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Sample records for affect protein metabolism

  1. Evidence that high pCO2 affects protein metabolism in tropical reef corals.

    PubMed

    Edmunds, Peter J; Wall, Christopher B

    2014-08-01

    Early life stages of the coral Seriatopora caliendrum were used to test the hypothesis that the depression of dark respiration in coral recruits by high pCO2 is caused by perturbed protein metabolism. First, the contribution of protein anabolism to respiratory costs under high pCO2 was evaluated by measuring the aerobic respiration of S. caliendrum recruits with and without the protein synthesis inhibitor emetine following 1 to 4 days at 45 Pa versus 77 Pa pCO2. Second, protein catabolism under high pCO2 was evaluated by measuring the flux of ammonium (NH4 (+)) from juvenile colonies of S. caliendrum incubated in darkness at 47 Pa and 90 Pa pCO2. Two days after settlement, respiration of recruits was affected by an interaction between emetine and pCO2, with emetine reducing respiration 63% at 45 Pa pCO2 and 27% at 77 Pa pCO2. The interaction disappeared 5 days after settlement, when respiration was reduced 27% by emetine under both pCO2 conditions. These findings suggest that protein anabolism accounted for a large proportion of metabolic costs in coral recruits and was affected by high pCO2, with consequences detected in aerobic respiration. Juvenile S. caliendrum showed net uptake of NH4 (+) at 45 Pa pCO2 but net release of NH4 (+) at 90 Pa pCO2, indicating that protein catabolism, NH4 (+) recycling, or both were affected by high pCO2. Together, these results are consistent with the hypothesis that high pCO2 affects protein metabolism in corals.

  2. Hepatitis B virus (HBV) X protein-mediated regulation of hepatocyte metabolic pathways affects viral replication.

    PubMed

    Bagga, Sumedha; Rawat, Siddhartha; Ajenjo, Marcia; Bouchard, Michael J

    2016-11-01

    Chronic HBV infection is a risk factor for hepatocellular carcinoma (HCC). The HBV HBx protein stimulates HBV replication and likely influences the development of HBV-associated HCC. Whether HBx affects regulators of metabolism in normal hepatocytes has not been addressed. We used an ex vivo, cultured primary rat hepatocyte system to assess the interplay between HBV replication and mechanistic target of rapamycin complex 1 (mTORC1) signaling. HBx activated mTORC1 signaling; however, inhibition of mTORC1 enhanced HBV replication. HBx also decreased ATP levels and activated the energy-sensing factor AMP-activated protein kinase (AMPK). Inhibition of AMPK decreased HBV replication. Inhibition of AMPK activates mTORC1, and we showed that activated mTORC1 is one factor that reduces HBV replication when AMPK is inhibited. HBx activation of both AMPK and mTORC1 suggests that these activities could provide a balancing mechanism to facilitate persistent HBV replication. HBx activation of mTORC1 and AMPK could also influence HCC development.

  3. Protein acetylation affects acetate metabolism, motility and acid stress response in Escherichia coli

    PubMed Central

    Castaño-Cerezo, Sara; Bernal, Vicente; Post, Harm; Fuhrer, Tobias; Cappadona, Salvatore; Sánchez-Díaz, Nerea C; Sauer, Uwe; Heck, Albert JR; Altelaar, AF Maarten; Cánovas, Manuel

    2014-01-01

    Although protein acetylation is widely observed, it has been associated with few specific regulatory functions making it poorly understood. To interrogate its functionality, we analyzed the acetylome in Escherichia coli knockout mutants of cobB, the only known sirtuin-like deacetylase, and patZ, the best-known protein acetyltransferase. For four growth conditions, more than 2,000 unique acetylated peptides, belonging to 809 proteins, were identified and differentially quantified. Nearly 65% of these proteins are related to metabolism. The global activity of CobB contributes to the deacetylation of a large number of substrates and has a major impact on physiology. Apart from the regulation of acetyl-CoA synthetase, we found that CobB-controlled acetylation of isocitrate lyase contributes to the fine-tuning of the glyoxylate shunt. Acetylation of the transcription factor RcsB prevents DNA binding, activating flagella biosynthesis and motility, and increases acid stress susceptibility. Surprisingly, deletion of patZ increased acetylation in acetate cultures, which suggests that it regulates the levels of acetylating agents. The results presented offer new insights into functional roles of protein acetylation in metabolic fitness and global cell regulation. PMID:25518064

  4. Global proteomic analysis of protein acetylation affecting metabolic regulation in Daphnia pulex.

    PubMed

    Kwon, Oh Kwang; Sim, Juhee; Kim, Sun Ju; Oh, Hye Ryeung; Nam, Doo Hyun; Lee, Sangkyu

    2016-02-01

    Daphnia (Daphnia pulex) is a small planktonic crustacean and a key constituent of aquatic ecosystems. It is generally used as a model organism to study environmental toxic problems. In the past decade, genomic and proteomic datasets of Daphnia have been developed. The proteomic dataset allows for the investigation of toxicological effects in the context of "Daphnia proteomics," resulting in greater insights for toxicological research. To exploit Daphnia for ecotoxicological research, information on the post-translational modification (PTM) of proteins is necessary, as this is a critical regulator of biological processes. Acetylation of lysine (Kac) is a reversible and highly regulated PTM that is associated with diverse biological functions. However, a comprehensive description of Kac in Daphnia is not yet available. To understand the cellular distribution of lysine acetylation in Daphnia, we identified 98 acetylation sites in 65 proteins by immunoprecipitation using an anti-acetyllysine antibody and a liquid chromatography system supported by mass spectroscopy. We identified 28 acetylated sites related to metabolic proteins and six acetylated enzymes associated with the TCA cycle in Daphnia. From GO and KEGG enrichment analyses, we showed that Kac in D. pulex is highly enriched in proteins associated with metabolic processes. Our data provide the first global analysis of Kac in D. pulex and is an important resource for the functional analysis of Kac in this organism. PMID:26700148

  5. Cocoa and Whey Protein Differentially Affect Markers of Lipid and Glucose Metabolism and Satiety.

    PubMed

    Campbell, Caroline L; Foegeding, E Allen; Harris, G Keith

    2016-03-01

    Food formulation with bioactive ingredients is a potential strategy to promote satiety and weight management. Whey proteins are high in leucine and are shown to decrease hunger ratings and increase satiety hormone levels; cocoa polyphenolics moderate glucose levels and slow digestion. This study examined the effects of cocoa and whey proteins on lipid and glucose metabolism and satiety in vitro and in a clinical trial. In vitro, 3T3-L1 preadipocytes were treated with 0.5-100 μg/mL cocoa polyphenolic extract (CPE) and/or 1-15 mM leucine (Leu) and assayed for lipid accumulation and leptin production. In vivo, a 6-week clinical trial consisted of nine panelists (age: 22.6 ± 1.7; BMI: 22.3 ± 2.1) consuming chocolate-protein beverages once per week, including placebo, whey protein isolate (WPI), low polyphenolic cocoa (LP), high polyphenolic cocoa (HP), LP-WPI, and HP-WPI. Measurements included blood glucose and adiponectin levels, and hunger ratings at baseline and 0.5-4.0 h following beverage consumption. At levels of 50 and 100 μg/mL, CPE significantly inhibited preadipocyte lipid accumulation by 35% and 50%, respectively, and by 22% and 36% when combined with 15 mM Leu. Leu treatment increased adipocyte leptin production by 26-37%. In the clinical trial, all beverages significantly moderated blood glucose levels 30 min postconsumption. WPI beverages elicited lowest peak glucose levels and HP levels were significantly lower than LP. The WPI and HP beverage treatments significantly increased adiponectin levels, but elicited no significant changes in hunger ratings. These trends suggest that combinations of WPI and cocoa polyphenols may improve markers of metabolic syndrome and satiety. PMID:26987021

  6. Ecdysteroids affect in vivo protein metabolism of the flight muscle of the tobacco hornworm (Manduca sexta)

    NASA Technical Reports Server (NTRS)

    Tischler, M. E.; Wu, M.; Cook, P.; Hodsden, S.

    1990-01-01

    Ecdysteroid growth promotion of the dorsolongitudinal flight muscle of Manduca sexta was studied by measuring in vivo protein metabolism using both "flooding-dose" and "non-carrier" techniques. These procedures differ in that the former method includes injection of non-labelled phenylalanine (30 micromoles/insect) together with the [3H]amino acid. Injected radioactivity plateaued in the haemolymph within 7 min. With the flooding-dose method, haemolymph and intramuscular specific radioactivities were similar between 15 min and 2 h. Incorporation of [3H]phenylalanine into muscle protein was linear with either method between 30 and 120 min. Fractional rates (%/12 h) of synthesis with the flooding-dose technique were best measured after 1 h because of the initial delay in radioactivity equilibration. Estimation of body phenylalanine turnover with the non-carrier method showed 24-53%/h which was negligible with the flooding-dose method. Since the two methods yielded similar rates of protein synthesis, the large injection of non-labelled amino acid did not alter the rate of synthesis. Because the flooding-dose technique requires only a single time point measurement, it is the preferred method. The decline and eventual cessation of flight-muscle growth was mostly a consequence of declining protein synthesis though degradation increased between 76-86 h before eclosion and was relatively rapid. This decline in muscle growth could be prevented by treating pupae with 20-hydroxyecdysone (10 micrograms/insect). Protein accretion was promoted by a decline of up to 80% in protein breakdown, which was offset in part by a concurrent though much smaller decrease in protein synthesis. Therefore, ecdysteroids may increase flight-muscle growth by inhibiting proteolysis.

  7. In Absence of the Cellular Prion Protein, Alterations in Copper Metabolism and Copper-Dependent Oxidase Activity Affect Iron Distribution

    PubMed Central

    Gasperini, Lisa; Meneghetti, Elisa; Legname, Giuseppe; Benetti, Federico

    2016-01-01

    Essential elements as copper and iron modulate a wide range of physiological functions. Their metabolism is strictly regulated by cellular pathways, since dysregulation of metal homeostasis is responsible for many detrimental effects. Neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and prion diseases are characterized by alterations of metal ions. These neurodegenerative maladies involve proteins that bind metals and mediate their metabolism through not well-defined mechanisms. Prion protein, for instance, interacts with divalent cations via multiple metal-binding sites and it modulates several metal-dependent physiological functions, such as S-nitrosylation of NMDA receptors. In this work we focused on the effect of prion protein absence on copper and iron metabolism during development and adulthood. In particular, we investigated copper and iron functional values in serum and several organs such as liver, spleen, total brain and isolated hippocampus. Our results show that iron content is diminished in prion protein-null mouse serum, while it accumulates in liver and spleen. Our data suggest that these alterations can be due to impairments in copper-dependent cerulopalsmin activity which is known to affect iron mobilization. In prion protein-null mouse total brain and hippocampus, metal ion content shows a fluctuating trend, suggesting the presence of homeostatic compensatory mechanisms. However, copper and iron functional values are likely altered also in these two organs, as indicated by the modulation of metal-binding protein expression levels. Altogether, these results reveal that the absence of the cellular prion protein impairs copper metabolism and copper-dependent oxidase activity, with ensuing alteration of iron mobilization from cellular storage compartments. PMID:27729845

  8. Continual feeding of two types of microalgal biomass affected protein digestion and metabolism in laying hens.

    PubMed

    Ekmay, R D; Chou, K; Magnuson, A; Lei, X G

    2015-01-01

    A 14-wk study was conducted to determine the nutritional efficacy and ssmetabolic impact of 2 types of microalgal biomass as alternative protein sources in laying hen diets. Shaver hens (total = 150 and 26 wk old) were fed 1 of 5 diets: a control or a defatted green microalgal biomass (DG; Desmodesmus spp.) at 25% and a full-fatted diatom biomass (FD; Staurosira spp.) at 11.7% inclusion with or without protease. This experiment consisted of 5 replicates per treatment and each replicate contained 6 hens individually reared in cages (1 hen for biochemical data/replicate). Despite decreased ADFI (P = 0.03), hens fed DG or FD had final BW, overall hen-day egg production, and egg quality similar to the controls. Feeding DG or FD did not alter plasma concentrations of insulin, glutamine, and uric acid or alkaline phosphatase activity at wk 8 or 14 but decreased plasma 3-methyhistine concentrations (P = 0.03) and tartrate-resistant acid phosphatase (TRAP) activities (P < 0.001) at wk 14 and improved (P = 0.002) ileal total AA digestibility. Although DG or FD exhibited moderate effects on intestinal brush border protease activities and mRNA levels of duodenal transporters Pept1, Lat1, and Cat1, both substantially enhanced (P < 0.05) phosphorylation of hepatic protein synthesis key regulator S6 ribosomal protein (S6) and the ratio of phospho-S6 to S6 in the liver of hens. However, DG and FD manifested with different impacts on weights of egg and egg albumen, proteolytic activity of jejunal digesta, plasma TRAP activity, ileal total AA digestibility, and several intestinal genes and hepatic proteins. Supplemental protease in the DG and FD diets produced mixed effects on a number of measures. In conclusion, our findings revealed the feasibility of including greater levels of microalgal biomass as a source of feed protein for laying hens and a novel potential of the biomass in improving dietary protein digestion and body protein metabolism than previously perceived. PMID

  9. Continual feeding of two types of microalgal biomass affected protein digestion and metabolism in laying hens.

    PubMed

    Ekmay, R D; Chou, K; Magnuson, A; Lei, X G

    2015-01-01

    A 14-wk study was conducted to determine the nutritional efficacy and ssmetabolic impact of 2 types of microalgal biomass as alternative protein sources in laying hen diets. Shaver hens (total = 150 and 26 wk old) were fed 1 of 5 diets: a control or a defatted green microalgal biomass (DG; Desmodesmus spp.) at 25% and a full-fatted diatom biomass (FD; Staurosira spp.) at 11.7% inclusion with or without protease. This experiment consisted of 5 replicates per treatment and each replicate contained 6 hens individually reared in cages (1 hen for biochemical data/replicate). Despite decreased ADFI (P = 0.03), hens fed DG or FD had final BW, overall hen-day egg production, and egg quality similar to the controls. Feeding DG or FD did not alter plasma concentrations of insulin, glutamine, and uric acid or alkaline phosphatase activity at wk 8 or 14 but decreased plasma 3-methyhistine concentrations (P = 0.03) and tartrate-resistant acid phosphatase (TRAP) activities (P < 0.001) at wk 14 and improved (P = 0.002) ileal total AA digestibility. Although DG or FD exhibited moderate effects on intestinal brush border protease activities and mRNA levels of duodenal transporters Pept1, Lat1, and Cat1, both substantially enhanced (P < 0.05) phosphorylation of hepatic protein synthesis key regulator S6 ribosomal protein (S6) and the ratio of phospho-S6 to S6 in the liver of hens. However, DG and FD manifested with different impacts on weights of egg and egg albumen, proteolytic activity of jejunal digesta, plasma TRAP activity, ileal total AA digestibility, and several intestinal genes and hepatic proteins. Supplemental protease in the DG and FD diets produced mixed effects on a number of measures. In conclusion, our findings revealed the feasibility of including greater levels of microalgal biomass as a source of feed protein for laying hens and a novel potential of the biomass in improving dietary protein digestion and body protein metabolism than previously perceived.

  10. A Small Protein Associated with Fungal Energy Metabolism Affects the Virulence of Cryptococcus neoformans in Mammals.

    PubMed

    McClelland, Erin E; Ramagopal, Udupi A; Rivera, Johanna; Cox, James; Nakouzi, Antonio; Prabu, Moses M; Almo, Steven C; Casadevall, Arturo

    2016-09-01

    The pathogenic yeast Cryptococcus neoformans causes cryptococcosis, a life-threatening fungal disease. C. neoformans has multiple virulence mechanisms that are non-host specific, induce damage and interfere with immune clearance. Microarray analysis of C. neoformans strains serially passaged in mice associated a small gene (CNAG_02591) with virulence. This gene, hereafter identified as HVA1 (hypervirulence-associated protein 1), encodes a protein that has homologs of unknown function in plant and animal fungi, consistent with a conserved mechanism. Expression of HVA1 was negatively correlated with virulence and was reduced in vitro and in vivo in both mouse- and Galleria-passaged strains of C. neoformans. Phenotypic analysis in hva1Δ and hva1Δ+HVA1 strains revealed no significant differences in established virulence factors. Mice infected intravenously with the hva1Δ strain had higher fungal burden in the spleen and brain, but lower fungal burden in the lungs, and died faster than mice infected with H99W or the hva1Δ+HVA1 strain. Metabolomics analysis demonstrated a general increase in all amino acids measured in the disrupted strain and a block in the TCA cycle at isocitrate dehydrogenase, possibly due to alterations in the nicotinamide cofactor pool. Macrophage fungal burden experiments recapitulated the mouse hypervirulent phenotype of the hva1Δ strain only in the presence of exogenous NADPH. The crystal structure of the Hva1 protein was solved, and a comparison of structurally similar proteins correlated with the metabolomics data and potential interactions with NADPH. We report a new gene that modulates virulence through a mechanism associated with changes in fungal metabolism. PMID:27583447

  11. A Small Protein Associated with Fungal Energy Metabolism Affects the Virulence of Cryptococcus neoformans in Mammals

    PubMed Central

    Cox, James; Nakouzi, Antonio; Prabu, Moses M.; Almo, Steven C.

    2016-01-01

    The pathogenic yeast Cryptococcus neoformans causes cryptococcosis, a life-threatening fungal disease. C. neoformans has multiple virulence mechanisms that are non-host specific, induce damage and interfere with immune clearance. Microarray analysis of C. neoformans strains serially passaged in mice associated a small gene (CNAG_02591) with virulence. This gene, hereafter identified as HVA1 (hypervirulence-associated protein 1), encodes a protein that has homologs of unknown function in plant and animal fungi, consistent with a conserved mechanism. Expression of HVA1 was negatively correlated with virulence and was reduced in vitro and in vivo in both mouse- and Galleria-passaged strains of C. neoformans. Phenotypic analysis in hva1Δ and hva1Δ+HVA1 strains revealed no significant differences in established virulence factors. Mice infected intravenously with the hva1Δ strain had higher fungal burden in the spleen and brain, but lower fungal burden in the lungs, and died faster than mice infected with H99W or the hva1Δ+HVA1 strain. Metabolomics analysis demonstrated a general increase in all amino acids measured in the disrupted strain and a block in the TCA cycle at isocitrate dehydrogenase, possibly due to alterations in the nicotinamide cofactor pool. Macrophage fungal burden experiments recapitulated the mouse hypervirulent phenotype of the hva1Δ strain only in the presence of exogenous NADPH. The crystal structure of the Hva1 protein was solved, and a comparison of structurally similar proteins correlated with the metabolomics data and potential interactions with NADPH. We report a new gene that modulates virulence through a mechanism associated with changes in fungal metabolism. PMID:27583447

  12. Arginine depletion by arginine deiminase does not affect whole protein metabolism or muscle fractional protein synthesis rate in mice.

    PubMed

    Marini, Juan C; Didelija, Inka Cajo

    2015-01-01

    Due to the absolute need for arginine that certain cancer cells have, arginine depletion is a therapy in clinical trials to treat several types of cancers. Arginine is an amino acids utilized not only as a precursor for other important molecules, but also for protein synthesis. Because arginine depletion can potentially exacerbate the progressive loss of body weight, and especially lean body mass, in cancer patients we determined the effect of arginine depletion by pegylated arginine deiminase (ADI-PEG 20) on whole body protein synthesis and fractional protein synthesis rate in multiple tissues of mice. ADI-PEG 20 successfully depleted circulating arginine (<1 μmol/L), and increased citrulline concentration more than tenfold. Body weight and body composition, however, were not affected by ADI-PEG 20. Despite the depletion of arginine, whole body protein synthesis and breakdown were maintained in the ADI-PEG 20 treated mice. The fractional protein synthesis rate of muscle was also not affected by arginine depletion. Most tissues (liver, kidney, spleen, heart, lungs, stomach, small and large intestine, pancreas) were able to maintain their fractional protein synthesis rate; however, the fractional protein synthesis rate of brain, thymus and testicles was reduced due to the ADI-PEG 20 treatment. Furthermore, these results were confirmed by the incorporation of ureido [14C]citrulline, which indicate the local conversion into arginine, into protein. In conclusion, the intracellular recycling pathway of citrulline is able to provide enough arginine to maintain protein synthesis rate and prevent the loss of lean body mass and body weight.

  13. Metformin revisited: Does this regulator of AMP-activated protein kinase secondarily affect bone metabolism and prevent diabetic osteopathy.

    PubMed

    McCarthy, Antonio Desmond; Cortizo, Ana María; Sedlinsky, Claudia

    2016-03-25

    Patients with long-term type 1 and type 2 diabetes mellitus (DM) can develop skeletal complications or "diabetic osteopathy". These include osteopenia, osteoporosis and an increased incidence of low-stress fractures. In this context, it is important to evaluate whether current anti-diabetic treatments can secondarily affect bone metabolism. Adenosine monophosphate-activated protein kinase (AMPK) modulates multiple metabolic pathways and acts as a sensor of the cellular energy status; recent evidence suggests a critical role for AMPK in bone homeostasis. In addition, AMPK activation is believed to mediate most clinical effects of the insulin-sensitizer metformin. Over the past decade, several research groups have investigated the effects of metformin on bone, providing a considerable body of pre-clinical (in vitro, ex vivo and in vivo) as well as clinical evidence for an anabolic action of metformin on bone. However, two caveats should be kept in mind when considering metformin treatment for a patient with type 2 DM at risk for diabetic osteopathy. In the first place, metformin should probably not be considered an anti-osteoporotic drug; it is an insulin sensitizer with proven macrovascular benefits that can secondarily improve bone metabolism in the context of DM. Secondly, we are still awaiting the results of randomized placebo-controlled studies in humans that evaluate the effects of metformin on bone metabolism as a primary endpoint.

  14. Metformin revisited: Does this regulator of AMP-activated protein kinase secondarily affect bone metabolism and prevent diabetic osteopathy

    PubMed Central

    McCarthy, Antonio Desmond; Cortizo, Ana María; Sedlinsky, Claudia

    2016-01-01

    Patients with long-term type 1 and type 2 diabetes mellitus (DM) can develop skeletal complications or “diabetic osteopathy”. These include osteopenia, osteoporosis and an increased incidence of low-stress fractures. In this context, it is important to evaluate whether current anti-diabetic treatments can secondarily affect bone metabolism. Adenosine monophosphate-activated protein kinase (AMPK) modulates multiple metabolic pathways and acts as a sensor of the cellular energy status; recent evidence suggests a critical role for AMPK in bone homeostasis. In addition, AMPK activation is believed to mediate most clinical effects of the insulin-sensitizer metformin. Over the past decade, several research groups have investigated the effects of metformin on bone, providing a considerable body of pre-clinical (in vitro, ex vivo and in vivo) as well as clinical evidence for an anabolic action of metformin on bone. However, two caveats should be kept in mind when considering metformin treatment for a patient with type 2 DM at risk for diabetic osteopathy. In the first place, metformin should probably not be considered an anti-osteoporotic drug; it is an insulin sensitizer with proven macrovascular benefits that can secondarily improve bone metabolism in the context of DM. Secondly, we are still awaiting the results of randomized placebo-controlled studies in humans that evaluate the effects of metformin on bone metabolism as a primary endpoint. PMID:27022443

  15. Milk protein yield and mammary metabolism are affected by phenylalanine deficiency but not by threonine or tryptophan deficiency.

    PubMed

    Doepel, L; Hewage, I I; Lapierre, H

    2016-04-01

    Efficient milk protein synthesis requires that the essential AA be presented to the mammary gland in the right amount and proportion to maximize protein synthesis and minimize losses. This study investigated the effects of individual AA deficiencies on cow productivity, mammary metabolism, and glucose whole-body rate of appearance. Five Holstein cows were used in a 5 × 5 Latin square design trial with 10-d periods. Treatments were abomasal infusions of (1) water (CTL); (2) complete AA mixture (TAA); (3) TAA without Phe (No-Phe); (4) TAA without Thr (No-Thr); and (5) TAA without Trp (No-Trp). Each treatment was compared with TAA. Treatment did not affect milk, fat, or lactose yields. Arterial concentrations of Phe, Thr, and Trp decreased with their respective deletions by 60, 76, and 69%. In response to the decreased arterial supply of the deleted AA, mammary plasma flow significantly increased by 55% with No-Thr but did not increase with No-Phe or No-Trp. Mammary uptake of Phe was reduced by No-Phe, accompanied by a reduced milk protein yield; uptakes of Thr and Trp were not affected by their respective deletions, and milk protein yield did not decrease with these treatments. Deletion of Phe tended to reduce its mammary uptake relative to milk output (U:O), accompanied by an increased U:O of Tyr, but deletion of Thr and Trp did not affect the U:O of the corresponding AA. Plasma urea-N concentration was lower with CTL and tended to be higher with No-Phe. Arterial concentrations and mammary uptake of acetate, β-hydroxybutyrate, glucose, and lactate were unaffected by treatment. Treatment had no effect on glucose rate of appearance at the whole-body level. Lactose output as a percentage of glucose whole-body rate of appearance was not affected by treatment. Overall, the study indicated that a deficiency of Phe negatively affected productivity and mammary metabolism but that a deficiency of Thr or Trp did not.

  16. Dietary protein intake affects expression of genes for lipid metabolism in porcine skeletal muscle in a genotype-dependent manner.

    PubMed

    Liu, Yingying; Li, Fengna; He, Lingyun; Tan, Bie; Deng, Jinping; Kong, Xiangfeng; Li, Yinghui; Geng, Meimei; Yin, Yulong; Wu, Guoyao

    2015-04-14

    Skeletal muscle is a major site for the oxidation of fatty acids (FA) in mammals, including humans. Using a swine model, we tested the hypothesis that dietary protein intake regulates the expression of key genes for lipid metabolism in skeletal muscle. A total of ninety-six barrows (forty-eight pure-bred Bama mini-pigs (fatty genotype) and forty-eight Landrace pigs (lean genotype)) were fed from 5 weeks of age to market weight. Pigs of fatty or lean genotype were randomly assigned to one of two dietary treatments (low- or adequate-protein diet), with twenty-four individually fed pigs per treatment. Our data showed that dietary protein levels affected the expression of genes involved in the anabolism and catabolism of lipids in the longissimus dorsi and biceps femoris muscles in a genotype-dependent manner. Specifically, Bama mini-pigs had more intramuscular fat, SFA and MUFA, as well as elevated mRNA expression levels of lipogenic genes, compared with Landrace pigs. In contrast, Bama mini-pigs had lower mRNA expression levels of lipolytic genes than Landrace pigs fed an adequate-protein diet in the growing phase. These data are consistent with higher white-fat deposition in Bama mini-pigs than in Landrace pigs. In conclusion, adequate provision of dietary protein (amino acids) plays an important role in regulating the expression of key lipogenic genes, and the growth of white adipose tissue, in a genotype- and tissue-specific manner. These findings have important implications for developing novel dietary strategies in pig production.

  17. Arginine depletion by arginine deiminase does not affect whole protein metabolism or muscle fractional protein synthesis rate in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the absolute need for arginine that certain cancer cells have, arginine depletion is a therapy in clinical trials to treat several types of cancers. Arginine is an amino acids utilized not only as a precursor for other important molecules, but also for protein synthesis. Because arginine depl...

  18. Muscle or liver-specific Sirt3 deficiency induces hyperacetylation of mitochondrial proteins without affecting global metabolic homeostasis.

