. Photosynthesis, dark respiration and the extractable activities of ADP glucose pyrophosphorylase (EC 2.7.7.27), sucrose phosphate synthase (EC 2.4.4.14), sucrose sucrose fructosyltransferase (EC 2.4.1.99), and fructan hydrolase (EC 3.2.1.80) were unchanged due to altered gravity treatment.

  15. Effects of carbohydrate quantity and glycemic index on resting metabolic rate and body composition during weight loss

    PubMed Central

    Karl, J. Philip; Roberts, Susan B.; Schaefer, Ernst J.; Gleason, Joi A.; Fuss, Paul; Rasmussen, Helen; Saltzman, Edward; Das, Sai Krupa

    2015-01-01

    Objective To examine the effects of diets varying in carbohydrate and glycemic index (GI) on changes in body composition, resting metabolic rate (RMR) and metabolic adaptation during and after weight loss. Methods Adults with obesity (n = 91) were randomized to one of four provided-food diets for 17 wk. Diets differed in percentage energy from carbohydrate (55% or 70%) and GI (low or high), but were matched for protein, fiber and energy. Body weight, body composition, RMR, and metabolic adaptation (measured RMR – predicted RMR) were measured during weight loss and subsequent weight stability. Results No effect of dietary carbohydrate content or GI on body weight loss or percentage of weight lost as fat mass was observed. Measured RMR was significantly lower (−226 kJ/d [95%CI: −314 kJ/d, −138 kJ/d] P < 0.001) than predicted RMR following weight loss, but this difference was attenuated after 5 wk weight stability. Metabolic adaptation did not differ by dietary carbohydrate content or GI, and was not associated with weight regain 12 mo later. Conclusion Moderate-carbohydrate and low-GI diets did not preferentially reduce fat mass, preserve lean mass, or attenuate metabolic adaptation during weight loss compared to high-carbohydrate and high-GI diets. PMID:26530933

  16. Skeletal muscle glycogen concentration and metabolic responses following a high glycaemic carbohydrate breakfast.

    PubMed

    Chryssanthopoulos, Costas; Williams, Clyde; Nowitz, Andrea; Bogdanis, Gregory

    2004-01-01

    The purpose of this study was to examine the influence of a carbohydrate-rich meal on post-prandial metabolic responses and skeletal muscle glycogen concentration. After an overnight fast, eight male recreational/club endurance runners ingested a carbohydrate (CHO) meal (2.5 g CHO x kg(-1) body mass) and biopsies were obtained from the vastus lateralis muscle before and 3 h after the meal. Ingestion of the meal resulted in a 10.6 +/- 2.5% (P < 0.05) increase in muscle glycogen concentration (pre-meal vs post-meal: 314.0 +/- 33.9 vs 347.3 +/- 31.3 mmol x kg(-1) dry weight). Three hours after ingestion, mean serum insulin concentrations had not returned to pre-feeding values (0 min vs 180 min: 45 +/- 4 vs 143 +/- 21 pmol x l(-1)). On a separate occasion, six similar individuals ingested the meal or fasted for a further 3 h during which time expired air samples were collected to estimate the amount of carbohydrate oxidized over the 3 h post-prandial period. It was estimated that about 20% of the carbohydrate consumed was converted into muscle glycogen, and about 12 % was oxidized. We conclude that a meal providing 2.5 g CHO x kg(-1) body mass can increase muscle glycogen stores 3 h after ingestion. However, an estimated 67% of the carbohydrate ingested was unaccounted for and this may have been stored as liver glycogen and/or still be in the gastrointestinal tract.

  17. Improving students' understanding of carbohydrate metabolism in first-year biochemistry at tertiary level

    NASA Astrophysics Data System (ADS)

    Anderson, Trevor; Grayson, Diane

    1994-12-01

    Many introductory biochemistry students have problems understanding metabolism and acquiring the skills necessary to study metabolic pathways. In this paper we suggest that this may be largely due to the use of a traditional teaching approach which emphasises memorisation rather than understanding. We present an alternative approach to teaching carbohydrate metabolism which is designed to promote understanding of pathways. The approach also enables regular monitoring of, and reflection on, student progress and the identification of student reasoning and conceptual difficulties through the use of specially designed problems. Preliminary results are presented giving examples of specific student difficulties and the extent to which they were addressed by the alternative instructional approach. A qualitative evaluation of the approach is also presented.

  18. Protein v. carbohydrate intake differentially affects liking- and wanting-related brain signalling.

    PubMed

    Born, Jurriaan M; Martens, Mieke J I; Lemmens, Sofie G T; Goebel, Rainer; Westerterp-Plantenga, Margriet S

    2013-01-28

    Extreme macronutrient intakes possibly lead to different brain signalling. The aim of the present study was to determine the effects of ingesting high-protein v. high-carbohydrate food on liking and wanting task-related brain signalling (TRS) and subsequent macronutrient intake. A total of thirty female subjects (21.6 (SD 2.2) years, BMI 25.0 (SD 3.7) kg/m²) completed four functional MRI scans: two fasted and two satiated on two different days. During the scans, subjects rated all food items for liking and wanting, thereby choosing the subsequent meal. The results show that high-protein (PROT) v. high-carbohydrate (CARB) conditions were generated using protein or carbohydrate drinks at the first meal. Energy intake and hunger were recorded. PROT (protein: 53.7 (SD 2.1) percentage of energy (En%); carbohydrate: 6.4 (SD 1.3) En%) and CARB conditions (protein: 11.8 (SD 0.6) En%; carbohydrate: 70.0 (SD 2.4) En%) were achieved during the first meal, while the second meals were not different between the conditions. Hunger, energy intake, and behavioural liking and wanting ratings were decreased after the first meal (P< 0.001). Comparing the first with the second meal, the macronutrient content changed: carbohydrate -26.9 En% in the CARB condition, protein -37.8 En% in the PROT condition. After the first meal in the CARB condition, wanting TRS was increased in the hypothalamus. After the first meal in the PROT condition, liking TRS was decreased in the putamen (P< 0.05). The change in energy intake from the first to the second meal was inversely related to the change in liking TRS in the striatum and hypothalamus in the CARB condition and positively related in the PROT condition (P< 0.05). In conclusion, wanting and liking TRS were affected differentially with a change in carbohydrate or protein intake, underscoring subsequent energy intake and shift in macronutrient composition.

  19. Dietary carbohydrates, physical inactivity, obesity, and the 'metabolic syndrome' as predictors of coronary heart disease.

    PubMed

    Liu, S; Manson, J E

    2001-08-01

    Several decades of epidemiological and clinical research have identified physical inactivity, excessive calorie consumption, and excess weight as common risk factors for both type 2 diabetes mellitus and coronary heart disease. This trio forms the environmental substrate for a now well-recognized metabolic phenotype called the insulin resistance syndrome. Recent data suggest that a high intake of rapidly absorbed carbohydrates, which is characterized by a high glycemic load (a measure of carbohydrate quality and quantity), may increase the risk of coronary heart disease by aggravating glucose intolerance and dyslipidemia. These data also suggest that individuals who are obese and insulin resistant are particularly prone to the adverse effects of a high dietary glycemic load. In addition, data continue to accumulate suggesting the important beneficial effects of physical activity, even at moderate levels, and weight reduction on improving insulin sensitivity and reducing the risk of coronary heart disease. Future metabolic studies should continue to quantify the physiological impact of different foods on serum glucose and insulin, and such information should routinely be incorporated into large-scale and long-term prospective studies, in which the possible interaction effects between diet and other metabolic determinants such as physical activity and obesity can be examined. Until more definitive data are available, replacing refined grain products and potatoes with minimally processed plant-based foods such as whole grains, fruits, and vegetables, and reducing the intake of high glycemic load beverages may offer a simple strategy for reducing the incidence of coronary heart disease.

  20. Effects of training status on the metabolic responses to high carbohydrate and high fat meals.

    PubMed

    Bowden, V L; McMurray, R G

    2000-03-01

    The purpose of this study was to determine if there is a difference between the way in which aerobically trained and untrained women metabolize fats and carbohydrates at rest in response to either a high-fat or high-carbohydrate meal. Subjects, 6 per group, were fed a high CHO meal (2068 kJ, 76% CHO, 23% fat, 5% protein) and a high fat meal (2093 kJ, 21% CHO, 72% fat, 8% protein) in counterbalanced order. Resting metabolic rate (RMR) was measured every half-hour for 5 hours. RMR was similar between groups. However, after ingesting a high CHO meal, trained subjects had a peak in metabolism at minute 60, not evident in the untrained subjects. In addition, postprandial RER from minutes 120-300 were lower and fat use was greater after the high CHO meal for the trained subjects. These results suggest that aerobically trained women have an accelerated CHO uptake and overall lower CHO oxidation following the ingestion of a high CHO meal.

  1. Chemical reporter for visualizing metabolic cross-talk between carbohydrate metabolism and protein modification.

    PubMed

    Zaro, Balyn W; Chuh, Kelly N; Pratt, Matthew R

    2014-09-19

    Metabolic chemical reporters have been largely used to study posttranslational modifications. Generally, it was assumed that these reporters entered one biosynthetic pathway, resulting in labeling of one type of modification. However, because they are metabolized by cells before their addition onto proteins, metabolic chemical reporters potentially provide a unique opportunity to read-out on both modifications of interest and cellular metabolism. We report here the development of a metabolic chemical reporter 1-deoxy-N-pentynyl glucosamine (1-deoxy-GlcNAlk). This small-molecule cannot be incorporated into glycans; however, treatment of mammalian cells results in labeling of a variety proteins and enables their visualization and identification. Competition of this labeling with sodium acetate and an acetyltransferase inhibitor suggests that 1-deoxy-GlcNAlk can enter the protein acetylation pathway. These results demonstrate that metabolic chemical reporters have the potential to isolate and potentially discover cross-talk between metabolic pathways in living cells.

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

    PubMed

    Preisler, Nicolai; Laforet, Pascal; Madsen, Karen Lindhardt; Hansen, Regitze Sølling; Lukacs, Zoltan; Ørngreen, Mette Cathrine; Lacour, Arnaud; Vissing, John

    2012-11-01

    Pompe disease is caused by absence of the lysosomal enzyme acid alpha-glucosidase. It is generally assumed that intra-lysosomal hydrolysis of glycogen does not contribute to skeletal muscle energy production during exercise. However, this hypothesis has never been tested in vivo during exercise. We examined the metabolic response to exercise in patients with late-onset Pompe disease, in order to determine if a defect in energy metabolism may play a role in the pathogenesis of Pompe disease. We studied six adult patients with Pompe disease and 10 healthy subjects. The participants underwent ischemic forearm exercise testing, and peak work capacity was determined. Fat and carbohydrate metabolism during cycle exercise was examined with a combination of indirect calorimetry and stable isotope methodology. Finally, the effects of an IV glucose infusion on heart rate, ratings of perceived exertion, and work capacity during exercise were determined. We found that peak oxidative capacity was reduced in the patients to 17.6 vs. 38.8 ml kg(-1) min(-1) in healthy subjects (p = 0.002). There were no differences in the rate of appearance and rate of oxidation of palmitate, or total fat and carbohydrate oxidation, between the patients and the healthy subjects. None of the subjects improved exercise tolerance by IV glucose infusion. In conclusion, peak oxidative capacity is reduced in Pompe disease. However, skeletal muscle fat and carbohydrate use during exercise was normal. The results indicate that a reduced exercise capacity is caused by muscle weakness and wasting, rather than by an impaired skeletal muscle glycogenolytic capacity. Thus, it appears that acid alpha-glucosidase does not play a significant role in the production of energy in skeletal muscle during exercise.

  3. Effects of different carbohydrate sources on fructan metabolism in plants of Chrysolaena obovata grown in vitro

    PubMed Central

    Trevisan, Flavio; Oliveira, Vanessa F.; Carvalho, Maria A. M.; Gaspar, Marília

    2015-01-01

    Chrysolaena obovata (Less.) Dematt., previously named Vernonia herbacea, is an Asteraceae native to the Cerrado which accumulates about 80% of the rhizophore dry mass as inulin-type fructans. Considering its high inulin production and the wide application of fructans, a protocol for C. obovata in vitro culture was recently established. Carbohydrates are essential for in vitro growth and development of plants and can also act as signaling molecules involved in cellular adjustments and metabolic regulation. This work aimed to evaluate the effect of different sources of carbohydrate on fructan metabolism in plants grown in vitro. For this purpose, C. obovata plants cultivated in vitro were submitted to carbon deprivation and transferred to MS medium supplemented with sucrose, glucose or fructose. Following, their fructan composition and activity and expression of genes encoding enzymes for fructan synthesis (1-SST and 1-FFT) and degradation (1-FEH) were evaluated. For qRT-PCR analysis partial cDNA sequences corresponding to two different C. obovata genes, 1-SST and 1-FFT, were isolated. As expected, C. obovata sequences showed highest sequence identity to other Asteraceae 1-SST and 1-FFT, than to Poaceae related proteins. A carbon deficit treatment stimulated the transcription of the gene 1-FEH and inhibited 1-SST and 1-FFT and carbohydrate supplementation promoted reversal of the expression profile of these genes. With the exception of 1-FFT, a positive correlation between enzyme activity and gene expression was observed. The overall results indicate that sucrose, fructose and glucose act similarly on fructan metabolism and that 1-FEH and 1-SST are transcriptionally regulated by sugar in this species. Cultivation of plants in increasing sucrose concentrations stimulated synthesis and inhibited fructan mobilization, and induced a distinct pattern of enzyme activity for 1-SST and 1-FFT, indicating the existence of a mechanism for differential regulation between them

  4. Effects of different carbohydrate sources on fructan metabolism in plants of Chrysolaena obovata grown in vitro.

    PubMed

    Trevisan, Flavio; Oliveira, Vanessa F; Carvalho, Maria A M; Gaspar, Marília

    2015-01-01

    Chrysolaena obovata (Less.) Dematt., previously named Vernonia herbacea, is an Asteraceae native to the Cerrado which accumulates about 80% of the rhizophore dry mass as inulin-type fructans. Considering its high inulin production and the wide application of fructans, a protocol for C. obovata in vitro culture was recently established. Carbohydrates are essential for in vitro growth and development of plants and can also act as signaling molecules involved in cellular adjustments and metabolic regulation. This work aimed to evaluate the effect of different sources of carbohydrate on fructan metabolism in plants grown in vitro. For this purpose, C. obovata plants cultivated in vitro were submitted to carbon deprivation and transferred to MS medium supplemented with sucrose, glucose or fructose. Following, their fructan composition and activity and expression of genes encoding enzymes for fructan synthesis (1-SST and 1-FFT) and degradation (1-FEH) were evaluated. For qRT-PCR analysis partial cDNA sequences corresponding to two different C. obovata genes, 1-SST and 1-FFT, were isolated. As expected, C. obovata sequences showed highest sequence identity to other Asteraceae 1-SST and 1-FFT, than to Poaceae related proteins. A carbon deficit treatment stimulated the transcription of the gene 1-FEH and inhibited 1-SST and 1-FFT and carbohydrate supplementation promoted reversal of the expression profile of these genes. With the exception of 1-FFT, a positive correlation between enzyme activity and gene expression was observed. The overall results indicate that sucrose, fructose and glucose act similarly on fructan metabolism and that 1-FEH and 1-SST are transcriptionally regulated by sugar in this species. Cultivation of plants in increasing sucrose concentrations stimulated synthesis and inhibited fructan mobilization, and induced a distinct pattern of enzyme activity for 1-SST and 1-FFT, indicating the existence of a mechanism for differential regulation between them.

  5. beta-adrenergic effects on carbohydrate metabolism in the unweighted rat soleus muscle

    NASA Technical Reports Server (NTRS)

    Kirby, Christopher R.; Tischler, Marc E.

    1990-01-01

    The effect of unweighting on the response of the soleus-muscle carbohydrate metabolism to a beta-adrenergic agonist (isoproterenol) was investigated in rats that were subjected to three days of tail-cast suspension. It was found that isoproterenol promoted glycogen degradation in soleus from suspended rats to a higher degree than in weighted soleus from control rats, and had no effect in unweighted digitorum longus. However, isoproterenol did not have a greater inhibitory effect on the net uptake of tritium-labeled 2-deoxy-glucose by the unweighted soleus and that isoproterenol inhibited hexose phosphorylation less in the unweighted than in the control muscle.

  6. The effects of handling and anesthetic agents on the stress response and carbohydrate metabolism in northern elephant seals.

    PubMed

    Champagne, Cory D; Houser, Dorian S; Costa, Daniel P; Crocker, Daniel E

    2012-01-01

    Free-ranging animals often cope with fluctuating environmental conditions such as weather, food availability, predation risk, the requirements of breeding, and the influence of anthropogenic factors. Consequently, researchers are increasingly measuring stress markers, especially glucocorticoids, to understand stress, disturbance, and population health. Studying free-ranging animals, however, comes with numerous difficulties posed by environmental conditions and the particular characteristics of study species. Performing measurements under either physical restraint or chemical sedation may affect the physiological variable under investigation and lead to values that may not reflect the standard functional state of the animal. This study measured the stress response resulting from different handling conditions in northern elephant seals and any ensuing influences on carbohydrate metabolism. Endogenous glucose production (EGP) was measured using [6-(3)H]glucose and plasma cortisol concentration was measured from blood samples drawn during three-hour measurement intervals. These measurements were conducted in weanlings and yearlings with and without the use of chemical sedatives--under chemical sedation, physical restraint, or unrestrained. We compared these findings with measurements in adult seals sedated in the field. The method of handling had a significant influence on the stress response and carbohydrate metabolism. Physically restrained weanlings and yearlings transported to the lab had increased concentrations of circulating cortisol (F(11, 46) = 25.2, p<0.01) and epinephrine (F(3, 12) = 5.8, p = 0.01). Physical restraint led to increased EGP (t = 3.1, p = 0.04) and elevated plasma glucose levels (t = 8.2, p<0.01). Animals chemically sedated in the field typically did not exhibit a cortisol stress response. The combination of anesthetic agents (Telazol, ketamine, and diazepam) used in this study appeared to alleviate a cortisol stress

  7. The Effects of Handling and Anesthetic Agents on the Stress Response and Carbohydrate Metabolism in Northern Elephant Seals

    PubMed Central

    Champagne, Cory D.; Houser, Dorian S.; Costa, Daniel P.; Crocker, Daniel E.

    2012-01-01

    Free-ranging animals often cope with fluctuating environmental conditions such as weather, food availability, predation risk, the requirements of breeding, and the influence of anthropogenic factors. Consequently, researchers are increasingly measuring stress markers, especially glucocorticoids, to understand stress, disturbance, and population health. Studying free-ranging animals, however, comes with numerous difficulties posed by environmental conditions and the particular characteristics of study species. Performing measurements under either physical restraint or chemical sedation may affect the physiological variable under investigation and lead to values that may not reflect the standard functional state of the animal. This study measured the stress response resulting from different handling conditions in northern elephant seals and any ensuing influences on carbohydrate metabolism. Endogenous glucose production (EGP) was measured using [6-3H]glucose and plasma cortisol concentration was measured from blood samples drawn during three-hour measurement intervals. These measurements were conducted in weanlings and yearlings with and without the use of chemical sedatives—under chemical sedation, physical restraint, or unrestrained. We compared these findings with measurements in adult seals sedated in the field. The method of handling had a significant influence on the stress response and carbohydrate metabolism. Physically restrained weanlings and yearlings transported to the lab had increased concentrations of circulating cortisol (F11, 46 = 25.2, p<0.01) and epinephrine (F3, 12 = 5.8, p = 0.01). Physical restraint led to increased EGP (t = 3.1, p = 0.04) and elevated plasma glucose levels (t = 8.2, p<0.01). Animals chemically sedated in the field typically did not exhibit a cortisol stress response. The combination of anesthetic agents (Telazol, ketamine, and diazepam) used in this study appeared to alleviate a cortisol stress

  8. Carbohydrate Metabolism in Archaea: Current Insights into Unusual Enzymes and Pathways and Their Regulation

    PubMed Central

    Esser, Dominik; Rauch, Bernadette

    2014-01-01

    SUMMARY The metabolism of Archaea, the third domain of life, resembles in its complexity those of Bacteria and lower Eukarya. However, this metabolic complexity in Archaea is accompanied by the absence of many “classical” pathways, particularly in central carbohydrate metabolism. Instead, Archaea are characterized by the presence of unique, modified variants of classical pathways such as the Embden-Meyerhof-Parnas (EMP) pathway and the Entner-Doudoroff (ED) pathway. The pentose phosphate pathway is only partly present (if at all), and pentose degradation also significantly differs from that known for bacterial model organisms. These modifications are accompanied by the invention of “new,” unusual enzymes which cause fundamental consequences for the underlying regulatory principles, and classical allosteric regulation sites well established in Bacteria and Eukarya are lost. The aim of this review is to present the current understanding of central carbohydrate metabolic pathways and their regulation in Archaea. In order to give an overview of their complexity, pathway modifications are discussed with respect to unusual archaeal biocatalysts, their structural and mechanistic characteristics, and their regulatory properties in comparison to their classic counterparts from Bacteria and Eukarya. Furthermore, an overview focusing on hexose metabolic, i.e., glycolytic as well as gluconeogenic, pathways identified in archaeal model organisms is given. Their energy gain is discussed, and new insights into different levels of regulation that have been observed so far, including the transcript and protein levels (e.g., gene regulation, known transcription regulators, and posttranslational modification via reversible protein phosphorylation), are presented. PMID:24600042

  9. Effect of dietary fiber from banana (Musa paradisiaca) on metabolism of carbohydrates in rats fed cholesterol free diet.

    PubMed

    Usha, V; Vijayammal, P L; Kurup, P A

    1989-05-01

    Effect of feeding isolated dietary fiber from M. paradisiaca on the metabolism of carbohydrates in the liver has been studied. Fiber fed rats showed significantly lower levels of fasting blood glucose and higher concentration of liver glycogen. Activity of glycogen phosphorylase, glucose-1-phosphate, uridyl transferase and glycogen synthase was significantly higher while phosphoglucomutase activity showed lower activity. Activity of some glycolytic enzymes, viz. hexokinase and pyruvic kinase was lower. Glucose-6-phosphatase showed higher activity while fructose 1-6 diphosphatase activity was not affected. Glucose-6-phosphate dehydrogenase on the other hand showed higher activity. The changes in these enzyme activities have been attributed due to the effect of higher concentration of bile acids produced in the liver as a result of feeding fiber. Evidence for this has been obtained by studying the in vitro effect of cholic acid and chenodeoxy cholic acid.

  10. Gut carbohydrate metabolism instead of fat metabolism regulated by gut microbes mediates high-fat diet-induced obesity.

    PubMed

    Li, M; Gu, D; Xu, N; Lei, F; Du, L; Zhang, Y; Xie, W

    2014-09-01

    The aim of this study was to investigate the mechanisms underlying the involvement of gut microbes in body weight gain of high-fat diet-fed obesity-prone (obese) and obesity-resistant (lean) mice. C57BL/6 mice were grouped into an obese group, a lean group and a normal control group. Both obese and lean mice were fed a high-fat diet while normal control mice were fed a normal diet; they were observed for six weeks. The results showed that lean mice had lower serum lipid levels, body fat and weight gain than obese mice. The ATPase, succinate dehydrogenase and malate dehydrogenase activities in liver as well as oxygen expenditure and rectal temperature of lean mice were significantly lower than in obese mice. As compared with obese mice, the absorption of intestinal carbohydrates but not of fats or proteins was significantly attenuated in lean mice. Furthermore, 16S rRNA abundances of faecal Firmicutes and Bacteroidetes were significantly reduced in lean mice. In addition, faecal β-D-galactosidase activity and short chain fatty acid levels were significantly decreased in lean mice. Expressions of peroxisome proliferator-activated receptor gamma 2 and CCAAT/enhancer binding protein-β in visceral adipose tissues were significantly downregulated in lean mice as compared with obese mice. Resistance to dyslipidaemia and high-fat diet-induced obesity was mediated by ineffective absorption of intestinal carbohydrates but not of fats or proteins, probably through reducing gut Bacteroidetes and Firmicutes contents and lowering of gut carbohydrate metabolism. The regulation of intestinal carbohydrates instead of fat absorption by gut microbes might be a potential treatment strategy for high-fat diet-induced obesity.

  11. The Carbohydrate Metabolism Signature of Lactococcus lactis Strain A12 Reveals Its Sourdough Ecosystem Origin

    PubMed Central

    Passerini, Delphine; Coddeville, Michèle; Le Bourgeois, Pascal; Loubière, Pascal; Ritzenthaler, Paul; Fontagné-Faucher, Catherine; Cocaign-Bousquet, Muriel

    2013-01-01

    Lactococcus lactis subsp. lactis strain A12 was isolated from sourdough. Combined genomic, transcriptomic, and phenotypic analyses were performed to understand its survival capacity in the complex sourdough ecosystem and its role in the microbial community. The genome sequence comparison of strain A12 with strain IL1403 (a derivative of an industrial dairy strain) revealed 78 strain-specific regions representing 23% of the total genome size. Most of the strain-specific genes were involved in carbohydrate metabolism and are potentially required for its persistence in sourdough. Phenotype microarray, growth tests, and analysis of glycoside hydrolase content showed that strain A12 fermented plant-derived carbohydrates, such as arabinose and α-galactosides. Strain A12 exhibited specific growth rates on raffinose that were as high as they were on glucose and was able to release sucrose and galactose outside the cell, providing soluble carbohydrates for sourdough microflora. Transcriptomic analysis identified genes specifically induced during growth on raffinose and arabinose and reveals an alternative pathway for raffinose assimilation to that used by other lactococci. PMID:23872564

  12. Effect of training in the fasted state on metabolic responses during exercise with carbohydrate intake.

    PubMed

    De Bock, K; Derave, W; Eijnde, B O; Hesselink, M K; Koninckx, E; Rose, A J; Schrauwen, P; Bonen, A; Richter, E A; Hespel, P

    2008-04-01

    Skeletal muscle gene response to exercise depends on nutritional status during and after exercise, but it is unknown whether muscle adaptations to endurance training are affected by nutritional status during training sessions. Therefore, this study investigated the effect of an endurance training program (6 wk, 3 day/wk, 1-2 h, 75% of peak Vo(2)) in moderately active males. They trained in the fasted (F; n = 10) or carbohydrate-fed state (CHO; n = 10) while receiving a standardized diet [65 percent of total energy intake (En) from carbohydrates, 20%En fat, 15%En protein]. Before and after the training period, substrate use during a 2-h exercise bout was determined. During these experimental sessions, all subjects were in a fed condition and received extra carbohydrates (1 g.kg body wt(-1) .h(-1)). Peak Vo(2) (+7%), succinate dehydrogenase activity, GLUT4, and hexokinase II content were similarly increased between F and CHO. Fatty acid binding protein (FABPm) content increased significantly in F (P = 0.007). Intramyocellular triglyceride content (IMCL) remained unchanged in both groups. After training, pre-exercise glycogen content was higher in CHO (545 +/- 19 mmol/kg dry wt; P = 0.02), but not in F (434 +/- 32 mmol/kg dry wt; P = 0.23). For a given initial glycogen content, F blunted exercise-induced glycogen breakdown when compared with CHO (P = 0.04). Neither IMCL breakdown (P = 0.23) nor fat oxidation rates during exercise were altered by training. Thus short-term training elicits similar adaptations in peak Vo(2) whether carried out in the fasted or carbohydrate-fed state. Although there was a decrease in exercise-induced glycogen breakdown and an increase in proteins involved in fat handling after fasting training, fat oxidation during exercise with carbohydrate intake was not changed.

  13. Effects of Mixed Isoenergetic Meals on Fat and Carbohydrate Metabolism during Exercise in Older Men.

    PubMed

    Bassami, Minoo; Maclaren, Donald P M; Ahmadizad, Sajad; Doran, Dominic

    2011-01-01

    The present study was designed to investigate the effects of four different meals on fat and CHO metabolism during subsequent exercise in elderly males. Eight healthy males (age: 63.3 ± 5.2 years) reported to the physiology laboratory on four separate occasions, each of which was allocated for the performance of a 30-minute exercise on a cycle ergometer at 60% [Formula: see text] after having normal (N), high fat (HF), high carbohydrate high glycaemic index (HGI) and high carbohydrate low glycaemic index (LGI) meals. Fat oxidation during exercise after the meals (HF = 0.26 ± 0.04 g/min; N = 0.21 ± 0.04 g/min; HGI = 0.22 ± 0.03 g/min; LGI = 0.19 ± 0.03 g/min) was not significant (P > .05), and neither were the rates of carbohydrate oxidation (N = 1.79 ± 0.28, HF = 1.58 ± 0.22, HGI = 1.68 ± 0.22, and LGI = 1.77 ± 0.21 g/m). NEFA concentration increased after HF (P < .05) but decreased after HGI and LGI (P < .05). Glucose concentration decreased as a result of exercise after HF, and LGI (P < .05) whereas insulin concentration decreased significantly during exercise after N, HF, and HGI (P < .05). It can be concluded that, in elderly males, feeding isoenergetic meals containing different proportions of carbohydrate and fat do not significantly alter oxidation of fat and CHO during exercise in spite of changes in some circulating metabolites.

  14. The Role of Carbohydrate Response Element Binding Protein in Intestinal and Hepatic Fructose Metabolism

    PubMed Central

    Iizuka, Katsumi

    2017-01-01

    Many articles have discussed the relationship between fructose consumption and the incidence of obesity and related diseases. Fructose is absorbed in the intestine and metabolized in the liver to glucose, lactate, glycogen, and, to a lesser extent, lipids. Unabsorbed fructose causes bacterial fermentation, resulting in irritable bowl syndrome. Therefore, understanding the mechanisms underlying intestinal and hepatic fructose metabolism is important for the treatment of metabolic syndrome and fructose malabsorption. Carbohydrate response element binding protein (ChREBP) is a glucose-activated transcription factor that controls approximately 50% of de novo lipogenesis in the liver. ChREBP target genes are involved in glycolysis (Glut2, liver pyruvate kinase), fructolysis (Glut5, ketohexokinase), and lipogenesis (acetyl CoA carboxylase, fatty acid synthase). ChREBP gene deletion protects against high sucrose diet-induced and leptin-deficient obesity, because Chrebp−/− mice cannot consume fructose or sucrose. Moreover, ChREBP contributes to some of the physiological effects of fructose on sweet taste preference and glucose production through regulation of ChREBP target genes, such as fibroblast growth factor-21 and glucose-6-phosphatase catalytic subunits. Thus, ChREBP might play roles in fructose metabolism. Restriction of excess fructose intake will be beneficial for preventing not only metabolic syndrome but also irritable bowl syndrome. PMID:28241431

  15. The development of new molecular tools containing a chemically synthesized carbohydrate ligand for the elucidation of carbohydrate roles via photoaffinity labeling: carbohydrate-protein interactions are affected by the structures of the glycosidic bonds and the reducing-end sugar.

    PubMed

    Ohtsuka, Isao; Sadakane, Yutaka; Hada, Noriyasu; Higuchi, Mari; Atsumi, Toshiyuki; Kakiuchi, Nobuko

    2014-08-01

    Photoaffinity labeling technology is a highly efficient method for cloning carbohydrate-binding proteins. When the carbohydrate probes are synthesized according to conventional methods, however, the reducing terminus of the sugar is opened to provide an acyclic structure. Our continued efforts to solve this problem led to the development of new molecular tools with an oligosaccharide structure that contains a phenyldiazirine group for the elucidation of carbohydrate-protein interactions. We investigated whether carbohydrate-lectin interactions are affected by differences in the glycosidic formation and synthesized three types of molecular tools containing Galp-GlcpNAc disaccharide ligands and a photoreactive group (1, 2, 3). Photoaffinity labeling validated the recognition of the new ligand by different glycosidic bonds. Photoaffinity labeling also demonstrated that both the reducing end sugar and non-reducing end sugar recognized the Erythrina cristagalli agglutinin.

  16. The gut microbiome of kittens is affected by dietary protein:carbohydrate ratio and associated with blood metabolite and hormone concentrations.

    PubMed

    Hooda, Seema; Vester Boler, Brittany M; Kerr, Katherine R; Dowd, Scot E; Swanson, Kelly S

    2013-05-01

    High-protein, low-carbohydrate (HPLC) diets are common in cats, but their effect on the gut microbiome has been ignored. The present study was conducted to test the effects of dietary protein:carbohydrate ratio on the gut microbiota of growing kittens. Male domestic shorthair kittens were raised by mothers fed moderate-protein, moderate-carbohydrate (MPMC; n 7) or HPLC (n 7) diets, and then weaned at 8 weeks onto the same diet. Fresh faeces were collected at 8, 12 and 16 weeks; DNA was extracted, followed by amplification of the V4–V6 region of the 16S rRNA gene using 454 pyrosequencing. A total of 384 588 sequences (average of 9374 per sample) were generated. Dual hierarchical clustering indicated distinct clustering based on the protein:carbohydrate ratio regardless of age. The protein:carbohydrate ratio affected faecal bacteria. Faecal Actinobacteria were greater (P< 0·05) and Fusobacteria were lower (P< 0·05) in MPMC-fed kittens. Faecal Clostridium, Faecalibacterium, Ruminococcus, Blautia and Eubacterium were greater (P< 0·05) in HPLC-fed kittens, while Dialister, Acidaminococcus, Bifidobacterium, Megasphaera and Mitsuokella were greater (P< 0·05) in MPMC-fed kittens. Principal component analysis of faecal bacteria and blood metabolites and hormones resulted in distinct clusters. Of particular interest was the clustering of blood TAG with faecal Clostridiaceae, Eubacteriaceae, Ruminococcaceae, Fusobacteriaceae and Lachnospiraceae; blood ghrelin with faecal Coriobacteriaceae, Bifidobacteriaceae and Veillonellaceae; and blood glucose, cholesterol and leptin with faecal Lactobacillaceae. The present results demonstrate that the protein:carbohydrate ratio affects the faecal microbiome, and highlight the associations between faecal microbes and circulating hormones and metabolites that may be important in terms of satiety and host metabolism.

  17. Low humic acids promote in vitro lily bulblet enlargement by enhancing roots growth and carbohydrate metabolism * #

    PubMed Central

    Wu, Yun; Xia, Yi-ping; Zhang, Jia-ping; Du, Fang; Zhang, Lin; Ma, Yi-di; Zhou, Hong

    2016-01-01

    Bulblet development is a problem in global lily bulb production and carbohydrate metabolism is a crucial factor. Micropropagation acts as an efficient substitute for faster propagation and can provide a controllable condition to explore bulb growth. The present study was conducted to investigate the effects of humic acid (HA) on bulblet swelling and the carbohydrate metabolic pathway in Lilium Oriental Hybrids ‘Sorbonne’ under in vitro conditions. HA greatly promoted bulblet growth at 0.2, 2.0, and 20.0 mg/L, and pronounced increases in bulblet sucrose, total soluble sugar, and starch content were observed for higher HA concentrations (≥2.0 mg/L) within 45 d after transplanting (DAT). The activities of three major starch synthetic enzymes (including adenosine 5'-diphosphate glucose pyrophosphorylase, granule-bound starch synthase, and soluble starch synthase) were enhanced dramatically after HA application especially low concentration HA (LHA), indicating a quick response of starch metabolism. However, higher doses of HA also caused excessive aboveground biomass accumulation and inhibited root growth. Accordingly, an earlier carbon starvation emerged by observing evident starch degradation. Relative bulblet weight gradually decreased with increased HA doses and thereby broke the balance between the source and sink. A low HA concentration at 0.2 mg/L performed best in both root and bulblet growth. The number of roots and root length peaked at 14.5 and 5.75 cm, respectively. The fresh bulblet weight and diameter reached 468 mg (2.9 times that under the control treatment) and 11.68 mm, respectively. Further, sucrose/starch utilization and conversion were accelerated and carbon famine was delayed as a result with an average relative bulblet weight of 80.09%. To our knowledge, this is the first HA application and mechanism research into starch metabolism in both in vitro and in vivo condition in bulbous crops. PMID:27819136

  18. Chromium picolinate modulates serotonergic properties and carbohydrate metabolism in a rat model of diabetes.

    PubMed

    Komorowski, James R; Tuzcu, Mehmet; Sahin, Nurhan; Juturu, Vijaya; Orhan, Cemal; Ulas, Mustafa; Sahin, Kazim

    2012-10-01

    Chromium picolinate (CrPic) has shown both antidepressant and antidiabetic properties. In this study, the effects of CrPic on serotonergic properties and carbohydrate metabolism in diabetic rats were evaluated. Sixty male Sprague-Dawley rats were divided into four groups. (1) The control group received only standard diet (8 % fat). (2) The CrPic group was fed standard diet and CrPic (80 μg CrPic per kilogram body mass (b.m.)/day), for 10 weeks (microgram/kilogram b.m./day). (3) The HFD/STZ group fed a high-fat diet (HFD, 40 % fat) for 2 weeks and then received streptozotocin (STZ, 40 mg/kg, i.p.) (i.v.) HFD-STZ-CrPic group treated as the previous group and then were administered CrPic. CrPic administration to HFD/STZ-treated rats increased brain chromium levels and improved all measurements of carbohydrate metabolism and serotonergic properties (P<0.001). CrPic also significantly increased levels of insulin, tryptophan, and serotonin (P<0.001) in the serum and brain, and decreased cortisol levels in the serum (P<0.01). Except chromium levels, no significant effect of CrPic supplementation was detected on the overall measured parameters in the control group. CrPic administration was well tolerated without any adverse events. The results support the use of CrPic supplementation which improves serotonergic properties of brain in diabetes.

  19. Volatile organic compounds profile during milk fermentation by Lactobacillus pentosus and correlations between volatiles flavor and carbohydrate metabolism.

    PubMed

    Pan, D D; Wu, Z; Peng, T; Zeng, X Q; Li, H

    2014-02-01

    Flavor, as one of the most important properties determining the acceptability and preference of fermented milks, is influenced by compositional and processing factors. In this study, we focused on the volatile organic compounds related to flavor during milk fermentation by Lactobacillus pentosus according to electronic nose analysis. Xylose (1% addition) metabolized by Lb. pentosus strongly affects the flavor of yogurt, with the potent volatile organic compounds of ethanol (3.08%), 2,3-butanedione (7.77%), and acetic acid (22.70%) detected using solid-phase microextraction coupled with gas chromatography-mass spectrometry analysis. Sensoryanalysis also showed skimmed yogurt fermented by Lb. pentosus with 1% xylose had the unique scores of sourness (acetic acid) and butter flavor (2,3-butanedione). Furthermore, α-acetolactate synthase and α-acetolactate decarboxylase in carbohydrate metabolism play important roles in milk fermentation. Under preferable conditions (pH 5.5, 42 °C) for α-acetolactate synthase and α-acetolactate decarboxylase, the relative content of potent flavor compound 2,3-butanedione was 10.13%, which was 2.55% higher than common culture condition (pH 4.5, 37 °C), revealing that xylose metabolized by Lb. pentosus has potential values for the milk product industry, such as the acceptability and preference of fermented milk product.

  20. Insights into glycogen metabolism in Lactobacillus acidophilus: impact on carbohydrate metabolism, stress tolerance and gut retention.

    PubMed

    Goh, Yong Jun; Klaenhammer, Todd R

    2014-11-20

    In prokaryotic species equipped with glycogen metabolism machinery, the co-regulation of glycogen biosynthesis and degradation has been associated with the synthesis of energy storage compounds and various crucial physiological functions, including global cellular processes such as carbon and nitrogen metabolism, energy sensing and production, stress response and cell-cell communication. In addition, the glycogen metabolic pathway was proposed to serve as a carbon capacitor that regulates downstream carbon fluxes, and in some microorganisms the ability to synthesize intracellular glycogen has been implicated in host persistence. Among lactobacilli, complete glycogen metabolic pathway genes are present only in select species predominantly associated with mammalian hosts or natural environments. This observation highlights the potential involvement of glycogen biosynthesis in probiotic activities and persistence of intestinal lactobacilli in the human gastrointestinal tract. In this review, we summarize recent findings on (i) the presence and potential ecological distribution of glycogen metabolic pathways among lactobacilli, (ii) influence of carbon substrates and growth phases on glycogen metabolic gene expression and glycogen accumulation in L. acidophilus, and (iii) the involvement of glycogen metabolism on growth, sugar utilization and bile tolerance. Our present in vivo studies established the significance of glycogen biosynthesis on the competitive retention of L. acidophilus in the mouse intestinal tract, demonstrating for the first time that the ability to synthesize intracellular glycogen contributes to gut fitness and retention among probiotic microorganisms.

  1. Glucose metabolism and gene expression in juvenile zebrafish (Danio rerio) challenged with a high carbohydrate diet: effects of an acute glucose stimulus during late embryonic life.

    PubMed

    Rocha, Filipa; Dias, Jorge; Engrola, Sofia; Gavaia, Paulo; Geurden, Inge; Dinis, Maria Teresa; Panserat, Stephane

    2015-02-14

    Knowledge on the role of early nutritional stimuli as triggers of metabolic pathways in fish is extremely scarce. The objective of the present study was to assess the long-term effects of glucose injection in the yolk (early stimulus) on carbohydrate metabolism and gene regulation in zebrafish juveniles challenged with a high-carbohydrate low-protein (HC) diet. Eggs were microinjected at 1 d post-fertilisation (dpf) with either glucose (2 M) or saline solutions. Up to 25 dpf, fish were fed a low-carbohydrate high-protein (LC) control diet, which was followed by a challenge with the HC diet. Survival and growth of 35 dpf juveniles were not affected by injection or the HC diet. Glucose stimulus induced some long-term metabolic changes in the juveniles, as shown by the altered expression of genes involved in glucose metabolism. On glycolysis, the expression levels of hexokinase 1 (HK1) and phosphofructokinase-6 (6PFK) were up-regulated in the visceral and muscle tissues, respectively, of juveniles exposed to the glucose stimulus, indicating a possible improvement in glucose oxidation. On gluconeogenesis, the inhibition of the expression levels of PEPCK in fish injected with glucose suggested lower production of hepatic glucose. Unexpectedly, fructose-1,6-bisphosphatase (FBP) expression was induced and 6PFK expression reduced by glucose stimulus, leaving the possibility of a specific regulation of the FBP-6PFK metabolic cycle. Glucose metabolism in juveniles was estimated using a [¹⁴C]glucose tracer; fish previously exposed to the stimulus showed lower retention of [¹⁴C]glucose in visceral tissue (but not in muscle tissue) and, accordingly, higher glucose catabolism, in comparison with the saline group. Globally, our data suggest that glucose stimulus at embryo stage has the potential to alter particular steps of glucose metabolism in zebrafish juveniles.

  2. Effect of carbohydrate feeding on the bone metabolic response to running.

    PubMed

    Sale, Craig; Varley, Ian; Jones, Thomas W; James, Ruth M; Tang, Jonathan C Y; Fraser, William D; Greeves, Julie P

    2015-10-01

    Bone resorption is increased after running, with no change in bone formation. Feeding during exercise might attenuate this increase, preventing associated problems for bone. This study investigated the immediate and short-term bone metabolic responses to carbohydrate (CHO) feeding during treadmill running. Ten men completed two 7-day trials, once being fed CHO (8% glucose immediately before, every 20 min during, and immediately after exercise at a rate of 0.7 g CHO · kg body mass(-1) · h(-1)) and once being fed placebo (PBO). On day 4 of each trial, participants completed a 120-min treadmill run at 70% of maximal oxygen consumption (V̇o2 max). Blood was taken at baseline (BASE), immediately after exercise (EE), after 60 (R1) and 120 (R2) min of recovery, and on three follow-up days (FU1-FU3). Markers of bone resorption [COOH-terminal telopeptide region of collagen type 1 (β-CTX)] and formation [NH2-terminal propeptides of procollagen type 1 (P1NP)] were measured, along with osteocalcin (OC), parathyroid hormone (PTH), albumin-adjusted calcium (ACa), phosphate, glucagon-like peptide-2 (GLP-2), interleukin-6 (IL-6), insulin, cortisol, leptin, and osteoprotogerin (OPG). Area under the curve was calculated in terms of the immediate (BASE, EE, R1, and R2) and short-term (BASE, FU1, FU2, and FU3) responses to exercise. β-CTX, P1NP, and IL-6 responses to exercise were significantly lower in the immediate postexercise period with CHO feeding compared with PBO (β-CTX: P = 0.028; P1NP: P = 0.021; IL-6: P = 0.036), although there was no difference in the short-term response (β-CTX: P = 0.856; P1NP: P = 0.721; IL-6: P = 0.327). No other variable was significantly affected by CHO feeding during exercise. We conclude that CHO feeding during exercise attenuated the β-CTX and P1NP responses in the hours but not days following exercise, indicating an acute effect of CHO feeding on bone turnover.

  3. The skinny on low-carbohydrate diets: should they be recommended to patients with the metabolic syndrome?

    PubMed

    Stevens Ohlson, Melissa

    2006-01-01

    One in four adults living in the United States has metabolic syndrome, a constellation of risk factors associated with increased risk for developing type 2 diabetes and cardiovascular disease. A common characteristic in patients with metabolic syndrome is abdominal obesity along with an increased body mass index. Traditional dietary recommendations for treating the metabolic syndrome and associated obesity include high-carbohydrate, low-fat regimens. Despite the widespread use of these dietary guidelines, the rates of metabolic syndrome and obesity continue to rise in the United States. As a result, public interest in alternative dietary approaches to weight loss has escalated, sparking renewed interest in low-carbohydrate diet regimens, most notably Dr. Atkins' New Diet Revolution, a New York Times bestseller. Despite this renewed interest, there is little scientific evidence to determine the safety and efficacy of low-carbohydrate diets on cardiovascular health. Because most energy in a low-carbohydrate diet are derived from protein and fat, there is considerable concern that such diets will raise lipid levels and overall risk for coronary disease. In this article, we review the sparse literature on the impact of low-carbohydrate diets on weight loss and lipid parameters.

  4. Caffeine ingestion does not alter carbohydrate or fat metabolism in human skeletal muscle during exercise

    PubMed Central

    Graham, Terry E; Helge, Jorn W; MacLean, David A; Kiens, Bente; Richter, Erik A

    2000-01-01

    This study examined the effect of ingesting caffeine (6 mg kg−1) on muscle carbohydrate and fat metabolism during steady-state exercise in humans. Young male subjects (n = 10) performed 1 h of exercise (70 % maximal oxygen consumption (V̇O2,max)) on two occasions (after ingestion of placebo and caffeine) and leg metabolism was quantified by the combination of direct Fick measures and muscle biopsies. Following caffeine ingestion serum fatty acid and glycerol concentration increased (P ≤ 0.05) at rest, suggesting enhanced adipose tissue lipolysis. In addition circulating adrenaline concentration was increased (P ≤ 0.05) at rest following caffeine ingestion and this, as well as leg noradrenaline spillover, was elevated (P ≤ 0.05) above placebo values during exercise. Caffeine resulted in a modest increase (P ≤ 0.05) in leg vascular resistance, but no difference was found in leg blood flow. Arterial lactate and glucose concentrations were increased (P ≤ 0.05) by caffeine, while the rise in plasma potassium was dampened (P ≤ 0.05). There were no differences in respiratory exchange ratio or in leg glucose uptake, net muscle glycogenolysis, leg lactate release or muscle lactate, or glucose 6-phosphate concentration. Similarly there were no differences between treatments in leg fatty acid uptake, glycerol release or muscle acetyl CoA concentration. These findings indicate that caffeine ingestion stimulated the sympathetic nervous system but did not alter the carbohydrate or fat metabolism in the monitored leg. Other tissues must have been involved in the changes in circulating potassium, fatty acids, glucose and lactate. PMID:11118510

  5. Evaluation of endogenous acidic metabolic products associated with carbohydrate metabolism in tumor cells

    PubMed Central

    Mazzio, Elizabeth A.; Smith, Bruce

    2010-01-01

    Tumor cells have a high tolerance for acidic and hypoxic microenvironments, also producing abundant lactic acid through accelerated glycolysis in the presence or absence of O2. While the accumulation of lactate is thought to be a major contributor to the reduction of pH-circumscribing aggressive tumors, it is not known if other endogenous metabolic products contribute this acidity. Furthermore, anaerobic metabolism in cancer cells bears similarity to homo-fermentative lactic acid bacteria, however very little is known about an alternative pathway that may drive adenosine triphosphate (ATP) production independent of glycolysis. In this study, we quantify over 40 end-products (amines, acids, alcohols, aldehydes, or ketones) produced by malignant neuroblastoma under accelerated glycolysis (+glucose (GLU) supply 1–10 mM) ± mitochondrial toxin; 1-methyl-4-phenyl-pyridinium (MPP+) to abate aerobic respiration to delineate differences between anaerobic vs. aerobic cell required metabolic pathways. The data show that an acceleration of anaerobic glycolysis prompts an expected reduction in extracellular pH (pHex) from neutral to 6.7±0.006. Diverse metabolic acids associated with this drop in acidity were quantified by ionic exchange liquid chromatography (LC), showing concomitant rise in lactate (Ctrls 7.5±0.5 mM; +GLU 12.35±1.3 mM; +GLU + MPP 18.1±1.8 mM), acetate (Ctrl 0.84±0.13 mM: +GLU 1.3±0.15 mM; +GLU + MPP 2.7±0.4 mM), fumarate, and a-ketoglutarate (<10μM) while a range of other metabolic organic acids remained undetected. Amino acids quantified by o-phthalaldehyde precolumn derivatization/electrochemical detection–LC show accumulation of L-alanine (1.6±.052 mM), L-glutamate (285±9.7μM), L-asparagine (202±2.1μM), and L-aspartate (84.2±4.9μM) produced during routine metabolism, while other amino acids remain undetected. In contrast, the data show no evidence for accumulation of acetaldehyde, aldehydes, or ketones (Purpald/2

  6. Metabolic regulation of pathways of carbohydrate oxidation in potato (Solanum tuberosum) tubers.

    PubMed

    Centeno, Danilo C; Oliver, Sandra N; Nunes-Nesi, Adriano; Geigenberger, Peter; Machado, Daniel N; Loureiro, Marcelo Ehlers; Silva, Marco A P; Fernie, Alisdair R

    2008-08-01

    In the present article we evaluate the consequence of tuber-specific expression of yeast invertase, on the pathways of carbohydrate oxidation, in potato (Solanum tuberosum L. cv. Desiree). We analysed the relative rates of glycolysis and the oxidative pentose phosphate pathway that these lines exhibited as well as the relative contributions of the cytochrome and alternative pathways of mitochondrial respiration. Enzymatic and protein abundance analysis revealed concerted upregulation of the glycolytic pathway and of specific enzymes of the tricarboxylic acid cycle and the alternative oxidase but invariant levels of enzymes of the oxidative pentose phosphate pathway and proteins of the cytochrome pathway. When taken together these experiments suggest that the overexpression of a cytosolic invertase (EC 3.2.1.26) results in a general upregulation of carbohydrate oxidation with increased flux through both the glycolytic and oxidative pentose phosphate pathways as well as the cytochrome and alternative pathways of oxidative phosphorylation. Moreover these data suggest that the upregulation of respiration is a consequence of enhanced efficient mitochondrial metabolism.

  7. Effect of magnesium deficiency on lipid metabolism in rats fed a high carbohydrate diet.

    PubMed

    Rayssiguier, Y; Gueux, E; Weiser, D

    1981-11-01

    The effects of acute magnesium deficiency on lipid metabolism were examined in weaning rats fed a high carbohydrate diet containing starch or sucrose for 8 days. Rats were killed after the feeding period. In plasma, magnesium deficiency increased triglyceride and free cholesterol levels and decreased esterified cholesterol levels. Rats fed a magnesium-deficient diet containing sucrose showed particularly high triglyceride plasma levels. In liver, magnesium-deficient rats fed sucrose showed a significant increase in triglycerides, lactate and alpha-glycerophosphate and a significant decrease in glycogen. Changes in triglycerides and glycogen in the liver of magnesium-deficient rats fed starch were not significant. In sucrose-fed rats, serum lipoproteins were isolated by ultracentrifugation. With magnesium deficiency, triglycerides were significantly increased in the very low density lipoprotein (VLDL) and low density lipoprotein (LDL) fractions and cholesterol levels were increased in the VLDL and LDL and significantly lower in the high density lipoprotein (HDL) fractions. The detrimental effect of severe magnesium deficiency associated particularly with a high carbohydrate diet content and more especially with a sucrose diet is discussed.

  8. The transcriptome of Euglena gracilis reveals unexpected metabolic capabilities for carbohydrate and natural product biochemistry.

    PubMed

    O'Neill, Ellis C; Trick, Martin; Hill, Lionel; Rejzek, Martin; Dusi, Renata G; Hamilton, Chris J; Zimba, Paul V; Henrissat, Bernard; Field, Robert A

    2015-10-01

    Euglena gracilis is a highly complex alga belonging to the green plant line that shows characteristics of both plants and animals, while in evolutionary terms it is most closely related to the protozoan parasites Trypanosoma and Leishmania. This well-studied organism has long been known as a rich source of vitamins A, C and E, as well as amino acids that are essential for the human diet. Here we present de novo transcriptome sequencing and preliminary analysis, providing a basis for the molecular and functional genomics studies that will be required to direct metabolic engineering efforts aimed at enhancing the quality and quantity of high value products from E. gracilis. The transcriptome contains over 30,000 protein-encoding genes, supporting metabolic pathways for lipids, amino acids, carbohydrates and vitamins, along with capabilities for polyketide and non-ribosomal peptide biosynthesis. The metabolic and environmental robustness of Euglena is supported by a substantial capacity for responding to biotic and abiotic stress: it has the capacity to deploy three separate pathways for vitamin C (ascorbate) production, as well as producing vitamin E (α-tocopherol) and, in addition to glutathione, the redox-active thiols nor-trypanothione and ovothiol.

  9. [Effect of cadmium sulphate on the metabolism of carbohydrates in organism of rats of different ages].

    PubMed

    Shepel'ova, I A; Derkach, Ie A; Mel'nykova, N M

    2007-01-01

    The influence of cadmium sulfate on concentration of glucose, lactate, piruvate, alpha-ketoglutarate, malate, oxaloacetate in blood of 3-, 6- and 18-month-old poisoned rats was established the results of our researches. It was found, that poisoning of rats by cadmium sulfate causes the rise of concentration of glucose, metabolites of citric acid cycle and glycolysis in blood of animals of all age groups explored. The research results prove that in blood of 3-month-old poisoned rats the level of glycolysis and citric acid cycle activation is considerably higher in comparison with that of 6- and 18-month-old animals. As a result, a comparison of age-specific dynamics of changes of carbohydrate metabolism indices in the blood of rats, poisoned by cadmium showed that the organism of 3-month-old rats is more sensitive to toxic influence of cadmium.

  10. Carbohydrate metabolism and pathogenesis of diabetes mellitus in dogs and cats.

    PubMed

    Hoenig, Margarethe

    2014-01-01

    Diabetes mellitus (DM) is a common disease in dogs and cats and its prevalence is increasing in both species, probably due to an increase in obesity, although only in cats has obesity been clearly identified as a major risk factor for diabetes. While the classification of diabetes in dogs and cats has been modeled after that of humans, many aspects are different. Autoimmune destruction of beta cells, a feature of type 1 DM in people, is common in dogs; however, in contrast to what is seen in people, the disease occurs in older dogs. Diabetes also occurs in older cats but islet pathology in those species is characterized by the presence of amyloid, the hallmark of type 2 DM. Despite being overweight or obese, most naive diabetic cats, contrary to type 2 diabetic humans, present with low insulin concentrations. The physiology of carbohydrate metabolism and pathogenesis of diabetes, including histopathologic findings, in dogs and cats are discussed in this chapter.