    PubMed

    Fernandez-Marcos, Pablo J; Jeninga, Ellen H; Canto, Carles; Harach, Taoufiq; de Boer, Vincent C J; Andreux, Penelope; Moullan, Norman; Pirinen, Eija; Yamamoto, Hiroyasu; Houten, Sander M; Schoonjans, Kristina; Auwerx, Johan

    2012-01-01

    Sirt3 is a mitochondrial sirtuin, predominantly expressed in highly metabolic tissues. Germline ablation of Sirt3 has major metabolic consequences, including increased susceptibility to metabolic damage and oxidative stress after high fat feeding. In order to determine the contribution of liver and skeletal muscle to these phenotypes, we generated muscle-specific Sirt3 (Sirt3(skm-/-)) and liver-specific Sirt3 (Sirt3(hep-/-)) knock-out mice. Despite a marked global hyperacetylation of mitochondrial proteins, Sirt3(skm-/-) and Sirt3(hep-/-) mice did not manifest any overt metabolic phenotype under either chow or high fat diet conditions. Similarly, there was no evidence for increased oxidative stress in muscle or liver when Sirt3 was ablated in a tissue-specific manner. These observations suggest that the mitochondrial hyperacetylation induced by Sirt3-deletion in a tissue specific manner is not necessarily linked to mitochondrial dysfunction and does not recapitulate the metabolic abnormalities observed in the germline Sirt3 knock-out mice. PMID:22645641

  19. Fish protein hydrolysates affect cholesterol metabolism in rats fed non-cholesterol and high-cholesterol diets.

    PubMed

    Hosomi, Ryota; Fukunaga, Kenji; Arai, Hirofumi; Kanda, Seiji; Nishiyama, Toshimasa; Yoshida, Munehiro

    2012-03-01

    Fish consumption is well known to provide health benefits in both experimental animals and human subjects. Numerous studies have demonstrated the beneficial effects of various protein hydrolysates on lipid metabolism. In this context, this study examined the effect of fish protein hydrolysates (FPH) on cholesterol metabolism compared with the effect of casein. FPHs were prepared from Alaska pollock meat using papain as a protease. Male Wistar rats were divided into the following four dietary groups of seven rats each: either casein (20%) or FPH (10%) + casein (10%), with or without 0.5% cholesterol and 0.1% sodium cholate. Serum and liver lipid levels, fecal cholesterol and bile acid excretions, and the hepatic expression of genes encoding proteins involved in cholesterol homeostasis were examined. In rats fed the FPH diets compared with casein diets with or without cholesterol and sodium cholate, the indexes of cholesterol metabolism-namely, serum cholesterol, triglyceride, and low-density lipoprotein-cholesterol levels-were significantly lower, whereas fecal cholesterol and bile acid excretions were higher. Rats fed the FPH diets compared with casein with cholesterol exhibited a lower liver cholesterol level via an increased liver cholesterol 7α-hydroxylase (CYP7A1) expression level. This study demonstrates that the intake of FPH has hypocholesterolemic effects through the enhancement of fecal cholesterol and bile acid excretions and CYP7A1 expression levels. Therefore, fish peptides prepared by papain digestion might provide health benefits by decreasing the cholesterol content in the blood, which would contribute to the prevention of circulatory system diseases such as arteriosclerosis. PMID:22181072

  20. Low and high dietary protein:carbohydrate ratios during pregnancy affect materno-fetal glucose metabolism in pigs.

    PubMed

    Metges, Cornelia C; Görs, Solvig; Lang, Iris S; Hammon, Harald M; Brüssow, Klaus-Peter; Weitzel, Joachim M; Nürnberg, Gerd; Rehfeldt, Charlotte; Otten, Winfried

    2014-02-01

    Inadequate dietary protein during pregnancy causes intrauterine growth retardation. Whether this is related to altered maternal and fetal glucose metabolism was examined in pregnant sows comparing a high-protein:low-carbohydrate diet (HP-LC; 30% protein, 39% carbohydrates) with a moderately low-protein:high-carbohydrate diet (LP-HC; 6.5% protein, 68% carbohydrates) and the isoenergetic standard diet (ST; 12.1% protein, 60% carbohydrates). During late pregnancy, maternal and umbilical glucose metabolism and fetal hepatic mRNA expression of gluconeogenic enzymes were examined. During an i.v. glucose tolerance test (IVGTT), the LP-HC-fed sows had lower insulin concentrations and area under the curve (AUC), and higher glucose:insulin ratios than the ST- and the HP-LC-fed sows (P < 0.05). Insulin sensitivity and glucose clearance were higher in the LP-HC sows compared with ST sows (P < 0.05). Glucagon concentrations during postabsorptive conditions and IVGTT, and glucose AUC during IVGTT, were higher in the HP-LC group compared with the other groups (P < 0.001). (13)C glucose oxidation was lower in the HP-LC sows than in the ST and LP-HC sows (P < 0.05). The HP-LC fetuses were lighter and had a higher brain:liver ratio than the ST group (P < 0.05). The umbilical arterial inositol concentration was greater in the HP-LC group (P < 0.05) and overall small fetuses (230-572 g) had higher values than medium and heavy fetuses (≥573 g) (P < 0.05). Placental lactate release was lower in the LP-HC group than in the ST group (P < 0.05). Fetal glucose extraction tended to be lower in the LP-HC group than in the ST group (P = 0.07). In the HP-LC and LP-HC fetuses, hepatic mRNA expression of cytosolic phosphoenolpyruvate carboxykinase (PCK1) and glucose-6-phosphatase (G6PC) was higher than in the ST fetuses (P < 0.05). In conclusion, the HP-LC and LP-HC sows adapted by reducing glucose turnover and oxidation and having higher glucose utilization, respectively. The HP-LC and LP

  1. Perinatal protein restriction affects milk free amino acid and fatty acid profile in lactating rats: potential role on pup growth and metabolic status.

    PubMed

    Martin Agnoux, Aurore; Antignac, Jean-Philippe; Boquien, Clair-Yves; David, Agnes; Desnots, Emmanuelle; Ferchaud-Roucher, Veronique; Darmaun, Dominique; Parnet, Patricia; Alexandre-Gouabau, Marie-Cécile

    2015-07-01

    Perinatal undernutrition affects not only fetal and neonatal growth but also adult health outcome, as suggested by the metabolic imprinting concept. Although maternal milk is the only channel through which nutrients are transferred from mother to offspring during the postnatal period, the impact of maternal undernutrition on milk composition is poorly understood. The present study investigates, in a rat model of nutritional programming, the effects of feeding an isocaloric, low-protein diet throughout gestation and lactation on milk composition and its possible consequences on offspring's growth and metabolic status. We used an integrated methodological approach that combined targeted analyses of macronutrients, free amino acid and fatty acid content throughout lactation, with an untargeted mass-spectrometric-based metabolomic phenotyping. Whereas perinatal dietary protein restriction failed to alter milk protein content, it dramatically decreased the concentration of most free amino acids at the end of lactation. Interestingly, a decrease of several amino acids involved in insulin secretion or gluconeogenesis was observed, suggesting that maternal protein restriction during the perinatal period may impact the insulinotrophic effect of milk, which may, in turn, account for the slower growth of the suckled male offspring. Besides, the decrease in sulfur amino acids may alter redox status in the offspring. Maternal undernutrition was also associated with an increase in milk total fatty acid content, with modifications in their pattern. Altogether, our results show that milk composition is clearly influenced by maternal diet and suggest that alterations in milk composition may play a role in offspring growth and metabolic programming. PMID:25935308

  2. Protein metabolism and requirements.

    PubMed

    Biolo, Gianni

    2013-01-01

    Skeletal muscle adaptation to critical illness includes insulin resistance, accelerated proteolysis, and increased release of glutamine and the other amino acids. Such amino acid efflux from skeletal muscle provides precursors for protein synthesis and energy fuel to the liver and to the rapidly dividing cells of the intestinal mucosa and the immune system. From these adaptation mechanisms, severe muscle wasting, glutamine depletion, and hyperglycemia, with increased patient morbidity and mortality, may ensue. Protein/amino acid nutrition, through either enteral or parenteral routes, plays a pivotal role in treatment of metabolic abnormalities in critical illness. In contrast to energy requirement, which can be accurately assessed by indirect calorimetry, methods to determine individual protein/amino acid needs are not currently available. In critical illness, a decreased ability of protein/amino acid intake to promote body protein synthesis is defined as anabolic resistance. This abnormality leads to increased protein/amino acid requirement and relative inefficiency of nutritional interventions. In addition to stress mediators, immobility and physical inactivity are key determinants of anabolic resistance. The development of mobility protocols in the intensive care unit should be encouraged to enhance the efficacy of nutrition. In critical illness, protein/amino acid requirement has been defined as the intake level associated with the lowest rate of catabolism. The optimal protein-sparing effects in patients receiving adequate energy are achieved when protein/amino acids are administered at rates between 1.3 and 1.5 g/kg/day. Extra glutamine supplementation is required in conditions of severe systemic inflammatory response. Protein requirement increases during hypocaloric feeding and in patients with acute renal failure on continuous renal replacement therapy. Evidence suggests that receiving adequate protein/amino acid intake may be more important than achieving

  3. The plastid outer envelope protein OEP16 affects metabolic fluxes during ABA-controlled seed development and germination

    PubMed Central

    Pudelski, Birgit; Schock, Annette; Hoth, Stefan; Radchuk, Ruslana; Weber, Hans; Hofmann, Jörg; Sonnewald, Uwe; Soll, Jürgen; Philippar, Katrin

    2012-01-01

    Previously, the OEP16.1 channel pore in the outer envelope membrane of mature pea (Pisum sativum) chloroplasts in vitro has been characterized to be selective for amino acids. Isolation of OEP16.2, a second OEP16 isoform from pea, in the current study allowed membrane localization and gene expression of OEP16 to be followed throughout seed development and germination of Arabidopsis thaliana and P. sativum. Thereby it can be shown on the transcript and protein level that the isoforms OEP16.1 and OEP16.2 in both plant species are alternating: whereas OEP16.1 is prominent in early embryo development and first leaves of the growing plantlet, OEP16.2 dominates in late seed development stages, which are associated with dormancy and desiccation, as well as early germination events. Further, OEP16.2 expression in seeds is under control of the phytohormone abscisic acid (ABA), leading to an ABA-hypersensitive phenotype of germinating oep16 knockout mutants. In consequence, the loss of OEP16 causes metabolic imbalance, in particular that of amino acids during seed development and early germination. It is thus concluded that in vivo OEP16 most probably functions in shuttling amino acids across the outer envelope of seed plastids. PMID:22155670

  4. Single nucleotide polymorphisms linked to mitochondrial uncoupling protein genes UCP2 and UCP3 affect mitochondrial metabolism and healthy aging in female nonagenarians.

    PubMed

    Kim, Sangkyu; Myers, Leann; Ravussin, Eric; Cherry, Katie E; Jazwinski, S Michal

    2016-08-01

    Energy expenditure decreases with age, but in the oldest-old, energy demand for maintenance of body functions increases with declining health. Uncoupling proteins have profound impact on mitochondrial metabolic processes; therefore, we focused attention on mitochondrial uncoupling protein genes. Alongside resting metabolic rate (RMR), two SNPs in the promoter region of UCP2 were associated with healthy aging. These SNPs mark potential binding sites for several transcription factors; thus, they may affect expression of the gene. A third SNP in the 3'-UTR of UCP3 interacted with RMR. This UCP3 SNP is known to impact UCP3 expression in tissue culture cells, and it has been associated with body weight and mitochondrial energy metabolism. The significant main effects of the UCP2 SNPs and the interaction effect of the UCP3 SNP were also observed after controlling for fat-free mass (FFM) and physical-activity related energy consumption. The association of UCP2/3 with healthy aging was not found in males. Thus, our study provides evidence that the genetic risk factors for healthy aging differ in males and females, as expected from the differences in the phenotypes associated with healthy aging between the two sexes. It also has implications for how mitochondrial function changes during aging. PMID:26965008

  5. Perturbations of Amino Acid Metabolism Associated with Glyphosate-Dependent Inhibition of Shikimic Acid Metabolism Affect Cellular Redox Homeostasis and Alter the Abundance of Proteins Involved in Photosynthesis and Photorespiration1[W][OA

    PubMed Central

    Vivancos, Pedro Diaz; Driscoll, Simon P.; Bulman, Christopher A.; Ying, Liu; Emami, Kaveh; Treumann, Achim; Mauve, Caroline; Noctor, Graham; Foyer, Christine H.

    2011-01-01

    The herbicide glyphosate inhibits the shikimate pathway of the synthesis of amino acids such as phenylalanine, tyrosine, and tryptophan. However, much uncertainty remains concerning precisely how glyphosate kills plants or affects cellular redox homeostasis and related processes in glyphosate-sensitive and glyphosate-resistant crop plants. To address this issue, we performed an integrated study of photosynthesis, leaf proteomes, amino acid profiles, and redox profiles in the glyphosate-sensitive soybean (Glycine max) genotype PAN809 and glyphosate-resistant Roundup Ready Soybean (RRS). RRS leaves accumulated much more glyphosate than the sensitive line but showed relatively few changes in amino acid metabolism. Photosynthesis was unaffected by glyphosate in RRS leaves, but decreased abundance of photosynthesis/photorespiratory pathway proteins was observed together with oxidation of major redox pools. While treatment of a sensitive genotype with glyphosate rapidly inhibited photosynthesis and triggered the appearance of a nitrogen-rich amino acid profile, there was no evidence of oxidation of the redox pools. There was, however, an increase in starvation-associated and defense proteins. We conclude that glyphosate-dependent inhibition of soybean leaf metabolism leads to the induction of defense proteins without sustained oxidation. Conversely, the accumulation of high levels of glyphosate in RRS enhances cellular oxidation, possibly through mechanisms involving stimulation of the photorespiratory pathway. PMID:21757634

  6. Dietary protein level and source differentially affect bone metabolism, strength, and intestinal calcium transporter expression during ad libitum and food-restricted conditions in male rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High protein diets may attenuate bone loss during energy restriction (ER). The objective of the current study was to determine whether high protein diets suppress bone turnover and improve bone quality in rats during ER and whether dietary protein source affects this relationship. Eighty 12-week o...

  7. [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. PMID:25550238

  8. Dietary sardine protein lowers insulin resistance, leptin and TNF-α and beneficially affects adipose tissue oxidative stress in rats with fructose-induced metabolic syndrome.

    PubMed

    Madani, Zohra; Louchami, Karim; Sener, Abdullah; Malaisse, Willy J; Ait Yahia, Dalila

    2012-02-01

    The present study aims at exploring the effects of sardine protein on insulin resistance, plasma lipid profile, as well as oxidative and inflammatory status in rats with fructose-induced metabolic syndrome. Rats were fed sardine protein (S) or casein (C) diets supplemented or not with high-fructose (HF) for 2 months. Rats fed the HF diets had greater body weight and adiposity and lower food intake as compared to control rats. Increased plasma glucose, insulin, HbA1C, triacylglycerols, free fatty acids and impaired glucose tolerance and insulin resistance was observed in HF-fed rats. Moreover, a decline in adipose tissues antioxidant status and a rise in lipid peroxidation and plasma TNF-α and fibrinogen were noted. Rats fed sardine protein diets exhibited lower food intake and fat mass than those fed casein diets. Sardine protein diets diminished plasma insulin and insulin resistance. Plasma triacylglycerol and free fatty acids were also lower, while those of α-tocopherol, taurine and calcium were enhanced as compared to casein diets. Moreover, S-HF diet significantly decreased plasma glucose and HbA1C. Sardine protein consumption lowered hydroperoxide levels in perirenal and brown adipose tissues. The S-HF diet, as compared to C-HF diet decreased epididymal hydroperoxides. Feeding sardine protein diets decreased brown adipose tissue carbonyls and increased glutathione peroxidase activity. Perirenal and epididymal superoxide dismutase and catalase activities and brown catalase activity were significantly greater in S-HF group than in C-HF group. Sardine protein diets also prevented hyperleptinemia and reduced inflammatory status in comparison with rats fed casein diets. Taken together, these results support the beneficial effect of sardine protein in fructose-induced metabolic syndrome on such variables as hyperglycemia, insulin resistance, hyperlipidemia and oxidative and inflammatory status, suggesting the possible use of sardine protein as a protective

  9. Homocysteine thiolactone affects protein ubiquitination in yeast.

    PubMed

    Bretes, Ewa; Zimny, Jarosław

    2013-01-01

    The formation of homocysteine thiolactone (HcyTl) from homocysteine occurs in all examined so far organisms including bacteria, yeast, and humans. Protein N-homocysteinylation at the ε-amino group of lysine is an adverse result of HcyTl accumulation. Since tagging of proteins by ubiquitination before their proteasomal degradation takes place at the same residue, we wondered how N-homocysteinylation may affect the ubiquitination of proteins. We used different yeast strains carrying mutations in genes involved in the homocysteine metabolism. We found positive correlation between the concentration of endogenous HcyTl and the concentration of ubiquitinated proteins. This suggests that N-homocysteinylation of proteins apparently does not preclude but rather promotes their decomposition. PMID:24051443

  10. Affective Disorders, Bone Metabolism, and Osteoporosis.

    PubMed

    Mezuk, Briana

    2008-12-01

    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.

  11. 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

  12. High or low dietary carbohydrate:protein ratios during first-feeding affect glucose metabolism and intestinal microbiota in juvenile rainbow trout.

    PubMed

    Geurden, I; Mennigen, J; Plagnes-Juan, E; Veron, V; Cerezo, T; Mazurais, D; Zambonino-Infante, J; Gatesoupe, J; Skiba-Cassy, S; Panserat, S

    2014-10-01

    Based on the concept of nutritional programming in mammals, we tested whether an acute hyperglucidic-hypoproteic stimulus during first feeding could induce long-term changes in nutrient metabolism in rainbow trout. Trout alevins received during the five first days of exogenous feeding either a hyperglucidic (40% gelatinized starch + 20% glucose) and hypoproteic (20%) diet (VLP diet) or a high-protein (60%) glucose-free diet (HP diet, control). Following a common 105-day period on a commercial diet, both groups were then challenged (65 days) with a carbohydrate-rich diet (28%). Short- and long-term effects of the early stimuli were evaluated in terms of metabolic marker gene expressions and intestinal microbiota as initial gut colonisation is essential for regulating the development of the digestive system. In whole alevins (short term), diet VLP relative to HP rapidly increased gene expressions of glycolytic enzymes, while those involved in gluconeogenesis and amino acid catabolism decreased. However, none of these genes showed persistent molecular adaptation in the liver of challenged juveniles (long term). By contrast, muscle of challenged juveniles subjected previously to the VLP stimulus displayed downregulated expression of markers of glycolysis and glucose transport (not seen in the short term). These fish also had higher plasma glucose (9 h postprandial), suggesting impaired glucose homeostasis induced by the early stimulus. The early stimulus did not modify the expression of the analysed metabolism-related microRNAs, but had short- and long-term effects on intestinal fungi (not bacteria) profiles. In summary, our data show that a short hyperglucidic-hypoproteic stimulus during early life may have a long-term influence on muscle glucose metabolism and intestinal microbiota in trout.

  13. High or low dietary carbohydrate:protein ratios during first-feeding affect glucose metabolism and intestinal microbiota in juvenile rainbow trout.

    PubMed

    Geurden, I; Mennigen, J; Plagnes-Juan, E; Veron, V; Cerezo, T; Mazurais, D; Zambonino-Infante, J; Gatesoupe, J; Skiba-Cassy, S; Panserat, S

    2014-10-01

    Based on the concept of nutritional programming in mammals, we tested whether an acute hyperglucidic-hypoproteic stimulus during first feeding could induce long-term changes in nutrient metabolism in rainbow trout. Trout alevins received during the five first days of exogenous feeding either a hyperglucidic (40% gelatinized starch + 20% glucose) and hypoproteic (20%) diet (VLP diet) or a high-protein (60%) glucose-free diet (HP diet, control). Following a common 105-day period on a commercial diet, both groups were then challenged (65 days) with a carbohydrate-rich diet (28%). Short- and long-term effects of the early stimuli were evaluated in terms of metabolic marker gene expressions and intestinal microbiota as initial gut colonisation is essential for regulating the development of the digestive system. In whole alevins (short term), diet VLP relative to HP rapidly increased gene expressions of glycolytic enzymes, while those involved in gluconeogenesis and amino acid catabolism decreased. However, none of these genes showed persistent molecular adaptation in the liver of challenged juveniles (long term). By contrast, muscle of challenged juveniles subjected previously to the VLP stimulus displayed downregulated expression of markers of glycolysis and glucose transport (not seen in the short term). These fish also had higher plasma glucose (9 h postprandial), suggesting impaired glucose homeostasis induced by the early stimulus. The early stimulus did not modify the expression of the analysed metabolism-related microRNAs, but had short- and long-term effects on intestinal fungi (not bacteria) profiles. In summary, our data show that a short hyperglucidic-hypoproteic stimulus during early life may have a long-term influence on muscle glucose metabolism and intestinal microbiota in trout. PMID:25274323

  14. Trichoderma secondary metabolites that affect plant metabolism.

    PubMed

    Vinale, Francesco; Sivasithamparam, Krishnapillai; Ghisalberti, Emilio L; Ruocco, Michelina; Wood, Sheridan; Lorito, Matteo

    2012-11-01

    Recently, there have been many exciting new developments relating to the use of Trichoderma spp. as agents for biocontrol of pathogens and as plant growth promoters. Several mechanisms have been proposed to explain the positive effects of these microorganisms on the plant host. One factor that contributes to their beneficial biological activities is related to the wide variety of metabolites that they produce. These metabolites have been found not only to directly inhibit the growth and pathogenic activities of the parasites, but also to increase disease resistance by triggering the system of defence in the plant host. In addition, these metabolites are also capable of enhancing plant growth, which enables the plant to counteract the disease with compensatory vegetative growth by the augmented production of root and shoot systems. This review takes into account the Trichoderma secondary metabolites that affect plant metabolism and that may play an important role in the complex interactions of this biocontrol agent with the plant and pathogens.

  15. Leucine and protein metabolism in obese zucker rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Branched-chain amino acids (BCAAs) are circulating nutrient signals for protein accretion, however they increase in obesity and appear to prognosticate diabetes onset. To understand the mechanisms whereby obesity affects BCAAs and protein metabolism, we employed metabolomics and measured rates of [1...

  16. High dietary fat-induced obesity in Wistar rats and type 2 diabetes in nonobese Goto-Kakizaki rats differentially affect retinol binding protein 4 expression and vitamin A metabolism.

    PubMed

    Shirai, Tomomi; Shichi, Yuta; Sato, Miyuki; Tanioka, Yuri; Furusho, Tadasu; Ota, Toru; Tadokoro, Tadahiro; Suzuki, Tsukasa; Kobayashi, Ken-Ichi; Yamamoto, Yuji

    2016-03-01

    Obesity is a major risk factor for type 2 diabetes, which is caused mainly by insulin resistance. Retinol binding protein 4 (RBP4) is the only specific transport protein for retinol in the serum. RBP4 level is increased in the diabetic state and high-fat condition, indicating that retinol metabolism may be affected under these conditions. However, the precise effect of diabetes and high fat-induced obesity on retinol metabolism is unknown. In this study, we examined differences in retinol metabolite levels in rat models of diet-induced obesity and type 2 diabetes (Goto-Kakizaki [GK] rat). Four-week-old male Wistar and GK rats were given either a control diet (AIN-93G) or a high-fat diet (HFD, 40% fat kJ). After 15 weeks of feeding, the RBP4 levels increased by 2-fold in the serum of GK rats but not HFD-fed rats. The hepatic retinol concentration of HFD-fed rats was approximately 50% that of the controls (P < .01). In contrast, the renal retinol concentrations of GK rats increased by 70% (P < .01). However, expression of RARβ in the kidney, which was induced in a retinoic acid-dependent manner, was downregulated by 90% (P < .01) in GK rats. In conclusion, diabetes and obesity affected retinol metabolism differently, and the effects were different in different peripheral tissues. The impact of HFD may be limited to the storage of hepatic vitamin A as retinyl palmitate. In particular, our data indicate that renal retinoic acid production might represent an important target for the treatment of type 2 diabetes mellitus. PMID:26923513

  17. Blockage of the Neonatal Leptin Surge Affects the Gene Expression of Growth Factors, Glial Proteins, and Neuropeptides Involved in the Control of Metabolism and Reproduction in Peripubertal Male and Female Rats.

    PubMed

    Mela, Virginia; Díaz, Francisca; Lopez-Rodriguez, Ana Belen; Vázquez, María Jesús; Gertler, Arieh; Argente, Jesús; Tena-Sempere, Manuel; Viveros, María-Paz; Chowen, Julie A

    2015-07-01

    Leptin (Lep) is important in the development of neuroendocrine circuits involved in metabolic control. Because both Lep and metabolism influence pubertal development, we hypothesized that early changes in Lep signaling could also modulate hypothalamic (HT) systems involved in reproduction. We previously demonstrated that a single injection of a Lep antagonist (Antag) on postnatal day (PND)9, coincident with the neonatal Lep peak, induced sexually dimorphic modifications in trophic factors and markers of cell turnover and neuronal maturation in the HT on PND13. Here, our aim was to investigate whether the alterations induced by Lep antagonism persist into puberty. Accordingly, male and female rats were treated with a pegylated super Lep Antag from PND5 to PND9 and killed just before the normal appearance of external signs of puberty (PND33 in females and PND43 in males). There was no effect on body weight, but in males food intake increased, subcutaneous adipose tissue decreased and HT neuropeptide Y and Agouti-related peptide mRNA levels were reduced, with no effect in females. In both sexes, the Antag increased HT mRNA levels of the kisspeptin receptor, G protein-coupled recepter 54 (Gpr54). Expression of the Lep receptor, trophic factors, and glial markers were differently affected in the HT of peripubertal males and females. Lep production in adipose tissue was decreased in Antag-treated rats of both sexes, with production of other cytokines being differentially regulated between sexes. In conclusion, in addition to the long-term effects on metabolism, changes in neonatal Lep levels modifies factors involved in reproduction that could possibly affect sexual maturation.

  18. Testosterone increases the muscle protein synthesis rate but does not affect very-low-density lipoprotein metabolism in obese premenopausal women

    PubMed Central

    Wang, Xuewen; Smith, Gordon I.; Patterson, Bruce W.; Reeds, Dominic N.; Kampelman, Janine; Magkos, Faidon

    2012-01-01

    Men and women with hyperandrogenemia have a more proatherogenic plasma lipid profile [e.g., greater triglyceride (TG) and total and low-density lipoprotein-cholesterol and lower high-density lipoprotein-cholesterol concentrations] than healthy premenopausal women. Furthermore, castration of male rats markedly reduces testosterone availability below normal and decreases plasma TG concentration, and testosterone replacement reverses this effect. Testosterone is, therefore, thought to be an important regulator of plasma lipid homeostasis. However, little is known about the effect of testosterone on plasma TG concentration and kinetics. Furthermore, testosterone is a potent skeletal muscle protein anabolic agent in men, but its effect on muscle protein turnover in women is unknown. We measured plasma lipid concentrations, hepatic very low density lipoprotein (VLDL)-TG and VLDL-apolipoprotein B-100 secretion rates, and the muscle protein fractional synthesis rate in 10 obese women before and after trandermal testosterone (1.25 g of 1% AndroGel daily) treatment for 3 wk. Serum total and free testosterone concentrations increased (P < 0.05) by approximately sevenfold in response to testosterone treatment, reaching concentrations that are comparable to those in women with hyperandrogenemia, but lower than the normal range for eugonadal men. Except for a small (∼10%) decrease in plasma high-density lipoprotein particle and cholesterol concentrations (P < 0.04), testosterone therapy had no effect on plasma lipid concentrations, lipoprotein particle sizes, and hepatic VLDL-TG and VLDL-apolipoprotein B-100 secretion rates (all P > 0.05); the muscle protein fractional synthesis rate, however, increased by ∼45% (P < 0.001). We conclude that testosterone is a potent skeletal muscle protein anabolic agent, but not an important regulator of plasma lipid homeostasis in obese women. PMID:22252942

  19. Posttranslational Protein Modifications in Plant Metabolism1

    PubMed Central

    Friso, Giulia; van Wijk, Klaas J.

    2015-01-01

    Posttranslational modifications (PTMs) of proteins greatly expand proteome diversity, increase functionality, and allow for rapid responses, all at relatively low costs for the cell. PTMs play key roles in plants through their impact on signaling, gene expression, protein stability and interactions, and enzyme kinetics. Following a brief discussion of the experimental and bioinformatics challenges of PTM identification, localization, and quantification (occupancy), a concise overview is provided of the major PTMs and their (potential) functional consequences in plants, with emphasis on plant metabolism. Classic examples that illustrate the regulation of plant metabolic enzymes and pathways by PTMs and their cross talk are summarized. Recent large-scale proteomics studies mapped many PTMs to a wide range of metabolic functions. Unraveling of the PTM code, i.e. a predictive understanding of the (combinatorial) consequences of PTMs, is needed to convert this growing wealth of data into an understanding of plant metabolic regulation. PMID:26338952

  20. Higher Total Protein Intake and Change in Total Protein Intake Affect Body Composition but Not Metabolic Syndrome Indexes in Middle-Aged Overweight and Obese Adults Who Perform Resistance and Aerobic Exercise for 36 Weeks123

    PubMed Central

    Campbell, Wayne W; Kim, Jung Eun; Amankwaah, Akua F; Gordon, Susannah L; Weinheimer-Haus, Eileen M

    2015-01-01

    Background: Studies assessing the effects of protein supplementation on changes in body composition (BC) and health rarely consider the impact of total protein intake (TPro) or the change in TPro (CTPro) from participants’ usual diets. Objective: This secondary data analysis assessed the impact of TPro and CTPro on changes in BC and metabolic syndrome (MetS) indexes in overweight and obese middle-aged adults who participated in an exercise training program. Methods: Men and women [n = 117; age: 50 ± 0.7 y, body mass index (BMI; in kg/m2): 30.1 ± 0.3; means ± SEs] performed resistance exercise 2 d/wk and aerobic exercise 1 d/wk and consumed an unrestricted diet along with 200-kcal supplements (0, 10, 20, or 30 g whey protein) twice daily for 36 wk. Protein intake was assessed via 4-d food records. Multiple linear regression model and stratified analysis were applied for data analyses. Results: Among all subjects, TPro and CTPro were inversely associated (P < 0.05) with changes in body mass, fat mass (FM), and BMI. Changes in BC were different (P < 0.05) among groups that consumed <1.0 (n = 43) vs. ≥1.0 to <1.2 (n = 29) vs. ≥1.2 g · kg−1 · d−1 (n = 45). The TPro group with ≥1.0 to <1.2 g · kg−1 · d−1 reduced FM and %FM and increased percentage of LM (%LM) compared with the lowest TPro group, whereas the TPro group with ≥1.2 g · kg−1 · d−1 presented intermediate responses on changes in FM, %FM, and %LM. The gain in LM was not different among groups. In addition, MetS indexes were not influenced by TPro and CTPro. Conclusions: In conjunction with exercise training, higher TPro promoted positive changes in BC but not in MetS indexes in overweight and obese middle-aged adults. Changes in TPro from before to during the intervention also influenced BC responses and should be considered in future research when different TPro is achieved via diet or supplements. This trial was registered at clinicaltrials.gov as NCT00812409. PMID:26246322

  1. [Pathogenetic correction of metabolic disturbances in chronic liver affections].

    PubMed

    Romantsov, M G; Petrov, A Iu; Aleksandrova, L N; Sukhanov, D S; Kovalenko, A L

    2012-01-01

    The available drugs for the treatment of chronic liver affections (the adequate model is chronic hepatitis C) include agents of metabolic therapy, whose efficacy is not always enough, that required the search for original mitochondrial substrates on the basis of succinate. Such agents were composed as a pharmaceutical group named "Substrates of Energetic Metabolism" or "Substrate Antihypoxants". The review presents the description of the pharmacological effects of remaxole and cytoflavin, evident from lower levels of active metabolites of oxygen that increases the clinical efficacy of the therapy. Their role in the metabolic reactions in chronic liver affections is exclusive and rather actual. PMID:23700935

  2. Inherited metabolic diseases affecting the carrier.

    PubMed

    Endres, W

    1997-03-01

    The objective of this review is to draw attention to those inherited metabolic traits which are potentially harmful also for the carrier, and to outline preventive measures, at least for obligate heterozygotes, i.e. parents of homozygous children. Concerning carriers of food-dependent abnormalities, early vascular disease in homocystinuria, hyperammonaemic episodes in ornithine transcarbamylase deficiency, presenile cataracts in galactosaemia as well as galactokinase deficiency, spastic paraparesis in X-linked adrenoleukodystrophy, and HELLP syndrome in mothers of babies with long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency have to be mentioned. In the group of food-independent disorders, clinical features in carriers may be paraesthesias and corneal dystrophy in Fabry disease, lens clouding in Lowe syndrome, lung and/or liver diseases in alpha 1-antitrypsin deficiency, and renal stones in cystinuria type II and III. Finally, two monogenic carrier states are known which in pregnant individuals could possibly afflict the developing fetus, i.e. heterozygosity for galactosaemia and for phenylketonuria. Elevated levels of galactose-1-phosphate have been found in red blood cells of infants heterozygous for galactosaemia born to heterozygous mothers. Aspartame in very high doses is reported to increase blood phenylalanine levels in heterozygotes for phenylketonuria, thus being a risk for the fetus of a heterozygous mother. For some of these carrier states preventive measures can be recommended, e.g. restriction of lactose in parents and heterozygous grandparents of children with galactosaemia and galactokinase deficiency as well as transiently in infants heterozygous for galactosaemia, dietary supplementation with monounsaturated fatty acids in symptomatic carriers for X-linked adrenoleukodystrophy, avoidance of smoking and alcohol in heterozygotes for alpha 1-antitrypsin deficiency, avoidance of episodes of dehydration in heterozygotes for cystinuria, and

  3. Effects of metabolic rate on protein evolution.

    PubMed

    Gillooly, James F; McCoy, Michael W; Allen, Andrew P

    2007-12-22

    Since the modern evolutionary synthesis was first proposed early in the twentieth century, attention has focused on assessing the relative contribution of mutation versus natural selection on protein evolution. Here we test a model that yields general quantitative predictions on rates of protein evolution by combining principles of individual energetics with Kimura's neutral theory. The model successfully predicts much of the heterogeneity in rates of protein evolution for diverse eukaryotes (i.e. fishes, amphibians, reptiles, birds, mammals) from different thermal environments. Data also show that the ratio of non-synonymous to synonymous nucleotide substitution is independent of body size, and thus presumably of effective population size. These findings indicate that rates of protein evolution are largely controlled by mutation rates, which in turn are strongly influenced by individual metabolic rate.

  4. How membrane surface affects protein structure.

    PubMed

    Bychkova, V E; Basova, L V; Balobanov, V A

    2014-12-01

    The immediate environment of the negatively charged membrane surface is characterized by decreased dielectric constant and pH value. These conditions can be modeled by water-alcohol mixtures at moderately low pH. Several globular proteins were investigated under these conditions, and their conformational behavior in the presence of phospholipid membranes was determined, as well as under conditions modeling the immediate environment of the membrane surface. These proteins underwent conformational transitions from the native to a molten globule-like state. Increased flexibility of the protein structure facilitated protein functioning. Our experimental data allow understanding forces that affect the structure of a protein functioning near the membrane surface (in other words, in the membrane field). Similar conformational states are widely reported in the literature. This indicates that the negatively charged membrane surface can serve as a moderately denaturing agent in the cell. We conclude that the effect of the membrane field on the protein structure must be taken into account.

  5. Environmental factors affecting pregnancy: endocrine disrupters, nutrients and metabolic pathways.

    PubMed

    Bazer, Fuller W; Wu, Guoyao; Johnson, Gregory A; Wang, Xiaoqiu

    2014-12-01

    Uterine adenogenesis, a unique post-natal event in mammals, is vulnerable to endocrine disruption by estrogens and progestins resulting in infertility or reduced prolificacy. The absence of uterine glands results in insufficient transport of nutrients into the uterine lumen to support conceptus development. Arginine, a component of histotroph, is substrate for production of nitric oxide, polyamines and agmatine and, with secreted phosphoprotein 1, it affects cytoskeletal organization of trophectoderm. Arginine is critical for development of the conceptus, pregnancy recognition signaling, implantation and placentation. Conceptuses of ungulates and cetaceans convert glucose to fructose which is metabolized via multiple pathways to support growth and development. However, high fructose corn syrup in soft drinks and foods may increase risks for metabolic disorders and increase insulin resistance in adults. Understanding endocrine disrupters and dietary substances, and novel pathways for nutrient metabolism during pregnancy can improve survival and growth, and prevent chronic metabolic diseases in offspring. PMID:25224489

  6. Can Supersaturation Affect Protein Crystal Quality?

    NASA Technical Reports Server (NTRS)

    Gorti, Sridhar

    2013-01-01

    In quiescent environments (microgravity, capillary tubes, gels) formation of a depletion zone is to be expected, due either to limited sedimentation, density driven convection or a combination of both. The formation of a depletion zone can: Modify solution supersaturation near crystal; Give rise to impurity partitioning. It is conjectured that both supersaturation and impurity partitioning affect protein crystal quality and size. Further detailed investigations on various proteins are needed to assess above hypothesis.

  7. How does cancer cell metabolism affect tumor migration and invasion?

    PubMed

    Han, Tianyu; Kang, De; Ji, Daokun; Wang, Xiaoyu; Zhan, Weihua; Fu, Minggui; Xin, Hong-Bo; Wang, Jian-Bin

    2013-01-01

    Cancer metastasis is the major cause of cancer-associated death. Accordingly, identification of the regulatory mechanisms that control whether or not tumor cells become "directed walkers" is a crucial issue of cancer research. The deregulation of cell migration during cancer progression determines the capacity of tumor cells to escape from the primary tumors and invade adjacent tissues to finally form metastases. The ability to switch from a predominantly oxidative metabolism to glycolysis and the production of lactate even when oxygen is plentiful is a key characteristic of cancer cells. This metabolic switch, known as the Warburg effect, was first described in 1920s, and affected not only tumor cell growth but also tumor cell migration. In this review, we will focus on the recent studies on how cancer cell metabolism affects tumor cell migration and invasion. Understanding the new aspects on molecular mechanisms and signaling pathways controlling tumor cell migration is critical for development of therapeutic strategies for cancer patients.

  8. Mitochondrial uncoupling proteins and energy metabolism

    PubMed Central

    Busiello, Rosa A.; Savarese, Sabrina; Lombardi, Assunta

    2015-01-01

    Understanding the metabolic factors that contribute to energy metabolism (EM) is critical for the development of new treatments for obesity and related diseases. Mitochondrial oxidative phosphorylation is not perfectly coupled to ATP synthesis, and the process of proton-leak plays a crucial role. Proton-leak accounts for a significant part of the resting metabolic rate (RMR) and therefore enhancement of this process represents a potential target for obesity treatment. Since their discovery, uncoupling proteins have stimulated great interest due to their involvement in mitochondrial-inducible proton-leak. Despite the widely accepted uncoupling/thermogenic effect of uncoupling protein one (UCP1), which was the first in this family to be discovered, the reactions catalyzed by its homolog UCP3 and the physiological role remain under debate. This review provides an overview of the role played by UCP1 and UCP3 in mitochondrial uncoupling/functionality as well as EM and suggests that they are a potential therapeutic target for treating obesity and its related diseases such as type II diabetes mellitus. PMID:25713540

  9. Protein acetylation in metabolism - metabolites and cofactors.

    PubMed

    Menzies, Keir J; Zhang, Hongbo; Katsyuba, Elena; Auwerx, Johan

    2016-01-01

    Reversible acetylation was initially described as an epigenetic mechanism regulating DNA accessibility. Since then, this process has emerged as a controller of histone and nonhistone acetylation that integrates key physiological processes such as metabolism, circadian rhythm and cell cycle, along with gene regulation in various organisms. The widespread and reversible nature of acetylation also revitalized interest in the mechanisms that regulate lysine acetyltransferases (KATs) and deacetylases (KDACs) in health and disease. Changes in protein or histone acetylation are especially relevant for many common diseases including obesity, diabetes mellitus, neurodegenerative diseases and cancer, as well as for some rare diseases such as mitochondrial diseases and lipodystrophies. In this Review, we examine the role of reversible acetylation in metabolic control and how changes in levels of metabolites or cofactors, including nicotinamide adenine dinucleotide, nicotinamide, coenzyme A, acetyl coenzyme A, zinc and butyrate and/or β-hydroxybutyrate, directly alter KAT or KDAC activity to link energy status to adaptive cellular and organismal homeostasis.

  10. Effect of acute heat stress on plant nutrient metabolism proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Abrupt heating decreased the levels (per unit total root protein) of all but one of the nutrient metabolism proteins examined, and for most of the proteins, effects were greater for severe vs. moderate heat stress. For many of the nutrient metabolism proteins, initial effects of heat (1 d) were r...

  11. 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. PMID:17438019

  12. Prediction of disease-related mutations affecting protein localization

    PubMed Central

    Laurila, Kirsti; Vihinen, Mauno

    2009-01-01

    Background Eukaryotic cells contain numerous compartments, which have different protein constituents. Proteins are typically directed to compartments by short peptide sequences that act as targeting signals. Translocation to the proper compartment allows a protein to form the necessary interactions with its partners and take part in biological networks such as signalling and metabolic pathways. If a protein is not transported to the correct intracellular compartment either the reaction performed or information carried by the protein does not reach the proper site, causing either inactivation of central reactions or misregulation of signalling cascades, or the mislocalized active protein has harmful effects by acting in the wrong place. Results Numerous methods have been developed to predict protein subcellular localization with quite high accuracy. We applied bioinformatics methods to investigate the effects of known disease-related mutations on protein targeting and localization by analyzing over 22,000 missense mutations in more than 1,500 proteins with two complementary prediction approaches. Several hundred putative localization affecting mutations were identified and investigated statistically. Conclusion Although alterations to localization signals are rare, these effects should be taken into account when analyzing the consequences of disease-related mutations. PMID:19309509

  13. Alterations in protein metabolism during space flight and inactivity

    NASA Technical Reports Server (NTRS)

    Ferrando, Arny A.; Paddon-Jones, Doug; Wolfe, Robert R.

    2002-01-01

    Space flight and the accompanying diminished muscular activity lead to a loss of body nitrogen and muscle function. These losses may affect crew capabilities and health in long-duration missions. Space flight alters protein metabolism such that the body is unable to maintain protein synthetic rates. A concomitant hypocaloric intake and altered anabolic/catabolic hormonal profiles may contribute to or exacerbate this problem. The inactivity associated with bedrest also reduces muscle and whole-body protein synthesis. For this reason, bedrest provides a good model for the investigation of potential exercise and nutritional countermeasures to restore muscle protein synthesis. We have demonstrated that minimal resistance exercise preserves muscle protein synthesis throughout bedrest. In addition, ongoing work indicates that an essential amino acid and carbohydrate supplement may ameliorate the loss of lean body mass and muscle strength associated with 28 d of bedrest. The investigation of inactivity-induced alterations in protein metabolism, during space flight or prolonged bedrest, is applicable to clinical populations and, in a more general sense, to the problems associated with the decreased activity that occur with aging.

  14. Can Solution Supersaturation Affect Protein Crystal Quality?

    NASA Technical Reports Server (NTRS)

    Gorti, Sridhar

    2013-01-01

    The formation of large protein crystals of "high quality" is considered a characteristic manifestation of microgravity. The physical processes that predict the formation of large, high quality protein crystals in the microgravity environment of space are considered rooted in the existence of a "depletion zone" in the vicinity of crystal. Namely, it is considered reasonable that crystal quality suffers in earth-grown crystals as a result of the incorporation of large aggregates, micro-crystals and/or large molecular weight "impurities", processes which are aided by density driven convective flow or mixing at the crystal-liquid interface. Sedimentation and density driven convection produce unfavorable solution conditions in the vicinity of the crystal surface, which promotes rapid crystal growth to the detriment of crystal size and quality. In this effort, we shall further present the hypothesis that the solution supersaturatoin at the crystal surface determines the growth mechanism, or mode, by which protein crystals grow. It is further hypothesized that protein crystal quality is affected by the mechanism or mode of crystal growth. Hence the formation of a depletion zone in microgravity environment is beneficial due to inhibition of impurity incorporatoin as well as preventing a kinetic roughening transition. It should be noted that for many proteins the magnitude of neither protein crystal growth rates nor solution supersaturation are predictors of a kinetic roughening transition. That is, the kinetic roughening transition supersaturation must be dtermined for each individual protein.

  15. Perilipin-related protein regulates lipid metabolism in C. elegans

    PubMed Central

    Chughtai, Ahmed Ali; Kaššák, Filip; Kostrouchová, Markéta; Novotný, Jan Philipp; Krause, Michael W.; Kostrouch, Zdenek

    2015-01-01

    Perilipins are lipid droplet surface proteins that contribute to fat metabolism by controlling the access of lipids to lipolytic enzymes. Perilipins have been identified in organisms as diverse as metazoa, fungi, and amoebas but strikingly not in nematodes. Here we identify the protein encoded by the W01A8.1 gene in Caenorhabditis elegans as the closest homologue and likely orthologue of metazoan perilipin. We demonstrate that nematode W01A8.1 is a cytoplasmic protein residing on lipid droplets similarly as human perilipins 1 and 2. Downregulation or elimination of W01A8.1 affects the appearance of lipid droplets resulting in the formation of large lipid droplets localized around the dividing nucleus during the early zygotic divisions. Visualization of lipid containing structures by CARS microscopy in vivo showed that lipid-containing structures become gradually enlarged during oogenesis and relocate during the first zygotic division around the dividing nucleus. In mutant embryos, the lipid containing structures show defective intracellular distribution in subsequent embryonic divisions and become gradually smaller during further development. In contrast to embryos, lipid-containing structures in enterocytes and in epidermal cells of adult animals are smaller in mutants than in wild type animals. Our results demonstrate the existence of a perilipin-related regulation of fat metabolism in nematodes and provide new possibilities for functional studies of lipid metabolism. PMID:26357594

  16. Ethanol impairs post-prandial hepatic protein metabolism.

    PubMed Central

    De Feo, P; Volpi, E; Lucidi, P; Cruciani, G; Monacchia, F; Reboldi, G; Santeusanio, F; Bolli, G B; Brunetti, P

    1995-01-01

    The effects of acute ethanol ingestion on whole body and hepatic protein metabolism in humans are not known. To simulate social drinking, we compared the effects of the association of a mixed meal (632 kcal, 17% amino acids, 50% glucose, 33% lipids) with a bottle of either table wine (ethanol content 71 g) or water on the estimates ([1-14C]-leucine infusion) of whole body protein breakdown, oxidation, and synthesis, and on the intravascular fractional secretory rates (FSR) of hepatically (albumin, fibrinogen) and extrahepatically (IgG) synthesized plasma proteins in two randomized groups (ethanol n = 7, water n = 7) of healthy nonalcoholic volunteers. Each study was carried out for 8 h. Protein kinetics were measured in the overnight post-absorptive state, over the first 4 h, and during a meal infusion (via a nasogastric feeding tube at constant rate) combined with the oral ingestion of wine or water, over the last 4 h. When compared with water, wine ingestion during the meal reduced (P < 0.03) by 24% the rate of leucine oxidation, did not modify the estimates of whole body protein breakdown and synthesis, reduced (P < 0.01) by approximately 30% the FSR of albumin and fibrinogen, but did not affect IgG FSR. In conclusion, 70 g of ethanol, an amount usual among social drinkers, impairs hepatic protein metabolism. The habitual consumption of such amounts by reducing the synthesis and/or secretion of hepatic proteins might lead to the progressive development of liver injury and to hypoalbuminemia also in the absence of protein malnutrition. PMID:7706451

  17. Early postnatal feed restriction reduces liver connective tissue levels and affects H3K9 acetylation state of regulated genes associated with protein metabolism in low birth weight pigs.

    PubMed

    Nebendahl, Constance; Görs, Solvig; Albrecht, Elke; Krüger, Ricarda; Martens, Karen; Giller, Katrin; Hammon, Harald M; Rimbach, Gerald; Metges, Cornelia C

    2016-03-01

    Intrauterine growth retardation is associated with metabolic consequences in adulthood. Since our previous data indicate birth weight-dependent effects of feed restriction (R) on protein degradation processes in the liver, it should be investigated whether effects on connective tissue turnover are obvious and could be explained by global changes of histone H3K9me3 and H3K9ac states in regulated genes. For this purpose, female littermate pigs with low (U) or normal (N) birth weight were subjected to 3-week R (60% of ad libitum fed controls) with subsequent refeeding (REF) for further 5 weeks. The 3-week R-period induced a significant reduction of connective tissue area by 43% in the liver of U animals at 98 d of age, which was not found in age-matched N animals. Of note, after REF at 131 d of age, in previously feed-restricted U animals (UR), the percentage of mean connective tissue was only 53% of ad libitum fed controls (UK), indicating a persistent effect. In U animals, R induced H3K9 acetylation of regulated genes (e.g. XBP1, ERLEC1, GALNT2, PTRH2), which were inter alia associated with protein metabolism. In contrast, REF was mostly accompanied by deacetylation in U and N animals. Thus, our epigenetic data may give a first explanation for the observed birth weight-dependent differences in this connective tissue phenotype.

  18. How Hofmeister ion interactions affect protein stability.

    PubMed Central

    Baldwin, R L

    1996-01-01

    Model compound studies in the literature show how Hofmeister ion interactions affect protein stability. Although model compound results are typically obtained as salting-out constants, they can be used to find out how the interactions affect protein stability. The null point in the Hofmeister series, which divides protein denaturants from stabilizers, arises from opposite interactions with different classes of groups: Hofmeister ions salt out nonpolar groups and salt in the peptide group. Theories of how Hofmeister ion interactions work need to begin by explaining the mechanisms of these two classes of interactions. Salting-out nonpolar groups has been explained by the cavity model, but its use is controversial. When applied to model compound data, the cavity model 1) uses surface tension increments to predict the observed values of the salting-out constants, within a factor of 3, and 2) predicts that the salting-out constant should increase with the number of carbon atoms in the aliphatic side chain of an amino acid, as observed. The mechanism of interaction between Hofmeister ions and the peptide group is not well understood, and it is controversial whether this interaction is ion-specific, or whether it is nonspecific and the apparent specificity resides in interactions with nearby nonpolar groups. A nonspecific salting-in interaction is known to occur between simple ions and dipolar molecules; it depends on ionic strength, not on position in the Hofmeister series. A theory by Kirkwood predicts the strength of this interaction and indicates that it depends on the first power of the ionic strength. Ions interact with proteins in various ways besides the Hofmeister ion interactions discussed here, especially by charge interactions. Much of what is known about these interactions comes from studies by Serge Timasheff and his co-workers. A general model, suitable for analyzing diverse ion-protein interactions, is provided by the two-domain model of Record and co

  19. Protein acetylation in metabolism - metabolites and cofactors.

    PubMed

    Menzies, Keir J; Zhang, Hongbo; Katsyuba, Elena; Auwerx, Johan

    2016-01-01

    Reversible acetylation was initially described as an epigenetic mechanism regulating DNA accessibility. Since then, this process has emerged as a controller of histone and nonhistone acetylation that integrates key physiological processes such as metabolism, circadian rhythm and cell cycle, along with gene regulation in various organisms. The widespread and reversible nature of acetylation also revitalized interest in the mechanisms that regulate lysine acetyltransferases (KATs) and deacetylases (KDACs) in health and disease. Changes in protein or histone acetylation are especially relevant for many common diseases including obesity, diabetes mellitus, neurodegenerative diseases and cancer, as well as for some rare diseases such as mitochondrial diseases and lipodystrophies. In this Review, we examine the role of reversible acetylation in metabolic control and how changes in levels of metabolites or cofactors, including nicotinamide adenine dinucleotide, nicotinamide, coenzyme A, acetyl coenzyme A, zinc and butyrate and/or β-hydroxybutyrate, directly alter KAT or KDAC activity to link energy status to adaptive cellular and organismal homeostasis. PMID:26503676

  20. 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

  1. Metabolic effects of milk protein intake strongly depend on pre-existing metabolic and exercise status.

    PubMed

    Melnik, Bodo C; Schmitz, Gerd; John, Swen; Carrera-Bastos, Pedro; Lindeberg, Staffan; Cordain, Loren

    2013-01-01

    Milk protein intake has recently been suggested to improve metabolic health. This Perspective provides evidence that metabolic effects of milk protein intake have to be regarded in the context of the individual's pre-existing metabolic and exercise status. Milk proteins provide abundant branched-chain amino acids (BCAAs) and glutamine. Plasma BCAAs and glutamine are increased in obesity and insulin resistance, but decrease after gastric bypass surgery resulting in weight loss and improved insulin sensitivity. Milk protein consumption results in postprandial hyperinsulinemia in obese subjects, increases body weight of overweight adolescents and may thus deteriorate pre-existing metabolic disturbances of obese, insulin resistant individuals. PMID:24225036

  2. Metabolic effects of milk protein intake strongly depend on pre-existing metabolic and exercise status

    PubMed Central

    2013-01-01

    Milk protein intake has recently been suggested to improve metabolic health. This Perspective provides evidence that metabolic effects of milk protein intake have to be regarded in the context of the individual’s pre-existing metabolic and exercise status. Milk proteins provide abundant branched-chain amino acids (BCAAs) and glutamine. Plasma BCAAs and glutamine are increased in obesity and insulin resistance, but decrease after gastric bypass surgery resulting in weight loss and improved insulin sensitivity. Milk protein consumption results in postprandial hyperinsulinemia in obese subjects, increases body weight of overweight adolescents and may thus deteriorate pre-existing metabolic disturbances of obese, insulin resistant individuals. PMID:24225036

  3. Relationship between asparagine metabolism and protein concentration in soybean seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The relationship between asparagine metabolism and protein concentration was investigated in soybean seed. Phenotyping of a population of recombinant inbred lines adapted to Illinois confirmed a positive correlation between free asparagine levels in developing seeds and protein concentration at matu...

  4. Gestational protein restriction affects trophoblast differentiation.

    PubMed

    Gao, Haijun; Yallampalli, Uma; Yallampalli, Chandra

    2013-01-01

    Whether and how gestational protein restriction (PR) affects placental development and function remain unknown. To test the hypothesis that PR can affect trophoblast differentiation in mid-and late pregnancy, rats were fed a 20% or an isocaloric 6% protein diet from Day 1 to 14 or 18 of pregnancy and effects of PR on trophoblast differentiation were determined by changes in expressions of marker gene(s) for trophoblast lineages. At Day 18 of pregnancy, PR increased expressions of Esrrb, Id1 andId2 (trophoblast stem cell markers), decreased expressions of Ascl2 (spongiotrophblast cell marker) and Prl2c1 (trophoblast giant cell marker), but did not alter expressions of Gjb3 and Pcdh12(glycogen cell markers) in the junctional zone (JZ). In the labyrinth zone (LZ), PR did not change expressions of Prl2b1 (trophoblast giant cell marker), Gcm1 and Syna (syncytiotrophoblast cell markers), but decrease expression of Ctsq (sinusoidal trophoblast giant cell marker). These results indicate that PR impairs the differentiation of trophoblast stem cell into spongiotrophoblast and trophoblast giant cells in JZ, and formation of sinusoidal trophoblast giant cells in LZ.

  5. 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

  6. 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.

  7. 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.

  8. Chemical Reporter for Visualizing Metabolic Cross-Talk between Carbohydrate Metabolism and Protein Modification

    PubMed Central

    2015-01-01

    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. PMID:25062036

  9. 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.