  11. Chemical characterization, antioxidant and inhibitory effects of some marine sponges against carbohydrate metabolizing enzymes

    PubMed Central

    2012-01-01

    Background More than 15,000 marine products have been described up to now; Sponges are champion producers, concerning the diversity of products that have been found. Most bioactive compounds from sponges were classified into anti-inflammatory, antitumor, immuno- or neurosurpressive, antiviral, antimalarial, antibiotic, or antifouling. Evaluation of in vitro inhibitory effects of different extracts from four marine sponges versus some antioxidants indices and carbohydrate hydrolyzing enzymes concerned with diabetes mellitus was studied. The chemical characterizations for the extracts of the predominating sponges; SP1 and SP3 were discussed. Methods All chemicals served in the biological study were of analytical grade and purchased from Sigma, Merck and Aldrich. All kits were the products of Biosystems (Spain), Sigma Chemical Company (USA), Biodiagnostic (Egypt). Carbohydrate metabolizing enzymes; α-amylase, α-glucosidase, and β-galactosidase (EC3.2.1.1, EC3.2.1.20, and EC3.2.1.23, respectively) were obtained from Sigma Chemical Company (USA). Results Four marine sponges; Smenospongia (SP1), Callyspongia (SP2), Niphates (SP3), and Stylissa (SP4), were collected from the Red Sea at Egyptian coasts, and taxonomically characterized. The sponges' extracts exhibited diverse inhibitory effects on oxidative stress indices and carbohydrate hydrolyzing enzymes in linear relationships to some extent with concentration of inhibitors (dose dependant). The extracts of sponges (3, 1, and 2) showed, respectively, potent-reducing power. Purification and Chemical characterization of sponge 1 using NMR and mass spectroscopy, recognized the existence of di-isobutyl phthalate (1), di-n-butyl phthalate (2), linoleic acid (3), β-sitosterol (4), and cholesterol (5). Sponge 3 produced bis-[2-ethyl]-hexyl-phthylester (6) and triglyceride fatty acid ester (7). Conclusion Marine sponges are promising sources for delivering of bioactive compounds. Four marine sponges, collected from

  12. Alcoholic leaf extract of Plectranthus amboinicus regulates carbohydrate metabolism in alloxan-induced diabetic rats

    PubMed Central

    Koti, B. C.; Gore, Aparna; Thippeswamy, A. H. M.; Swamy, A. H. M. Viswanatha; Kulkarni, Rucha

    2011-01-01

    Objective: The present investigation was undertaken to explore the possible mechanisms of Plectranthus amboinicus leaf extract in alloxan-induced diabetic rats. Materials and Methods: Control and alloxan-induced diabetic albino rats received different treatments; orally control (vehicle), 200 mg/kg and 400 mg/kg of ethanol extract of Plectranthus amboinicus (PAEE) and 600 μg/kg of glibenclamide (standard) for 15 days. At the end of the experiment, the animals were sacrificed and enzyme activities of carbohydrate metabolism were measured in the liver. Results: Diabetic control rats showed a significant elevation (P < 0.001) in fasting blood glucose on successive days of the experiment as compared with their basal values, which was maintained over a period of 2 weeks. Daily oral treatment with PAEE showed a significant reduction (P < 0.001) in the blood glucose levels on successive days of the experiment as compared with their basal values. The most pronounced antihyperglycemic effect was obtained with the dose of 400 mg/kg. PAEE shows a dose-dependent reduction in gluconeogenic enzymes like glucose-6-phosphatase and fructose-1,6-disphosphatase. After 15 days of treatment with PAEE, glycolytic enzymes like phosphoglucoisomerase resulted in a significant increase with a concomitant significant decrease in the activities of aldolase. On the other hand, glucose-6-phosphate dehydrogenase was significantly improved in diabetic rats on administration of PAEE; the 400 mg/kg dose of PAEE elicited a more potent effect compared with the 200 mg/kg dose. Conclusion: The results obtained in this study provide evidence of the antidiabetic activity of PAEE, mediated through the regulation of carbohydrate metabolic enzyme activities. PMID:21713092

  13. Effects of heat stress on carbohydrate and lipid metabolism in growing pigs

    PubMed Central

    Victoria Sanz Fernandez, M; Johnson, Jay S; Abuajamieh, Mohannad; Stoakes, Sara K; Seibert, Jacob T; Cox, Lindsay; Kahl, Stanislaw; Elsasser, Theodore H; Ross, Jason W; Clay Isom, S; Rhoads, Robert P; Baumgard, Lance H

    2015-01-01

    Heat stress (HS) jeopardizes human and animal health and reduces animal agriculture productivity; however, its pathophysiology is not well understood. Study objectives were to evaluate the direct effects of HS on carbohydrate and lipid metabolism. Female pigs (57 ± 5 kg body weight) were subjected to two experimental periods. During period 1, all pigs remained in thermoneutral conditions (TN; 20°C) and were ad libitum fed. During period 2, pigs were exposed to: (1) constant HS conditions (32°C) and fed ad libitum (n = 7), or (2) TN conditions and pair-fed (PFTN; n = 10) to minimize the confounding effects of dissimilar feed intake. All pigs received an intravenous glucose tolerance test (GTT) and an epinephrine challenge (EC) in period 1, and during the early and late phases of period 2. After 8 days of environmental exposure, all pigs were killed and tissue samples were collected. Despite a similar reduction in feed intake (39%), HS pigs tended to have decreased circulating nonesterified fatty acids (NEFA; 20%) and a blunted NEFA response (71%) to the EC compared to PFTN pigs. During early exposure, HS increased basal circulating C-peptide (55%) and decreased the insulinogenic index (45%) in response to the GTT. Heat-stressed pigs had a reduced T3 to T4 ratio (56%) and hepatic 5′-deiodinase activity (58%). After 8 days, HS decreased or tended to decrease the expression of genes involved in oxidative phosphorylation in liver and skeletal muscle, and ATGL in adipose tissue. In summary, HS markedly alters both lipid and carbohydrate metabolism independently of nutrient intake. PMID:25716927

  14. Analysis of Anoxybacillus Genomes from the Aspects of Lifestyle Adaptations, Prophage Diversity, and Carbohydrate Metabolism

    PubMed Central

    Goh, Kian Mau; Gan, Han Ming; Chan, Kok-Gan; Chan, Giek Far; Shahar, Saleha; Chong, Chun Shiong; Kahar, Ummirul Mukminin; Chai, Kian Piaw

    2014-01-01

    Species of Anoxybacillus are widespread in geothermal springs, manure, and milk-processing plants. The genus is composed of 22 species and two subspecies, but the relationship between its lifestyle and genome is little understood. In this study, two high-quality draft genomes were generated from Anoxybacillus spp. SK3-4 and DT3-1, isolated from Malaysian hot springs. De novo assembly and annotation were performed, followed by comparative genome analysis with the complete genome of Anoxybacillus flavithermus WK1 and two additional draft genomes, of A. flavithermus TNO-09.006 and A. kamchatkensis G10. The genomes of Anoxybacillus spp. are among the smaller of the family Bacillaceae. Despite having smaller genomes, their essential genes related to lifestyle adaptations at elevated temperature, extreme pH, and protection against ultraviolet are complete. Due to the presence of various competence proteins, Anoxybacillus spp. SK3-4 and DT3-1 are able to take up foreign DNA fragments, and some of these transferred genes are important for the survival of the cells. The analysis of intact putative prophage genomes shows that they are highly diversified. Based on the genome analysis using SEED, many of the annotated sequences are involved in carbohydrate metabolism. The presence of glycosyl hydrolases among the Anoxybacillus spp. was compared, and the potential applications of these unexplored enzymes are suggested here. This is the first study that compares Anoxybacillus genomes from the aspect of lifestyle adaptations, the capacity for horizontal gene transfer, and carbohydrate metabolism. PMID:24603481

  15. High carbohydrate intake from starchy foods is positively associated with metabolic disorders: a Cohort Study from a Chinese population

    PubMed Central

    Feng, Rennan; Du, Shanshan; Chen, Yang; Zheng, Sining; Zhang, Wei; Na, Guanqiong; Li, Ying; Sun, Changhao

    2015-01-01

    Starchy foods are the main sources of carbohydrates; however, there is limited information on their metabolic impact. Therefore, we assessed the association between carbohydrates from starchy foods (Carb-S) intakes and the metabolic disorders of metabolic syndrome (MetS) and hyperlipidemia. In this study, 4,154 participants from Northern China were followed up for 4.2 years. Carb-S included rice, refined wheat, tubers, and their products. Multivariable regression models were used to calculate risk ratios (RRs) for MetS and hyperlipidemia from Carb-S, total carbohydrates, and carbohydrates from other food sources (Carb-O). Receiver operating characteristic analysis was used to determine a Carb-S cut-off value. High total carbohydrate intake was associated with increased risks of MetS (RR: 2.24, 95% CI: 1.00–5.03) and hyperlipidemia (RR: 3.05, 95% CI: 1.25–7.45), compared with the first quartile. High Carb-S intake (fourth quartile) was significantly associated with MetS (RR: 1.48, 95% CI: 1.01–2.69) and hyperlipidemia (RR: 1.73, 95% CI: 1.05–3.35). No associations with Carb-O were observed. Visceral adiposity, triglyceride levels, and high-density lipoprotein cholesterol significantly contributed to the metabolic disorders. The Carb-S cut-off value was 220 g. Both high total carbohydrate and Carb-S intakes were associated with hyperlipidemia and MetS; Carb-S appears to contribute more to these disorders. PMID:26581652

  16. Maternal metabolic stress may affect oviduct gatekeeper function.

    PubMed

    Jordaens, Lies; Van Hoeck, Veerle; Maillo, Veronica; Gutierrez-Adan, Alfonso; Marei, Waleed Fawzy A; Vlaeminck, Bruno; Thys, Sofie; Sturmey, Roger G S; Bols, Peter; Leroy, Jo

    2017-03-03

    We hypothesized that elevated non-esterified fatty acids (NEFA) modify in vitro bovine oviduct epithelial cell (BOEC) metabolism and barrier function. Hereto, BOECs were studied in a polarized system with 24h-treatments at day 9: 1) CONTROL (0µM NEFA + 0%EtOH), 2) SOLVENT CONTROL (0µM NEFA + 0.45%EtOH), 3) BASAL NEFA (720µM NEFA + 0.45%EtOH in the basal compartment), 4) APICAL NEFA (720µM NEFA + 0.45%EtOH in the apical compartment). FITC-albumin was used for monolayer permeability assessment, and related to Transepithelial Electric Resistance (TER). Fatty acid (FA), glucose, lactate and pyruvate concentrations were measured in spent medium. Intracellular lipid droplets (LD) and FA-uptake were studied using Bodipy 493/503 and immunolabelling of FA-transporters (FAT/CD36, FABP3 and caveolin1). BOEC-mRNA was retrieved for qRT-PCR. Results revealed that APICAL NEFA reduced relative TER-increase (46.85%) during treatment, and increased FITC-albumin flux (27.59%) compared to other treatments. In BASAL NEFA, FAs were transferred to the apical compartment as free FAs: mostly palmitic and oleic acid increased, respectively 56.0 % and 33.5% of initial FA-concentrations. APICAL NEFA allowed no FA-transfer, but induced LD-accumulation and upregulated FA-transporter expression (↑CD36, ↑FABP3, ↑CAV1-protein-expression). Gene expression in APICAL NEFA indicated increased anti-apoptotic (↑BCL2) and anti-oxidative (↑SOD1) capacity, upregulated lipid metabolism (↑CPT1, ↑ACSL1 and ↓ACACA), and FA-uptake (↑CAV1). All treatments had similar carbohydrate metabolism and oviduct function specific gene expression (=OVGP1, ESR1, FOXJ1). Overall, elevated NEFAs affected BOEC-metabolism and barrier function differently depending on NEFA-exposure side. Data substantiate the concept of the oviduct as a gatekeeper that may actively alter early embryonic developmental conditions.

  17. Root cooling strongly affects diel leaf growth dynamics, water and carbohydrate relations in Ricinus communis.

    PubMed

    Poiré, Richard; Schneider, Heike; Thorpe, Michael R; Kuhn, Arnd J; Schurr, Ulrich; Walter, Achim

    2010-03-01

    In laboratory and greenhouse experiments with potted plants, shoots and roots are exposed to temperature regimes throughout a 24 h (diel) cycle that can differ strongly from the regime under which these plants have evolved. In the field, roots are often exposed to lower temperatures than shoots. When the root-zone temperature in Ricinus communis was decreased below a threshold value, leaf growth occurred preferentially at night and was strongly inhibited during the day. Overall, leaf expansion, shoot biomass growth, root elongation and ramification decreased rapidly, carbon fluxes from shoot to root were diminished and carbohydrate contents of both root and shoot increased. Further, transpiration rate was not affected, yet hydrostatic tensions in shoot xylem increased. When root temperature was increased again, xylem tension reduced, leaf growth recovered rapidly, carbon fluxes from shoot to root increased, and carbohydrate pools were depleted. We hypothesize that the decreased uptake of water in cool roots diminishes the growth potential of the entire plant - especially diurnally, when the growing leaf loses water via transpiration. As a consequence, leaf growth and metabolite concentrations can vary enormously, depending on root-zone temperature and its heterogeneity inside pots.

  18. Carbohydrate metabolic pathway genes associated with quantitative trait loci (QTL) for obesity and type 2 diabetes: identification by data mining.

    PubMed

    Varma, Vijayalakshmi; Wise, Carolyn; Kaput, Jim

    2010-09-01

    Increasing consumption of refined carbohydrates is now being recognized as a primary contributor to the development of nutritionally related chronic diseases such as obesity and type 2 diabetes mellitus (T2DM). A data mining approach was used to evaluate the role of carbohydrate metabolic pathway genes in the development of obesity and T2DM. Data from public databases were used to map the position of the carbohydrate metabolic pathway genes to known quantitative trait loci (QTL) for obesity and T2DM and for examining the pathway genes for the presence of sequence and structural genetic variants such as single nucleotide polymorphisms (SNPs) and copy number variants (CNS), respectively. The results demonstrated that a majority of the genes of the carbohydrate metabolic pathways are associated with QTL for obesity and many for T2DM. In addition, some key genes of the pathways also encode non-synonymous SNPs that exhibit significant differences in population frequencies. This study emphasizes the significance of the metabolic pathways genes in the development of disease phenotypes, its differential occurrence across populations and between individuals, and a strategy for interpreting an individuals' risk for disease.

  19. Changes in the Expression of Carbohydrate Metabolism Genes during Three Phases of Bud Dormancy in Leafy Spurge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Underground adventitious buds of leafy spurge (Euphorbia esula) undergo three well-defined phases of dormancy, para-, endo-, and ecodormancy. In this study, relationships among genes involved in carbohydrate metabolism and bud dormancy were examined after paradormancy release (growth induction) by d...

  20. Bromochloromethane, a Methane Analogue, Affects the Microbiota and Metabolic Profiles of the Rat Gastrointestinal Tract

    PubMed Central

    Yang, Yu-Xiang; Mu, Chun-Long; Luo, Zhen

    2015-01-01

    Bromochloromethane (BCM), an inhibitor of methanogenesis, has been used in animal production. However, little is known about its impact on the intestinal microbiota and metabolic patterns. The present study aimed to investigate the effect of BCM on the colonic bacterial community and metabolism by establishing a Wistar rat model. Twenty male Wistar rats were randomly divided into two groups (control and treated with BCM) and raised for 6 weeks. Bacterial fermentation products in the cecum were determined, and colonic methanogens and sulfate-reducing bacteria (SRB) were quantified. The colonic microbiota was analyzed by pyrosequencing of the 16S rRNA genes, and metabolites were profiled by gas chromatography and mass spectrometry. The results showed that BCM did not affect body weight and feed intake, but it did significantly change the intestinal metabolic profiles. Cecal protein fermentation was enhanced by BCM, as methylamine, putrescine, phenylethylamine, tyramine, and skatole were significantly increased. Colonic fatty acid and carbohydrate concentrations were significantly decreased, indicating the perturbation of lipid and carbohydrate metabolism by BCM. BCM treatment decreased the abundance of methanogen populations, while SRB were increased in the colon. BCM did not affect the total colonic bacterial counts but significantly altered the bacterial community composition by decreasing the abundance of actinobacteria, acidobacteria, and proteobacteria. The results demonstrated that BCM treatment significantly altered the microbiotic and metabolite profiles in the intestines, which may provide further information on the use of BCM in animal production. PMID:26567308

  1. Carbohydrate Analysis

    NASA Astrophysics Data System (ADS)

    Bemiller, James N.

    Carbohydrates are important in foods as a major source of energy, to impart crucial textural properties, and as dietary fiber which influences physiological processes. Digestible carbohydrates, which are converted into monosaccharides, which are absorbed, provide metabolic energy. Worldwide, carbohydrates account for more than 70% of the caloric value of the human diet. It is recommended that all persons should limit calories from fat (the other significant source) to not more than 30% and that most of the carbohydrate calories should come from starch. Nondigestible polysaccharides (all those other than starch) comprise the major portion of dietary fiber (Sect. 10.5). Carbohydrates also contribute other attributes, including bulk, body, viscosity, stability to emulsions and foams, water-holding capacity, freeze-thaw stability, browning, flavors, aromas, and a range of desirable textures (from crispness to smooth, soft gels). They also provide satiety. Basic carbohydrate structures, chemistry, and terminology can be found in references (1, 2).

  2. Phylloxera (Daktulosphaira vitifoliae Fitch) alters the carbohydrate metabolism in root galls to allowing the compatible interaction with grapevine (Vitis ssp.) roots

    PubMed Central

    Griesser, Michaela; Lawo, Nora Caroline; Crespo-Martinez, Sara; Schoedl-Hummel, Katharina; Wieczorek, Krzysztof; Gorecka, Miroslawa; Liebner, Falk; Zweckmair, Thomas; Stralis Pavese, Nancy; Kreil, David; Forneck, Astrid

    2015-01-01

    Gall forming phylloxera may compete for nutrients with meristematic tissues and develop heterotrophic structures that act as carbon sinks. In this work, we studied the underlying starch metabolism, sink-source translocation of soluble sugars towards and within root galls. We demonstrated that nodosities store carbohydrates by starch accumulation and monitored the expression of genes involved in the starch metabolic. Thereby we proved that the nodosity is symplastically connected to the source tissues through its development and that the starch metabolism is significantly affected to synthesize and degrade starch within the gall. Genes required for starch biosynthesis and degradation are up-regulated. Among the carbohydrate transporters the expression of a glucose-6-phosphate translocater, one sucrose transporter and two SWEET proteins were increases, whereas hexose transporters, tonoplast monosaccharide transporter and Erd6-like sugar transporters were decreased. We found general evidence for plant response to osmotic stress in the nodosity as previously suggested for gall induction processes. We conclude that nodosities are heterogenous plant organs that accumulate starch to serve as temporary storage structure that is gradually withdrawn by phylloxera. Phylloxera transcriptionally reprograms gall tissues beyond primary metabolism and included downstream secondary processes, including response to osmotic stress. PMID:25804808

  3. Phylloxera (Daktulosphaira vitifoliae Fitch) alters the carbohydrate metabolism in root galls to allowing the compatible interaction with grapevine (Vitis ssp.) roots.

    PubMed

    Griesser, Michaela; Lawo, Nora Caroline; Crespo-Martinez, Sara; Schoedl-Hummel, Katharina; Wieczorek, Krzysztof; Gorecka, Miroslawa; Liebner, Falk; Zweckmair, Thomas; Stralis Pavese, Nancy; Kreil, David; Forneck, Astrid

    2015-05-01

    Gall forming phylloxera may compete for nutrients with meristematic tissues and develop heterotrophic structures that act as carbon sinks. In this work, we studied the underlying starch metabolism, sink-source translocation of soluble sugars towards and within root galls. We demonstrated that nodosities store carbohydrates by starch accumulation and monitored the expression of genes involved in the starch metabolic. Thereby we proved that the nodosity is symplastically connected to the source tissues through its development and that the starch metabolism is significantly affected to synthesize and degrade starch within the gall. Genes required for starch biosynthesis and degradation are up-regulated. Among the carbohydrate transporters the expression of a glucose-6-phosphate translocater, one sucrose transporter and two SWEET proteins were increases, whereas hexose transporters, tonoplast monosaccharide transporter and Erd6-like sugar transporters were decreased. We found general evidence for plant response to osmotic stress in the nodosity as previously suggested for gall induction processes. We conclude that nodosities are heterogenous plant organs that accumulate starch to serve as temporary storage structure that is gradually withdrawn by phylloxera. Phylloxera transcriptionally reprograms gall tissues beyond primary metabolism and included downstream secondary processes, including response to osmotic stress.

  4. Adipose tissue transcriptional response of lipid metabolism genes in growing Iberian pigs fed oleic acid v. carbohydrate enriched diets.

    PubMed

    Benítez, R; Núñez, Y; Fernández, A; Isabel, B; Rodríguez, C; Daza, A; López-Bote, C; Silió, L; Óvilo, C

    2016-06-01

    Diet influences animal body and tissue composition due to direct deposition and to the nutrients effects on metabolism. The influence of specific nutrients on the molecular regulation of lipogenesis is not well characterized and is known to be influenced by many factors including timing and physiological status. A trial was performed to study the effects of different dietary energy sources on lipogenic genes transcription in ham adipose tissue of Iberian pigs, at different growth periods and on feeding/fasting situations. A total of 27 Iberian male pigs of 28 kg BW were allocated to two separate groups and fed with different isocaloric feeding regimens: standard diet with carbohydrates as energy source (CH) or diet enriched with high oleic sunflower oil (HO). Ham subcutaneous adipose tissue was sampled by biopsy at growing (44 kg mean BW) and finishing (100 kg mean BW) periods. The first sampling was performed on fasted animals, while the last sampling was performed twice, with animals fasted overnight and 3 h after refeeding. Effects of diet, growth period and feeding/fasting status on gene expression were explored quantifying the expression of a panel of key genes implicated in lipogenesis and lipid metabolism processes. Quantitative PCR revealed several differentially expressed genes according to diet, with similar results at both timings: RXRG, LEP and FABP5 genes were upregulated in HO group while ME1, FASN, ACACA and ELOVL6 were upregulated in CH. The diet effect on ME1 gene expression was conditional on feeding/fasting status, with the higher ME1 gene expression in CH than HO groups, observed only in fasting samples. Results are compatible with a higher de novo endogenous synthesis of fatty acids (FA) in the carbohydrate-supplemented group and a higher FA transport in the oleic acid-supplemented group. Growth period significantly affected the expression of most of the studied genes, with all but PPARG showing higher expression in finishing pigs according to

  5. Iminosugar inhibitors of carbohydrate-active enzymes that underpin cereal grain germination and endosperm metabolism

    PubMed Central

    Andriotis, Vasilios M. E.; Rejzek, Martin; Rugen, Michael D.; Svensson, Birte; Smith, Alison M.; Field, Robert A.

    2016-01-01

    Starch is a major energy store in plants. It provides most of the calories in the human diet and, as a bulk commodity, it is used across broad industry sectors. Starch synthesis and degradation are not fully understood, owing to challenging biochemistry at the liquid/solid interface and relatively limited knowledge about the nature and control of starch degradation in plants. Increased societal and commercial demand for enhanced yield and quality in starch crops requires a better understanding of starch metabolism as a whole. Here we review recent advances in understanding the roles of carbohydrate-active enzymes in starch degradation in cereal grains through complementary chemical and molecular genetics. These approaches have allowed us to start dissecting aspects of starch degradation and the interplay with cell-wall polysaccharide hydrolysis during germination. With a view to improving and diversifying the properties and uses of cereal grains, it is possible that starch degradation may be amenable to manipulation through genetic or chemical intervention at the level of cell wall metabolism, rather than simply in the starch degradation pathway per se. PMID:26862201

  6. Iminosugar inhibitors of carbohydrate-active enzymes that underpin cereal grain germination and endosperm metabolism.

    PubMed

    Andriotis, Vasilios M E; Rejzek, Martin; Rugen, Michael D; Svensson, Birte; Smith, Alison M; Field, Robert A

    2016-02-01

    Starch is a major energy store in plants. It provides most of the calories in the human diet and, as a bulk commodity, it is used across broad industry sectors. Starch synthesis and degradation are not fully understood, owing to challenging biochemistry at the liquid/solid interface and relatively limited knowledge about the nature and control of starch degradation in plants. Increased societal and commercial demand for enhanced yield and quality in starch crops requires a better understanding of starch metabolism as a whole. Here we review recent advances in understanding the roles of carbohydrate-active enzymes in starch degradation in cereal grains through complementary chemical and molecular genetics. These approaches have allowed us to start dissecting aspects of starch degradation and the interplay with cell-wall polysaccharide hydrolysis during germination. With a view to improving and diversifying the properties and uses of cereal grains, it is possible that starch degradation may be amenable to manipulation through genetic or chemical intervention at the level of cell wall metabolism, rather than simply in the starch degradation pathway per se.

  7. The effects of space flight on some rat liver enzymes regulating carbohydrate and lipid metabolism

    NASA Technical Reports Server (NTRS)

    Abraham, S.; Lin, C. Y.; Klein, H. P.; Volkmann, C.

    1981-01-01

    The effects of space flight conditions on the activities of certain enzymes regulating carbohydrate and lipid metabolism in rat liver are investigated in an attempt to account for the losses in body weight observed during space flight despite preflight caloric consumption. Liver samples were analyzed for the activities of 32 cytosolic and microsomal enzymes as well as hepatic glycogen and individual fatty acid levels for ground control rats and rats flown on board the Cosmos 936 biosatellite under normal space flight conditions and in centrifuges which were sacrificed upon recovery or 25 days after recovery. Significant decreases in the activities of glycogen phosphorylase, alpha-glycerol phosphate acyl transferase, diglyceride acyl transferase, aconitase and 6-phosphogluconate dehydrogenase and an increase in palmitoyl CoA desaturase are found in the flight stationary relative to the flight contrifuged rats upon recovery, with all enzymes showing alterations returning to normal values 25 days postflight. The flight stationary group is also observed to be characterized by more than twice the amount of liver glycogen of the flight centrifuged group as well as a significant increase in the ratio of palmitic to palmitoleic acid. Results thus indicate metabolic changes which may be involved in the mechanism of weight loss during weightlessness, and demonstrate the equivalence of centrifugation during space flight to terrestrial gravity.

  8. How Phosphotransferase System-Related Protein Phosphorylation Regulates Carbohydrate Metabolism in Bacteria†

    PubMed Central

    Deutscher, Josef; Francke, Christof; Postma, Pieter W.

    2006-01-01

    The phosphoenolpyruvate(PEP):carbohydrate phosphotransferase system (PTS) is found only in bacteria, where it catalyzes the transport and phosphorylation of numerous monosaccharides, disaccharides, amino sugars, polyols, and other sugar derivatives. To carry out its catalytic function in sugar transport and phosphorylation, the PTS uses PEP as an energy source and phosphoryl donor. The phosphoryl group of PEP is usually transferred via four distinct proteins (domains) to the transported sugar bound to the respective membrane component(s) (EIIC and EIID) of the PTS. The organization of the PTS as a four-step phosphoryl transfer system, in which all P derivatives exhibit similar energy (phosphorylation occurs at histidyl or cysteyl residues), is surprising, as a single protein (or domain) coupling energy transfer and sugar phosphorylation would be sufficient for PTS function. A possible explanation for the complexity of the PTS was provided by the discovery that the PTS also carries out numerous regulatory functions. Depending on their phosphorylation state, the four proteins (domains) forming the PTS phosphorylation cascade (EI, HPr, EIIA, and EIIB) can phosphorylate or interact with numerous non-PTS proteins and thereby regulate their activity. In addition, in certain bacteria, one of the PTS components (HPr) is phosphorylated by ATP at a seryl residue, which increases the complexity of PTS-mediated regulation. In this review, we try to summarize the known protein phosphorylation-related regulatory functions of the PTS. As we shall see, the PTS regulation network not only controls carbohydrate uptake and metabolism but also interferes with the utilization of nitrogen and phosphorus and the virulence of certain pathogens. PMID:17158705

  9. Metabolic profiling reveals coordinated switches in primary carbohydrate metabolism in grape berry (Vitis vinifera L.), a non-climacteric fleshy fruit.

    PubMed

    Dai, Zhan Wu; Léon, Céline; Feil, Regina; Lunn, John E; Delrot, Serge; Gomès, Eric

    2013-03-01

    Changes in carbohydrate metabolism during grape berry development play a central role in shaping the final composition of the fruit. The present work aimed to identify metabolic switches during grape development and to provide insights into the timing of developmental regulation of carbohydrate metabolism. Metabolites from central carbon metabolism were measured using high-pressure anion-exchange chromatography coupled to tandem mass spectrometry and enzymatic assays during the development of grape berries from either field-grown vines or fruiting cuttings grown in the greenhouse. Principal component analysis readily discriminated the various stages of berry development, with similar trajectories for field-grown and greenhouse samples. This showed that each stage of fruit development had a characteristic metabolic profile and provided compelling evidence that the fruit-bearing cuttings are a useful model system to investigate regulation of central carbon metabolism in grape berry. The metabolites measured showed tight coordination within their respective pathways, clustering into sugars and sugar-phosphate metabolism, glycolysis, and the tricarboxylic acid cycle. In addition, there was a pronounced shift in metabolism around veraison, characterized by rapidly increasing sugar levels and decreasing organic acids. In contrast, glycolytic intermediates and sugar phosphates declined before veraison but remained fairly stable post-veraison. In summary, these detailed and comprehensive metabolite analyses revealed the timing of important switches in primary carbohydrate metabolism, which could be related to transcriptional and developmental changes within the berry to achieve an integrated understanding of grape berry development. The results are discussed in a meta-analysis comparing metabolic changes in climacteric versus non-climacteric fleshy fruits.

  10. Astrocyte-neuron crosstalk regulates the expression and subcellular localization of carbohydrate metabolism enzymes.

    PubMed

    Mamczur, Piotr; Borsuk, Borys; Paszko, Jadwiga; Sas, Zuzanna; Mozrzymas, Jerzy; Wiśniewski, Jacek R; Gizak, Agnieszka; Rakus, Dariusz

    2015-02-01

    Astrocytes releasing glucose- and/or glycogen-derived lactate and glutamine play a crucial role in shaping neuronal function and plasticity. Little is known, however, how metabolic functions of astrocytes, e.g., their ability to degrade glucosyl units, are affected by the presence of neurons. To address this issue we carried out experiments which demonstrated that co-culturing of rat hippocampal astrocytes with neurons significantly elevates the level of mRNA and protein for crucial enzymes of glycolysis (phosphofructokinase, aldolase, and pyruvate kinase), glycogen metabolism (glycogen synthase and glycogen phosphorylase), and glutamine synthetase in astrocytes. Simultaneously, the decrease of the capability of neurons to metabolize glucose and glutamine is observed. We provide evidence that neurons alter the expression of astrocytic enzymes by secretion of as yet unknown molecule(s) into the extracellular fluid. Moreover, our data demonstrate that almost all studied enzymes may localize in astrocytic nuclei and this localization is affected by the co-culturing with neurons which also reduces proliferative activity of astrocytes. Our results provide the first experimental evidence that the astrocyte-neuron crosstalk substantially affects the expression of basal metabolic enzymes in the both types of cells and influences their subcellular localization in astrocytes.

  11. Carbohydrate metabolism in two apple genotypes that differ in malate accumulation.

    PubMed

    Berüter, Josef

    2004-09-01

    In the apple variety 'Usterapfel', there are two known genotypes, which differ in malic acid content. One hundred days after full bloom, low-acid fruit (LA-fruit) contained 125 micromolg(-1) dry matter (DW) of malate, while the high-acid genotype (HA-fruit) reached levels up to 627 micromolg(-1) DW. There was no difference in the catalytic activity of enzymes involved in malate metabolism, such as PEPcarboxylase, malate dehydrogenase, and NADP malic enzyme. After [14C]glucose incorporation into the excised tissue of either genotype, the organic acid fraction was labeled to approximately the same extent. Furthermore, uptake of [14C]malate was significantly lower in excised tissue of LA-fruit. These findings suggest that low malate content in LA-fruit is the result of a restricted ability to accumulate malate in apple parenchyma cells. The different ability to accumulate malate had a pronounced effect on overall carbon partitioning. However, the rate of respiration and the rate of malate synthesis was similar in both genotypes. In HA-fruit, the glycolytic flux through pyruvate kinase was increased to compensate for the carbon that accumulated in the vacuole as malate. Since malate storage in the LA-fruit was restricted, it was more easily available for gluconeogenesis, and was correlated with a three-times higher activity of PEPcarboxykinase. LA-fruit showed higher concentrations of ATP, which stimulated Glc6P and fructose-6-phosphate formation. The elevated hexosephosphate content led to an enhanced partitioning of carbon into starch (+40%), hemicellulose (+104%), and sucrose (+40%) in more mature fruit. The activation of carbohydrate synthesis resulted in a significant drop in glucose-1-phosphate (Glc1P). To meet the increased demand for Glc1P, the activities of neutral and acid invertase, hexokinase, and phosphoglucomutase were higher in LA-fruit. Glucose was a more versatile substrate for this metabolic route than was fructose. It was also evident that glycolytic

  12. Differential Amino Acid, Carbohydrate and Lipid Metabolism Perpetuations Involved in a Subtype of Rheumatoid Arthritis with Chinese Medicine Cold Pattern

    PubMed Central

    Guo, Hongtao; Niu, Xuyan; Gu, Yan; Lu, Cheng; Xiao, Cheng; Yue, Kevin; Zhang, Ge; Pan, Xiaohua; Jiang, Miao; Tan, Yong; Kong, Hongwei; Liu, Zhenli; Xu, Guowang; Lu, Aiping

    2016-01-01

    Pattern classification is a key approach in Traditional Chinese Medicine (TCM), and it is used to classify the patients for intervention selection accordingly. TCM cold and heat patterns, two main patterns of rheumatoid arthritis (RA) had been explored with systems biology approaches. Different regulations of apoptosis were found to be involved in cold and heat classification in our previous works. For this study, the metabolic profiling of plasma was explored in RA patients with typical TCM cold or heat patterns by integrating liquid chromatography/mass spectrometry (LC/MS) and gas chromatography/mass spectrometry (GC/MS) platforms in conjunction with the Ingenuity Pathway Analysis (IPA) software. Three main processes of metabolism, including amino acid, carbohydrate and lipid were focused on for function analysis. The results showed that 29 and 19 differential metabolites were found in cold and heat patterns respectively, compared with healthy controls. The perturbation of amino acid metabolism (increased essential amino acids), carbohydrate metabolism (galactose metabolism) and lipid metabolism, were found to be involved in both cold and heat pattern RA. In particular, more metabolic perturbations in protein and collagen breakdown, decreased glycolytic activity and aerobic oxidation, and increased energy utilization associated with RA cold pattern patients. These findings may be useful for obtaining a better understanding of RA pathogenesis and for achieving a better efficacy in RA clinical practice. PMID:27775663

  13. [The role of adipokines in formation of lipid and carbohydrate metabolic disorders in patients with cardiovascular disease].

    PubMed

    Kravchun, P; Kadykova, O; Gabisoniia, T

    2012-12-01

    Cardio-vascular disease is an important public health problem in all developed countries.The challenge isto learn thepathogenic mechanisms of this disease.Attention of scientists of the world are drown to the role of hormones in the development of adipose tissue metabolic disorders. Adipose tissue is composed of adipocytes embedded in a loose connective tissue meshwork containing adipocyte precursors, fibroblasts, immune cells, and various other cell types. Adipose tissue was traditionally considered an energy storage depot with few interesting attributes. Due to the dramatic rise in obesity and its metabolic sequelae during the past decades, adipose tissue gained tremendous scientific interest. It is now regarded as an active endocrine organ that, in addition to regulating fat mass and nutrient homeostasis, releases a large number of bioactive mediators (adipokines) modulating hemostasis, blood pressure, lipid and glucose metabolism, inflammation, and atherosclerosis. The aim of our study was to examine the metabolic disorders in patients with cardiovascular disease. Based on identifying the nature of changes of insulin antagonists and of insulin sensitizers. We were investigated 68 patients with hypertension, which included 35 women and 33 men.Estimated distance of carbohydrate and lipid metabolism and adipose tissue hormone imbalance. Our results suggest that the mechanisms underlying the progression of diabetes and obesity in patients with hypertension against metabolic disorders that manifest dysfunction of carbohydrate and lipid metabolism are associated with insulinorezistense and hypervisfatinemia and hyperrezistinemia against hypoadiponektinemia occur in hypertensive patients by having diabetes mellitus type 2.

  14. Radio-metabolite analysis of carbon-11 biochemical partitioning to non-structural carbohydrates for integrated metabolism and transport studies.

    PubMed

    Babst, Benjamin A; Karve, Abhijit A; Judt, Tatjana

    2013-06-01

    Metabolism and phloem transport of carbohydrates are interactive processes, yet each is often studied in isolation from the other. Carbon-11 ((11)C) has been successfully used to study transport and allocation processes dynamically over time. There is a need for techniques to determine metabolic partitioning of newly fixed carbon that are compatible with existing non-invasive (11)C-based methodologies for the study of phloem transport. In this report, we present methods using (11)C-labeled CO2 to trace carbon partitioning to the major non-structural carbohydrates in leaves-sucrose, glucose, fructose and starch. High-performance thin-layer chromatography (HPTLC) was adapted to provide multisample throughput, raising the possibility of measuring different tissues of the same individual plant, or for screening multiple plants. An additional advantage of HPTLC was that phosphor plate imaging of radioactivity had a much higher sensitivity and broader range of sensitivity than radio-HPLC detection, allowing measurement of (11)C partitioning to starch, which was previously not possible. Because of the high specific activity of (11)C and high sensitivity of detection, our method may have additional applications in the study of rapid metabolic responses to environmental changes that occur on a time scale of minutes. The use of this method in tandem with other (11)C assays for transport dynamics and whole-plant partitioning makes a powerful combination of tools to study carbohydrate metabolism and whole-plant transport as integrated processes.

  15. Carbohydrate and dietary fiber

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carbohydrate provides 50 to 60% of the calories consumed by the average American. Although relatively little carbohydrate is needed in the diet, carbohydrate spares protein and fat being metabolized for calories. The principal dietary carbohydrates are sugars and starches. Sugars (simple carbohydrat...

  16. Attenuation of Helicteres isora L. bark extracts on streptozotocin-induced alterations in glycogen and carbohydrate metabolism in albino rats.

    PubMed

    Kumar, G; Sharmila Banu, G; Murugesan, A G

    2009-11-01

    The present study was undertaken to assess the effect of Helicteres isora L. on four important enzymes of carbohydrate metabolism (glucokinase [GK], hexokinase [HK] phosphofructokinase [PFK] and fructose-1, 6-bisphosphatase [FBP]) along with glycogen content of insulin-dependent (skeletal muscle and liver) and insulin-independent tissues (kidneys and brain) in streptozotocin (STZ; 60 mg/kg)-induced model of diabetes for 30 days. Administration of bark extracts (100, 200 mg/kg) for 30 days led to decrease in plasma glucose levels by approximately 9.60% and 22.04% and 19.18% and 33.93% on 15th and 30th day, respectively, of the experiment. Liver and two-kidney weight expressed as percentage of body weight significantly increased in diabetics (P < 0.05) versus normal controls. Renal glycogen content increased by 10 folds while hepatic and skeletal muscle glycogen content decreased by 75% and 68% in diabetic controls versus controls. H. isora did not affect glycogen content in any tissue. The decreased activities of PFK, GK, FBP and HK in diabetic controls were 40%, 50%, 50% and 60% and bark extract of H. isora partially corrected this alteration. The efficacy of the bark extract was comparable with Tolbutamide, a well-known hypoglycemic drug.

  17. Factors affecting metabolic syndrome by lifestyle

    PubMed Central

    Ki, Nam-Kyun; Lee, Hae-Kag; Cho, Jae-Hwan; Kim, Seon-Chil; Kim, Nak-Sang

    2016-01-01

    [Purpose] The aim of this study was to explore lifestyle factors in relation to metabolic syndrome so as to be able to utilize the results as baseline data for the furtherance of health-care and medical treatment. [Subjects and Methods] This study was conducted with patients who visited a health care center located in Seoul and had abdominal ultrasonography between 2 March 2013 and 28 February, 2014. Heights, weights, and blood pressures were measured by automatic devices. Three radiologists examined the patients using abdominal ultrasonography for gallstone diagnosis. The statuses of patients with regard to smoking, alcohol, coffee, and physical activities were explored for the lifestyle investigation. For investigating baseline demographics, we first used descriptive statistics. We then used the χ2 test to analyze lifestyles and gallstone prevalence with regard to the presence of metabolic syndrome. Lastly, logistic regression analysis was conducted to discover the risk factors of metabolic syndrome. [Results] For men, body mass index, maximum gallstone size, and waist circumference were revealed as risk factors for metabolic syndrome, in descending order of the degree of risk. For females, gallstone presence was the most significant risk factor, followed by waist circumference. [Conclusion] Metabolic disease mainly presents itself along with obesity, and we should become more focused on preventing and treating this disease. A large-scale prospective study is needed in the future, as the cause of nonalcoholic steatohepatitis remained unclear in this study. PMID:26957725

  18. The effects of space flight on some rat liver enzymes regulating carbohydrate and lipid metabolism

    NASA Astrophysics Data System (ADS)

    Abraham, S.; Lin, C. Y.; Klein, H. P.; Volkmann, C.

    We have examined, in the livers of rats carried aboard the Cosmos 936 biosatellite, the activities of about 30 enzymes concerned with carbohydrate and lipid metabolism. In addition to the enzyme studies, the levels of glycogen and of the individual fatty acids in hepatic lipids were determined. Livers from flight and ground control rats at recovery (R0) and 25 days after recovery (R25) were used for these analyses. For all parameters measured, the most meaningful comparisons are those made between flight stationary (FS) and flight centrifuged (FC) animals at R0. When these two groups of flight rats were compared at R0, statistically significant decreases in the activity levels of glycogen phosphorylase, α-glycerol phosphate acyl transferase, diglyceride acyl transferase, aconitase and 6-phosphogluconate dehydrogenase and an increase in the palmitoyl CoA desaturase were noted in the weightless group (FS). The significance of these findings was strengthened by the fact that all enzyme activities showing alterations at R0 returned to normal 25 days postflight. When liver glycogen and total fatty acids of the two sets of flight animals were determined, significant differences that could be attributed to reduced gravity were observed. The weightless group (FS) at R0 contained, on the average, more than twice the amount of glycogen than did the centrifuged controls (FC) and a remarkable shift in the ratio of palmitate to palmitoleate was noted. These metabolic alterations, both in enzyme levels and in hepatic constituents, appear to be characteristic of the weightless condition. Our data seem to justify the conclusion that centrifugation during flight is equivalent to terrestrial gravity.

  19. Effect of hyperthyroidism and hypothyroidism on lipid and carbohydrate metabolism of the perfused rat liver.

    PubMed Central

    Laker, M E; Mayes, P A

    1981-01-01

    1. Liver from hyper- and hypo-thyroid male fed rats were perfused with whole blood and their metabolism was compared with euthyroid controls. 2. Hyperthyroid livers produced more bile than controls and hypothyroid livers produced less. 3. Glucose output by all livers was similar; glycogen declined only during perfusion of hyperthyroid livers. Lactate uptake increased in hyperthyroid but decreased in hypothyroid livers. These results may be explained by changes in oxidation of carbohydrate rather than in gluconeogenesis. 4. Secretion of triacylglycerol was decreased in hyperthyroid and not changed significantly in hypothyroid livers. 5. Fractional extraction of infused [1-14C]oleate was unaltered. Hyperthyroid livers oxidized more oleate to CO2 and ketone bodies, esterified less and incorporated less into lipoproteins of d less than 1.006. Hypothyroid livers oxidized and esterified oleate to the same extent as controls; their decreased O2 consumption was due to diminished oxidation of other (non-lipid) substrates; 14C-labelled ketone-body formation was increased, but at the expense of 14CO2 production. 6. Lipogenesis (measured with 3H2O) was unaltered in hyperthyroid but was decreased in hypothyroid livers. Incorporation of 3H and 14C into triacylglycerol relative to phospholipid decreased in hyperthyroid and increased in hypothyroid livers. Cholesterol synthesis was similar in all perfusions. 7. During oleate infusion, the cytosolic redox state, as indicated by the perfusate [lactate]/[pyruvate] ratio, was decreased in hyperthyroid and increased in hypothyroid livers. No change in [3-hydroxybutyrate]/[acetoacetate] was detected. 8. The importance of relating the concentration of plasma non-esterified fatty acids to the interpretation of metabolic data obtained under differing thyroid status is emphasized. PMID:7306071

  20. The metabolism of carbohydrates and lipid peroxidation in lead-exposed workers.

    PubMed

    Kasperczyk, Aleksandra; Dobrakowski, Michal; Ostałowska, Alina; Zalejska-Fiolka, Jolanta; Birkner, Ewa

    2015-12-01

    The present study was undertaken to estimate the effect of occupational exposure to lead on the blood concentration of glucose and several enzymes involved in glycolysis, the citric acid cycle, and the pentose phosphate pathway. To estimate the degree of lipid peroxidation, the concentrations of conjugated dienes were determined. The examined group included 145 healthy male employees of lead-zinc works. Taking into account the mean blood lead levels, the examined group was divided into two subgroups. The control group was composed of 36 healthy male administrative workers. The markers of lead exposure were significantly elevated in both subgroups when compared with the controls. There were no significant changes in fasting glucose concentration and fructose-1,6-bisphosphate aldolase activity in the study population. The concentration of conjugated dienes was significantly higher in both subgroups, whereas the activity of malate dehydrogenase was significantly higher only in the group with higher exposure. The activities of lactate dehydrogenase and sorbitol dehydrogenase were significantly decreased in the examined subgroups. The activity of glucose-6-phosphate dehydrogenase decreased significantly in the group with higher exposure and could be the cause of the elevated concentrations of conjugated dienes. It is possible to conclude that lead interferes with carbohydrate metabolism, but compensatory mechanisms seem to be efficient, as glucose homeostasis in lead-exposed workers was not disturbed.

  1. Efficacy of dietary supplementation with botanicals on carbohydrate metabolism in humans.

    PubMed

    Cefalu, William T; Ye, Jianping; Wang, Zhong Q

    2008-06-01

    Botanical products are widely used in nutritional supplementation for promotion of health or prevention of diseases. With the high prevalence of obesity and type 2 diabetes, abnormalities in carbohydrate metabolism are common in the general population and obtaining glycemic control is important in reducing the complications of diabetes. If shown to be effective, botanical products have a unique position in potentially aiding the general public in regard to obesity and diabetes. They can be obtained "over-the-counter" and may have less side effects compared to many synthetic drugs. Although most of the popular botanicals have a long history in folk medicine, there is paucity of data regarding their efficacy and safety, particularly as it relates to human studies. In this review, we discuss the data that was available in the literature for nine botanicals that are frequently promoted to help manage blood glucose. They are Bitter Melon (Momordica charantia), Fenugreek (trigonella foenum graecum), Gymnema Sylvestre, Ivy Gourd (Coccinia indica), Nopal or Prickly Pear Cactus (Opuntia streptacantha), Ginseng, Aloe Vera, Russian Tarragon (Artemisia dracunculus), and Garlic (Allium sativum). The discussion is emphasized on the clinical aspect of these botanicals. Due to the lack of sufficient evidence from clinical studies for any of the botanicals reviewed, it is premature to actively recommend use of any particular herb to treat either glucose or other risk factors. Thus, well defined randomized clinical trials are warranted in this area.

  2. Carbohydrate metabolism changes in Prunus persica gummosis infected with Lasiodiplodia theobromae.

    PubMed

    Li, Z; Gao, L; Wang, Y T; Zhu, W; Ye, J L; Li, G H

    2014-05-01

    Peach gummosis represents a significant global disease of stone fruit trees and a major disease in the south peach production area of the Yangtze River of China. In this study, the carbohydrate composition of peach shoots during infection by Lasiodiplodia theobromae was examined. The expression of genes related to metabolic enzymes was also investigated. Control wounded and noninoculated tissue, lesion tissue, and wounded and inoculated surrounding lesion tissue of peach shoots were analyzed. Soluble sugars, glucose, mannose, arabinose, and xylose significantly increased in inoculated tissues of peach shoots compared with control tissues at different times after inoculation. Accumulation of polysaccharides was also observed by section observation and periodic acid Schiff's reagent staining during infection. Analysis using quantitative reverse-transcription polymerase chain reaction revealed that the abundance of key transcripts on the synthesis pathway of uridine diphosphate (UDP)-D-glucuronate, UDP-D-galactose, and UDP-D-arabinose increased but the synthesis of L-galactose and guanosine diphosphate-L-galactose were inhibited. After inoculation, the transcript levels of sugar transport-related genes (namely, SUT, SOT, GMT, and UGT) was induced. These changes in sugar content and gene expression were directly associated with peach gum polysaccharide formation and may be responsible for the symptoms of peach gummosis.

  3. Long-term effects of nifedipine on carbohydrate and lipid metabolism in hypertensive hemodialyzed patients.

    PubMed

    Riegel, W; Hörl, W H; Heidland, A

    1986-10-31

    To evaluate long-term effects of nifedipine on carbohydrate and lipid metabolism, 15 hypertensive patients undergoing regular hemodialysis treatment were investigated before nifedipine therapy, after 3 and 9 weeks, and 2 weeks after stopping nifedipine therapy. Three weeks following the administration of nifedipine, both glucose and insulin concentrations decreased significantly from 102.1 +/- 2.6 to 94.9 +/- 2.2 mg/dl and from 19.9 +/- 2.9 to 13.9 +/- 1.7 microU/ml and also remained significantly lower after 9 weeks of nifedipine therapy. This effect was paralleled by a fall of noradrenaline and dopamine. Glucagon levels remained constant. Glucose tolerance tests performed during nifedipine medication and 2 weeks after stopping of nifedipine therapy did not differ significantly. An increase of pyruvate, citric acid cycle intermediates, and ketone bodies--but not of lactate--was registered during nifedipine medication. The observed effects were not completely abolished after the 2-week placebo phase. Our data indicate that nifedipine lowers serum glucose values despite decreased insulin and constant glucagon levels in hypertensive hemodialyzed patients. Considering additionally the behavior of catecholamines and organic acids, the effects could be explained by the improvement of peripheral glucose utilization.

  4. Territorial aggression, body weight, carbohydrate metabolism and testosterone levels of wild rats maintained in laboratory colonies.

    PubMed

    Lucion, A B; De-Almeida, R M; Da-Silva, R S

    1996-12-01

    Aggressive territorial behavior was studied in 15 colonies of wild rats (Rattus norvegicus), each consisting of 2 males and 1 female. One of the males attacked an intruder rat more frequently and had a higher body weight than the less aggressive one. In another experiment, male and female rats were raised in colonies from weaning to adulthood. Animals were weighed every 7 days until 90 days of age when plasma testosterone was measured in males, and plasma glucose, hepatic and muscle glycogen were measured in both males and females. THe heavier (and thus possibly dominant) males in the colonies of 3 males and 1 female also had a higher body weight than males raised with females, but without any male partner. In this long-term social relationship there were no significant differences in carbohydrate metabolism among the animals. The differential growth rate among males was established around the period of sexual maturity. Moreover, when adult, heavier males had higher plasma testosterone levels compared to the other members of the colony and also to males that had no other competitive male partner. This higher androgenic hormone level may be one of the causal factors involved in the weight increase of the dominant male in the colony.

  5. Expression profiles of genes related to carbohydrate metabolism provide new insights into carbohydrate accumulation in seeds and seedlings of Ricinus communis in response to temperature.

    PubMed

    Ribeiro, Paulo R; Ligterink, Wilco; Hilhorst, Henk W M

    2015-10-01

    Ricinus communis possesses a specific metabolic signature to adjust growth and developmental processes in response to temperature: carbohydrates are accumulated at low temperatures, whereas amino acids are accumulated at elevated temperatures. Our objective was to assess tissue-specific changes in transcript levels of genes related with carbohydrate biosynthesis and catabolism in response to temperature. For that, we measured transcript levels of genes encoding enzymes involved in starch biosynthesis, starch catabolism, and gluconeogenesis in R. communis leaves, roots, and seeds grown at 20 °C and 35 °C. Transcript levels of genes involved in starch catabolism were higher in leaves grown at 20 °C than at 35 °C, but up-regulation of genes involved in starch biosynthesis seems to compensate for this and, therefore, are the likely explanation for higher levels of starch in leaves grown at 20 °C. Higher levels of soluble carbohydrates in leaves grown at 20 °C may be caused by a coordinated increase in transcript level of genes associated with starch catabolism and gluconeogenesis pathways. In roots, transcript levels of genes associated with starch catabolism and gluconeogenesis seem to be enhanced at elevated temperatures. Higher levels of starch in seeds germinated at low temperatures is associated with higher transcript levels of genes involved in starch biosynthesis. Similarly, higher transcript levels of RcPEPCK and RcFBPase are most likely causal for fructose and glucose accumulation in seeds germinated at 20 °C. This study provides important insights in the understanding of the plasticity of R. communis in response to temperature that may apply to other species as well.

  6. Investigation of carbohydrate and protein metabolism in the digestive organs of the rabbit under the combined influence of vibration, acceleration and irradiation

    NASA Technical Reports Server (NTRS)

    Yuy, R. I.

    1975-01-01

    During spaceflight, the organism is subjected to the influence of various extremal factors such as acceleration, vibration, irradiation, etc. The study of the influence of these factors on metabolism, especially carbohydrate and protein metabolism, in young rabbits is of great significance in simulation experiments. Dynamic factors and irradiation, depending on dose and duration, lead to reduced RNA and protein metabolism.

  7. [Insulin resistance and carbohydrate metabolism indexes in women of reproductive age depending on the type of their breast-feeding in infancy].

    PubMed

    Starodubova, A V

    2011-01-01

    Determine what in women in early age exceptionally on artificial nutrition risk beginning insulin resistance and breach carbohydrate metabolism more high than in women receive in pectoral age naturally nutrition. This relation especially distinctly reveals in women with obesity.

  8. Effects of Carbohydrate and Dietary Fiber Intake, Glycemic Index and Glycemic Load on HDL Metabolism in Asian Populations.

    PubMed

    Yanai, Hidekatsu; Katsuyama, Hisayuki; Hamasaki, Hidetaka; Abe, Shinichi; Tada, Norio; Sako, Akahito

    2014-10-01

    High-density lipoprotein (HDL) is a lipoprotein which has anti-atherogenic property by reverse cholesterol transport from the peripheral tissues to liver. Low HDL-cholesterol (HDL-C) levels are associated with the development of coronary artery diseases (CADs). Various epidemiological studies have suggested that the development of CAD increase in individuals with less than 40 mg/dL of HDL-C. In spite of accumulation of evidences which suggest a significant association between low HDL-C and cardiovascular diseases, effects of dietary factors on HDL metabolism remained largely unknown. There may be interracial differences in effects of dietary factors on HDL metabolism. Here we reviewed published articles about effects of carbohydrate and dietary fiber intake, glycemic index (GI) and glycemic load (GL), on HDL-C metabolism, regarding meta-analyses and clinical studies performed in Asian population as important articles. Low carbohydrate intake, GI and GL may be beneficially associated with HDL metabolism. Dietary fiber intake may be favorably associated with HDL metabolism in Asian populations.

  9. Effects of Taurine Administration on Carbohydrate Metabolism in Skeletal Muscle during the Post-Exercise Phase.

    PubMed

    Takahashi, Yumiko; Tamura, Yuki; Matsunaga, Yutaka; Kitaoka, Yu; Terada, Shin; Hatta, Hideo

    2016-01-01

    We previously reported that taurine (2-aminoethanesulfonic acid; dose: 0.5 mg/g body weight) administration after treadmill running at 25 m/min for 90 min increased the glycogen concentration in the skeletal muscle of ICR mice at 120 min after the exercise (Takahashi et al. 2014). In the current study, we further investigated the effects of taurine administration on glycogen repletion and carbohydrate metabolism in the tibialis anterior muscle after endurance exercise. The metabolomic profiles of the tibialis anterior muscle at 120 min after the exercise were analyzed by a capillary electrophoresis-time-of-flight mass spectrometry (n=6). Fructose-1,6-bisphosphate (F1,6P), a glycogenolytic/glycolytic intermediate produced by phosphofructokinase, was significantly lower in the taurine-treated group than that in the control group (p<0.01). Dihydroxyacetonephosphate (DHAP), a downstream product of F1,6P was lower (p=0.05) and glycerol 3-phosphate, a downstream product of F1,6P and DHAP, tended to be lower (p=0.09) in the taurine-treated group than in the controls. At that time, phosphorylated Ser(293) on the E1α subunit of pyruvate dehydrogenase (PDH) tended to be higher in the taurine-treated mice than in the controls (p=0.09, n=5). There was a positive correlation between phosphorylation of the PDH E1α subunit at Ser(293) and glycogen concentration (r=0.73, p<0.05). Our results showed that the enhanced glycogen repletion in skeletal muscle by taurine treatment during the post-exercise phase was accompanied by the lower levels of glycogenolytic/glycolytic intermediates.

  10. Ferulic Acid Alleviates Changes in a Rat Model of Metabolic Syndrome Induced by High-Carbohydrate, High-Fat Diet.

    PubMed

    Senaphan, Ketmanee; Kukongviriyapan, Upa; Sangartit, Weerapon; Pakdeechote, Poungrat; Pannangpetch, Patchareewan; Prachaney, Parichat; Greenwald, Stephen E; Kukongviriyapan, Veerapol

    2015-08-04

    Metabolic syndrome is a cluster of metabolic abnormalities characterized by obesity, insulin resistance, hypertension and dyslipidemia. Ferulic acid (FA) is the major phenolic compound found in rice oil and various fruits and vegetables. In this study, we examined the beneficial effects of FA in minimizing insulin resistance, vascular dysfunction and remodeling in a rat model of high-carbohydrate, high-fat diet-induced metabolic changes, which is regarded as an analogue of metabolic syndrome (MS) in man. Male Sprague-Dawley rats were fed a high carbohydrate, high fat (HCHF) diet and 15% fructose in drinking water for 16 weeks, where control rats were fed with standard chow diet and tap water. FA (30 or 60 mg/kg) was orally administered to the HCHF and control rats during the last six weeks of the study. We observed that FA significantly improved insulin sensitivity and lipid profiles, and reduced elevated blood pressure, compared to untreated controls (p < 0.05). Moreover, FA also improved vascular function and prevented vascular remodeling of mesenteric arteries. The effects of FA in HCHF-induced MS may be realized through suppression of oxidative stress by down-regulation of p47phox, increased nitric oxide (NO) bioavailability with up-regulation of endothelial nitric oxide synthase (eNOS) and suppression of tumor necrosis factor-α (TNF-α). Our results suggest that supplementation of FA may have health benefits by minimizing the cardiovascular complications of MS and alleviating its symptoms.

  11. Metabolism of organic acids, nitrogen and amino acids in chlorotic leaves of 'Honeycrisp' apple (Malus domestica Borkh) with excessive accumulation of carbohydrates.

    PubMed

    Wang, Huicong; Ma, Fangfang; Cheng, Lailiang

    2010-07-01

    Metabolite profiles and activities of key enzymes in the metabolism of organic acids, nitrogen and amino acids were compared between chlorotic leaves and normal leaves of 'Honeycrisp' apple to understand how accumulation of non-structural carbohydrates affects the metabolism of organic acids, nitrogen and amino acids. Excessive accumulation of non-structural carbohydrates and much lower CO(2) assimilation were found in chlorotic leaves than in normal leaves, confirming feedback inhibition of photosynthesis in chlorotic leaves. Dark respiration and activities of several key enzymes in glycolysis and tricarboxylic acid (TCA) cycle, ATP-phosphofructokinase, pyruvate kinase, citrate synthase, aconitase and isocitrate dehydrogenase were significantly higher in chlorotic leaves than in normal leaves. However, concentrations of most organic acids including phosphoenolpyruvate (PEP), pyruvate, oxaloacetate, 2-oxoglutarate, malate and fumarate, and activities of key enzymes involved in the anapleurotic pathway including PEP carboxylase, NAD-malate dehydrogenase and NAD-malic enzyme were significantly lower in chlorotic leaves than in normal leaves. Concentrations of soluble proteins and most free amino acids were significantly lower in chlorotic leaves than in normal leaves. Activities of key enzymes in nitrogen assimilation and amino acid synthesis, including nitrate reductase, glutamine synthetase, ferredoxin and NADH-dependent glutamate synthase, and glutamate pyruvate transaminase were significantly lower in chlorotic leaves than in normal leaves. It was concluded that, in response to excessive accumulation of non-structural carbohydrates, glycolysis and TCA cycle were up-regulated to "consume" the excess carbon available, whereas the anapleurotic pathway, nitrogen assimilation and amino acid synthesis were down-regulated to reduce the overall rate of amino acid and protein synthesis.

  12. Carbohydrate affects natural killer cell redistribution but not activity after running.

    PubMed

    Nieman, D C; Henson, D A; Garner, E B; Butterworth, D E; Warren, B J; Utter, A; Davis, J M; Fagoaga, O R; Nehlsen-Cannarella, S L

    1997-10-01

    This randomized, double-blind, placebo-controlled study was designed to determine the influence of carbohydrate supplementation on the natural killer cell response to 2.5 h of high-intensity running (76.7 +/- 0.4% VO2max). Thirty experienced marathon runners (VO2max 53.4 +/- 1.0 mL x kg[-1] x min[-1], age 41.5 +/- 1.4 yr) were randomized into carbohydrate supplement (N = 17) and placebo (N = 13) groups. Subjects rested for 10-15 min before a blood sample at 0715, and then ingested 0.75 L of carbohydrate beverage (Gatorade) or placebo. At 0730, subjects began running at 75-80% VO2max for 2.5 h and drank 0.25 L of carbohydrate or placebo fluid every 15 min. Immediately after the 2.5 h run (1000), another blood sample was taken, followed by 1.5 h, 3 h, and 6-h recovery samples. Carbohydrate supplementation versus placebo had a significant effect on the pattern of change in glucose, cortisol, and the blood concentration of natural killer cells ([F (4,25) = 3.79, P = 0.015], but not natural killer cell activity following 2.5 h of intensive running.

  13. Algal carbohydrates affect polyketide synthesis of the lichen-forming fungus Cladonia rangiferina.

    PubMed

    Elshobary, Mostafa E; Osman, Mohamed E; Abo-Shady, Atef M; Komatsu, Emy; Perreault, Hélène; Sorensen, John; Piercey-Normore, Michele D

    2016-01-01

    Lichen secondary metabolites (polyketides) are produced by the fungal partner, but the role of algal carbohydrates in polyketide biosynthesis is not clear. This study examined whether the type and concentration of algal carbohydrate explained differences in polyketide production and gene transcription by a lichen fungus (Cladonia rangiferina). The carbohydrates identified from a free-living cyanobacterium (Spirulina platensis; glucose), a lichen-forming alga (Diplosphaera chodatii; sorbitol) and the lichen alga that associates with C. rangiferina (Asterochloris sp.; ribitol) were used in each of 1%, 5% and 10% concentrations to enrich malt yeast extract media for culturing the mycobiont. Polyketides were determined by high performance liquid chromatography (HPLC), and polyketide synthase (PKS) gene transcription was measured by quantitative PCR of the ketosynthase domain of four PKS genes. The lower concentrations of carbohydrates induced the PKS gene expression where ribitol up-regulated CrPKS1 and CrPKS16 gene transcription and sorbitol up-regulated CrPKS3 and CrPKS7 gene transcription. The HPLC results revealed that lower concentrations of carbon sources increased polyketide production for three carbohydrates. One polyketide from the natural lichen thallus (fumarprotocetraric acid) also was produced by the fungal culture in ribitol supplemented media only. This study provides a better understanding of the role of the type and concentration of the carbon source in fungal polyketide biosynthesis in the lichen Cladonia rangiferina.

  14. Beneficiary effect of Tinospora cordifolia against high-fructose diet induced abnormalities in carbohydrate and lipid metabolism in Wistar rats.