  10. Boron nutrition affects the carbon metabolism of silver birch seedlings.

    PubMed

    Ruuhola, Teija; Keinänen, Markku; Keski-Saari, Sarita; Lehto, Tarja

    2011-11-01

    Boron (B) is an essential micronutrient whose deficiency is common both in agriculture and in silviculture. Boron deficiency impairs the growth of plants and affects many metabolic processes like carbohydrate metabolism. Boron deficiency and also excess B may decrease the sink demand by decreasing the growth and sugar transport which may lead to the accumulation of carbohydrates and down-regulation of photosynthesis. In this study, we investigated the effects of B nutrition on the soluble and storage carbohydrate concentrations of summer leaves and autumn buds in a deciduous tree species, Betula pendula Roth. In addition, we investigated the changes in the pools of condensed tannins between summer and autumn harvests. One-year-old birch seedlings were fertilized with a complete nutrient solution containing three different levels of B: 0, 30 and 100% of the standard level for complete nutrient solution. Half of the seedlings were harvested after summer period and another half when leaves abscised. The highest B fertilization level (B100) caused an accumulation of starch and a decrease in the concentrations of hexoses (glucose and fructose) in summer leaves, whereas in the B0 seedlings, hexoses (mainly glucose) accumulated and starch decreased. These changes in carbohydrate concentrations might be related to the changes in the sink demand since the autumn growth was the smallest for the B100 seedlings and largest for the B30 seedlings that did not accumulate carbohydrates. The autumn buds of B30 seedlings contained the lowest levels of glucose, glycerol, raffinose and total polyols, which was probably due to the dilution effect of the deposition of other substances like phenols. Condensed tannins accumulated in high amounts in the birch stems during the hardening of seedlings and the largest accumulation was detected in the B30 treatment. Our results suggest that B nutrition of birch seedlings affects the carbohydrate and phenol metabolism and may play an important

  11. 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. PMID:23321473

  12. Protein Quality Control and Metabolism: Bidirectional Control in the Heart

    PubMed Central

    Wang, Zhao V.; Hill, Joseph A.

    2015-01-01

    The prevalence of heart disease, especially heart failure, continues to increase, and cardiovascular disease remains the leading cause of death worldwide. As cardiomyocytes are essentially irreplaceable, protein quality control is pivotal to cellular homeostasis and, ultimately, cardiac performance. Three evolutionarily conserved mechanisms – autophagy, the unfolded protein response, and the ubiquitin-proteasome system– act in concert to degrade misfolded proteins and eliminate defective organelles. Recent advances have revealed that these mechanisms are intimately associated with cellular metabolism. Going forward, comprehensive understanding of the role of protein quality control mechanisms in cardiac pathology will require integration of metabolic pathways and metabolic control. PMID:25651176

  13. Protein Phosphorylation: A Major Switch Mechanism for Metabolic Regulation.

    PubMed

    Humphrey, Sean J; James, David E; Mann, Matthias

    2015-12-01

    Metabolism research is undergoing a renaissance because many diseases are increasingly recognized as being characterized by perturbations in intracellular metabolic regulation. Metabolic changes can be conferred through changes to the expression of metabolic enzymes, the concentrations of substrates or products that govern reaction kinetics, or post-translational modification (PTM) of the proteins that facilitate these reactions. On the 60th anniversary since its discovery, reversible protein phosphorylation is widely appreciated as an essential PTM regulating metabolism. With the ability to quantitatively measure dynamic changes in protein phosphorylation on a global scale - hereafter referred to as phosphoproteomics - we are now entering a new era in metabolism research, with mass spectrometry (MS)-based proteomics at the helm. PMID:26498855

  14. Protein design in systems metabolic engineering for industrial strain development.

    PubMed

    Chen, Zhen; Zeng, An-Ping

    2013-05-01

    Accelerating the process of industrial bacterial host strain development, aimed at increasing productivity, generating new bio-products or utilizing alternative feedstocks, requires the integration of complementary approaches to manipulate cellular metabolism and regulatory networks. Systems metabolic engineering extends the concept of classical metabolic engineering to the systems level by incorporating the techniques used in systems biology and synthetic biology, and offers a framework for the development of the next generation of industrial strains. As one of the most useful tools of systems metabolic engineering, protein design allows us to design and optimize cellular metabolism at a molecular level. Here, we review the current strategies of protein design for engineering cellular synthetic pathways, metabolic control systems and signaling pathways, and highlight the challenges of this subfield within the context of systems metabolic engineering.

  15. Leucine and Protein Metabolism in Obese Zucker Rats

    PubMed Central

    She, Pengxiang; Olson, Kristine C.; Kadota, Yoshihiro; Inukai, Ayami; Shimomura, Yoshiharu; Hoppel, Charles L.; Adams, Sean H.; Kawamata, Yasuko; Matsumoto, Hideki; Sakai, Ryosei; Lang, Charles H.; Lynch, Christopher J.

    2013-01-01

    Branched-chain amino acids (BCAAs) are circulating nutrient signals for protein accretion, however, they increase in obesity and elevations appear to be prognostic of diabetes. To understand the mechanisms whereby obesity affects BCAAs and protein metabolism, we employed metabolomics and measured rates of [1-14C]-leucine metabolism, tissue-specific protein synthesis and branched-chain keto-acid (BCKA) dehydrogenase complex (BCKDC) activities. Male obese Zucker rats (11-weeks old) had increased body weight (BW, 53%), liver (107%) and fat (∼300%), but lower plantaris and gastrocnemius masses (−21–24%). Plasma BCAAs and BCKAs were elevated 45–69% and ∼100%, respectively, in obese rats. Processes facilitating these rises appeared to include increased dietary intake (23%), leucine (Leu) turnover and proteolysis [35% per g fat free mass (FFM), urinary markers of proteolysis: 3-methylhistidine (183%) and 4-hydroxyproline (766%)] and decreased BCKDC per g kidney, heart, gastrocnemius and liver (−47–66%). A process disposing of circulating BCAAs, protein synthesis, was increased 23–29% by obesity in whole-body (FFM corrected), gastrocnemius and liver. Despite the observed decreases in BCKDC activities per gm tissue, rates of whole-body Leu oxidation in obese rats were 22% and 59% higher normalized to BW and FFM, respectively. Consistently, urinary concentrations of eight BCAA catabolism-derived acylcarnitines were also elevated. The unexpected increase in BCAA oxidation may be due to a substrate effect in liver. Supporting this idea, BCKAs were elevated more in liver (193–418%) than plasma or muscle, and per g losses of hepatic BCKDC activities were completely offset by increased liver mass, in contrast to other tissues. In summary, our results indicate that plasma BCKAs may represent a more sensitive metabolic signature for obesity than BCAAs. Processes supporting elevated BCAA]BCKAs in the obese Zucker rat include increased dietary intake, Leu and

  16. Black leaf streak disease affects starch metabolism in banana fruit.

    PubMed

    Saraiva, Lorenzo de Amorim; Castelan, Florence Polegato; Shitakubo, Renata; Hassimotto, Neuza Mariko Aymoto; Purgatto, Eduardo; Chillet, Marc; Cordenunsi, Beatriz Rosana

    2013-06-12

    Black leaf streak disease (BLSD), also known as black sigatoka, represents the main foliar disease in Brazilian banana plantations. In addition to photosynthetic leaf area losses and yield losses, this disease causes an alteration in the pre- and postharvest behavior of the fruit. The aim of this work was to investigate the starch metabolism of fruits during fruit ripening from plants infected with BLSD by evaluating carbohydrate content (i.e., starch, soluble sugars, oligosaccharides, amylose), phenolic compound content, phytohormones, enzymatic activities (i.e., starch phosphorylases, α- and β-amylase), and starch granules. The results indicated that the starch metabolism in banana fruit ripening is affected by BLSD infection. Fruit from infested plots contained unusual amounts of soluble sugars in the green stage and smaller starch granules and showed a different pattern of superficial degradation. Enzymatic activities linked to starch degradation were also altered by the disease. Moreover, the levels of indole-acetic acid and phenolic compounds indicated an advanced fruit physiological age for fruits from infested plots. PMID:23692371

  17. Ethanol Metabolism Modifies Hepatic Protein Acylation in Mice

    PubMed Central

    Fritz, Kristofer S.; Green, Michelle F.; Petersen, Dennis R.; Hirschey, Matthew D.

    2013-01-01

    Mitochondrial protein acetylation increases in response to chronic ethanol ingestion in mice, and is thought to reduce mitochondrial function and contribute to the pathogenesis of alcoholic liver disease. The mitochondrial deacetylase SIRT3 regulates the acetylation status of several mitochondrial proteins, including those involved in ethanol metabolism. The newly discovered desuccinylase activity of the mitochondrial sirtuin SIRT5 suggests that protein succinylation could be an important post-translational modification regulating mitochondrial metabolism. To assess the possible role of protein succinylation in ethanol metabolism, we surveyed hepatic sub-cellular protein fractions from mice fed a control or ethanol-supplemented diet for succinyl-lysine, as well as acetyl-, propionyl-, and butyryl-lysine post-translational modifications. We found mitochondrial protein propionylation increases, similar to mitochondrial protein acetylation. In contrast, mitochondrial protein succinylation is reduced. These mitochondrial protein modifications appear to be primarily driven by ethanol metabolism, and not by changes in mitochondrial sirtuin levels. Similar trends in acyl modifications were observed in the nucleus. However, comparatively fewer acyl modifications were observed in the cytoplasmic or the microsomal compartments, and were generally unchanged by ethanol metabolism. Using a mass spectrometry proteomics approach, we identified several candidate acetylated, propionylated, and succinylated proteins, which were enriched using antibodies against each modification. Additionally, we identified several acetyl and propionyl lysine residues on the same sites for a number of proteins and supports the idea of the overlapping nature of lysine-specific acylation. Thus, we show that novel post-translational modifications are present in hepatic mitochondrial, nuclear, cytoplasmic, and microsomal compartments and ethanol ingestion, and its associated metabolism, induce specific

  18. 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

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

    PubMed

    Yang, Yu-Xiang; Mu, Chun-Long; Luo, Zhen; Zhu, Wei-Yun

    2016-02-01

    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

  20. BCL-2 family proteins as regulators of mitochondria metabolism.

    PubMed

    Gross, Atan

    2016-08-01

    The BCL-2 family proteins are major regulators of apoptosis, and one of their major sites of action are the mitochondria. Mitochondria are the cellular hubs for metabolism and indeed selected BCL-2 family proteins also possess roles related to mitochondria metabolism and dynamics. Here we discuss the link between mitochondrial metabolism/dynamics and the fate of stem cells, with an emphasis on the role of the BID-MTCH2 pair in regulating this link. We also discuss the possibility that BCL-2 family proteins act as metabolic sensors/messengers coming on and off of mitochondria to "sample" the cytosol and provide the mitochondria with up-to-date metabolic information. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi.

  1. Protein Molecular Structures, Protein SubFractions, and Protein Availability Affected by Heat Processing: A Review

    SciTech Connect

    Yu,P.

    2007-01-01

    The utilization and availability of protein depended on the types of protein and their specific susceptibility to enzymatic hydrolysis (inhibitory activities) in the gastrointestine and was highly associated with protein molecular structures. Studying internal protein structure and protein subfraction profiles leaded to an understanding of the components that make up a whole protein. An understanding of the molecular structure of the whole protein was often vital to understanding its digestive behavior and nutritive value in animals. In this review, recently obtained information on protein molecular structural effects of heat processing was reviewed, in relation to protein characteristics affecting digestive behavior and nutrient utilization and availability. The emphasis of this review was on (1) using the newly advanced synchrotron technology (S-FTIR) as a novel approach to reveal protein molecular chemistry affected by heat processing within intact plant tissues; (2) revealing the effects of heat processing on the profile changes of protein subfractions associated with digestive behaviors and kinetics manipulated by heat processing; (3) prediction of the changes of protein availability and supply after heat processing, using the advanced DVE/OEB and NRC-2001 models, and (4) obtaining information on optimal processing conditions of protein as intestinal protein source to achieve target values for potential high net absorbable protein in the small intestine. The information described in this article may give better insight in the mechanisms involved and the intrinsic protein molecular structural changes occurring upon processing.

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

    PubMed

    Soare, Andreea; Weiss, Edward P; Holloszy, John O; Fontana, Luigi

    2013-09-01

    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.

  3. MANET: tracing evolution of protein architecture in metabolic networks

    PubMed Central

    Kim, Hee Shin; Mittenthal, Jay E; Caetano-Anollés, Gustavo

    2006-01-01

    Background Cellular metabolism can be characterized by networks of enzymatic reactions and transport processes capable of supporting cellular life. Our aim is to find evolutionary patterns and processes embedded in the architecture and function of modern metabolism, using information derived from structural genomics. Description The Molecular Ancestry Network (MANET) project traces evolution of protein architecture in biomolecular networks. We describe metabolic MANET, a database that links information in the Structural Classification of Proteins (SCOP), the Kyoto Encyclopedia of Genes and Genomes (KEGG), and phylogenetic reconstructions depicting the evolution of protein fold architecture. Metabolic MANET literally 'paints' the ancestries of enzymes derived from rooted phylogenomic trees directly onto over one hundred metabolic subnetworks, enabling the study of evolutionary patterns at global and local levels. An initial analysis of painted subnetworks reveals widespread enzymatic recruitment and an early origin of amino acid metabolism. Conclusion MANET maps evolutionary relationships directly and globally onto biological networks, and can generate and test hypotheses related to evolution of metabolism. We anticipate its use in the study of other networks, such as signaling and other protein-protein interaction networks. PMID:16854231

  4. Spastin binds to lipid droplets and affects lipid metabolism.

    PubMed

    Papadopoulos, Chrisovalantis; Orso, Genny; Mancuso, Giuseppe; Herholz, Marija; Gumeni, Sentiljana; Tadepalle, Nimesha; Jüngst, Christian; Tzschichholz, Anne; Schauss, Astrid; Höning, Stefan; Trifunovic, Aleksandra; Daga, Andrea; Rugarli, Elena I

    2015-04-01

    Mutations in SPAST, encoding spastin, are the most common cause of autosomal dominant hereditary spastic paraplegia (HSP). HSP is characterized by weakness and spasticity of the lower limbs, owing to progressive retrograde degeneration of the long corticospinal axons. Spastin is a conserved microtubule (MT)-severing protein, involved in processes requiring rearrangement of the cytoskeleton in concert to membrane remodeling, such as neurite branching, axonal growth, midbody abscission, and endosome tubulation. Two isoforms of spastin are synthesized from alternative initiation codons (M1 and M87). We now show that spastin-M1 can sort from the endoplasmic reticulum (ER) to pre- and mature lipid droplets (LDs). A hydrophobic motif comprised of amino acids 57 through 86 of spastin was sufficient to direct a reporter protein to LDs, while mutation of arginine 65 to glycine abolished LD targeting. Increased levels of spastin-M1 expression reduced the number but increased the size of LDs. Expression of a mutant unable to bind and sever MTs caused clustering of LDs. Consistent with these findings, ubiquitous overexpression of Dspastin in Drosophila led to bigger and less numerous LDs in the fat bodies and increased triacylglycerol levels. In contrast, Dspastin overexpression increased LD number when expressed specifically in skeletal muscles or nerves. Downregulation of Dspastin and expression of a dominant-negative variant decreased LD number in Drosophila nerves, skeletal muscle and fat bodies, and reduced triacylglycerol levels in the larvae. Moreover, we found reduced amount of fat stores in intestinal cells of worms in which the spas-1 homologue was either depleted by RNA interference or deleted. Taken together, our data uncovers an evolutionarily conserved role of spastin as a positive regulator of LD metabolism and open up the possibility that dysfunction of LDs in axons may contribute to the pathogenesis of HSP.

  5. Dietary Proteins as Determinants of Metabolic and Physiologic Functions of the Gastrointestinal Tract

    PubMed Central

    Jahan-Mihan, Alireza; Luhovyy, Bohdan L.; Khoury, Dalia El; Anderson, G. Harvey

    2011-01-01

    Dietary proteins elicit a wide range of nutritional and biological functions. Beyond their nutritional role as the source of amino acids for protein synthesis, they are instrumental in the regulation of food intake, glucose and lipid metabolism, blood pressure, bone metabolism and immune function. The interaction of dietary proteins and their products of digestion with the regulatory functions of the gastrointestinal (GI) tract plays a dominant role in determining the physiological properties of proteins. The site of interaction is widespread, from the oral cavity to the colon. The characteristics of proteins that influence their interaction with the GI tract in a source-dependent manner include their physico-chemical properties, their amino acid composition and sequence, their bioactive peptides, their digestion kinetics and also the non-protein bioactive components conjugated with them. Within the GI tract, these products affect several regulatory functions by interacting with receptors releasing hormones, affecting stomach emptying and GI transport and absorption, transmitting neural signals to the brain, and modifying the microflora. This review discusses the interaction of dietary proteins during digestion and absorption with the physiological and metabolic functions of the GI tract, and illustrates the importance of this interaction in the regulation of amino acid, glucose, lipid metabolism, and food intake. PMID:22254112

  6. Analysis of soybean root proteins affected by gibberellic acid treatment under flooding stress.

    PubMed

    Oh, Myeong Won; Nanjo, Yohei; Komatsu, Setsuko

    2014-01-01

    Flooding is a serious abiotic stress for soybean because it restricts growth and reduces grain yields. To investigate the effect of gibberellic acid (GA) on soybean under flooding stress, root proteins were analyzed using a gel-free proteomic technique. Proteins were extracted from the roots of 4-days-old soybean seedlings exposed to flooding stress in the presence and absence of exogenous GA3 for 2 days. A total of 307, 324, and 250 proteins were identified from untreated, and flooding-treated soybean seedlings without or with GA3, respectively. Secondary metabolism- and cell-related proteins, and proteins involved in protein degradation/synthesis were decreased by flooding stress; however, the levels of these proteins were restored by GA3 supplementation under flooding. Fermentation- and cell wall-related proteins were not affected by GA3 supplementation. Furthermore, putative GA-responsive proteins, which were identified by the presence of a GA-responsive element in the promoter region, were less abundant by flooding stress; however, these proteins were more abundant by GA3 supplementation under flooding. Taken together, these results suggest that GA3 affects the abundance of proteins involved in secondary metabolism, cell cycle, and protein degradation/synthesis in soybeans under flooding stress. PMID:24702262

  7. Evolution of biomolecular networks: lessons from metabolic and protein interactions.

    PubMed

    Yamada, Takuji; Bork, Peer

    2009-11-01

    Despite only becoming popular at the beginning of this decade, biomolecular networks are now frameworks that facilitate many discoveries in molecular biology. The nodes of these networks are usually proteins (specifically enzymes in metabolic networks), whereas the links (or edges) are their interactions with other molecules. These networks are made up of protein-protein interactions or enzyme-enzyme interactions through shared metabolites in the case of metabolic networks. Evolutionary analysis has revealed that changes in the nodes and links in protein-protein interaction and metabolic networks are subject to different selection pressures owing to distinct topological features. However, many evolutionary constraints can be uncovered only if temporal and spatial aspects are included in the network analysis.

  8. Radioactive Lysine in Protein Metabolism Studies

    DOE R&D Accomplishments Database

    Miller, L. L.; Bale, W. F.; Yuile, C. L.; Masters, R. E.; Tishkoff, G. H.; Whipple,, G. H.

    1950-01-09

    Studies of incorporation of DL-lysine in various body proteins of the dog; the time course of labeled blood proteins; and apparent rate of disappearance of labeled plasma proteins for comparison of behavior of the plasma albumin and globulin fractions; shows more rapid turn over of globulin fraction.

  9. Protein and amino acid metabolism and requirements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proteins are the major structural and functional components of all cells of the body. Enzymes, membrane carriers, blood transport molecules, intracellular matrix, and even hair and fingernails are proteins, as are many hormones. Proteins also constitute a major portion of all membranes, and the cons...

  10. Ceramide metabolism is affected by obesity and diabetes in human adipose tissue.

    PubMed

    Błachnio-Zabielska, A U; Pułka, M; Baranowski, M; Nikołajuk, A; Zabielski, P; Górska, M; Górski, J

    2012-02-01

    Ceramide is involved in development of insulin resistance. However, there are no data on ceramide metabolism in human adipose tissue. The aim of our study was to examine sphingolipid metabolism in fat tissue from obese nondiabetic (n = 11), obese diabetic (n = 11), and lean nondiabetic (n = 8) subjects. The content of ceramide (Cer), dihydroceramide (dhCer), sphingosine (SPH), sphinganine (SPA), sphingosine-1-phosphate (S1P; pmol/mg of protein), the expression (mRNA) and activity of key enzymes responsible for Cer metabolism: serine palmitoyltransferase (SPT), neutral and acidic sphingomyelinase (nSMase and aSMase, respectively), and neutral and acidic ceramidase (nCDase and aCDase, respectively) were examined in human adipose tissue. The contents of SPA and Cer were significantly lower whereas the content of dhCer was higher in both obese groups than the respective values in the lean subjects. The expression of examined enzymes was elevated in both obese groups. The SPT and CDases activity increased whereas aSMase activity deceased in both obese groups. We have found correlation between adipose tissue Cer content and plasma adiponectin concentration (r = 0.69, P < 0.001) and negative correlation between total Cer content and HOMA-IR index (homeostasis model of insulin resistance) (r = -0.67, P < 0.001). We have found that both obesity and diabetes affected pathways of sphingolipid metabolism in the adipose tissue.

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

    PubMed Central

    Caron, Alexandre; Labbé, Sébastien M.; Mouchiroud, Mathilde; Huard, Renaud; Richard, Denis

    2016-01-01

    We have recently demonstrated that specific overexpression of DEP-domain containing mTOR-interacting protein (DEPTOR) in the mediobasal hypothalamus (MBH) protects mice against high-fat diet-induced obesity, revealing DEPTOR as a significant contributor to energy balance regulation. On the basis of evidence that DEPTOR is expressed in the proopiomelanocortin (POMC) neurons of the MBH, the present study aimed to investigate whether these neurons mediate the metabolic effects of DEPTOR. Here, we report that specific DEPTOR overexpression in POMC neurons does not recapitulate any of the phenotypes observed when the protein was overexpressed in the MBH. Unlike the previous model, mice overexpressing DEPTOR only in POMC neurons 1) did not show differences in feeding behavior, 2) did not exhibit changes in locomotion activity and oxygen consumption, 3) did not show an improvement in systemic glucose metabolism, and 4) were not resistant to high-fat diet-induced obesity. These results support the idea that other neuronal populations are responsible for these phenotypes. Nonetheless, we observed a mild elevation in fasting blood glucose, insulin resistance, and alterations in liver glucose and lipid homeostasis in mice overexpressing DEPTOR in POMC neurons. Taken together, these results show that DEPTOR overexpression in POMC neurons does not affect energy balance regulation but could modulate metabolism through a brain-liver connection. PMID:27097662

  12. C282Y-HFE Gene Variant Affects Cholesterol Metabolism in Human Neuroblastoma Cells

    PubMed Central

    Ali-Rahmani, Fatima; Huang, Michael A.; Schengrund, C.-L.; Connor, James R.; Lee, Sang Y.

    2014-01-01

    Although disruptions in the maintenance of iron and cholesterol metabolism have been implicated in several cancers, the association between variants in the HFE gene that is associated with cellular iron uptake and cholesterol metabolism has not been studied. The C282Y-HFE variant is a risk factor for different cancers, is known to affect sphingolipid metabolism, and to result in increased cellular iron uptake. The effect of this variant on cholesterol metabolism and its possible relevance to cancer phenotype was investigated using wild type (WT) and C282Y-HFE transfected human neuroblastoma SH-SY5Y cells. Expression of C282Y-HFE in SH-SY5Y cells resulted in a significant increase in total cholesterol as well as increased transcription of a number of genes involved in its metabolism compared to cells expressing WT-HFE. The marked increase in expression of NPC1L1 relative to that of most other genes, was accompanied by a significant increase in expression of NPC1, a protein that functions in cholesterol uptake by cells. Because inhibitors of cholesterol metabolism have been proposed to be beneficial for treating certain cancers, their effect on the viability of C282Y-HFE neuroblastoma cells was ascertained. C282Y-HFE cells were significantly more sensitive than WT-HFE cells to U18666A, an inhibitor of desmosterol Δ24-reductase the enzyme catalyzing the last step in cholesterol biosynthesis. This was not seen for simvastatin, ezetimibe, or a sphingosine kinase inhibitor. These studies indicate that cancers presenting in carriers of the C282Y-HFE allele might be responsive to treatment designed to selectively reduce cholesterol content in their tumor cells. PMID:24533143

  13. Integrated Metabolomics, Transcriptomics and Proteomics Identifies Metabolic Pathways Affected by Anaplasma phagocytophilum Infection in Tick Cells.

    PubMed

    Villar, Margarita; Ayllón, Nieves; Alberdi, Pilar; Moreno, Andrés; Moreno, María; Tobes, Raquel; Mateos-Hernández, Lourdes; Weisheit, Sabine; Bell-Sakyi, Lesley; de la Fuente, José

    2015-12-01

    Anaplasma phagocytophilum is an emerging zoonotic pathogen that causes human granulocytic anaplasmosis. These intracellular bacteria establish infection by affecting cell function in both the vertebrate host and the tick vector, Ixodes scapularis. Previous studies have characterized the tick transcriptome and proteome in response to A. phagocytophilum infection. However, in the postgenomic era, the integration of omics datasets through a systems biology approach allows network-based analyses to describe the complexity and functionality of biological systems such as host-pathogen interactions and the discovery of new targets for prevention and control of infectious diseases. This study reports the first systems biology integration of metabolomics, transcriptomics, and proteomics data to characterize essential metabolic pathways involved in the tick response to A. phagocytophilum infection. The ISE6 tick cells used in this study constitute a model for hemocytes involved in pathogen infection and immune response. The results showed that infection affected protein processing in endoplasmic reticulum and glucose metabolic pathways in tick cells. These results supported tick-Anaplasma co-evolution by providing new evidence of how tick cells limit pathogen infection, while the pathogen benefits from the tick cell response to establish infection. Additionally, ticks benefit from A. phagocytophilum infection by increasing survival while pathogens guarantee transmission. The results suggested that A. phagocytophilum induces protein misfolding to limit the tick cell response and facilitate infection but requires protein degradation to prevent ER stress and cell apoptosis to survive in infected cells. Additionally, A. phagocytophilum may benefit from the tick cell's ability to limit bacterial infection through PEPCK inhibition leading to decreased glucose metabolism, which also results in the inhibition of cell apoptosis that increases infection of tick cells. These results

  14. Effect of dietary protein restriction on renal ammonia metabolism.

    PubMed

    Lee, Hyun-Wook; Osis, Gunars; Handlogten, Mary E; Guo, Hui; Verlander, Jill W; Weiner, I David

    2015-06-15

    Dietary protein restriction has multiple benefits in kidney disease. Because protein intake is a major determinant of endogenous acid production, it is important that net acid excretion change in parallel during protein restriction. Ammonia is the primary component of net acid excretion, and inappropriate ammonia excretion can lead to negative nitrogen balance. Accordingly, we examined ammonia excretion in response to protein restriction and then we determined the molecular mechanism of the changes observed. Wild-type C57Bl/6 mice fed a 20% protein diet and then changed to 6% protein developed an 85% reduction in ammonia excretion within 2 days, which persisted during a 10-day study. The expression of multiple proteins involved in renal ammonia metabolism was altered, including the ammonia-generating enzymes phosphate-dependent glutaminase (PDG) and phosphoenolpyruvate carboxykinase (PEPCK) and the ammonia-metabolizing enzyme glutamine synthetase. Rhbg, an ammonia transporter, increased in expression in the inner stripe of outer medullary collecting duct intercalated cell (OMCDis-IC). However, collecting duct-specific Rhbg deletion did not alter the response to protein restriction. Rhcg deletion did not alter ammonia excretion in response to dietary protein restriction. These results indicate 1) dietary protein restriction decreases renal ammonia excretion through coordinated regulation of multiple components of ammonia metabolism; 2) increased Rhbg expression in the OMCDis-IC may indicate a biological role in addition to ammonia transport; and 3) Rhcg expression is not necessary to decrease ammonia excretion during dietary protein restriction. PMID:25925252

  15. Effect of dietary protein restriction on renal ammonia metabolism.

    PubMed

    Lee, Hyun-Wook; Osis, Gunars; Handlogten, Mary E; Guo, Hui; Verlander, Jill W; Weiner, I David

    2015-06-15

    Dietary protein restriction has multiple benefits in kidney disease. Because protein intake is a major determinant of endogenous acid production, it is important that net acid excretion change in parallel during protein restriction. Ammonia is the primary component of net acid excretion, and inappropriate ammonia excretion can lead to negative nitrogen balance. Accordingly, we examined ammonia excretion in response to protein restriction and then we determined the molecular mechanism of the changes observed. Wild-type C57Bl/6 mice fed a 20% protein diet and then changed to 6% protein developed an 85% reduction in ammonia excretion within 2 days, which persisted during a 10-day study. The expression of multiple proteins involved in renal ammonia metabolism was altered, including the ammonia-generating enzymes phosphate-dependent glutaminase (PDG) and phosphoenolpyruvate carboxykinase (PEPCK) and the ammonia-metabolizing enzyme glutamine synthetase. Rhbg, an ammonia transporter, increased in expression in the inner stripe of outer medullary collecting duct intercalated cell (OMCDis-IC). However, collecting duct-specific Rhbg deletion did not alter the response to protein restriction. Rhcg deletion did not alter ammonia excretion in response to dietary protein restriction. These results indicate 1) dietary protein restriction decreases renal ammonia excretion through coordinated regulation of multiple components of ammonia metabolism; 2) increased Rhbg expression in the OMCDis-IC may indicate a biological role in addition to ammonia transport; and 3) Rhcg expression is not necessary to decrease ammonia excretion during dietary protein restriction.