    PubMed

    Reddy, S Sreenivasa; Ramatholisamma, P; Ramesh, B; Baskar, R; Saralakumari, D

    2009-10-01

    High intake of dietary fructose has been shown to exert a number of adverse metabolic eff ects in humans and experimental animals. The present study was designed to investigate the eff ect of the aqueous extract of Tinospora cordifolia stem (TCAE) on the adverse eff ects of fructose loading toward carbohydrate and lipid metabolism in rats. Adult male Wistar rats of body weight around 200 g were divided into four groups, two of which were fed with starch diet and the other two with high fructose (66 %) diet. Plant extract of TC (400 mg/kg/day) was administered orally to each group of the starch fed rats and the highfructose fed rats. At the end of 60 days of experimental period, biochemical parameters related to carbohydrate and lipid metabolism were assayed. Hyperglycemia, hyperinsulinemia, hypertriglyceridemia, insulin resistance, and elevated levels of hepatic total lipids, cholesterol, triglycerides, and free fatty acids (p < 0.05) observed in fructose-fed rats were completely prevented with TCAE treatment. Alterations in the activities of enzymes of glucose metabolism (hexokinase, phosphofructokinase, pyruvate kinase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, and glucose-6-phosphate dehydrogenase) and lipid metabolism (fatty acid synthetase, lipoprotein lipase, and malic enzyme) as observed in the high fructose-fed rats were prevented with TCAE administration. In conclusion, our fi ndings indicate improvement of glucose and lipid metabolism in high-fructose fed rats by treatment with Tinospora cordifolia, and suggest that the plant can be used as an adjuvant for the prevention and/or management of insulin resistance and disorders related to it.

  15. The influence of carbohydrate quality on cardiovascular disease, the metabolic syndrome, type 2 diabetes, and obesity - an overview.

    PubMed

    Slyper, Arnold H

    2013-01-01

    There is compelling evidence that carbohydrate quality has important influences on cardiovascular disease, the metabolic syndrome, type 2 diabetes, and obesity. Cohort and interventional studies indicate that dietary fiber is an important determinant of satiation, satiety, and weight gain, and also protects against cardiovascular disease. Cohort studies have shown that vegetables and fruits protect against coronary heart disease, whereas whole grains provide protection against cardiovascular disease, type 2 diabetes, and weight gain. Dietary glycemia within the range eaten by most of the population seems not to have a significant influence on body weight, although it may influence waist circumference. There is strong evidence from interventional trials that dietary glycemia does influence insulin resistance and diabetes control. Moreover, replacing saturated fat with high-glycemic carbohydrate may increase cardiovascular risk. Soft drink consumption is a proven cause of weight gain, which may relate to the lack of satiation provided by these drinks. In large amounts, dietary fructose leads to greater adverse metabolic changes than equivalent amounts of glucose, although the extent to which fructose per se is contributing to many of the metabolic changes found in the obese, as distinct from the calories it provides, is still a matter of debate.

  16. Cross-sectional relationship between dietary carbohydrate, glycaemic index, glycaemic load and risk of the metabolic syndrome in a Korean population.

    PubMed

    Kim, Kirang; Yun, Sung Ha; Choi, Bo Youl; Kim, Mi Kyung

    2008-09-01

    Little is known about the effect of dietary carbohydrate, glycaemic index (GI) and glycaemic load (GL) on the risk of the metabolic syndrome, especially in populations with white rice as the staple food. The study examined the cross-sectional relationship between carbohydrate, GI, GL and risk of the metabolic syndrome. There were a total of 910 middle-aged Korean adults. Dietary carbohydrate, GI and GL were determined by an interview-administered FFQ. The metabolic syndrome was defined using the modified criteria published in the Third Report of the National Cholesterol Education Program Adult Treatment Panel III. The risk of developing the metabolic syndrome was positively related to dietary carbohydrate (P for trend = 0.03), GI (P for trend = 0.03) and GL intakes (P for trend = 0.02) in women after adjusting for potential confounding variables. Among the components of developing the metabolic syndrome, the risk of high TAG and low HDL-cholesterol were positively related to high GI and GL intakes in women. The risk of developing the metabolic syndrome was considerably higher in the highest quintiles of carbohydrate (OR 6.44; 95 % CI 2.16, 19.2), GI (OR 10.4; 95 % CI 3.24, 33.3) and GL intakes (OR 6.68; 95 % CI 2.30, 19.4) than in the lowest quintiles among women with a BMI >/= 25 kg/m2. However, there was no difference in risk across quintiles of carbohydrate, GI and GL among women with a BMI < 25 kg/m2. In conclusion, both the quantity and quality of carbohydrate intake has a positive relationship with the risk of the metabolic syndrome in women but this relationship was dependent on the BMI level.

  17. Association of neural tube defects in children of mothers with MTHFR 677TT genotype and abnormal carbohydrate metabolism risk: a case-control study.

    PubMed

    Cadenas-Benitez, N M; Yanes-Sosa, F; Gonzalez-Meneses, A; Cerrillos, L; Acosta, D; Praena-Fernandez, J M; Neth, O; Gomez de Terreros, I; Ybot-González, P

    2014-03-26

    Abnormalities in maternal folate and carbohydrate metabolism have both been shown to induce neural tube defects (NTD) in humans and animal models. However, the relationship between these two factors in the development of NTDs remains unclear. Data from mothers of children with spina bifida seen at the Unidad de Espina Bífida del Hospital Infantil Virgen del Rocío (case group) were compared to mothers of healthy children with no NTD (control group) who were randomly selected from patients seen at the outpatient ward in the same hospital. There were 25 individuals in the case group and 41 in the control group. Analysis of genotypes for the methylenetetrahydrofolate reductase (MTHFR) 677CT polymorphism in women with or without risk factors for abnormal carbohydrate metabolism revealed that mothers who were homozygous for the MTHFR 677TT polymorphism and at risk of abnormal carbohydrate metabolism were more likely to have offspring with spina bifida and high levels of homocysteine, compared to the control group. The increased incidence of NTDs in mothers homozygous for the MTHFR 677TT polymorphism and at risk of abnormal carbohydrate metabolism stresses the need for careful metabolic screening in pregnant women, and, if necessary, determination of the MTHFR 677CT genotype in those mothers at risk of developing abnormal carbohydrate metabolism.

  18. Spermine Alleviates Drought Stress in White Clover with Different Resistance by Influencing Carbohydrate Metabolism and Dehydrins Synthesis

    PubMed Central

    Li, Zhou; Jing, Wen; Peng, Yan; Zhang, Xin Quan; Ma, Xiao; Huang, Lin Kai; Yan, Yan-hong

    2015-01-01

    The objective of this research was to analyse whether ameliorating drought stress through exogenously applied spermine (Spm) was related to carbohydrate metabolism, dehydrins accumulation and the transcription of genes encoding dehydrins in two white clovers (drought-susceptible cv. ‘Ladino’ and drought-resistant cv. ‘Haifa’) under controlled drying conditions for 10 days. The results show that the application of Spm effectively alleviates negative effects caused by drought stress in both cultivars. Exogenous Spm led to accumulation of more water-soluble carbohydrates (WSC), sucrose, fructose and sorbitol in both cultivars under drought stress, and also significantly elevated glucose content in leaves of drought-resistant cv. ‘Haifa’, but had no effect on drought-susceptible cv. ‘Ladino’. Accordingly, the key enzyme activities of sucrose and sorbitol metabolism changed along with the application of Spm under drought stress. Spm induced a significant increase in sucrose phosphate synthase (SPS) or sorbitol dehydrogenase (SDH) activity, but decrease in sucrose synthetase (SS) activity when two cultivars were subjected to drought. In addition, the improved accumulation of dehydrins induced by exogenous Spm coincided with three genes expression which was responsible for dehydrins synthesis. But Spm-induced transcript level of dehydrin genes increased earlier in cv. ‘Ladino’ than that in cv. ‘Haifa’. Thus, these results suggest that ameliorating drought stress through exogenously applied Spm may be associated with increased carbohydrate accumulation and dehydrins synthesis. There are differences between drought-susceptible and -resistant white clover cultivars related to Spm regulation of WSC metabolism and dehydrins expression. PMID:25835290

  19. [Development of lipids and carbohydrates metabolism disorders caused by drinkable water with high content of chlorine organic compounds].

    PubMed

    Luzhetsky, K P; Ustinova, O Yu; Shur, P Z; Kiryanov, D A; Dolgikh, O V; Chigvintsev, v M; Perevalov, A Ya

    2015-01-01

    Evaluation of effects caused by environmental peroral exposure to chlorine organic compounds revealed that individuals with AG variation of HTR2A gene are a community with increased sensitivity to chloroform and a risk group for lipid and carbohydrates metabolism disorders. Individual risk of endocrine disorders (ICD: E67.8 excessive nutrition and E66.0 obesity) in these individuals is higher than in general population exposed to chloroform at residence (HQ1.72). Serum serotonin level, that is functionally connected with HTR2A gene, is 1.3 times lower vs. the reference group value.

  20. Nonstructural leaf carbohydrates dynamics of Pinus edulis during drought-induced tree mortality reveal role for carbon metabolism in mortality mechanism

    USGS Publications Warehouse

    Adams, Henry D.; Germino, Matthew J.; Breshears, David D.; Barron-Gafford, Greg A.; Guardiola-Claramonte, Maite; Zou, Chris B.; Huxman, Travis E.

    2013-01-01

    * Reduced foliar NSC during lethal drought indicates a carbon metabolism role in mortality mechanism. Although carbohydrates were not completely exhausted at mortality, temperature differences in starch accumulation timing suggest that carbon metabolism changes are associated with time to death. Drought mortality appears to be related to temperature-dependent carbon dynamics concurrent with increasing hydraulic stress in P. edulis and potentially other similar species.

  1. Metabolic engineering of monoclonal antibody carbohydrates for antibody-drug conjugation.

    PubMed

    Okeley, Nicole M; Toki, Brian E; Zhang, Xinqun; Jeffrey, Scott C; Burke, Patrick J; Alley, Stephen C; Senter, Peter D

    2013-10-16

    The role that carbohydrates play in antibody function and pharmacokinetics has made them important targets for modification. The terminal fucose of the N-linked glycan structure, which has been shown to be involved in modulation of antibody-directed cellular cytotoxicity, is a particularly interesting location for potential modification through incorporation of alternative sugar structures. A library of fucose analogues was evaluated for their ability to incorporate into antibody carbohydrates in place of the native fucose. A number of efficiently incorporated molecules were identified, demonstrating the ability of fucosyltransferase VIII to utilize a variety of non-natural sugars as substrates. Among these structures was a thiolated analogue, 6-thiofucose, which was incorporated into the antibody carbohydrate with good efficiency. This unnatural thio-sugar could then be used for conjugation using maleimide chemistry to produce antibody-drug conjugates with pronounced cytotoxic activities and improved homogeneity compared to drug attachment through hinge disulfides.

  2. [Alpha 1-antitrypsin deficiency with histologic expression of metabolic disease of carbohydrates].

    PubMed

    de la Oliva Senovilla, P; Díaz Fernández, M C; Hierro Llanillo, L; Larrauri Martínez, J; Jara Vega, P

    1989-02-01

    A two months old male affected by alpha-1-AT PiZZ deficiency with severe transient neonatal cholestasis is presented. Two hepatic biopsies were practiced in neonatal period. There was no evidence of PAS positive globules, but an intense univacuolar steatosis and a rossetoid transformation of hepatocytes were observed. Both findings are identical to those found in the histopathologic study of the liver in certain metabolic diseases such as fructosemia and galactosemia. A third biopsy practiced at an age of two years confirmed diagnosis of alpha-1-AT deficit since presence of PAS positive globules was established. It must be pointed out that histopathological findings show great variability among different patients with alpha-1-AT deficit in the neonatal period, as well as the infrequent presence of PAS positive globules in hepatic biopsies of those c during the first months of life.

  3. Effects of growth hormone, insulin-like growth factor I, triiodothyronine, thyroxine, and cortisol on gene expression of carbohydrate metabolic enzymes in sea bream hepatocytes.

    PubMed

    Leung, L Y; Woo, Norman Y S

    2010-11-01

    The present study investigated the regulatory effects of growth hormone (GH), human insulin-like growth factor I (hIGF-I), thyroxine (T(4)), triiodothyronine (T(3)) and cortisol, on mRNA expression of key enzymes involved in carbohydrate metabolism, including glucokinase (GK), glucose-6-phosphatase (G6Pase), glycogen synthase (GS), glycogen phosphorylase (GP) and glucose-6-phosphate dehydrogenase (G6PDH) in hepatocytes isolated from silver sea bream. Genes encoding GK, G6Pase, GS and GP were partially cloned and characterized from silver sea bream liver and real-time PCR assays were developed for the quantification of the mRNA expression profiles of these genes in order to evaluate the potential of these carbohydrate metabolic pathways. GK mRNA level was elevated by GH and hIGF-I, implying that GH-induced stimulation of GK expression may be mediated via IGF-I. GH was found to elevate GS and G6Pase expression, but reduce G6PDH mRNA expression. However, hIGF-I did not affect mRNA levels of GS, G6Pase and G6PDH, suggesting that GH-induced modulation of GS, G6Pase and G6PDH expression levels is direct, and occurs independently of the action of IGF-I. T(3) and T(4) directly upregulated transcript abundance of GK, G6Pase, GS and GP. Cortisol significantly increased transcript amounts of G6Pase and GS but markedly decreased transcript abundance of GK and G6PDH. These changes in transcript abundance indicate that (1) the potential of glycolysis is stimulated by GH and thyroid hormones, but attenuated by cortisol, (2) gluconeogenic and glycogenic potential are augmented by GH, thyroid hormones and cortisol, (3) glycogenolytic potential is upregulated by thyroid hormones but not affected by GH or cortisol, and (4) the potential of the pentose phosphate pathway is attenuated by GH and cortisol but unaffected by thyroid hormones.

  4. Intestinal glucose absorption in calves as affected by different carbohydrate sources.

    PubMed

    Klinger, S; Noci, B; Müller, K; Breves, G

    2013-04-01

    From numerous recent studies, it has been demonstrated that the development of the forestomach system in ruminants and thus microbial carbohydrate fermentation do not exclude the potential of the small intestines for enzymatic carbohydrate digestion and subsequent monosaccharide absorption. However, the role of regulatory nutritional factors is still under discussion. Therefore, we investigated the kinetic parameters of intestinal Na(+) -dependent glucose absorption and SGLT1 expression using isolated brush border membrane vesicles (BBMV) from the jejunum of 10-week-old calves kept on either hay, concentrate or corn silage-based diets in addition to milk replacer. While the maximal transport capacity was significantly higher for concentrate and corn silage-fed animals, SGLT1 protein expression was highest in BBMV isolated from hay-fed animals. This observation differs from the prevalent conception that induction of Na(+) -dependent glucose uptake via SGLT1 is based on an increased number of transporters at the brush border membrane.

  5. Glucose and lipid metabolism in the pancreas of rainbow trout is regulated at the molecular level by nutritional status and carbohydrate intake.

    PubMed

    Polakof, Sergio; Skiba-Cassy, Sandrine; Kaushik, Sadasivam; Seiliez, Iban; Soengas, Jose Luis; Panserat, Stephane

    2012-05-01

    Glucose and lipid metabolism in pancreatic islet organs is poorly characterized. In the present study, using as a model the carnivorous rainbow trout, a glucose-intolerant fish, we assessed mRNA expression levels of several genes involved in glucose and lipid metabolism (including ATP-citrate lyase; carnitine palmitoyltransferase-1 isoforms, CPT; the mitochondrial isoform of the phosphoenolpyrutave carboxykinase, mPEPCK and pyruvate kinase, PK) and glucosensing (glucose transporter type 2, Glut2; glucokinase, GK and the potassium channel, K(ATP)) in Brockmann bodies. We evaluated the response of these parameters to changes in feeding status (food deprived vs. fed fish) as well as to changes in the amount of carbohydrate (dextrin) in the diet. A general inhibition of the glycolytic (including the glucosensing marker GK) and β-oxidation pathways was found when comparing fed versus food-deprived fish. When comparing fish feeding on either low- or high-carbohydrate diets, we found that some genes related to lipid metabolism were more controlled by the feeding status than by the carbohydrate content (fatty acid synthase, CPTs). Findings are discussed in the context of pancreatic regulation of glucose and lipid metabolism in fish, and show that while trout pancreatic metabolism can partially adapt to a high-carbohydrate diet, some of the molecular actors studied seem to be poorly regulated (K(ATP)) and may contribute to the glucose intolerance observed in this species when fed high-carbohydrate diets.

  6. Proteomics Profiling Reveals Carbohydrate Metabolic Enzymes and 14-3-3 Proteins Play Important Roles for Starch Accumulation during Cassava Root Tuberization.

    PubMed

    Wang, Xuchu; Chang, Lili; Tong, Zheng; Wang, Dongyang; Yin, Qi; Wang, Dan; Jin, Xiang; Yang, Qian; Wang, Liming; Sun, Yong; Huang, Qixing; Guo, Anping; Peng, Ming

    2016-01-21

    Cassava is one of the most important root crops as a reliable source of food and carbohydrates. Carbohydrate metabolism and starch accumulation in cassava storage root is a cascade process that includes large amounts of proteins and cofactors. Here, comparative proteomics were conducted in cassava root at nine developmental stages. A total of 154 identified proteins were found to be differentially expressed during starch accumulation and root tuberization. Many enzymes involved in starch and sucrose metabolism were significantly up-regulated, and functional classification of the differentially expressed proteins demonstrated that the majority were binding-related enzymes. Many proteins were took part in carbohydrate metabolism to produce energy. Among them, three 14-3-3 isoforms were induced to be clearly phosphorylated during storage root enlargement. Overexpression of a cassava 14-3-3 gene in Arabidopsis thaliana confirmed that the older leaves of these transgenic plants contained higher sugar and starch contents than the wild-type leaves. The 14-3-3 proteins and their binding enzymes may play important roles in carbohydrate metabolism and starch accumulation during cassava root tuberization. These results not only deepened our understanding of the tuberous root proteome, but also uncovered new insights into carbohydrate metabolism and starch accumulation during cassava root enlargement.

  7. Proteomics Profiling Reveals Carbohydrate Metabolic Enzymes and 14-3-3 Proteins Play Important Roles for Starch Accumulation during Cassava Root Tuberization

    PubMed Central

    Wang, Xuchu; Chang, Lili; Tong, Zheng; Wang, Dongyang; Yin, Qi; Wang, Dan; Jin, Xiang; Yang, Qian; Wang, Liming; Sun, Yong; Huang, Qixing; Guo, Anping; Peng, Ming

    2016-01-01

    Cassava is one of the most important root crops as a reliable source of food and carbohydrates. Carbohydrate metabolism and starch accumulation in cassava storage root is a cascade process that includes large amounts of proteins and cofactors. Here, comparative proteomics were conducted in cassava root at nine developmental stages. A total of 154 identified proteins were found to be differentially expressed during starch accumulation and root tuberization. Many enzymes involved in starch and sucrose metabolism were significantly up-regulated, and functional classification of the differentially expressed proteins demonstrated that the majority were binding-related enzymes. Many proteins were took part in carbohydrate metabolism to produce energy. Among them, three 14-3-3 isoforms were induced to be clearly phosphorylated during storage root enlargement. Overexpression of a cassava 14-3-3 gene in Arabidopsis thaliana confirmed that the older leaves of these transgenic plants contained higher sugar and starch contents than the wild-type leaves. The 14-3-3 proteins and their binding enzymes may play important roles in carbohydrate metabolism and starch accumulation during cassava root tuberization. These results not only deepened our understanding of the tuberous root proteome, but also uncovered new insights into carbohydrate metabolism and starch accumulation during cassava root enlargement. PMID:26791570

  8. Effects of insulin infusion on glucose homeostasis and glucose metabolism in rainbow trout fed a high-carbohydrate diet.

    PubMed

    Polakof, S; Moon, T W; Aguirre, P; Skiba-Cassy, S; Panserat, S

    2010-12-15

    The origin for the poor glucose utilization in carnivorous fish species fed high carbohydrate diets remains under debate. In the present study, we have fed rainbow trout a diet containing 30% carbohydrate for 1 or 5 days. In both cases, fish were implanted with mini-osmotic pumps releasing 0.7 i.u. kg(-1) day(-1) bovine insulin, and mRNA transcripts and the protein phosphorylation status of proteins controlling glycemia and glucose-related metabolism were studied in fish killed 6 h after the last meal. We demonstrate that when the exposure occurs over a short term (30 h), insulin exerts beneficial actions on trout glucose homeostasis, including a lowered glycemia and increased hepatic lipogenic and glycogenic potentials. However, when trout were fed for 5 days, these beneficial actions of insulin infusion were no longer observed. Thus, the increased lipogenic potential observed after one single meal was not present, and this together with the increased glycogenesis and the decreased glucose exported to the blood from the liver explains the lack of hypoglycemic action of insulin. The fact that insulin improved glucose homeostasis when administrated over a short time period implies that endogenous insulin secretion is inadequate in trout to deal with this amount of dietary carbohydrates. Moreover, the fact that a longer exposure to insulin resulted in a reduced response indicates that the rainbow trout is sensitive to insulin, re-enforcing the hypothesis that the hyperglycemia observed following a high carbohydrate meal is an insulin secretion issue rather an insulin action issue.

  9. Metabolic flux in carbohydrate biosynthesis. New methods using stable isotopes, mass spectrometry, and NMR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Structural analysis of carbohydrates involves three parameters: composition, linkage, and conformation, and tends to rely on the various forms of two techniques; mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy. These techniques are enhanced and extended by the use of stable...

  10. Alterations in carbohydrate metabolism and its regulation in PPARalpha null mouse hearts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although a shift from fatty acids (FAs) to carbohydrates (CHOs) is considered beneficial for the diseased heart, it is unclear why subjects with FA beta-oxidation defects are prone to cardiac decompensation under stress conditions. The present study investigated potential alterations in the myocardi...

  11. Sugars, Stable Isotopes, and Spectrometry: New Methods for the Analysis of Carbohydrate Metabolism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Structural analysis of carbohydrates involves three parameters: composition, linkage, and conformation, and tends to rely on the various forms of two techniques; mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy. These techniques are enhanced and extended by the use of stable...

  12. Expression of genes associated with carbohydrate metabolism in cotton stems and roots

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton (Gossypium hirsutum L) is an important crop worldwide that provides fiber for the textile industry. Cotton is a perennial plant that stores starch in stems and roots to provide carbohydrates for growth in subsequent seasons. These reserves are not available to produce seed and fiber when cott...

  13. Adaptive changes in amino acid metabolism permit normal longevity in mice consuming a low-carbohydrate ketogenic diet.

    PubMed

    Douris, Nicholas; Melman, Tamar; Pecherer, Jordan M; Pissios, Pavlos; Flier, Jeffrey S; Cantley, Lewis C; Locasale, Jason W; Maratos-Flier, Eleftheria

    2015-10-01

    Ingestion of very low-carbohydrate ketogenic diets (KD) is associated with weight loss, lowering of glucose and insulin levels and improved systemic insulin sensitivity. However, the beneficial effects of long-term feeding have been the subject of debate. We therefore studied the effects of lifelong consumption of this diet in mice. Complete metabolic analyses were performed after 8 and 80weeks on the diet. In addition we performed a serum metabolomic analysis and examined hepatic gene expression. Lifelong consumption of KD had no effect on morbidity or mortality (KD vs. Chow, 676 vs. 630days) despite hepatic steatosis and inflammation in KD mice. The KD fed mice lost weight initially as previously reported (Kennnedy et al., 2007) and remained lighter and had less fat mass; KD consuming mice had higher levels of energy expenditure, improved glucose homeostasis and higher circulating levels of β-hydroxybutyrate and triglycerides than chow-fed controls. Hepatic expression of the critical metabolic regulators including fibroblast growth factor 21 were also higher in KD-fed mice while expression levels of lipogenic enzymes such as stearoyl-CoA desaturase-1 was reduced. Metabolomic analysis revealed compensatory changes in amino acid metabolism, primarily involving down-regulation of catabolic processes, demonstrating that mice eating KD can shift amino acid metabolism to conserve amino acid levels. Long-term KD feeding caused profound and persistent metabolic changes, the majority of which are seen as health promoting, and had no adverse effects on survival in mice.

  14. Adaptive changes in amino acid metabolism permit normal longevity in mice consuming a low-carbohydrate ketogenic diet

    PubMed Central

    Douris, Nicholas; Melman, Tamar; Pecherer, Jordan M.; Pissios, Pavlos; Flier, Jeffrey S.; Cantley, Lewis C.; Locasale, Jason W.; Maratos-Flier, Eleftheria

    2016-01-01

    Ingestion of very low-carbohydrate ketogenic diets (KD) is associated with weight loss, lowering of glucose and insulin levels and improved systemic insulin sensitivity. However, the beneficial effects of long-term feeding have been the subject of debate. We therefore studied the effects of lifelong consumption of this diet in mice. Complete metabolic analyses were performed after 8 and 80 weeks on the diet. In addition we performed a serum metabolomic analysis and examined hepatic gene expression. Lifelong consumption of KD had no effect on morbidity or mortality (KD vs. Chow, 676 vs. 630 days) despite hepatic steatosis and inflammation in KD mice. The KD fed mice lost weight initially as previously reported (Kennnedy et al., 2007) and remained lighter and had less fat mass; KD consuming mice had higher levels of energy expenditure, improved glucose homeostasis and higher circulating levels of β-hydroxybutyrate and triglycerides than chow-fed controls. Hepatic expression of the critical metabolic regulators including fibroblast growth factor 21 were also higher in KD-fed mice while expression levels of lipogenic enzymes such as stearoyl-CoA desaturase-1 was reduced. Metabolomic analysis revealed compensatory changes in amino acid metabolism, primarily involving down-regulation of catabolic processes, demonstrating that mice eating KD can shift amino acid metabolism to conserve amino acid levels. Long-term KD feeding caused profound and persistent metabolic changes, the majority of which are seen as health promoting, and had no adverse effects on survival in mice. PMID:26170063

  15. Effects of ALA, EPA and DHA in high-carbohydrate, high-fat diet-induced metabolic syndrome in rats.

    PubMed

    Poudyal, Hemant; Panchal, Sunil K; Ward, Leigh C; Brown, Lindsay

    2013-06-01

    We compared the cardiovascular, hepatic and metabolic responses to individual dietary n-3 fatty acids (α-linolenic acid, ALA; eicosapentaenoic acid, EPA; and docosahexaenoic acid, DHA) in a high-carbohydrate, high-fat diet-induced model of metabolic syndrome in rats. Additionally, we measured fatty acid composition of plasma, adipose tissue, liver, heart and skeletal muscle in these rats. The same dosages of ALA and EPA/DHA produced different physiological responses to decrease the risk factors for metabolic syndrome. ALA did not reduce total body fat but induced lipid redistribution away from the abdominal area and favorably improved glucose tolerance, insulin sensitivity, dyslipidemia, hypertension and left ventricular dimensions, contractility, volumes and stiffness. EPA and DHA increased sympathetic activation, reduced the abdominal adiposity and total body fat and attenuated insulin sensitivity, dyslipidemia, hypertension and left ventricular stiffness but not glucose tolerance. However, ALA, EPA and DHA all reduced inflammation in both the heart and the liver, cardiac fibrosis and hepatic steatosis. These effects were associated with complete suppression of stearoyl-CoA desaturase 1 activity. Since the physiological responses to EPA and DHA were similar, it is likely that the effects are mediated by DHA with EPA serving as a precursor. Also, ALA supplementation increased DHA concentrations but induced different physiological responses to EPA and DHA. This result strongly suggests that ALA has independent effects in metabolic syndrome, not relying on its metabolism to DHA.

  16. Rhynchophorus ferrugineus attack affects a group of compounds rather than rearranging Phoenix canariensis metabolic pathways.

    PubMed

    Giovino, Antonio; Martinelli, Federico; Saia, Sergio

    2016-04-01

    The red palm weevil (RPW; Rhynchophorus ferrugineus) is spreading worldwide and severely harming many palm species. However, most studies on RPW focused on insect biology, and little information is available about the plant response to the attack. In the present experiment, we used metabolomics to study the alteration of the leaf metabolome of Phoenix canariensis at initial (1st stage) or advanced (2nd stage) attack by RPW compared with healthy (unattacked) plants. The leaf metabolome significantly varied among treatments. At the 1st stage of attack, plants showed a reprogramming of carbohydrate and organic acid metabolism; in contrast, peptides and lipid metabolic pathways underwent more changes during the 2nd than 1st stage of attack. Enrichment metabolomics analysis indicated that RPW attack mostly affected a particular group of compounds rather than rearranging plant metabolic pathways. Some compounds selectively affected during the 1st rather than 2nd stage (e.g. phenylalanine; tryptophan; cellobiose; xylose; quinate; xylonite; idonate; and iso-threonate; cellobiotol and arbutine) are upstream events in the phenylpropanoid, terpenoid and alkaloid biosynthesis. These compounds could be designated as potential markers of initial RPW attack. However, further investigation is needed to determine efficient early screening methods of RPW attack based on the concentrations of these molecules.

  17. An insulin-like growth factor found in hepatopancreas implicates carbohydrate metabolism of the blue crab Callinectes sapidus.

    PubMed

    Chung, J Sook

    2014-04-01

    Hyperglycemia that is caused by the release of crustacean hyperglycemic hormone (CHH) from the sinus gland to hemolymph is one of the hallmark physiological phenomena, occurring in decapod crustaceans experiencing stressful conditions. However, the mechanism(s) by which such elevated glucose levels return to resting levels is still unknown. Interestingly, noted is a difference in the clearance rate of hemolymph glucose between adult females and adult males of the blue crab, Callinectes sapidus: the former with more rapid clearance than the latter. The presence of an endogenous-insulin-like molecule is suggested in C. sapidus because an injection of bovine insulin, significantly reduces the levels of hemolymph glucose that were previously elevated by emersion stress or the glucose injection. Using 5' and 3' RACE, the full-length cDNA of an insulin-like molecule is isolated from the hepatopancreas of an adult female C. sapidus and shows the same putative sequence of an insulin-like androgenic gland factor (IAG) but differs in 5' and 3' UTR sequences. A knock-down study using five injections of double-stranded RNA of CasIAG-hep (dsRNA-CasIAG-hep, 10μg/injection) over a 10-day period reduces CasIAG-hep expression by ∼50%. The levels of hemolymph glucose are also kept higher in dsRNA-CasIAG-hep injected group than those treated with dsRNA-green fluorescent protein (dsRNA-IAG-hep) or saline. Most importantly, the hepatopancreas of dsRNA-CasIAG-hep injected animals contains amounts of carbohydrate (glucose, trehalose, and glycogen) significantly lower than those of control groups, indicating that the function of CasIAG-hep in carbohydrate metabolism in crustaceans is similar to carbohydrate metabolism in vertebrates.

  18. Hydrogen peroxide functions as a secondary messenger for brassinosteroids-induced CO2 assimilation and carbohydrate metabolism in Cucumis sativus *

    PubMed Central

    Jiang, Yu-ping; Cheng, Fei; Zhou, Yan-hong; Xia, Xiao-jian; Mao, Wei-hua; Shi, Kai; Chen, Zhi-xiang; Yu, Jing-quan

    2012-01-01

    Brassinosteroids (BRs) are potent regulators of photosynthesis and crop yield in agricultural crops; however, the mechanism by which BRs increase photosynthesis is not fully understood. Here, we show that foliar application of 24-epibrassinolide (EBR) resulted in increases in CO2 assimilation, hydrogen peroxide (H2O2) accumulation, and leaf area in cucumber. H2O2 treatment induced increases in CO2 assimilation whilst inhibition of the H2O2 accumulation by its generation inhibitor or scavenger completely abolished EBR-induced CO2 assimilation. Increases of light harvesting due to larger leaf areas in EBR- and H2O2-treated plants were accompanied by increases in the photochemical efficiency of photosystem II (ΦPSII) and photochemical quenching coefficient (q P). EBR and H2O2 both activated carboxylation efficiency of ribulose-1,5-bisphosphate oxygenase/carboxylase (Rubisco) from analysis of CO2 response curve and in vitro measurement of Rubisco activities. Moreover, EBR and H2O2 increased contents of total soluble sugar, sucrose, hexose, and starch, followed by enhanced activities of sugar metabolism such as sucrose phosphate synthase, sucrose synthase, and invertase. Interestingly, expression of transcripts of enzymes involved in starch and sugar utilization were inhibited by EBR and H2O2. However, the effects of EBR on carbohydrate metabolisms were reversed by the H2O2 generation inhibitor diphenyleneodonium (DPI) or scavenger dimethylthiourea (DMTU) pretreatment. All of these results indicate that H2O2 functions as a secondary messenger for EBR-induced CO2 assimilation and carbohydrate metabolism in cucumber plants. Our study confirms that H2O2 mediates the regulation of photosynthesis by BRs and suggests that EBR and H2O2 regulate Calvin cycle and sugar metabolism via redox signaling and thus increase the photosynthetic potential and yield of crops. PMID:23024048

  19. Hydrogen peroxide functions as a secondary messenger for brassinosteroids-induced CO2 assimilation and carbohydrate metabolism in Cucumis sativus.

    PubMed

    Jiang, Yu-ping; Cheng, Fei; Zhou, Yan-hong; Xia, Xiao-jian; Mao, Wei-hua; Shi, Kai; Chen, Zhi-xiang; Yu, Jing-quan

    2012-10-01

    Brassinosteroids (BRs) are potent regulators of photosynthesis and crop yield in agricultural crops; however, the mechanism by which BRs increase photosynthesis is not fully understood. Here, we show that foliar application of 24-epibrassinolide (EBR) resulted in increases in CO(2) assimilation, hydrogen peroxide (H(2)O(2)) accumulation, and leaf area in cucumber. H(2)O(2) treatment induced increases in CO(2) assimilation whilst inhibition of the H(2)O(2) accumulation by its generation inhibitor or scavenger completely abolished EBR-induced CO(2) assimilation. Increases of light harvesting due to larger leaf areas in EBR- and H(2)O(2)-treated plants were accompanied by increases in the photochemical efficiency of photosystem II (Φ(PSII)) and photochemical quenching coefficient (q(P)). EBR and H(2)O(2) both activated carboxylation efficiency of ribulose-1,5-bisphosphate oxygenase/carboxylase (Rubisco) from analysis of CO(2) response curve and in vitro measurement of Rubisco activities. Moreover, EBR and H(2)O(2) increased contents of total soluble sugar, sucrose, hexose, and starch, followed by enhanced activities of sugar metabolism such as sucrose phosphate synthase, sucrose synthase, and invertase. Interestingly, expression of transcripts of enzymes involved in starch and sugar utilization were inhibited by EBR and H(2)O(2). However, the effects of EBR on carbohydrate metabolisms were reversed by the H(2)O(2) generation inhibitor diphenyleneodonium (DPI) or scavenger dimethylthiourea (DMTU) pretreatment. All of these results indicate that H(2)O(2) functions as a secondary messenger for EBR-induced CO(2) assimilation and carbohydrate metabolism in cucumber plants. Our study confirms that H(2)O(2) mediates the regulation of photosynthesis by BRs and suggests that EBR and H(2)O(2) regulate Calvin cycle and sugar metabolism via redox signaling and thus increase the photosynthetic potential and yield of crops.

  20. Olive leaf extract attenuates cardiac, hepatic, and metabolic changes in high carbohydrate-, high fat-fed rats.

    PubMed

    Poudyal, Hemant; Campbell, Fiona; Brown, Lindsay

    2010-05-01

    Olive oil, an important component of the Mediterranean diet, produces cardioprotective effects, probably due to both oleic acid and the polyphenols such as oleuropein and hydroxytyrosol. Our aim in this study was to assess whether a polyphenol-enriched extract from the leaves of Olea europaea L. with oleuropein as the major component attenuated the cardiovascular, hepatic, and metabolic signs of a high-carbohydrate, high-fat (HCHF) diet (carbohydrate, 52%; fat, 24%, 25% fructose in drinking water) in rats. Male Wistar rats were fed either a cornstarch diet (CS) or a HCHF diet for a total of 16 wk. Diets of the treatment groups [CS+olive leaf extract (OLE) and HCHF+OLE] were supplemented with 3% OLE after 8 wk of being fed their respective CS or HCHF diets for a further 8 wk. After 16 wk, HCHF rats developed signs of metabolic syndrome, including elevated abdominal and hepatic fat deposition, collagen deposition in heart and liver, cardiac stiffness, and oxidative stress markers (plasma malondialdehyde and uric acid concentrations), with diminished aortic ring reactivity, abnormal plasma lipid profile, impaired glucose tolerance, and hypertension. Compared with HCHF rats, those in the HCHF+OLE group had improved or normalized cardiovascular, hepatic, and metabolic signs with the exception of elevated blood pressure. These results strongly suggest that an OLE containing polyphenols such as oleuropein and hydroxytyrosol reverses the chronic inflammation and oxidative stress that induces the cardiovascular, hepatic, and metabolic symptoms in this rat model of diet-induced obesity and diabetes without changing blood pressure.

  1. Randomized controlled study of the influence of two low estrogen dose oral contraceptives containing gestodene or desogestrel on carbohydrate metabolism.

    PubMed

    Lüdicke, Frank; Gaspard, Ulysse J; Demeyer, Fabienne; Scheen, A; Lefebvre, P

    2002-12-01

    This study compared the impact on carbohydrate metabolism of two combinedoral contraceptives (COCs). This open-label, single-center trial enrolled participants for a total of 15 cycles. Thirty-six women were randomized to receive either 20 microg ethinyl estradiol (EE) and 75 microg gestodene (GSD) or 20 microg ethinyl estradiol and 150 microg desogestrel (DSG) daily for 21 days out of 28. A glucose tolerance test was performed at baseline and cycles 6 and 13. The area under the curve (AUC) for glucose increased in both study groups. The change was statistically significant (p = 0.036) for the 20 EE/75 GSD group at cycle 6 versus baseline. Fasting blood glucose at cycle 13 was significantly (p < 0.01) higher for both treatment groups compared to baseline. No changes were found for fasting insulin and fasting C-peptide levels or for the AUCs of insulin or C-peptide. Both regimens were well tolerated. Gestodene and desogestrel in combination with 20-microg ethinyl estradiol induce similar changes in carbohydrate metabolism which are smaller than those described earlier for COCs containing higher estrogen doses or more androgenic progestins such as levonorgestrel.

  2. Investigation of Carbohydrate Metabolism and Transport in Castor Bean Seedlings by Cyclic JCross Polarization Imaging and Spectroscopy

    NASA Astrophysics Data System (ADS)

    Heidenreich, M.; Köckenberger, W.; Kimmich, R.; Chandrakumar, N.; Bowtell, R.

    1998-05-01

    NMR experiments using13C-labeled compounds offer the possibility of noninvasive monitoring of carbohydrate transport and metabolism in living plants, but are usually hampered by the low sensitivity of the13C nucleus. The problem of low sensitivity can be overcome by using the cyclicJcross polarization (CYCLCROP) technique, which allows the indirect detection of13C nuclei coupled to1H nuclei with the high NMR sensitivity of protons. We report here on methods for imaging and spectroscopy based on the CYCLCROP technique, and their use in the firstin vivoNMR study of carbohydrate transport and metabolism in castor bean seedlings (Ricinus communis L.). Comprehensive acquisition strategies for the various NMR methods are given, including the procedure for setting up the experiments. In addition, a full analysis of the effect of relaxation on the signals generated from smallJ-coupled spin systems by the CYCLCROP sequence is given, and the high sensitivity of the sequence is demonstrated. In thein vivostudy of six-day-old castor bean seedlings, we were able to measure the uptake of labeled hexoses, supplied in solution to the cotyledons, and their conversion to sucrose, as well as the transport of this sucrose in the vascular bundles. Images of the actual distribution of labeled sucrose in the hypocotyl of the seedling have also been obtained. The resulting data show some evidence for a preferential incorporation of labeled fructose in the process of sucrose synthesis, which decreases with the time of incubation.

  3. Mathematical modeling of the central carbohydrate metabolism in Arabidopsis reveals a substantial regulatory influence of vacuolar invertase on whole plant carbon metabolism.

    PubMed

    Nägele, Thomas; Henkel, Sebastian; Hörmiller, Imke; Sauter, Thomas; Sawodny, Oliver; Ederer, Michael; Heyer, Arnd G

    2010-05-01

    A mathematical model representing metabolite interconversions in the central carbohydrate metabolism of Arabidopsis (Arabidopsis thaliana) was developed to simulate the diurnal dynamics of primary carbon metabolism in a photosynthetically active plant leaf. The model groups enzymatic steps of central carbohydrate metabolism into blocks of interconverting reactions that link easily measurable quantities like CO(2) exchange and quasi-steady-state levels of soluble sugars and starch. When metabolite levels that fluctuate over diurnal cycles are used as a basic condition for simulation, turnover rates for the interconverting reactions can be calculated that approximate measured metabolite dynamics and yield kinetic parameters of interconverting reactions. We used experimental data for Arabidopsis wild-type plants, accession Columbia, and a mutant defective in vacuolar invertase, AtbetaFruct4, as input data. Reducing invertase activity to mutant levels in the wild-type model led to a correct prediction of increased sucrose levels. However, additional changes were needed to correctly simulate levels of hexoses and sugar phosphates, indicating that invertase knockout causes subsequent changes in other enzymatic parameters. Reduction of invertase activity caused a decline in photosynthesis and export of reduced carbon to associated metabolic pathways and sink organs (e.g. roots), which is in agreement with the reported contribution of vacuolar invertase to sink strength. According to model parameters, there is a role for invertase in leaves, where futile cycling of sucrose appears to have a buffering effect on the pools of sucrose, hexoses, and sugar phosphates. Our data demonstrate that modeling complex metabolic pathways is a useful tool to study the significance of single enzyme activities in complex, nonintuitive networks.

  4. Identification of the first insulin-like peptide in the disease vector Rhodnius prolixus: Involvement in metabolic homeostasis of lipids and carbohydrates.

    PubMed

    Defferrari, Marina S; Orchard, Ian; Lange, Angela B

    2016-03-01

    Insulin-like peptides (ILPs) are functional analogs of insulin and have been identified in many insect species. The insulin cell signaling pathway is a conserved regulator of metabolism, and in insects, as well as in other animals, can modulate physiological functions associated with the metabolism of lipids and carbohydrates. In the present study, we have identified the first ILP from the Rhodnius prolixus genome (termed Rhopr-ILP) and investigated its involvement in energy metabolism of unfed and recently fed fifth instars. We have cloned the cDNA sequence and analyzed the expression profile of the transcript, which is predominantly present in neurosecretory cells in the brain, similar to other insect ILPs. Using RNAi, we have reduced the expression of this peptide transcript by 90% and subsequently measured the carbohydrate and lipid levels in the hemolymph, fat body and leg muscles. Reduced levels of Rhopr-ILP transcript induced increased carbohydrate and lipid levels in the hemolymph and increased lipid content in the fat body, in unfed insects and recently fed insects. Also their fat bodies displayed enlarged lipid droplets within the cells. On the other hand, the carbohydrate content in the fat body and in the leg muscles of unfed insects were decreased when compared to control insects. Our results indicate that Rhopr-ILP is a modulator of lipid and carbohydrate metabolism, probably through signaling the presence of available energy and nutrients in the hemolymph.

  5. Effects of fat on insulin-stimulated carbohydrate metabolism in normal men.

    PubMed Central

    Boden, G; Jadali, F; White, J; Liang, Y; Mozzoli, M; Chen, X; Coleman, E; Smith, C

    1991-01-01

    We have examined the onset and duration of the inhibitory effect of an intravenous infusion of lipid/heparin on total body carbohydrate and fat oxidation (by indirect calorimetry) and on glucose disappearance (with 6,6 D2-glucose and gas chromatography-mass spectrometry) in healthy men during euglycemic hyperinsulinemia. Glycogen synthase activity and concentrations of acetyl-CoA, free CoA-SH, citrate, and glucose-6-phosphate were measured in muscle biopsies obtained before and after insulin/lipid and insulin/saline infusions. Lipid increased insulin-inhibited fat oxidation (+40%) and decreased insulin-stimulated carbohydrate oxidation (-63%) within 1 h. These changes were associated with an increase (+489%) in the muscle acetyl-CoA/free CoA-SH ratio. Glucose disappearance did not decrease until 2-4 h later (-55%). This decrease was associated with a decrease in muscle glycogen synthase fractional velocity (-82%). The muscle content of citrate and glucose-6-phosphate did not change. We concluded that, during hyperinsulinemia, lipid promptly replaced carbohydrate as fuel for oxidation in muscle and hours later inhibited glucose uptake, presumably by interfering with muscle glycogen formation. PMID:1885781

  6. AMP-activated protein kinase: an emerging drug target to regulate imbalances in lipid and carbohydrate metabolism to treat cardio-metabolic diseases

    PubMed Central

    Srivastava, Rai Ajit K.; Pinkosky, Stephen L.; Filippov, Sergey; Hanselman, Jeffrey C.; Cramer, Clay T.; Newton, Roger S.

    2012-01-01

    The adenosine monophosphate-activated protein kinase (AMPK) is a metabolic sensor of energy metabolism at the cellular as well as whole-body level. It is activated by low energy status that triggers a switch from ATP-consuming anabolic pathways to ATP-producing catabolic pathways. AMPK is involved in a wide range of biological activities that normalizes lipid, glucose, and energy imbalances. These pathways are dysregulated in patients with metabolic syndrome (MetS), which represents a clustering of major cardiovascular risk factors including diabetes, lipid abnormalities, and energy imbalances. Clearly, there is an unmet medical need to find a molecule to treat alarming number of patients with MetS. AMPK, with multifaceted activities in various tissues, has emerged as an attractive drug target to manage lipid and glucose abnormalities and maintain energy homeostasis. A number of AMPK activators have been tested in preclinical models, but many of them have yet to reach to the clinic. This review focuses on the structure-function and role of AMPK in lipid, carbohydrate, and energy metabolism. The mode of action of AMPK activators, mechanism of anti-inflammatory activities, and preclinical and clinical findings as well as future prospects of AMPK as a drug target in treating cardio-metabolic disease are discussed. PMID:22798688

  7. Effects of grafting with pumpkin rootstock on carbohydrate metabolism in cucumber seedlings under Ca(NO3)2 stress.

    PubMed

    Xing, Wen-wen; Li, Lin; Gao, Pan; Li, He; Shao, Qiao-sai; Shu, Sheng; Sun, Jin; Guo, Shi-rong

    2015-02-01

    This study investigated the effects of grafting on the carbohydrate status and the enzymes of carbohydrate metabolism in self-grafted and grafted cucumber seedlings using the salt-tolerant pumpkin rootstock 'Qingzhen 1' (Cucurbita maxima × Cucurbita moschata) under 80 mM Ca(NO3)2 stress for 6 d. The growth of self-grafted seedlings was significantly inhibited after the treatment of Ca(NO3)2 stress, whereas the inhibition of growth was alleviated in pumpkin rootstock-grafted seedlings. Ca(NO3)2 stress increased the contents of the total soluble sugar, sucrose and fructose, but decreased the starch content in rootstock-grafted leaves. However, compared with self-grafted plants, rootstock-grafted seedlings were observed with a higher content of sucrose and total soluble sugar (TSS) under salt stress. Rootstock-grafted seedlings exhibited higher activities of acid invertase (AI), neutral invertase (NI) and phosphate sucrose synthase (SPS) of sucrose metabolism in leaves than that of self-grafted seedlings under salinity. Moreover, the activities of fructokinase (FK), hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) of glycolysis were maintained at a higher level in leaves of rootstock-grafted seedlings after Ca(NO3)2 stress. Additionally, rootstock-grafting decrease the high percentage enhancement of key enzymes gene expression in glycolysis in the scion leaves of cucumber seedlings induced by salt stress. These results suggest that the rootstock-grafting improved salt tolerance, which might play a role in elevated sucrose metabolism and a glycolytic pathway regulated by the pumpkin rootstock.

  8. Acarbose, lente carbohydrate, and prebiotics promote metabolic health and longevity by stimulating intestinal production of GLP-1

    PubMed Central

    McCarty, Mark F; DiNicolantonio, James J

    2015-01-01

    The α-glucosidase inhibitor acarbose, which slows carbohydrate digestion and blunts postprandial rises in plasma glucose, has long been used to treat patients with type 2 diabetes or glucose intolerance. Like metformin, acarbose tends to aid weight control, postpone onset of diabetes and decrease risk for cardiovascular events. Acarbose treatment can favourably affect blood pressure, serum lipids, platelet aggregation, progression of carotid intima-media thickness and postprandial endothelial dysfunction. In mice, lifetime acarbose feeding can increase median and maximal lifespan—an effect associated with increased plasma levels of fibroblast growth factor 21 (FGF21) and decreased levels of insulin-like growth factor-I (IGF-I). There is growing reason to suspect that an upregulation of fasting and postprandial production of glucagon-like peptide-1 (GLP-1)—stemming from increased delivery of carbohydrate to L cells in the distal intestinal tract—is largely responsible for the versatile health protection conferred by acarbose. Indeed, GLP-1 exerts protective effects on vascular endothelium, the liver, the heart, pancreatic β cells, and the brain which can rationalise many of the benefits reported with acarbose. And GLP-1 may act on the liver to modulate its production of FGF21 and IGF-I, thereby promoting longevity. The benefits of acarbose are likely mimicked by diets featuring slowly-digested ‘lente’ carbohydrate, and by certain nutraceuticals which can slow carbohydrate absorption. Prebiotics that promote colonic generation of short-chain fatty acids represent an alternative strategy for boosting intestinal GLP-1 production. The health benefits of all these measures presumably would be potentiated by concurrent use of dipeptidyl peptidase 4 inhibitors, which slow the proteolysis of GLP-1 in the blood. PMID:25685364

  9. Abnormal folate metabolism in foetuses affected by neural tube defects.

    PubMed

    Dunlevy, Louisa P E; Chitty, Lyn S; Burren, Katie A; Doudney, Kit; Stojilkovic-Mikic, Taita; Stanier, Philip; Scott, Rosemary; Copp, Andrew J; Greene, Nicholas D E

    2007-04-01

    Folic acid supplementation can prevent many cases of neural tube defects (NTDs), whereas suboptimal maternal folate status is a risk factor, suggesting that folate metabolism is a key determinant of susceptibility to NTDs. Despite extensive genetic analysis of folate cycle enzymes, and quantification of metabolites in maternal blood, neither the protective mechanism nor the relationship between maternal folate status and susceptibility are understood in most cases. In order to investigate potential abnormalities in folate metabolism in the embryo itself, we derived primary fibroblastic cell lines from foetuses affected by NTDs and subjected them to the dU suppression test, a sensitive metabolic test of folate metabolism. Significantly, a subset of NTD cases exhibited low scores in this test, indicative of abnormalities in folate cycling that may be causally linked to the defect. Susceptibility to NTDs may be increased by suppression of the methylation cycle, which is interlinked with the folate cycle. However, reduced efficacy in the dU suppression test was not associated with altered abundance of the methylation cycle intermediates, s-adenosylmethionine and s-adenosylhomocysteine, suggesting that a methylation cycle defect is unlikely to be responsible for the observed abnormality of folate metabolism. Genotyping of samples for known polymorphisms in genes encoding folate-associated enzymes did not reveal any correlation between specific genotypes and the observed abnormalities in folate metabolism. These data suggest that as yet unrecognized genetic variants result in embryonic abnormalities of folate cycling that may be causally related to NTDs.

  10. Carbohydrate intake, obesity, metabolic syndrome and cancer risk? A two-part systematic review and meta-analysis protocol to estimate attributability

    PubMed Central

    Sartorius, B; Sartorius, K; Aldous, C; Madiba, T E; Stefan, C; Noakes, T

    2016-01-01

    Introduction Linkages between carbohydrates, obesity and cancer continue to demonstrate conflicting results. Evidence suggests inconclusive direct linkages between carbohydrates and specific cancers. Conversely, obesity has been strongly linked to a wide range of cancers. The purpose of the study is to explore linkages between carbohydrate intake and cancer types using a two-step approach. First the study will evaluate the linkages between carbohydrate intake and obesity, potentially stratified by metabolic syndrome status. Second, the estimated attributable fraction of obesity ascribed to carbohydrate intake will be multiplied against obesity attributable fractions for cancer types to give estimated overall attributable fraction for carbohydrate versus cancer type. Methods and analysis We will perform a comprehensive search to identify all possible published and unpublished studies that have assessed risk factors for obesity including dietary carbohydrate intake. Scientific databases, namely PubMed MEDLINE, EMBASE, EBSCOhost and ISI Web of Science will be searched. Following study selection, paper/data acquisition, and data extraction and synthesis, we will appraise the quality of studies and risk of bias, as well as assess heterogeneity. Meta-weighted attributable fractions of obesity due to carbohydrate intake will be estimated after adjusting for other potential confounding factors (eg, physical inactivity, other dietary intake). Furthermore, previously published systematic reviews assessing the cancer-specific risk associated with obesity will also be drawn. These estimates will be linked with the attributability of carbohydrate intake in part 1 to estimate the cancer-specific burden that can be attributed to dietary carbohydrates. This systematic review protocol has been developed according to the ‘Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) 2015’. Ethics and dissemination The current study will be based on

  11. Phosphate absorption and efflux of three ectomycorrhizal fungi as affected by external phosphate, cation and carbohydrate concentrations.

    PubMed

    Bücking, Heike

    2004-06-01

    A prerequisite for symbiotic phosphate transfer in an ectomycorrhizal (ECM) association is hypothesized to be conditions in the interface between both symbiotic partners, that either promote the release of inorganic phosphate (P) from the Hartig net into the interfacial apoplast and/or decrease the fungal reabsorption from this location. To get more information about conditions, which might be involved in the regulation of P efflux or P reabsorption, the effect of various external conditions on 33P-orthophosphate (33P) uptake or efflux by axenic cultures of the ECM basidiomycetes Hebeloma crustliniforme, Amanita muscaria and Laccaria laccata was analysed. In short-time experiments the following external conditions were analysed: an external supply of (1) P in the preculture, (2) cations (0.1-100 mM K, 0.1-50 mM Na, Mg and Ca), and (3) carbohydrates (0.5-50 mM glucose, fructose or sucrose). The P absorption was generally reduced in cultures previously supplied with an abundant P supply and with increased P concentrations in their tissues. The P uptake was also affected by an external supply of cations, whereas carbohydrates had only a slight effect. Compared to Na, Mg and Ca, the P absorption by H. crustuliniforme and L. laccata was increased by 0.1 mM K in the labelling solution but decreased after a supply of 100 mM K and then did not differ from the other cation treatments. Compared to other cations, an addition of 50 mM Ca led to a decrease of P absorption by A. muscaria, whereas 50 mM Mg increased the P uptake by H. crustuliniforme. The P efflux from the fungi was affected by both the cation and carbohydrate concentration of the bathing solution. High concentrations of the monovalent cations K and Na (5 mM or 50 mM) in the bathing solution increased the P efflux by H. crustuliniforme (only Na) and L. laccata (K and Na), but had little effects on A. muscaria. By contrast, the same concentrations of the divalent cation Mg reduced the P efflux from all fungal

  12. Antidiabetic efficacy of citronellol, a citrus monoterpene by ameliorating the hepatic key enzymes of carbohydrate metabolism in streptozotocin-induced diabetic rats.

    PubMed

    Srinivasan, Subramani; Muruganathan, Udaiyar

    2016-04-25

    Diabetes mellitus is a clinically complex disease characterized by chronic hyperglycemia with metabolic disturbances. During diabetes, endogenous hepatic glucose production is increased as a result of impaired activities of the key enzymes of carbohydrate metabolism. The purpose of the present study was to evaluate the antidiabetic efficacy of citronellol, a citrus monoterpene in streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced by a single intraperitoneal injection of STZ (40 mg/kg b.w). STZ induced diabetic rats received citronellol orally at the doses of 25, 50, and 100 mg/kg b.w for 30 days. In this study the levels of plasma glucose, insulin, hemoglobin (Hb), glycated hemoglobin (HbA1C), glycogen, and the activities of carbohydrate metabolic enzymes, liver and kidney markers were evaluated. Oral administration of citronellol (50 mg/kg) for 30 days dose dependently improved the levels of insulin, Hb and hepatic glycogen with significant decrease in glucose and HbA1C levels. The altered activities of carbohydrate metabolic enzymes, hepatic and kidney markers were restored to near normal. Citronellol supplement was found to be effective in preserving the normal histological appearance of hepatic cells and insulin-positive β-cells in STZ-rats. Our results suggest that administration of citronellol attenuates the hyperglycemia in the STZ-induced diabetic rats by ameliorating the key carbohydrate metabolic enzymes and could be developed as a functional and nutraceutical ingredient in combating diabetes mellitus.

  13. Carbohydrate and Caffeine Mouth Rinses Do Not Affect Maximum Strength and Muscular Endurance Performance.

    PubMed

    Clarke, Neil D; Kornilios, Evangelos; Richardson, Darren L

    2015-10-01

    Oral carbohydrate (CHO) rinsing has beneficial effects on endurance performance and caffeine (CAF) mouth rinsing either independently or in conjunction with CHO may enhance sprinting performance. However, the effects of CHO and CAF mouth rinses on resistance exercise have not been examined previously. The purpose of this study was to investigate the effects of CHO and CAF rinsing on maximum strength and muscular endurance performance. Fifteen recreationally resistance-trained males completed an exercise protocol, which involved a 1 repetition maximum (RM) bench press followed by 60% of their 1RM to failure in a double-blind, randomized, counterbalanced crossover design. Before exercise, 25 ml of a 6% (15 g; 0.20 ± 0.02 g·kg(-1)) CHO, 1.2% (300 mg; 3.9 ± 0.3 mg·kg(-1)) CAF, carbohydrate with caffeine (C + C) solutions, or water (placebo; PLA) were rinsed for 10 seconds. During the remaining session, no solution was rinsed (control; CON). All solutions were flavored with (200 mg) sucralose. Felt arousal was recorded pre- and post-rinse, and rating of perceived exertion (RPE) was recorded immediately after the repetitions to failure. There were no significant differences in 1RM (p = 0.808; ηp(2)= 0.02), the number of repetitions performed (p = 0.682; ηp(2)= 0.03), or the total exercise volume (p = 0.482; ηp(2)= 0.03) between conditions. Rating of perceived exertion was similar for all trials (p = 0.330; ηp(2)= 0.08), whereas Felt arousal increased as a consequence of rinsing (p = 0.001; ηp(2)= 0.58), but was not different between trials (p = 0.335; ηp(2)= 0.08). These results suggest that rinsing with a CHO and CAF solution either independently or combined has no significant effect on maximum strength or muscular endurance performance.

  14. Regulation of Lactobacillus plantarum contamination on the carbohydrate and energy related metabolisms of Saccharomyces cerevisiae during bioethanol fermentation.

    PubMed

    Dong, Shi-Jun; Lin, Xiang-Hua; Li, Hao

    2015-11-01

    During the industrial bioethanol fermentation, Saccharomyces cerevisiae cells are often stressed by bacterial contaminants, especially lactic acid bacteria. Generally, lactic acid bacteria contamination can inhibit S. cerevisiae cell growth through secreting lactic acid and competing with yeast cells for micronutrients and living space. However, whether are there still any other influences of lactic acid bacteria on yeast or not? In this study, Lactobacillus plantarum ATCC 8014 was co-cultivated with S. cerevisiae S288c to mimic the L. plantarum contamination in industrial bioethanol fermentation. The contaminative L. plantarum-associated expression changes of genes involved in carbohydrate and energy related metabolisms in S. cerevisiae cells were determined by quantitative real-time polymerase chain reaction to evaluate the influence of L. plantarum on carbon source utilization and energy related metabolism in yeast cells during bioethanol fermentation. Contaminative L. plantarum influenced the expression of most of genes which are responsible for encoding key enzymes involved in glucose related metabolisms in S. cerevisiae. Specific for, contaminated L. plantarum inhibited EMP pathway but promoted TCA cycle, glyoxylate cycle, HMP, glycerol synthesis pathway, and redox pathway in S. cerevisiae cells. In the presence of L. plantarum, the carbon flux in S. cerevisiae cells was redistributed from fermentation to respiratory and more reducing power was produced to deal with the excess NADH. Moreover, L. plantarum contamination might confer higher ethanol tolerance to yeast cells through promoting accumulation of glycerol. These results also highlighted our knowledge about relationship between contaminative lactic acid bacteria and S. cerevisiae during bioethanol fermentation.

  15. Carbohydrate and amino acid metabolism in fasting and aestivating African lungfish (Protopterus dolloi).

    PubMed

    Frick, Natasha Therese; Bystriansky, Jason Scott; Ip, Yuen Kwong; Chew, Shit Fun; Ballantyne, James Stuart

    2008-09-01

    The potential importance of carbohydrates and amino acids as fuels during periods of fasting and aestivation in the African lungfish, Protopterus dolloi, were examined. No significant decreases in tissue glycogen levels were observed following 60 days of fasting or aestivation, suggesting lungfish may undergo 'glycogen sparing'. Yet glycogenolysis may be important during aestivation based on the differing responses of two flux-generating enzymes of the glycolytic pathway, hexokinase (HK) and pyruvate kinase (PK). PK is required for glycogen breakdown whereas HK is not. HK activity is significantly down-regulated in the heart and gill tissues during aestivation, while PK activity is sustained. The significant negative correlation between the activity of HK and glucose levels in the heart of aestivating lungfish suggests HK may be regulated by glucose concentrations. There was no indication of anaerobic glycolytic flux during aestivation as lactate did not accumulate in any of the tissues examined, and no significant induction of lactate dehydrogenase (LDH)activity was observed. The increase in glutamate dehydrogenase (GDH) and aspartate aminotransferase (Asp-AT) activities in the liver of aestivating P. dolloi suggests some energy may be obtained via increased aminoacid catabolism, leading to the generation of tricarboxylic acid (TCA) cycle intermediates. These findings indicate the importance of both carbohydrate and amino acid fuel stores during aestivation in aphylogenetically ancient, air-breathing fish.

  16. Influence of Ramadan-type fasting on carbohydrate metabolism, brush border membrane enzymes and phosphate transport in rat kidney used as a model.

    PubMed

    Salim, Samina; Farooq, Neelam; Priyamvada, Shubha; Asghar, Mohammad; Khundmiri, Syed Jalal; Khan, Samia; Khan, Farah; Yusufi, Ahad Noor Khan

    2007-11-01

    Ramadan fasting is a unique model of fasting in which Muslims the world over abstain from food and water from dawn to sunset for 1 month. We hypothesized that this model of prolonged intermittent fasting would result in specific adaptive alterations in rat kidney to keep a positive balance of metabolites and inorganic phosphate (Pi). The effect of Ramadan-type fasting was studied on enzymes of carbohydrate metabolism and brush border membrane (BBM) and BBM uptake of 32Pi in different renal tissue zones in the rat model. Rats were fasted (12 h) and then re-fed (12 h) daily for 30 d similar to human Ramadan fasting. Ramadan-type fasting resulted in increased serum Pi and phospholipids, whereas Pi clearance decreased. Serum creatinine and its clearance were not affected. Fasting caused a significant decrease in the activities of lactate and malate dehydrogenases, glucose-6-phosphatase and fructose-1,6-bisphosphatase, both in the renal cortex and medulla. However, the activity of glucose-6-phosphate dehydrogenase profoundly increased but that of malic enzyme decreased. The activities of alkaline phosphatase and gamma-glutamyl transpeptidase in BBM decreased, whereas transport of 32Pi significantly increased. The decrease in enzyme activities and increase in 32Pi transport were due to alterations of both maximal velocities and relative affinities. The results indicate that Ramadan-type fasting caused specific metabolic alterations with enhanced Pi conservation in different kidney tissues in a rat model used for Ramadan fasting in man.

  17. Winter warming delays dormancy release, advances budburst, alters carbohydrate metabolism and reduces yield in a temperate shrub.

    PubMed

    Pagter, Majken; Andersen, Uffe Brandt; Andersen, Lillie

    2015-03-23

    Global climate models predict an increase in the mean surface air temperature, with a disproportionate increase during winter. Since temperature is a major driver of phenological events in temperate woody perennials, warming is likely to induce changes in a range of these events. We investigated the impact of slightly elevated temperatures (+0.76 °C in the air, +1.35 °C in the soil) during the non-growing season (October-April) on freezing tolerance, carbohydrate metabolism, dormancy release, spring phenology and reproductive output in two blackcurrant (Ribes nigrum) cultivars to understand how winter warming modifies phenological traits in a woody perennial known to have a large chilling requirement and to be sensitive to spring frost. Warming delayed dormancy release more in the cultivar 'Narve Viking' than in the cultivar 'Titania', but advanced budburst and flowering predominantly in 'Titania'. Since 'Narve Viking' has a higher chilling requirement than 'Titania', this indicates that, in high-chilling-requiring genotypes, dormancy responses may temper the effect of warming on spring phenology. Winter warming significantly reduced fruit yield the following summer in both cultivars, corroborating the hypothesis that a decline in winter chill may decrease reproductive effort in blackcurrant. Elevated winter temperatures tended to decrease stem freezing tolerance during cold acclimation and deacclimation, but it did not increase the risk of freeze-induced damage mid-winter. Plants at elevated temperature showed decreased levels of sucrose in stems of both cultivars and flower buds of 'Narve Viking', which, in buds, was associated with increased concentrations of glucose and fructose. Hence, winter warming influences carbohydrate metabolism, but it remains to be elucidated whether decreased sucrose levels account for any changes in freezing tolerance. Our results demonstrate that even a slight increase in winter temperature may alter phenological traits in

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

    PubMed

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

    2012-01-01

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

  19. Tyrosol, a phenolic compound, ameliorates hyperglycemia by regulating key enzymes of carbohydrate metabolism in streptozotocin induced diabetic rats.

    PubMed

    Chandramohan, Ramasamy; Pari, Leelavinothan; Rathinam, Ayyasamy; Sheikh, Bashir Ahmad

    2015-03-05

    The present study was designed to evaluate the effects of tyrosol, a phenolic compound, on the activities of key enzymes of carbohydrate metabolism in the control and streptozotocin-induced diabetic rats. Diabetes mellitus was induced in rats by a single intraperitoneal injection of streptozotocin (40 mg/kg body weight). Experimental rats were administered tyrosol 1 ml intra gastrically at the doses of 5, 10 and 20mg/kg body weight and glibenclamide 1 ml at a dose of 600 μg/kg body weight once a day for 45 days. At the end of the experimental period, diabetic control rats exhibited significant (p<0.05) increase in plasma glucose, glycosylated hemoglobin with significant (p<0.05) decrease in plasma insulin, total hemoglobin and body weight. The activities of key enzymes of carbohydrate metabolism such as phosphoenolpyruvate carboxykinase, fructose-1,6-bisphosphatase and glucose-6-phosphatase were significantly (p<0.05) increased and the activities of hexokinase and glucose-6-phosphate dehydrogenase were significantly (p<0.05) decreased in the liver and kidney of diabetic control rats. Further, antioxidants were lowered in diabetic control rats. A significant (p<0.05) decline in glycogen level in the liver and muscle and glycogen synthase activity in the liver and a significant (p<0.05) increase in the activity of liver glycogen phosphorylase were observed in diabetic control rats compared to normal control rats. Oral administration of tyrosol to diabetic rats reversed all the above mentioned biochemical parameters to near normal in a dose dependent manner. Tyrosol at a dose of 20mg/kg body weight showed the highest significant effect than the other two doses. Immunohistochemical staining of pancreas revealed that tyrosol treated diabetic rats showed increased insulin immunoreactive β-cells, which confirmed the biochemical findings. The observed results were compared with glibenclamide, a standard oral hypoglycemic drug. The results of the present study suggest

  20. Effect of aging on brain respiration and carbohydrate metabolism of Syrian hamsters.

    PubMed

    Fox, J H; Parmacek, M S; Patel-Mandlik, K

    1975-01-01

    Syrian hamsters were used to study the effect of aging on brain slice respiration and metabolism. Young animals (average age 8 months) and old animals (average age 18 months) were incubated under standard conditions with the following parameters being measured: oxygen uptake, 14CO2 production, glucose utilization, lactate and pyruvate formation. No differences were found in the two groups. It is still very likely that subtle differences exist but can only be documented under conditions of metabolic stress.

  1. Carbohydrate oxidation coupled to Fe(III) reduction, a novel form of anaerobic metabolism

    USGS Publications Warehouse

    Coates, J.D.; Councell, T.; Ellis, D.J.; Lovley, D.R.

    1998-01-01

    An isolate, designated GC-29, that could incompletely oxidize glucose to acetate and carbon dioxide with Fe(III) serving as the electron acceptor was recovered from freshwater sediments of the Potomac River, Maryland. This metabolism yielded energy to support cell growth. Strain GC-29 is a facultatively anaerobic, Gram-negative motile rod which, in addition to glucose, also used sucrose, lactate, pyruvate, yeast extract, casamino acids or H2 as alternative electron donors for Fe(III) reduction. Stain GC-29 could reduce NO-3, Mn(IV), U(VI), fumarate, malate, S2O32-, and colloidal S0 as well as the humics analog, 2,6-anthraquinone disulfonate. Analysis of the almost complete 16S rRNA sequence indicated that strain GC-29 belongs in the Shewanella genus in the epsilon subdivision of the Proteobacteria. The name Shewanella saccharophilia is proposed. Shewanella saccharophilia differs from previously described fermentative microorganisms that metabolize glucose with the reduction of Fe(III) because it transfers significantly more electron equivalents to Fe(III); acetate and carbon dioxide are the only products of glucose metabolism; energy is conserved from Fe(III) reduction; and glucose is not metabolized in the absence of Fe(III). The metabolism of organisms like S. saccharophilia may account for the fact that glucose is metabolized primarily to acetate and carbon dioxide in a variety of sediments in which Fe(III) reduction is the terminal electron accepting process.

  2. A low carbohydrate diet affects autonomic modulation during heavy but not moderate exercise.

    PubMed

    Lima-Silva, Adriano Eduardo; Bertuzzi, Rômulo C M; Pires, Flávio O; Fronchetti, Lenise; Gevaerd, Monique S; De-Oliveira, Fernando R

    2010-04-01

    The aim of this study was to examine the effects of low carbohydrate (CHO) availability on heart rate variability (HRV) responses during moderate and severe exercise intensities until exhaustion. Six healthy males (age, 26.5 +/- 6.7 years; body mass, 78.4 +/- 7.7 kg; body fat %, 11.3 +/- 4.5%; V(O)(2)(max) 39.5 +/- 6.6 mL kg(-1) min(-1)) volunteered for this study. All tests were performed in the morning, after 8-12 h overnight fasting, at a moderate intensity corresponding to 50% of the difference between the first (LT(1)) and second (LT(2)) lactate breakpoints and at a severe intensity corresponding to 25% of the difference between the maximal power output and LT(2). Forty-eight hours before each experimental session, the subjects performed a 90-min cycling exercise followed by 5-min rest periods and subsequent 1-min cycling bouts at 125% V(O)(2)(max) (with 1-min rest periods) until exhaustion, in order to deplete muscle glycogen. A diet providing 10% (CHO(low)) or 65% (CHO(control)) of energy as carbohydrates was consumed for the following 2 days until the experimental test. The Poicaré plots (standard deviations 1 and 2: SD1 and SD2, respectively) and spectral autoregressive model (low frequency LF, and high frequency HF) were applied to obtain HRV parameters. The CHO availability had no effect on the HRV parameters or ventilation during moderate-intensity exercise. However, the SD1 and SD2 parameters were significantly higher in CHO(low) than in CHO(control), as taken at exhaustion during the severe-intensity exercise (P < 0.05). The HF and LF frequencies (ms(2)) were also significantly higher in CHO(low) than in CHO(control) (P < 0.05). In addition, ventilation measured at the 5 and 10-min was higher in CHO(low) (62.5 +/- 4.4 and 74.8 +/- 6.5 L min(-1), respectively, P < 0.05) than in CHO(control) (70.0 +/- 3.6 and 79.6 +/- 5.1 L min(-1), respectively; P < 0.05) during the severe-intensity exercise. These results suggest that the CHO availability alters the

  3. The correlations of glycated hemoglobin and carbohydrate metabolism parameters with heart rate variability in apparently healthy sedentary young male subjects

    PubMed Central

    Cherkas, Andriy; Abrahamovych, Orest; Golota, Sergii; Nersesyan, Armen; Pichler, Christoph; Serhiyenko, Victoria; Knasmüller, Siegfried; Zarkovic, Neven; Eckl, Peter

    2015-01-01

    Introduction Sedentary lifestyle is a major risk factor for diabetes, cardiovascular and many other age-related diseases. Heart rate variability (HRV) reflects the function of regulatory systems of internal organs and may sensitively indicate early metabolic disturbances. We hypothesize that quantitative and qualitative changes of HRV in young subjects may reflect early metabolic derangements responsible for further development of clinically significant disease. Aim The aim of our study was to determine whether the parameters of carbohydrate metabolism (fasting blood glucose, HBA1c and surrogate insulin sensitivity/resistance indices) correlate with anthropometric data and HRV. Methods The study group consisted of 30 healthy sedentary male subjects aged 20–40, nonsmokers, mainly office and research employees, medical staff and students. Athletes, actively training more than one hour per week, severely obese and men of physical work were excluded from the study. HRV parameters were derived from short term ECG records (five minutes intervals) in supine position and during orthostatic test. Anthropometric data included height, weight, body mass index (BMI), age and body composition (estimation by bioelectric impedance method). The fasting blood glucose, insulin and C-peptide, homeostatic model assessment (HOMA-IR) index and glycated hemoglobin (HbA1c) were evaluated. Linear correlation coefficient (r) was calculated using Statistica 10.0 software. Results and discussion HOMA-IR index correlated positively with body weight, visceral fat and BMI (p=0.047, 0.027 and 0.017 respectively). In supine position pNN50 positively correlated with glucose/insulin ratio (p=0.011) and heart rate with HOMA-IR (p=0.006). In orthostatic test negative correlations of HBA1c with standard deviation, total and low frequency power were determined (p=0.034, 0.400 and 0.403 respectively), which indicates a gradual worsening of functional capacity of cardiovascular system with low

  4. [Effect of vibration, noise, physical exertion and unfavorable microclimate on carbohydrate metabolism in workers engaged into mining industry and machine building].

    PubMed

    Lapko, I V; Kir'iakov, V A; Antoshina, L I; Pavlovskaia, N A; Kondratovich, S V

    2014-01-01

    The authors studied influence of vibration, noise, physical overexertion and microclimate on carbohydrates metabolism and insulin resistance in metal mining industry workers. Findings are that vibration disease appeared to have maximal effect on insulin resistance test results and insulin level. The authors suggested biomarkers for early diagnosis of insulin resistance disorders in metal mining industry workers.

  5. Enhancing the Sweetness of Yoghurt through Metabolic Remodeling of Carbohydrate Metabolism in Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus

    PubMed Central

    Sørensen, Kim I.; Curic-Bawden, Mirjana; Junge, Mette P.; Janzen, Thomas

    2016-01-01

    ABSTRACT Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus are used in the fermentation of milk to produce yoghurt. These species normally metabolize only the glucose moiety of lactose, secreting galactose and producing lactic acid as the main metabolic end product. We used multiple serial selection steps to isolate spontaneous mutants of industrial strains of S. thermophilus and L. delbrueckii subsp. bulgaricus that secreted glucose rather than galactose when utilizing lactose as a carbon source. Sequencing revealed that the S. thermophilus strains had mutations in the galKTEM promoter, the glucokinase gene, and genes encoding elements of the glucose/mannose phosphotransferase system (PTS). These strains metabolize galactose but are unable to phosphorylate glucose internally or via the PTS. The L. delbrueckii subsp. bulgaricus mutants had mutations in genes of the glucose/mannose PTS and in the pyruvate kinase gene. These strains cannot grow on exogenous glucose but are proficient at metabolizing internal glucose released from lactose by β-galactosidase. The resulting strains can be combined to ferment milk, producing yoghurt with no detectable lactose, moderate levels of galactose, and high levels of glucose. Since glucose tastes considerably sweeter than either lactose or galactose, the sweetness of the yoghurt is perceptibly enhanced. These strains were produced without the use of recombinant DNA technology and can be used for the industrial production of yoghurt with enhanced intrinsic sweetness and low residual levels of lactose. IMPORTANCE Based on a good understanding of the physiology of the lactic acid bacteria Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, we were able, by selecting spontaneously occurring mutants, to change dramatically the metabolic products secreted into the growth medium. These mutants consume substantially more of the lactose, metabolize some of the galactose, and secrete the

  6. Metabolic Disorders

    MedlinePlus

    ... affect the breakdown of amino acids, carbohydrates, or lipids. Another group, mitochondrial diseases, affects the parts of the cells that produce the energy. You can develop a metabolic disorder when some organs, such as your liver or pancreas, become diseased or do not function ...

  7. Characterizing the Network of Drugs and Their Affected Metabolic Subpathways

    PubMed Central

    Li, Jing; Han, Junwei; Wang, Shuyuan; Yao, Qianlan; Wang, Yingying; Zhang, Yunpeng; Zhang, Chunlong; Xu, Yanjun; Jiang, Wei; Li, Xia

    2012-01-01

    A fundamental issue in biology and medicine is illustration of the overall drug impact which is always the consequence of changes in local regions of metabolic pathways (subpathways). To gain insights into the global relationship between drugs and their affected metabolic subpathways, we constructed a drug–metabolic subpathway network (DRSN). This network included 3925 significant drug–metabolic subpathway associations representing drug dual effects. Through analyses based on network biology, we found that if drugs were linked to the same subpathways in the DRSN, they tended to share the same indications and side effects. Furthermore, if drugs shared more subpathways, they tended to share more side effects. We then calculated the association score by integrating drug-affected subpathways and disease-related subpathways to quantify the extent of the associations between each drug class and disease class. The results showed some close drug–disease associations such as sex hormone drugs and cancer suggesting drug dual effects. Surprisingly, most drugs displayed close associations with their side effects rather than their indications. To further investigate the mechanism of drug dual effects, we classified all the subpathways in the DRSN into therapeutic and non-therapeutic subpathways representing drug therapeutic effects and side effects. Compared to drug side effects, the therapeutic effects tended to work through tissue-specific genes and these genes tend to be expressed in the adrenal gland, liver and kidney; while drug side effects always occurred in the liver, bone marrow and trachea. Taken together, the DRSN could provide great insights into understanding the global relationship between drugs and metabolic subpathways. PMID:23112813

  8. Effect of the Ratio of Non-fibrous Carbohydrates to Neutral Detergent Fiber and Protein Structure on Intake, Digestibility, Rumen Fermentation, and Nitrogen Metabolism in Lambs.

    PubMed

    Ma, T; Tu, Y; Zhang, N F; Deng, K D; Diao, Q Y

    2015-10-01

    This study aimed to investigate the effect of the ratio of non-fibrous carbohydrates to neutral detergent fibre (NFC/NDF) and undegraded dietary protein (UDP) on rumen fermentation and nitrogen metabolism in lambs. Four Dorper×thin-tailed Han crossbred lambs, averaging 62.3±1.9 kg of body weight and 10 mo of age, were randomly assigned to four dietary treatments of combinations of two levels of NFC/NDF (1.0 and 1.7) and two levels of UDP (35% and 50% of crude protein [CP]). Duodenal nutrient flows were measured with dual markers of Yb and Co, and microbial N (MN) synthesis was estimated using (15)N. High UDP decreased organic matter (OM) intake (p = 0.002) and CP intake (p = 0.005). Ruminal pH (p<0.001), ammonia nitrogen (NH3-N; p = 0.008), and total volatile fatty acids (p<0.001) were affected by dietary NFC/NDF. The ruminal concentration of NH3-N was also affected by UDP (p<0.001). The duodenal flow of total MN (p = 0.007) was greater for lambs fed the high NFC/NDF diet. The amount of metabolisable N increased with increasing dietary NFC:NDF (p = 0.02) or UDP (p = 0.04). In conclusion, the diets with high NFC/NDF (1.7) and UDP (50% of CP) improved metabolisable N supply to lambs.

  9. The Effects of Space Flight on Some Liver Enzymes Concerned with Carbohydrate and Lipid Metabolism in Rats

    NASA Technical Reports Server (NTRS)

    Abraham, S.; Lin, C. Y.; Klein, H. P.; Volkmann, C.

    1978-01-01

    The activities of about 30 enzymes concerned with carbohydrate and lipid metabolism and the levels of glycogen and of individual fatty acids were measured in livers of rats ex- posed to prolonged space flight (18.5 days) aboard COSMOS 986 Biosatellite. When flight stationary, (FS) and flight centrifuged (FC) rats were compared at recovery (R(sub 0)), decrceases in the activities of glycogen phosphorylase, alpha glycerphosphate, acyl transferase, diglyceride acyl transferase, acconitase and Epsilon-phosphogluconate dehydrogenase were noted in the weightless group (FS). The significance of these findings was strengthened since all activities, showing alterations at R(sub 0), returned to normal 25 days post-flight. Differences were also seen in levels of two liver constituents. When glycogen and total fatty acids of the two groups of flight animals were determined, differences that could be attributed to reduced gravity were observed, the FS group at R(sub 0) contained, on the average, more than twice the amount of glycogen than did controls ad a remarkable shift in the ratio of palmitate to palmitoleate were noted. These metabolic alterations appear to be unique to the weightless condition. Our data justify the conclusion that centrifugation during space flight is equivalent to terrestrial gravity.

  10. Correlation of serum ghrelin levels with body mass index and carbohydrate metabolism in patients treated with atypical antipsychotics.

    PubMed

    Palik, E; Birkás, K D; Faludi, G; Karádi, I; Cseh, K

    2005-06-01

    The prevalence of diabetes mellitus and metabolic syndrome is higher in patients with schizophrenia than in the normal population. Atypical antipsychotic drugs are used in psychiatry since the beginning of 1990. These drugs differ from the "typical" antipsychotics used previously, as they have less extrapyramidal side effects, and because of this they are tolerated better, but are associated with weight-gain and disturbances in carbohydrate metabolism. Ghrelin is an orexigen hormone partaking in body weight regulation. It is produced in the enteroendocrine P/D1 cells of the gastric mucosa and secreted to the circulation. The aim of our study was to determine ghrelin levels of atypical antipsychotic-treated patients in relationship with their body mass index (BMI) and carbohydrate metabolism. We measured the fasting serum ghrelin levels in 56 patients (male/female: 16/40, age mean+/-S.D.: 50.6+/-5.6 years) treated with atypical antipsychotics (clozapine, olanzapine, risperidon and quetiapine), and in 75 healthy control subjects, age and gender matched (RIA Linco, USA) in relationship with their BMI and their fasting and 75 g OGTT 120 min blood glucose values. The serum ghrelin levels of the patient group were notably higher (1333+/-659 pg/ml) than in the control group (368+/-103, p<0.0001; Mann-Whitney). We found no difference among the four antipsychotics in weight-gain, diabetes prevalence and the serum ghrelin levels. The BMI of the patient group was significantly higher (29.3+/-7.2 kg/m2 versus 24.3+/-3.7 kg/m2, p<0.0001; Mann-Whitney); 32% of them had blood glucose abnormality (18/56). There was no difference between the ghrelin levels in diabetic and non-diabetic patients. We found a significant negative linear correlation between the serum ghrelin and BMI (r=-0.35, p=0.0078; Spearman), the ghrelin and fasting blood glucose (r=-0.32, p=0.015) and OGTT 75 g 120 min blood glucose levels (r=-0.27, p=0.036). The orexigen effect of elevated serum ghrelin levels can

  11. Effects of heat stress on carbohydrate and lipid metabolism in growing pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heat stress (HS) jeopardizes human and animal health and reduces animal agriculture productivity; however, its pathophysiology is not well understood. Study objectives were to evaluate the effects of HS on basal and stimulated energetic metabolism. Crossbred female pigs (57±5 kg body weight) were ...

  12. The Metabolic Effects of Low-Carbohydrate Diets and Incorporation into a Biochemistry Course

    ERIC Educational Resources Information Center

    Pogozelski, Wendy; Arpaia, Nicholas; Priore, Salvatore

    2005-01-01

    One of the challenges in teaching biochemistry is facilitating students' interest in and mastery of metabolism. The many pathways and modes of regulation can be overwhelming for students to learn and difficult for professors to teach in an engaging manner. We have found it useful to take advantage of prevailing interest in popular yet…

  13. Teaching Arrangements of Carbohydrate Metabolism in Biochemistry Curriculum in Peking University Health Science Center

    ERIC Educational Resources Information Center

    Chen, Hao; Ni, Ju-Hua

    2013-01-01

    Biochemistry occupies a unique place in the medical school curricula, but the teaching of biochemistry presents certain challenges. One of these challenges is facilitating students' interest in and mastery of metabolism. The many pathways and modes of regulation can be overwhelming for students to learn and difficult for professors to teach in an…

  14. Does gibberellin biosynthesis play a critical role in the growth of Lolium perenne? Evidence from a transcriptional analysis of gibberellin and carbohydrate metabolic genes after defoliation

    PubMed Central

    Liu, Qianhe; Jones, Chris S.; Parsons, Anthony J.; Xue, Hong; Rasmussen, Susanne

    2015-01-01

    Global meat and milk production depends to a large extent on grazed pastures, with Lolium perenne being the major forage grass in temperate regions. Defoliation and subsequent regrowth of leaf blades is a major and essential event with respect to L. perenne growth and productivity. Following defoliation, carbohydrates (mainly fructans and sucrose) have to be mobilized from heterotrophic tissues to provide energy and carbon for regrowth of photosynthetic tissues. This mobilization of reserve carbohydrates requires a substantial change in the expression of genes coding for enzymes involved in carbohydrate metabolism. Here we tested the hypothesis that gibberellins (GA) are at the core of the processes regulating the expression of these genes. Thus, we examined the transcript profiles of genes involved in carbohydrate and GA metabolic pathways across a time course regrowth experiment. Our results show that following defoliation, the immediate reduction of carbohydrate concentrations in growing tissues is associated with a concomitant increase in the expression of genes encoding carbohydrate mobilizing invertases, and was also associated with a strong decrease in the expression of fructan synthesizing fructosyltransferase genes. We also show that the decrease in fructan levels is preceded by increased expression of the GA activating gene GA3-oxidase and decreased expression of the GA inactivating gene GA2-oxidase in sheaths. GA3-oxidase expression was negatively, while GA2-oxidase positively linked to sucrose concentrations. This study provides indicative evidence that gibberellins might play a role in L. perenne regrowth following defoliation and we hypothesize that there is a link between gibberellin regulation and sugar metabolism in L. perenne. PMID:26579182

  15. Food odors trigger an endocrine response that affects food ingestion and metabolism.

    PubMed

    Lushchak, Oleh V; Carlsson, Mikael A; Nässel, Dick R

    2015-08-01

    Food odors stimulate appetite and innate food-seeking behavior in hungry animals. The smell of food also induces salivation and release of gastric acid and insulin. Conversely, sustained odor exposure may induce satiation. We demonstrate novel effects of food odors on food ingestion, metabolism and endocrine signaling in Drosophila melanogaster. Acute exposure to attractive vinegar odor triggers a rapid and transient increase in circulating glucose, and a rapid upregulation of genes encoding the glucagon-like hormone adipokinetic hormone (AKH), four insulin-like peptides (DILPs) and some target genes in peripheral tissues. Sustained exposure to food odors, however, decreases food intake. Hunger-induced strengthening of synaptic signaling from olfactory sensory neurons (OSNs) to brain neurons increases food-seeking behavior, and conversely fed flies display reduced food odor sensitivity and feeding. We show that increasing the strength of OSN signaling chronically by genetic manipulation of local peptide neuromodulation reduces feeding, elevates carbohydrates and diminishes lipids. Furthermore, constitutively strengthened odor sensitivity altered gene transcripts for AKH, DILPs and some of their targets. Thus, we show that food odor can induce a transient anticipatory endocrine response, and that boosted sensitivity to this odor affects food intake, as well as metabolism and hormonal signaling.

  16. Evaluation of carbohydrate metabolism inhibition by some species of medicinal mushrooms from India.

    PubMed

    Kaur, Amandip; Dhingra, G S; Shri, Richa

    2015-01-01

    Diabetes mellitus is one of the most common endocrine diseases. One antidiabetic therapeutic approach is to reduce gastrointestinal glucose production and absorption through the inhibition of α-amylase and α-amyloglucosidase enzymes, thereby preventing an increase in the postprandial glucose concentration in diabetics. The main aim of this study was to evaluate the antidiabetic potential of hydroalcoholic extracts of 3 mushrooms, that is, Ganoderma philippii, Lenzites elegans, and Rigidoporus ulmarius, using an in vitro enzymatic starch digestion assay model. The α-amylase and α-glucosidase inhibitory potential of hydroalcoholic mushroom extracts was tested at concentrations of 1, 5, 10, 12.5, 25, 50, and 100 mg/mL. Acarbose was used as a control. The amount of glucose liberated (micrograms) was determined using the 3,5-dinitrosalicylic acid method. Phytochemical screening revealed the presence of carbohydrates in all examined species. In the case of G. philippii and L. elegans, a concentration-dependent increase in the percentage inhibition of enzyme activity was observed, with maximum inhibition at a concentration of 100 mg/mL (40.22% ± 0.83% and 26.57% ± 0.68%, respectively). R. ulmarius showed maximum inhibitory activity at a concentration of 100 mg/mL (65.54% ± 0.91%), and this was comparable to acarbose.

  17. Protective effects of vescalagin from pink wax apple [Syzygium samarangense (Blume) Merrill and Perry] fruit against methylglyoxal-induced inflammation and carbohydrate metabolic disorder in rats.

    PubMed

    Chang, Wen-Chang; Shen, Szu-Chuan; Wu, James Swi-Bea

    2013-07-24

    The unbalance of glucose metabolism in humans may cause the excessive formation of methylglyoxal (MG), which can react with various biomolecules to form the precursor of advanced glycation end products (AGEs). Vescalagin (VES) is an ellagitannin that alleviates insulin resistance in cell study. Results showed that VES reduced the value of oral glucose tolerance test, cardiovascular risk index, AGEs, and tumor necrosis factor-α contents while increasing C-peptide and d-lactate contents significantly in rats orally administered MG and VES together. The preventive effect of VES on MG-induced inflammation and carbohydrate metabolic disorder in rats was thus proved. On the basis of the experiment data, a mechanism, which involves the increase in d-lactate to retard AGE formation and the decrease in cytokine release to prevent β-cell damage, is proposed to explain the bioactivities of VES in antiglycation and in the alleviation of MG-induced carbohydrate metabolic disorder in rats.

  18. Alteration of carbohydrates metabolism and midgut glucose absorption in Gromphadorhina portentosa after subchronic exposure to imidacloprid and fenitrothion.

    PubMed

    Sawczyn, Tomasz; Dolezych, Bogdan; Klosok, Marcin; Augustyniak, Maria; Stygar, Dominika; Buldak, Rafal J; Kukla, Michal; Michalczyk, Katarzyna; Karcz-Socha, Iwona; Zwirska-Korczala, Krystyna

    2012-01-01

    This study was undertaken to test the hypothesis that following exposure to insecticides, changes take place in the metabolism of carbohydrates and absorption in the midgut of insects. The Madagascar hissing cockroach (Gromphadorhina portentosa) was chosen for the experiment as a model organism, due to it being easy to breed and its relatively large alimentary tract, which was important when preparing the microperfusion midgut bioassay. In each group of cockroaches treated with imidacloprid and fenitrothion, absorption of glucose, expressed as the area under the curve (AUC), was elevated compared to the control group. Glucose in the hemolymph of the examined insects was present in a vestigial amount, often below the threshold of determination, so the determinable carbohydrate indices were: hemolymph trehalose concentration and fat body glycogen content. The level of trehalose found in the hemolymph of insects when exposed to fenitrothion, and irrespective of the level of concentration mixed into food, were significantly lower when comparing to the control samples. Imidacloprid acted analogically with one exception at the concentration of 10 mg·kg(-1) dry food where trehalose concentration did not differ from the control values. Coupling with fat body glycogen concentration was less visible and appeared only at the concentrations of 5 and 10 mg imidacloprid·kg(-1) dry food. As described in this study changes in the sugar distribution and midgut glucose absorption indicate that insects cover the increased energy needs induced by insecticides; also at the gastrointestinal tract level. The result indicates that the midgut glucose absorption parameters could be considered as a non-specific biomarker of insecticide toxicity.

  19. Hematological and metabolic responses to training in racing sled dogs fed diets containing medium, low, or zero carbohydrate.

    PubMed

    Kronfeld, D S; Hammel, E P; Ramberg, C F; Dunlap, H L

    1977-03-01

    In a 28 week study, 18 racing sled dogs were trained to maximal fitness in 12 weeks, sustained through a racing season of 12 weeks, followed by gradual of training of 4 weeks. The dogs were fed a predominantly cereal diet prior to the study; experimental diets containing more chicken and meat by products were introduced from the 2nd to the 4th week of training. On an energy basis, the diets contained protein, fat, and carbohydrate in the proportions of 39:61:0 (diet A), 32:45:23 (diet B), and 28:34:38 (diet C). Blood samples were taken at rest just before the start of training, at 6, 12,24 and 28 weeks; 33 variables were measured on most samples. The results were subjected to analysis of variance. No adverse effects were observed in dogs fed the extreme diet A. Significant relationships to training were shown by serum glutamic oxaloacetic transaminase, creatinine, packed cell volume, calcium, hemoglobin, and globulin. Serum cholesterol concentration increased with the introduction of the higher protein-fat diets; the high concentrations attenuated with time but rose again when training was abated. Dogs on diet A maintained higher serum concentrations of albumin, calcium, magnesium, and free fatty acids during the racing season than did dogs fed diets B or C. They also exhibited the greatest increases in red cell count, hemoglobin concentration, and packed cell volume during training. High values of red cell indices were not sustained through the racing season in dogs fed diet C. In addition to attributes already widely appreciated, viz. a higher energy density an digestibility, the carbohydrate-free, high-fat diet A appeared to confer advantages for prolonged strenuous running in terms of certain metabolic responses to training.

  20. Transcript profiling of Paoenia ostii during artificial chilling induced dormancy release identifies activation of GA pathway and carbohydrate metabolism.

    PubMed

    Gai, Shupeng; Zhang, Yuxi; Liu, Chunying; Zhang, Yang; Zheng, Guosheng

    2013-01-01

    Endo-dormant flower buds must pass through a period of chilling to reinitiate growth and subsequent flowering, which is a major obstacle to the forcing culture of tree peony in winter. Customized cDNA microarray (8×15 K element) was used to investigate gene expression profiling in tree peony 'Feng Dan Bai' buds during 24 d chilling treatment at 0-4°C. According to the morphological changes after the whole plants were transferred to green house, endo-dormancy was released after 18 d chilling treatment, and prolonged chilling treatment increased bud break rate. Pearson correlation hierarchical clustering of sample groups was highly consistent with the dormancy transitions revealed by morphological changes. Totally 3,174 significantly differentially-expressed genes (P<0.05) were observed through endo-dormancy release process, of which the number of up-regulated (1,611) and that of down-regulated (1,563) was almost the same. Functional annotation of differentially-expressed genes revealed that cellular process, metabolic process, response to stimulus, regulation of biological process and development process were well-represented. Hierarchical clustering indicated that activation of genes involved in carbohydrate metabolism (Glycolysis, Citrate cycle and Pentose phosphate pathway), energy metabolism and cell growth. Based on the results of GO analysis, totally 51 probes presented in the microarray were associated with GA response and GA signaling pathway, and 22 of them were differently expressed. The expression profiles also revealed that the genes of GA biosynthesis, signaling and response involved in endo-dormancy release. We hypothesized that activation of GA pathway played a central role in the regulation of dormancy release in tree peony.

  1. Regulation of Genes Controlling Carbohydrate Metabolism in the Heart of a Hibernating Mammal

    DTIC Science & Technology

    2006-05-31

    concludes in mid-March. PTL is expressed in addition to hormone-sensitive lipase, the enzyme typically responsible for hydrolysis of triacylglycerols...same enzyme found in humans. 4 Figure 1. Model showing the metabolic involvement of pyruvate dehydrogenase kinase isozyme 4 (PDK- 4) and pancreatic...Gluconeogenesis TG HEART glucose ffa TG glycerol ffa acetyl-CoA TCA Cycle Oxidationβ- net 2 ATP Triglyceride Synthesis G-3-P ATP + CO2 + H2O PDK-4 PTL lactate

  2. Structure and Function of Human Xylulokinase, an Enzyme with Important Roles in Carbohydrate Metabolism*

    PubMed Central

    Bunker, Richard D.; Bulloch, Esther M. M.; Dickson, James M. J.; Loomes, Kerry M.; Baker, Edward N.

    2013-01-01

    d-Xylulokinase (XK; EC 2.7.1.17) catalyzes the ATP-dependent phosphorylation of d-xylulose (Xu) to produce xylulose 5-phosphate (Xu5P). In mammals, XK is the last enzyme in the glucuronate-xylulose pathway, active in the liver and kidneys, and is linked through its product Xu5P to the pentose-phosphate pathway. XK may play an important role in metabolic disease, given that Xu5P is a key regulator of glucose metabolism and lipogenesis. We have expressed the product of a putative human XK gene and identified it as the authentic human d-xylulokinase (hXK). NMR studies with a variety of sugars showed that hXK acts only on d-xylulose, and a coupled photometric assay established its key kinetic parameters as Km(Xu) = 24 ± 3 μm and kcat = 35 ± 5 s−1. Crystal structures were determined for hXK, on its own and in complexes with Xu, ADP, and a fluorinated inhibitor. These reveal that hXK has a two-domain fold characteristic of the sugar kinase/hsp70/actin superfamily, with glycerol kinase as its closest relative. Xu binds to domain-I and ADP to domain-II, but in this open form of hXK they are 10 Å apart, implying that a large scale conformational change is required for catalysis. Xu binds in its linear keto-form, sandwiched between a Trp side chain and polar side chains that provide exquisite hydrogen bonding recognition. The hXK structure provides a basis for the design of specific inhibitors with which to probe its roles in sugar metabolism and metabolic disease. PMID:23179721

  3. Effect of hyperbaric oxygenation on carbohydrate metabolism protein synthesis in the myocardium during sustained hypodynamia

    NASA Technical Reports Server (NTRS)

    Makarov, G. A.

    1980-01-01

    Glycolysis and the intensity of protein synthesis were studied in 140 white male rats in subcellular fractions of the myocardium during 45 day hypodynamia and hyperbaric oxygenation. Hypodynamia increased: (1) the amount of lactic acids; (2) the amount of pyruvic acid; (3) the lactate/pyruvate coefficient; and (4) the activities of aldolase and lactate dehydrogenase. Hyperbaric oxygenation was found to have a favorable metabolic effect on the animals with hypodynamia.

  4. Metabolic and carbohydrate characteristics of different phenotypes of polycystic ovary syndrome

    PubMed Central

    Çelik, Ebru; Türkçüoğlu, Ilgın; Ata, Barış; Karaer, Abdullah; Kırıcı, Pınar; Eraslan, Sevil; Taşkapan, Çağatay; Berker, Bülent

    2016-01-01

    Objective To compare the prevalence of various metabolic and cardiovascular risk factors and insulin resistance between polycystic ovary syndrome (PCOS) patients with or without hyperandrogenism. Material and Methods This is a retrospective cross-sectional study involving women with PCOS as diagnosed according to the Androgen Excess (AE) Society definition (n=504) and women with normoandrogenemic PCOS (n=183). Anthropometrics, lipid profile, glucose, insulin, oral glucose tolerance test (OGTT), and reproductive hormone levels were evaluated. Results Women with PCOS diagnosed according to the AE Society had a significantly higher prevalence of metabolic syndrome compared with the normoandrogenemic PCOS phenotype: odds ratio (OR) 2.95 [95% confidence interval (CI) 1.21–7.21]. There was no significant difference in the prevalence glucose intolerance test between the groups [OR: 2.15, 95% CI 0.71–6.56]. The prevalence of low high density lipoprotein (HDL)-cholesterol in the group under the AE-PCOS Society criteria was higher than that of the normoandrogenemic PCOS group [OR: 2.82, 95%CI 1.29–3.36]. Conclusion The risks of metabolic syndrome and cardiovascular disease may vary among the phenotypes of PCOS based on the Rotterdam criteria. This new data may be of reference in informing women with PCOS, although further prospective studies are needed to validate this proposition. PMID:27990089

  5. Fermentation and Hydrogen Metabolism Affect Uranium Reduction by Clostridia

    SciTech Connect

    Gao, Weimin; Francis, Arokiasamy J.

    2013-01-01

    Previously, it has been shown that not only is uranium reduction under fermentation condition common among clostridia species, but also the strains differed in the extent of their capability and the pH of the culture significantly affected uranium(VI) reduction. In this study, using HPLC and GC techniques, metabolic properties of those clostridial strains active in uranium reduction under fermentation conditions have been characterized and their effects on capability variance of uranium reduction discussed. Then, the relationship between hydrogen metabolism and uranium reduction has been further explored and the important role played by hydrogenase in uranium(VI) and iron(III) reduction by clostridia demonstrated. When hydrogen was provided as the headspace gas, uranium(VI) reduction occurred in the presence of whole cells of clostridia. This is in contrast to that of nitrogen as the headspace gas. Without clostridia cells, hydrogen alone could not result in uranium(VI) reduction. In alignment with this observation, it was also found that either copper(II) addition or iron depletion in the medium could compromise uranium reduction by clostridia. In the end, a comprehensive model was proposed to explain uranium reduction by clostridia and its relationship to the overall metabolism especially hydrogen (H2) production.

  6. Fermentation and Hydrogen Metabolism Affect Uranium Reduction by Clostridia

    PubMed Central

    Gao, Weimin; Francis, Arokiasamy J.

    2013-01-01

    Previously, it has been shown that not only is uranium reduction under fermentation condition common among clostridia species, but also the strains differed in the extent of their capability and the pH of the culture significantly affected uranium(VI) reduction. In this study, using HPLC and GC techniques, metabolic properties of those clostridial strains active in uranium reduction under fermentation conditions have been characterized and their effects on capability variance of uranium reduction discussed. Then, the relationship between hydrogen metabolism and uranium reduction has been further explored and the important role played by hydrogenase in uranium(VI) and iron(III) reduction by clostridia demonstrated. When hydrogen was provided as the headspace gas, uranium(VI) reduction occurred in the presence of whole cells of clostridia. This is in contrast to that of nitrogen as the headspace gas. Without clostridia cells, hydrogen alone could not result in uranium(VI) reduction. In alignment with this observation, it was also found that either copper(II) addition or iron depletion in the medium could compromise uranium reduction by clostridia. In the end, a comprehensive model was proposed to explain uranium reduction by clostridia and its relationship to the overall metabolism especially hydrogen (H2) production. PMID:25937978

  7. Fermentation and Hydrogen Metabolism Affect Uranium Reduction by Clostridia

    DOE PAGES

    Gao, Weimin; Francis, Arokiasamy J.

    2013-01-01

    Previously, it has been shown that not only is uranium reduction under fermentation condition common among clostridia species, but also the strains differed in the extent of their capability and the pH of the culture significantly affected uranium(VI) reduction. In this study, using HPLC and GC techniques, metabolic properties of those clostridial strains active in uranium reduction under fermentation conditions have been characterized and their effects on capability variance of uranium reduction discussed. Then, the relationship between hydrogen metabolism and uranium reduction has been further explored and the important role played by hydrogenase in uranium(VI) and iron(III) reduction bymore » clostridia demonstrated. When hydrogen was provided as the headspace gas, uranium(VI) reduction occurred in the presence of whole cells of clostridia. This is in contrast to that of nitrogen as the headspace gas. Without clostridia cells, hydrogen alone could not result in uranium(VI) reduction. In alignment with this observation, it was also found that either copper(II) addition or iron depletion in the medium could compromise uranium reduction by clostridia. In the end, a comprehensive model was proposed to explain uranium reduction by clostridia and its relationship to the overall metabolism especially hydrogen (H 2 ) production.« less

  8. Influence of low-power laser radiation on carbohydrate metabolism and insulin-glycemic balance in experimental animals

    NASA Astrophysics Data System (ADS)

    Radelli, Jolanta; Cieslar, Grzegorz; Sieron, Aleksander; Grzybek, Henryk

    1996-11-01

    The aim of the study was to determine the dose-dependent influence of low-power laser radiation on carbohydrate metabolism in 70 male Wistar rats. The animals were primarily divided into 2 groups: B - irradiated group and C - control one in which sham - irradiation was made. The rats from B - group were irradiated daily for 10 minutes with semiconductive laser emitting the radiation of infrared wavelength 904 nm. Within both groups the animals were divided into subgroups (B I - B VII and CI - C VII) in which the dissections were made on 1st, 3rd, 6th, 9th, and 14th day of irradiation and on 5th and 8th day after the end of cycle of irradiation respectively. In all subgroups blood samples were collected to determine the glucose and insulin levels. Parts of the liver and pancreas were taken for histological examination in light microscope and in electron microscope. The lowest, statistically significant glycaemia was observed in the subgroup B V. Significant increase of glycaemia and significantly higher insulin concentration was found only in the subgroup B VI. The I/G ratio increased significantly in the subgroup B V. Lower intensity of paS reaction was presented in subgroups B I, B III, B V, B VI and B VII. The increased amount of paS-positive substances was observed in the I and II zone of liver acinus. Electron microscopic studies of hepatocytes showed: numerous glycogen conglomerations in subgroups B I, B II, B VI and B VII, the extension of RER in B II and B III, light vacuoles in B II, Golgi apparatus and biliary canaliculus expansion in B V and structural changes of several mitochondria - slight swelling or discontinuation of their outer membranes, electron microscopic findings in pancreas cells included: lower number of typical granules in beta and alpha cells as well as Golgi apparatus results it was concluded that the influence of low power laser radiation on carbohydrate metabolism in generally insignificant. It is observed only for higher doses of

  9. Ecologically Valid Carbohydrate Intake during Soccer-Specific Exercise Does Not Affect Running Performance in a Fed State.

    PubMed

    Funnell, Mark P; Dykes, Nick R; Owen, Elliot J; Mears, Stephen A; Rollo, Ian; James, Lewis J

    2017-01-05

    This study assessed the effect of carbohydrate intake on self-selected soccer-specific running performance. Sixteen male soccer players (age 23 ± 4 years; body mass 76.9 ± 7.2 kg; predicted VO2max = 54.2 ± 2.9 mL∙kg(-1)∙min(-1); soccer experience 13 ± 4 years) completed a progressive multistage fitness test, familiarisation trial and two experimental trials, involving a modified version of the Loughborough Intermittent Shuttle Test (LIST) to simulate a soccer match in a fed state. Subjects completed six 15 min blocks (two halves of 45 min) of intermittent shuttle running, with a 15-min half-time. Blocks 3 and 6, allowed self-selection of running speeds and sprint times, were assessed throughout. Subjects consumed 250 mL of either a 12% carbohydrate solution (CHO) or a non-caloric taste matched placebo (PLA) before and at half-time of the LIST. Sprint times were not different between trials (CHO 2.71 ± 0.15 s, PLA 2.70 ± 0.14 s; p = 0.202). Total distance covered in self-selected blocks (block 3: CHO 2.07 ± 0.06 km; PLA 2.09 ± 0.08 km; block 6: CHO 2.04 ± 0.09 km; PLA 2.06 ± 0.08 km; p = 0.122) was not different between trials. There was no difference between trials for distance covered (p ≥ 0.297) or mean speed (p ≥ 0.172) for jogging or cruising. Blood glucose concentration was greater (p < 0.001) at the end of half-time during the CHO trial. In conclusion, consumption of 250 mL of 12% CHO solution before and at half-time of a simulated soccer match does not affect self-selected running or sprint performance in a fed state.

  10. Sink filling, inulin metabolizing enzymes and carbohydrate status in field grown chicory (Cichorium intybus L.).

    PubMed

    van Arkel, Jeroen; Vergauwen, Rudy; Sévenier, Robert; Hakkert, Johanna C; van Laere, André; Bouwmeester, Harro J; Koops, Andries J; van der Meer, Ingrid M

    2012-10-15

    Inulin is a fructose-based polymer that is isolated from chicory (Cichorium intybus L.) taproots. The degree of polymerization (DP) determines its application and hence the value of the crop. The DP is highly dependent on the field conditions and harvest time. Therefore, the present study was carried out with the objective to understand the regulation of inulin metabolism and the process that determines the chain length and inulin yield throughout the whole growing season. Metabolic aspects of inulin production and degradation in chicory were monitored in the field and under controlled conditions. The following characteristics were determined in taproots: concentrations of glucose, fructose and sucrose, the inulin mean polymer length (mDP), yield, gene expression and activity of enzymes involved in inulin metabolism. Inulin synthesis, catalyzed by sucrose:sucrose 1-fructosyltransferase (EC 2.4.1.99) (1-SST) and fructan:fructan 1-fructosyltransferase (EC 2.4.1.100) (1-FFT), started at the onset of taproot development. Inulin yield as a function of time followed a sigmoid curve reaching a maximum in November. Inulin reached a maximum mDP of about 15 in September, than gradually decreased. Based on the changes observed in the pattern of inulin accumulation, we defined three different phases in the growing season and analyzed product formation, enzyme activity and gene expression in these defined periods. The results were validated by performing experiments under controlled conditions in climate rooms. Our results show that the decrease in 1-SST that starts in June is not regulated by day length and temperature. From mid-September onwards, the mean degree of polymerization (mDP) decreased gradually although inulin yield still increased. The decrease in mDP combined with increased yield results from fructan exohydrolase activity, induced by low temperature, and the back transfer activity of 1-FFT. Overall, this study provides background information on how to improve

  11. Carbohydrate and Amino Acid Metabolism in the Ectomycorrhizal Ascomycete Sphaerosporella brunnea during Glucose Utilization 1

    PubMed Central

    Martin, Francis; Ramstedt, Mauritz; Söderhäll, Kenneth; Canet, Daniel

    1988-01-01

    Nuclear magnetic resonance spectroscopy was utilized to study the metabolism of [1-13C]glucose in mycelia of the ectomycorrhizal ascomycete Sphaerosporella brunnea. The main purpose was to assess the biochemical pathways for the assimilation of glucose and to identify the compounds accumulated during glucose assimilation. The majority of the 13C label was incorporated into mannitol, while glycogen, trehalose and free amino acids were labeled to a much lesser extent. The high enrichment of the C1/C6 position of mannitol indicated that the polyol was formed via a direct route from absorbed glucose. Randomization of the 13C label was observed to occur in glucose and trehalose leading to the accumulation of [1,6-13C]trehalose and [1,6-13C]glucose. This suggests that the majority of the glucose carbon used to form trehalose was cycled through the metabolically active mannitol pool. The proportion of label entering the free amino acids represented 38% of the soluble 13C after 6 hours of continuous glucose labeling. Therefore, amino acid biosynthesis is an important sink of assimilated carbon. Carbon-13 was incorporated into [3-13C]alanine and [2-13C]-, [3-13C]-, and [4-13C]glutamate and glutamine. From the analysis of the intramolecular 13C enrichment of these amino acids, it is concluded that [3-13C]pyruvate, arising from [1-13C]glucose catabolism, was used by alanine aminotransferase, pyruvate dehydrogenase, and pyruvate carboxylase (or phosphoenolpyruvate carboxykinase). Intramolecular 13C labeling patterns of glutamate and glutamine were similar and are consistent with the operation of the Krebs cycle. There is strong evidence for (a) randomization of the label on C2 and C3 positions of oxaloacetate via malate dehydrogenase and fumarase, and (b) the dual biosynthetic and respiratory role of the citrate synthase, aconitase, and isocitrate dehydrogenase reactions. The high flux of carbon through the carboxylation (presumably pyruvate carboxylase) step indicates that CO

  12. Respiration, metabolic balance, and attention in affective picture processing.

    PubMed

    Gomez, Patrick; Shafy, Samiha; Danuser, Brigitta

    2008-05-01

    The respiratory behavior during affective states is not completely understood. We studied breathing pattern responses to picture series in 37 participants. We also measured end-tidal pCO2 (EtCO2) to determine if ventilation is in balance with metabolic demands and spontaneous eye-blinking to investigate the link between respiration and attention. Minute ventilation (MV) and inspiratory drive increased with self-rated arousal. These relationships reflected increases in inspiratory volume rather than shortening of the time parameters. EtCO2 covaried with pleasantness but not arousal. Eye-blink rate decreased with increasing unpleasantness in line with a negativity bias in attention. This study confirms that respiratory responses to affective stimuli are organized to a certain degree along the dimensions of valence and arousal. It shows, for the first time, that during picture viewing, ventilatory increases with increasing arousal are in balance with metabolic activity and that inspiratory volume is modulated by arousal. MV emerges as the most reliable respiratory index of self-perceived arousal.

  13. Interactions between dietary boron and thiamine affect lipid metabolism

    SciTech Connect

    Herbel, J.L.; Hunt, C.D. )

    1991-03-15

    An experiment was designed to test the hypothesis that dietary boron impacts upon the function of various coenzymes involved in energy metabolism. In a 2 {times} 7 factorially-arranged experiment, weanling, vitamin D{sub 3}-deprived rats were fed a ground corn-casein-corn oil based diet supplemented with 0 or 2 mg boron/kg and 50% of the requirement for thiamine (TM), riboflavin (RF), pantothenic acid (PA) or pyridoxine (PX); 0% for folic acid (FA) or nicotinic acid (NA). All vitamins were supplemented in adequate amounts in the control diet. At 8 weeks of age, the TM dietary treatment was the one most affected by supplemental dietary boron (SDB). In rats that were fed 50% TM, SDB increased plasma concentrations of triglyceride (TG) and activity of alanine transaminase (ALT), and the liver to body weight (L/B) ratio. However, in the SDB animals, adequate amounts of TM decreased the means of those variables to near that observed in non-SDB rats fed 50% TM. The findings suggest that an interaction between dietary boron and TM affects lipid metabolism.

  14. Osteoid osteoma is an osteocalcinoma affecting glucose metabolism.

    PubMed

    Confavreux, C B; Borel, O; Lee, F; Vaz, G; Guyard, M; Fadat, C; Carlier, M-C; Chapurlat, R; Karsenty, G

    2012-05-01

    Osteocalcin is a hormone secreted by osteoblasts, which regulates energy metabolism by increasing β-cell proliferation, insulin secretion, insulin sensitivity, and energy expenditure. This has been demonstrated in mice, but to date, the evidence implicating osteocalcin in the regulation of energy metabolism in humans are indirect. To address this question more directly, we asked whether a benign osteoblastic tumor, such as osteoma osteoid in young adults, may secrete osteocalcin. The study was designed to assess the effect of surgical resection of osteoid osteoma on osteocalcin and blood glucose levels in comparison with patients undergoing knee surgery and healthy volunteers. Blood collections were performed the day of surgery and the following morning after overnight fasting. Patients and controls were recruited in the orthopedic surgery department of New York Presbiterian Hospital, NY-USA and Hospices Civils de Lyon, France. Seven young males were included in the study: two had osteoid osteoma, two underwent knee surgery, and three were healthy volunteers. After resection of the osteoid osteomas, we observed a decrease of osteocalcin by 62% and 30% from the initial levels. Simultaneously, blood glucose increased respectively by 32% and 15%. Bone turnover markers were not affected. This case study shows for the first time that osteocalcin in humans affects blood glucose level. This study also suggests that ostoid osteoma may be considered, at least in part, as an osteocalcinoma.

  15. Bole girdling affects metabolic properties and root, trunk and branch hydraulics of young ponderosa pine trees.

    PubMed

    Domec, Jean-Christophe; Pruyn, Michele L

    2008-10-01

    Effects of trunk girdling on seasonal patterns of xylem water status, water transport and woody tissue metabolic properties were investigated in ponderosa pine (Pinus ponderosa Dougl. ex P. Laws.) trees. At the onset of summer, there was a sharp decrease in stomatal conductance (g(s)) in girdled trees followed by a full recovery after the first major rainfall in September. Eliminating the root as a carbohydrate sink by girdling induced a rapid reversible reduction in g(s). Respiratory potential (a laboratory measure of tissue-level respiration) increased above the girdle (branches and upper trunk) and decreased below the girdle (lower trunk and roots) relative to control trees during the growing season, but the effect was reversed after the first major rainfall. The increase in branch respiratory potential induced by girdling suggests that the decrease in g(s) was caused by the accumulation of carbohydrates above the girdle, which is consistent with an observed increase in leaf mass per area in the girdled trees. Trunk girdling did not affect native xylem embolism or xylem conductivity. Both treated and control trunks experienced loss of xylem conductivity ranging from 10% in spring to 30% in summer. Girdling reduced xylem growth and sapwood to leaf area ratio, which in turn reduced branch leaf specific conductivity (LSC). The girdling-induced reductions in g(s) and transpiration were associated with a decrease in leaf hydraulic conductance. Two years after girdling, when root-to-shoot phloem continuity had been restored, girdled trees had a reduced density of new wood, which increased xylem conductivity and whole-tree LSC, but also vulnerability to embolism.

  16. Doubling the CO{sub 2} concentration enhanced the activity of carbohydrate-metabolism enzymes, source carbohydrate production, photoassimilate transport, and sink strength for Opuntia ficus-indica

    SciTech Connect

    Wang, Ning; Nobel, P.S.

    1996-03-01

    After exposure to a doubled CO{sub 2} concentration of 750 {mu}mol mol{sup -1} air for about 3 months, glucose and starch in the chlorenchyma of basal cladodes of Opuntia ficus-indica increased 175 and 57%, respectively, compared with the current CO{sub 2} concentration of 370 {mu}mol mol{sup -1}, but sucrose content was virtually unaffected. Doubling the CO{sub 2} concentration increased the noncturnal malate production in basal cladodes by 75%, inorganic phosphate (Pi) by 32% soluble starch synthase activity by 30%, and sucrose-Pi synthase activity by 146%, but did not affect the activity of hexokinase. Doubling CO{sub 2} accelerated phloem transport of sucrose out of the basal cladodes, resulting in a 73% higher dry weight for the daughter cladodes. Doubling CO{sub 2} increased the glucose content in 14-d-old daughter cladodes by 167%, increased nocturnal malate production by 22%, decreased total amino acid content by 61%, and increased soluble starch synthase activity by 30% and sucrose synthase activity by 62%. No downward acclimation of photosynthesis during long-term exposure to elevated CO{sub 2} concentrations occurs for O. ficus-indica, consistent with its higher source capacity and sink strength than under current CO{sub 2}. These changes apparently do not result in Pi limitation of photosynthesis or suppression of genes governing photosynthesis for this perennial Crassulacean acid metabolism species, as occur for some annual crops.

  17. Proteomic analysis of Arabidopsis thaliana leaves in response to acute boron deficiency and toxicity reveals effects on photosynthesis, carbohydrate metabolism, and protein synthesis.

    PubMed

    Chen, Mei; Mishra, Sasmita; Heckathorn, Scott A; Frantz, Jonathan M; Krause, Charles

    2014-02-15

    Boron (B) stress (deficiency and toxicity) is common in plants, but as the functions of this essential micronutrient are incompletely understood, so too are the effects of B stress. To investigate mechanisms underlying B stress, we examined protein profiles in leaves of Arabidopsis thaliana plants grown under normal B (30 μM), compared to plants transferred for 60 and 84 h (i.e., before and after initial visible symptoms) in deficient (0 μM) or toxic (3 mM) levels of B. B-responsive polypeptides were sequenced by mass spectrometry, following 2D gel electrophoresis, and 1D gels and immunoblotting were used to confirm the B-responsiveness of some of these proteins. Fourteen B-responsive proteins were identified, including: 9 chloroplast proteins, 6 proteins of photosynthetic/carbohydrate metabolism (rubisco activase, OEC23, photosystem I reaction center subunit II-1, ATPase δ-subunit, glycolate oxidase, fructose bisphosphate aldolase), 6 stress proteins, and 3 proteins involved in protein synthesis (note that the 14 proteins may fall into multiple categories). Most (8) of the B-responsive proteins decreased under both B deficiency and toxicity; only 3 increased with B stress. Boron stress decreased, or had no effect on, 3 of 4 oxidative stress proteins examined, and did not affect total protein. Hence, our results indicate relatively early specific effects of B stress on chloroplasts and protein synthesis.

  18. Altered carbohydrate, lipid, and xenobiotic metabolism by liver from rats flown on Cosmos 1887

    NASA Technical Reports Server (NTRS)

    Merrill, A. H. Jr; Hoel, M.; Wang, E.; Mullins, R. E.; Hargrove, J. L.; Jones, D. P.; Popova, I. A.; Merrill AH, J. r. (Principal Investigator)

    1990-01-01

    To determine the possible biochemical effects of prolonged weightlessness on liver function, samples of liver from rats that had flown aboard Cosmos 1887 were analyzed for protein, glycogen, and lipids as well as the activities of a number of key enzymes involved in metabolism of these compounds and xenobiotics. Among the parameters measured, the major differences were elevations in the glycogen content and hydroxymethylglutaryl-CoA (HMG-CoA) reductase activities for the rats flown on Cosmos 1887 and decreases in the amount of microsomal cytochrome P-450 and the activities of aniline hydroxylase and ethylmorphine N-demethylase, cytochrome P-450-dependent enzymes. These results support the earlier finding of differences in these parameters and suggest that altered hepatic function could be important during spaceflight and/or the postflight recovery period.