  16. Comparative genomics and evolution of proteins involved in RNA metabolism

    PubMed Central

    Anantharaman, Vivek; Koonin, Eugene V.; Aravind, L.

    2002-01-01

    RNA metabolism, broadly defined as the compendium of all processes that involve RNA, including transcription, processing and modification of transcripts, translation, RNA degradation and its regulation, is the central and most evolutionarily conserved part of cell physiology. A comprehensive, genome-wide census of all enzymatic and non-enzymatic protein domains involved in RNA metabolism was conducted by using sequence profile analysis and structural comparisons. Proteins related to RNA metabolism comprise from 3 to 11% of the complete protein repertoire in bacteria, archaea and eukaryotes, with the greatest fraction seen in parasitic bacteria with small genomes. Approximately one-half of protein domains involved in RNA metabolism are present in most, if not all, species from all three primary kingdoms and are traceable to the last universal common ancestor (LUCA). The principal features of LUCA’s RNA metabolism system were reconstructed by parsimony-based evolutionary analysis of all relevant groups of orthologous proteins. This reconstruction shows that LUCA possessed not only the basal translation system, but also the principal forms of RNA modification, such as methylation, pseudouridylation and thiouridylation, as well as simple mechanisms for polyadenylation and RNA degradation. Some of these ancient domains form paralogous groups whose evolution can be traced back in time beyond LUCA, towards low-specificity proteins, which probably functioned as cofactors for ribozymes within the RNA world framework. The main lineage-specific innovations of RNA metabolism systems were identified. The most notable phase of innovation in RNA metabolism coincides with the advent of eukaryotes and was brought about by the merge of the archaeal and bacterial systems via mitochondrial endosymbiosis, but also involved emergence of several new, eukaryote-specific RNA-binding domains. Subsequent, vast expansions of these domains mark the origin of alternative splicing in animals

  17. Gel-free proteomic analysis of soybean root proteins affected by calcium under flooding stress

    PubMed Central

    Oh, MyeongWon; Nanjo, Yohei; Komatsu, Setsuko

    2014-01-01

    Soybean is sensitive to flooding stress and exhibits reduced growth under flooding conditions. To better understand the flooding-responsive mechanisms of soybean, the effect of exogenous calcium on flooding-stressed soybeans was analyzed using proteomic technique. An increase in exogenous calcium levels enhanced soybean root elongation and suppressed the cell death of root tip under flooding stress. Proteins were extracted from the roots of 4-day-old soybean seedlings exposed to flooding stress without or with calcium for 2 days and analyzed using gel-free proteomic technique. Proteins involved in protein degradation/synthesis/posttranslational modification, hormone/cell wall metabolisms, and DNA synthesis were decreased by flooding stress; however, their reductions were recovered by calcium treatment. Development, lipid metabolism, and signaling-related proteins were increased in soybean roots when calcium was supplied under flooding stress. Fermentation and glycolysis-related proteins were increased in response to flooding; however, these proteins were not affected by calcium supplementation. Furthermore, urease and copper chaperone proteins exhibited similar profiles in 4-day-old untreated soybeans and 4-day-old soybeans exposed to flooding for 2 days in the presence of calcium. These results suggest that calcium might affect the cell wall/hormone metabolisms, protein degradation/synthesis, and DNA synthesis in soybean roots under flooding stress. PMID:25368623

  18. Leptin expression affects metabolic rate in zebrafish embryos (D. rerio).

    PubMed

    Dalman, Mark R; Liu, Qin; King, Mason D; Bagatto, Brian; Londraville, Richard L

    2013-01-01

    We used antisense morpholino oligonucleotide technology to knockdown leptin-(A) gene expression in developing zebrafish embryos and measured its effects on metabolic rate and cardiovascular function. Using two indicators of metabolic rate, oxygen consumption was significantly lower in leptin morphants early in development [<48 hours post-fertilization (hpf)], while acid production was significantly lower in morphants later in development (>48 hpf). Oxygen utilization rates in <48 hpf embryos and acid production in 72 hpf embryos could be rescued to that of wildtype embryos by recombinant leptin coinjected with antisense morpholino. Leptin is established to influence metabolic rate in mammals, and these data suggest leptin signaling also influences metabolic rate in fishes.

  19. Protein and amino acid metabolism in the human newborn.

    PubMed

    Kalhan, Satish C; Bier, Dennis M

    2008-01-01

    Birth and adaptation to extrauterine life involve major shifts in the protein and energy metabolism of the human newborn. These include a shift from a state of continuous supply of nutrients including amino acids from the mother to cyclic periodic oral intake, a change in the redox state of organs, thermogenesis, and a significant change in the mobilization and use of oxidative substrates. The development of safe, stable isotopic tracer methods has allowed the study of protein and amino acid metabolism not only in the healthy newborn but also in those born prematurely and of low birth weight. These studies have identified the unique and quantitative aspects of amino acid/protein metabolism in the neonate, thus contributing to rational nutritional care of these babies. The present review summarizes the contemporary data on some of the significant developments in essential and dispensable amino acids and their relationship to overall protein metabolism. Specifically, the recent data of kinetics of leucine, phenylalanine, glutamine, sulfur amino acid, and threonine and their relation to whole-body protein turnover are presented. Finally, the physiological rationale and the impact of nutrient (amino acids) interventions on the dynamics of protein metabolism are discussed.

  20. Environmentally Relevant Dose of Bisphenol A Does Not Affect Lipid Metabolism and Has No Synergetic or Antagonistic Effects on Genistein’s Beneficial Roles on Lipid Metabolism

    PubMed Central

    Fan, Ying; Li, Hongyu; Zhao, Nana; Yang, Huiqin; Ye, Xiaolei; He, Dongliang; Yang, Hui; Jin, Xin; Tian, Chong; Ying, Chenjiang

    2016-01-01

    Both bisphenol A (BPA, an endocrine disrupting chemicals) and genistein (a phytoestrogen mainly derived from leguminosae) are able to bind to estrogen receptors, but they are considered to have different effects on metabolic syndrome, surprisingly. We here investigate the effects of an environmentally relevant dose of BPA alone and the combined effects with genistein on lipid metabolism in rats. Eight groups of adult male Wistar rats, fed with either standard chow diet or high-fat diet, were treated with BPA (50μg/kg/day), genistein (10mg/kg/day), and BPA plus genistein for 35 weeks, respectively. Metabolic parameters in serum and liver were determined; the hematoxylin/eosin and oil Red O staining were used to observe liver histologically; gene expressions related to hepatic lipid metabolism were analyzed by Real-time PCR; protein expressions of PPARγ, PPARα and LC3 in liver were analyzed by western blotting. No difference of body weight gain, total energy intake, liver weight/body weight or body fat percentage in both STD- and HFD-fed sub-groups was observed after treatment with BPA, genistein, or BPA plus genistein (P>0.05). Genistein alleviated lipid metabolism disorder and decreased the mRNA and protein expression of PPARγ (P<0.05), and increased the protein expression of LC3II (P<0.05) in liver of HFD-fed rats. However, BPA treatment had no effect on lipid metabolism in rats alone (P>0.05) or combined with genistein. Our findings suggest that long-term environmentally relevant dose of BPA did not affect lipid metabolism, and had no synergetic or antagonistic roles on genistein’s beneficial function on hepatic lipid metabolism. PMID:27171397

  1. Environmentally Relevant Dose of Bisphenol A Does Not Affect Lipid Metabolism and Has No Synergetic or Antagonistic Effects on Genistein's Beneficial Roles on Lipid Metabolism.

    PubMed

    Ding, Shibin; Zuo, Xuezhi; Fan, Ying; Li, Hongyu; Zhao, Nana; Yang, Huiqin; Ye, Xiaolei; He, Dongliang; Yang, Hui; Jin, Xin; Tian, Chong; Ying, Chenjiang

    2016-01-01

    Both bisphenol A (BPA, an endocrine disrupting chemicals) and genistein (a phytoestrogen mainly derived from leguminosae) are able to bind to estrogen receptors, but they are considered to have different effects on metabolic syndrome, surprisingly. We here investigate the effects of an environmentally relevant dose of BPA alone and the combined effects with genistein on lipid metabolism in rats. Eight groups of adult male Wistar rats, fed with either standard chow diet or high-fat diet, were treated with BPA (50μg/kg/day), genistein (10mg/kg/day), and BPA plus genistein for 35 weeks, respectively. Metabolic parameters in serum and liver were determined; the hematoxylin/eosin and oil Red O staining were used to observe liver histologically; gene expressions related to hepatic lipid metabolism were analyzed by Real-time PCR; protein expressions of PPARγ, PPARα and LC3 in liver were analyzed by western blotting. No difference of body weight gain, total energy intake, liver weight/body weight or body fat percentage in both STD- and HFD-fed sub-groups was observed after treatment with BPA, genistein, or BPA plus genistein (P>0.05). Genistein alleviated lipid metabolism disorder and decreased the mRNA and protein expression of PPARγ (P<0.05), and increased the protein expression of LC3II (P<0.05) in liver of HFD-fed rats. However, BPA treatment had no effect on lipid metabolism in rats alone (P>0.05) or combined with genistein. Our findings suggest that long-term environmentally relevant dose of BPA did not affect lipid metabolism, and had no synergetic or antagonistic roles on genistein's beneficial function on hepatic lipid metabolism. PMID:27171397

  2. Role of a liver fatty acid-binding protein gene in lipid metabolism in chicken hepatocytes.

    PubMed

    Gao, G L; Na, W; Wang, Y X; Zhang, H F; Li, H; Wang, Q G

    2015-01-01

    This study investigated the role of the chicken liver fatty acid-binding protein (L-FABP) gene in lipid metabolism in hepatocytes, and the regulatory relationships between L-FABP and genes related to lipid metabolism. The short hairpin RNA (shRNA) interference vector with L-FABP and an eukaryotic expression vector were used. Chicken hepatocytes were subjected to shRNA-mediated knockdown or L-FABP cDNA overexpression. Expression levels of lipid metabolism-related genes and biochemical parameters were detected 24, 36, 48, 60, and 72 h after transfection with the interference or overexpression plasmids for L-FABP, PPARα and L-BABP expression levels, and the total amount of cholesterol, were significantly affected by L-FABP expression. L-FABP may affect lipid metabolism by regulating PPARα and L-BABP in chicken hepatocytes. PMID:25966259

  3. Role of a liver fatty acid-binding protein gene in lipid metabolism in chicken hepatocytes.

    PubMed

    Gao, G L; Na, W; Wang, Y X; Zhang, H F; Li, H; Wang, Q G

    2015-01-01

    This study investigated the role of the chicken liver fatty acid-binding protein (L-FABP) gene in lipid metabolism in hepatocytes, and the regulatory relationships between L-FABP and genes related to lipid metabolism. The short hairpin RNA (shRNA) interference vector with L-FABP and an eukaryotic expression vector were used. Chicken hepatocytes were subjected to shRNA-mediated knockdown or L-FABP cDNA overexpression. Expression levels of lipid metabolism-related genes and biochemical parameters were detected 24, 36, 48, 60, and 72 h after transfection with the interference or overexpression plasmids for L-FABP, PPARα and L-BABP expression levels, and the total amount of cholesterol, were significantly affected by L-FABP expression. L-FABP may affect lipid metabolism by regulating PPARα and L-BABP in chicken hepatocytes.

  4. Isotopic labeling affects 1,25-dihydroxyvitamin D metabolism

    SciTech Connect

    Halloran, B.P.; Bikle, D.D.; Castro, M.E.; Gee, E.

    1989-02-07

    Isotope substitution can change the biochemical properties of vitamin D. To determine the effect of substituting 3H for 1H on the metabolism of 1,25(OH)2D3, we measured the metabolic clearance rate and renal metabolism of unlabeled and 3H-labeled 1,25(OH)2D3. Substitution of 3H for 1H on carbons 26 and 27 (1,25(OH)2(26,27(n)-3H)D3) or on carbons 23 and 24 (1,25(OH)2(23,24(n)-3H)D3) reduced the in vivo metabolic clearance rate of 1,25(OH)2D3 by 36% and 37%, respectively, and reduced the in vitro renal catabolism of 1,25(OH)2D3 by 11% and 54%, respectively. Substitutions of 3H for 1H on carbons 23 and 24 as opposed to carbons 26 and 27 reduced conversion of (3H)1,25(OH)2D3 to (3H)1,24,25(OH)2D3 by 25% and to putative 24-oxo-1,23,25-dihydroxyvitamin D3 by 1600%. These results indicate that substitution of 3H for 1H on carbons 26 and 27 or on carbons 23 and 24 can reduce the metabolic clearance rate and in vitro metabolism of 1,25(OH)2D3 and quantitatively alter the pattern of metabolic products produced.

  5. Protein deacetylation by SIRT1: an emerging key post-translational modification in metabolic regulation.

    PubMed

    Yu, Jiujiu; Auwerx, Johan

    2010-07-01

    The biological function of most proteins relies on reversible post-translational modifications, among which phosphorylation is most prominently studied and well recognized. Recently, a growing amount of evidence indicates that acetylation-deacetylation reactions, when applied to crucial mediators, can also robustly affect the function of target proteins and thereby have wide-ranging physiological impacts. Sirtuin 1 (SIRT1), which functions as a nicotinamide adenine dinucleotide (NAD(+))-dependent protein deacetylase, deacetylates a wide variety of metabolic molecules in response to the cellular energy and redox status and as such causes significant changes in metabolic homeostasis. This review surveys the evidence for the emerging role of SIRT1-mediated deacetylation in the control of metabolic homeostasis. PMID:20026274

  6. Adjustments of Protein Metabolism in Fasting Arctic Charr, Salvelinus alpinus

    PubMed Central

    Cassidy, Alicia A.; Saulnier, Roxanne J.; Lamarre, Simon G.

    2016-01-01

    Protein metabolism, including the interrelated processes of synthesis and degradation, mediates the growth of an animal. In ectothermic animals, protein metabolism is responsive to changes in both biotic and abiotic conditions. This study aimed to characterise responses of protein metabolism to food deprivation that occur in the coldwater salmonid, Arctic charr, Salvelinus alpinus. We compared two groups of Arctic charr: one fed continuously and the other deprived of food for 36 days. We measured the fractional rate of protein synthesis (KS) in individuals from the fed and fasted groups using a flooding dose technique modified for the use of deuterium-labelled phenylalanine. The enzyme activities of the three major protein degradation pathways (ubiquitin proteasome, lysosomal cathepsins and the calpain systems) were measured in the same fish. This study is the first to measure both KS and the enzymatic activity of protein degradation in the same fish, allowing us to examine the apparent contribution of different protein degradation pathways to protein turnover in various tissues (red and white muscle, liver, heart and gills). KS was lower in the white muscle and in liver of the fasted fish compared to the fed fish. There were no observable effects of food deprivation on the protease activities in any of the tissues with the exception of liver, where the ubiquitin proteasome pathway seemed to be activated during fasting conditions. Lysosomal proteolysis appears to be the primary degradation pathway for muscle protein, while the ubiquitin proteasome pathway seems to predominate in the liver. We speculate that Arctic charr regulate protein metabolism during food deprivation to conserve proteins. PMID:27096948

  7. Food chain transport of nanoparticles affects behaviour and fat metabolism in fish.

    PubMed

    Cedervall, Tommy; Hansson, Lars-Anders; Lard, Mercy; Frohm, Birgitta; Linse, Sara

    2012-01-01

    Nano-sized (10(-9)-10(-7) m) particles offer many technical and biomedical advances over the bulk material. The use of nanoparticles in cosmetics, detergents, food and other commercial products is rapidly increasing despite little knowledge of their effect on organism metabolism. We show here that commercially manufactured polystyrene nanoparticles, transported through an aquatic food chain from algae, through zooplankton to fish, affect lipid metabolism and behaviour of the top consumer. At least three independent metabolic parameters differed between control and test fish: the weight loss, the triglycerides∶cholesterol ratio in blood serum, and the distribution of cholesterol between muscle and liver. Moreover, we demonstrate that nanoparticles bind to apolipoprotein A-I in fish serum in-vitro, thereby restraining them from properly utilising their fat reserves if absorbed through ingestion. In addition to the metabolic effects, we show that consumption of nanoparticle-containing zooplankton affects the feeding behaviour of the fish. The time it took the fish to consume 95% of the food presented to them was more than doubled for nanoparticle-exposed compared to control fish. Since many nano-sized products will, through the sewage system, end up in freshwater and marine habitats, our study provides a potential bioassay for testing new nano-sized material before manufacturing. In conclusion, our study shows that from knowledge of the molecular composition of the protein corona around nanoparticles it is possible to make a testable molecular hypothesis and bioassay of the potential biological risks of a defined nanoparticle at the organism and ecosystem level.

  8. Co-evolution of metabolism and protein sequences.

    PubMed

    Schütte, Moritz; Klitgord, Niels; Segrè, Daniel; Ebenhöh, Oliver

    2010-01-01

    The set of chemicals producible and usable by metabolic pathways must have evolved in parallel with the enzymes that catalyze them. One implication of this common historical path should be a correspondence between the innovation steps that gradually added new metabolic reactions to the biosphere-level biochemical toolkit, and the gradual sequence changes that must have slowly shaped the corresponding enzyme structures. However, global signatures of a long-term co-evolution have not been identified. Here we search for such signatures by computing correlations between inter-reaction distances on a metabolic network, and sequence distances of the corresponding enzyme proteins. We perform our calculations using the set of all known metabolic reactions, available from the KEGG database. Reaction-reaction distance on the metabolic network is computed as the length of the shortest path on a projection of the metabolic network, in which nodes are reactions and edges indicate whether two reactions share a common metabolite, after removal of cofactors. Estimating the distance between enzyme sequences in a meaningful way requires some special care: for each enzyme commission (EC) number, we select from KEGG a consensus set of protein sequences using the cluster of orthologous groups of proteins (COG) database. We define the evolutionary distance between protein sequences as an asymmetric transition probability between two enzymes, derived from the corresponding pair-wise BLAST scores. By comparing the distances between sequences to the minimal distances on the metabolic reaction graph, we find a small but statistically significant correlation between the two measures. This suggests that the evolutionary walk in enzyme sequence space has locally mirrored, to some extent, the gradual expansion of metabolism. PMID:20238426

  9. Green Tea minimally affects Biomarkers of Inflammation in Obese Subjects with Metabolic Syndrome

    PubMed Central

    Basu, Arpita; Du, Mei; Sanchez, Karah; Leyva, Misti J.; Betts, Nancy M.; Blevins, Steve; Wu, Mingyuan; Aston, Christopher E.; Lyons, Timothy J.

    2010-01-01

    Objective Green tea (Camellia sinensis) has shown to exert cardio-protective benefits in observational studies. The objective of this clinical trial was to assess the effects of green tea on features of metabolic syndrome and inflammation in obese subjects. Methods We conducted a randomized controlled trial in obese subjects with metabolic syndrome. Thirty-five subjects [age (mean±SE) 42.5±1.7 years, BMI 36.1±1.3 kg/m2] completed the 8-week study and were randomly assigned to receive green tea (4 cups/day), green tea extract (2 capsules and 4 cups water/day), or no treatment (4 cups water/day). Both the beverage and extract groups had similar dosing of epigallocatechin-3-gallate (EGCG), the active green tea polyphenol. Fasting blood samples were collected at screening, four, and eight weeks of the study. Results Green tea beverage or extract supplementation did not significantly alter features of metabolic syndrome or biomarkers of inflammation including adiponectin, C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-1β (IL-1β), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1), leptin, or leptin:adiponectin ratio. However, both green tea beverage and extracts significantly reduced plasma serum amyloid alpha (SAA) versus no treatment (p<0.005). Conclusion This study suggests that the daily consumption of green tea beverage or extracts for 8 weeks was well tolerated but did not affect the features of metabolic syndrome. However, green tea significantly reduced plasma SAA, an independent CVD risk factor, in obese subjects with metabolic syndrome. PMID:20605696

  10. Modulation of Glycosaminoglycans Affects PrPSc Metabolism but Does Not Block PrPSc Uptake

    PubMed Central

    Wolf, Hanna; Graßmann, Andrea; Bester, Romina; Hossinger, André; Möhl, Christoph; Paulsen, Lydia; Groschup, Martin H.; Schätzl, Hermann

    2015-01-01

    ABSTRACT Mammalian prions are unconventional infectious agents composed primarily of the misfolded aggregated host prion protein PrP, termed PrPSc. Prions propagate by the recruitment and conformational conversion of cellular prion protein into abnormal prion aggregates on the cell surface or along the endocytic pathway. Cellular glycosaminoglycans have been implicated as the first attachment sites for prions and cofactors for cellular prion replication. Glycosaminoglycan mimetics and obstruction of glycosaminoglycan sulfation affect prion replication, but the inhibitory effects on different strains and different stages of the cell infection have not been thoroughly addressed. We examined the effects of a glycosaminoglycan mimetic and undersulfation on cellular prion protein metabolism, prion uptake, and the establishment of productive infections in L929 cells by two mouse-adapted prion strains. Surprisingly, both treatments reduced endogenous sulfated glycosaminoglycans but had divergent effects on cellular PrP levels. Chemical or genetic manipulation of glycosaminoglycans did not prevent PrPSc uptake, arguing against their roles as essential prion attachment sites. However, both treatments effectively antagonized de novo prion infection independently of the prion strain and reduced PrPSc formation in chronically infected cells. Our results demonstrate that sulfated glycosaminoglycans are dispensable for prion internalization but play a pivotal role in persistently maintained PrPSc formation independent of the prion strain. IMPORTANCE Recently, glycosaminoglycans (GAGs) became the focus of neurodegenerative disease research as general attachment sites for cell invasion by pathogenic protein aggregates. GAGs influence amyloid formation in vitro. GAGs are also found in intra- and extracellular amyloid deposits. In light of the essential role GAGs play in proteinopathies, understanding the effects of GAGs on protein aggregation and aggregate dissemination is crucial

  11. Prenatal hyperandrogenism induces alterations that affect liver lipid metabolism.

    PubMed

    Abruzzese, Giselle Adriana; Heber, Maria Florencia; Ferreira, Silvana Rocio; Velez, Leandro Martin; Reynoso, Roxana; Pignataro, Omar Pedro; Motta, Alicia Beatriz

    2016-07-01

    Prenatal hyperandrogenism is hypothesized as one of the main factors contributing to the development of polycystic ovary syndrome (PCOS). PCOS patients have high risk of developing fatty liver and steatosis. This study aimed to evaluate the role of prenatal hyperandrogenism in liver lipid metabolism and fatty liver development. Pregnant rats were hyperandrogenized with testosterone. At pubertal age, the prenatally hyperandrogenized (PH) female offspring displayed both ovulatory (PHov) and anovulatory (PHanov) phenotypes that mimic human PCOS features. We evaluated hepatic transferases, liver lipid content, the balance between lipogenesis and fatty acid oxidation pathway, oxidant/antioxidant balance and proinflammatory status. We also evaluated the general metabolic status through growth rate curve, basal glucose and insulin levels, glucose tolerance test, HOMA-IR index and serum lipid profile. Although neither PH group showed signs of liver lipid content, the lipogenesis and fatty oxidation pathways were altered. The PH groups also showed impaired oxidant/antioxidant balance, a decrease in the proinflammatory pathway (measured by prostaglandin E2 and cyclooxygenase-2 levels), decreased glucose tolerance, imbalance of circulating lipids and increased risk of metabolic syndrome. We conclude that prenatal hyperandrogenism generates both PHov and PHanov phenotypes with signs of liver alterations, imbalance in lipid metabolism and increased risk of developing metabolic syndrome. The anovulatory phenotype showed more alterations in liver lipogenesis and a more impaired balance of insulin and glucose metabolism, being more susceptible to the development of steatosis.

  12. How does metabolism affect cell death in cancer?

    PubMed

    Villa, Elodie; Ricci, Jean-Ehrland

    2016-07-01

    In cancer research, identifying a specificity of tumor cells compared with 'normal' proliferating cells for targeted therapy is often considered the Holy Grail for researchers and clinicians. Although diverse in origin, most cancer cells share characteristics including the ability to escape cell death mechanisms and the utilization of different methods of energy production. In the current paradigm, aerobic glycolysis is considered the central metabolic characteristic of cancer cells (Warburg effect). However, recent data indicate that cancer cells also show significant changes in other metabolic pathways. Indeed, it was recently suggested that Kreb's cycle, pentose phosphate pathway intermediates, and essential and nonessential amino acids have key roles. Renewed interest in the fact that cancer cells have to reprogram their metabolism in order to proliferate or resist treatment must take into consideration the ability of tumor cells to adapt their metabolism to the local microenvironment (low oxygen, low nutrients). This variety of metabolic sources might be either a strength, resulting in infinite possibilities for adaptation and increased ability to resist chemotherapy-induced death, or a weakness that could be targeted to kill cancer cells. Here, we discuss recent insights showing how energetic metabolism may regulate cell death and how this might be relevant for cancer treatment.