  19. LuxS-Based Signaling in Streptococcus gordonii: Autoinducer 2 Controls Carbohydrate Metabolism and Biofilm Formation with Porphyromonas gingivalis

    PubMed Central

    McNab, Roderick; Ford, Suzannah K.; El-Sabaeny, Azza; Barbieri, Bruno; Cook, Guy S.; Lamont, Richard J.

    2003-01-01

    Communication based on autoinducer 2 (AI-2) is widespread among gram-negative and gram-positive bacteria, and the AI-2 pathway can control the expression of genes involved in a variety of metabolic pathways and pathogenic mechanisms. In the present study, we identified luxS, a gene responsible for the synthesis of AI-2, in Streptococcus gordonii, a major component of the dental plaque biofilm. S. gordonii conditioned medium induced bioluminescence in an AI-2 reporter strain of Vibrio harveyi. An isogenic mutant of S. gordonii, generated by insertional inactivation of the luxS gene, was unaffected in growth and in its ability to form biofilms on polystyrene surfaces. In contrast, the mutant strain failed to induce bioluminescence in V. harveyi and was unable to form a mixed species biofilm with a LuxS-null strain of the periodontal pathogen Porphyromonas gingivalis. Complementation of the luxS mutation in S. gordonii restored normal biofilm formation with the luxS-deficient P. gingivalis. Differential display PCR demonstrated that the inactivation of S. gordonii luxS downregulated the expression of a number of genes, including gtfG, encoding glucosyltransferase; fruA, encoding extracellular exo-β-d-fructosidase; and lacD encoding tagatose 1,6-diphosphate aldolase. However, S. gordonii cell surface expression of SspA and SspB proteins, previously implicated in mediating adhesion between S. gordonii and P. gingivalis, was unaffected by inactivation of luxS. The results suggest that S. gordonii produces an AI-2-like signaling molecule that regulates aspects of carbohydrate metabolism in the organism. Furthermore, LuxS-dependent intercellular communication is essential for biofilm formation between nongrowing cells of P. gingivalis and S. gordonii. PMID:12486064

  20. Effects of Aerobic Exercise on Postprandial Carbohydrate and Lipoprotein Metabolism Following Cookie Ingestion in Healthy Young Women.

    PubMed

    Hashimoto, Sayuki; Mizutani, Erika; Suzuki, Maiko; Yoshida, Akihiro; Naito, Michitaka

    2015-01-01

    We examined the acute effects of postprandial aerobic exercise on glucose and lipid metabolism following cookie ingestion. Fifteen healthy young women with a sedentary lifestyle, normal weight and apolipoprotein E3/3 participated. After a 12-h overnight fast, each subject ingested a cookie (1.53 g/kg, Meal Test C) and then performed two trials, one with postprandial exercise (E trial) and one without exercise (C trial), in a randomized crossover design. A single 30-min bout of walking exercise was performed 20 min after the cookie intake. Venous blood samples were drawn before (0 h) and 20 min and 1, 2, 4, and 6 h after cookie ingestion. The Δglucose concentration was not significantly different between the two trials, but the Δinsulin concentration at 1 h and the incremental area under the curve (IAUC) (0-2 h)-insulin in the E trial were significantly lower than in the C trial. The ratio of glucose/insulin at 1 h was significantly higher in the E trial than in the C trial. The ΔTG, ΔRLP-TG, ΔapoB48 and ΔRemL-C concentrations at 1 h in the E trial were significantly higher than in the C trial. The IAUC (0-2 h)-apoB48 in the E trial was significantly larger than in the C trial. Postprandial exercise showed an insulin-sparing effect following the cookie ingestion by increasing insulin sensitivity. However, postprandial exercise transiently stimulated the secretion of exogenous apoB48-containing lipoprotein during the early period, and no further effects were observed. These results suggest that postprandial aerobic exercise is effective for the promotion of postprandial carbohydrate metabolism, but not lipidemia.

  1. Effect of low carbohydrate high protein (LCHP) diet on lipid metabolism, liver and kidney function in rats.

    PubMed

    Kostogrys, Renata B; Franczyk-Żarów, Magdalena; Maślak, Edyta; Topolska, Kinga

    2015-03-01

    The objective of this study was to compare effects of Western diet (WD) with low carbohydrate high protein (LCHP) diet on lipid metabolism, liver and kidney function in rats. Eighteen rats were randomly assigned to three experimental groups and fed for the next 2 months. The experimental diets were: Control (7% of soybean oil, 20% protein), WD (21% of butter, 20% protein), and LCHP (21% of butter and 52.4% protein) diet. The LCHP diet significantly decreased the body weight of the rats. Diet consumption was differentiated among groups, however significant changes were observed since third week of the experiment duration. Rats fed LCHP diet ate significantly less (25.2g/animal/day) than those from Control (30.2g/animal/day) and WD (27.8 g/animal/day) groups. Additionally, food efficiency ratio (FER) tended to decrease in LCHP fed rats. Serum homocysteine concentration significantly decreased in rats fed WD and LCHP diets. Liver weights were significantly higher in rats fed WD and LCHP diets. At the end of the experiment (2 months) the triacylglycerol (TAG) was significantly decreased in animals fed LCHP compared to WD. qRT-PCR showed that SCD-1 and FAS were decreased in LCHP fed rats, but WD diet increased expression of lipid metabolism genes. Rats receiving LCHP diet had two fold higher kidney weight and 54.5% higher creatinin level compared to Control and WD diets. In conclusion, LCHP diet decreased animal's body weight and decreased TAG in rat's serum. However, kidney damage in LCHP rats was observed.

  2. Effects of Dietary Fibers on Weight Gain, Carbohydrate Metabolism and Gastric Ghrelin Gene Expression in High Fat Diet Fed Mice

    PubMed Central

    Wang, Zhong Q.; Zuberi, Aamir; Zhang, Xian H.; Macgowan, Jacalyn; Qin, Jianhua; Ye, Xin; Son, Leslie; Wu, Qinglin; Lian, Kun; Cefalu, William T.

    2009-01-01

    Diets that are high in dietary fiber are reported to have substantial health benefits. We sought to compare the metabolic effects for three types of dietary fibers, i.e. sugar cane fiber (SCF), psyllium (PSY) and cellulose (CEL) on body weight, carbohydrate metabolism and stomach ghrelin gene expression in a high-fat diet fed mouse model. Thirty-six male mice (C57BL/6) were randomly divided into four groups that consumed high fat-diets or high fat diet containing 10% SCF, PSY, and CEL respectively. After baseline measurements were assessed for body weight, plasma insulin, glucose, leptin and glucagon-like peptide-1 (GLP-1), animals were treated for 12 weeks. Parameters were re-evaluated at end of study. Whereas there was no difference at the baseline, body weight gains in the PSY and SCF groups were significantly lower than in CEL group at end of study, No difference in body weight was observed between the PSY and SCF animals. Body composition analysis demonstrated that fat mass in the SCF group was considerably lower than in the CEL and HFD groups. In addition, fasting plasma glucose and insulin and areas under curve of IPGTT were also significantly lower in the SCF and PSY groups than in the CEL and HFD groups. Moreover, fasting plasma concentrations of leptin were significantly lower and GLP-1 level was two-fold higher in the SCF and PSY mice than in the HFD and CEL mice. Ghrelin mRNA levels of stomach in SCF groups were significantly lower than in CEL and HFD groups as well. These results suggest differences in response to dietary fiber intake in this animal model as high fat diets incorporating dietary fibers such as SCF and PSY appeared to attenuate weight gain, enhance insulin sensitivity, and modulate leptin and GLP-1 secretion and gastric ghrelin gene expression. PMID:17998014

  3. Prolonged postdiapause: influence on some indicators of carbohydrate and lipid metabolism of the red mason bee, Osmia rufa.

    PubMed

    Dmochowska, Kamila; Giejdasz, Karol; Fliszkiewicz, Monika; Zółtowska, Krystyna

    2013-01-01

    Bees of the genus Osmia are being used in crop pollination at an increasing rate. However, a short life expectancy of adult individuals limits the feasibility of their use. Cocoons of the red mason bee, Osmia rufa L. (Hymenoptera: Megachilidae), can be stored at 4° C in a postdiapause state, and adult bees can be used for pollination outside their natural flight period. The period of storage in this form has an unfavorable influence on the survival rate, life expectancy, and fertility of the bee. It was suggested that the negative results are connected with exhaustion of energy reserves. To test this hypothesis, the present study examined the contents of protein, carbohydrates, lipids, and the activities of some enzymes, and their degradation in red mason bees that emerged in spring according to their biological clock and in summer after elongated diapause. It was found that postdiapause artificially elongated by 3 months caused significant decreases in body weight, total sugar, glycogen, lipids, and protein content in O. rufa. Glucose level was highest in bees that emerged in the summer, which was coincident with increased activities of maltase and trehalase. The activities of sucrase and cellobiase were not changed, while amylase activity was considerably decreased. The activities of triacylglycerols lipase and C2, C4, C10 carboxylesterases were highest in bees that emerged in July. Low temperatures restrict O. rufa emergence, and during prolonged postdiapause, metabolic processes lead to significant reductions of structural and energetic compounds.

  4. Prolonged Postdiapause: Influence on some Indicators of Carbohydrate and Lipid Metabolism of the Red Mason Bee, Osmia rufa

    PubMed Central

    Dmochowska, Kamila; Giejdasz, Karol; Fliszkiewicz, Monika; Żółtowska, Krystyna

    2013-01-01

    Bees of the genus Osmia are being used in crop pollination at an increasing rate. However, a short life expectancy of adult individuals limits the feasibility of their use. Cocoons of the red mason bee, Osmia rufa L. (Hymenoptera: Megachilidae), can be stored at 4° C in a postdiapause state, and adult bees can be used for pollination outside their natural flight period. The period of storage in this form has an unfavorable influence on the survival rate, life expectancy, and fertility of the bee. It was suggested that the negative results are connected with exhaustion of energy reserves. To test this hypothesis, the present study examined the contents of protein, carbohydrates, lipids, and the activities of some enzymes, and their degradation in red mason bees that emerged in spring according to their biological clock and in summer after elongated diapause. It was found that postdiapause artificially elongated by 3 months caused significant decreases in body weight, total sugar, glycogen, lipids, and protein content in O. rufa. Glucose level was highest in bees that emerged in the summer, which was coincident with increased activities of maltase and trehalase. The activities of sucrase and cellobiase were not changed, while amylase activity was considerably decreased. The activities of triacylglycerols lipase and C2, C4, C10 carboxylesterases were highest in bees that emerged in July. Low temperatures restrict O. rufa emergence, and during prolonged postdiapause, metabolic processes lead to significant reductions of structural and energetic compounds. PMID:24219557

  5. Exercise and postprandial lipid metabolism: an update on potential mechanisms and interactions with high-carbohydrate diets (review).

    PubMed

    Gill, Jason M R; Hardman, Adrianne E

    2003-03-01

    Endurance trained people exhibit low levels of postprandial lipemia. However, this favorable situation is rapidly reversed with de-training and it is likely that the triglyceride (TG) lowering effects of exercise are mainly the result of acute metabolic responses to recent exercise rather than long-term training adaptations. A large body of evidence suggests that postprandial lipemia can be attenuated following an individual exercise session, with the energy expended during exercise being an important determinant of the extent of TG lowering. Increased lipoprotein lipase-mediated TG clearance and reduced hepatic TG secretion are both likely to contribute to the exercise-induced TG reductions. These changes may occur in response to post-exercise substrate deficits in skeletal muscle and/or the liver. In addition, regular exercise can oppose the hypertriglyceridaemia sometimes seen with low-fat, high-carbohydrate diets. Levels of physical activity should therefore be taken into account when considering nutritional strategies for reducing the risk of cardiovascular disease.

  6. Comparative Genomics Revealed Genetic Diversity and Species/Strain-Level Differences in Carbohydrate Metabolism of Three Probiotic Bifidobacterial Species

    PubMed Central

    Odamaki, Toshitaka; Horigome, Ayako; Sugahara, Hirosuke; Hashikura, Nanami; Minami, Junichi; Xiao, Jin-zhong; Abe, Fumiaki

    2015-01-01

    Strains of Bifidobacterium longum, Bifidobacterium breve, and Bifidobacterium animalis are widely used as probiotics in the food industry. Although numerous studies have revealed the properties and functionality of these strains, it is uncertain whether these characteristics are species common or strain specific. To address this issue, we performed a comparative genomic analysis of 49 strains belonging to these three bifidobacterial species to describe their genetic diversity and to evaluate species-level differences. There were 166 common clusters between strains of B. breve and B. longum, whereas there were nine common clusters between strains of B. animalis and B. longum and four common clusters between strains of B. animalis and B. breve. Further analysis focused on carbohydrate metabolism revealed the existence of certain strain-dependent genes, such as those encoding enzymes for host glycan utilisation or certain membrane transporters, and many genes commonly distributed at the species level, as was previously reported in studies with limited strains. As B. longum and B. breve are human-residential bifidobacteria (HRB), whereas B. animalis is a non-HRB species, several of the differences in these species' gene distributions might be the result of their adaptations to the nutrient environment. This information may aid both in selecting probiotic candidates and in understanding their potential function as probiotics. PMID:26236711

  7. Reducing properties, energy efficiency and carbohydrate metabolism in hyperhydric and normal carnation shoots cultured in vitro: a hypoxia stress?

    PubMed

    Saher, Shady; Fernández-García, Nieves; Piqueras, Abel; Hellín, Eladio; Olmos, Enrique

    2005-06-01

    Hyperhydricity is considered as a physiological disorder that can be induced by different stressing conditions. In the present work we have studied the metabolic and energetic states of hyperhydric carnation shoots. We have evaluated the hypothesis that hypoxia stress is the main factor affecting the metabolism of hyperhydric leaves. Our results indicate a low level of ATP in hyperhydric tissues, but only slight modifications in pyridine nucleotide contents. Concurrently, the glucose-6-phosphate dehydrogenase (G-6-PDH; EC 1.1.1.49) activity in hyperhydric leaves was increased but glucokinase (GK; EC 2.7.1.2) activity was unchanged. We have observed that the metabolism of pyruvate was altered in hyperhydric tissues by the induction of pyruvate synthesis via NADP-dependent malic enzyme (EC 1.1.1.40). The enzymes of the fermentative metabolism pyruvate decarboxylase (PDC; EC 4.1.1.1) and alcohol dehydrogenase (ADH; EC 1.1.1.1) were highly increased in hyperhydric leaves. Sucrose metabolism was modified in hyperhydric leaves with a high increase in the activity of both synthesis and catabolic enzymes. The analysis of the sucrose, glucose and fructose contents indicated that all of these sugars were accumulated in hyperhydric leaves. However, the pinitol content was drastically decreased in hyperhydric leaves. We consider that these results suggest that hyperhydric leaves of carnation have adapted to hypoxia stress conditions by the induction of the oxidative pentose phosphate and fermentative pathways.

  8. Rice alcohol dehydrogenase 1 promotes survival and has a major impact on carbohydrate metabolism in the embryo and endosperm when seeds are germinated in partially oxygenated water

    PubMed Central

    Takahashi, Hirokazu; Greenway, Hank; Matsumura, Hideo; Tsutsumi, Nobuhiro; Nakazono, Mikio

    2014-01-01

    Background and Aims Rice (Oryza sativa) has the rare ability to germinate and elongate a coleoptile under oxygen-deficient conditions, which include both hypoxia and anoxia. It has previously been shown that ALCOHOL DEHYDROGENASE 1 (ADH1) is required for cell division and cell elongation in the coleoptile of submerged rice seedlings by means of studies using a rice ADH1-deficient mutant, reduced adh activity (rad). The aim of this study was to understand how low ADH1 in rice affects carbohydrate metabolism in the embryo and endosperm, and lactate and alanine synthesis in the embryo during germination and subsequent coleoptile growth in submerged seedlings. Methods Wild-type and rad mutant rice seeds were germinated and grown under complete submergence. At 1, 3, 5 and 7 d after imbibition, the embryo and endosperm were separated and several of their metabolites were measured and compared. Key results In the rad embryo, the rate of ethanol fermentation was halved, while lactate and alanine concentrations were 2·4- and 5·7- fold higher in the mutant than in the wild type. Glucose and fructose concentrations in the embryos increased with time in the wild type, but not in the rad mutant. The rad mutant endosperm had lower amounts of the α-amylases RAMY1A and RAMY3D, resulting in less starch degradation and lower glucose concentrations. Conclusions These results suggest that ADH1 is essential for sugar metabolism via glycolysis to ethanol fermentation in both the embryo and endosperm. In the endosperm, energy is presumably needed for synthesis of the amylases and for sucrose synthesis in the endosperm, as well as for sugar transport to the embryo. PMID:24431339

  9. Regulation of carbohydrate metabolism by 2,5-anhydro-D-mannitol.

    PubMed Central

    Riquelme, P T; Wernette-Hammond, M E; Kneer, N M; Lardy, H A

    1983-01-01

    In hepatocytes isolated from fasted rats, 2,5-anhydromannitol inhibits gluconeogenesis from lactate plus pyruvate and from substrates that enter the gluconeogenic pathway as triose phosphate. This fructose analog has no effect, however, on gluconeogenesis from xylitol, a substrate that enters the pathway primarily as fructose 6-phosphate. The sensitivity of gluconeogenesis to 2,5-anhydromannitol depends on the substrate metabolized; concentrations of 2,5-anhydromannitol required for 50% inhibition increase in the order lactate plus pyruvate less than dihydroxyacetone less than glycerol less than sorbitol less than fructose. The inhibition by 2,5-anhydromannitol of gluconeogenesis from dihydroxyacetone is accompanied by an increase in lactate formation and by two distinct crossovers in gluconeogenic-glycolytic metabolite patterns-i.e., increases in pyruvate concentrations with decreases in phosphoenolpyruvate and increases in fructose-1,6-bisphosphate concentrations with little change in fructose 6-phosphate. In addition, 2,5-anhydromannitol blocks the ability of glucagon to stimulate gluconeogenesis and inhibit lactate production from dihydroxyacetone. 2,5-Anhydromannitol decreases cellular fructose 2,6-bisphosphate content in hepatocytes; therefore the effects of the fructose analog are not mediated by fructose 2,6-bisphosphate, a naturally occurring allosteric regulator. 2,5-Anhydromannitol also inhibits gluconeogenesis in hepatocytes isolated from fasted diabetic rats, but higher concentrations of the analog are required. PMID:6410389

  10. RNA Sequencing Reveals Xyr1 as a Transcription Factor Regulating Gene Expression beyond Carbohydrate Metabolism

    PubMed Central

    Ma, Liang; Chen, Ling; Zhang, Lei; Zou, Gen; Liu, Rui; Jiang, Yanping

    2016-01-01

    Xyr1 has been demonstrated to be the main transcription activator of (hemi)cellulases in the well-known cellulase producer Trichoderma reesei. This study comprehensively investigates the genes regulated by Xyr1 through RNA sequencing to produce the transcription profiles of T. reesei Rut-C30 and its xyr1 deletion mutant (Δxyr1), cultured on lignocellulose or glucose. xyr1 deletion resulted in 467 differentially expressed genes on inducing medium. Almost all functional genes involved in (hemi)cellulose degradation and many transporters belonging to the sugar porter family in the major facilitator superfamily (MFS) were downregulated in Δxyr1. By contrast, all differentially expressed protease, lipase, chitinase, some ATP-binding cassette transporters, and heat shock protein-encoding genes were upregulated in Δxyr1. When cultured on glucose, a total of 281 genes were expressed differentially in Δxyr1, most of which were involved in energy, solute transport, lipid, amino acid, and monosaccharide as well as secondary metabolism. Electrophoretic mobility shift assays confirmed that the intracellular β-glucosidase bgl2, the putative nonenzymatic cellulose-attacking gene cip1, the MFS lactose transporter lp, the nmrA-like gene, endo T, the acid protease pepA, and the small heat shock protein hsp23 were probable Xyr1-targets. These results might help elucidate the regulation system for synthesis and secretion of (hemi)cellulases in T. reesei Rut-C30. PMID:28116297

  11. Carbohydrate metabolism in photosynthetic and nonphotosynthetic tissues of variegated leaves of Coleus blumei Benth

    SciTech Connect

    Madore, M.A. )

    1990-06-01

    Mature, variegated leaves of Coleus blumei Benth. contained stachyose and other raffinose series sugars in both green, photosynthetic and white, nonphotosynthetic tissues. However, unlike the green tissues, white tissues had no detectable level of galactinol synthase activity and a low level of sucrose phosphate synthase indicating that stachyose and possibly sucrose present in white tissues may have originated in green tissues. Uptake of exogenously supplied ({sup 14}C)stachyose or ({sup 14}C)sucrose into either tissue type showed conventional kinetic profiles indicating combined operation of liner first-order and saturable systems. Autoradiographs of white discs showed no detectable minor vein labeling with ({sup 14}C)stachyose, but some degree of vein labeling with ({sup 14}C)sucrose. Autoradiographs of green discs showed substantial vein loading with either sugar. In both tissues, p-chloromercuribenzenesulfonic acid had no effect on the linear component of sucrose or stachyose uptake but inhibited the saturable component. Both tissues contained high levels of invertase, sucrose synthase and {alpha}-galactosidase and extensively metabolized exogenously supplied {sup 14}C-sugars. In green tissues, label from exogenous sugars was recovered as raffinose-series sugars. In white tissues, exogenous sugars were hydrolyzed and converted to amino acids and organic acids. The results indicate that variegated Coleus leaves may be useful for studies on both phloem loading and phloem unloading processes in stachyose-transporting species.

  12. Doubling the CO2 Concentration Enhanced the Activity of Carbohydrate-Metabolism Enzymes, Source Carbohydrate Production, Photoassimilate Transport, and Sink Strength for Opuntia ficus-indica.

    PubMed Central

    Wang, N.; Nobel, P. S.

    1996-01-01

    After exposure to a doubled CO2 concentration of 750 [mu]mol mol-1 air for about 3 months glucose and starch in the chlorenchyma of basal cladodes of Opuntia ficus-indica increased 175 and 57%, respectively, compared with the current CO2 concentration of 370 [mu]mol mol-1, but sucrose content was virtually unaffected. Doubling the CO2 concentration increased the nocturnal malate production in basal cladodes by 75%, inorganic phosphate (Pi) by 32%, soluble starch synthase activity by 30%, and sucrose-Pi synthase activity by 146%, but did not affect the activity of hexokinase. Doubling CO2 accelerated phloem transport of sucrose out of the basal cladodes, resulting in a 73% higher dry weight for the daughter cladodes. Doubling CO2 increased the glucose content in 14-d-old daughter cladodes by 167%, increased nocturnal malate production by 22%, decreased total amino acid content by 61%, and increased soluble starch synthase activity by 30% and sucrose synthase activity by 62%. No downward acclimation of photosynthesis during long-term exposure to elevated CO2 concentrations occurs for O. ficus-indica (M. Cui, P.M. Miller, P.S. Nobel [1993] Plant Physiol 103: 519-524; P.S. Nobel, A.A. Israel [1994] J Exp Bot 45: 295-303), consistent with its higher source capacity and sink strength than under current CO2. These changes apparently do not result in Pi limitation of photosynthesis or suppression of genes governing photosynthesis for this perennial Crassulacean acid metabolism species, as occur for some annual crops. PMID:12226228

  13. Doubling the CO2 Concentration Enhanced the Activity of Carbohydrate-Metabolism Enzymes, Source Carbohydrate Production, Photoassimilate Transport, and Sink Strength for Opuntia ficus-indica.

    PubMed

    Wang, N.; Nobel, P. S.

    1996-03-01

    After exposure to a doubled CO2 concentration of 750 [mu]mol mol-1 air for about 3 months glucose and starch in the chlorenchyma of basal cladodes of Opuntia ficus-indica increased 175 and 57%, respectively, compared with the current CO2 concentration of 370 [mu]mol mol-1, but sucrose content was virtually unaffected. Doubling the CO2 concentration increased the nocturnal malate production in basal cladodes by 75%, inorganic phosphate (Pi) by 32%, soluble starch synthase activity by 30%, and sucrose-Pi synthase activity by 146%, but did not affect the activity of hexokinase. Doubling CO2 accelerated phloem transport of sucrose out of the basal cladodes, resulting in a 73% higher dry weight for the daughter cladodes. Doubling CO2 increased the glucose content in 14-d-old daughter cladodes by 167%, increased nocturnal malate production by 22%, decreased total amino acid content by 61%, and increased soluble starch synthase activity by 30% and sucrose synthase activity by 62%. No downward acclimation of photosynthesis during long-term exposure to elevated CO2 concentrations occurs for O. ficus-indica (M. Cui, P.M. Miller, P.S. Nobel [1993] Plant Physiol 103: 519-524; P.S. Nobel, A.A. Israel [1994] J Exp Bot 45: 295-303), consistent with its higher source capacity and sink strength than under current CO2. These changes apparently do not result in Pi limitation of photosynthesis or suppression of genes governing photosynthesis for this perennial Crassulacean acid metabolism species, as occur for some annual crops.

  14. Protective effect of bioflavonoid myricetin enhances carbohydrate metabolic enzymes and insulin signaling molecules in streptozotocin-cadmium induced diabetic nephrotoxic rats.

    PubMed

    Kandasamy, Neelamegam; Ashokkumar, Natarajan

    2014-09-01

    Diabetic nephropathy is the kidney disease that occurs as a result of diabetes. The present study was aimed to evaluate the therapeutic potential of myricetin by assaying the activities of key enzymes of carbohydrate metabolism, insulin signaling molecules and renal function markers in streptozotocin (STZ)-cadmium (Cd) induced diabetic nephrotoxic rats. After myricetin treatment schedule, blood and tissue samples were collected to determine plasma glucose, insulin, hemoglobin, glycosylated hemoglobin and renal function markers, carbohydrate metabolic enzymes in the liver and insulin signaling molecules in the pancreas and skeletal muscle. A significant increase of plasma glucose, glycosylated hemoglobin, urea, uric acid, creatinine, blood urea nitrogen (BUN), urinary albumin, glycogen phosphorylase, glucose-6-phosphatase, and fructose-1,6-bisphosphatase and a significant decrease of plasma insulin, hemoglobin, hexokinase, glucose-6-phosphate dehydrogenase, glycogen and glycogen synthase with insulin signaling molecule expression were found in the STZ-Cd induced diabetic nephrotoxic rats. The administration of myricetin significantly normalizes the carbohydrate metabolic products like glucose, glycated hemoglobin, glycogen phosphorylase and gluconeogenic enzymes and renal function markers with increase insulin, glycogen, glycogen synthase and insulin signaling molecule expression like glucose transporter-2 (GLUT-2), glucose transporter-4 (GLUT-4), insulin receptor-1 (IRS-1), insulin receptor-2 (IRS-2) and protein kinase B (PKB). Based on the data, the protective effect of myricetin was confirmed by its histological annotation of the pancreas, liver and kidney tissues. These findings suggest that myricetin improved carbohydrate metabolism which subsequently enhances glucose utilization and renal function in STZ-Cd induced diabetic nephrotoxic rats.

  15. Ameliorating effect of mother tincture of Syzygium jambolanum on carbohydrate and lipid metabolic disorders in streptozotocin-induced diabetic rat: Homeopathic remedy

    PubMed Central

    Maiti, Soumyajit; Ali, Kazi M.; Jana, Kishalay; Chatterjee, Kausik; De, Debasis; Ghosh, Debidas

    2013-01-01

    Background: Syzygium jambolanum (S jambolanum) is widely used in homeopathy for treating patients with diabetes mellitus. In the present study, an attempt has been made to investigate the remedial effect of homeopathic drug S jambolanum on carbohydrate and lipid metabolic disorders on streptozotocin induced diabetic rat. Materials and Methods: Diabetes induction in Wistar strain rat was performed as per standard method using streptozotocin at the dose of 4 mg/100 gm body weight. Activities of carbohydrate metabolic enzymes in hepatic tissue, and glycogen content in hepatic and muscular tissues were assessed biochemically following the standard protocols. Serum lipid profile level and activities of GOT and GPT in serum were measured as per standard method using specific kits. Results: The homeopathic drug, mother tincture of S jambolanum significantly decreased fasting blood glucose levels and improved carbohydrate metabolic key enzyme activities in hepatic tissue i.e., hexokinase, glucose-6-phosphate dehydrogenase and glucose-6-phosphatase in diabetic rats. Alongside, serum lipid profile biomarkers i.e., triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDLc), very low density lipoprotein cholesterol (VLDLc) and high density lipoprotein cholesterol (HDLc) levels were significantly ameliorated in homeopathic drug supplemented diabetic animals in compared with the untreated diabetic animal. Side by side, the S jambolanum has the capacity to attenuate diabetes induced hepatic injury in model animal, which has been assessed here by the recovery of GOT and GPT activities in serum of drug treated diabetic animal. Conclusion: The result of the present study indicated that the homeopathic drug S jambolanum (mother tincture) has a protective effect on diabetic induced carbohydrate and lipid metabolic disorders in STZ-induced diabetic animal. PMID:23633838

  16. Protective effect of bioflavonoid myricetin enhances carbohydrate metabolic enzymes and insulin signaling molecules in streptozotocin–cadmium induced diabetic nephrotoxic rats

    SciTech Connect

    Kandasamy, Neelamegam; Ashokkumar, Natarajan

    2014-09-01

    Diabetic nephropathy is the kidney disease that occurs as a result of diabetes. The present study was aimed to evaluate the therapeutic potential of myricetin by assaying the activities of key enzymes of carbohydrate metabolism, insulin signaling molecules and renal function markers in streptozotocin (STZ)–cadmium (Cd) induced diabetic nephrotoxic rats. After myricetin treatment schedule, blood and tissue samples were collected to determine plasma glucose, insulin, hemoglobin, glycosylated hemoglobin and renal function markers, carbohydrate metabolic enzymes in the liver and insulin signaling molecules in the pancreas and skeletal muscle. A significant increase of plasma glucose, glycosylated hemoglobin, urea, uric acid, creatinine, blood urea nitrogen (BUN), urinary albumin, glycogen phosphorylase, glucose-6-phosphatase, and fructose-1,6-bisphosphatase and a significant decrease of plasma insulin, hemoglobin, hexokinase, glucose-6-phosphate dehydrogenase, glycogen and glycogen synthase with insulin signaling molecule expression were found in the STZ–Cd induced diabetic nephrotoxic rats. The administration of myricetin significantly normalizes the carbohydrate metabolic products like glucose, glycated hemoglobin, glycogen phosphorylase and gluconeogenic enzymes and renal function markers with increase insulin, glycogen, glycogen synthase and insulin signaling molecule expression like glucose transporter-2 (GLUT-2), glucose transporter-4 (GLUT-4), insulin receptor-1 (IRS-1), insulin receptor-2 (IRS-2) and protein kinase B (PKB). Based on the data, the protective effect of myricetin was confirmed by its histological annotation of the pancreas, liver and kidney tissues. These findings suggest that myricetin improved carbohydrate metabolism which subsequently enhances glucose utilization and renal function in STZ–Cd induced diabetic nephrotoxic rats. - Highlights: • Diabetic rats are more susceptible to cadmium nephrotoxicity. • Cadmium plays as a cumulative

  17. The Choice of Euthanasia Method Affects Metabolic Serum Biomarkers.

    PubMed

    Paula, Pierozan; Fredrik, Jernerén; Yusuf, Ransome; Oskar, Karlsson

    2017-02-28

    The impact of euthanasia methods on endocrine and metabolic parameters in rodent tissues and biological fluids is highly relevant for the accuracy and reliability of the data collected. However, few studies concerning this issue are found in the literature. We compared the effects of three euthanasia methods currently used in animal experimentation (i.e. decapitation, CO2 inhalation, and pentobarbital injection) on the serum levels of corticosterone, insulin, glucose, triglycerides, cholesterol and a range of free fatty acids in rats. The corticosterone and insulin levels were not significantly affected by the euthanasia protocol used. However, euthanasia by an overdose of pentobarbital (120 mg/kg intraperitoneal injection) increased the serum levels of glucose, and decreased cholesterol, stearic and arachidonic acids levels compared with euthanasia by CO2 inhalation and decapitation. CO2 inhalation appears to increase the serum levels of triglycerides, while euthanasia by decapitation induced no individual discrepant biomarker level. We conclude that choice of the euthanasia methods are critical for the reliability of serum biomarkers and indicate the importance of selecting adequate euthanasia methods for metabolic analysis in rodents. Decapitation without anaesthesia may be the most adequate method of euthanasia when taking both animal welfare and data quality in consideration. This article is protected by copyright. All rights reserved.

  18. Integrated Management Strategies Increase Cottonseed, Oil and Protein Production: The Key Role of Carbohydrate Metabolism

    PubMed Central

    Yang, Hongkun; Zhang, Xinyue; Chen, Binglin; Meng, Yali; Wang, Youhua; Zhao, Wenqing; Zhou, Zhiguo

    2017-01-01

    Cottonseed, oil, and protein, as the by-products of cotton production, have the potential to provide commodities to meet the increasing demand of renewable bio-fuels and ruminant feed. An increase in crop yield per unit area requires high-yielding cultivar management with an economic nitrogen (N) rate, an optimal N application schedule, high-yielding plant populations and strong seedlings. Whether the integration of these agronomic practices into a coherent management system can increase the productivity of cotton fiber, embryo oil and protein requires experimental elucidation. In this 2-year study, conventional management practices (CM) were used as a control, and two integrated management strategies (IMS1 and IMS2) were considered at two soil fertility levels (high soil fertility and low soil fertility) to analyze the metabolic and biochemical traits of cotton embryos. The results illustrate that the cottonseed, oil, and protein yields for IMS1 and IMS2 were significantly higher than those under CM at both soil fertility levels and the fiber yield increased as well. The IMS regulated the maternal photo thermal environment by delaying the flowering date, resulting in increases in the seed weight. In developing cotton embryos, the IMS increased the embryo weight accumulation rate and biomass partitioning into oil and protein, which were associated with high activities of H+-ATPase, H+-PPase, sucrose synthase (SuSy), and cell wall invertase (C-INV) and low activities of sucrose phosphate synthase (SPS) and vacuole invertase (V-INV). Increased hexoses (D-fructose, D-glucose) content contributed to the oil and protein contents. These results suggest that increased sucrose/H+ symport, sucrose hydrolysis, hexoses synthesis, and cumulative photo-thermal product (PTP), especially in the early stage of embryo growth, play a dominant role in the high productivity of cotton oil and protein. PMID:28194156

  19. Misexpression of a Chloroplast Aspartyl Protease Leads to Severe Growth Defects and Alters Carbohydrate Metabolism in Arabidopsis1[C][W

    PubMed Central

    Paparelli, Eleonora; Gonzali, Silvia; Parlanti, Sandro; Novi, Giacomo; Giorgi, Federico M.; Licausi, Francesco; Kosmacz, Monika; Feil, Regina; Lunn, John E.; Brust, Henrike; van Dongen, Joost T.; Steup, Martin; Perata, Pierdomenico

    2012-01-01

    The crucial role of carbohydrate in plant growth and morphogenesis is widely recognized. In this study, we describe the characterization of nana, a dwarf Arabidopsis (Arabidopsis thaliana) mutant impaired in carbohydrate metabolism. We show that the nana dwarf phenotype was accompanied by altered leaf morphology and a delayed flowering time. Our genetic and molecular data indicate that the mutation in nana is due to a transfer DNA insertion in the promoter region of a gene encoding a chloroplast-located aspartyl protease that alters its pattern of expression. Overexpression of the gene (oxNANA) phenocopies the mutation. Both nana and oxNANA display alterations in carbohydrate content, and the extent of these changes varies depending on growth light intensity. In particular, in low light, soluble sugar levels are lower and do not show the daily fluctuations observed in wild-type plants. Moreover, nana and oxNANA are defective in the expression of some genes implicated in sugar metabolism and photosynthetic light harvesting. Interestingly, some chloroplast-encoded genes as well as genes whose products seem to be involved in retrograde signaling appear to be down-regulated. These findings suggest that the NANA aspartic protease has an important regulatory function in chloroplasts that not only influences photosynthetic carbon metabolism but also plastid and nuclear gene expression. PMID:22987884

  20. Plant maturity and nitrogen fertilization affected fructan metabolism in harvestable tissues of timothy (Phleum pratense L.).

    PubMed

    Ould-Ahmed, Marouf; Decau, Marie-Laure; Morvan-Bertrand, Annette; Prud'homme, Marie-Pascale; Lafrenière, Carole; Drouin, Pascal

    2014-10-15

    Timothy (Phleum pratense L.) is an important grass forage used for pasture, hay, and silage in regions with cool and humid growth seasons. One of the factors affecting the nutritive value of this grass is the concentration of non-structural carbohydrates (NSC), mainly represented by fructans. NSC concentration depends on multiple factors, making it hardly predictable. To provide a better understanding of NSC metabolism in timothy, the effects of maturity stage and nitrogen (N) fertilization level on biomass, NSC and N-compound concentrations were investigated in the tissues used for forage (leaf blades and stems surrounded by leaf sheaths) of hydroponically grown plants. Moreover, activities and relative expression level of enzymes involved in fructan metabolism were measured in the same tissues. Forage biomass was not altered by the fertilization level but was strongly modified by the stage of development. It increased from vegetative to heading stages while leaf-to-stem biomass ratio decreased. Total NSC concentration, which was not altered by N fertilization level, increased between heading and anthesis due to an accumulation of fructans in leaf blades. Fructan metabolizing enzyme activities (fructosyltransferase-FT and fructan exohydrolase-FEH) were not or only slightly altered by both maturity stage and N fertilization level. Conversely, the relative transcript levels of genes coding for enzymes involved in fructan metabolism were modified by N supply (PpFT1 and Pp6-FEH1) or maturity stage (PpFT2). The relative transcript level of PpFT1 was the highest in low N plants while that of Pp6-FEH1 was the highest in high N plants. Morevoer, transcript level of PpFT1 was negatively correlated with nitrate concentration while that of PpFT2 was positively correlated with sucrose concentration. This distinct regulation of the two genes coding for 6-sucrose:fructan fructosyltransferase (6-SFT) may allow a fine adequation of C allocation towards fructan synthesis in

  1. Ecologically Valid Carbohydrate Intake during Soccer-Specific Exercise Does Not Affect Running Performance in a Fed State

    PubMed Central

    Funnell, Mark P.; Dykes, Nick R.; Owen, Elliot J.; Mears, Stephen A.; Rollo, Ian; James, Lewis J.

    2017-01-01

    This study assessed the effect of carbohydrate intake on self-selected soccer-specific running performance. Sixteen male soccer players (age 23 ± 4 years; body mass 76.9 ± 7.2 kg; predicted VO2max = 54.2 ± 2.9 mL∙kg−1∙min−1; soccer experience 13 ± 4 years) completed a progressive multistage fitness test, familiarisation trial and two experimental trials, involving a modified version of the Loughborough Intermittent Shuttle Test (LIST) to simulate a soccer match in a fed state. Subjects completed six 15 min blocks (two halves of 45 min) of intermittent shuttle running, with a 15-min half-time. Blocks 3 and 6, allowed self-selection of running speeds and sprint times, were assessed throughout. Subjects consumed 250 mL of either a 12% carbohydrate solution (CHO) or a non-caloric taste matched placebo (PLA) before and at half-time of the LIST. Sprint times were not different between trials (CHO 2.71 ± 0.15 s, PLA 2.70 ± 0.14 s; p = 0.202). Total distance covered in self-selected blocks (block 3: CHO 2.07 ± 0.06 km; PLA 2.09 ± 0.08 km; block 6: CHO 2.04 ± 0.09 km; PLA 2.06 ± 0.08 km; p = 0.122) was not different between trials. There was no difference between trials for distance covered (p ≥ 0.297) or mean speed (p ≥ 0.172) for jogging or cruising. Blood glucose concentration was greater (p < 0.001) at the end of half-time during the CHO trial. In conclusion, consumption of 250 mL of 12% CHO solution before and at half-time of a simulated soccer match does not affect self-selected running or sprint performance in a fed state. PMID:28067762

  2. The improvement of large High-Density Lipoprotein (HDL) particle levels, and presumably HDL metabolism, depend on effects of low-carbohydrate diet and weight loss.

    PubMed

    Finelli, C; Crispino, P; Gioia, S; La Sala, N; D'amico, L; La Grotta, M; Miro, O; Colarusso, D

    2016-01-01

    Depressed levels of atheroprotective large HDL particles are common in obesity and cardiovascular disease (CVD). Increases in large HDL particles are favourably associated with reduced CVD event risk and coronary plaque burden. The objective of the study is to compare the effectiveness of low-carbohydrate diets and weight loss for increasing blood levels of large HDL particles at 1 year. This study was performed by screening for body mass index (BMI) and metabolic syndrome in 160 consecutive subjects referred to our out-patient Metabolic Unit in South Italy. We administered dietary advice to four small groups rather than individually. A single team comprised of a dietitian and physician administered diet-specific advice to each group. Large HDL particles at baseline and 1 year were measured using two-dimensional gel electrophoresis. Dietary intake was assessed via 3-day diet records. Although 1-year weight loss did not differ between diet groups (mean 4.4 %), increases in large HDL particles paralleled the degree of carbohydrate restriction across the four diets (p<0.001 for trend). Regression analysis indicated that magnitude of carbohydrate restriction (percentage of calories as carbohydrate at 1 year) and weight loss were each independent predictors of 1-year increases in large HDL concentration. Changes in HDL cholesterol concentration were modestly correlated with changes in large HDL particle concentration (r=0.47, p=.001). In conclusion, reduction of excess dietary carbohydrate and body weight improved large HDL levels. Comparison trials with cardiovascular outcomes are needed to more fully evaluate these findings.

  3. The improvement of large High-Density Lipoprotein (HDL) particle levels, and presumably HDL metabolism, depend on effects of low-carbohydrate diet and weight loss

    PubMed Central

    Finelli, C.; Crispino, P.; Gioia, S.; La Sala, N.; D'amico, L.; La Grotta, M.; Miro, O.; Colarusso, D.

    2016-01-01

    Depressed levels of atheroprotective large HDL particles are common in obesity and cardiovascular disease (CVD). Increases in large HDL particles are favourably associated with reduced CVD event risk and coronary plaque burden. The objective of the study is to compare the effectiveness of low-carbohydrate diets and weight loss for increasing blood levels of large HDL particles at 1 year. This study was performed by screening for body mass index (BMI) and metabolic syndrome in 160 consecutive subjects referred to our out-patient Metabolic Unit in South Italy. We administered dietary advice to four small groups rather than individually. A single team comprised of a dietitian and physician administered diet-specific advice to each group. Large HDL particles at baseline and 1 year were measured using two-dimensional gel electrophoresis. Dietary intake was assessed via 3-day diet records. Although 1-year weight loss did not differ between diet groups (mean 4.4 %), increases in large HDL particles paralleled the degree of carbohydrate restriction across the four diets (p<0.001 for trend). Regression analysis indicated that magnitude of carbohydrate restriction (percentage of calories as carbohydrate at 1 year) and weight loss were each independent predictors of 1-year increases in large HDL concentration. Changes in HDL cholesterol concentration were modestly correlated with changes in large HDL particle concentration (r=0.47, p=.001). In conclusion, reduction of excess dietary carbohydrate and body weight improved large HDL levels. Comparison trials with cardiovascular outcomes are needed to more fully evaluate these findings. PMID:27103896

  4. Metabolic determinants of body weight after cats were fed a low-carbohydrate high-protein diet or a high-carbohydrate low-protein diet ad libitum for 8 wk.

    PubMed

    Coradini, M; Rand, J S; Morton, J M; Rawlings, J M

    2014-10-01

    Overweight and obese conditions are common in cats and are associated with the development of a number of diseases. Knowledge of metabolic determinants and predictors of weight gain may enable better preventative strategies for obesity in cats. Lean, healthy cats were fed either a low-carbohydrate high-protein diet (n 16) or a high-carbohydrate low-protein (n 16) diet ad libitum for 8 wk. Potential determinants and predictors of final body weight assessed were body fat and lean masses, energy required for maintenance, energy requirements above maintenance for each kilogram of weight gain, insulin sensitivity index, fasting, mean 24-h and peak plasma glucose, insulin, and leptin concentrations, and fasting and mean 24-h serum adiponectin concentrations. In cats fed the low-carbohydrate high-protein diet, after adjusting for initial body weight, those with higher energy requirements for weight gain and higher fasting glucose concentration had higher final body weights (P ≤ 0.01). Predicted final body weights using initial body weight, fasting glucose and mean 24-h insulin concentrations (partial R(2) 37.3%) were imprecise. An equation using just initial body weight and fasting glucose concentration would be of more practical value, but was marginally less precise. In cats fed the high-carbohydrate low-protein diet, those with lower fasting leptin concentration initially had higher final body weights (P = 0.01). Predicted final body weights using initial body weight, energy requirements for maintenance, total body fat percentage and fasting leptin concentration (partial R(2) 39.2%) were reasonably precise. Further studies are warranted to confirm these findings and to improve the precision of predicted final body weights.

  5. Aspects of lipid and carbohydrate metabolism, dietary biotin and fatty liver and kidney syndrome in broilers.

    PubMed

    Balnave, D; Pearce, J

    1976-11-01

    Two experiments were performed to investigate the biochemical changes associated with FLKS. A diet reported to induce FLKS was fed with or without supplementary biotin to broilers. In experiment 1 various stresses were applied to the birds. 2. In experiment 1 mortality from FLKS was 6% and in experiment 2 nil. Stress had little effect on the induction of the syndrome. 3. There were no significant differences due to diet in any of the variables examined in apparently normal birds. 4. Birds affected by FLKS showed the typical changes of increased liver and kidney weights and lipid contents but hepatic enzyme activities did not differ significantly from those of normal birds except that malate dehydrogenase (decarboxylating) (NADP) activity was significantly decreased. 5. Despite the low content of biotin in the unsupplemented diet (57 mug/kg) liver biotin content was not low in birds fed on this diet. 6. The results suggest that the incidence of FLKS is not related solely to dietary biotin content.

  6. [Comparative evaluation of the influence of calcium channel blockers of derivatives of 1,4-dihydropyridine--amlodipine and dimeodipine--on parameters of carbohydrate metabolism in the blood of rats with doxorubicin-induced cardiomyopathy].

    PubMed

    Sachok, V V; Mokhort, M A

    2014-01-01

    Presented are experimental data on the influence of calcium antagonists of the third-generation derivatives of 1,4-dihydropyridines--amlodipine (1.5 mg/kg), dimeodipine (1.5 mg/kg)--on parameters of carbohydrate metabolism in rat blood model doxorubicin-induced cardiomyopathy. The possibility for correcting carbohydrate metabolic disorders in the blood with the above drugs through a reduction of lactate, lactate/pyruvic retio, LDH activity, normalization of the level of glycogen, glucose, pyruvate.

  7. Patterns of organic acids exuded by pioneering fungi from a glacier forefield are affected by carbohydrate sources

    NASA Astrophysics Data System (ADS)

    Brunner, Ivano; Goren, Asena; Schlumpf, Alessandro

    2014-01-01

    Bare soils in the area of retreating glaciers are ideal environments to study the role of microorganisms in the early soil formation and in processes of mineral weathering. The aim of our study was to investigate whether the source of carbohydrate would influence the patterns of organic acids exuded by fungal species. Three pioneering fungus species, isolated from fine granitic sediments in front of the Damma glacier from the central Swiss Alps, have previously been found to have the capability to exude organic acids and dissolve granite powder. In batch experiments, various carbohydrates, including glucose, cellulose, pectin, pollen, and cell remnants of cyanobacteria, fungi, and algae, were applied as carbohydrate sources and the patterns of exuded organic acids recorded. The results showed that two fungi, the zygomycete fungus Mucor hiemalis and the ascomycete fungus Penicillium chrysogenum, released a significantly higher amount of organic acids in dependence on specific carbohydrate sources. Pollen and algae as carbohydrate sources triggered significantly the exudation of malate in M. hiemalis, and pollen and cellulose that of oxalate in P. chrysogenum. We conclude that the occurrence of complex carbohydrate sources in nutrient-deficient deglaciated soils may positively influence the exudation of organic acids of fungi. In particular, pollen and remnants of other microorganisms can trigger the exudation of organic acids of fungi in order to promote the weathering of minerals and to make nutrients available that would otherwise be trapped in that cryospheric environment.

  8. Multiple dietary supplements do not affect metabolic and cardiovascular health

    PubMed Central

    Holloszy, John O.; Fontana, Luigi

    2014-01-01

    Dietary supplements are widely used for health purposes. However, little is known about the metabolic and cardiovascular effects of combinations of popular over-the-counter supplements, each of which has been shown to have anti-oxidant, anti-inflammatory and pro-longevity properties in cell culture or animal studies. This study was a 6-month randomized, single-blind controlled trial, in which 56 non-obese (BMI 21.0-29.9 kg/m2) men and women, aged 38 to 55 yr, were assigned to a dietary supplement (SUP) group or control (CON) group, with a 6-month follow-up. The SUP group took 10 dietary supplements each day (100 mg of resveratrol, a complex of 800 mg each of green, black, and white tea extract, 250 mg of pomegranate extract, 650 mg of quercetin, 500 mg of acetyl-l-carnitine, 600 mg of lipoic acid, 900 mg of curcumin, 1 g of sesamin, 1.7 g of cinnamon bark extract, and 1.0 g fish oil). Both the SUP and CON groups took a daily multivitamin/mineral supplement. The main outcome measures were arterial stiffness, endothelial function, biomarkers of inflammation and oxidative stress, and cardiometabolic risk factors. Twenty-four weeks of daily supplementation with 10 dietary supplements did not affect arterial stiffness or endothelial function in nonobese individuals. These compounds also did not alter body fat measured by DEXA, blood pressure, plasma lipids, glucose, insulin, IGF-1, and markers of inflammation and oxidative stress. In summary, supplementation with a combination of popular dietary supplements has no cardiovascular or metabolic effects in non-obese relatively healthy individuals. PMID:24659610

  9. Effects of recombinant human growth hormone on hepatic lipid and carbohydrate metabolism in HIV-infected patients with fat accumulation.

    PubMed

    Schwarz, Jean-Marc; Mulligan, Kathleen; Lee, Jeongae; Lo, Joan C; Wen, Michael; Noor, Mustafa A; Grunfeld, Carl; Schambelan, Morris

    2002-02-01

    We recently reported that treatment with a pharmacologic dose of recombinant human growth hormone (GH) resulted in a significant loss of body fat and gain in lean tissue in HIV-infected patients with syndromes of fat accumulation. However, insulin-mediated glucose disposal decreased transiently after one month of GH therapy. The present paper focuses on the changes of hepatic carbohydrate and fat metabolism associated with GH treatment in the same subjects. We assessed hepatic insulin sensitivity under both fasting and hyperinsulinemic-euglycemic clamp conditions prior to and after one and six months of GH treatment (3 mg/day) in five patients using stable isotope tracer techniques. Indirect calorimetry, and measurements of lipid concentrations. Fasting endogenous glucose production (EGP) increased significantly at one month (12.0 +/- 0.7 to 14.9 +/- 0.9 micromol/kg/min, P < 0.03), and the increase was sustained at six months of GH treatment (14.0 +/- 1.1 micromol/kg/min, NS). This increase in EGP was driven in part by increased glucogenesis (GNG) (3.5 +/- 0.9 to 5.2 +/- 0.9 and 5.8 +/-1.2 micromol/kg/min, n = 4, P < 0.01 and P < 0.01 at one and six months, respectively); small changes in hepatic glycogenolysis also contributed. Sustained increases in lipolysis and progressive decreases in hepatic fractional de novo lipogenesis (DNL) and triglyceride concentrations occurred with GH treatment. These changes were accompanied by an improved lipid profile with a significant increase in HDL cholesterol and significant decreases in total and LDL cholesterol and triglyceride levels, the latter consistent with the decrease in hepatic DNL. During a hyperinsulinemic-euglycemic glucose clamp, EGP and GNG were markedly suppressed compared to the corresponding time points under fasting conditions, albeit less so when measured after one month of GH treatment. Thus, in HIV-infected patients with abnormal fat distribution, pharmacologic doses of GH improved the overall lipid

  10. Arabinoxylan‐oligosaccharides (AXOS) affect the protein/carbohydrate fermentation balance and microbial population dynamics of the Simulator of Human Intestinal Microbial Ecosystem

    PubMed Central

    Sanchez, J. I.; Marzorati, M.; Grootaert, C.; Baran, M.; Van Craeyveld, V.; Courtin, C. M.; Broekaert, W. F.; Delcour, J. A.; Verstraete, W.; Van de Wiele, T.

    2009-01-01

    Summary Arabinoxylan‐oligosaccharides (AXOS) are a recently newly discovered class of candidate prebiotics as – depending on their structure – they are fermented in different regions of gastrointestinal tract. This can have an impact on the protein/carbohydrate fermentation balance in the large intestine and, thus, affect the generation of potentially toxic metabolites in the colon originating from proteolytic activity. In this study, we screened different AXOS preparations for their impact on the in vitro intestinal fermentation activity and microbial community structure. Short‐term fermentation experiments with AXOS with an average degree of polymerization (avDP) of 29 allowed part of the oligosaccharides to reach the distal colon, and decreased the concentration of proteolytic markers, whereas AXOS with lower avDP were primarily fermented in the proximal colon. Additionally, prolonged supplementation of AXOS with avDP 29 to the Simulator of Human Intestinal Microbial Ecosystem (SHIME) reactor decreased levels of the toxic proteolytic markers phenol and p‐cresol in the two distal colon compartments and increased concentrations of beneficial short‐chain fatty acids (SCFA) in all colon vessels (25–48%). Denaturant gradient gel electrophoresis (DGGE) analysis indicated that AXOS supplementation only slightly modified the total microbial community, implying that the observed effects on fermentation markers are mainly caused by changes in fermentation activity. Finally, specific quantitative PCR (qPCR) analysis showed that AXOS supplementation significantly increased the amount of health‐promoting lactobacilli as well as of Bacteroides–Prevotella and Clostridium coccoides–Eubacterium rectale groups. These data allow concluding that AXOS are promising candidates to modulate the microbial metabolism in the distal colon. PMID:21261885

  11. iTRAQ Protein Profile Differential Analysis of Dormant and Germinated Grassbur Twin Seeds Reveals that Ribosomal Synthesis and Carbohydrate Metabolism Promote Germination Possibly Through the PI3K Pathway.

    PubMed

    Zhang, Guo-Liang; Zhu, Yue; Fu, Wei-Dong; Wang, Peng; Zhang, Rui-Hai; Zhang, Yan-Lei; Song, Zhen; Xia, Gui-Xian; Wu, Jia-He

    2016-06-01

    Grassbur is a destructive and invasive weed in pastures, and its burs can cause gastric damage to animals. The strong adaptability and reproductive potential of grassbur are partly due to a unique germination mechanism whereby twin seeds develop in a single bur: one seed germinates, but the other remains dormant. To investigate the molecular mechanism of seed germination in twin seeds, we used isobaric tags for relative and absolute quantitation (iTRAQ) to perform a dynamic proteomic analysis of germination and dormancy. A total of 1,984 proteins were identified, 161 of which were considered to be differentially accumulated. The differentially accumulated proteins comprised 102 up-regulated and 59 down-regulated proteins. These proteins were grouped into seven functional categories, ribosomal proteins being the predominant group. The authenticity and accuracy of the results were confirmed by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time reverse transcription-PCR (qPCR). A dynamic proteomic analysis revealed that ribosome synthesis and carbohydrate metabolism affect seed germination possibly through the phosphoinositide 3-kinase (PI3K) pathway. As the PI3K pathway is generally activated by insulin, analyses of seeds treated with exogenous insulin by qPCR, ELISA and iTRAQ confirmed that the PI3K pathway can be activated, which suppresses dormancy and promotes germination in twin grassbur seeds. Together, these results show that the PI3K pathway may play roles in stimulating seed germination in grassbur by modulating ribosomal synthesis and carbohydrate metabolism.

  12. Co-Ingestion of Whey Protein with a Carbohydrate-Rich Breakfast Does Not Affect Glycemia, Insulinemia or Subjective Appetite Following a Subsequent Meal in Healthy Males

    PubMed Central

    Allerton, Dean M.; Campbell, Matthew D.; Gonzalez, Javier T.; Rumbold, Penny L. S.; West, Daniel J.; Stevenson, Emma J.

    2016-01-01

    We aimed to assess postprandial metabolic and appetite responses to a mixed-macronutrient lunch following prior addition of whey protein to a carbohydrate-rich breakfast. Ten healthy males (age: 24 ± 1 years; body mass index (BMI): 24.5 ± 0.7 kg/m2) completed three trials in a non-isocaloric, crossover design. A carbohydrate-rich breakfast (93 g carbohydrate; 1799 kJ) was consumed with (CHO + WP) or without (CHO) 20 g whey protein isolate (373 kJ), or breakfast was omitted (NB). At 180 min, participants consumed a mixed-macronutrient lunch meal. Venous blood was sampled at 15 min intervals following each meal and every 30 min thereafter, while subjective appetite sensations were collected every 30 min throughout. Post-breakfast insulinemia was greater after CHO + WP (time-averaged area under the curve (AUC0–180 min): 193.1 ± 26.3 pmol/L), compared to CHO (154.7 ± 18.5 pmol/L) and NB (46.1 ± 8.0 pmol/L; p < 0.05), with no difference in post-breakfast (0–180 min) glycemia (CHO + WP, 3.8 ± 0.2 mmol/L; CHO, 4.2 ± 0.2 mmol/L; NB, 4.2 ± 0.1 mmol/L; p = 0.247). There were no post-lunch (0–180 min) effects of condition on glycemia (p = 0.492), insulinemia (p = 0.338) or subjective appetite (p > 0.05). Adding whey protein to a carbohydrate-rich breakfast enhanced the acute postprandial insulin response, without influencing metabolic or appetite responses following a subsequent mixed-macronutrient meal. PMID:26927166

  13. Slow-release carbohydrates: growing evidence on metabolic responses and public health interest. Summary of the symposium held at the 12th European Nutrition Conference (FENS 2015)

    PubMed Central

    Vinoy, Sophie; Laville, Martine; Feskens, Edith J M

    2016-01-01

    To draw attention to the necessity of considering differences in the digestibility of carbohydrates, and more specifically of starch, a symposium was held at the 12th European Nutrition Conference (FENS), which took place in Berlin from October 20 to 23, 2015. The purpose of this session was to present the consolidated knowledge and recent advances regarding the relationship between slow-release carbohydrates, metabolic responses, and public health issues. Three main topics were presented: 1) the definition of, sources of, and recognised interest in the glycaemic response to slowly digestible starch (SDS); 2) clinical evidence regarding the physiological effects of slow-release carbohydrates from cereal foods; and 3) interest in reducing the postprandial glycaemic response to help prevent metabolic diseases. Foods with the highest SDS content induce the lowest glycaemic responses, as the starch is protected from gelatinisation during processing. In humans, high-SDS food consumption induces slower glucose release, lower postprandial insulinaemia, and stimulation of gut hormones. Moreover, postprandial hyperglycaemia is an independent risk factor for type two diabetes mellitus (T2DM) and cardiovascular disease (CVD). Therefore, given the plausible aetiologic mechanisms, we argue that postprandial glucose levels are relevant for health and disease and represent a meaningful target for intervention, for example, through dietary factors. This symposium was organised by Mondelez International R&D. PMID:27388153

  14. Metabolic context affects hemodynamic response to bupivacaine in the isolated rat heart.

    PubMed

    Edelman, Lucas B; Ripper, Richard; Kelly, Kemba; Di Gregorio, Guido; Weinberg, Guy L

    2008-03-10

    Previous studies have demonstrated that the local anesthetic bupivacaine selectively inhibits oxidative metabolism of fatty acids in isolated cardiac mitochondria. In the present investigation, we compare the development of bupivacaine cardiotoxicity during fatty acid and carbohydrate metabolism. Hearts from adult male Sprague-Dawley rats were excised and retrograde perfused with a solution containing fatty acid (oleate or octanoate) or carbohydrate substrates for cardiac metabolism. An infusion of bupivacaine was initiated and sustained until asystole, after which full cardiac recovery was allowed. During fatty acid metabolism, substantially lower bupivacaine doses induced both arrhythmia (60.4+/-11.5 microg oleate and 106.8+/-14.8 octanoate versus 153.4+/-21.4 carbohydrate; P<0.05) and asystole (121.0+/-30.1 microg and 171.5+/-20.2 versus 344.7+/-34.6; P<0.001). Dose-response analysis revealed significantly increased sensitivity to bupivacaine toxicity during fatty acid metabolism, indicated by lower V50 doses for both heart rate (70.6+/-5.6 microg oleate and 122.3+/-6.2 octanoate versus 152.6+/-8.6) and rate-pressure product (63.4+/-5.1 microg and 133.7+/-7.9 versus 165.1+/-12.2). Time to recovery following bupivacaine exposure was elevated in the fatty acid group (24.3+/-2.0 s versus 15.8+/-3.1; P<0.04). Fatty acid metabolism was shown to predispose the isolated heart to bupivacaine toxicity, confirming that the local anesthetic exerts specific effects on lipid processes in cardiomyocytes.