  13. Potato Snakin-1 Gene Silencing Affects Cell Division, Primary Metabolism, and Cell Wall Composition1[W

    PubMed Central

    Nahirñak, Vanesa; Almasia, Natalia Inés; Fernandez, Paula Virginia; Hopp, Horacio Esteban; Estevez, José Manuel; Carrari, Fernando; Vazquez-Rovere, Cecilia

    2012-01-01

    Snakin-1 (SN1) is an antimicrobial cysteine-rich peptide isolated from potato (Solanum tuberosum) that was classified as a member of the Snakin/Gibberellic Acid Stimulated in Arabidopsis protein family. In this work, a transgenic approach was used to study the role of SN1 in planta. Even when overexpressing SN1, potato lines did not show remarkable morphological differences from the wild type; SN1 silencing resulted in reduced height, which was accompanied by an overall reduction in leaf size and severe alterations of leaf shape. Analysis of the adaxial epidermis of mature leaves revealed that silenced lines had 70% to 90% increases in mean cell size with respect to wild-type leaves. Consequently, the number of epidermal cells was significantly reduced in these lines. Confocal microscopy analysis after agroinfiltration of Nicotiana benthamiana leaves showed that SN1-green fluorescent protein fusion protein was localized in plasma membrane, and bimolecular fluorescence complementation assays revealed that SN1 self-interacted in vivo. We further focused our study on leaf metabolism by applying a combination of gas chromatography coupled to mass spectrometry, Fourier transform infrared spectroscopy, and spectrophotometric techniques. These targeted analyses allowed a detailed examination of the changes occurring in 46 intermediate compounds from primary metabolic pathways and in seven cell wall constituents. We demonstrated that SN1 silencing affects cell division, leaf primary metabolism, and cell wall composition in potato plants, suggesting that SN1 has additional roles in growth and development beyond its previously assigned role in plant defense. PMID:22080603

  14. Genetic Alterations Affecting Cholesterol Metabolism and Human Fertility1

    PubMed Central

    DeAngelis, Anthony M.; Roy-O'Reilly, Meaghan; Rodriguez, Annabelle

    2014-01-01

    ABSTRACT Single nucleotide polymorphisms (SNPs) represent genetic variations among individuals in a population. In medicine, these small variations in the DNA sequence may significantly impact an individual's response to certain drugs or influence the risk of developing certain diseases. In the field of reproductive medicine, a significant amount of research has been devoted to identifying polymorphisms which may impact steroidogenesis and fertility. This review discusses current understanding of the effects of genetic variations in cholesterol metabolic pathways on human fertility that bridge novel linkages between cholesterol metabolism and reproductive health. For example, the role of the low-density lipoprotein receptor (LDLR) in cellular metabolism and human reproduction has been well studied, whereas there is now an emerging body of research on the role of the high-density lipoprotein (HDL) receptor scavenger receptor class B type I (SR-BI) in human lipid metabolism and female reproduction. Identifying and understanding how polymorphisms in the SCARB1 gene or other genes related to lipid metabolism impact human physiology is essential and will play a major role in the development of personalized medicine for improved diagnosis and treatment of infertility. PMID:25122065

  15. Root carbon and protein metabolism associated with heat tolerance.

    PubMed

    Huang, Bingru; Rachmilevitch, Shimon; Xu, Jichen

    2012-05-01

    Extensive past efforts have been taken toward understanding heat tolerance mechanisms of the aboveground organs. Root systems play critical roles in whole-plant adaptation to heat stress, but are less studied. This review discusses recent research results revealing some critical physiological and metabolic factors underlying root thermotolerance, with a focus on temperate perennial grass species. Comparative analysis of differential root responses to supraoptimal temperatures by a heat-adapted temperate C3 species, Agrostis scabra, which can survive high soil temperatures up to 45 °C in geothermal areas in Yellow Stone National Park, and a heat-sensitive cogeneric species, Agrostis stolonifera, suggested that efficient carbon and protein metabolism is critical for root thermotolerance. Superior root thermotolerance in a perennial grass was associated with a greater capacity to control respiratory costs through respiratory acclimation, lowering carbon investment in maintenance for protein turnover, and efficiently partitioning carbon into different metabolic pools and alternative respiration pathways. Proteomic analysis demonstrated that root thermotolerance was associated with an increased maintenance of stability and less degradation of proteins, particularly those important for metabolism and energy production. In addition, thermotolerant roots are better able to maintain growth and activity during heat stress by activating stress defence proteins such as those participating in antioxidant defence (i.e. superoxide dismutase, peroxidase, glutathione S-transferase) and chaperoning protection (i.e. heat shock protein).

  16. Root carbon and protein metabolism associated with heat tolerance.

    PubMed

    Huang, Bingru; Rachmilevitch, Shimon; Xu, Jichen

    2012-05-01

    Extensive past efforts have been taken toward understanding heat tolerance mechanisms of the aboveground organs. Root systems play critical roles in whole-plant adaptation to heat stress, but are less studied. This review discusses recent research results revealing some critical physiological and metabolic factors underlying root thermotolerance, with a focus on temperate perennial grass species. Comparative analysis of differential root responses to supraoptimal temperatures by a heat-adapted temperate C3 species, Agrostis scabra, which can survive high soil temperatures up to 45 °C in geothermal areas in Yellow Stone National Park, and a heat-sensitive cogeneric species, Agrostis stolonifera, suggested that efficient carbon and protein metabolism is critical for root thermotolerance. Superior root thermotolerance in a perennial grass was associated with a greater capacity to control respiratory costs through respiratory acclimation, lowering carbon investment in maintenance for protein turnover, and efficiently partitioning carbon into different metabolic pools and alternative respiration pathways. Proteomic analysis demonstrated that root thermotolerance was associated with an increased maintenance of stability and less degradation of proteins, particularly those important for metabolism and energy production. In addition, thermotolerant roots are better able to maintain growth and activity during heat stress by activating stress defence proteins such as those participating in antioxidant defence (i.e. superoxide dismutase, peroxidase, glutathione S-transferase) and chaperoning protection (i.e. heat shock protein). PMID:22328905

  17. Amino Acid Flux from Metabolic Network Benefits Protein Translation: the Role of Resource Availability

    PubMed Central

    Hu, Xiao-Pan; Yang, Yi; Ma, Bin-Guang

    2015-01-01

    Protein translation is a central step in gene expression and affected by many factors such as codon usage bias, mRNA folding energy and tRNA abundance. Despite intensive previous studies, how metabolic amino acid supply correlates with protein translation efficiency remains unknown. In this work, we estimated the amino acid flux from metabolic network for each protein in Escherichia coli and Saccharomyces cerevisiae by using Flux Balance Analysis. Integrated with the mRNA expression level, protein abundance and ribosome profiling data, we provided a detailed description of the role of amino acid supply in protein translation. Our results showed that amino acid supply positively correlates with translation efficiency and ribosome density. Moreover, with the rank-based regression model, we found that metabolic amino acid supply facilitates ribosome utilization. Based on the fact that the ribosome density change of well-amino-acid-supplied genes is smaller than poorly-amino-acid-supply genes under amino acid starvation, we reached the conclusion that amino acid supply may buffer ribosome density change against amino acid starvation and benefit maintaining a relatively stable translation environment. Our work provided new insights into the connection between metabolic amino acid supply and protein translation process by revealing a new regulation strategy that is dependent on resource availability. PMID:26056817

  18. ECHS1 mutations in Leigh disease: a new inborn error of metabolism affecting valine metabolism.

    PubMed

    Peters, Heidi; Buck, Nicole; Wanders, Ronald; Ruiter, Jos; Waterham, Hans; Koster, Janet; Yaplito-Lee, Joy; Ferdinandusse, Sacha; Pitt, James

    2014-11-01

    Two siblings with fatal Leigh disease had increased excretion of S-(2-carboxypropyl)cysteine and several other metabolites that are features of 3-hydroxyisobutyryl-CoA hydrolase (HIBCH) deficiency, a rare defect in the valine catabolic pathway associated with Leigh-like disease. However, this diagnosis was excluded by HIBCH sequencing and normal enzyme activity. In contrast to HIBCH deficiency, the excretion of 3-hydroxyisobutyryl-carnitine was normal in the children, suggesting deficiency of short-chain enoyl-CoA hydratase (ECHS1 gene). This mitochondrial enzyme is active in several metabolic pathways involving fatty acids and amino acids, including valine, and is immediately upstream of HIBCH in the valine pathway. Both children were compound heterozygous for a c.473C > A (p.A158D) missense mutation and a c.414+3G>C splicing mutation in ECHS1. ECHS1 activity was markedly decreased in cultured fibroblasts from both siblings, ECHS1 protein was undetectable by immunoblot analysis and transfection of patient cells with wild-type ECHS1 rescued ECHS1 activity. The highly reactive metabolites methacrylyl-CoA and acryloyl-CoA accumulate in deficiencies of both ECHS1 and HIBCH and are probably responsible for the brain pathology in both disorders. Deficiency of ECHS1 or HIBCH should be considered in children with Leigh disease. Urine metabolite testing can detect and distinguish between these two disorders.

  19. Regulation of intestinal protein metabolism by amino acids.

    PubMed

    Bertrand, Julien; Goichon, Alexis; Déchelotte, Pierre; Coëffier, Moïse

    2013-09-01

    Gut homeostasis plays a major role in health and may be regulated by quantitative and qualitative food intake. In the intestinal mucosa, an intense renewal of proteins occurs, at approximately 50% per day in humans. In some pathophysiological conditions, protein turnover is altered and may contribute to intestinal or systemic diseases. Amino acids are key effectors of gut protein turnover, both as constituents of proteins and as regulatory molecules limiting intestinal injury and maintaining intestinal functions. Many studies have focused on two amino acids: glutamine, known as the preferential substrate of rapidly dividing cells, and arginine, another conditionally essential amino acid. The effects of glutamine and arginine on protein synthesis appear to be model and condition dependent, as are the involved signaling pathways. The regulation of gut protein degradation by amino acids has been minimally documented until now. This review will examine recent data, helping to better understand how amino acids regulate intestinal protein metabolism, and will explore perspectives for future studies.

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

    PubMed

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

    2016-02-01

    Higher protein meals increase satiety and the thermic effect of feeding (TEF) in acute settings, but it is unclear whether these effects remain after a person becomes acclimated to energy restriction or a given protein intake. This study assessed the effects of predominant protein source (omnivorous, beef/pork vs. lacto-ovo vegetarian, soy/legume) and quantity (10%, 20%, or 30% of energy from protein) on appetite, energy expenditure, and cardio-metabolic indices during energy restriction (ER) in overweight and obese adults. Subjects were randomly assigned to one protein source and then consumed diets with different quantities of protein (4 weeks each) in a randomized crossover manner. Perceived appetite ratings (free-living and in-lab), TEF, and fasting cardio-metabolic indices were assessed at the end of each 4-week period. Protein source and quantity did not affect TEF, hunger, or desire to eat, other than a modestly higher daily composite fullness rating with 30% vs. 10% protein diet (p = 0.03). While the 20% and 30% protein diets reduced cholesterol, triacylglycerol, and APO-B vs. 10% protein (p < 0.05), protein source did not affect cardio-metabolic indices. In conclusion, diets varying in protein quantity with either beef/pork or soy/legume as the predominant source have minimal effects on appetite control, energy expenditure and cardio-metabolic risk factors during ER-induced weight loss. PMID:26821042

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

    PubMed Central

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

    2016-01-01

    Higher protein meals increase satiety and the thermic effect of feeding (TEF) in acute settings, but it is unclear whether these effects remain after a person becomes acclimated to energy restriction or a given protein intake. This study assessed the effects of predominant protein source (omnivorous, beef/pork vs. lacto-ovo vegetarian, soy/legume) and quantity (10%, 20%, or 30% of energy from protein) on appetite, energy expenditure, and cardio-metabolic indices during energy restriction (ER) in overweight and obese adults. Subjects were randomly assigned to one protein source and then consumed diets with different quantities of protein (4 weeks each) in a randomized crossover manner. Perceived appetite ratings (free-living and in-lab), TEF, and fasting cardio-metabolic indices were assessed at the end of each 4-week period. Protein source and quantity did not affect TEF, hunger, or desire to eat, other than a modestly higher daily composite fullness rating with 30% vs. 10% protein diet (p = 0.03). While the 20% and 30% protein diets reduced cholesterol, triacylglycerol, and APO-B vs. 10% protein (p < 0.05), protein source did not affect cardio-metabolic indices. In conclusion, diets varying in protein quantity with either beef/pork or soy/legume as the predominant source have minimal effects on appetite control, energy expenditure and cardio-metabolic risk factors during ER-induced weight loss. PMID:26821042

  2. Dietary n-3 PUFA affect lipid metabolism and tissue function-related genes in bovine muscle.

    PubMed

    Hiller, Beate; Hocquette, Jean-Francois; Cassar-Malek, Isabelle; Nuernberg, Gerd; Nuernberg, Karin

    2012-09-01

    Gene expression profiles of bovine longissimus muscle as affected by dietary n-3 v. n-6 fatty acid (FA) intervention were analysed by microarray pre-screening of >3000 muscle biology/meat quality-related genes as well as subsequent quantitative RT-PCR gene expression validation of genes encoding lipogenesis-related transcription factors (CCAAT/enhancer-binding protein β, sterol regulatory element-binding transcription factor 1), key-lipogenic enzymes (acetyl-CoA carboxylase α (ACACA), fatty acid synthase (FASN), stearoyl-CoA desaturase (SCD)), lipid storage-associated proteins (adipose differentiation-related protein (ADFP)) and muscle biology-related proteins (cholinergic receptor, nicotinic, α1, farnesyl diphosphate farnesyl transferase 1, sema domain 3C (SEMA3C)). Down-regulation of ACACA (P = 0·00), FASN (P = 0·09) and SCD (P = 0·02) gene expression upon an n-3 FA intervention directly corresponded to reduced SFA, MUFA and total FA concentrations in longissimus muscle, whereas changes in ADFP (P = 0·00) and SEMA3C (P = 0·05) gene expression indicated improved muscle function via enhanced energy metabolism, vasculogenesis, innervation and mediator synthesis. The present study highlights the significance of dietary n-3 FA intervention on muscle development, maintenance and function, which are relevant for meat quality tailoring of bovine tissues and modulating animal production-relevant physiological processes.

  3. A liver stress-endocrine nexus promotes metabolic integrity during dietary protein dilution.

    PubMed

    Maida, Adriano; Zota, Annika; Sjøberg, Kim A; Schumacher, Jonas; Sijmonsma, Tjeerd P; Pfenninger, Anja; Christensen, Marie M; Gantert, Thomas; Fuhrmeister, Jessica; Rothermel, Ulrike; Schmoll, Dieter; Heikenwälder, Mathias; Iovanna, Juan L; Stemmer, Kerstin; Kiens, Bente; Herzig, Stephan; Rose, Adam J

    2016-09-01

    Dietary protein intake is linked to an increased incidence of type 2 diabetes (T2D). Although dietary protein dilution (DPD) can slow the progression of some aging-related disorders, whether this strategy affects the development and risk for obesity-associated metabolic disease such as T2D is unclear. Here, we determined that DPD in mice and humans increases serum markers of metabolic health. In lean mice, DPD promoted metabolic inefficiency by increasing carbohydrate and fat oxidation. In nutritional and polygenic murine models of obesity, DPD prevented and curtailed the development of impaired glucose homeostasis independently of obesity and food intake. DPD-mediated metabolic inefficiency and improvement of glucose homeostasis were independent of uncoupling protein 1 (UCP1), but required expression of liver-derived fibroblast growth factor 21 (FGF21) in both lean and obese mice. FGF21 expression and secretion as well as the associated metabolic remodeling induced by DPD also required induction of liver-integrated stress response-driven nuclear protein 1 (NUPR1). Insufficiency of select nonessential amino acids (NEAAs) was necessary and adequate for NUPR1 and subsequent FGF21 induction and secretion in hepatocytes in vitro and in vivo. Taken together, these data indicate that DPD promotes improved glucose homeostasis through an NEAA insufficiency-induced liver NUPR1/FGF21 axis. PMID:27548521

  4. Role of Protein–Protein Interactions in Cytochrome P450-Mediated Drug Metabolism and Toxicity

    PubMed Central

    2015-01-01

    Through their unique oxidative chemistry, cytochrome P450 monooxygenases (CYPs) catalyze the elimination of most drugs and toxins from the human body. Protein–protein interactions play a critical role in this process. Historically, the study of CYP–protein interactions has focused on their electron transfer partners and allosteric mediators, cytochrome P450 reductase and cytochrome b5. However, CYPs can bind other proteins that also affect CYP function. Some examples include the progesterone receptor membrane component 1, damage resistance protein 1, human and bovine serum albumin, and intestinal fatty acid binding protein, in addition to other CYP isoforms. Furthermore, disruption of these interactions can lead to altered paths of metabolism and the production of toxic metabolites. In this review, we summarize the available evidence for CYP protein–protein interactions from the literature and offer a discussion of the potential impact of future studies aimed at characterizing noncanonical protein–protein interactions with CYP enzymes. PMID:25133307

  5. 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...

  6. Protein-Tyrosine Phosphatase 1B Substrates and Metabolic Regulation

    PubMed Central

    Bakke, Jesse; Haj, Fawaz G.

    2014-01-01

    Metabolic homeostasis requires integration of complex signaling networks which, when deregulated, contribute to metabolic syndrome and related disorders. Protein-tyrosine phosphatase 1B (PTP1B) has emerged as a key regulator of signaling networks that are implicated in metabolic diseases such as obesity and type 2 diabetes. In this review, we examine mechanisms that regulate PTP1B-substrate interaction, enzymatic activity and experimental approaches to identify PTP1B substrates. We then highlight findings that implicate PTP1B in metabolic regulation. In particular, insulin and leptin signaling are discussed as well as recently identified PTP1B substrates that are involved in endoplasmic reticulum stress response, cell-cell communication, energy balance and vesicle trafficking. In summary, PTP1B exhibits exquisite substrate specificity and is an outstanding pharmaceutical target for obesity and type 2 diabetes. PMID:25263014

  7. 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.

  8. 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. PMID:26306559

  9. Hepatitis C virus core protein impairs metabolic disorder of liver cell via HOTAIR-Sirt1 signalling.

    PubMed

    Li, Zhi-Qin; Gu, Xin-Yu; Hu, Jin-Xing; Ping, Yu; Li, Hua; Yan, Jing-Ya; Li, Juan; Sun, Ran; Yu, Zu-Jing; Zhang, Yi

    2016-07-01

    It has been suggested that Hepatitis C virus (HCV) core protein is associated with metabolic disorders of liver cell. However, the precise mechanism is still unclear. The aim of the present study was to explore the impact of HCV core protein on hepatocyte metabolism by HepG2 and the possible involvement of long non-coding (lnc) RNAs in this process. The effect of HCV core protein on lncRNAs expression was examined with quantitative RT-PCR (qRT-PCR). Manipulation of HVC core protein and lncRNA HOTAIR was to evaluate the role of interaction between them on cell metabolism-related gene expression and cellular metabolism. The potential downstream Sirt1 signal was examined by western blotting and qRT-PCR. Our data suggested that suppression of HOTAIR abrogates HCV core protein-induced reduction in Sirt1 and differential expression of glucose- and lipid-metabolism-related genes. Also it benefits for metabolic homoeostasis of hepatocyte indicated by restoration of cellular reactive oxygen species (ROS) level and NAD/NADH ratio. By manipulation of HOTAIR, we concluded that HOTAIR negatively regulates Sirt1 expression through affecting its promotor methylation. Moreover, overexpression of Sirt1 reverses pcDNA-HOTAIR-induced glucose- and lipid-metabolism-related gene expression. Our study suggests that HCV core protein causes dysfunction of glucose and lipid metabolism in liver cells through HOTAIR-Sirt1 signalling pathway. PMID:27129296

  10. 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

  11. Protein homeostasis disorders of key enzymes of amino acids metabolism: mutation-induced protein kinetic destabilization and new therapeutic strategies.

    PubMed

    Pey, Angel L

    2013-12-01

    Many inborn errors of amino acids metabolism are caused by single point mutations affecting the ability of proteins to fold properly (i.e., protein homeostasis), thus leading to enzyme loss-of-function. Mutations may affect protein homeostasis by altering intrinsic physical properties of the polypeptide (folding thermodynamics, and rates of folding/unfolding/misfolding) as well as the interaction of partially folded states with elements of the protein homeostasis network (such as molecular chaperones and proteolytic machineries). Understanding these mutational effects on protein homeostasis is required to develop new therapeutic strategies aimed to target specific features of the mutant polypeptide. Here, I review recent work in three different diseases of protein homeostasis associated to inborn errors of amino acids metabolism: phenylketonuria, inherited homocystinuria and primary hyperoxaluria type I. These three different genetic disorders involve proteins operating in different cell organelles and displaying different structural complexities. Mutations often decrease protein kinetic stability of the native state (i.e., its half-life for irreversible denaturation), which can be studied using simple kinetic models amenable to biophysical and biochemical characterization. Natural ligands and pharmacological chaperones are shown to stabilize mutant enzymes, thus supporting their therapeutic application to overcome protein kinetic destabilization. The role of molecular chaperones in protein folding and misfolding is also discussed as well as their potential pharmacological modulation as promising new therapeutic approaches. Since current available treatments for these diseases are either burdening or only successful in a fraction of patients, alternative treatments must be considered covering studies from protein structure and biophysics to studies in animal models and patients.

  12. Scoparone affects lipid metabolism in primary hepatocytes using lipidomics

    PubMed Central

    Zhang, Aihua; Qiu, Shi; Sun, Hui; Zhang, Tianlei; Guan, Yu; Han, Ying; Yan, Guangli; Wang, Xijun

    2016-01-01

    Lipidomics, which focuses on the global study of molecular lipids in biological systems, could provide valuable insights about disease mechanisms. In this study, we present a nontargeted lipidomics strategy to determine cellular lipid alterations after scoparone exposure in primary hepatocytes. Lipid metabolic profiles were analyzed by high-performance liquid chromatography coupled with time-of-flight mass spectrometry, and a novel imaging TransOmics tool has been developed for the analysis of high-resolution MS data, including the data pretreatment, visualization, automated identification, deconvolution and quantification of lipid species. Chemometric and statistical analyses of the obtained lipid fingerprints revealed the global lipidomic alterations and tested the therapeutic effects of scoparone. Identification of ten proposed lipids contributed to the better understanding of the effects of scoparone on lipid metabolism in hepatocytes. The most striking finding was that scoparone caused comprehensive lipid changes, as represented by significant changes of the identificated lipids. The levels of identified PG(19:1(9Z)/14:0), PE(17:1(9Z)/0:0), PE(19:1(9Z)/0:0) were found to be upregulated in ethanol-induced group, whereas the levels in scoparone group were downregulated. Lipid metabolism in primary hepatocytes was changed significantly by scoparone treatment. We believe that this novel approach could substantially broaden the applications of high mass resolution mass spectrometry for cellular lipidomics. PMID:27306123

  13. Post-uptake metabolism affects quantification of amino acid uptake.

    PubMed

    Warren, Charles R

    2012-01-01

    • The quantitative significance of amino acids to plant nutrition remains controversial. This experiment determined whether post-uptake metabolism and root to shoot export differ between glycine and glutamine, and examined implications for estimation of amino acid uptake. • Field soil containing a Eucalyptus pauciflora seedling was injected with uniformly (13)C- and (15)N-labelled glycine or glutamine. I quantified (15)N and (13)C excess in leaves and roots and intact labelled amino acids in leaves, roots and stem xylem sap. A tunable diode laser quantified fluxes of (12)CO(2) and (13)CO(2) from leaves and soil. • 60-360 min after addition of amino acid, intact molecules of U-(13)C,(15)N glutamine were < 5% of (15)N excess in roots, whereas U-(13)C,(15)N glycine was 30-100% of (15)N excess in roots. Intact molecules of glutamine, but not glycine, were exported from roots to shoots. • Post-uptake metabolism and transport complicate interpretation of isotope labelling such that root and shoot contents of intact amino acid, (13)C and (15)N may not reflect rates of uptake. Future experiments should focus on reconciling discrepancies between intact amino acid, (13)C and (15)N by determining the turnover of amino acids within roots. Alternatively, post-uptake metabolism and transport could be minimized by harvesting plants within minutes of isotope addition.

  14. Environmental factors affecting indole metabolism under anaerobic conditions.

    PubMed Central

    Madsen, E L; Francis, A J; Bollag, J M

    1988-01-01

    The influence of physiological and environmental factors on the accumulation of oxindole during anaerobic indole metabolism was investigated by high-performance liquid chromatography. Under methanogenic conditions, indole was temporarily converted to oxindole in stoichiometric amounts in media inoculated with three freshwater sediments and an organic soil. In media inoculated with methanogenic sewage sludge, the modest amounts of oxindole detected at 35 degrees C reached higher concentrations and persisted longer when the incubation temperature was decreased from 35 to 15 degrees C. Also, decreasing the concentration of sewage sludge used as an inoculum from 50 to 1% caused an increase in the accumulation of oxindole from 10 to 75% of the indole added. Under denitrifying conditions, regardless of the concentration or source of the inoculum, oxindole appeared in trace amounts but did not accumulate during indole metabolism. In addition, denitrifying consortia which previously metabolized indole degraded oxindole with no lag period. Our data suggest that oxindole accumulation under methanogenic, but not under denitrifying conditions is caused by differences between relative rates of oxindole production and destruction. PMID:3345080

  15. Metabolic engineering of Escherichia coli to improve recombinant protein production.

    PubMed

    Liu, Min; Feng, Xinjun; Ding, Yamei; Zhao, Guang; Liu, Huizhou; Xian, Mo

    2015-12-01

    Escherichia coli is one of the most widely used strains for recombinant protein production. However, obstacles also exist in both academic researches and industrial applications, such as the metabolic burden, the carbon source waste, and the cells' physiological deterioration. This article reviews recent approaches for improving recombinant protein production in metabolic engineering, including workhorse selection, stress factor application, and carbon flux regulation. Selecting a suitable host is the first key point for recombinant protein production. In general, it all depends on characteristics of the strains and the target proteins. It will be triggered cells physiological deterioration when the medium is significantly different from the cell's natural environment. Coexpression of stress factors can help proteins to fold into their native conformation. Carbon flux regulation is a direct approach for redirecting more carbon flux toward the desirable pathways and products. However, some undesirable consequences are usually found in metabolic engineering, such as glucose transport inhibition, cell growth retardation, and useless metabolite accumulation. More efficient regulators and platform cell factories should be explored to meet a variety of production demands.