  15. Varying type of forage, concentration of metabolizable protein, and source of carbohydrate affects nutrient digestibility and production by dairy cows.

    PubMed

    Weiss, W P; St-Pierre, N R; Willett, L B

    2009-11-01

    The effects of forage source, concentration of metabolizable protein (MP), type of carbohydrate, and their interactions on nutrient digestibility and production were evaluated using a central composite treatment design. All diets (dry basis) contained 50% forage that ranged from 25:75 to 75:25 alfalfa silage:corn silage. Rumen-degradable protein comprised 10.7% of the dry matter (DM) in all diets, but undegradable protein ranged from 4.1 to 7.1%, resulting in dietary MP concentrations of 8.8 to 12.0% of the DM. Dietary starch ranged from 22 to 30% of the DM with a concomitant decrease in neutral detergent fiber concentrations. A total of 15 diets were fed to 36 Holstein cows grouped in 6 blocks. Each block consisted of three 21-d periods, and each cow was assigned a unique sequence of 3 diets, resulting in 108 observations. Milk production and composition, feed intake, and digestibility of major nutrients (via total collection of feces and urine) were measured. Few significant interactions between main effects were observed. Starch concentration had only minor effects on digestibility and production. Replacing corn silage with alfalfa decreased digestibility of N but increased digestibility of neutral detergent fiber. Increasing the concentration of MP increased N digestibility. The concentration (Mcal/kg) of dietary digestible energy (DE) increased linearly as starch concentration increased (very small effect) and was affected by a forage by MP interaction. At low MP, high alfalfa reduced DE concentration, but at high MP, increasing alfalfa increased DE concentration. Increasing alfalfa increased DM and DE intakes, which increased yields of energy-corrected milk, protein, and fat. Increasing MP increased yields of energy-corrected milk and protein. The response in milk protein to changes in MP was much less than predicted using the National Research Council (2001) model.

  16. Adjuvant diet to improve hormonal and metabolic factors affecting breast cancer prognosis.

    PubMed

    Berrino, Franco; Villarini, Anna; De Petris, Michela; Raimondi, Milena; Pasanisi, Patrizia

    2006-11-01

    Western lifestyle, characterized by reduced physical activity and a diet rich in fat, refined carbohydrates, and animal protein is associated with high prevalence of overweight, metabolic syndrome, insulin resistance, and high plasma levels of several growth factors and sex hormones. Most of these factors are associated with breast cancer risk and, in breast cancer patients, with increased risk of recurrences. Recent trials have proven that such a metabolic and endocrine imbalance can be favorably modified through comprehensive dietary modification, shifting from Western to Mediterranean and macrobiotic diet.

  17. Effects of combined oral contraceptive ethinylestradiol (30 microg) and dienogest (2 mg) on carbohydrate metabolism during 1 year of conventional or extended-cycle use.

    PubMed

    Wiegratz, I; Stahlberg, S; Manthey, T; Sänger, N; Mittmann, K; Palombo-Kinne, E; Mellinger, U; Lange, E; Kuhl, H

    2010-05-01

    The effects of extended regimens of combined oral contraceptives (COCs) on carbohydrate metabolism are largely unknown. The present study compared the effects of a COC containing 30 microg ethinylestradiol and 2 mg dienogest (EE/DNG) in conventional and extended-cycle regimen over 1 year. Parameters of carbohydrate metabolism were measured in 59 women treated with EE/DNG either conventionally (13 cycles of 21+7 days) or in extended-cycle regimen (4 cycles of 84+7 days). Blood samples were taken in a control cycle, and at 3 and 12 months of treatment. The mean levels of HbA1c and fasting glucose levels remained stable in both conventional and extended-regimen of EE/DNG. The mean levels of fasting insulin and C-peptide underwent comparable increases in both regimens, suggesting a similar readjustment of glucose metabolism via slightly increased insulin secretion. For both regimens, the response to the oral glucose tolerance test (OGTT) showed a slightly impaired glucose tolerance and insulin resistance at 3 months. These changes improved or returned to baseline at 12 months. Accordingly, the mean index for insulin resistance (homeostasis model assessment of insulin resistance, HOMA-IR) increased and the mean insulin sensitivity index [ISI (composite)] decreased modestly in both groups. The present study demonstrates that there are no statistically significant differences between the effects of conventional and extended-cycle treatment on carbohydrate metabolism over 1 year of treatment. In general, the effects of both regimens were moderate and mostly transient.

  18. Identity of the Growth-Limiting Nutrient Strongly Affects Storage Carbohydrate Accumulation in Anaerobic Chemostat Cultures of Saccharomyces cerevisiae▿ † ‡

    PubMed Central

    Hazelwood, Lucie A.; Walsh, Michael C.; Luttik, Marijke A. H.; Daran-Lapujade, Pascale; Pronk, Jack T.; Daran, Jean-Marc

    2009-01-01

    Accumulation of glycogen and trehalose in nutrient-limited cultures of Saccharomyces cerevisiae is negatively correlated with the specific growth rate. Additionally, glucose-excess conditions (i.e., growth limitation by nutrients other than glucose) are often implicated in high-level accumulation of these storage carbohydrates. The present study investigates how the identity of the growth-limiting nutrient affects accumulation of storage carbohydrates in cultures grown at a fixed specific growth rate. In anaerobic chemostat cultures (dilution rate, 0.10 h−1) of S. cerevisiae, the identity of the growth-limiting nutrient (glucose, ammonia, sulfate, phosphate, or zinc) strongly affected storage carbohydrate accumulation. The glycogen contents of the biomass from glucose- and ammonia-limited cultures were 10- to 14-fold higher than those of the biomass from cultures grown under the other three glucose-excess regimens. Trehalose levels were specifically higher under nitrogen-limited conditions. These results demonstrate that storage carbohydrate accumulation in nutrient-limited cultures of S. cerevisiae is not a generic response to excess glucose but instead is strongly dependent on the identity of the growth-limiting nutrient. While transcriptome analysis of wild-type and msn2Δ msn4Δ strains confirmed that transcriptional upregulation of glycogen and trehalose biosynthesis genes is mediated by Msn2p/Msn4p, transcriptional regulation could not quantitatively account for the drastic changes in storage carbohydrate accumulation. The results of assays of glycogen synthase and glycogen phosphorylase activities supported involvement of posttranscriptional regulation. Consistent with the high glycogen levels in ammonia-limited cultures, the ratio of glycogen synthase to glycogen phosphorylase in these cultures was up to eightfold higher than the ratio in the other glucose-excess cultures. PMID:19734328

  19. Carbohydrate supplementation affects blood granulocyte and monocyte trafficking but not function after 2.5 h or running.

    PubMed

    Nieman, D C; Fagoaga, O R; Butterworth, D E; Warren, B J; Utter, A; Davis, J M; Henson, D A; Nehlsen-Cannarella, S L

    1997-07-01

    This randomized, double-blind, placebo-controlled study was designed to determine the influence of carbohydrate supplementation on the granulocyte and monocyte response to 2.5 h of high-intensity running [76.7 +/- 0.4% of maximal oxygen consumption (VO2max)]. Thirty experienced marathon runners (VO2max 53.4 +/- 1.0 mL.kg-1.min-1, age 41.5 +/- 1.4 y) were randomly assigned to carbohydrate-supplement (n = 17) and placebo (n = 13) groups. Subjects rested for 10-15 min before a blood sample was taken at 0715, and then ingested 0.75 L carbohydrate beverage or placebo. At 0730 subjects began running at 75-80% of VO2max for 2.5 h, and drank 0.25 L carbohydrate or placebo fluid every 15 min. Immediately after the 2.5-h run (1000), another blood sample was taken, followed by 1.5-h, 3-h, and 6-h recovery samples. Carbohydrate supplementation had a significant effect compared with placebo on the pattern of change in plasma glucose and cortisol, and the blood concentration of neutrophils (F[14, 112] = 5.13, P = 0.001) and monocytes (F[14, 112] = 4.78, P = 0.001), but not on blood granulocyte and monocyte phagocytosis or oxidative burst activity after 2.5 h of intensive running.

  20. Soluble carbohydrate allocation to roots, photosynthetic rate of leaves, and nitrate assimilation as affected by nitrogen stress and irradiance

    NASA Technical Reports Server (NTRS)

    Henry, L. T.; Raper, C. D. Jr

    1991-01-01

    Upon resupply of exogenous nitrogen to nitrogen-stressed plants, uptake rate of nitrogen is enhanced relative to nonstressed plants. Absorption of nitrogen presumably is dependent on availability of carbohydrates in the roots. A buildup in soluble carbohydrates thus should occur in roots of nitrogen-stressed plants, and upon resupply of exogenous nitrogen the increased uptake rate should be accompanied by a rapid decline in carbohydrates to prestress levels. To evaluate this relationship, three sets of tobacco plants growing in a complete hydroponic solution containing 1.0 mM NO3- were either continued in the complete solution for 21 d, transferred to a minus-nitrogen solution for 21 d, or transferred to a minus-nitrogen solution for 8-9 d and then returned to the 1.0 mM NO3- solution. These nitrogen treatments were imposed upon plants growing at photosynthetic photon flux densities of 700 and 350 micromoles m-2 s-1. Soluble carbohydrate levels in roots increased during onset of nitrogen stress to levels that were fourfold greater than in roots of non-stressed plants. Following resupply of external nitrogen, a rapid resumption of nitrogen uptake was accompanied by a decline in soluble carbohydrates in roots to levels characteristic of nonstressed plants. This pattern of soluble carbohydrate levels in roots during onset of and recovery from nitrogen stress occurred at both irradiance levels. The response of net photosynthetic rate to nitrogen stress could be expressed as a nonlinear function of concentration of reduced nitrogen in leaves. The net photosynthetic rate at a given concentration of reduced nitrogen, however, averaged 10% less at the lower than at the higher irradiance. The decline in net photosynthetic rate per unit of reduced nitrogen in leaves at the lower irradiance was accompanied by an increase in the nitrate fraction of total nitrogen in leaves from 20% at the higher irradiance to 38% at the lower irradiance.

  1. Sodium-Glucose Cotransporter 2 Inhibitor and a Low Carbohydrate Diet Affect Gluconeogenesis and Glycogen Content Differently in the Kidney and the Liver of Non-Diabetic Mice

    PubMed Central

    Atageldiyeva, Kuralay; Fujita, Yukihiro; Yanagimachi, Tsuyoshi; Mizumoto, Katsutoshi; Takeda, Yasutaka; Honjo, Jun; Takiyama, Yumi; Abiko, Atsuko; Makino, Yuichi; Haneda, Masakazu

    2016-01-01

    A low carbohydrate diet (LCHD) as well as sodium glucose cotransporter 2 inhibitors (SGLT2i) may reduce glucose utilization and improve metabolic disorders. However, it is not clear how different or similar the effects of LCHD and SGLT2i are on metabolic parameters such as insulin sensitivity, fat accumulation, and especially gluconeogenesis in the kidney and the liver. We conducted an 8-week study using non-diabetic mice, which were fed ad-libitum with LCHD or a normal carbohydrate diet (NCHD) and treated with/without the SGLT-2 inhibitor, ipragliflozin. We compared metabolic parameters, gene expression for transcripts related to glucose and fat metabolism, and glycogen content in the kidney and the liver among the groups. SGLT2i but not LCHD improved glucose excursion after an oral glucose load compared to NCHD, although all groups presented comparable non-fasted glycemia. Both the LCHD and SGLT2i treatments increased calorie-intake, whereas only the LCHD increased body weight compared to the NCHD, epididimal fat mass and developed insulin resistance. Gene expression of certain gluconeogenic enzymes was simultaneously upregulated in the kidney of SGLT2i treated group, as well as in the liver of the LCHD treated group. The SGLT2i treated groups showed markedly lower glycogen content in the liver, but induced glycogen accumulation in the kidney. We conclude that LCHD induces deleterious metabolic changes in the non-diabetic mice. Our results suggest that SGLT2i induced gluconeogenesis mainly in the kidney, whereas for LCHD it was predominantly in the liver. PMID:27327650

  2. Temperature modulates hepatic carbohydrate metabolic enzyme activity and gene expression in juvenile GIFT tilapia (Oreochromis niloticus) fed a carbohydrate-enriched diet.

    PubMed

    Qiang, J; He, J; Yang, H; Wang, H; Kpundeh, M D; Xu, P; Zhu, Z X

    2014-02-01

    The effects of rearing temperature on hepatic glucokinase (GK), glucose-6-phosphatase (G6Pase) and Glucose-6-phosphate dehydrogenase (G6PD) activity and gene expression were studied in GIFT (genetically improved farmed tilapia) tilapia fed a high carbohydrate diet containing 28% crude protein, 5% crude lipid and 40% wheat starch. Triplicate groups of fish (11.28 g initial body weight) were fed the diet for 45 days at 22 °C, 28 °C or 34 °C. At the end of the trial, final body weight of juvenile at 28 °C (59.12 g) was higher than that of the fish reared at 22 °C (27.13 g) and 34 °C (43.17 g). Feed intake, feed efficiency and protein efficiency ratio were also better at 28 °C. Liver glycogen levels were higher at 28 °C, while plasma glucose levels were higher in the 22 °C group. Significant (P<0.05) effects of water temperature on enzymes activities and gene expression were observed. Hepatic GK activity and mRNA level were higher at 28 °C than at 34 °C. Higher G6Pase and G6PD activity and gene expression were observed at 22 °C. Overall, the data show that juveniles reared at 28 °C exhibited enhanced liver glycolytic capacity. In contrast, hepatic gluconeogenesis and lipogenesis were increased by low temperature (22 °C).

  3. Metabolic engineering for the production of shikimic acid in an evolved Escherichia coli strain lacking the phosphoenolpyruvate: carbohydrate phosphotransferase system

    PubMed Central

    2010-01-01

    Background Shikimic acid (SA) is utilized in the synthesis of oseltamivir-phosphate, an anti-influenza drug. In this work, metabolic engineering approaches were employed to produce SA in Escherichia coli strains derived from an evolved strain (PB12) lacking the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS-) but with capacity to grow on glucose. Derivatives of PB12 strain were constructed to determine the effects of inactivating aroK, aroL, pykF or pykA and the expression of plasmid-coded genes aroGfbr, tktA, aroB and aroE, on SA synthesis. Results Batch cultures were performed to evaluate the effects of genetic modifications on growth, glucose consumption, and aromatic intermediate production. All derivatives showed a two-phase growth behavior with initial high specific growth rate (μ) and specific glucose consumption rate (qs), but low level production of aromatic intermediates. During the second growth phase the μ decreased, whereas aromatic intermediate production reached its maximum. The double aroK- aroL- mutant expressing plasmid-coded genes (strain PB12.SA22) accumulated SA up to 7 g/L with a yield of SA on glucose of 0.29 mol/mol and a total aromatic compound yield (TACY) of 0.38 mol/mol. Single inactivation of pykF or pykA was performed in PB12.SA22 strain. Inactivation of pykF caused a decrease in μ, qs, SA production, and yield; whereas TACY increased by 33% (0.5 mol/mol). Conclusions The effect of increased availability of carbon metabolites, their channeling into the synthesis of aromatic intermediates, and disruption of the SA pathway on SA production was studied. Inactivation of both aroK and aroL, and transformation with plasmid-coded genes resulted in the accumulation of SA up to 7 g/L with a yield on glucose of 0.29 mol/mol PB12.SA22, which represents the highest reported yield. The pykF and pykA genes were inactivated in strain PB12.SA22 to increase the production of aromatic compounds in the PTS- background. Results

  4. Does iodine biofortification affect oxidative metabolism in lettuce plants?

    PubMed

    Blasco, Begoña; Ríos, Juan Jose; Leyva, Rocío; Cervilla, Luis Miguel; Sánchez-Rodríguez, Eva; Rubio-Wilhelmi, María Mar; Rosales, Miguel Angel; Ruiz, Juan Manuel; Romero, Luis

    2011-09-01

    Plants produce low levels of reactive oxygen species (ROS), which form part of basic cell chemical communication; however, different types of stress can lead to an overexpression of ROS that can damage macromolecules essential for plant growth and development. Iodine is vital to human health, and iodine biofortification programs help improve the human intake through plant consumption. This biofortification process has been shown to influence the antioxidant capacity of lettuce plants, suggesting that the oxidative metabolism of the plant may be affected. The results of this study demonstrate that the response to oxidative stress is variable and depends on the form of iodine applied. Application of iodide (I(-)) to lettuce plants produces a reduction in superoxide dismutase (SOD) activity and an increase in catalase (CAT) and L-galactono dehydrogenase enzyme activities and in the activity of antioxidant compounds such as ascorbate (AA) and glutathione. This did not prove a very effective approach since a dose of 80 μM produced a reduction in the biomass of the plants. For its part, application of iodate (IO (3) (-) ) produced an increase in the activities of SOD, ascorbate peroxidase, and CAT, the main enzymes involved in ROS detoxification; it also increased the concentration of AA and the regenerative activities of the Halliwell-Asada cycle. These data confirm the non-phytotoxicity of IO (3) (-) since there is no lipid peroxidation or biomass reduction. According to our results, the ability of IO (3) (-) to induce the antioxidant system indicates that application of this form of iodine may be an effective strategy to improve the response of plants to different types of stress.

  5. [Influence of bean yellow mosaic virus on metabolism of photosynthetic pigments, proteins and carbohydrates in Glycine soja L].

    PubMed

    Kyrychenko, A M

    2014-01-01

    This paper presents data on BYMV effects on some physiological processes of Glycine soja L. cultivated in the right-bank forest-steppe regions. Pigment content (chlorophyll a, b and carotenoids), soluble proteins and water soluble carbohydrates were estimated and, as has been shown, are subjected to significant changes as compared with control plants, namely: a decrease in the content of chlorophyll a, b and carotenoids was 64%, 53% and 36% compared with the control plants. The significant increase in carbohydrates (56% compared to the control) was observed at the end of the test period.

  6. Differences between the Bud End and Stem End of Potatoes in Dry Matter Content, Starch Granule Size, and Carbohydrate Metabolic Gene Expression at the Growing and Sprouting Stages.

    PubMed

    Liu, Bailin; Zhang, Guodong; Murphy, Agnes; De Koeyer, David; Tai, Helen; Bizimungu, Benoit; Si, Huaijun; Li, Xiu-Qing

    2016-02-10

    Potatoes usually have the tuber bud end dominance in growth during tuber bulking and in tuber sprouting, likely using carbohydrates from the tuber stem end. We hypothesized that the tuber bud end and tuber stem end coordination in carbohydrate metabolism gene expression is different between the bulking dominance and sprouting dominance of the tuber bud end. After comparing the growing tubers at harvest from a green vine and the stage that sprouts just started to emerge after storage of tubers at room temperature, we found the following: (1) Dry matter content was higher in the tuber stem end than the tuber bud end at both stages. (2) The starch granule size was larger in the tuber bud end than in the tuber stem end. (3) The tuber bud end had higher gene expression for starch synthesis but a lower gene expression of sucrose transporters than the tuber stem end during tuber growing. (4) The tuber stem end at the sprouting stage showed more active gene expression in both starch degradation and resynthesis, suggesting more active export of carbohydrates, than the tuber bud end. The results indicate that the starch accumulation mechanism in the tuber bud end was different between field growing and post-harvest sprouting tubers and that tubers already increased dry matter and average starch granule sizes in the tuber bud end prior to the rapid growth of sprouts.

  7. Sugar Allocation to Metabolic Pathways is Tightly Regulated and Affects the Virulence of Streptococcus mutans

    PubMed Central

    Kawada-Matsuo, Miki; Oogai, Yuichi; Komatsuzawa, Hitoshi

    2016-01-01

    Bacteria take up and metabolize sugar as a carbohydrate source for survival. Most bacteria can utilize many sugars, including glucose, sucrose, and galactose, as well as amino sugars, such as glucosamine and N-acetylglucosamine. After entering the cytoplasm, the sugars are mainly allocated to the glycolysis pathway (energy production) and to various bacterial component biosynthesis pathways, including the cell wall, nucleic acids and amino acids. Sugars are also utilized to produce several virulence factors, such as capsule and lipoteichoic acid. Glutamine-fructose-6-phosphate aminotransferase (GlmS) and glucosamine-6-phosphate deaminase (NagB) have crucial roles in sugar distribution to the glycolysis pathway and to cell wall biosynthesis. In Streptococcus mutans, a cariogenic pathogen, the expression levels of glmS and nagB are coordinately regulated in response to the presence or absence of amino sugars. In addition, the disruption of this regulation affects the virulence of S. mutans. The expression of nagB and glmS is regulated by NagR in S. mutans, but the precise mechanism underlying glmS regulation is not clear. In Staphylococcus aureus and Bacillus subtilis, the mRNA of glmS has ribozyme activity and undergoes self-degradation at the mRNA level. However, there is no ribozyme activity region on glmS mRNA in S. mutans. In this review article, we summarize the sugar distribution, particularly the coordinated regulation of GlmS and NagB expression, and its relationship with the virulence of S. mutans. PMID:28036052

  8. Carbohydrates and Depression.

    ERIC Educational Resources Information Center

    Wurtman, Richard J.; Wurtman, Judith J.

    1989-01-01

    Describes the symptoms, such as appetite change and mood fluctuation, basic mechanisms, and some treatments of Seasonal Affective Disorder (SAD), Carbohydrate-Craving Obesity (CCO) and Premenstrual Syndrome (PMS). Provides several tables and diagrams, and three reading references. (YP)

  9. Effect of salinity stress on growth and carbohydrate metabolism in three rice (Oryza sativa L.) cultivars differing in salinity tolerance.

    PubMed

    Pattanagul, Wattana; Thitisaksakul, Maysaya

    2008-10-01

    Rice seedlings cv. Khao Dawk Mali 105 (salt-sensitive), Luang Anan (moderately salt-tolerant) and Pokkali (salt-tolerant) were exposed to 0, 50, 100 and 150 mM NaCI for 9 d. Salinity stress caused reduction in leaf relative water contents in all cultivars. Shoot length of cv. Pokkali was least affected by salinity stress whereas increased root length in response to salinity stress was apparent in cvs. Khao Dawk Mali 105 and Luang Anan. Increased salinity level also caused reduction in fresh and dry weights in cvs. Khao Dawk Mali 105 and Luang Anan, but had no effect in cv. Pokkali except at 150 mM. Accumulation of total soluble sugars and sucrose in mature leaves were observed in cv. Khao Dawk Mali 105 exposed to high level of salinity whereas their concentrations in cvs. Luang Anan and Pokkali remained the same as control plants. Accumulation of sucrose in cv. Khao Dawk Mali 105 was suggested to be resulted from the alteration of photosynthate partitioning since the activities of sucrose phosphate synthase were not affected by salinity in this cultivar. On the contrary, salinity stress induced an accumulation of starch in cv. Pokkali. It is suggested that partitioning sugars into starch may involve in salinity tolerance by avoiding metabolic alterations.

  10. Ionizing Radiation Impairs T Cell Activation by Affecting Metabolic Reprogramming.

    PubMed

    Li, Heng-Hong; Wang, Yi-Wen; Chen, Renxiang; Zhou, Bin; Ashwell, Jonathan D; Fornace, Albert J

    2015-01-01

    Ionizing radiation has a variety of acute and long-lasting adverse effects on the immune system. Whereas measureable effects of radiation on immune cell cytotoxicity and population change have been well studied in human and animal models, little is known about the functional alterations of the surviving immune cells after ionizing radiation. The objective of this study was to delineate the effects of radiation on T cell function by studying the alterations of T cell receptor activation and metabolic changes in activated T cells isolated from previously irradiated animals. Using a global metabolomics profiling approach, for the first time we demonstrate that ionizing radiation impairs metabolic reprogramming of T cell activation, which leads to substantial decreases in the efficiency of key metabolic processes required for activation, such as glucose uptake, glycolysis, and energy metabolism. In-depth understanding of how radiation impacts T cell function highlighting modulation of metabolism during activation is not only a novel approach to investigate the pivotal processes in the shift of T cell homeostasis after radiation, it also may lead to new targets for therapeutic manipulation in the combination of radiotherapy and immune therapy. Given that appreciable effects were observed with as low as 10 cGy, our results also have implications for low dose environmental exposures.

  11. Effects of Second and Third Generation Oral Contraceptives on Lipid and Carbohydrate Metabolism in Overweight and Obese Women: A Randomized Triple-Blind Controlled Trial

    PubMed Central

    Shahnazi, Mahnaz; Farshbaf-Khalili, Azizeh; Pourzeinali-Beilankouh, Samira; Sadrimehr, Farnaz

    2016-01-01

    Background Combined oral contraceptives (COCs) have not been shown to have major effects on lipid and carbohydrate metabolism in normal-weight women. However, we have limited information about the effects on women at high risk for cardiovascular disease and diabetes due to being overweight and obese. Objectives To evaluate the effects of second and third generation contraceptive pills on lipid and carbohydrate metabolism in overweight and obese women. Patients and Methods This triple-blind controlled trial was performed on 137 healthy women aged 18 - 40 years with a body mass index of 25-34.9 (kg/m2) who were referred to health centers in Tabriz, Iran from 2014 to 2015. The women were randomly divided into groups who were to take 30 mcg ethinyl estradiol/150 mcg levonorgestrel (EE/LGN) (n = 69) or 30 mcg ethinyl estradiol/150 mcg desogestrel (EE/DSG) (n = 68) with an allocation ratio of 1: 1 for three cycles. As primary outcomes, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and fasting plasma glucose (FPG) were assessed; total cholesterol (TC), triglycerides (TG), and 2-hour plasma glucose in the 75-g oral glucose tolerance test (2-hour 75-g OGTT) were assessed as secondary outcomes. Results The differences in lipid and carbohydrate parameters were not significant between the two groups, except for HDL-C (Adjusted MD (CI95%) = 7.00 (2.98 to 11.02)). HDL-C decreased with EE/LGN (P = 0.016) and increased with EE/DSG (P = 0.004). LDL-C and TC increased in both groups, whereas TG increased only with EE/DSG (P < 0.05). Compared with the baseline, FPG levels did not differ significantly in both groups, but EE/DSG increased 2-hour 75-g OGTT (P = 0.010). Conclusions We observed no significant differences between the two groups in lipid and carbohydrate metabolism, except for HDL-C. Considering the importance of overweight and obese women’s health, studies with longer follow-up periods are recommended in this respect. PMID

  12. Caffeine and carbohydrate supplementation during exercise when in negative energy balance: effects on performance, metabolism, and salivary cortisol.

    PubMed

    Slivka, Dustin; Hailes, Walter; Cuddy, John; Ruby, Brent

    2008-12-01

    The ingestion of carbohydrate (+CHO) and caffeine (+CAF) during exercise is a commonly used ergogenic practice. Investigations are typically conducted with subjects who are in a rested state after an overnight fast. However, this state of positive energy balance is not achieved during many work and exercise circumstances. The aim of this study was to evaluate the substrate use and performance effects of caffeine and carbohydrate consumed alone and in combination while participants were in negative energy balance. Male participants (n = 9; 23 +/- 3 years; 74.1 +/- 10.6 kg) completed 4 trials in random order: -CAF/-CHO, -CAF/+CHO, +CAF/-CHO, and +CAF/+CHO. Diet and exercise were prescribed for 2 days before each trial to ensure negative energy balance. For each trial, before and after 2 h of cycling at 50% of maximal watts, a saliva sample and a muscle biopsy (vastus lateralis) were obtained. A simulated 20 km time trial was then performed. The respiratory exchange ratio was higher (p < 0.05) in +CHO trials and lower (p < 0.05) in the +CAF/+CHO trial than in the -CAF/+CHO trial. Salivary cortisol response was higher (p < 0.05) in the +CAF/-CHO trial than in any of the other trials. Muscle glycogen and heart rates were similar in all trials. Performance in the 20 km time trial was better in the -CAF/+CHO trial than in the -CAF/-CHO trial (p < 0.05), but the +CAF/+CHO trial was no better than the +CAF/-CHO trial (p > 0.05), or any of the other trials. When co-ingested with carbohydrate, caffeine increased fat use and decreased nonmuscle glycogen carbohydrate use over carbohydrate alone when participants are in negative energy balance; however, caffeine had no effect on the 20 km cycling time trial performance.

  13. Steam explosion of Brewer's spent grain improves enzymatic digestibility of carbohydrates and affects solubility and stability of proteins.

    PubMed

    Kemppainen, K; Rommi, K; Holopainen, U; Kruus, K

    2016-09-01

    Steam explosion was studied as a means to improve the enzymatic digestibility of carbohydrates in Brewer's spent grain, a protein and lipid-rich lignocellulosic by-product of the brewing industry. Having temperature, treatment time and the presence of acid catalyst as variables, a treatment at 200 °C for 10 min without an acid catalyst was found to be the most efficient, dissolving 12.1 % of the dry matter. Mainly oligomeric non-cellulosic glucan and arabinoxylan were dissolved, and the remaining insoluble carbohydrates could be efficiently hydrolysed by an enzyme cocktail (75 % hydrolysis yield). The process also caused partial protein degradation and dissolved over a third of the total nitrogen. Meanwhile, the insoluble protein appeared to become more strongly associated with acid-insoluble lignin. Compositional changes observed in the proteins and carbohydrates were supported by the results of epifluorescence microscopy. The process yielded three chemically different fractions which could serve as biorefinery products or intermediates.

  14. Revealing the molecular relationship between type 2 diabetes and the metabolic changes induced by a very-low-carbohydrate low-fat ketogenic diet

    PubMed Central

    2010-01-01

    Background The prevalence of type 2 diabetes is increasing worldwide, accounting for 85-95% of all diagnosed cases of diabetes. Clinical trials provide evidence of benefits of low-carbohydrate ketogenic diets in terms of clinical outcomes on type 2 diabetes patients. However, the molecular events responsible for these improvements still remain unclear in spite of the high amount of knowledge on the primary mechanisms of both the diabetes and the metabolic state of ketosis. Molecular network analysis of conditions, diseases and treatments might provide new insights and help build a better understanding of clinical, metabolic and molecular relationships among physiological conditions. Accordingly, our aim is to reveal such a relationship between a ketogenic diet and type 2 diabetes through systems biology approaches. Methods Our systemic approach is based on the creation and analyses of the cell networks representing the metabolic state in a very-low-carbohydrate low-fat ketogenic diet. This global view might help identify unnoticed relationships often overlooked in molecule or process-centered studies. Results A strong relationship between the insulin resistance pathway and the ketosis main pathway was identified, providing a possible explanation for the improvement observed in clinical trials. Moreover, the map analyses permit the formulation of some hypothesis on functional relationships between the molecules involved in type 2 diabetes and induced ketosis, suggesting, for instance, a direct implication of glucose transporters or inflammatory processes. The molecular network analysis performed in the ketogenic-diet map, from the diabetes perspective, has provided insights on the potential mechanism of action, but also has opened new possibilities to study the applications of the ketogenic diet in other situations such as CNS or other metabolic dysfunctions. PMID:21143928

  15. Protective Effect of Free and Bound Polyphenol Extracts from Ginger (Zingiber officinale Roscoe) on the Hepatic Antioxidant and Some Carbohydrate Metabolizing Enzymes of Streptozotocin-Induced Diabetic Rats.

    PubMed

    Kazeem, Mutiu Idowu; Akanji, Musbau Adewunmi; Yakubu, Musa Toyin; Ashafa, Anofi Omotayo Tom

    2013-01-01

    This study investigated the hepatoprotective effects of polyphenols from Zingiber officinale on streptozotocin-induced diabetic rats by assessing liver antioxidant enzymes, carbohydrate-metabolizing enzymes and liver function indices. Initial oral glucose tolerance test was conducted using 125 mg/kg, 250 mg/kg, and 500 mg/kg body weight of both free and bound polyphenols from Z. officinale. 28 day daily oral administration of 500 mg/kg body weight of free and bound polyphenols from Z. officinale to streptozotocin-induced (50 mg/kg) diabetic rats significantly reduced (P < 0.05) the fasting blood glucose compared to control groups. There was significant increase (P < 0.05) in the antioxidant enzymes activities in the animals treated with both polyphenols. Similarly, the polyphenols normalised the activities of some carbohydrate metabolic enzymes (hexokinase and phosphofructokinase) in the liver of the rats treated with it and significantly reduced (P < 0.05) the activities of liver function enzymes. The results from the present study have shown that both free and bound polyphenols from Z. officinale especially the free polyphenol could ameliorate liver disorders caused by diabetes mellitus in rats. This further validates the use of this species as medicinal herb and spice by the larger population of Nigerians.

  16. Proteomics of Fusarium oxysporum race 1 and race 4 reveals enzymes involved in carbohydrate metabolism and ion transport that might play important roles in banana Fusarium wilt.

    PubMed

    Sun, Yong; Yi, Xiaoping; Peng, Ming; Zeng, Huicai; Wang, Dan; Li, Bo; Tong, Zheng; Chang, Lili; Jin, Xiang; Wang, Xuchu

    2014-01-01

    Banana Fusarium wilt is a soil-spread fungal disease caused by Fusarium oxysporum. In China, the main virulence fungi in banana are F. oxysporum race 1 (F1, weak virulence) and race 4 (F4, strong virulence). To date, no proteomic analyses have compared the two races, but the difference in virulence between F1 and F4 might result from their differentially expressed proteins. Here we report the first comparative proteomics of F1 and F4 cultured under various conditions, and finally identify 99 protein species, which represent 59 unique proteins. These proteins are mainly involved in carbohydrate metabolism, post-translational modification, energy production, and inorganic ion transport. Bioinformatics analysis indicated that among the 46 proteins identified from F4 were several enzymes that might be important for virulence. Reverse transcription PCR analysis of the genes for 15 of the 56 proteins revealed that their transcriptional patterns were similar to their protein expression patterns. Taken together, these data suggest that proteins involved in carbohydrate metabolism and ion transport may be important in the pathogenesis of banana Fusarium wilt. Some enzymes such as catalase-peroxidase, galactosidase and chitinase might contribute to the strong virulence of F4. Overexpression or knockout of the genes for the F4-specific proteins will help us to further understand the molecular mechanism of Fusarium-induced banana wilt.

  17. Bacillus cereus ATCC 14579 RpoN (Sigma 54) Is a Pleiotropic Regulator of Growth, Carbohydrate Metabolism, Motility, Biofilm Formation and Toxin Production.

    PubMed

    Hayrapetyan, Hasmik; Tempelaars, Marcel; Nierop Groot, Masja; Abee, Tjakko

    2015-01-01

    Sigma 54 is a transcriptional regulator predicted to play a role in physical interaction of bacteria with their environment, including virulence and biofilm formation. In order to study the role of Sigma 54 in Bacillus cereus, a comparative transcriptome and phenotypic study was performed using B. cereus ATCC 14579 WT, a markerless rpoN deletion mutant, and its complemented strain. The mutant was impaired in many different cellular functions including low temperature and anaerobic growth, carbohydrate metabolism, sporulation and toxin production. Additionally, the mutant showed lack of motility and biofilm formation at air-liquid interphase, and this correlated with absence of flagella, as flagella staining showed only WT and complemented strain to be highly flagellated. Comparative transcriptome analysis of cells harvested at selected time points during growth in aerated and static conditions in BHI revealed large differences in gene expression associated with loss of phenotypes, including significant down regulation of genes in the mutant encoding enzymes involved in degradation of branched chain amino acids, carbohydrate transport and metabolism, flagella synthesis and virulence factors. Our study provides evidence for a pleiotropic role of Sigma 54 in B. cereus supporting its adaptive response and survival in a range of conditions and environments.

  18. Influence of gamma radiation on the activities of some carbohydrate metabolic enzymes in the cotyledons and the leaves of fenugreek (Trigonella foenum-graecum L. ) bean seedlings

    SciTech Connect

    Ahanotu, P.A.

    1985-01-01

    Studies indicated that 21-day old cotyledons from gamma irradiated seeds of fenugreek beans were heavier and had more starch and sugar than their non-irradiated controls. To test whether these effects occurred in the leaves and to seek a possible biochemical explanation for these results, the activities of five enzymes involved in carbohydrate metabolism were studied. Three groups of fenugreek bean seeds were irradiated (100-300 Gy) and then allowed to grow for 21 days. On harvest, wet and dry weights of both cotyledons and leaves were determined. Starch and sugar contents in cotyledons and leaves were measured. The five enzymes ..cap alpha..-amylase, ..beta..-amylase, starch phosphorylase, ADPG-pyrophosphorylase and ribulose-1,5-diphosphate carboxylase were extracted from cotyledons and leaves, respectively. The protein contents and activities of the enzyme extracts were determined. The results suggest an increase in carbohydrate metabolism in cotyldeons and a decrease in leaves due to the radiation treatment of the seeds before germination. Thus, increased amounts of starch and sugars are observed in the cotyledons, and decreased amounts in the leaves. Radiation damage to the translocatory system of the plant may retard the movement of sugars from the cotyledons to the other parts of the plant. This may cause accumulation of sugars and starch in the cotyledons, leading to an increase in their size and weight.

  19. Natural toxins that affect plant amino acid metabolism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A diverse range of natural compounds interfere with the synthesis and other aspects of amino acid metabolism. Some are amino acid analogues, but most are not. This review covers a number of specific natural phytotoxic compounds by molecular target site. Inhibition of glutamine synthetase is of part...

  20. Metabolic and transcriptional response of central metabolism affected by root endophytic fungus Piriformospora indica under salinity in barley.

    PubMed

    Ghaffari, Mohammad Reza; Ghabooli, Mehdi; Khatabi, Behnam; Hajirezaei, Mohammad Reza; Schweizer, Patrick; Salekdeh, Ghasem Hosseini

    2016-04-01

    The root endophytic fungus Piriformospora indica enhances plant adaptation to environmental stress based on general and non-specific plant species mechanisms. In the present study, we integrated the ionomics, metabolomics, and transcriptomics data to identify the genes and metabolic regulatory networks conferring salt tolerance in P. indica-colonized barley plants. To this end, leaf samples were harvested at control (0 mM NaCl) and severe salt stress (300 mM NaCl) in P. indica-colonized and non-inoculated barley plants 4 weeks after fungal inoculation. The metabolome analysis resulted in an identification of a signature containing 14 metabolites and ions conferring tolerance to salt stress. Gene expression analysis has led to the identification of 254 differentially expressed genes at 0 mM NaCl and 391 genes at 300 mM NaCl in P. indica-colonized compared to non-inoculated samples. The integration of metabolome and transcriptome analysis indicated that the major and minor carbohydrate metabolism, nitrogen metabolism, and ethylene biosynthesis pathway might play a role in systemic salt-tolerance in leaf tissue induced by the root-colonized fungus.

  1. Enumeration of human colonic bacteria producing phenolic and indolic compounds: effects of pH, carbohydrate availability and retention time on dissimilatory aromatic amino acid metabolism.

    PubMed

    Smith, E A; Macfarlane, G T

    1996-09-01

    Concentrations of phenolic compounds in human gut contents were more than fourfold higher in the distal colon (6.2 mmol kg-1) compared to the proximal bowel (1.4 mmol kg-1). Tryptophan metabolites were never found in more than trace amounts in large intestinal contents and phenol substituted fatty acids were the major products of aromatic amino acid fermentation that accumulated in the proximal colon, whereas phenol and p-cresol were more important in the distal gut, accounting for 70% of all products of dissimilatory aromatic amino acid metabolism. In vitro incubations of colonic material showed that phenol was produced most rapidly (1.0 mumol g-1 h-1), whereas indole was formed comparatively slowly (0.06 mumol g-1 h-1). Most probable number (MPN) estimations demonstrated that large populations of phenol and indole producing bacteria occur in the large intestine (range log10 9.8-11.5 (g dry wt faeces)-1, mean 10.6, N = 7). With respect to phenolic compounds, phenylacetate and phenylpropionate producers predominated, while indoleacetate-forming bacteria were the major tryptophan-utilizing organisms. Quantitation of products of dissimilatory aromatic amino acid metabolism in MPN tubes showed that phenol and phenylpropionate mainly accumulated at low sample dilutions, whereas phenylacetate, p-cresol, indoleacetate and indolepropionate were formed in greatest amounts at high sample dilutions. The significance of pH and carbohydrate availability with respect to aromatic amino acid metabolism was shown in batch culture fermentation studies, where net production of phenolic compounds by mixed populations of intestinal bacteria was reduced by approximately 33% during growth at pH 5.5 compared to pH 6.8, and by 60% in the presence of a fermentable carbohydrate. Experiments with 16 species of intestinal bacteria belonging to six different genera showed that environmental factors such as low pH and high carbohydrate availability markedly reduced dissimilatory aromatic amino

  2. Fusion and metabolism of plant cells as affected by microgravity.

    PubMed

    Hampp, R; Hoffmann, E; Schönherr, K; Johann, P; De Filippis, L

    1997-01-01

    Plant cell protoplasts derived from leaf tissue of two different tobacco species (Nicotiana tabacum., N. rustica L.) were exposed to short-term (sounding rocket experiments) and long-term (spacelab) microgravity environments in order to study both (electro) cell fusion and cell metabolism during early and later stages of tissue regeneration. The period of exposure to microgravity varied from 10 min (sounding rocket) to 10 d (space shuttle). The process of electro fusion of protoplasts was improved under conditions of microgravity: the time needed to establish close membrane contact between protoplasts (alignment time) was reduced (5 as compared to 15 s under 1 g) and numbers of fusion products between protoplasts of different specific density were increased by a factor of about 10. In addition, viability of fusion products, as shown by the ability to form callus, increased from about 60% to more than 90%. Regenerated fusion products obtained from both sounding-rocket and spacelab experiments showed a wide range of intermediate properties between the two parental plants. This was verified by isozyme analysis and random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). In order to address potential metabolic responses, more general markers such as the overall energy state (ATP/ADP ratio), the redox charge of the diphosphopyridine nucleotide system (NADH/NAD ratio), and the pool size of fructose-2,6-bisphosphate (Fru 2,6 bisp), a regulator of the balance between glycolysis and gluconeogenesis, were determined. Responses of these parameters were different with regard to short-term and long-term exposure. Shortly after transition to reduced gravitation (sounding rocket) ratios of ATP/ADP exhibited strong fluctuation while the pool size of NAD decreased (indicating an increased NADH/NAD ratio) and that of Fru 2,6 bisp increased. As similar changes can be observed under stress conditions, this response is probably indicative of a metabolic stress

  3. Carbohydrate-Free Peach (Prunus persica) and Plum (Prunus domestica) Juice Affects Fecal Microbial Ecology in an Obese Animal Model

    PubMed Central

    Markel, Melissa; Martino, Hercia S.; Minamoto, Yasushi; Steiner, Jörg M.; Byrne, David; Suchodolski, Jan S.; Mertens-Talcott, Susanne U.

    2014-01-01

    Background Growing evidence shows the potential of nutritional interventions to treat obesity but most investigations have utilized non-digestible carbohydrates only. Peach and plum contain high amounts of polyphenols, compounds with demonstrated anti-obesity effects. The underlying process of successfully treating obesity using polyphenols may involve an alteration of the intestinal microbiota. However, this phenomenon is not well understood. Methodology/Principal Findings Obese Zucker rats were assigned to three groups (peach, plum, and control, n = 10 each), wild-type group was named lean (n = 10). Carbohydrates in the fruit juices were eliminated using enzymatic hydrolysis. Fecal samples were obtained after 11 weeks of fruit or control juice administration. Real-time PCR and 454-pyrosequencing were used to evaluate changes in fecal microbiota. Over 1,500 different Operational Taxonomic Units at 97% similarity were detected in all rats. Several bacterial groups (e.g. Lactobacillus and members of Ruminococcacea) were found to be more abundant in the peach but especially in the plum group (plum juice contained 3 times more total polyphenolics compared to peach juice). Principal coordinate analysis based on Unifrac-based unweighted distance matrices revealed a distinct separation between the microbiota of control and treatment groups. These changes in fecal microbiota occurred simultaneously with differences in fecal short-chain acids concentrations between the control and treatment groups as well as a significant decrease in body weight in the plum group. Conclusions This study suggests that consumption of carbohydrate-free peach and plum juice has the potential to modify fecal microbial ecology in an obese animal model. The separate contribution of polyphenols and non-polyphenols compounds (vitamins and minerals) to the observed changes is unknown. PMID:25007331

  4. An enzymatic bridge between carbohydrate and amino acid metabolism: regulation of glutamate dehydrogenase by reversible phosphorylation in a severe hypoxia-tolerant crayfish.

    PubMed

    Dawson, Neal J; Storey, Kenneth B

    2012-04-01

    Glutamate dehydrogenase (GDH) (EC 1.4.1.3) is a crucial enzyme involved in bridging two metabolic pathways, gating the use of glutamate for either amino acid metabolism, or carbohydrate metabolism. The present study investigated GDH from tail muscle of the freshwater crayfish Orconectes virilis exploring changes to kinetic properties, phosphorylation levels and structural stability between two forms of the enzyme (aerobic control and 20-h severe hypoxic). Evidence indicated that GDH was converted to a high phosphate form under oxygen limitation. ProQ Diamond phosphoprotein staining showed a 42% higher bound phosphate content on GDH from muscle of severely hypoxic crayfish compared with the aerobic form, and treatment of this GDH with commercial phosphatase (alkaline phosphatase), and treatments that stimulated the activities of different endogenous protein phosphatases (stimulating PP1 + PP2A, PP2B, and PP2C) yielded significant increases in the fold activation by ADP of GDH from both control and severe hypoxic conditions. By contrast, stimulation of the activities of endogenous protein kinases (AMPK, PKA or CaMK) significantly reduced the ADP fold activation from control animals. The physiological consequence of severe hypoxia-induced GDH phosphorylation may be to suppress GDH activity under low oxygen, shutting off this critical bridge point between two metabolic pathways.

  5. STUDIES ON THE CARBOHYDRATE METABOLISM OF A GRAM-NEGATIVE ANAEROBE (BACTEROIDES SYMBIOSUS) USED IN THE CULTURE OF ENTAMOEBA HISTOLYTICA1

    PubMed Central

    Bragg, P. D.; Reeves, Richard E.

    1962-01-01

    Bragg, P. D. (Louisiana State University, New Orleans) and R. E. Reeves. Studies on the carbohydrate metabolism of a gram-negative anaerobe (Bacteroides symbiosus) used in the culture of Entamoeba histolytica. J. Bacteriol. 83:76–84. 1962—Resting cells of Bacteroides symbiosus have been shown to utilize glucose and several other monosaccharides. The fermentation of the sugars is mediated by demonstrable kinases except in the case of mannitol. The main end products of metabolism of glucose are CO2, H2, ethanol, and acetic, butyric, succinic, and lactic acids. Changes in the thiol used in the growth media produce different enzyme complements in the cells. Thus, cells grown with cysteine as the thiol are unable to metabolize glucosamine, whereas those grown with thiomalate rapidly degrade the amino sugar. The results of the enzyme assay and the results from experiments with C14-labelled glucose suggest that glucose is metabolized by resting cells mainly by the Embden-Myerhof pathway. PMID:13872395

  6. Infectious, inflammatory, and metabolic diseases affecting the athlete's spine.

    PubMed

    Metz, Lionel N; Wustrack, Rosanna; Lovell, Alberto F; Sawyer, Aenor J

    2012-07-01

    Sports and weight-bearing activities can have a positive effect on bone health in the growing, mature, or aging athlete. However, certain athletic activities and training regimens may place the athlete at increased risk for stress fractures in the spine. In addition, some athletes have an underlying susceptibility to fracture due to either systemic or focal abnormalities. It is important to identify and treat these athletes in order to prevent stress fractures and reduce the risk of osteoporosis in late adulthood. Therefore, the pre-participation physical examination offers a unique opportunity to screen athletes for metabolic bone disease through the history and physical examination. Positive findings warrant a thorough workup including a metabolic bone laboratory panel, and possibly a DEXA scan, which includes a lateral spine view.

  7. Carbohydrates: functionality in foods.

    PubMed

    Chinachoti, P

    1995-04-01

    Many functional requirements are met by the use of simple and complex carbohydrates in food. Carbohydrates offer a wide range of rheological and other properties, including solubility, cryoprotection, sweetening effect, hygroscopicity, crystallization inhibition, flavor encapsulation, and coating ability. These properties are based on chemical structure and interactions with other molecules through hydrogen bonding, ionic effect, and the formation of complexes with lipids and proteins. The ability to understand these properties directly affects the development of food products and processes. Thus, the functionality of carbohydrates in foods integrates precise knowledge of chemical structure and behavior with practical applications in the development and preparation of foods.

  8. How aneuploidy affects metabolic control and causes cancer.

    PubMed Central

    Rasnick, D; Duesberg, P H

    1999-01-01

    The complexity and diversity of cancer-specific phenotypes, including de-differentiation, invasiveness, metastasis, abnormal morphology and metabolism, genetic instability and progression to malignancy, have so far eluded explanation by a simple, coherent hypothesis. However, an adaptation of Metabolic Control Analysis supports the 100-year-old hypothesis that aneuploidy, an abnormal number of chromosomes, is the cause of cancer. The results demonstrate the currently counter-intuitive principle that it is the fraction of the genome undergoing differential expression, not the magnitude of the differential expression, that controls phenotypic transformation. Transforming the robust normal phenotype into cancer requires a twofold increase in the expression of thousands of normal gene products. The massive change in gene dose produces highly non-linear (i.e. qualitative) changes in the physiology and metabolism of cells and tissues. Since aneuploidy disrupts the natural balance of mitosis proteins, it also explains the notorious genetic instability of cancer cells as a consequence of the perpetual regrouping of chromosomes. In view of this and the existence of non-cancerous aneuploidy, we propose that cancer is the phenotype of cells above a certain threshold of aneuploidy. This threshold is reached either by the gradual, stepwise increase in the level of aneuploidy as a consequence of the autocatalysed genetic instability of aneuploid cells or by tetraploidization followed by a gradual loss of chromosomes. Thus the initiation step of carcinogenesis produces aneuploidy below the threshold for cancer, and the promotion step increases the level of aneuploidy above this threshold. We conclude that aneuploidy offers a simple and coherent explanation for all the cancer-specific phenotypes. Accordingly, the gross biochemical abnormalities, abnormal cellular size and morphology, the appearance of tumour-associated antigens, the high levels of secreted proteins responsible for

  9. Effects of red pitaya juice supplementation on cardiovascular and hepatic changes in high-carbohydrate, high-fat diet-induced metabolic syndrome rats

    PubMed Central

    2014-01-01

    Background The fruit of Hylocereus polyrhizus, also known as red pitaya, and buah naga in Malay, is one of the tropical fruits of the cactus family, Cactaceae. Red pitaya has been shown to protect aorta from oxidative damage and improve lipid profiles in hypercholesterolemic rats probably due to phytochemicals content including phenolics and flavonoids. The aim of this study was to investigate the changes in cardiac stiffness, hepatic and renal function in high-carbohydrate, high-fat diet-induced obese rats following supplementation of red pitaya juice. Methods Total 48 male Wistar rats were divided into 4 groups: corn-starch group (CS), corn-starch + red pitaya juice group (CRP), high-carbohydrate, high fat group (HCHF) and high-carbohydrate, high fat + red pitaya juice (HRP). The intervention with 5% red pitaya juice was started for 8 weeks after 8 weeks initiation of the diet. Heart function was determined ex vivo with Langendorff hearts while plasma liver enzymes, uric acid and urea were measured using commercial kits. Total fat mass was determined with Dual-energy X-ray absorptiometry (DXA) scan. Glucose uptake was measured with Oral Glucose Tolerance Test (OGTT). Liver and cardiac structures were defined by histology. Results Supplementation of red pitaya juice for 8 weeks increased energy intake and abdominal circumference but no change in body fat and lean mass respectively. Also, there were a trend of uric acid and glucose normalization for HRP as compared to H-fed rats. Red pitaya juice treatment reduced ALP and ALT but caused significant increment in AST. Diastolic stiffness of the heart was reduced after supplementation of red pitaya juice in corn starch fed rats. However, the reduction was not significant in HRP rats in comparison with H rats. Conclusion The present study concluded that red pitaya juice may serve as a complimentary therapy for attenuating some signs of metabolic syndrome. PMID:24919841

  10. Seasonal Temperature Changes Do Not Affect Cardiac Glucose Metabolism

    PubMed Central

    Schildt, Jukka; Loimaala, Antti; Hippeläinen, Eero; Nikkinen, Päivi; Ahonen, Aapo

    2015-01-01

    FDG-PET/CT is widely used to diagnose cardiac inflammation such as cardiac sarcoidosis. Physiological myocardial FDG uptake often creates a problem when assessing the possible pathological glucose metabolism of the heart. Several factors, such as fasting, blood glucose, and hormone levels, influence normal myocardial glucose metabolism. The effect of outdoor temperature on myocardial FDG uptake has not been reported before. We retrospectively reviewed 29 cancer patients who underwent PET scans in warm summer months and again in cold winter months. We obtained myocardial, liver, and mediastinal standardized uptake values (SUVs) as well as quantitative cardiac heterogeneity and the myocardial FDG uptake pattern. We also compared age and body mass index to other variables. The mean myocardial FDG uptake showed no significant difference between summer and winter months. Average outdoor temperature did not correlate significantly with myocardial SUVmax in either summer or winter. The heterogeneity of myocardial FDG uptake did not differ significantly between seasons. Outdoor temperature seems to have no significant effect on myocardial FDG uptake or heterogeneity. Therefore, warming the patients prior to attending cardiac PET studies in order to reduce physiological myocardial FDG uptake seems to be unnecessary. PMID:26858844

  11. Loading-induced changes in synovial fluid affect cartilage metabolism.

    PubMed

    van de Lest, C H; van den Hoogen, B M; van Weeren, P R

    2000-01-01

    The object of this study was to determine whether changes in the synovial fluid (SF) induced by in vivo loading can alter the metabolic activity of chondrocytes in vitro, and, if so, whether insulin-like growth factor-I (IGF-I) is responsible for this effect. Therefore, SF was collected from ponies after a period of box rest and after they had been exercised for a week. Normal, unloaded articular cartilage explants were cultured in 20% solutions of these SFs for 4 days and chondrocyte bioactivity was determined by glycosaminoglycan (GAG) turnover (i.e., the incorporation of 35SO4 into GAG and the release of GAG into the medium). Furthermore, the extent to which the bioactivity is IGF-I-dependent was determined in a cartilage explant culture in 20% SF, in the presence and absence of anti-IGF-I antibodies. In explants cultured in post-exercise SF, GAG synthesis was enhanced and GAG release was diminished when compared to cultures in pre-exercise SF. SF analysis showed that IGF-I and IGFBP-3 levels were increased in post-exercise SF. There was a positive correlation between IGF-I levels and proteoglycan synthesis, but no correlation between IGF-I levels and proteoglycan release. Addition of anti-IGF-I antibodies significantly inhibited stimulation of proteoglycan synthesis in explants cultured in SF with 40%. However, there was no difference in inhibition of proteoglycan synthesis between pre- and post-exercise SF which indicated that the relative contribution of IGF-I in the stimulating effect of SF did not change. Proteoglycan release was not influenced by the presence of anti-IGF-I antibodies. It is concluded that chondrocyte metabolic activity is at least partially regulated by changes in the SF induced by in vivo loading. Exercise altered the SF in a way that it had a favourable effect on cartilage PG content by enhancing the PG synthesis and reducing the PG breakdown. IGF-I is an important contributor to the overall stimulating effect of SF on cartilage

  12. Feedbacks between earlywood anatomy and non-structural carbohydrates affect spring phenology and wood production in ring-porous oaks

    NASA Astrophysics Data System (ADS)

    Pérez-de-Lis, Gonzalo; García-González, Ignacio; Rozas, Vicente; Olano, José Miguel

    2016-10-01

    Non-structural carbohydrates (NSC) play a central role in the construction and maintenance of a tree's vascular system, but feedbacks between the NSC status of trees and wood formation are not fully understood. We aimed to evaluate multiple dependencies among wood anatomy, winter NSC, and phenology for coexisting temperate (Quercus robur) and sub-Mediterranean (Q. pyrenaica) oaks along a water-availability gradient in the NW Iberian Peninsula. Sapwood NSC concentrations were quantified at three sites in December 2012 (N = 240). Leaf phenology and wood anatomy were surveyed in 2013. Structural equation modelling was used to analyse the interplay among hydraulic diameter (Dh), winter NSC, budburst date, and earlywood vessel production (EVP), while the effect of Dh and EVP on latewood width was assessed by using a mixed-effects model. NSC and wood production increased under drier conditions for both species. Q. robur showed a narrower Dh and lower soluble sugar (SS) concentration (3.88-5.08 % dry matter) than Q. pyrenaica (4.06-5.57 % dry matter), but Q. robur exhibited larger EVP and wider latewood (1403 µm) than Q. pyrenaica (667 µm). Stem diameter and Dh had a positive effect on SS concentrations, which were related to an earlier leaf flushing in both species. Sapwood sugar content appeared to limit EVP exclusively in Q. pyrenaica. In turn, Dh and EVP were found to be key predictors of latewood growth. Our results confirm that sapwood SS concentrations are involved in modulating growth resumption and xylem production in spring. Q. pyrenaica exhibited a tighter control of carbohydrate allocation to wood formation than Q. robur, which would play a role in protecting against environmental stress in the sub-Mediterranean area.

  13. Carbohydrate Stress Affecting Fruitlet Abscission and Expression of Genes Related to Auxin Signal Transduction Pathway in Litchi

    PubMed Central

    Kuang, Jian-Fei; Wu, Jian-Yang; Zhong, Hai-Ying; Li, Cai-Qin; Chen, Jian-Ye; Lu, Wang-Jin; Li, Jian-Guo

    2012-01-01

    Auxin, a vital plant hormone, regulates a variety of physiological and developmental processes. It is involved in fruit abscission through transcriptional regulation of many auxin-related genes, including early auxin responsive genes (i.e., auxin/indole-3-acetic acid (AUX/IAA), Gretchen Hagen3 (GH3) and small auxin upregulated (SAUR)) and auxin response factors (ARF), which have been well characterized in many plants. In this study, totally five auxin-related genes, including one AUX/IAA (LcAUX/IAA1), one GH3 (LcGH3.1), one SAUR (LcSAUR1) and two ARFs (LcARF1 and LcARF2), were isolated and characterized from litchi fruit. LcAUX/IAA1, LcGH3.1, LcSAUR1, LcARF1 and LcARF2 contain open reading frames (ORFs) encoding polypeptides of 203, 613, 142, 792 and 832 amino acids, respectively, with their corresponding molecular weights of 22.67, 69.20, 11.40, 88.20 and 93.16 kDa. Expression of these genes was investigated under the treatment of girdling plus defoliation which aggravated litchi fruitlet abscission due to the blockage of carbohydrates transport and the reduction of endogenous IAA content. Results showed that transcript levels of LcAUX/IAA1, LcGH3.1 and LcSAUR1 mRNAs were increased after the treatment in abscission zone (AZ) and other tissues, in contrast to the decreasing accumulation of LcARF1 mRNA, suggesting that LcAUX/IAA1, LcSAUR1 and LcARF1 may play more important roles in abscission. Our results provide new insight into the process of fruitlet abscission induced by carbohydrate stress and broaden our understanding of the auxin signal transduction pathway in this process at the molecular level. PMID:23443112

  14. Can Cholesterol Metabolism Modulation Affect Brain Function and Behavior?

    PubMed

    Cartocci, Veronica; Servadio, Michela; Trezza, Viviana; Pallottini, Valentina

    2017-02-01

    Cholesterol is an important component for cell physiology. It regulates the fluidity of cell membranes and determines the physical and biochemical properties of proteins. In the central nervous system, cholesterol controls synapse formation and function and supports the saltatory conduction of action potential. In recent years, the role of cholesterol in the brain has caught the attention of several research groups since a breakdown of cholesterol metabolism has been associated with different neurodevelopmental and neurodegenerative diseases, and interestingly also with psychiatric conditions. The aim of this review is to summarize the current knowledge about the connection between cholesterol dysregulation and various neurologic and psychiatric disorders based on clinical and preclinical studies. J. Cell. Physiol. 232: 281-286, 2017. © 2016 Wiley Periodicals, Inc.

  15. How does fish metamorphosis affect aromatic amino acid metabolism?

    PubMed

    Pinto, Wilson; Figueira, Luís; Dinis, Maria Teresa; Aragão, Cláudia

    2009-02-01

    Aromatic amino acids (AAs, phenylalanine and tyrosine) may be specifically required during fish metamorphosis, since they are the precursors of thyroid hormones which regulate this process. This project attempted to evaluate aromatic AA metabolism during the ontogenesis of fish species with a marked (Senegalese sole; Solea senegalensis) and a less accentuated metamorphosis (gilthead seabream; Sparus aurata). Fish were tube-fed with three L-[U-14C] AA solutions at pre-metamorphic, metamorphic and post-metamorphic stages of development: controlled AA mixture (Mix), phenylalanine (Phe) and tyrosine (Tyr). Results showed a preferential aromatic AA retention during the metamorphosis of Senegalese sole, rather than in gilthead seabream. Senegalese sole's highly accentuated metamorphosis seems to increase aromatic AA physiological requirements, possibly for thyroid hormone production. Thus, Senegalese sole seems to be especially susceptible to dietary aromatic AA deficiencies during the metamorphosis period, and these findings may be important for physiologists, fish nutritionists and the flatfish aquaculture industry.

  16. Ghrelin: a metabolic signal affecting the reproductive system.

    PubMed

    Lorenzi, Teresa; Meli, Rosaria; Marzioni, Daniela; Morroni, Manrico; Baragli, Alessandra; Castellucci, Mario; Gualillo, Oreste; Muccioli, Giampiero

    2009-04-01

    Ghrelin, an acylated 28 amino acid gastric peptide, was isolated from the stomach as an endogenous ligand for growth hormone (GH) secretagogue receptor in 1999. Circulating ghrelin is mainly produced by specific cells in the stomach's oxyntic glands. Ghrelin potently stimulates GH release and food intake and exhibits diverse effects, including ones on glucose metabolism and on secretion and motility of the gastrointestinal tract. Besides these effects on food intake and energy homeostasis, ghrelin is also involved in controlling reproductive functions, and a role for it as a novel regulator of the hypothalamic-pituitary gonadal axis is clearly emerging. We review recent ghrelin research with emphasis on its roles in the reproductive axis.

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

    PubMed Central

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

    2012-01-01

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

  18. Metabolic differences in temperamental Brahman cattle can affect productivity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many factors may adversely affect the growth and productivity of livestock. These include stressors associated with management practices, such as weaning, handling relative to transportation, and vaccination, that can modulate growth through the production of stress-related hormones (i.e., cortisol,...

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

    PubMed

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

    2011-08-01

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

  20. In vivo effects of cadmium chloride on certain aspects of carbohydrate metabolism in the tissues of a freshwater field crab Barytelphusa guerini

    SciTech Connect

    Reddy, S.L.N.; Venugopal, N.B.R.K.; Ramana Rao, J.V. )

    1989-06-01

    Cadmium is a toxic, non-essential heavy metal inhibiting numerous enzymes with functional sulfhydryl groups. Among the animals, aquatic organisms are most sensitive to heavy metals. Various aspects of toxic effects of cadmium pollution on fishes have been extensively reviewed. Survey of literature reveals that relatively few attempts have been made on the various aspects of cadmium toxicity in crustaceans and these studies were mainly devoted to marine forms. The freshwater crustaceans, particularly the freshwater field crab, Barytelphusa guerini, received less attention. This crab forms one of the major components of the paddy field ecosystem and has an edible importance among local populations. Apart from this, these crabs are easily available, maintainable in the laboratory and data obtained in this study can be extrapolated to other crustaceans. The present study reports the influence of cadmium on certain aspects of carbohydrate metabolism in the tissues of the freshwater field crab, Barytelphusa guerini, exposed to sublethal concentration of cadmium chloride.

  1. Hormonal imbalance and disturbances in carbohydrate metabolism associated with chronic feeding of high sucrose low magnesium diet in weanling male wistar rats.

    PubMed

    Garg, Meenakshi; Mehra, Pranav; Bansal, Devi Dayal

    2014-04-01

    This study was designed to determine chronic effect of high sucrose low magnesium (HSLM) diet in weanling rats on plasma thyroid profile, catecholamines and activities of key hepatic glycolytic, and gluconeogenic enzymes. Compared to control diet fed group, significantly elevated levels of plasma triiodothyronine, tetraiodothyronine, catecholamines (epinephrine, norepinephrine, and dopamine) and activity of hepatic glycolytic (hexokinase and glucokinase), and gluconeogenic (glucose-6-phosphatase) enzymes were observed in high sucrose and low magnesium fed groups. However, HSLM diet had an additive effect on all these three parameters. The study thus, assumes significance as it shows that hormonal imbalance and disorders in carbohydrate metabolism at an early stage of development can be due to dietary modification or due to deficiency of key element magnesium.

  2. Carbohydrate Loading.

    ERIC Educational Resources Information Center

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  3. Ameliorating effect of betanin, a natural chromoalkaloid by modulating hepatic carbohydrate metabolic enzyme activities and glycogen content in streptozotocin - nicotinamide induced experimental rats.

    PubMed

    Dhananjayan, Indumathi; Kathiroli, Sujithra; Subramani, Srinivasan; Veerasamy, Vinothkumar

    2017-04-01

    Betanin, a chromoalkaloid of beetroot, has shown significant biological effects of antioxidants, anti-inflammatory and anticarcinogenic activities. So, we attempted to determine whether betanin (a natural pigment) would be protective against hyperglycemia in streptozotocin (STZ) - nicotinamide (NA) induced diabetic rats. Rats were injected with STZ (40mg/kgb.w.) 15 mins after the administration of NA (110mg/kgb.w.) by intraperitonially (i.p.) 30days for the induction of experimental diabetes mellitus. After 72h diabetic rats were treated with betanin orally at a doses of 10, 20 and 40mg/kg b.w., respectively in a dose dependent manner and glibenclamide (600μg/kgb.w.). The promising character of betanin against diabetic rats was evaluated by performing the various biochemical parameters and histomorphological changes in liver and pancreas. Among the three doses, 20mg/kgb.w. of betanin was able to positively regulate plasma glucose, insulin, glycosylated hemoglobin (HbA1c) and hemoglobin (Hb) levels by significantly increasing the activity of glycolytic enzyme (glucokinase and pyruvate kinase), glucose-6-phosphate dehydrogenase and significantly decreasing the activity of gluconeogenic enzymes (glucose-6-phosphatase and fructose-1,6-bisphosphatase) thereby increasing the glycogen content in the liver. We put forward that betanin could significantly restore the levels of carbohydrate metabolic key enzymes to near normal in diabetic rat. Immunohistochemical observation of pancreas revealed that betanin treated diabetic rats showed increased insulin immunoreactive β-cells, which confirmed the biochemical findings. Taken together, present study suggests that betanin modulates the carbohydrate metabolism and has beneficial effects in glucose homeostasis.

  4. Simple and robust determination of the activity signature of key carbohydrate metabolism enzymes for physiological phenotyping in model and crop plants.

    PubMed

    Jammer, Alexandra; Gasperl, Anna; Luschin-Ebengreuth, Nora; Heyneke, Elmien; Chu, Hyosub; Cantero-Navarro, Elena; Großkinsky, Dominik K; Albacete, Alfonso A; Stabentheiner, Edith; Franzaring, Jürgen; Fangmeier, Andreas; van der Graaff, Eric; Roitsch, Thomas

    2015-09-01

    The analysis of physiological parameters is important to understand the link between plant phenotypes and their genetic bases, and therefore is needed as an important element in the analysis of model and crop plants. The activities of enzymes involved in primary carbohydrate metabolism have been shown to be strongly associated with growth performance, crop yield, and quality, as well as stress responses. A simple, fast, and cost-effective method to determine activities for 13 key enzymes involved in carbohydrate metabolism has been established, mainly based on coupled spectrophotometric kinetic assays. The comparison of extraction buffers and requirement for dialysis of crude protein extracts resulted in a universal protein extraction protocol, suitable for the preparation of protein extracts from different organs of various species. Individual published kinetic activity assays were optimized and adapted for a semi-high-throughput 96-well assay format. These assays proved to be robust and are thus suitable for physiological phenotyping, enabling the characterization and diagnosis of the physiological state. The potential of the determination of distinct enzyme activity signatures as part of a physiological fingerprint was shown for various organs and tissues from three monocot and five dicot model and crop species, including two case studies with external stimuli. Differential and specific enzyme activity signatures are apparent during inflorescence development and upon in vitro cold treatment of young inflorescences in the monocot ryegrass, related to conditions for doubled haploid formation. Likewise, treatment of dicot spring oilseed rape with elevated CO2 concentration resulted in distinct patterns of enzyme activity responses in leaves.

  5. [Metabolic studies in brothers affected by alcaptonuria (ochronosis)].

    PubMed

    Pugge, H R; Orozco, M; Toledo, A; Ripoll, J; Katz, J; Toledo, I; Pellanda, R

    1978-01-01

    The case of two brothers affected by alcaptonurie is reported. The activity of the homogenthisycasa enzyme has been determined by the material obtained through percutaneous biopsy. Concentrations of the aminoacids producing fenilalanina and thiroxina in their parents' blood have been investigated, the tests showing lack of liver enzyme and normal concentration of the amount of aminoacids in blood. Some aspects of skin lesion have been briefly reported and methods for treatment presented.

  6. Loading-induced changes in synovial fluid affect cartilage metabolism.

    PubMed

    Van den Hoogen, B M; van de Lest, C H; van Weeren, P R; Lafeber, F P; Lopes-Cardozo, M; van Golde, L M; Barneveld, A

    1998-06-01

    The purpose of this study was to determine whether changes in the synovial fluid (SF) induced by in vivo loading can induce an alteration in the metabolic activity of chondrocytes in vitro. Therefore, SF was collected from ponies after a period of box rest and after they had exercise for a week. Normal, unloaded articular cartilage explants were cultured in 20% solutions of these SFs for 4 days and chondrocyte activity was determined by glycosaminoglycan (GAG) turnover. In explants cultured in post-exercise SF, GAG synthesis was enhanced and GAG release was diminished when compared to cultures in pre-exercise SF. SF analysis showed that levels of insulin-like growth factors (IGF-I and IGF-II) tended to be higher in post-exercise SF, while no differences were found in metalloproteinase activity, hyaluronic acid and protein concentrations. This study showed that anabolic effects of joint loading on cartilage are, at least partially, mediated by alterations in the SF.

  7. Down-regulation of tomato PHYTOL KINASE strongly impairs tocopherol biosynthesis and affects prenyllipid metabolism in an organ-specific manner

    PubMed Central

    Almeida, Juliana; Azevedo, Mariana da Silva; Spicher, Livia; Glauser, Gaétan; vom Dorp, Katharina; Guyer, Luzia; del Valle Carranza, Andrea; Asis, Ramón; de Souza, Amanda Pereira; Buckeridge, Marcos; Demarco, Diego; Bres, Cécile; Rothan, Christophe; Peres, Lázaro Eustáquio Pereira; Hörtensteiner, Stefan; Kessler, Félix; Dörmann, Peter; Carrari, Fernando; Rossi, Magdalena

    2016-01-01

    Tocopherol, a compound with vitamin E (VTE) activity, is a conserved constituent of the plastidial antioxidant network in photosynthetic organisms. The synthesis of tocopherol involves the condensation of an aromatic head group with an isoprenoid prenyl side chain. The latter, phytyl diphosphate, can be derived from chlorophyll phytol tail recycling, which depends on phytol kinase (VTE5) activity. How plants co-ordinate isoprenoid precursor distribution for supplying biosynthesis of tocopherol and other prenyllipids in different organs is poorly understood. Here, Solanum lycopersicum plants impaired in the expression of two VTE5-like genes identified by phylogenetic analyses, named SlVTE5 and SlFOLK, were characterized. Our data show that while SlFOLK does not affect tocopherol content, the production of this metabolite is >80% dependent on SlVTE5 in tomato, in both leaves and fruits. VTE5 deficiency greatly impacted lipid metabolism, including prenylquinones, carotenoids, and fatty acid phytyl esters. However, the prenyllipid profile greatly differed between source and sink organs, revealing organ-specific metabolic adjustments in tomato. Additionally, VTE5-deficient plants displayed starch accumulation and lower CO2 assimilation in leaves associated with mild yield penalty. Taken together, our results provide valuable insights into the distinct regulation of isoprenoid metabolism in leaves and fruits and also expose the interaction between lipid and carbon metabolism, which results in carbohydrate export blockage in the VTE5-deficient plants, affecting tomato fruit quality. PMID:26596763

  8. Childhood obesity affects adult metabolic syndrome and diabetes.

    PubMed

    Liang, Yajun; Hou, Dongqing; Zhao, Xiaoyuan; Wang, Liang; Hu, Yuehua; Liu, Junting; Cheng, Hong; Yang, Ping; Shan, Xinying; Yan, Yinkun; Cruickshank, J Kennedy; Mi, Jie

    2015-09-01

    We seek to observe the association between childhood obesity by different measures and adult obesity, metabolic syndrome (MetS), and diabetes. Thousand two hundred and nine subjects from "Beijing Blood Pressure Cohort Study" were followed 22.9 ± 0.5 years in average from childhood to adulthood. We defined childhood obesity using body mass index (BMI) or left subscapular skinfold (LSSF), and adult obesity as BMI ≥ 28 kg/m(2). MetS was defined according to the joint statement of International Diabetes Federation and American Heart Association with modified waist circumference (≥ 90/85 cm for men/women). Diabetes was defined as fasting plasma glucose ≥ 7.0 mmol/L or blood glucose 2 h after oral glucose tolerance test ≥ 11.1 mmol/L or currently using blood glucose-lowering agents. Multiple linear and logistic regression models were used to assess the association. The incidence of adult obesity was 13.4, 60.0, 48.3, and 65.1 % for children without obesity, having obesity by BMI only, by LSSF only, and by both, respectively. Compared to children without obesity, children obese by LSSF only or by both had higher risk of diabetes. After controlling for adult obesity, childhood obesity predicted independently long-term risks of diabetes (odds ratio 2.8, 95 % confidence interval 1.2-6.3) or abdominal obesity (2.7, 1.6-4.7) other than MetS as a whole (1.2, 0.6-2.4). Childhood obesity predicts long-term risk of adult diabetes, and the effect is independent of adult obesity. LSSF is better than BMI in predicting adult diabetes.

  9. Environmental and physiological factors affecting the succinate product ratio during carbohydrate fermentation by Actinobacillus sp. 130Z.

    PubMed

    Van der Werf, M J; Guettler, M V; Jain, M K; Zeikus, J G

    1997-06-01

    Actinobacillus sp. 130Z fermented glucose to the major products succinate, acetate, and formate. Ethanol was formed as a minor fermentation product. Under CO2-limiting conditions, less succinate and more ethanol were formed. The fermentation product ratio remained constant at pH values from 6.0 to 7.4. More succinate was produced when hydrogen was present in the gas phase. Actinobacillus sp. 130Z grew at the expense of fumarate and l-malate reduction, with hydrogen as an electron donor. Other substrates such as more-reduced carbohydrates (e.g., d-sorbitol) resulted in higher succinate and/or ethanol production. Actinobacillus sp. 130Z contained the key enzymes involved in the Embden-Meyerhof-Parnas and the pentose-phosphate pathways and contained high levels of phosphoenolpyruvate (PEP) carboxykinase, malate dehydrogenase, fumarase, fumarate reductase, pyruvate kinase, pyruvate formate-lyase, phosphotransacetylase, acetate kinase, malic enzyme, and oxaloacetate decarboxylase. The levels of PEP carboxykinase, malate dehydrogenase, and fumarase were significantly higher in Actinobacillus sp. 130Z than in Escherichia coli K-12 and accounted for the differences in succinate production. Key enzymes in end product formation in Actinobacillus sp. 130Z were regulated by the energy substrates.

  10. Response to carbohydrate and fat refeeding in the expression of genes involved in nutrient partitioning and metabolism: striking effects on fibroblast growth factor-21 induction.

    PubMed

    Sánchez, J; Palou, A; Picó, C

    2009-12-01

    This study aimed to assess the effects of carbohydrate (CHO) and fat intake on the expression of key genes related with nutrient partitioning and metabolism in main tissues involved in energy metabolism (white adipose tissue, liver, and skeletal muscle). Rats were studied under different conditions: feeding state, 24 h fasting, and 12 h refeeding after 24 h fasting with isocaloric amounts of CHO or fat. Fat, but not CHO, refeeding was associated with an increase in serum and liver triglyceride content. Main changes in gene expression elicited by CHO compared with fat refeeding were: 1) higher expression levels of genes related with lipogenesis (PPARgamma2, ChREBP, FAS), glucose uptake and metabolism (GLUT4, HKII), fatty acid uptake (LPL, CD36), and lipolysis (ATGL, HSL) in white adipose tissue; 2) higher expression levels of genes related with lipogenesis (FAS, SCD1) but lower ones related with fatty acid uptake (CD36) and oxidation (PPARalpha, CPT1, PDK4) in liver; and 3) higher expression levels of GLUT4 but lower ones related with fatty acid oxidation (PDK4 and UCP3) in muscle. It is worth mentioning that both CHO and fat refeeding resulted in a robust increase in both hepatic mRNA and circulating levels of fibroblast growth factor-21, compared with fasted levels. In summary, these results, showing marked differences in gene expression after CHO and fat refeeding, can explain diet-associated differences in fuel handling and partitioning between tissues; in addition, a role of fibroblast growth factor-21 in metabolic adaptations, not only in the ketotic state but also to face an unbalanced nutritional situation, is suggested.

  11. Planteose as a storage carbohydrate required for early stage of germination of Orobanche minor and its metabolism as a possible target for selective control.

    PubMed

    Wakabayashi, Takatoshi; Joseph, Benesh; Yasumoto, Shuhei; Akashi, Tomoyoshi; Aoki, Toshio; Harada, Kazuo; Muranaka, Satoru; Bamba, Takeshi; Fukusaki, Eiichiro; Takeuchi, Yasutomo; Yoneyama, Koichi; Muranaka, Toshiya; Sugimoto, Yukihiro; Okazawa, Atsushi

    2015-06-01

    Root parasitic weeds in Orobanchaceae cause serious damage to worldwide agriculture. Germination of the parasites requires host-derived germination stimulants, such as strigolactones, as indicators of host roots within reach of the parasite's radicles. This unique germination process was focused on to identify metabolic pathways required for germination, and to design a selective control strategy. A metabolomic analysis of germinating seeds of clover broomrape, Orobanche minor, was conducted to identify its distinctive metabolites. Consequently, a galactosyl-sucrose trisaccharide, planteose (α-d-galactopyranosyl-(1→6)-β-d-fructofuranosyl-(2→1)-α-d-glucopyranoside), was identified as a metabolite that decreased promptly after reception of the germination stimulant. To investigate the importance of planteose metabolism, the effects of several glycosidase inhibitors were examined, and nojirimycin bisulfite (NJ) was found to alter the sugar metabolism and to selectively inhibit the germination of O. minor. Planteose consumption was similar in NJ-treated seeds and non-treated germinating seeds; however, NJ-treated seeds showed lower consumption of sucrose, a possible intermediate of planteose metabolism, resulting in significantly less glucose and fructose. This inhibitory effect was recovered by adding glucose. These results suggest that planteose is a storage carbohydrate required for early stage of germination of O. minor, and NJ inhibits germination by blocking the supply of essential glucose from planteose and sucrose. Additionally, NJ selectively inhibited radicle elongation of germinated seeds of Orobanchaceae plants (Striga hermonthica and Phtheirospermum japonicum). Thus, NJ will be a promising tool to develop specific herbicides to the parasites, especially broomrapes, and to improve our understanding of the molecular mechanisms of this unique germination.

  12. Comparative Genomics of Two Closely Related Unicellular Thermo-Acidophilic Red Algae, Galdieria sulphuraria and Cyanidioschyzon merolae, Reveals the Molecular Basis of the Metabolic Flexibility of Galdieria sulphuraria and Significant Differences in Carbohydrate Metabolism of Both Algae1

    PubMed Central

    Barbier, Guillaume; Oesterhelt, Christine; Larson, Matthew D.; Halgren, Robert G.; Wilkerson, Curtis; Garavito, R. Michael; Benning, Christoph; Weber, Andreas P.M.

    2005-01-01

    Unicellular algae serve as models for the study and discovery of metabolic pathways, for the functional dissection of cell biological processes such as organellar division and cell motility, and for the identification of novel genes and gene functions. The recent completion of several algal genome sequences and expressed sequence tag collections and the establishment of nuclear and organellar transformation methods has opened the way for functional genomics approaches using algal model systems. The thermo-acidophilic unicellular red alga Galdieria sulphuraria represents a particularly interesting species for a genomics approach owing to its extraordinary metabolic versatility such as heterotrophic and mixotrophic growth on more than 50 different carbon sources and its adaptation to hot acidic environments. However, the ab initio prediction of genes required for unknown metabolic pathways from genome sequences is not trivial. A compelling strategy for gene identification is the comparison of similarly sized genomes of related organisms with different physiologies. Using this approach, candidate genes were identified that are critical to the metabolic versatility of Galdieria. Expressed sequence tags and high-throughput genomic sequence reads covering >70% of the G. sulphuraria genome were compared to the genome of the unicellular, obligate photoautotrophic red alga Cyanidioschyzon merolae. More than 30% of the Galdieria sequences did not relate to any of the Cyanidioschyzon genes. A closer inspection of these sequences revealed a large number of membrane transporters and enzymes of carbohydrate metabolism that are unique to Galdieria. Based on these data, it is proposed that genes involved in the uptake of reduced carbon compounds and enzymes involved in their metabolism are crucial to the metabolic flexibility of G. sulphuraria. PMID:15710685

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

    PubMed

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

    2012-06-01

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

  14. Altered carbohydrate metabolism in the storage roots of sweet potato plants overexpressing the SRF1 gene, which encodes a Dof zinc finger transcription factor.

    PubMed

    Tanaka, Masaru; Takahata, Yasuhiro; Nakayama, Hiroki; Nakatani, Makoto; Tahara, Makoto

    2009-09-01

    In order to characterize the functions of the sweetpotato SRF1 gene, which encodes a Dof zinc finger transcriptional factor preferentially expressed in the storage roots, we isolated its full length cDNA and produced transgenic sweetpotato plants with altered SRF1 expression levels. The isolated cDNA of SRF1 encoded a polypeptide of 497 amino acids and was closely related to the cyclic Dof factors of Arabidopsis and the ascorbate oxidase binding protein of pumpkin. SRF1 was most highly expressed in storage roots, although some expression was also observed in other vegetative tissue. Transgenic plants overexpressing SRF1 showed significantly higher storage root dry matter content compared to the original cultivar Kokei No. 14 or control transgenic plants. In these plants, the starch content per fresh weight of the storage roots was also higher than that of the wild-type plants, while the glucose and fructose content drastically decreased. Among the enzymes involved in the sugar metabolism, soluble acid invertase showed a decreased activity in the transgenic plants. Gene expression analysis showed that the expression of Ibbetafruct2, which encodes an isoform of vacuolar invertase, was suppressed in the transgenic plants overexpressing the SRF1 gene. These data suggest that SRF1 modulates the carbohydrate metabolism in the storage roots through negative regulation of a vacuolar invertase gene.

  15. Expression patterns, activities and carbohydrate-metabolizing regulation of sucrose phosphate synthase, sucrose synthase and neutral invertase in pineapple fruit during development and ripening.

    PubMed

    Zhang, Xiu-Mei; Wang, Wei; Du, Li-Qing; Xie, Jiang-Hui; Yao, Yan-Li; Sun, Guang-Ming

    2012-01-01

    Differences in carbohydrate contents and metabolizing-enzyme activities were monitored in apical, medial, basal and core sections of pineapple (Ananas comosus cv. Comte de paris) during fruit development and ripening. Fructose and glucose of various sections in nearly equal amounts were the predominant sugars in the fruitlets, and had obvious differences until the fruit matured. The large rise of sucrose/hexose was accompanied by dramatic changes in sucrose phosphate synthase (SPS) and sucrose synthase (SuSy) activities. By contrast, neutral invertase (NI) activity may provide a mechanism to increase fruit sink strength by increasing hexose concentrations. Furthermore, two cDNAs of Ac-sps (accession no. GQ996582) and Ac-ni (accession no. GQ996581) were first isolated from pineapple fruits utilizing conserved amino-acid sequences. Homology alignment reveals that the amino acid sequences contain some conserved function domains. Transcription expression analysis of Ac-sps, Ac-susy and Ac-ni also indicated distinct patterns related to sugar accumulation and composition of pineapple fruits. It suggests that differential expressions of multiple gene families are necessary for sugar metabolism in various parts and developmental stages of pineapple fruit. A cycle of sucrose breakdown in the cytosol of sink tissues could be mediated through both Ac-SuSy and Ac-NI, and Ac-NI could be involved in regulating crucial steps by generating sugar signals to the cells in a temporally and spatially restricted fashion.

  16. Molecular Phenotyping of the pal1 and pal2 Mutants of Arabidopsis thaliana Reveals Far-Reaching Consequences on Phenylpropanoid, Amino Acid, and Carbohydrate Metabolism

    PubMed Central

    Rohde, Antje; Morreel, Kris; Ralph, John; Goeminne, Geert; Hostyn, Vanessa; De Rycke, Riet; Kushnir, Sergej; Van Doorsselaere, Jan; Joseleau, Jean-Paul; Vuylsteke, Marnik; Van Driessche, Gonzalez; Van Beeumen, Jozef; Messens, Eric; Boerjan, Wout

    2004-01-01

    The first enzyme of the phenylpropanoid pathway, Phe ammonia-lyase (PAL), is encoded by four genes in Arabidopsis thaliana. Whereas PAL function is well established in various plants, an insight into the functional significance of individual gene family members is lacking. We show that in the absence of clear phenotypic alterations in the Arabidopsis pal1 and pal2 single mutants and with limited phenotypic alterations in the pal1 pal2 double mutant, significant modifications occur in the transcriptome and metabolome of the pal mutants. The disruption of PAL led to transcriptomic adaptation of components of the phenylpropanoid biosynthesis, carbohydrate metabolism, and amino acid metabolism, revealing complex interactions at the level of gene expression between these pathways. Corresponding biochemical changes included a decrease in the three major flavonol glycosides, glycosylated vanillic acid, scopolin, and two novel feruloyl malates coupled to coniferyl alcohol. Moreover, Phe overaccumulated in the double mutant, and the levels of many other amino acids were significantly imbalanced. The lignin content was significantly reduced, and the syringyl/guaiacyl ratio of lignin monomers had increased. Together, from the molecular phenotype, common and specific functions of PAL1 and PAL2 are delineated, and PAL1 is qualified as being more important for the generation of phenylpropanoids. PMID:15377757

  17. Expression Patterns, Activities and Carbohydrate-Metabolizing Regulation of Sucrose Phosphate Synthase, Sucrose Synthase and Neutral Invertase in Pineapple Fruit during Development and Ripening

    PubMed Central

    Zhang, Xiu-Mei; Wang, Wei; Du, Li-Qing; Xie, Jiang-Hui; Yao, Yan-Li; Sun, Guang-Ming

    2012-01-01

    Differences in carbohydrate contents and metabolizing-enzyme activities were monitored in apical, medial, basal and core sections of pineapple (Ananas comosus cv. Comte de paris) during fruit development and ripening. Fructose and glucose of various sections in nearly equal amounts were the predominant sugars in the fruitlets, and had obvious differences until the fruit matured. The large rise of sucrose/hexose was accompanied by dramatic changes in sucrose phosphate synthase (SPS) and sucrose synthase (SuSy) activities. By contrast, neutral invertase (NI) activity may provide a mechanism to increase fruit sink strength by increasing hexose concentrations. Furthermore, two cDNAs of Ac-sps (accession no. GQ996582) and Ac-ni (accession no. GQ996581) were first isolated from pineapple fruits utilizing conserved amino-acid sequences. Homology alignment reveals that the amino acid sequences contain some conserved function domains. Transcription expression analysis of Ac-sps, Ac-susy and Ac-ni also indicated distinct patterns related to sugar accumulation and composition of pineapple fruits. It suggests that differential expressions of multiple gene families are necessary for sugar metabolism in various parts and developmental stages of pineapple fruit. A cycle of sucrose breakdown in the cytosol of sink tissues could be mediated through both Ac-SuSy and Ac-NI, and Ac-NI could be involved in regulating crucial steps by generating sugar signals to the cells in a temporally and spatially restricted fashion. PMID:22949808

  18. A suggested model for potato MIVOISAP involving functions of central carbohydrate and amino acid metabolism, as well as actin cytoskeleton and endocytosis.

    PubMed

    Ezquer, Ignacio; Li, Jun; Ovecka, Miroslav; Baroja-Fernández, Edurne; Muñoz, Francisco José; Montero, Manuel; Díaz de Cerio, Jessica; Hidalgo, Maite; Sesma, María Teresa; Bahaji, Abdellatif; Etxeberria, Ed; Pozueta-Romero, Javier

    2010-12-01

    We have recently found that microbial species ranging from Gram-negative and Gram-positive bacteria to different fungi emit volatiles that strongly promote starch accumulation in leaves of both mono- and di-cotyledonous plants. Transcriptome and enzyme activity analyses of potato leaves exposed to volatiles emitted by Alternaria alternata revealed that starch over-accumulation was accompanied by enhanced 3-phosphoglycerate to Pi ratio, and changes in functions involved in both central carbohydrate and amino acid metabolism. Exposure to microbial volatiles also promoted changes in the expression of genes that code for enzymes involved in endocytic uptake and traffic of solutes. With the overall data we propose a metabolic model wherein important determinants of accumulation of exceptionally high levels of starch include (a) upregulation of ADPglucose-producing SuSy, starch synthase III and IV, proteins involved in the endocytic uptake and traffic of sucrose, (b) down-regulation of acid invertase, starch breakdown enzymes and proteins involved in internal amino acid provision, and (c) 3-phosphoglycerate-mediated allosteric activation of ADPglucose pyrophosphorylase.

  19. Counting carbohydrates

    MedlinePlus

    ... There are 3 major types of carbohydrates: Sugars Starches Fiber Sugars are found naturally in some foods ... syrups, such as those added to canned fruit Starches are found naturally in foods. Your body breaks ...

  20. Lower vegetable protein intake and higher dietary acid load associated with lower carbohydrate intake are risk factors for metabolic syndrome in patients with type 2 diabetes: Post-hoc analysis of a cross-sectional study

    PubMed Central

    Iwase, Hiroya; Tanaka, Muhei; Kobayashi, Yukiko; Wada, Sayori; Kuwahata, Masashi; Kido, Yasuhiro; Hamaguchi, Masahide; Asano, Mai; Yamazaki, Masahiro; Hasegawa, Goji; Nakamura, Naoto; Fukui, Michiaki

    2015-01-01

    Aims/Introduction A low-carbohydrate diet based on animal sources is associated with higher all-cause mortality, whereas a vegetable-based low-carbohydrate diet is associated with lower cardiovascular disease mortality. It has been suggested that acid/base imbalance might play an important role in some cardiometabolic abnormalities. The aims of the present study were to evaluate whether carbohydrate intake is associated with quality of dietary protein and acid load, and whether these are related to metabolic syndrome in patients with type 2 diabetes. Materials and Methods The present cross-sectional study involved 149 patients with type 2 diabetes. Dietary intake was assessed using a validated self-administered diet history questionnaire. Dietary acid load was assessed by potential renal acid load and net endogenous acid production. Results Mean daily total energy intake, carbohydrate intake, animal protein intake and vegetable protein intake were 1821.5 kcal, 248.8 g, 36.1 g and 31.1 g, respectively. Carbohydrate energy/total energy was negatively correlated with animal protein energy/total energy, potential renal acid load or net endogenous acid production score, and was positively correlated with vegetable protein energy/total energy. Logistic regression analyses showed that the subgroup of patients with a lower vegetable protein energy/total energy or higher potential renal acid load or net endogenous acid production score was significantly associated with the prevalence of metabolic syndrome. Conclusions The present study showed that carbohydrate intake was associated with the quality of dietary protein and dietary acid load. Furthermore, decreased vegetable protein intake and increased dietary acid load were associated with the prevalence of metabolic syndrome. PMID:26221526

  1. A trial of reduced carbohydrate diet to improve metabolic outcomes and decrease adiposity in obese peripubertal African American girls: does macronutrient profile matter?

    PubMed Central

    Casazza, Krista; Cardel, Michelle; Dulin-Keita, Akilah; Hanks, Lynae J.; Gower, Barbara A.; Newton, Anna L.; Wallace, Stephenie

    2011-01-01

    Objectives Obesity prevalence among African American (AA) girls is higher than that of other groups. As typical calorie-restriction obesity treatment strategies have had limited success, alterations in macronutrient composition might effectively improve metabolic outcomes in this population and impact future body composition trajectories. The objective was to evaluate the efficacy of a moderately restricted carbohydrate (CHO) versus a standard CHO diet on weight/fat loss and metabolic parameters in overweight/obese AA girls aged 9–14 years. Methods A total of 26 AA girls (ranging from 92nd BMI percentile and above) were assigned to either a reduced- (SPEC: 42% calories from CHO, n=12) or a standard- (STAN: 55% of calories from CHO, n=14) CHO diet (protein held constant) for 16-weeks. All meals were provided and clinically tailored to meet the estimated energy requirements (REE × 1.2 in eucaloric phase and REE × 1.2 – 1000kcal in energy deficit phase). The first five-weeks encompassed a eucaloric phase evaluating metabolic changes in the absence of weight change. The subsequent 11-weeks were hypocaloric (1000kcal/d deficit) in effort to promote weight/fat loss. Meal tests were performed during the eucaloric phase for metabolic analyses. Dual-energy x-ray absorptiometry (DXA) was used to evaluate body composition. Results Both groups had reductions in weight/adiposity but the difference did not reach significance. The solid meal test indicated improved glucose/insulin homeostasis on the SPEC diet up to three hours post-ingestion. In addition, significantly lower triglycerides (p<0.001) were observed on the SPEC diet. Conclusions Dietary CHO reduction favorably influences metabolic parameters but did not result in greater weight/fat loss relative to a standard diet in obese AA girls. Future research is needed to determine long-term effectiveness of a reduced CHO diet on glucose and insulin homeostasis and how it may apply to weight maintenance/fat loss during

  2. Molecular insights into how a deficiency of amylose affects carbon allocation – carbohydrate and oil analyses and gene expression profiling in the seeds of a rice waxy mutant

    PubMed Central

    2012-01-01

    Background Understanding carbon partitioning in cereal seeds is of critical importance to develop cereal crops with enhanced starch yields for food security and for producing specified end-products high in amylose, β-glucan, or fructan, such as functional foods or oils for biofuel applications. Waxy mutants of cereals have a high content of amylopectin and have been well characterized. However, the allocation of carbon to other components, such as β-glucan and oils, and the regulation of the altered carbon distribution to amylopectin in a waxy mutant are poorly understood. In this study, we used a rice mutant, GM077, with a low content of amylose to gain molecular insight into how a deficiency of amylose affects carbon allocation to other end products and to amylopectin. We used carbohydrate analysis, subtractive cDNA libraries, and qPCR to identify candidate genes potentially responsible for the changes in carbon allocation in GM077 seeds. Results Carbohydrate analysis indicated that the content of amylose in GM077 seeds was significantly reduced, while that of amylopectin significantly rose as compared to the wild type BP034. The content of glucose, sucrose, total starch, cell-wall polysaccharides and oil were only slightly affected in the mutant as compared to the wild type. Suppression subtractive hybridization (SSH) experiments generated 116 unigenes in the mutant on the wild-type background. Among the 116 unigenes, three, AGP, ISA1 and SUSIBA2-like, were found to be directly involved in amylopectin synthesis, indicating their possible roles in redirecting carbon flux from amylose to amylopectin. A bioinformatics analysis of the putative SUSIBA2-like binding elements in the promoter regions of the upregulated genes indicated that the SUSIBA2-like transcription factor may be instrumental in promoting the carbon reallocation from amylose to amylopectin. Conclusion Analyses of carbohydrate and oil fractions and gene expression profiling on a global scale in the

  3. Impact of a carbohydrate-electrolyte drink on ingestive behaviour, affect and self-selected intensity during recreational exercise after 24-h fluid restriction.

    PubMed

    Peacock, Oliver J; Thompson, Dylan; Stokes, Keith A

    2013-01-01

    This study examined the effects of a carbohydrate-electrolyte drink on voluntary fluid intake, affect and self-selected intensity during recreational exercise after fluid restriction. In a randomised counterbalanced design, ten physically active adults were dehydrated via a 24-h period of fluid restriction before completing two 20-min bouts of cardiovascular exercise, 20-min of resistance exercise and 20 min on a cycle ergometer at a self-selected intensity with ad libitum access to water (W) or a carbohydrate-electrolyte solution (CES). Fluid restriction induced hypohydration of ∼1.2% initial body mass. Fluid intake during exercise was greater with CES (2105 ± 363 vs. 1470 ± 429 mL; P<0.01) and resulted in more adequate hydration (-0.03 ± 0.65 vs. -1.26 ± 0.80%; P<0.01). Plasma glucose concentrations (4.48 ± 0.40 vs. 4.28 ± 0.32 mmol L(-1); P<0.01) and pleasure ratings (2.63 ± 1.17 vs. 1.81 ± 1.37; P<0.01) were greater with CES than W. Mean power output during exercise performed at a self-selected intensity was 5.6% greater with CES (171 ± 63 vs. 162 ± 60 W; P<0.05). In physically active adults performing a 'real-life' recreational exercise simulation, CES resulted in more adequate hydration and an enhanced affective experience that corresponded with an increase in self-selected exercise intensity.

  4. The SEB-1 Transcription Factor Binds to the STRE Motif in Neurospora crassa and Regulates a Variety of Cellular Processes Including the Stress Response and Reserve Carbohydrate Metabolism

    PubMed Central

    Freitas, Fernanda Zanolli; Virgilio, Stela; Cupertino, Fernanda Barbosa; Kowbel, David John; Fioramonte, Mariana; Gozzo, Fabio Cesar; Glass, N. Louise; Bertolini, Maria Célia

    2016-01-01

    When exposed to stress conditions, all cells induce mechanisms resulting in an attempt to adapt to stress that involve proteins which, once activated, trigger cell responses by modulating specific signaling pathways. In this work, using a combination of pulldown assays and mass spectrometry analyses, we identified the Neurospora crassa SEB-1 transcription factor that binds to the Stress Response Element (STRE) under heat stress. Orthologs of SEB-1 have been functionally characterized in a few filamentous fungi as being involved in stress responses; however, the molecular mechanisms mediated by this transcription factor may not be conserved. Here, we provide evidences for the involvement of N. crassa SEB-1 in multiple cellular processes, including response to heat, as well as osmotic and oxidative stress. The Δseb-1 strain displayed reduced growth under these conditions, and genes encoding stress-responsive proteins were differentially regulated in the Δseb-1 strain grown under the same conditions. In addition, the SEB-1-GFP protein translocated from the cytosol to the nucleus under heat, osmotic, and oxidative stress conditions. SEB-1 also regulates the metabolism of the reserve carbohydrates glycogen and trehalose under heat stress, suggesting an interconnection between metabolism control and this environmental condition. We demonstrated that SEB-1 binds in vivo to the promoters of genes encoding glycogen metabolism enzymes and regulates their expression. A genome-wide transcriptional profile of the Δseb-1 strain under heat stress was determined by RNA-seq, and a broad range of cellular processes was identified that suggests a role for SEB-1 as a protein interconnecting these mechanisms. PMID:26994287

  5. Durum wheat seedling responses to simultaneous high light and salinity involve a fine reconfiguration of amino acids and carbohydrate metabolism.

    PubMed

    Woodrow, Pasqualina; Ciarmiello, Loredana F; Annunziata, Maria Grazia; Pacifico, Severina; Iannuzzi, Federica; Mirto, Antonio; D'Amelia, Luisa; Dell'Aversana, Emilia; Piccolella, Simona; Fuggi, Amodio; Carillo, Petronia

    2017-03-01

    Durum wheat plants are extremely sensitive to drought and salinity during seedling and early development stages. Their responses to stresses have been extensively studied to provide new metabolic targets and improving the tolerance to adverse environments. Most of these studies have been performed in growth chambers under low light [300-350 µmol m(-2) s(-1) photosynthetically active radiation (PAR), LL]. However, in nature plants have to face frequent fluctuations of light intensities that often exceed their photosynthetic capacity (900-2000 µmol m(-2) s(-1) ). In this study we investigated the physiological and metabolic changes potentially involved in osmotic adjustment and antioxidant defense in durum wheat seedlings under high light (HL) and salinity. The combined application of the two stresses decreased the water potential and stomatal conductance without reducing the photosynthetic efficiency of the plants. Glycine betaine (GB) synthesis was inhibited, proline and glutamate content decreased, while γ-aminobutyric acid (GABA), amides and minor amino acids increased. The expression level and enzymatic activities of Δ1-pyrroline-5-carboxylate synthetase, asparagine synthetase and glutamate decarboxylase, as well as other enzymatic activities of nitrogen and carbon metabolism, were analyzed. Antioxidant enzymes and metabolites were also considered. The results showed that the complex interplay seen in durum wheat plants under salinity at LL was simplified: GB and antioxidants did not play a main role. On the contrary, the fine tuning of few specific primary metabolites (GABA, amides, minor amino acids and hexoses) remodeled metabolism and defense processes, playing a key role in the response to simultaneous stresses.

  6. Inactivation of nitrate reductase alters metabolic branching of carbohydrate fermentation in the cyanobacterium Synechococcus sp. strain PCC 7002.

    PubMed

    Qian, Xiao; Kumaraswamy, G Kenchappa; Zhang, Shuyi; Gates, Colin; Ananyev, Gennady M; Bryant, Donald A; Dismukes, G Charles

    2016-05-01

    To produce cellular energy, cyanobacteria reduce nitrate as the preferred pathway over proton reduction (H2 evolution) by catabolizing glycogen under dark anaerobic conditions. This competition lowers H2 production by consuming a large fraction of the reducing equivalents (NADPH and NADH). To eliminate this competition, we constructed a knockout mutant of nitrate reductase, encoded by narB, in Synechococcus sp. PCC 7002. As expected, ΔnarB was able to take up intracellular nitrate but was unable to reduce it to nitrite or ammonia, and was unable to grow photoautotrophically on nitrate. During photoautotrophic growth on urea, ΔnarB significantly redirects biomass accumulation into glycogen at the expense of protein accumulation. During subsequent dark fermentation, metabolite concentrations--both the adenylate cellular energy charge (∼ATP) and the redox poise (NAD(P)H/NAD(P))--were independent of nitrate availability in ΔnarB, in contrast to the wild type (WT) control. The ΔnarB strain diverted more reducing equivalents from glycogen catabolism into reduced products, mainly H2 and d-lactate, by 6-fold (2.8% yield) and 2-fold (82.3% yield), respectively, than WT. Continuous removal of H2 from the fermentation medium (milking) further boosted net H2 production by 7-fold in ΔnarB, at the expense of less excreted lactate, resulting in a 49-fold combined increase in the net H2 evolution rate during 2 days of fermentation compared to the WT. The absence of nitrate reductase eliminated the inductive effect of nitrate addition on rerouting carbohydrate catabolism from glycolysis to the oxidative pentose phosphate (OPP) pathway, indicating that intracellular redox poise and not nitrate itself acts as the control switch for carbon flux branching between pathways.

  7. Effect of stress on hepatic 11beta-hydroxysteroid dehydrogenase activity and its influence on carbohydrate metabolism.

    PubMed

    Altuna, María Eugenia; Lelli, Sandra Marcela; San Martín de Viale, Leonor C; Damasco, María Cristina

    2006-10-01

    Stress activates the synthesis and secretion of catecholamines and adrenal glucocorticoids, increasing their circulating levels. In vivo, hepatic 11beta-hydroxysteroid dehydrogenase 1 (HSD1) stimulates the shift of 11-dehydrocorticosterone to corticosterone, enhancing active glucocorticoids at tissue level. We studied the effect of 3 types of stress, 1 induced by bucogastric overload with 200 mmol/L HCl causing metabolic acidosis (HCl), the second induced by bucogastric overload with 0.45% NaCl (NaCl), and the third induced by simulated overload (cannula), on the kinetics of hepatic HSD1 of rats and their influence on the activity of the gluconeogenic enzyme phosphoenolpyruvate carboxykinase, glycemia, and glycogen deposition. Compared with unstressed controls, all types of stress significantly increased HSD1 activity (146% cannula, 130% NaCl, and 253% HCl), phosphoenolpyruvate carboxykinase activity (51% cannula, 48% NaCl, and 86% HCl), and glycemia (29% cannula, 30% NaCl, and 41% HCl), but decreased hepatic glycogen (68% cannula, 68% NaCl, and 78% HCl). Owing to these results, we suggest the following events occur when stress is induced: an increase in hepatic HSD1 activity, augmented active glucocorticoid levels, increased gluconeogenesis, and glycemia. Also involved are the multiple events indirectly related to glucocorticoids, which lead to the depletion of hepatic glycogen deposits, thereby contributing to increased glycemia. This new approach shows that stress increments the activity of hepatic HSD1 and suggests that this enzyme could be involved in the development of the Metabolic Syndrome.

  8. Metabolic syndrome - the consequence of lifelong treatment of bipolar affective disorder.

    PubMed

    Dadić-Hero, Elizabeta; Ruzić, Klementina; Grahovac, Tanja; Petranović, Duska; Graovac, Mirjana; Palijan, Tija Zarković

    2010-06-01

    Mood disturbances are characteristic and dominant feature of Mood disorders. Bipolar Affective Disorder (BAD) is a mood disorder which occurs equally in both sexes. BAD may occur in co morbidity with other mental diseases and disorders such as: Anorexia Nervosa, Bulimia Nervosa, Attention Deficit, Panic Disorder and Social Phobia. However, medical disorders (one or more) can also coexist with BAD. Metabolic syndrome is a combination of metabolic disorders that increase the risk of developing cardiovascular disease. A 61-year old female patient has been receiving continuous and systematic psychiatric treatment for Bipolar Affective Disorder for the last 39 years. The first episode was a depressive one and it occurred after a child delivery. Seventeen years ago the patient developed diabetes (diabetes type II), and twelve years ago arterial hypertension was diagnosed. High cholesterol and triglyceride levels as well as weight gain were objective findings. During the last nine years she has been treated for lower leg ulcer. Since metabolic syndrome includes abdominal obesity, hypertension, diabetes mellitus, increased cholesterol and serum triglyceride levels, the aforesaid patient can be diagnosed with Metabolic Syndrome. When treating Bipolar Affective Disorder, the antipsychotic drug choice should be careful and aware of its side-effects in order to avoid the development or aggravation of metabolic syndrome.

  9. Beta- Lactam Antibiotics Stimulate Biofilm Formation in Non-Typeable Haemophilus influenzae by Up-Regulating Carbohydrate Metabolism

    PubMed Central

    Wu, Siva; Li, Xiaojin; Gunawardana, Manjula; Maguire, Kathleen; Guerrero-Given, Debbie; Schaudinn, Christoph; Wang, Charles; Baum, Marc M.; Webster, Paul

    2014-01-01

    Non-typeable Haemophilus influenzae (NTHi) is a common acute otitis media pathogen, with an incidence that is increased by previous antibiotic treatment. NTHi is also an emerging causative agent of other chronic infections in humans, some linked to morbidity, and all of which impose substantial treatment costs. In this study we explore the possibility that antibiotic exposure may stimulate biofilm formation by NTHi bacteria. We discovered that sub-inhibitory concentrations of beta-lactam antibiotic (i.e., amounts that partially inhibit bacterial growth) stimulated the biofilm-forming ability of NTHi strains, an effect that was strain and antibiotic dependent. When exposed to sub-inhibitory concentrations of beta-lactam antibiotics NTHi strains produced tightly packed biofilms with decreased numbers of culturable bacteria but increased biomass. The ratio of protein per unit weight of biofilm decreased as a result of antibiotic exposure. Antibiotic-stimulated biofilms had altered ultrastructure, and genes involved in glycogen production and transporter function were up regulated in response to antibiotic exposure. Down-regulated genes were linked to multiple metabolic processes but not those involved in stress response. Antibiotic-stimulated biofilm bacteria were more resistant to a lethal dose (10 µg/mL) of cefuroxime. Our results suggest that beta-lactam antibiotic exposure may act as a signaling molecule that promotes transformation into the biofilm phenotype. Loss of viable bacteria, increase in biofilm biomass and decreased protein production coupled with a concomitant up-regulation of genes involved with glycogen production might result in a biofilm of sessile, metabolically inactive bacteria sustained by stored glycogen. These biofilms may protect surviving bacteria from subsequent antibiotic challenges, and act as a reservoir of viable bacteria once antibiotic exposure has ended. PMID:25007395

  10. Circadian changes in core body temperature, metabolic rate and locomotor activity in rats on a high-protein, carbohydrate-free diet.

    PubMed

    Yamaoka, Ippei; Hagi, Mieko; Doi, Masako

    2009-12-01

    Ingestion of a high-protein meal results in body weight loss due to elevated energy expenditure, while also increasing satiety and decreasing subsequent food intake. The present study aimed to clarify the effects of a high-protein, carbohydrate-free diet (HPCFD) on these physiological indicators from a circadian perspective. Rats were given HPCFD or a pair-fed normal protein content diet (20% protein; NPD) for 4 d. The HPCFD group lost more body weight than the NPD group. Oxygen consumption (VO(2)) in the HPCFD group did not change during the experimental period, and tended to be higher during the light (L) phase than in the NPD group. Carbon dioxide production (VCO(2)) during the L phase was higher in the HPCFD group than in the NPD group, where VCO(2) was gradually decreased during the last dark (D) phase and throughout the L phase. The HPCFD group exhibited higher daily core body temperature (T(b)), particularly during the late D phase and throughout the L phase when compared to the NPD group. Locomotor activities during the D phase of the NPD group tended to gradually increase and were thus significantly higher than in the HPCFD group. These results suggest that HPCFD, even if energy intake is insufficient, maintains circadian changes in metabolic rates, resulting in maintenance of elevated daily T(b) and body weight reduction without increasing activity.

  11. Differential growth response and carbohydrate metabolism of global collection of perennial ryegrass accessions to submergence and recovery following de-submergence.

    PubMed

    Yu, Xiaoqing; Luo, Na; Yan, Jiapei; Tang, Jinchi; Liu, Shuwei; Jiang, Yiwei

    2012-07-15

    Submergence can severely affect the growth of perennial grasses. The variations in growth and the physiological responses of perennial grass germplasm to submergence stress are not well understood. The objective of this study was to characterize the responses of diverse perennial ryegrass accessions to submergence and their recovery following de-submergence. One hundred globally collected perennial ryegrass accessions were submerged for 7d followed by 7d of recovery in two experiments (Exp 1 and Exp 2), respectively. Compared to the pattern of the controls, the overall distribution in leaf color, chlorophyll fluorescence, plant height (HT), and growth rate (GR) shifted toward a high frequency of lower values under submergence in both experiments. The accessions were generally grouped into three types: fast growth with maintenance of color (escape, T1), slow growth with maintenance of color (quiescence, T2), and slow growth with loss of color (susceptible, ST). Under submergence, T1 had higher HT and GR than the other two groups except for GR of T2 in Exp 2 and had higher water-soluble carbohydrate (WSC) and fructan concentrations, as well as fructan to WSC ratio, than ST in Exp 1. Recovery of HT and GR were generally close to that of the control level except for HT of ST in Exp 2, but the carbohydrates fully recovered in all types of plants after 7d of de-submergence. Differential responses of perennial ryegrass accessions to submergence are useful in creating more tolerant materials and in further characterizing physiological and molecular mechanisms of submergence tolerance.

  12. Healthy carbohydrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Functional foods include dietary fiber consisting of health-promoting carbohydrates. We have produced novel prebiotics from orange peel and observed that they extend the shelf life of probiotic bacteria in synbiotics. Some pectic-oligosaccharides and xyloglucan-oligosaccharides also have anti-adhesi...

  13. Photosynthesis, Carbohydrate Metabolism, and Export in Beta vulgaris L. and Phaseolus vulgaris L. during Square and Sinusoidal Light Regimes.

    PubMed

    Fondy, B R; Geiger, D R; Servaites, J C

    1989-02-01

    Rates of photosynthesis, sucrose synthesis, starch accumulation and degradation were measured in sugar beet (Beta vulgaris L.) and bean (Phaseolus vulgaris L.) plants under a square-wave light regime and under a sinusoidal regime that simulated the natural daylight period. Photosynthesis rate increased in a measured manner in direct proportion to the increasing light level. In contrast to this close correspondence between photosynthesis and light, a lag in photosynthesis rate was seen during the initial hour under square-wave illumination. The leaf appeared to be responding to limits set by carbon metabolism rather than by gas exchange or light reactions. Under the sinusoidal regime starch degradation occurred during the first and last 2 hours of the photoperiod, likely in response to photosynthesis rate rather than directly to light level. Starch broke down when photosynthesis was below a threshold rate and accumulated above this rate. Under square-wave illumination, accumulation of starch did not begin until irradiance was at full level for an hour or more and photosynthesis was at or near its maximum. Under a sinusoidal light regime, sucrose synthesis rate comprised carbon that was newly fixed throughout the day plus that from starch degradation at the beginning and end of the day. Synthesis of sucrose from recently fixed carbon increased with increasing net carbon fixation rate while its formation from degradation of starch decreased correspondingly. The complementary sources of carbon maintained a relatively steady rate of sucrose synthesis under the changing daytime irradiance.

  14. Absence of cumulus cells during in vitro maturation affects lipid metabolism in bovine oocytes.

    PubMed

    Auclair, Sylvain; Uzbekov, Rustem; Elis, Sébastien; Sanchez, Laura; Kireev, Igor; Lardic, Lionel; Dalbies-Tran, Rozenn; Uzbekova, Svetlana

    2013-03-15

    Cumulus cells (CC) surround the oocyte and are coupled metabolically through regulation of nutrient intake. CC removal before in vitro maturation (IVM) decreases bovine oocyte developmental competence without affecting nuclear meiotic maturation. The objective was to investigate the influence of CC on oocyte cytoplasmic maturation in relation to energy metabolism. IVM with either cumulus-enclosed (CEO) or -denuded (DO) oocytes was performed in serum-free metabolically optimized medium. Transmission electron microscopy revealed different distribution of membrane-bound vesicles and lipid droplets between metaphase II DO and CEO. By Nile Red staining, a significant reduction in total lipid level was evidenced in DO. Global transcriptomic analysis revealed differential expression of genes regulating energy metabolism, transcription, and translation between CEO and DO. By Western blot, fatty acid synthase (FAS) and hormone-sensitive phospholipase (HSL) proteins were detected in oocytes and in CC, indicating a local lipogenesis and lypolysis. FAS protein was significantly less abundant in DO that in CEO and more highly expressed in CC than in the oocytes. On the contrary, HSL protein was more abundant in oocytes than in CC. In addition, active Ser⁵⁶³-phosphorylated HSL was detected in the oocytes only after IVM, and its level was similar in CEO and DO. In conclusion, absence of CC during IVM affected lipid metabolism in the oocyte and led to suboptimal cytoplasmic maturation. Thus, CC may influence the oocyte by orienting the consumption of nutritive storage via regulation of local fatty acid synthesis and lipolysis to provide energy for maturation.

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

    PubMed

    Bagci, Enise; Heijlen, Marjolein; Vergauwen, Lucia; Hagenaars, An; Houbrechts, Anne M; Esguerra, Camila V; Blust, Ronny; Darras, Veerle M; Knapen, Dries

    2015-01-01

    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 TH balance

  16. Stretching Your Energetic Budget: How Tendon Compliance Affects the Metabolic Cost of Running

    PubMed Central

    Uchida, Thomas K.; Hicks, Jennifer L.; Dembia, Christopher L.; Delp, Scott L.

    2016-01-01

    Muscles attach to bones via tendons that stretch and recoil, affecting muscle force generation and metabolic energy consumption. In this study, we investigated the effect of tendon compliance on the metabolic cost of running using a full-body musculoskeletal model with a detailed model of muscle energetics. We performed muscle-driven simulations of running at 2–5 m/s with tendon force–strain curves that produced between 1 and 10% strain when the muscles were developing maximum isometric force. We computed the average metabolic power consumed by each muscle when running at each speed and with each tendon compliance. Average whole-body metabolic power consumption increased as running speed increased, regardless of tendon compliance, and was lowest at each speed when tendon strain reached 2–3% as muscles were developing maximum isometric force. When running at 2 m/s, the soleus muscle consumed less metabolic power at high tendon compliance because the strain of the tendon allowed the muscle fibers to operate nearly isometrically during stance. In contrast, the medial and lateral gastrocnemii consumed less metabolic power at low tendon compliance because less compliant tendons allowed the muscle fibers to operate closer to their optimal lengths during stance. The software and simulations used in this study are freely available at simtk.org and enable examination of muscle energetics with unprecedented detail. PMID:26930416

  17. Xylitol affects the intestinal microbiota and metabolism of daidzein in adult male mice.

    PubMed

    Tamura, Motoi; Hoshi, Chigusa; Hori, Sachiko

    2013-12-10

    This study examined the effects of xylitol on mouse intestinal microbiota and urinary isoflavonoids. Xylitol is classified as a sugar alcohol and used as a food additive. The intestinal microbiota seems to play an important role in isoflavone metabolism. Xylitol feeding appears to affect the gut microbiota. We hypothesized that dietary xylitol changes intestinal microbiota and, therefore, the metabolism of isoflavonoids in mice. Male mice were randomly divided into two groups: those fed a 0.05% daidzein with 5% xylitol diet (XD group) and those fed a 0.05% daidzein-containing control diet (CD group) for 28 days. Plasma total cholesterol concentrations were significantly lower in the XD group than in the CD group (p < 0.05). Urinary amounts of equol were significantly higher in the XD group than in the CD group (p < 0.05). The fecal lipid contents (% dry weight) were significantly greater in the XD group than in the CD group (p < 0.01). The cecal microbiota differed between the two dietary groups. The occupation ratios of Bacteroides were significantly greater in the CD than in the XD group (p < 0.05). This study suggests that xylitol has the potential to affect the metabolism of daidzein by altering the metabolic activity of the intestinal microbiota and/or gut environment. Given that equol affects bone health, dietary xylitol plus isoflavonoids may exert a favorable effect on bone health.

  18. Learning about Carbohydrates

    MedlinePlus

    ... What Happens in the Operating Room? Learning About Carbohydrates KidsHealth > For Kids > Learning About Carbohydrates A A ... of energy for the body. Two Types of Carbohydrates There are two major types of carbohydrates (or ...

  19. Learning about Carbohydrates

    MedlinePlus

    ... dientes Video: Getting an X-ray Learning About Carbohydrates KidsHealth > For Kids > Learning About Carbohydrates Print A ... of energy for the body. Two Types of Carbohydrates There are two major types of carbohydrates (or ...