  16. Culture surfaces coated with various implant materials affect chondrocyte growth and metabolism.

    PubMed

    Hambleton, J; Schwartz, Z; Khare, A; Windeler, S W; Luna, M; Brooks, B P; Dean, D D; Boyan, B D

    1994-07-01

    The effect on chondrocyte metabolism of culture surfaces sputter-coated with various materials used for orthopaedic implants was studied and correlated with the stage of cartilage cell maturation. Confluent, fourth-passage chondrocytes from the costochondral resting zone and growth zone of rats were cultured for 6 or 9 days on 24-well plates sputter-coated with ultrathin films of titanium, titanium dioxide, aluminum oxide, zirconium oxide, and calcium phosphate (1.67:1). Corona-discharged tissue culture plastic served as the control. The effect of surface material was examined with regard to cell morphology; cell proliferation (cell number) and DNA synthesis ([3H]thymidine incorporation); RNA synthesis ([3H]uridine incorporation); collagenase-digestible protein, noncollagenase-digestible protein, and percentage of collagen production; and alkaline phosphatase-specific activity, both in the cell layer and in trypsinized chondrocytes. Cell morphology was dependent on surface material; only cells cultured on titanium had an appearance similar to that of cells cultured on plastic. While titanium or titanium dioxide surfaces had no effect on cell number or [3H]thymidine incorporation, aluminum oxide, calcium phosphate, and zirconium oxide surfaces inhibited both parameters. Cells cultured on aluminum oxide, calcium phosphate, zirconium oxide, and titanium dioxide exhibited decreased collagenase-digestible protein, noncollagenase-digestible protein, and percentage of collagen production, but [3H]uridine incorporation was decreased only in those chondrocytes cultured on aluminum oxide, calcium phosphate, or zirconium oxide. Chondrocytes cultured on titanium had greater alkaline phosphatase-specific activity than did cells cultured on plastic, but the incorporation of [3H]uridine and production of collagenase-digestible protein, noncollagenase-digestible protein, and percentage of collagen was comparable. The response of chondrocytes from the growth zone and resting zone

  17. Protein restriction during pregnancy affects postnatal growth in swine progeny.

    PubMed

    Schoknecht, P A; Pond, W G; Mersmann, H J; Maurer, R R

    1993-11-01

    Protein deficiency during pregnancy affects fetal development. The critical period, when the fetus is most susceptible to maternal protein deficiency and its effect on neonatal growth, is unknown. Therefore, we studied the effect of a protein-restricted diet during early and late pregnancy and throughout pregnancy on growth of pigs from birth to market weight. Sows were fed a control (13% protein) or protein-restricted (0.5% protein) diet throughout pregnancy or protein-restricted diet from d 1 to 44, then control diet to term or control diet from d 1 to 81, then the protein-restricted diet to term. In Experiment 1, birth weights were measured, and 12 pigs/diet group were weaned at 4 wk and raised to market weight. Feeding the protein-restricted diet throughout pregnancy reduced birth and slaughter weights, whereas the control followed by protein-restricted and protein-restricted followed by control diets reduced only birth weight relative to controls. Indices of carcass lean were reduced in the protein-restricted piglets, with carcass fat not affected. In Experiment 2, control and control-protein-restricted litters were reduced to six piglets and 3/litter cross-fostered to a sow of the other treatment group. After weaning at 4 wk, 4 piglets/group were individually fed to 8 wk. The control and control followed by protein-restricted diet fed piglets had similar weights at birth, but piglets raised by a control-protein-restricted sow tended to weight less at weaning than their littermates raised by a control sow. After weaning, these piglets had greater feed intakes relative to other groups and there were no weight differences by 8 wk.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Protein and leucine metabolism in maple syrup urine disease

    SciTech Connect

    Thompson, G.N.; Bresson, J.L.; Pacy, P.J.; Bonnefont, J.P.; Walter, J.H.; Leonard, J.V.; Saudubray, J.M.; Halliday, D. )

    1990-04-01

    Constant infusions of (13C)leucine and (2H5)phenylalanine were used to trace leucine and protein kinetics, respectively, in seven children with maple syrup urine disease (MSUD) and eleven controls matched for age and dietary protein intake. Despite significant elevations of plasma leucine (mean 351 mumol/l, range 224-477) in MSUD subjects, mean whole body protein synthesis (3.78 +/- 0.42 (SD) g.kg-1. 24 h-1) and catabolism (4.07 +/- 0.46) were similar to control values (3.69 +/- 0.50 and 4.09 +/- 0.50, respectively). The relationship between phenylalanine and leucine fluxes was also similar in MSUD subjects (mean phenylalanine-leucine flux ratio 0.35 +/- 0.07) and previously reported adult controls (0.33 +/- 0.02). Leucine oxidation was undetectable in four of the MSUD subjects and very low in the other three (less than 4 mumol.kg-1.h-1; controls 13-20). These results show that persistent elevation in leucine concentration has no effect on protein synthesis. The marked disturbance in leucine metabolism in MSUD did not alter the relationship between rates of catabolism of protein to phenylalanine and leucine, which provides further support for the validity of the use of a single amino acid to trace whole body protein metabolism. The minimal leucine oxidation in MSUD differs from findings in other inborn metabolic errors and indicates that in patients with classical MSUD there is no significant route of leucine disposal other than through protein synthesis.

  19. In Ovo Injection of Betaine Affects Hepatic Cholesterol Metabolism through Epigenetic Gene Regulation in Newly Hatched Chicks

    PubMed Central

    Hu, Yun; Sun, Qinwei; Li, Xiaoliang; Wang, Min; Cai, Demin; Li, Xi; Zhao, Ruqian

    2015-01-01

    Betaine is reported to regulate hepatic cholesterol metabolism in mammals. Chicken eggs contain considerable amount of betaine, yet it remains unknown whether and how betaine in the egg affects hepatic cholesterol metabolism in chicks. In this study, eggs were injected with betaine at 2.5 mg/egg and the hepatic cholesterol metabolism was investigated in newly hatched chicks. Betaine did not affect body weight or liver weight, but significantly increased the serum concentration (P < 0.05) and the hepatic content (P < 0.01) of cholesterol. Accordingly, the cholesterol biosynthetic enzyme HMGCR was up-regulated (P < 0.05 for both mRNA and protein), while CYP7A1 which converts cholesterol to bile acids was down-regulated (P < 0.05 for mRNA and P = 0.07 for protein). Moreover, hepatic protein content of the sterol-regulatory element binding protein 1 which regulates cholesterol and lipid biosynthesis, and the mRNA abundance of ATP binding cassette sub-family A member 1 (ABCA1) which mediates cholesterol counter transport were significantly (P < 0.05) increased in betaine-treated chicks. Meanwhile, hepatic protein contents of DNA methyltransferases 1 and adenosylhomocysteinase-like 1 were increased (P < 0.05), which was associated with global genomic DNA hypermethylation (P < 0.05) and diminished gene repression mark histone H3 lysine 27 trimethylation (P < 0.05). Furthermore, CpG methylation level on gene promoters was found to be increased (P < 0.05) for CYP7A1 yet decreased (P < 0.05) for ABCA1. These results indicate that in ovo betaine injection regulates hepatic cholesterol metabolism in chicks through epigenetic mechanisms including DNA and histone methylations. PMID:25860502

  20. In Ovo injection of betaine affects hepatic cholesterol metabolism through epigenetic gene regulation in newly hatched chicks.

    PubMed

    Hu, Yun; Sun, Qinwei; Li, Xiaoliang; Wang, Min; Cai, Demin; Li, Xi; Zhao, Ruqian

    2015-01-01

    Betaine is reported to regulate hepatic cholesterol metabolism in mammals. Chicken eggs contain considerable amount of betaine, yet it remains unknown whether and how betaine in the egg affects hepatic cholesterol metabolism in chicks. In this study, eggs were injected with betaine at 2.5 mg/egg and the hepatic cholesterol metabolism was investigated in newly hatched chicks. Betaine did not affect body weight or liver weight, but significantly increased the serum concentration (P < 0.05) and the hepatic content (P < 0.01) of cholesterol. Accordingly, the cholesterol biosynthetic enzyme HMGCR was up-regulated (P < 0.05 for both mRNA and protein), while CYP7A1 which converts cholesterol to bile acids was down-regulated (P < 0.05 for mRNA and P = 0.07 for protein). Moreover, hepatic protein content of the sterol-regulatory element binding protein 1 which regulates cholesterol and lipid biosynthesis, and the mRNA abundance of ATP binding cassette sub-family A member 1 (ABCA1) which mediates cholesterol counter transport were significantly (P < 0.05) increased in betaine-treated chicks. Meanwhile, hepatic protein contents of DNA methyltransferases 1 and adenosylhomocysteinase-like 1 were increased (P < 0.05), which was associated with global genomic DNA hypermethylation (P < 0.05) and diminished gene repression mark histone H3 lysine 27 trimethylation (P < 0.05). Furthermore, CpG methylation level on gene promoters was found to be increased (P < 0.05) for CYP7A1 yet decreased (P < 0.05) for ABCA1. These results indicate that in ovo betaine injection regulates hepatic cholesterol metabolism in chicks through epigenetic mechanisms including DNA and histone methylations.

  1. Factors affecting antipyrine metabolism in West African villagers.

    PubMed

    Fraser, H S; Bulpitt, C J; Kahn, C; Mould, G; Mucklow, J C; Dollery, C T

    1976-09-01

    Saliva half-life of antipyrine was studied in 49 healthy Gambians between 20 and 60 yr of age of whom 27 were male (mean age, 44.5) and 22 female (mean age, 39.1). Body wieght, height, ponderal index, albumin, and hemoglobin were moderately reduced compared to accepted normal values. Antipyrine half-life was 13.6 +/- 0.58 (SEM) hr. Multiple regression analysis showed that sex, cola nut consumption, hemoglobin in women, and height in men were statiscally significant independent predictors of antipyrine half-life. Half-life was shorter in women, decreased with an increase in height in men, and was prolonged by cola nut consumption. Half-life in women increased with hemoglobin. These factors explained 36% of the variation and suggest that geographic differences in the environment could be important in drug metabolism in man. PMID:954356

  2. 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.

  3. 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,...

  4. Expression data on liver metabolic pathway genes and proteins

    PubMed Central

    Raja Gopal Reddy, Mooli; Pavan Kumar, Chodisetti; Mahesh, Malleswarapu; Sravan Kumar, Manchiryala; Jeyakumar, Shanmugam M.

    2016-01-01

    Here, we present the expression data on various metabolic pathways of liver with special emphasize on lipid and carbohydrate metabolism and long chain polyunsaturated fatty acid (PUFA) synthesis, both at gene and protein levels. The data were obtained to understand the effect of vitamin A deficiency on the expression status (both gene and protein levels) of some of the key factors involved in lipogenesis, fatty acid oxidation, triglyceride secretion, long chain PUFA, resolvin D1 synthesis, glucose transport and glycogen synthesis of liver, using modern biology tools, such as quantitative real-time PCR (RT-PCR) and immunoblotting techniques. This data article provides the supporting evidence to the article “Vitamin A deficiency suppresses high fructose-induced triglyceride synthesis and elevates resolvin D1 levels” [1] and therefore, these data may be referred back, for comprehensive understanding and interpretations and for future studies. PMID:26909377

  5. The Involvement of Transport Proteins in Transcriptional and Metabolic Regulation

    PubMed Central

    Västermark, Åke; Saier, Milton H.

    2014-01-01

    Transport proteins have sometimes gained secondary regulatory functions that influence gene expression and metabolism. These functions allow communication with the external world via mechanistically distinctive signal transduction pathways. In this brief review we focus on three transport systems in Escherichia coli that control and coordinate carbon, exogenous hexose-phosphate and phosphorous metabolism. The transport proteins that play central roles in these processes are (1) the phosphoenolpyruvate (PEP)-dependent phosphotransferase system, PTS, (2) the glucose-6-phosphate receptor, UhpC, and (3) the phosphate-specific transporter, PstSABC, respectively. While the PTS participates in multiple complex regulatory processes, three of which are discussed here, UhpC and the Pst transporters exemplify differing strategies. PMID:24513656

  6. AMP-activated protein kinase and metabolic control

    PubMed Central

    Viollet, Benoit; Andreelli, Fabrizio

    2011-01-01

    AMP-activated protein kinase (AMPK), a phylogenetically conserved serine/threonine protein kinase, is a major regulator of cellular and whole-body energy homeostasis that coordinates metabolic pathways in order to balance nutrient supply with energy demand. It is now recognized that pharmacological activation of AMPK improves blood glucose homeostasis, lipid profile and blood pressure in insulin-resistant rodents. Indeed, AMPK activation mimics the beneficial effects of physical activity or those of calorie restriction by acting on multiple cellular targets. In addition it is now demonstrated that AMPK is one of the probable (albeit indirect) targets of major antidiabetic drugs including, the biguanides (metformin) and thiazolidinediones, as well as of insulin sensitizing adipokines (e.g., adiponectin). Taken together, such findings highlight the logic underlying the concept of targeting the AMPK pathway for the treatment of metabolic syndrome and type 2 diabetes. PMID:21484577

  7. Decreased Zinc Availability Affects Glutathione Metabolism in Neuronal Cells and in the Developing Brain

    PubMed Central

    Omata, Yo; Salvador, Gabriela A.; Oteiza, Patricia I.

    2013-01-01

    A deficit in zinc (Zn) availability can increase cell oxidant production, affect the antioxidant defense system, and trigger oxidant-sensitive signals in neuronal cells. This work tested the hypothesis that a decreased Zn availability can affect glutathione (GSH) metabolism in the developing rat brain and in neuronal cells in culture, as well as the capacity of human neuroblastoma IMR-32 cells to upregulate GSH when challenged with dopamine (DA). GSH levels were low in the brain of gestation day 19 (GD19) fetuses from dams fed marginal Zn diets throughout gestation and in Zn-deficient IMR-32 cells. γ-Glutamylcysteine synthetase (GCL), the first enzyme in the GSH synthetic pathway, was altered by Zn deficiency (ZD). The protein and mRNA levels of the GCL modifier (GCLM) and catalytic (GCLC) subunits were lower in the Zn-deficient GD19 fetal brain and in IMR-32 cells compared with controls. The nuclear translocation of transcription factor nuclear factor (erythroid-derived 2)-like 2, which controls GCL transcription, was impaired by ZD. Posttranslationally, the caspase-3-dependent GCLC cleavage was high in Zn-deficient IMR-32 cells. Cells challenged with DA showed an increase in GCLM and GCLC protein and mRNA levels and a consequent increase in GSH concentration. Although Zn-deficient cells partially upregulated GCL subunits after exposure to DA, GSH content remained low. In summary, results show that a low Zn availability affects the GSH synthetic pathway in neuronal cells and fetal brain both at transcriptional and posttranslational levels. This can in part underlie the GSH depletion associated with ZD and the high sensitivity of Zn-deficient neurons to pro-oxidative stressors. PMID:23377617

  8. Altered cobalamin metabolism in Escherichia coli btuR mutants affects btuB gene regulation.

    PubMed Central

    Lundrigan, M D; Kadner, R J

    1989-01-01

    Synthesis of the Escherichia coli outer membrane protein BtuB, which mediates the binding and transport of vitamin B12, is repressed when cells are grown in the presence of vitamin B12. Expression of btuB-lacZ fusions was also found to be repressed, and selection for constitutive production of beta-galactosidase in the presence of vitamin B12 yielded mutations at btuR. The btuR locus, at 27.9 min on the chromosome map, was isolated on a 952-base-pair EcoRV fragment, and its nucleotide sequence was determined. The BtuR protein was identified in maxicells as a 22,000-dalton polypeptide, as predicted from the nucleotide sequence. Strains mutant at btuR had negligible pools of adenosylcobalamin but did convert vitamin B12 into other derivatives. Although btuB expression in a btuR strain could not be repressed by cyano- or methylcobalamin, it was repressed by adenosylcobalamin. Growth on ethanolamine as the sole nitrogen source requires adenosylcobalamin. btuR mutants grew on ethanolamine but were affected in the length of the lag period before initiation of growth, which suggested that an alternative route for adenosylcobalamin synthesis might exist. No mutations were found that conferred constitutive btuB expression in the presence of adenosylcobalamin. Other genes near btuR may also be involved in cobalamin metabolism, as suggested from the complementation behavior of strains generated by excision of the Tn10 element in btuR. These results indicated that the btuR product is involved in the metabolism of adenosylcobalamin and that this cofactor, or some derivative, controls btuB expression. Images PMID:2644187

  9. Ozone treatment affects pigment precursor metabolism in pine seedlings.

    PubMed

    Shamay, Y.; Raskin, V. I.; Brandis, A. S.; Steinberger, H. E.; Marder, J. B.; Schwartz, A.

    2001-06-01

    Five-week-old seedlings of Pinus halepensis Mill. and Pinus brutia Ten. were exposed to air polluted with ozone (O3) (250 nl l-1, 12 h day-1 for 4 days) or to ambient air containing ca 10-20 nl l-1 O3, in the light (180 &mgr;mol m-2 s-1 photosynthetic photon flux density [PPFD], 12 h day-1) and then fed for 24 h in the light (100 &mgr;mol m-2 s-1 PPFD) with various radioactive precursors of chlorophyll (Chl) and carotene biosynthesis: 5-[4-14C]-aminolevulinic acid (14C-ALA), L-[14C(U)]-glutamic acid (14C-Glu), or D,L-[2-14C]-mevalonic acid (14C-MVA). Pigments were then extracted from cotyledons and fully expanded needles. Chl a and carotene were separated by thin-layer chromatography and high-performance liquid chromatography and their specific activities were determined. 14C-ALA and 14C-Glu labels were incorporated into Chl a and carotene. Exposure to O3 did not inhibit incorporation of 14C-ALA into Chl a molecules, but hydrolysis of Chl a showed that O3 inhibited phytol labelling of Chl a. Labelling of carotene was also inhibited by O3, but not when 14C-MVA was used as the label. These data suggest that O3 treatment inhibits (directly or indirectly) the biosynthesis of isoprenoids from products of ALA and Glu metabolism in the plastid, but not from MVA in the cytosol. This inhibition was more prominent when 14C-ALA was used as the label than when 14C-Glu was the labelling precursor. A significant increase in pheophorbide a, a tetrapyrrole component of Chl a labelling, and a concomitant decrease in phytol labelling was observed following incubation of O3-treated pine seedlings with 14C-ALA and 14C-Glu. Stronger inhibition of carotene biosynthesis and activation of Chl a tetrapyrrole labelling by 14C-ALA (in comparison with 14C-Glu) indicated that exposure to O3 inhibits the conversion of ALA to Glu as the first step in ALA catabolism. These results also suggested a more intensive Glu metabolism (in comparison with ALA) for carotene biosynthesis in the cytosol, as

  10. Ozone treatment affects pigment precursor metabolism in pine seedlings.

    PubMed

    Shamay, Y.; Raskin, V. I.; Brandis, A. S.; Steinberger, H. E.; Marder, J. B.; Schwartz, A.

    2001-06-01

    Five-week-old seedlings of Pinus halepensis Mill. and Pinus brutia Ten. were exposed to air polluted with ozone (O3) (250 nl l-1, 12 h day-1 for 4 days) or to ambient air containing ca 10-20 nl l-1 O3, in the light (180 &mgr;mol m-2 s-1 photosynthetic photon flux density [PPFD], 12 h day-1) and then fed for 24 h in the light (100 &mgr;mol m-2 s-1 PPFD) with various radioactive precursors of chlorophyll (Chl) and carotene biosynthesis: 5-[4-14C]-aminolevulinic acid (14C-ALA), L-[14C(U)]-glutamic acid (14C-Glu), or D,L-[2-14C]-mevalonic acid (14C-MVA). Pigments were then extracted from cotyledons and fully expanded needles. Chl a and carotene were separated by thin-layer chromatography and high-performance liquid chromatography and their specific activities were determined. 14C-ALA and 14C-Glu labels were incorporated into Chl a and carotene. Exposure to O3 did not inhibit incorporation of 14C-ALA into Chl a molecules, but hydrolysis of Chl a showed that O3 inhibited phytol labelling of Chl a. Labelling of carotene was also inhibited by O3, but not when 14C-MVA was used as the label. These data suggest that O3 treatment inhibits (directly or indirectly) the biosynthesis of isoprenoids from products of ALA and Glu metabolism in the plastid, but not from MVA in the cytosol. This inhibition was more prominent when 14C-ALA was used as the label than when 14C-Glu was the labelling precursor. A significant increase in pheophorbide a, a tetrapyrrole component of Chl a labelling, and a concomitant decrease in phytol labelling was observed following incubation of O3-treated pine seedlings with 14C-ALA and 14C-Glu. Stronger inhibition of carotene biosynthesis and activation of Chl a tetrapyrrole labelling by 14C-ALA (in comparison with 14C-Glu) indicated that exposure to O3 inhibits the conversion of ALA to Glu as the first step in ALA catabolism. These results also suggested a more intensive Glu metabolism (in comparison with ALA) for carotene biosynthesis in the cytosol, as

  11. Metabolic impact assessment for heterologous protein production in Streptomyces lividans based on genome-scale metabolic network modeling.

    PubMed

    Lule, Ivan; D'Huys, Pieter-Jan; Van Mellaert, Lieve; Anné, Jozef; Bernaerts, Kristel; Van Impe, Jan

    2013-11-01

    The metabolic impact exerted on a microorganism due to heterologous protein production is still poorly understood in Streptomyces lividans. In this present paper, based on exometabolomic data, a proposed genome-scale metabolic network model is used to assess this metabolic impact in S. lividans. Constraint-based modeling results obtained in this work revealed that the metabolic impact due to heterologous protein production is widely distributed in the genome of S. lividans, causing both slow substrate assimilation and a shift in active pathways. Exchange fluxes that are critical for model performance have been identified for metabolites of mouse tumor necrosis factor, histidine, valine and lysine, as well as biomass. Our results unravel the interaction of heterologous protein production with intracellular metabolism of S. lividans, thus, a possible basis for further studies in relieving the metabolic burden via metabolic or bioprocess engineering.

  12. [How strongly does heavy work in the heat affect metabolism?].

    PubMed

    Zöller, H; May, B; Weiss, M; Gross, W

    1981-06-19

    The study covered 39 acclimatised workers of a ball-bearing forge, aged 39,03 +/- 9,95 years. Temperature of the air, relative humidity and air speed were measured immediately at work. Additionally electrocardiogram, heart rate and temperature of the skin were continuously transmitted by telemetry. Before and at the end of the shift analysis of blood pressure, heart rate, electrocardiogram, blood cells and coagulation, serum acidity and a great number of other metabolic parameters was performed. The netto calories were calculated as 3250 kcal/8 hours (= 13585 kJ/8 hours). Hematological analysis demonstrated a tendency to increase of leucocytes favouring neutrophil granulocytes. The main alterations comprised decrease of actual pH, base excess and standard bicarbonate. Furthermore serum lactate and triglycerides increased, creatinine attained the upper limit of the normal range, mineralogram remained unchanged by drinking ad libitum. The so called "liver enzymes" remained stable. As to circulatory parameters systolic blood pressure slightly declined whilst heart rate increased.

  13. Model based engineering of Pichia pastoris central metabolism enhances recombinant protein production

    PubMed Central

    Nocon, Justyna; Steiger, Matthias G.; Pfeffer, Martin; Sohn, Seung Bum; Kim, Tae Yong; Maurer, Michael; Rußmayer, Hannes; Pflügl, Stefan; Ask, Magnus; Haberhauer-Troyer, Christina; Ortmayr, Karin; Hann, Stephan; Koellensperger, Gunda; Gasser, Brigitte; Lee, Sang Yup; Mattanovich, Diethard

    2014-01-01

    The production of recombinant proteins is frequently enhanced at the levels of transcription, codon usage, protein folding and secretion. Overproduction of heterologous proteins, however, also directly affects the primary metabolism of the producing cells. By incorporation of the production of a heterologous protein into a genome scale metabolic model of the yeast Pichia pastoris, the effects of overproduction were simulated and gene targets for deletion or overexpression for enhanced productivity were predicted. Overexpression targets were localized in the pentose phosphate pathway and the TCA cycle, while knockout targets were found in several branch points of glycolysis. Five out of 9 tested targets led to an enhanced production of cytosolic human superoxide dismutase (hSOD). Expression of bacterial β-glucuronidase could be enhanced as well by most of the same genetic modifications. Beneficial mutations were mainly related to reduction of the NADP/H pool and the deletion of fermentative pathways. Overexpression of the hSOD gene itself had a strong impact on intracellular fluxes, most of which changed in the same direction as predicted by the model. In vivo fluxes changed in the same direction as predicted to improve hSOD production. Genome scale metabolic modeling is shown to predict overexpression and deletion mutants which enhance recombinant protein production with high accuracy. PMID:24853352

  14. Maternal age affects brain metabolism in adult children of mothers affected by Alzheimer’s disease

    PubMed Central

    Mosconi, Lisa; Tsui, Wai; Murray, John; McHugh, Pauline; Li, Yi; Williams, Schantel; Pirraglia, Elizabeth; Glodzik, Lidia; De Santi, Susan; Vallabhajosula, Shankar; de Leon, Mony J.

    2011-01-01

    Cognitively normal (NL) individuals with a maternal history of late-onset Alzheimer’s disease (MH) show reduced brain glucose metabolism on FDG-PET as compared to those with a paternal history (PH) and those with negative family history (NH) of Alzheimer’s disease (AD). This FDG-PET study investigates whether metabolic deficits in NL MH are associated with advancing maternal age at birth. Ninety-six NL individuals with FDG-PET were examined, including 36 MH, 24 PH, and 36 NH. Regional-to-whole brain gray matter standardized FDG uptake value ratios were examined for associations with parental age across groups using automated regions-of-interest and statistical parametric mapping. Groups were comparable for clinical and neuropsychological measures. Brain metabolism in AD-vulnerable regions was lower in MH compared to NH and PH, and negatively correlated with maternal age at birth only in MH. There were no associations between paternal age and metabolism in any group. Evidence for a maternally inherited, maternal age-related mechanism provides further insight on risk factors and genetic transmission in late-onset AD. PMID:21514691

  15. Maternal age affects brain metabolism in adult children of mothers affected by Alzheimer's disease.

    PubMed

    Mosconi, Lisa; Tsui, Wai; Murray, John; McHugh, Pauline; Li, Yi; Williams, Schantel; Pirraglia, Elizabeth; Glodzik, Lidia; De Santi, Susan; Vallabhajosula, Shankar; de Leon, Mony J

    2012-03-01

    Cognitively normal (NL) individuals with a maternal history of late-onset Alzheimer's disease (MH) show reduced brain glucose metabolism on FDG-PET as compared to those with a paternal history (PH) and those with negative family history (NH) of Alzheimer's disease (AD). This FDG-PET study investigates whether metabolic deficits in NL MH are associated with advancing maternal age at birth. Ninety-six NL individuals with FDG-PET were examined, including 36 MH, 24 PH, and 36 NH. Regional-to-whole brain gray matter standardized FDG uptake value ratios were examined for associations with parental age across groups using automated regions-of-interest and statistical parametric mapping. Groups were comparable for clinical and neuropsychological measures. Brain metabolism in AD-vulnerable regions was lower in MH compared to NH and PH, and negatively correlated with maternal age at birth only in MH. There were no associations between paternal age and metabolism in any group. Evidence for a maternally inherited, maternal age-related mechanism provides further insight on risk factors and genetic transmission in late-onset AD.

  16. 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.

  17. Dysregulation of skeletal muscle protein metabolism by alcohol

    PubMed Central

    Steiner, Jennifer L.