  20. The in vivo infusion of hydrogen peroxide induces oxidative stress and differentially affects the activities of small intestinal carbohydrate digestive enzymes in the neonatal pig.

    PubMed

    Lackeyram, D; Mine, Y; Widowski, T; Archbold, T; Fan, M Z

    2012-12-01

    Chronic fatigue syndrome (CFS) is characterized by persistent and relapsing fatigue that involves oxidative stress in its pathogenesis. We tested the hypothesis that a decrease in key carbohydrate-digesting enzyme activity in the gut is one of the major biological mechanisms of developing CFS in liquid formula-fed neonatal pigs with in vivo infusion of H(2)O(2). Piglets at 7 to 10 d of age were fitted with an intraperitoneal catheter, allowed a 3-d post surgical recovery, and infused with either H(2)O(2) at 5 mmol/kg BW (PER; n = 8) or the same volume of saline (CON; n = 8) in six 20-ml doses daily for a period of 10 d. During this period, animal behavior was monitored, blood samples collected, and jejunal enzyme activity kinetic experiments for lactase, sucrase, maltase, and maltase-glucoamylase were conducted. Plasma concentration of reduced glutathione remained similar (P > 0.05) to the pre-infusion level over the study duration in the CON group whereas this was 65% lower (P < 0.05) than the pre-infusion level in the PER group. Piglets experiencing oxidative stress had an overall lower (P < 0.05) physical mobility and the maximal jejunal specific activities [μmol/(mg protein · min)] for lactase (PER, 6.54 ± 0.68 vs. CON, 12.65 ± 0.69) and maltase (PER, 57.39 ± 1.02 vs. CON, 75.60 ± 1.04), respectively. However, differences were not observed (P > 0.05) in the maximal specific activities [μmol/(mg protein · min)] of sucrase (PER, 10.50 ± 1.37 vs. CON, 12.40 ± 1.55) and maltase-glucoamylase (PER, 0.71 ± 0.08 vs. CON, 0.70 ± 0.07) between the 2 groups. In conclusion, infusion of a suitable dose of H(2)O(2) induced CFS in the neonatal pigs. Oxidative stress in vivo differentially affected the maximal activities of important small intestinal carbohydrate-digesting enzymes in neonatal pigs fed a dairy milk-based liquid formula.

  1. Transcription Interference and ORF Nature Strongly Affect Promoter Strength in a Reconstituted Metabolic Pathway

    PubMed Central

    Carquet, Marie; Pompon, Denis; Truan, Gilles

    2015-01-01

    Fine tuning of individual enzyme expression level is necessary to alleviate metabolic imbalances in synthetic heterologous pathways. A known approach consists of choosing a suitable combination of promoters, based on their characterized strengths in model conditions. We questioned whether each step of a multiple-gene synthetic pathway could be independently tunable at the transcription level. Three open reading frames, coding for enzymes involved in a synthetic pathway, were combinatorially associated to different promoters on an episomal plasmid in Saccharomyces cerevisiae. We quantified the mRNA levels of the three genes in each strain of our generated combinatorial metabolic library. Our results evidenced that the ORF nature, position, and orientation induce strong discrepancies between the previously reported promoters’ strengths and the observed ones. We conclude that, in the context of metabolic reconstruction, the strength of usual promoters can be dramatically affected by many factors. Among them, transcriptional interference and ORF nature seem to be predominant. PMID:25767795

  2. Baroreflex sensitivity in acute hypoxia and carbohydrate loading.

    PubMed

    Klemenc, Matjaž; Golja, Petra

    2011-10-01

    Hypoxia decreases baroreflex sensitivity (BRS) and can be a sufficient cause for syncope in healthy individuals. Carbohydrate loading enhances efferent sympathetic activity, which affects cardiac contractility, heart rate and vascular resistance, the main determinants of blood pressure. Thus, in both normoxia and hypoxia, carbohydrate loading may be more than simply metabolically beneficial, as it may affect blood pressure regulation. We hypothesised that carbohydrate loading will, in both normoxia and hypoxia, alter the regulation of blood pressure, as reflected in a change in baroreflex sensitivity. Fourteen subjects participated in two experiments, composed of a 15-min normoxic period, after which the subjects ingested water or an equal amount of water with carbohydrates. A 30-min rest period was then followed by a 10-min second normoxic and a 30-min hypoxic period. Blood pressure and heart rate were monitored continuously during the experiment to determine BRS. Despite an increased sympathetic activation, reflected in increased heart rate (P < 0.001) BRS was lower (P < 0.01) after carbohydrate loading, as compared to the water experiment, in both normoxic [23.7 (12.4) versus 28.8 (13.8) ms/mmHg] and hypoxic [16.8 (11.0) versus 24.3 (12.3) ms/mmHg] phases of the present study. As BRS was decreased in acute hypoxic exposure, the results confirm that hypoxia interferes with blood pressure regulation. However, although oral carbohydrate loading induced sympathoexcitation, it did not improve blood pressure regulation in hypoxia, as evident from the BRS data. Baroreflex effects of other forms of carbohydrate loading, not causing postprandial blood shifts to digestive system, should therefore be investigated.

  3. Olanzapine and aripiprazole differentially affect glucose uptake and energy metabolism in human mononuclear blood cells.

    PubMed

    Stapel, Britta; Kotsiari, Alexandra; Scherr, Michaela; Hilfiker-Kleiner, Denise; Bleich, Stefan; Frieling, Helge; Kahl, Kai G

    2017-05-01

    The use of antipsychotics carries the risk of metabolic side effects, such as weight gain and new onset type-2 diabetes mellitus. The mechanisms of the observed metabolic alterations are not fully understood. We compared the effects of two atypical antipsychotics, one known to favor weight gain (olanzapine), the other not (aripiprazole), on glucose metabolism. Primary human peripheral blood mononuclear cells (PBMC) were isolated and stimulated with olanzapine or aripiprazole for 72 h. Cellular glucose uptake was analyzed in vitro by 18F-FDG uptake. Further measurements comprised mRNA expression of glucose transporter (GLUT) 1 and 3, GLUT1 protein expression, DNA methylation of GLUT1 promoter region, and proteins involved in downstream glucometabolic processes. We observed a 2-fold increase in glucose uptake after stimulation with aripiprazole. In contrast, olanzapine stimulation decreased glucose uptake by 40%, accompanied by downregulation of the cellular energy sensor AMP activated protein kinase (AMPK). GLUT1 protein expression increased, GLUT1 mRNA expression decreased, and GLUT1 promoter was hypermethylated with both antipsychotics. Pyruvat-dehydrogenase (PDH) complex activity decreased with olanzapine only. Our findings suggest that the atypical antipsychotics olanzapine and aripiprazole differentially affect energy metabolism in PBMC. The observed decrease in glucose uptake in olanzapine stimulated PBMC, accompanied by decreased PDH point to a worsening in cellular energy metabolism not compensated by AMKP upregulation. In contrast, aripiprazole stimulation lead to increased glucose uptake, while not affecting PDH complex expression. The observed differences may be involved in the different metabolic profiles observed in aripiprazole and olanzapine treated patients.

  4. Cardiac Metabolic Pathways Affected in the Mouse Model of Barth Syndrome

    PubMed Central

    Huang, Yan; Powers, Corey; Madala, Satish K.; Greis, Kenneth D.; Haffey, Wendy D.; Towbin, Jeffrey A.; Purevjav, Enkhsaikhan; Javadov, Sabzali; Strauss, Arnold W.; Khuchua, Zaza

    2015-01-01

    Cardiolipin (CL) is a mitochondrial phospholipid essential for electron transport chain (ETC) integrity. CL-deficiency in humans is caused by mutations in the tafazzin (Taz) gene and results in a multisystem pediatric disorder, Barth syndrome (BTHS). It has been reported that tafazzin deficiency destabilizes mitochondrial respiratory chain complexes and affects supercomplex assembly. The aim of this study was to investigate the impact of Taz-knockdown on the mitochondrial proteomic landscape and metabolic processes, such as stability of respiratory chain supercomplexes and their interactions with fatty acid oxidation enzymes in cardiac muscle. Proteomic analysis demonstrated reduction of several polypeptides of the mitochondrial respiratory chain, including Rieske and cytochrome c1 subunits of complex III, NADH dehydrogenase alpha subunit 5 of complex I and the catalytic core-forming subunit of F0F1-ATP synthase. Taz gene knockdown resulted in upregulation of enzymes of folate and amino acid metabolic pathways in heart mitochondria, demonstrating that Taz-deficiency causes substantive metabolic remodeling in cardiac muscle. Mitochondrial respiratory chain supercomplexes are destabilized in CL-depleted mitochondria from Taz knockdown hearts resulting in disruption of the interactions between ETC and the fatty acid oxidation enzymes, very long-chain acyl-CoA dehydrogenase and long-chain 3-hydroxyacyl-CoA dehydrogenase, potentially affecting the metabolic channeling of reducing equivalents between these two metabolic pathways. Mitochondria-bound myoglobin was significantly reduced in Taz-knockdown hearts, potentially disrupting intracellular oxygen delivery to the oxidative phosphorylation system. Our results identify the critical pathways affected by the Taz-deficiency in mitochondria and establish a future framework for development of therapeutic options for BTHS. PMID:26030409

  5. Cardiac metabolic pathways affected in the mouse model of barth syndrome.

    PubMed

    Huang, Yan; Powers, Corey; Madala, Satish K; Greis, Kenneth D; Haffey, Wendy D; Towbin, Jeffrey A; Purevjav, Enkhsaikhan; Javadov, Sabzali; Strauss, Arnold W; Khuchua, Zaza

    2015-01-01

    Cardiolipin (CL) is a mitochondrial phospholipid essential for electron transport chain (ETC) integrity. CL-deficiency in humans is caused by mutations in the tafazzin (Taz) gene and results in a multisystem pediatric disorder, Barth syndrome (BTHS). It has been reported that tafazzin deficiency destabilizes mitochondrial respiratory chain complexes and affects supercomplex assembly. The aim of this study was to investigate the impact of Taz-knockdown on the mitochondrial proteomic landscape and metabolic processes, such as stability of respiratory chain supercomplexes and their interactions with fatty acid oxidation enzymes in cardiac muscle. Proteomic analysis demonstrated reduction of several polypeptides of the mitochondrial respiratory chain, including Rieske and cytochrome c1 subunits of complex III, NADH dehydrogenase alpha subunit 5 of complex I and the catalytic core-forming subunit of F0F1-ATP synthase. Taz gene knockdown resulted in upregulation of enzymes of folate and amino acid metabolic pathways in heart mitochondria, demonstrating that Taz-deficiency causes substantive metabolic remodeling in cardiac muscle. Mitochondrial respiratory chain supercomplexes are destabilized in CL-depleted mitochondria from Taz knockdown hearts resulting in disruption of the interactions between ETC and the fatty acid oxidation enzymes, very long-chain acyl-CoA dehydrogenase and long-chain 3-hydroxyacyl-CoA dehydrogenase, potentially affecting the metabolic channeling of reducing equivalents between these two metabolic pathways. Mitochondria-bound myoglobin was significantly reduced in Taz-knockdown hearts, potentially disrupting intracellular oxygen delivery to the oxidative phosphorylation system. Our results identify the critical pathways affected by the Taz-deficiency in mitochondria and establish a future framework for development of therapeutic options for BTHS.

  6. [Effect of ATP and glutaminic acid on carbohydrate-energy and nitrogen metabolism in the rat brain and liver under the effect of pulsed electromagnetic field].

    PubMed

    Mishchenko, L I; Kolodub, F A

    1975-01-01

    Oxidative phosphorylation, content of lactate, creatine phosphate, ammonia and glutamine were studied as affected by ATP and glutaminic acid in the brain and liver of rat subjected to the action of the pulsed electromagnetic field of 7 kHz frequency (72 kA/m, 15 seances). ATP (1 mg per 100 g of weight) was found to have a normalizing effect on the processes of nitrogen metabolism in the rat brain, ATP increasing the intenstiy of the oxidative phosphorylation in the tissues of intact rats, has no analogous influence on the irradiated animals. With administration of glutaminic acid (5 mg per 100 g of weight) the processes of oxidative phosphorylation and nitrogen metabolism, disturbed under the effect of the pulsed electromagnetic field are normalized.

  7. Leucine metabolism regulates TRI6 expression and affects deoxynivalenol production and virulence in Fusarium graminearum.

    PubMed

    Subramaniam, Rajagopal; Narayanan, Swara; Walkowiak, Sean; Wang, Li; Joshi, Manisha; Rocheleau, Hélène; Ouellet, Thérèse; Harris, Linda J

    2015-11-01

    TRI6 is a positive regulator of the trichothecene gene cluster and the production of trichothecene mycotoxins [deoxynivalenol (DON)] and acetylated forms such as 15-Acetyl-DON) in the cereal pathogen Fusarium graminearum. As a global transcriptional regulator, TRI6 expression is modulated by nitrogen-limiting conditions, sources of nitrogen and carbon, pH and light. However, the mechanism by which these diverse environmental factors affect TRI6 expression remains underexplored. In our effort to understand how nutrients affect TRI6 regulation, comparative digital expression profiling was performed with a wild-type F. graminearum and a Δtri6 mutant strain, grown in nutrient-rich conditions. Analysis showed that TRI6 negatively regulates genes of the branched-chain amino acid (BCAA) metabolic pathway. Feeding studies with deletion mutants of MCC, encoding methylcrotonyl-CoA-carboxylase, one of the key enzymes of leucine metabolism, showed that addition of leucine specifically down-regulated TRI6 expression and reduced 15-ADON accumulation. Constitutive expression of TRI6 in the Δmcc mutant strain restored 15-ADON production. A combination of cellophane breach assays and pathogenicity experiments on wheat demonstrated that disrupting the leucine metabolic pathway significantly reduced disease. These findings suggest a complex interaction between one of the primary metabolic pathways with a global regulator of mycotoxin biosynthesis and virulence in F. graminearum.

  8. Effects of a low- or a high-carbohydrate diet on performance, energy system contribution, and metabolic responses during supramaximal exercise.

    PubMed

    Lima-Silva, Adriano E; Pires, Flavio O; Bertuzzi, Romulo; Silva-Cavalcante, Marcos D; Oliveira, Rodrigo S F; Kiss, Maria Augusta; Bishop, David

    2013-09-01

    The purpose of the present study was to examine the effects of a high- or low-carbohydrate (CHO) diet on performance, aerobic and anaerobic contribution, and metabolic responses during supramaximal exercise. Six physically-active men first performed a cycling exercise bout at 115% maximal oxygen uptake to exhaustion after following their normal diet for 48 h (∼50% of CHO, control test). Seventy-two hours after, participants performed a muscle glycogen depletion exercise protocol, followed by either a high- or low-CHO diet (∼70 and 25% of CHO, respectively) for 48 h, in a random, counterbalanced order. After the assigned diet period (48 h), the supramaximal cycling exercise bout (115% maximal oxygen consumption) to exhaustion was repeated. The low-CHO diet reduced time to exhaustion when compared with both the control and the high-CHO diet (-19 and -32%, respectively, p < 0.05). The reduced time to exhaustion following the low-CHO diet was accompanied by a lower total aerobic energy contribution (-39%) compared with the high-CHO diet (p < 0.05). However, the aerobic and anaerobic energy contribution at the shortest time to exhaustion (isotime) was similar among conditions (p > 0.05). The low-CHO diet was associated with a lower blood lactate concentration (p < 0.05), with no effect on the plasma concentration of insulin, glucose and K(+) (p > 0.05). In conclusion, a low-CHO diet reduces both performance and total aerobic energy provision during supramaximal exercise. As peak K(+) concentration was similar, but time to exhaustion shorter, the low-CHO diet was associated with an earlier attainment of peak plasma K(+) concentration.

  9. Responses to oleic, linoleic and α-linolenic acids in high-carbohydrate, high-fat diet-induced metabolic syndrome in rats.

    PubMed

    Poudyal, Hemant; Kumar, Senthil A; Iyer, Aarjit; Waanders, Jennifer; Ward, Leigh C; Brown, Lindsay

    2013-07-01

    We investigated the changes in adiposity, cardiovascular and liver structure and function, and tissue fatty acid compositions in response to oleic acid-rich macadamia oil, linoleic acid-rich safflower oil and α-linolenic acid-rich flaxseed oil (C18 unsaturated fatty acids) in rats fed either a diet high in simple sugars and mainly saturated fats or a diet high in polysaccharides (cornstarch) and low in fat. The fatty acids induced lipid redistribution away from the abdomen, more pronounced with increasing unsaturation; only oleic acid increased whole-body adiposity. Oleic acid decreased plasma total cholesterol without changing triglycerides and nonesterified fatty acids, whereas linoleic and α-linolenic acids decreased plasma triglycerides and nonesterified fatty acids but not cholesterol. α-Linolenic acid improved left ventricular structure and function, diastolic stiffness and systolic blood pressure. Neither oleic nor linoleic acid changed the left ventricular remodeling induced by high-carbohydrate, high-fat diet, but both induced dilation of the left ventricle and functional deterioration in low fat-diet-fed rats. α-Linolenic acid improved glucose tolerance, while oleic and linoleic acids increased basal plasma glucose concentrations. Oleic and α-linolenic acids, but not linoleic acid, normalized systolic blood pressure. Only oleic acid reduced plasma markers of liver damage. The C18 unsaturated fatty acids reduced trans fatty acids in the heart, liver and skeletal muscle with lowered stearoyl-CoA desaturase-1 activity index; linoleic and α-linolenic acids increased accumulation of their C22 elongated products. These results demonstrate different physiological and biochemical responses to primary C18 unsaturated fatty acids in a rat model of human metabolic syndrome.

  10. Structure of Bacteroides thetaiotaomicron BT2081 at 2.05 Å resolution: the first structural representative of a new protein family that may play a role in carbohydrate metabolism

    PubMed Central

    Yeh, Andrew P.; Abdubek, Polat; Astakhova, Tamara; Axelrod, Herbert L.; Bakolitsa, Constantina; Cai, Xiaohui; Carlton, Dennis; Chen, Connie; Chiu, Hsiu-Ju; Chiu, Michelle; Clayton, Thomas; Das, Debanu; Deller, Marc C.; Duan, Lian; Ellrott, Kyle; Farr, Carol L.; Feuerhelm, Julie; Grant, Joanna C.; Grzechnik, Anna; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K.; Klock, Heath E.; Knuth, Mark W.; Kozbial, Piotr; Krishna, S. Sri; Kumar, Abhinav; Lam, Winnie W.; Marciano, David; McMullan, Daniel; Miller, Mitchell D.; Morse, Andrew T.; Nigoghossian, Edward; Nopakun, Amanda; Okach, Linda; Puckett, Christina; Reyes, Ron; Tien, Henry J.; Trame, Christine B.; van den Bedem, Henry; Weekes, Dana; Wooten, Tiffany; Xu, Qingping; Hodgson, Keith O.; Wooley, John; Elsliger, Marc-André; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Wilson, Ian A.

    2010-01-01

    BT2081 from Bacteroides thetaiotaomicron (GenBank accession code NP_810994.1) is a member of a novel protein family consisting of over 160 members, most of which are found in the different classes of Bacteroidetes. Genome-context analysis lends support to the involvement of this family in carbohydrate metabolism, which plays a key role in B. thetaiotaomicron as a predominant bacterial symbiont in the human distal gut microbiome. The crystal structure of BT2081 at 2.05 Å resolution represents the first structure from this new protein family. BT2081 consists of an N-terminal domain, which adopts a β-sandwich immunoglobulin-like fold, and a larger C-terminal domain with a β-sandwich jelly-roll fold. Structural analyses reveal that both domains are similar to those found in various carbohydrate-active enzymes. The C-terminal β-jelly-roll domain contains a potential carbohydrate-binding site that is highly conserved among BT2081 homologs and is situated in the same location as the carbohydrate-binding sites that are found in structurally similar glycoside hydrolases (GHs). However, in BT2081 this site is partially occluded by surrounding loops, which results in a deep solvent-accessible pocket rather than a shallower solvent-exposed cleft. PMID:20944224

  11. The reduction in postprandial lipemia after exercise is independent of the relative contributions of fat and carbohydrate to energy metabolism during exercise.

    PubMed

    Malkova, D; Hardman, A E; Bowness, R J; Macdonald, I A

    1999-02-01

    A single session of exercise several hours before a high-fat meal reduces postprandial lipemia. The purpose of the present study was to test the hypothesis that this effect is independent of substrate metabolism during exercise. Twelve men aged 21 to 36 years underwent three oral fat tolerance tests with intervals of at least 1 week. On one occasion, only activities of daily living were allowed the preceding day (control). On the other two occasions, subjects ran on a treadmill for 90 minutes on the afternoon preceding the fat tolerance test; 90 minutes before running, they ingested either acipimox, an inhibitor of lipolysis in adipose tissue, or placebo. Acipimox abolished the increase in the nonesterified fatty acid (NEFA) concentration observed during the run after placebo and reduced lipid oxidation (placebo, 37 +/- 7 g; acipimox, 21 +/- 3 g; P < .05, mean +/- SEM), but had no effect on gross energy expenditure (placebo, 4.86 +/- 0.20 MJ; acipimox, 4.83 +/- 0.18 MJ). Before each of the three fat tolerance tests, subjects reported to the laboratory after an overnight fast. Blood samples were obtained in the fasted state and for 6 hours after consumption of a high-fat meal (per kilogram of body mass: 1.2 g fat, 1.2 g carbohydrate, and 61 kJ energy). Plasma concentrations of NEFA were higher postprandially with acipimox, compared with control and placebo (P < .05), as were glucose concentrations measured over the first 4 hours. The insulin response to the meal was lower in placebo compared with control and acipimox (P < .05). Despite these counterregulatory responses, postprandial lipemia was reduced to the same degree (compared with control, P < .05) by exercise preceded by acipimox and by exercise preceded by placebo (area under the plasma triacylglycerol concentration v time curve: control, 8.77 +/- 1.17 mmol/L x 6 h; placebo, 6.95 +/- 0.97 mmol/L x 6 h; acipimox, 6.81 +/- 0.81 mmol/L x 6 h). These findings suggest that some factor other than the nature of the

  12. Maternal Nutrition during Pregnancy Affects Testicular and Bone Development, Glucose Metabolism and Response to Overnutrition in Weaned Horses Up to Two Years

    PubMed Central

    Mendoza, Luis; Peugnet, Pauline; Dubois, Cédric; Dahirel, Michèle; Lejeune, Jean-Philippe; Caudron, Isabelle; Guenon, Isabelle; Camous, Sylvaine; Tarrade, Anne; Wimel, Laurence; Serteyn, Didier; Bouraima-Lelong, Hélène; Chavatte-Palmer, Pascale

    2017-01-01

    Introduction Pregnant mares and post-weaning foals are often fed concentrates rich in soluble carbohydrates, together with forage. Recent studies suggest that the use of concentrates is linked to alterations of metabolism and the development of osteochondrosis in foals. The aim of this study was to determine if broodmare diet during gestation affects metabolism, osteoarticular status and growth of yearlings overfed from 20 to 24 months of age and/or sexual maturity in prepubertal colts. Material and methods Twenty-four saddlebred mares were fed forage only (n = 12, group F) or cracked barley and forage (n = 12, group B) from mid-gestation until foaling. Colts were gelded at 12 months of age. Between 20 and 24 months of age, all yearlings were overfed (+140% of requirements) using an automatic concentrate feeder. Offspring were monitored for growth between 6 and 24 months of age, glucose homeostasis was evaluated via modified frequently sampled intra veinous glucose tolerance test (FSIGT) at 19 and 24 months of age and osteoarticular status was investigated using radiographic examinations at 24 months of age. The structure and function of testicles from prepubertal colts were analyzed using stereology and RT-qPCR. Results Post-weaning weight growth was not different between groups. Testicular maturation was delayed in F colts compared to B colts at 12 months of age. From 19 months of age, the cannon bone was wider in B vs F yearlings. F yearlings were more insulin resistant at 19 months compared to B yearlings but B yearlings were affected more severely by overnutrition with reduced insulin sensitivity. The osteoarticular status at 24 months of age was not different between groups. Conclusion In conclusion, nutritional management of the pregnant broodmare and the growing foal may affect sexual maturity of colts and the metabolism of foals until 24 months of age. These effects may be deleterious for reproductive and sportive performances in older horses. PMID

  13. Genetic modification of iron metabolism in mice affects the gut microbiota.

    PubMed

    Buhnik-Rosenblau, Keren; Moshe-Belizowski, Shirly; Danin-Poleg, Yael; Meyron-Holtz, Esther G

    2012-10-01

    The composition of the gut microbiota is affected by environmental factors as well as host genetics. Iron is one of the important elements essential for bacterial growth, thus we hypothesized that changes in host iron homeostasis, may affect the luminal iron content of the gut and thereby the composition of intestinal bacteria. The iron regulatory protein 2 (Irp2) and one of the genes mutated in hereditary hemochromatosis Hfe , are both proteins involved in the regulation of systemic iron homeostasis. To test our hypothesis, fecal metal content and a selected spectrum of the fecal microbiota were analyzed from Hfe-/-, Irp2-/- and their wild type control mice. Elevated levels of iron as well as other minerals in feces of Irp2-/- mice compared to wild type and Hfe-/- mice were observed. Interestingly significant variation in the general fecal-bacterial population-patterns was observed between Irp2-/- and Hfe-/- mice. Furthermore the relative abundance of five species, mainly lactic acid bacteria, was significantly different among the mouse lines. Lactobacillus (L.) murinus and L. intestinalis were highly abundant in Irp2-/- mice, Enterococcus faecium species cluster and a species most similar to Olsenella were highly abundant in Hfe-/- mice and L. johnsonii was highly abundant in the wild type mice. These results suggest that deletion of iron metabolism genes in the mouse host affects the composition of its intestinal bacteria. Further studying the relationship between gut microbiota and genetic mutations affecting systemic iron metabolism in human should lead to clinical implications.

  14. Carbohydrate Metabolism in Submariner Personnel

    DTIC Science & Technology

    1983-06-01

    46: 1549-1557; 1967 4. Kraft, J.R. Detection of diabetes mellitus in situ (occult diabetes). Laboratory Med. 6: 10-22; 1975 5. Wright, H.F. and...tolerance: Role of muscle glycogen. Med.& Sci. in Sport & Exercise 14: 150; 1982 -17 ~174 - _ APPEDIX I From: Kraft, J.R. Detection of diabetes mellitus in...results are considered indicative of prediabetes or occult diabetes (also called diabetes in situ), the earliest detectable phase of diabetes mellitus . The

  15. Epigallocatechin gallate affects glucose metabolism and increases fitness and lifespan in Drosophila melanogaster.

    PubMed

    Wagner, Anika E; Piegholdt, Stefanie; Rabe, Doerte; Baenas, Nieves; Schloesser, Anke; Eggersdorfer, Manfred; Stocker, Achim; Rimbach, Gerald

    2015-10-13

    In this study, we tested whether a standardized epigallocatechin-3-gallate (EGCG) rich green tea extract (comprising > 90% EGCG) affects fitness and lifespan as well as parameters of glucose metabolism and energy homeostasis in the fruit fly, Drosophila melanogaster. Following the application of the green tea extract a significant increase in the mean lifespan (+ 3.3 days) and the 50% survival (+ 4.3 days) as well as improved fitness was detected. These effects went along an increased expression of Spargel, the homolog of mammalian PGC1α, which has been reported to affect lifespan in flies. Intriguingly, in flies, treatment with the green tea extract decreased glucose concentrations, which were accompanied by an inhibition of α-amylase and α-glucosidase activity. Computational docking analysis proved the potential of EGCG to dock into the substrate binding pocket of α-amylase and to a greater extent into α-glucosidase. Furthermore, we demonstrate that EGCG downregulates insulin-like peptide 5 and phosphoenolpyruvate carboxykinase, major regulators of glucose metabolism, as well as the Drosophila homolog of leptin, unpaired 2. We propose that a decrease in glucose metabolism in connection with an upregulated expression of Spargel contribute to the better fitness and the extended lifespan in EGCG-treated flies.

  16. Silver nanoparticles affect glucose metabolism in hepatoma cells through production of reactive oxygen species

    PubMed Central

    Lee, Mi Jin; Lee, Seung Jun; Yun, Su Jin; Jang, Ji-Young; Kang, Hangoo; Kim, Kyongmin; Choi, In-Hong; Park, Sun

    2016-01-01

    The silver nanoparticle (AgNP) is a candidate for anticancer therapy because of its effects on cell survival and signaling. Although numerous reports are available regarding their effect on cell death, the effect of AgNPs on metabolism is not well understood. In this study, we investigated the effect of AgNPs on glucose metabolism in hepatoma cell lines. Lactate release from both HepG2 and Huh7 cells was reduced with 5 nm AgNPs as early as 1 hour after treatment, when cell death did not occur. Treatment with 5 nm AgNPs decreased glucose consumption in HepG2 cells but not in Huh7 cells. Treatment with 5 nm AgNPs reduced nuclear factor erythroid 2-like 2 expression in both cell types without affecting its activation at the early time points after AgNPs’ treatment. Increased reactive oxygen species (ROS) production was detected 1 hour after 5 nm AgNPs’ treatment, and lactate release was restored in the presence of an ROS scavenger. Our results suggest that 5 nm AgNPs affect glucose metabolism by producing ROS. PMID:26730190

  17. Epigallocatechin gallate affects glucose metabolism and increases fitness and lifespan in Drosophila melanogaster

    PubMed Central

    Wagner, Anika E.; Piegholdt, Stefanie; Rabe, Doerte; Baenas, Nieves; Schloesser, Anke; Eggersdorfer, Manfred; Stocker, Achim; Rimbach, Gerald

    2015-01-01

    In this study, we tested whether a standardized epigallocatechin-3-gallate (EGCG) rich green tea extract (comprising > 90% EGCG) affects fitness and lifespan as well as parameters of glucose metabolism and energy homeostasis in the fruit fly, Drosophila melanogaster. Following the application of the green tea extract a significant increase in the mean lifespan (+ 3.3 days) and the 50% survival (+ 4.3 days) as well as improved fitness was detected. These effects went along an increased expression of Spargel, the homolog of mammalian PGC1α, which has been reported to affect lifespan in flies. Intriguingly, in flies, treatment with the green tea extract decreased glucose concentrations, which were accompanied by an inhibition of α-amylase and α-glucosidase activity. Computational docking analysis proved the potential of EGCG to dock into the substrate binding pocket of α-amylase and to a greater extent into α-glucosidase. Furthermore, we demonstrate that EGCG downregulates insulin-like peptide 5 and phosphoenolpyruvate carboxykinase, major regulators of glucose metabolism, as well as the Drosophila homolog of leptin, unpaired 2. We propose that a decrease in glucose metabolism in connection with an upregulated expression of Spargel contribute to the better fitness and the extended lifespan in EGCG-treated flies. PMID:26375250

  18. Antimicrobial drug resistance affects broad changes in metabolomic phenotype in addition to secondary metabolism

    PubMed Central

    Derewacz, Dagmara K.; Goodwin, Cody R.; McNees, C. Ruth; McLean, John A.; Bachmann, Brian O.

    2013-01-01

    Bacteria develop resistance to many classes of antibiotics vertically, by engendering mutations in genes encoding transcriptional and translational apparatus. These severe adaptations affect global transcription, translation, and the correspondingly affected metabolism. Here, we characterize metabolome scale changes in transcriptional and translational mutants in a genomically characterized Nocardiopsis, a soil-derived actinomycete, in stationary phase. Analysis of ultra-performance liquid chromatography–ion mobility–mass spectrometry metabolomic features from a cohort of streptomycin- and rifampicin-resistant mutants grown in the absence of antibiotics exhibits clear metabolomic speciation, and loadings analysis catalogs a marked change in metabolic phenotype. Consistent with derepression, up to 311 features are observed in antibiotic-resistant mutants that are not detected in their progenitors. Mutants demonstrate changes in primary metabolism, such as modulation of fatty acid composition and the increased production of the osmoprotectant ectoine, in addition to the presence of abundant emergent potential secondary metabolites. Isolation of three of these metabolites followed by structure elucidation demonstrates them to be an unusual polyketide family with a previously uncharacterized xanthene framework resulting from sequential oxidative carbon skeletal rearrangements. Designated as “mutaxanthenes,” this family can be correlated to a type II polyketide gene cluster in the producing organism. Taken together, these data suggest that biosynthetic pathway derepression is a general consequence of some antibiotic resistance mutations. PMID:23341601

  19. Silver nanoparticles affect glucose metabolism in hepatoma cells through production of reactive oxygen species.

    PubMed

    Lee, Mi Jin; Lee, Seung Jun; Yun, Su Jin; Jang, Ji-Young; Kang, Hangoo; Kim, Kyongmin; Choi, In-Hong; Park, Sun

    2016-01-01

    The silver nanoparticle (AgNP) is a candidate for anticancer therapy because of its effects on cell survival and signaling. Although numerous reports are available regarding their effect on cell death, the effect of AgNPs on metabolism is not well understood. In this study, we investigated the effect of AgNPs on glucose metabolism in hepatoma cell lines. Lactate release from both HepG2 and Huh7 cells was reduced with 5 nm AgNPs as early as 1 hour after treatment, when cell death did not occur. Treatment with 5 nm AgNPs decreased glucose consumption in HepG2 cells but not in Huh7 cells. Treatment with 5 nm AgNPs reduced nuclear factor erythroid 2-like 2 expression in both cell types without affecting its activation at the early time points after AgNPs' treatment. Increased reactive oxygen species (ROS) production was detected 1 hour after 5 nm AgNPs' treatment, and lactate release was restored in the presence of an ROS scavenger. Our results suggest that 5 nm AgNPs affect glucose metabolism by producing ROS.

  20. Metabolic myopathies

    NASA Technical Reports Server (NTRS)

    Martin, A.; Haller, R. G.; Barohn, R.; Blomqvist, C. G. (Principal Investigator)

    1994-01-01

    Metabolic myopathies are disorders of muscle energy production that result in skeletal muscle dysfunction. Cardiac and systemic metabolic dysfunction may coexist. Symptoms are often intermittent and provoked by exercise or changes in supply of lipid and carbohydrate fuels. Specific disorders of lipid and carbohydrate metabolism in muscle are reviewed. Evaluation often requires provocative exercise testing. These tests may include ischemic forearm exercise, aerobic cycle exercise, and 31P magnetic resonance spectroscopy with exercise.

  1. Cool-night temperature induces spike emergence and affects photosynthetic efficiency and metabolizable carbohydrate and organic acid pools in Phalaenopsis aphrodite.

    PubMed

    Chen, Wen-Huei; Tseng, Ya-Chen; Liu, Yo-Ching; Chuo, Chuo-Min; Chen, Pai-Ting; Tseng, Kai-Meng; Yeh, Yi-Chun; Ger, Mang-Jye; Wang, Heng-Long

    2008-10-01

    After being acclimated to constant warm (28 degrees C day/28 degrees C night) and cool-night temperature (28 degrees C day/20 degrees C night) regimes in growth chambers for 2 weeks, the two groups of mature Phalaenopsis aphrodite subsp. formosana plants both clearly exhibited a diurnal oscillation of stomatal conductance, net CO(2) uptake rate, malate and starch levels, and the phosphoenolpyruvate carboxylase (EC 4.1.1.31) and NAD(+)-malic enzyme (EC 1.1.1.39) activities. Hence, P. aphrodite is an obligate crassulacean acid metabolism plant. Nevertheless, different night temperature greatly affected both the stomatal conductance and the contribution of ambient and respiratory CO(2) to the nocturnal accumulation of malate. However, the amounts of nocturnal accumulated malate and daily deposited starch appeared to have no significant difference between the two groups. These results demonstrate that P. ahrodite is congruent with the characteristics of CAM plants having great flexibility and plasticity in response to changes in environmental conditions. In addition, the formation of reproductive stem, viz. spike, was noticeably inhibited by a constant warm temperature, but induced by a fluctuating warm day and cool night condition. The relationship between the metabolic pool variation and spike induction of Phalaenopsis is also discussed.

  2. Early life antibiotic exposure affects pancreatic islet development and metabolic regulation

    PubMed Central

    Li, Jiaying; Yang, Kaiyuan; Ju, Tingting; Ho, Tracy; McKay, Catharine A.; Gao, Yanhua; Forget, Shay K.; Gartner, Stephanie R.; Field, Catherine J.; Chan, Catherine B.; Willing, Benjamin P.

    2017-01-01

    Childhood antibiotic exposure has been recently linked with increased risk of metabolic disease later in life. A better understanding of this association would potentially provide strategies to reduce the childhood chronic disease epidemic. Therefore, we explored the underlying mechanisms using a swine model that better mimics human infants than rodents, and demonstrated that early life antibiotic exposure affects glucose metabolism 5 weeks after antibiotic withdrawal, which was associated with changes in pancreatic development. Antibiotics exerted a transient impact on postnatal gut microbiota colonization and microbial metabolite production, yet changes in the expression of key genes involved in short-chain fatty acid signaling and pancreatic development were detected in later life. These findings suggest a programming effect of early life antibiotic exposure that merits further investigation. PMID:28150721

  3. Transient exposure to low levels of insecticide affects metabolic networks of honeybee larvae.

    PubMed

    Derecka, Kamila; Blythe, Martin J; Malla, Sunir; Genereux, Diane P; Guffanti, Alessandro; Pavan, Paolo; Moles, Anna; Snart, Charles; Ryder, Thomas; Ortori, Catharine A; Barrett, David A; Schuster, Eugene; Stöger, Reinhard

    2013-01-01

    The survival of a species depends on its capacity to adjust to changing environmental conditions, and new stressors. Such new, anthropogenic stressors include the neonicotinoid class of crop-protecting agents, which have been implicated in the population declines of pollinating insects, including honeybees (Apis mellifera). The low-dose effects of these compounds on larval development and physiological responses have remained largely unknown. Over a period of 15 days, we provided syrup tainted with low levels (2 µg/L(-1)) of the neonicotinoid insecticide imidacloprid to beehives located in the field. We measured transcript levels by RNA sequencing and established lipid profiles using liquid chromatography coupled with mass spectrometry from worker-bee larvae of imidacloprid-exposed (IE) and unexposed, control (C) hives. Within a catalogue of 300 differentially expressed transcripts in larvae from IE hives, we detect significant enrichment of genes functioning in lipid-carbohydrate-mitochondrial metabolic networks. Myc-involved transcriptional response to exposure of this neonicotinoid is indicated by overrepresentation of E-box elements in the promoter regions of genes with altered expression. RNA levels for a cluster of genes encoding detoxifying P450 enzymes are elevated, with coordinated downregulation of genes in glycolytic and sugar-metabolising pathways. Expression of the environmentally responsive Hsp90 gene is also reduced, suggesting diminished buffering and stability of the developmental program. The multifaceted, physiological response described here may be of importance to our general understanding of pollinator health. Muscles, for instance, work at high glycolytic rates and flight performance could be impacted should low levels of this evolutionarily novel stressor likewise induce downregulation of energy metabolising genes in adult pollinators.

  4. Transient Exposure to Low Levels of Insecticide Affects Metabolic Networks of Honeybee Larvae

    PubMed Central

    Derecka, Kamila; Blythe, Martin J.; Malla, Sunir; Genereux, Diane P.; Guffanti, Alessandro; Pavan, Paolo; Moles, Anna; Snart, Charles; Ryder, Thomas; Ortori, Catharine A.; Barrett, David A.; Schuster, Eugene; Stöger, Reinhard

    2013-01-01

    The survival of a species depends on its capacity to adjust to changing environmental conditions, and new stressors. Such new, anthropogenic stressors include the neonicotinoid class of crop-protecting agents, which have been implicated in the population declines of pollinating insects, including honeybees (Apis mellifera). The low-dose effects of these compounds on larval development and physiological responses have remained largely unknown. Over a period of 15 days, we provided syrup tainted with low levels (2 µg/L−1) of the neonicotinoid insecticide imidacloprid to beehives located in the field. We measured transcript levels by RNA sequencing and established lipid profiles using liquid chromatography coupled with mass spectrometry from worker-bee larvae of imidacloprid-exposed (IE) and unexposed, control (C) hives. Within a catalogue of 300 differentially expressed transcripts in larvae from IE hives, we detect significant enrichment of genes functioning in lipid-carbohydrate-mitochondrial metabolic networks. Myc-involved transcriptional response to exposure of this neonicotinoid is indicated by overrepresentation of E-box elements in the promoter regions of genes with altered expression. RNA levels for a cluster of genes encoding detoxifying P450 enzymes are elevated, with coordinated downregulation of genes in glycolytic and sugar-metabolising pathways. Expression of the environmentally responsive Hsp90 gene is also reduced, suggesting diminished buffering and stability of the developmental program. The multifaceted, physiological response described here may be of importance to our general understanding of pollinator health. Muscles, for instance, work at high glycolytic rates and flight performance could be impacted should low levels of this evolutionarily novel stressor likewise induce downregulation of energy metabolising genes in adult pollinators. PMID:23844170

  5. Dietary electrolyte balance affects growth performance, amylase activity and metabolic response in the meagre (Argyrosomus regius).

    PubMed

    Magnoni, Leonardo J; Salas-Leiton, Emilio; Peixoto, Maria-João; Pereira, Luis; Silva-Brito, Francisca; Fontinha, Filipa; Gonçalves, José F M; Wilson, Jonathan M; Schrama, Johan W; Ozório, Rodrigo O A

    2017-03-16

    Dietary ion content is known to alter the acid-base balance in freshwater fish. The current study investigated the metabolic impact of acid-base disturbances produced by differences in dietary electrolyte balance (DEB) in the meagre (Argyrosomus regius), an euryhaline species. Changes in fish performance, gastric chyme characteristics, pH and ion concentrations in the bloodstream, digestive enzyme activities and metabolic rates were analyzed in meagre fed ad libitum two experimental diets (DEB 200 or DEB 700mEq/kg) differing in the Na2CO3 content for 69days. Fish fed the DEB 200 diet had 60-66% better growth performance than the DEB 700 group. Meagre consuming the DEB 200 diet were 90-96% more efficient than fish fed the DEB 700 diet at allocating energy from feed into somatic growth. The pH values in blood were significantly lower in the DEB 700 group 2h after feeding when compared to DEB 200, indicating that acid-base balance in meagre was affected by electrolyte balance in diet. Osmolality, and Na(+) and K(+) concentrations in plasma did not vary with the dietary treatment. Gastric chyme in the DEB 700 group had higher pH values, dry matter, protein and energy contents, but lower lipid content than in the DEB 200 group. Twenty-four hours after feeding, amylase activity was higher in the gastrointestinal tract of DEB 700 group when compared to the DEB 200 group. DEB 700 group had lower routine metabolic (RMR) and standard metabolic (SMR) rates, indicating a decrease in maintenance energy expenditure 48h after feeding the alkaline diet. The current study demonstrates that feeding meagre with an alkaline diet not only causes acid-base imbalance, but also negatively affects digestion and possibly nutrient assimilation, resulting in decreased growth performance.

  6. Select nutrients, progesterone, and interferon tau affect conceptus metabolism and development.

    PubMed

    Bazer, Fuller W; Kim, Jingyoung; Song, Gwonhwa; Ka, Hakhyun; Tekwe, Carmen D; Wu, Guoyao

    2012-10-01

    Interferon tau (IFNT), a novel multifunctional type I interferon secreted by trophectoderm, is the pregnancy recognition signal in ruminants that also has antiviral, antiproliferative, and immunomodulatory bioactivities. IFNT, with progesterone, affects availability of the metabolic substrate in the uterine lumen by inducing expression of genes for transport of select nutrients into the uterine lumen that activate mammalian target of rapamycin (mTOR) cell signaling responsible for proliferation, migration, and protein synthesis by conceptus trophectoderm. As an immunomodulatory protein, IFNT induces an anti-inflammatory state affecting metabolic events that decrease adiposity and glutamine:fructose-6-phosphate amidotransferase 1 activity, while increasing insulin sensitivity, nitric oxide production by endothelial cells, and brown adipose tissue in rats. This short review focuses on effects of IFNT and progesterone affecting transport of select nutrients into the uterine lumen to stimulate mTOR cell signaling required for conceptus development, as well as effects of IFNT on the immune system and adiposity in rats with respect to its potential therapeutic value in reducing obesity.

  7. Aging of myelinating glial cells predominantly affects lipid metabolism and immune response pathways.

    PubMed

    Verdier, Valérie; Csárdi, Gábor; de Preux-Charles, Anne-Sophie; Médard, Jean-Jacques; Smit, August B; Verheijen, Mark H G; Bergmann, Sven; Chrast, Roman

    2012-05-01

    Both the central and the peripheral nervous systems are prone to multiple age-dependent neurological deficits, often attributed to still unknown alterations in the function of myelinating glia. To uncover the biological processes affected in glial cells by aging, we analyzed gene expression of the Schwann cell-rich mouse sciatic nerve at 17 time points throughout life, from day of birth until senescence. By combining these data with the gene expression data of myelin mouse mutants carrying deletions of either Pmp22, SCAP, or Lpin1, we found that the majority of age-related transcripts were also affected in myelin mutants (54.4%) and were regulated during PNS development (59.5%), indicating a high level of overlap in implicated molecular pathways. The expression profiles in aging copied the direction of transcriptional changes observed in neuropathy models; however, they had the opposite direction when compared with PNS development. The most significantly altered biological processes in aging involved the inflammatory/immune response and lipid metabolism. Interestingly, both these pathways were comparably changed in the aging optic nerve, suggesting that similar biological processes are affected in aging of glia-rich parts of the central and peripheral nervous systems. Our comprehensive comparison of gene expression in three distinct biological conditions including development, aging, and myelin disease thus revealed a previously unanticipated relationship among themselves and identified lipid metabolism and inflammatory/immune response pathways as potential therapeutical targets to prevent or delay so far incurable age-related and inherited forms of neuropathies.

  8. Evidence for efficacy of drugs affecting bone metabolism in preventing hip fracture.

    PubMed Central

    Kanis, J. A.; Johnell, O.; Gullberg, B.; Allander, E.; Dilşen, G.; Gennari, C.; Lopes Vaz, A. A.; Lyritis, G. P.; Mazzuoli, G.; Miravet, L.

    1992-01-01

    OBJECTIVE--To examine the effects of taking drugs affecting bone metabolism on the risk of hip fracture in women aged over 50 years. DESIGN--Retrospective, population based, case-control study by questionnaire. SETTING--14 centres in six countries in southern Europe. SUBJECTS--2086 women with hip fracture and 3532 control women matched for age. MAIN OUTCOME MEASURES--Number of drugs affecting bone metabolism taken and length taken for. RESULTS--Women taking drugs affecting bone metabolism had a significantly decreased risk of hip fracture. After adjustment for differences in other risk factors, the relative risk of hip fractures was 0.55 (95% confidence interval 0.31 to 0.85) in women taking oestrogens, 0.75 (0.60 to 0.94) in those taking calcium, and 0.69 (0.51 to 0.92) in those taking calcitonin. The fall in risk was not significant for anabolic steroids (0.6 (0.29 to 1.22)). Neither vitamin D nor fluorides were associated with a significant decrease in the risk of hip fracture. The effect on hip fracture risk increased significantly with increasing duration of exposure (risk ratio 0.8 (0.61 to 1.05) for less than median exposure v 0.66 (0.5 to 0.88) for greater than median exposure). Drugs were equally effective in older and younger women, with the exception of oestrogen. CONCLUSIONS--Oestrogen, calcium, and calcitonins significantly decrease the risk of hip fracture. Short term intervention late in the natural course of osteoporosis may have significant effects on the incidence of hip fracture. PMID:1463947

  9. Altered Phenylpropanoid Metabolism in the Maize Lc-Expressed Sweet Potato (Ipomoea batatas) Affects Storage Root Development.

    PubMed

    Wang, Hongxia; Yang, Jun; Zhang, Min; Fan, Weijuan; Firon, Nurit; Pattanaik, Sitakanta; Yuan, Ling; Zhang, Peng

    2016-01-04

    There is no direct evidence of the effect of lignin metabolism on early storage root development in sweet potato. In this study, we found that heterologous expression of the maize leaf color (Lc) gene in sweet potato increased anthocyanin pigment accumulation in the whole plant and resulted in reduced size with an increased length/width ratio, low yield and less starch content in the early storage roots. RT-PCR analysis revealed dramatic up-regulation of the genes involved in the lignin biosynthesis pathway in developing storage roots, leading to greater lignin content in the Lc transgenic lines, compared to the wild type. This was also evidenced by the enhanced lignification of vascular cells in the early storage roots. Furthermore, increased expression of the β-amylase gene in leaves and storage roots also accelerated starch degradation and increased the sugar use efficiency, providing more energy and carbohydrate sources for lignin biosynthesis in the Lc transgenic sweet potato. Lesser starch accumulation was observed in the developing storage roots at the initiation stage in the Lc plants. Our study provides experimental evidence of the basic carbohydrate metabolism underlying the development of storage roots, which is the transformation of lignin biosynthesis to starch biosynthesis.

  10. Altered Phenylpropanoid Metabolism in the Maize Lc-Expressed Sweet Potato (Ipomoea batatas) Affects Storage Root Development

    PubMed Central

    Wang, Hongxia; Yang, Jun; Zhang, Min; Fan, Weijuan; Firon, Nurit; Pattanaik, Sitakanta; Yuan, Ling; Zhang, Peng

    2016-01-01

    There is no direct evidence of the effect of lignin metabolism on early storage root development in sweet potato. In this study, we found that heterologous expression of the maize leaf color (Lc) gene in sweet potato increased anthocyanin pigment accumulation in the whole plant and resulted in reduced size with an increased length/width ratio, low yield and less starch content in the early storage roots. RT-PCR analysis revealed dramatic up-regulation of the genes involved in the lignin biosynthesis pathway in developing storage roots, leading to greater lignin content in the Lc transgenic lines, compared to the wild type. This was also evidenced by the enhanced lignification of vascular cells in the early storage roots. Furthermore, increased expression of the β-amylase gene in leaves and storage roots also accelerated starch degradation and increased the sugar use efficiency, providing more energy and carbohydrate sources for lignin biosynthesis in the Lc transgenic sweet potato. Lesser starch accumulation was observed in the developing storage roots at the initiation stage in the Lc plants. Our study provides experimental evidence of the basic carbohydrate metabolism underlying the development of storage roots, which is the transformation of lignin biosynthesis to starch biosynthesis. PMID:26727353

  11. Carbohydrate Counting and Diabetes

    MedlinePlus

    ... are the other main nutrients. Carbohydrates include sugars, starches, and fiber. Carbohydrate counting can help you control ... called starchy vegetables because they are high in starch. These vegetables have more carbohydrates per serving than ...

  12. Carboxylation of osteocalcin affects its association with metabolic parameters in healthy children.

    PubMed

    Prats-Puig, Anna; Mas-Parareda, Marta; Riera-Pérez, Elena; González-Forcadell, Dolors; Mier, Concepció; Mallol-Guisset, Montserrat; Díaz, Marta; Bassols, Judit; de Zegher, Francis; Ibáñez, Lourdes; López-Bermejo, Abel

    2010-03-01

    OBJECTIVE Osteocalcin (OC), a bone-derived protein, was recently shown to regulate metabolic pathways in mice. Undercarboxylated OC (ucOC), but not carboxylated OC (cOC), increases adiponectin and insulin secretion. It is unclear if carboxylation of OC affects its association with metabolic parameters in humans. RESEARCH DESIGN AND METHODS The associations between ucOC, cOC, total and high-molecular-weight (HMW) adiponectin, and insulin secretion (homeostasis model assessment [HOMA]-beta) were investigated in a population-based sample of healthy prepubertal children (n = 103; 49 boys and 54 girls). RESULTS Weight-dependent associations were observed between the different forms of OC and metabolic parameters. Higher cOC was related to lower HMW adiponectin (with a stronger association in leaner children; P < 0.001). Higher ucOC-to-cOC ratio was associated with higher HOMA-beta (P < 0.01) in leaner children and associated with higher HMW adiponectin (P < 0.001) in heavier children. CONCLUSIONS In a weight-dependent manner, cOC and the proportion of ucOC are differentially related to HMW adiponectin and insulin secretion in healthy children.

  13. Carboxylation of Osteocalcin Affects Its Association With Metabolic Parameters in Healthy Children

    PubMed Central

    Prats-Puig, Anna; Mas-Parareda, Marta; Riera-Pérez, Elena; González-Forcadell, Dolors; Mier, Concepció; Mallol-Guisset, Montserrat; Díaz, Marta; Bassols, Judit; de Zegher, Francis; Ibáñez, Lourdes; López-Bermejo, Abel

    2010-01-01

    OBJECTIVE Osteocalcin (OC), a bone-derived protein, was recently shown to regulate metabolic pathways in mice. Undercarboxylated OC (ucOC), but not carboxylated OC (cOC), increases adiponectin and insulin secretion. It is unclear if carboxylation of OC affects its association with metabolic parameters in humans. RESEARCH DESIGN AND METHODS The associations between ucOC, cOC, total and high-molecular-weight (HMW) adiponectin, and insulin secretion (homeostasis model assessment [HOMA]-β) were investigated in a population-based sample of healthy prepubertal children (n = 103; 49 boys and 54 girls). RESULTS Weight-dependent associations were observed between the different forms of OC and metabolic parameters. Higher cOC was related to lower HMW adiponectin (with a stronger association in leaner children; P < 0.001). Higher ucOC-to-cOC ratio was associated with higher HOMA-β (P < 0.01) in leaner children and associated with higher HMW adiponectin (P < 0.001) in heavier children. CONCLUSIONS In a weight-dependent manner, cOC and the proportion of ucOC are differentially related to HMW adiponectin and insulin secretion in healthy children. PMID:20009098

  14. Cannibalism Affects Core Metabolic Processes in Helicoverpa armigera Larvae—A 2D NMR Metabolomics Study

    PubMed Central

    Vergara, Fredd; Shino, Amiu; Kikuchi, Jun

    2016-01-01

    Cannibalism is known in many insect species, yet its impact on insect metabolism has not been investigated in detail. This study assessed the effects of cannibalism on the metabolism of fourth-instar larvae of the non-predatory insect Helicoverpa armigera (Lepidotera: Noctuidea). Two groups of larvae were analyzed: one group fed with fourth-instar larvae of H. armigera (cannibal), the other group fed with an artificial plant diet. Water-soluble small organic compounds present in the larvae were analyzed using two-dimensional nuclear magnetic resonance (NMR) and principal component analysis (PCA). Cannibalism negatively affected larval growth. PCA of NMR spectra showed that the metabolic profiles of cannibal and herbivore larvae were statistically different with monomeric sugars, fatty acid- and amino acid-related metabolites as the most variable compounds. Quantitation of 1H-13C HSQC (Heteronuclear Single Quantum Coherence) signals revealed that the concentrations of glucose, glucono-1,5-lactone, glycerol phosphate, glutamine, glycine, leucine, isoleucine, lysine, ornithine, proline, threonine and valine were higher in the herbivore larvae. PMID:27598144

  15. The fungicide triadimefon affects beer flavor and composition by influencing Saccharomyces cerevisiae metabolism.

    PubMed

    Kong, Zhiqiang; Li, Minmin; An, Jingjing; Chen, Jieying; Bao, Yuming; Francis, Frédéric; Dai, Xiaofeng

    2016-09-15

    Despite the fact that beer is produced on a large scale, the effects of pesticide residues on beer have been rarely investigated. In this study, we used micro-brewing settings to determine the effect of triadimefon on the growth of Saccharomyces cerevisiae and beer flavor. The yeast growth in medium was significantly inhibited (45%) at concentrations higher than 5 mg L(-1), reaching 80% and 100% inhibition at 10 mg L(-1) and 50 mg L(-1), respectively. There were significant differences in sensory quality between beer samples fermented with and without triadimefon based on data obtained with an electronic tongue and nose. Such an effect was most likely underlain by changes in yeast fermentation activity, including decreased utilization of maltotriose and most amino acids, reduced production of isobutyl and isoamyl alcohols, and increased ethyl acetate content in the fungicide treated samples. Furthermore, yeast metabolic profiling by phenotype microarray and UPLC/TOF-MS showed that triadimefon caused significant changes in the metabolism of glutathione, phenylalanine and sphingolipids, and in sterol biosynthesis. Thus, triadimefon negatively affects beer sensory qualities by influencing the metabolic activity of S. cerevisiae during fermentation, emphasizing the necessity of stricter control over fungicide residues in brewing by the food industry.

  16. L-carnosine affects the growth of Saccharomyces cerevisiae in a metabolism-dependent manner.

    PubMed

    Cartwright, Stephanie P; Bill, Roslyn M; Hipkiss, Alan R

    2012-01-01

    The dipeptide L-carnosine (β-alanyl-L-histidine) has been described as enigmatic: it inhibits growth of cancer cells but delays senescence in cultured human fibroblasts and extends the lifespan of male fruit flies. In an attempt to understand these observations, the effects of L-carnosine on the model eukaryote, Saccharomyces cerevisiae, were examined on account of its unique metabolic properties; S. cerevisiae can respire aerobically, but like some tumor cells, it can also exhibit a metabolism in which aerobic respiration is down regulated. L-Carnosine exhibited both inhibitory and stimulatory effects on yeast cells, dependent upon the carbon source in the growth medium. When yeast cells were not reliant on oxidative phosphorylation for energy generation (e.g. when grown on a fermentable carbon source such as 2% glucose), 10-30 mM L-carnosine slowed growth rates in a dose-dependent manner and increased cell death by up to 17%. In contrast, in media containing a non-fermentable carbon source in which yeast are dependent on aerobic respiration (e.g. 2% glycerol), L-carnosine did not provoke cell death. This latter observation was confirmed in the respiratory yeast, Pichia pastoris. Moreover, when deletion strains in the yeast nutrient-sensing pathway were treated with L-carnosine, the cells showed resistance to its inhibitory effects. These findings suggest that L-carnosine affects cells in a metabolism-dependent manner and provide a rationale for its effects on different cell types.

  17. The fungicide triadimefon affects beer flavor and composition by influencing Saccharomyces cerevisiae metabolism

    NASA Astrophysics Data System (ADS)

    Kong, Zhiqiang; Li, Minmin; An, Jingjing; Chen, Jieying; Bao, Yuming; Francis, Frédéric; Dai, Xiaofeng

    2016-09-01

    Despite the fact that beer is produced on a large scale, the effects of pesticide residues on beer have been rarely investigated. In this study, we used micro-brewing settings to determine the effect of triadimefon on the growth of Saccharomyces cerevisiae and beer flavor. The yeast growth in medium was significantly inhibited (45%) at concentrations higher than 5 mg L‑1, reaching 80% and 100% inhibition at 10 mg L‑1 and 50 mg L‑1, respectively. There were significant differences in sensory quality between beer samples fermented with and without triadimefon based on data obtained with an electronic tongue and nose. Such an effect was most likely underlain by changes in yeast fermentation activity, including decreased utilization of maltotriose and most amino acids, reduced production of isobutyl and isoamyl alcohols, and increased ethyl acetate content in the fungicide treated samples. Furthermore, yeast metabolic profiling by phenotype microarray and UPLC/TOF-MS showed that triadimefon caused significant changes in the metabolism of glutathione, phenylalanine and sphingolipids, and in sterol biosynthesis. Thus, triadimefon negatively affects beer sensory qualities by influencing the metabolic activity of S. cerevisiae during fermentation, emphasizing the necessity of stricter control over fungicide residues in brewing by the food industry.

  18. Central Metabolic Responses to Ozone and Herbivory Affect Photosynthesis and Stomatal Closure1[OPEN

    PubMed Central

    Khaling, Eliezer; Lassueur, Steve

    2016-01-01

    Plants have evolved adaptive mechanisms that allow them to tolerate a continuous range of abiotic and biotic stressors. Tropospheric ozone (O3), a global anthropogenic pollutant, directly affects living organisms and ecosystems, including plant-herbivore interactions. In this study, we investigate the stress responses of Brassica nigra (wild black mustard) exposed consecutively to O3 and the specialist herbivore Pieris brassicae. Transcriptomics and metabolomics data were evaluated using multivariate, correlation, and network analyses for the O3 and herbivory responses. O3 stress symptoms resembled those of senescence and phosphate starvation, while a sequential shift from O3 to herbivory induced characteristic plant defense responses, including