    2015-01-01

    Alcohol abuse, either by acute intoxication or prolonged excessive consumption, leads to pathological changes in many organs and tissues including skeletal muscle. As muscle protein serves not only a contractile function but also as a metabolic reserve for amino acids, which are used to support the energy needs of other tissues, its content is tightly regulated and dynamic. This review focuses on the etiology by which alcohol perturbs skeletal muscle protein balance and thereby over time produces muscle wasting and weakness. The preponderance of data suggest that alcohol primarily impairs global protein synthesis, under basal conditions as well as in response to several anabolic stimuli including growth factors, nutrients, and muscle contraction. This inhibitory effect of alcohol is mediated, at least in part, by a reduction in mTOR kinase activity via a mechanism that remains poorly defined but likely involves altered protein-protein interactions within mTOR complex 1. Furthermore, alcohol can exacerbate the decrement in mTOR and/or muscle protein synthesis present in other catabolic states. In contrast, alcohol-induced changes in muscle protein degradation, either global or via specific modulation of the ubiquitin-proteasome or autophagy pathways, are relatively inconsistent and may be model dependent. Herein, changes produced by acute intoxication versus chronic ingestion are contrasted in relation to skeletal muscle metabolism, and limitations as well as opportunities for future research are discussed. As the proportion of more economically developed countries ages and chronic illness becomes more prevalent, a better understanding of the etiology of biomedical consequences of alcohol use disorders is warranted. PMID:25759394

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

    PubMed Central

    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 NCFMTM (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. PMID:24717228

  19. The Ribosomal Protein-Mdm2-p53 Pathway and Energy Metabolism

    PubMed Central

    Deisenroth, Chad; Zhang, Yanping

    2011-01-01

    Cellular growth and division are two fundamental processes that are exquisitely sensitive and responsive to environmental fluctuations. One of the most energetically demanding functions of these processes is ribosome biogenesis, the key component to regulating overall protein synthesis and cell growth. Perturbations to ribosome biogenesis have been demonstrated to induce an acute stress response leading to p53 activation through the inhibition of Mdm2 by a number of ribosomal proteins. The energy status of a cell is a highly dynamic variable that naturally contributes to metabolic fluctuations, which can affect both the rates of ribosome biogenesis and p53 function. This, in turn, determines whether a cell is in an anabolic, growth-promoting state or a catabolic, growth-suppressing state. Here the authors integrate the known functions of p53 to postulate how changes in nutrient availability may induce the ribosomal protein–Mdm2-p53 signaling pathway to modulate p53-dependent metabolic regulation. PMID:21779508

  20. Dietary arginine affects energy metabolism through polyamine turnover in juvenile Atlantic salmon (Salmo salar).

    PubMed

    Andersen, Synne M; Holen, Elisabeth; Aksnes, Anders; Rønnestad, Ivar; Zerrahn, Jens-Erik; Espe, Marit

    2013-12-14

    In the present study, quadruplicate groups of juvenile Atlantic salmon (Salmo salar) were fed plant protein-based diets with increasing arginine inclusions (range 28·8-37·4 g/kg DM) to investigate whether arginine supplementation affects growth and lipid accumulation through an elevated polyamine turnover. Dietary lysine was held at a constant concentration, just below the requirement. All other amino acids were balanced and equal in the diets. Arginine supplementation increased protein and fat accretion, without affecting the hepatosomatic or visceralsomatic indices. Dietary arginine correlated with putrescine in the liver (R 0·78, P= 0·01) and with ornithine in the muscle, liver and plasma (P= 0·0002, 0·003 and 0·0002, respectively). The mRNA of ornithine decarboxylase, the enzyme producing putrescine, was up-regulated in the white adipose tissue of fish fed the high-arginine inclusion compared with those fed the low-arginine diet. Concomitantly, spermidine/spermine-(N1)-acetyltransferase, the rate-limiting enzyme for polyamine turnover that consumes acetyl-CoA, showed an increased activity in the liver of fish fed the arginine-supplemented diets. In addition, lower acetyl-CoA concentrations were observed in the liver of fish fed the high-arginine diet, while ATP, which is used in the process of synthesising spermidine and spermine, did not show a similar trend. Gene expression of the rate-limiting enzyme for β-oxidation of long-chain fatty acids, carnitine palmitoyl transferase-1, was up-regulated in the liver of fish fed the high-arginine diet. Taken together, the data support that increased dietary arginine activates polyamine turnover and β-oxidation in the liver of juvenile Atlantic salmon and may act to improve the metabolic status of the fish. PMID:23656796

  1. Dietary arginine affects energy metabolism through polyamine turnover in juvenile Atlantic salmon (Salmo salar).

    PubMed

    Andersen, Synne M; Holen, Elisabeth; Aksnes, Anders; Rønnestad, Ivar; Zerrahn, Jens-Erik; Espe, Marit

    2013-12-14

    In the present study, quadruplicate groups of juvenile Atlantic salmon (Salmo salar) were fed plant protein-based diets with increasing arginine inclusions (range 28·8-37·4 g/kg DM) to investigate whether arginine supplementation affects growth and lipid accumulation through an elevated polyamine turnover. Dietary lysine was held at a constant concentration, just below the requirement. All other amino acids were balanced and equal in the diets. Arginine supplementation increased protein and fat accretion, without affecting the hepatosomatic or visceralsomatic indices. Dietary arginine correlated with putrescine in the liver (R 0·78, P= 0·01) and with ornithine in the muscle, liver and plasma (P= 0·0002, 0·003 and 0·0002, respectively). The mRNA of ornithine decarboxylase, the enzyme producing putrescine, was up-regulated in the white adipose tissue of fish fed the high-arginine inclusion compared with those fed the low-arginine diet. Concomitantly, spermidine/spermine-(N1)-acetyltransferase, the rate-limiting enzyme for polyamine turnover that consumes acetyl-CoA, showed an increased activity in the liver of fish fed the arginine-supplemented diets. In addition, lower acetyl-CoA concentrations were observed in the liver of fish fed the high-arginine diet, while ATP, which is used in the process of synthesising spermidine and spermine, did not show a similar trend. Gene expression of the rate-limiting enzyme for β-oxidation of long-chain fatty acids, carnitine palmitoyl transferase-1, was up-regulated in the liver of fish fed the high-arginine diet. Taken together, the data support that increased dietary arginine activates polyamine turnover and β-oxidation in the liver of juvenile Atlantic salmon and may act to improve the metabolic status of the fish.

  2. The Role of the Renal Ammonia Transporter Rhcg in Metabolic Responses to Dietary Protein

    PubMed Central

    Bounoure, Lisa; Ruffoni, Davide; Müller, Ralph; Kuhn, Gisela Anna; Devuyst, Olivier

    2014-01-01

    High dietary protein imposes a metabolic acid load requiring excretion and buffering by the kidney. Impaired acid excretion in CKD, with potential metabolic acidosis, may contribute to the progression of CKD. Here, we investigated the renal adaptive response of acid excretory pathways in mice to high-protein diets containing normal or low amounts of acid-producing sulfur amino acids (SAA) and examined how this adaption requires the RhCG ammonia transporter. Diets rich in SAA stimulated expression of enzymes and transporters involved in mediating NH4+ reabsorption in the thick ascending limb of the loop of Henle. The SAA-rich diet increased diuresis paralleled by downregulation of aquaporin-2 (AQP2) water channels. The absence of Rhcg transiently reduced NH4+ excretion, stimulated the ammoniagenic pathway more strongly, and further enhanced diuresis by exacerbating the downregulation of the Na+/K+/2Cl− cotransporter (NKCC2) and AQP2, with less phosphorylation of AQP2 at serine 256. The high protein acid load affected bone turnover, as indicated by higher Ca2+ and deoxypyridinoline excretion, phenomena exaggerated in the absence of Rhcg. In animals receiving a high-protein diet with low SAA content, the kidney excreted alkaline urine, with low levels of NH4+ and no change in bone metabolism. Thus, the acid load associated with high-protein diets causes a concerted response of various nephron segments to excrete acid, mostly in the form of NH4+, that requires Rhcg. Furthermore, bone metabolism is altered by a high-protein acidogenic diet, presumably to buffer the acid load. PMID:24652796

  3. The impact of pre- and/or probiotics on human colonic metabolism: does it affect human health?

    PubMed

    De Preter, Vicky; Hamer, Henrike M; Windey, Karen; Verbeke, Kristin

    2011-01-01

    Since many years, the role of the colonic microbiota in maintaining the host's overall health and well-being has been recognized. Dietary modulation of the microbiota composition and activity has been achieved by the use of pre-, pro- and synbiotics. In this review, we will summarize the available evidence on the modification of bacterial metabolism by dietary intervention with pre-, pro- and synbiotics. Enhanced production of SCFA as a marker of increased saccharolytic fermentation is well documented in animal and in vitro studies. Decreased production of potentially toxic protein fermentation metabolites, such as sulfides, phenolic and indolic compounds, has been less frequently demonstrated. Besides, pre-, pro- and synbiotics also affect other metabolic pathways such as the deconjugation of secondary bile acids, bacterial enzyme activities and mineral absorption. Data from human studies are less conclusive. The emergence of new analytical techniques such as metabolite profiling has revealed new pathways affected by dietary intervention. However, an important challenge for current and future research is to relate changes in bacterial metabolism to concrete health benefits. Potential targets and expected benefits have been identified: reduced risk for the metabolic syndrome and prevention of colorectal cancer. PMID:21207512

  4. Dietary carbohydrate restriction induces a unique metabolic state positively affecting atherogenic dyslipidemia, fatty acid partitioning, and metabolic syndrome.

    PubMed

    Volek, Jeff S; Fernandez, Maria Luz; Feinman, Richard D; Phinney, Stephen D

    2008-09-01

    Abnormal fatty acid metabolism and dyslipidemia play an intimate role in the pathogenesis of metabolic syndrome and cardiovascular diseases. The availability of glucose and insulin predominate as upstream regulatory elements that operate through a collection of transcription factors to partition lipids toward anabolic pathways. The unraveling of the details of these cellular events has proceeded rapidly, but their physiologic relevance to lifestyle modification has been largely ignored. Here we highlight the role of dietary input, specifically carbohydrate intake, in the mechanism of metabolic regulation germane to metabolic syndrome. The key principle is that carbohydrate, directly or indirectly through the effect of insulin, controls the disposition of excess dietary nutrients. Dietary carbohydrate modulates lipolysis, lipoprotein assembly and processing and affects the relation between dietary intake of saturated fat intake and circulating levels. Several of these processes are the subject of intense investigation at the cellular level. We see the need to integrate these cellular mechanisms with results from low-carbohydrate diet trials that have shown reduced cardiovascular risk through improvement in hepatic, intravascular, and peripheral processing of lipoproteins, alterations in fatty acid composition, and reductions in other cardiovascular risk factors, notably inflammation. From the current state of the literature, however, low-carbohydrate diets are grounded in basic metabolic principles and the data suggest that some form of carbohydrate restriction is a candidate to be the preferred dietary strategy for cardiovascular health beyond weight regulation.

  5. MAPK14/p38α-dependent modulation of glucose metabolism affects ROS levels and autophagy during starvation

    PubMed Central

    Desideri, Enrico; Vegliante, Rolando; Cardaci, Simone; Nepravishta, Ridvan; Paci, Maurizio; Ciriolo, Maria Rosa

    2014-01-01

    Increased glycolytic flux is a common feature of many cancer cells, which have adapted their metabolism to maximize glucose incorporation and catabolism to generate ATP and substrates for biosynthetic reactions. Indeed, glycolysis allows a rapid production of ATP and provides metabolic intermediates required for cancer cells growth. Moreover, it makes cancer cells less sensitive to fluctuations of oxygen tension, a condition usually occurring in a newly established tumor environment. Here, we provide evidence for a dual role of MAPK14 in driving a rearrangement of glucose metabolism that contributes to limiting reactive oxygen species (ROS) production and autophagy activation in condition of nutrient deprivation. We demonstrate that MAPK14 is phosphoactivated during nutrient deprivation and affects glucose metabolism at 2 different levels: on the one hand, it increases SLC2A3 mRNA and protein levels, resulting in a higher incorporation of glucose within the cell. This event involves the MAPK14-mediated enhancement of HIF1A protein stability. On the other hand, MAPK14 mediates a metabolic shift from glycolysis to the pentose phosphate pathway (PPP) through the modulation of PFKFB3 (6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase 3) degradation by the proteasome. This event requires the presence of 2 distinct degradation sequences, KEN box and DSG motif Ser273, which are recognized by 2 different E3 ligase complexes. The mutation of either motif increases PFKFB3 resistance to starvation-induced degradation. The MAPK14-driven metabolic reprogramming sustains the production of NADPH, an important cofactor for many reduction reactions and for the maintenance of the proper intracellular redox environment, resulting in reduced levels of ROS. The final effect is a reduced activation of autophagy and an increased resistance to nutrient deprivation. PMID:25046111

  6. Myocardial Reloading After Extracorporeal Membrane Oxygenation Alters Substrate Metabolism While Promoting Protein Synthesis

    PubMed Central

    Kajimoto, Masaki; O'Kelly Priddy, Colleen M.; Ledee, Dolena R.; Xu, Chun; Isern, Nancy; Olson, Aaron K.; Rosiers, Christine Des; Portman, Michael A.

    2013-01-01

    Background Extracorporeal membrane oxygenation (ECMO) unloads the heart, providing a bridge to recovery in children after myocardial stunning. ECMO also induces stress which can adversely affect the ability to reload or wean the heart from the circuit. Metabolic impairments induced by altered loading and/or stress conditions may impact weaning. However, cardiac substrate and amino acid requirements upon weaning are unknown. We assessed the hypothesis that ventricular reloading with ECMO modulates both substrate entry into the citric acid cycle (CAC) and myocardial protein synthesis. Methods and Results Sixteen immature piglets (7.8 to 15.6 kg) were separated into 2 groups based on ventricular loading status: 8‐hour ECMO (UNLOAD) and postwean from ECMO (RELOAD). We infused into the coronary artery [2‐13C]‐pyruvate as an oxidative substrate and [13C6]‐L‐leucine as an indicator for amino acid oxidation and protein synthesis. Upon RELOAD, each functional parameter, which were decreased substantially by ECMO, recovered to near‐baseline level with the exclusion of minimum dP/dt. Accordingly, myocardial oxygen consumption was also increased, indicating that overall mitochondrial metabolism was reestablished. At the metabolic level, when compared to UNLOAD, RELOAD altered the contribution of various substrates/pathways to tissue pyruvate formation, favoring exogenous pyruvate versus glycolysis, and acetyl‐CoA formation, shifting away from pyruvate decarboxylation to endogenous substrate, presumably fatty acids. Furthermore, there was also a significant increase of tissue concentrations for all CAC intermediates (≈80%), suggesting enhanced anaplerosis, and of fractional protein synthesis rates (>70%). Conclusions RELOAD alters both cytosolic and mitochondrial energy substrate metabolism, while favoring leucine incorporation into protein synthesis rather than oxidation in the CAC. Improved understanding of factors governing these metabolic perturbations may

  7. Tumor redox metabolism correlation with the expression level of red fluorescent protein

    NASA Astrophysics Data System (ADS)

    Sha, Shuang; Wang, Anle; Lin, Qiaoya; Zhang, Zhihong

    2015-03-01

    The redox metabolism is variable and complicated with the progress of tumor development. Whether the tumor redox state will affect the exogenous gene expression or not, are still not clear now . To investigate the relationship between tumor endogenous redox state and the exogenous gene expression level, a far red fluorescent protein fRFP was used to monitor tumor cells proliferation and as an exogenous protein expression in tumors. NADH (nicotinamide adenine dinucleotide) and Fp (flavin protein) are two important coenzymes in the mitochondria respiratory chain, which can be as a standard representation for redox metabolism state. Three tumor subcutaneous models (melanoma, human pancreatic carcinoma and nasopharyngeal carcinoma) were used to observe their redox state and protein expression by our home-made redox scanner. The results showed that the distribution of fRFP fluorescent protein expression in the inner tumor regions are heterogeneous, and the fluorescent intensity of fRFP and the fluorescent intensity of NADH have high correlation. In addition, we also found the linear coefficient in three tumors are different, the value of coefficient is (R2 = 0.966 and R2 = 0.943) in melanoma, (R2 = 0.701 and R2 = 0.942) in human pancreatic carcinoma, and (R2 = 0.994) in nasopharyngeal carcinoma, respectively. From these results, we consider that the exogenous protein expression of fRFP in tumor had some relationship with the tumor redox state of NADH.

  8. Contact density affects protein evolutionary rate from bacteria to animals.

    PubMed

    Zhou, Tong; Drummond, D Allan; Wilke, Claus O

    2008-04-01

    The density of contacts or the fraction of buried sites in a protein structure is thought to be related to a protein's designability, and genes encoding more designable proteins should evolve faster than other genes. Several recent studies have tested this hypothesis but have found conflicting results. Here, we investigate how a gene's evolutionary rate is affected by its protein's contact density, considering the four species Escherichia coli, Saccharomyces cerevisiae, Drosophila melanogaster, and Homo sapiens. We find for all four species that contact density correlates positively with evolutionary rate, and that these correlations do not seem to be confounded by gene expression level. The strength of this signal, however, varies widely among species. We also study the effect of contact density on domain evolution in multidomain proteins and find that a domain's contact density influences the domain's evolutionary rate. Within the same protein, a domain with higher contact density tends to evolve faster than a domain with lower contact density. Our study provides evidence that contact density can increase evolutionary rates, and that it acts similarly on the level of entire proteins and of individual protein domains.

  9. Respiratory muscle strength and muscle endurance are not affected by acute metabolic acidemia.

    PubMed

    Nizet, Tessa A C; Heijdra, Yvonne F; van den Elshout, Frank J J; van de Ven, Marjo J T; Bosch, Frank H; Mulder, Paul H; Folgering, Hans Th M

    2009-11-01

    Respiratory muscle fatigue in asthma and chronic obstructive lung disease (COPD) contributes to respiratory failure with hypercapnia, and subsequent respiratory acidosis. Therapeutic induction of acute metabolic acidosis further increases the respiratory drive and, therefore, may diminish ventilatory failure and hypercapnia. On the other hand, it is known that acute metabolic acidosis can also negatively affect (respiratory) muscle function and, therefore, could lead to a deterioration of respiratory failure. Moreover, we reasoned that the impact of metabolic acidosis on respiratory muscle strength and respiratory muscle endurance could be more pronounced in COPD patients as compared to asthma patients and healthy subjects, due to already impaired respiratory muscle function. In this study, the effect of metabolic acidosis was studied on peripheral muscle strength, peripheral muscle endurance, airway resistance, and on arterial carbon dioxide tension (PaCO(2)). Acute metabolic acidosis was induced by administration of ammonium chloride (NH(4)Cl). The effect of metabolic acidosis was studied on inspiratory and expiratory muscle strength and on respiratory muscle endurance. Effects were studied in a randomized, placebo-controlled cross-over design in 15 healthy subjects (4 male; age 33.2 +/- 11.5 years; FEV(1) 108.3 +/- 16.2% predicted), 14 asthma patients (5 male; age 48.1 +/- 16.1 years; FEV(1) 101.6 +/- 15.3% predicted), and 15 moderate to severe COPD patients (9 male; age 62.8 +/- 6.8 years; FEV(1) 50.0 +/- 11.8% predicted). An acute metabolic acidemia of BE -3.1 mmol x L(-1) was induced. Acute metabolic acidemia did not significantly affect strength or endurance of respiratory and peripheral muscles, respectively. In all subjects airway resistance was significantly decreased after induction of metabolic acidemia (mean difference -0.1 kPa x sec x L(-1) [95%-CI: -0.1 - -0.02]. In COPD patients PaCO(2) was significantly lowered during metabolic acidemia (mean

  10. Protein oxidation affects proteolysis in a meat model system.

    PubMed

    Berardo, Alberto; Claeys, Erik; Vossen, Els; Leroy, Frédéric; De Smet, Stefaan

    2015-08-01

    The effect of hydrogen peroxide-induced protein oxidation and pH (4.8 and 5.2) on meat proteolysis was investigated in a meat model system for dry fermented sausages. In oxidised samples, increased protein carbonyl contents and decreased thiol concentrations were found. The initial concentration of protein carbonyls was significantly lower in oxidised samples at pH4.8 than in ones at pH5.2, but after ten days comparable levels were reached. The inhibition of proteolysis by the addition of a protease inhibitor cocktail did not influence protein oxidation. Yet, proteolysis was negatively affected by low pH values as well as by oxidation, resulting in a reduced release of amino acids during ripening.

  11. The Mediterranean diet: Effects on proteins that mediate fatty acid metabolism in the colon

    PubMed Central

    Djuric, Zora

    2012-01-01

    A Mediterranean diet appears to have health benefits in many domains of human health, mediated perhaps by its anti-inflammatory effects. Metabolism of fatty acids and subsequent eicosanoid production is a key mechanism by which a Mediterranean diet can exert anti-inflammatory effects. Both dietary fatty acids and fatty acid metabolism determine fatty acid availability for cyclooxygenase- and lipoxygenase-dependent production of eicosanoids, namely prostaglandins and leukotrienes. In dietary intervention studies and in observational studies of the Mediterranean diet, blood levels of fatty acids do reflect dietary intakes but are attenuated. Small differences in fatty acid levels, however, appear to be important, especially when exposures occur over long periods of time. This review summarizes how fat intakes from a Greek-style Mediterranean diet can be expected to affect fatty acid metabolizing proteins, with an emphasis on the metabolic pathways that lead to the formation of proinflammatory eicosanoids. The proteins involved in these pathways are ripe for investigation using proteomic approaches and may be targets for colon cancer prevention. PMID:22133197

  12. 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

  13. Apolipoprotein A-IV: a protein intimately involved in metabolism

    PubMed Central

    Wang, Fei; Kohan, Alison B.; Lo, Chun-Min; Liu, Min; Howles, Philip; Tso, Patrick

    2015-01-01

    The purpose of this review is to summarize our current understanding of the physiological roles of apoA-IV in metabolism, and to underscore the potential for apoA-IV to be a focus for new therapies aimed at the treatment of diabetes and obesity-related disorders. ApoA-IV is primarily synthesized by the small intestine, attached to chylomicrons by enterocytes, and secreted into intestinal lymph during fat absorption. In circulation, apoA-IV is associated with HDL and chylomicron remnants, but a large portion is lipoprotein free. Due to its anti-oxidative and anti-inflammatory properties, and because it can mediate reverse-cholesterol transport, proposed functions of circulating apoA-IV have been related to protection from cardiovascular disease. This review, however, focuses primarily on several properties of apoA-IV that impact other metabolic functions related to food intake, obesity, and diabetes. In addition to participating in triglyceride absorption, apoA-IV can act as an acute satiation factor through both peripheral and central routes of action. It also modulates glucose homeostasis through incretin-like effects on insulin secretion, and by moderating hepatic glucose production. While apoA-IV receptors remain to be conclusively identified, the latter modes of action suggest that this protein holds therapeutic promise for treating metabolic disease. PMID:25640749

  14. The Effect of Casein Protein Prior to Sleep on Fat Metabolism in Obese Men.

    PubMed

    Kinsey, Amber W; Cappadona, Stacy R; Panton, Lynn B; Allman, Brittany R; Contreras, Robert J; Hickner, Robert C; Ormsbee, Michael J

    2016-01-01

    We have previously shown that ingesting protein at night before sleep is either beneficial or non-detrimental to metabolism, health, and body composition in obese women. However, the overnight protein-induced lipolytic actions and mechanism for improved metabolism and body composition have not been fully established. Therefore, in a crossover design, twelve obese men (age, 27.0 ± 2.2 years) were randomly assigned to ingest (within 30 min of sleep) casein protein (CAS, 120 kcal) or a non-nutritive placebo (PLA) before going to sleep. Markers of fat metabolism (lipolysis, substrate utilization, growth hormone), insulin, glucose, resting energy expenditure (REE), and appetite (questionnaire and ghrelin) were measured. During sleep and the next morning, interstitial glycerol from the subcutaneous abdominal adipose tissue (SCAAT) was measured using microdialysis. There were no differences in SCAAT glycerol (overnight: CAS, 177.4 ± 26.7; PLA, 183.8 ± 20.2 μmol/L; morning: CAS, 171.6 ± 19.1; PLA, 161.5 ± 18.6 μmol/L), substrate utilization, REE, or any blood markers between CAS and PLA. Desire to eat was greater for CAS compared to baseline (p = 0.03), but not different from PLA (baseline: 39 ± 6, CAS: 62 ± 8, PLA: 55 ± 5 mm). CAS consumption before sleep did not affect fat or glucose metabolism, REE, or suppress appetite in hyperinsulemic obese men. CAS may be consumed before sleep without impeding overnight or morning fat metabolism in young, obese men.

  15. The Effect of Casein Protein Prior to Sleep on Fat Metabolism in Obese Men.

    PubMed

    Kinsey, Amber W; Cappadona, Stacy R; Panton, Lynn B; Allman, Brittany R; Contreras, Robert J; Hickner, Robert C; Ormsbee, Michael J

    2016-01-01

    We have previously shown that ingesting protein at night before sleep is either beneficial or non-detrimental to metabolism, health, and body composition in obese women. However, the overnight protein-induced lipolytic actions and mechanism for improved metabolism and body composition have not been fully established. Therefore, in a crossover design, twelve obese men (age, 27.0 ± 2.2 years) were randomly assigned to ingest (within 30 min of sleep) casein protein (CAS, 120 kcal) or a non-nutritive placebo (PLA) before going to sleep. Markers of fat metabolism (lipolysis, substrate utilization, growth hormone), insulin, glucose, resting energy expenditure (REE), and appetite (questionnaire and ghrelin) were measured. During sleep and the next morning, interstitial glycerol from the subcutaneous abdominal adipose tissue (SCAAT) was measured using microdialysis. There were no differences in SCAAT glycerol (overnight: CAS, 177.4 ± 26.7; PLA, 183.8 ± 20.2 μmol/L; morning: CAS, 171.6 ± 19.1; PLA, 161.5 ± 18.6 μmol/L), substrate utilization, REE, or any blood markers between CAS and PLA. Desire to eat was greater for CAS compared to baseline (p = 0.03), but not different from PLA (baseline: 39 ± 6, CAS: 62 ± 8, PLA: 55 ± 5 mm). CAS consumption before sleep did not affect fat or glucose metabolism, REE, or suppress appetite in hyperinsulemic obese men. CAS may be consumed before sleep without impeding overnight or morning fat metabolism in young, obese men. PMID:27472361

  16. The Effect of Casein Protein Prior to Sleep on Fat Metabolism in Obese Men

    PubMed Central

    Kinsey, Amber W.; Cappadona, Stacy R.; Panton, Lynn B.; Allman, Brittany R.; Contreras, Robert J.; Hickner, Robert C.; Ormsbee, Michael J.

    2016-01-01

    We have previously shown that ingesting protein at night before sleep is either beneficial or non-detrimental to metabolism, health, and body composition in obese women. However, the overnight protein-induced lipolytic actions and mechanism for improved metabolism and body composition have not been fully established. Therefore, in a crossover design, twelve obese men (age, 27.0 ± 2.2 years) were randomly assigned to ingest (within 30 min of sleep) casein protein (CAS, 120 kcal) or a non-nutritive placebo (PLA) before going to sleep. Markers of fat metabolism (lipolysis, substrate utilization, growth hormone), insulin, glucose, resting energy expenditure (REE), and appetite (questionnaire and ghrelin) were measured. During sleep and the next morning, interstitial glycerol from the subcutaneous abdominal adipose tissue (SCAAT) was measured using microdialysis. There were no differences in SCAAT glycerol (overnight: CAS, 177.4 ± 26.7; PLA, 183.8 ± 20.2 μmol/L; morning: CAS, 171.6 ± 19.1; PLA, 161.5 ± 18.6 μmol/L), substrate utilization, REE, or any blood markers between CAS and PLA. Desire to eat was greater for CAS compared to baseline (p = 0.03), but not different from PLA (baseline: 39 ± 6, CAS: 62 ± 8, PLA: 55 ± 5 mm). CAS consumption before sleep did not affect fat or glucose metabolism, REE, or suppress appetite in hyperinsulemic obese men. CAS may be consumed before sleep without impeding overnight or morning fat metabolism in young, obese men. PMID:27472361

  17. Exogenous administration of chronic corticosterone affects hepatic cholesterol metabolism in broiler chickens showing long or short tonic immobility.

    PubMed

    Liu, Jie; Duan, Yujing; Hu, Yun; Sun, Lili; Wang, Song; Fu, Wenyan; Ni, Yingdong; Zhao, Ruqian

    2016-01-01

    Tonic immobility (TI) is an innate characteristic of animals related to fear or stress response. Animals can be classified into long TI (LTI) and short TI (STI) phenotypes based on TI test duration. In this study, effect of TI phenotype, chronic corticosterone administration (CORT), and their interaction on cholesterol metabolism in liver was evaluated in broilers. LTI broilers showed higher level of cholesterol in liver compared to STI chickens (p<0.05), and CORT significantly increased hepatic cholesterol content (p<0.01). Real-time PCR results showed that both TI and CORT potentially altered ABCA1 and CYP7A1 gene expressions (0.05protein abundance in liver. However, TI phenotype only affected hepatic HMGCR protein expression, and LTI broilers showed higher level of HMGCR protein expression in liver than STI (p<0.05). These results indicate that chronic CORT administration causes hepatic cholesterol accumulation in broiler chickens mainly by enhancing cholesterol synthesis and uptake into liver. LTI chickens had higher amount of total cholesterol in liver, which might be associated with an increase of hepatic HMGCR protein expression. However, there is no interaction between TI and CORT on cholesterol metabolism in liver of broilers.

  18. [Effects of enhanced UV-B radiation on physiological metabolism, DNA and protein of crops: a review].

    PubMed

    Li, Yuan; He, Yongmei; Zu, Yanqun

    2006-01-01

    Ozone depletion in stratosphere has led to the increase of solar UV-B radiation reaching to the earth surface, which would affect crops to various extents. This review dealt with the effects of enhanced UV-B radiation on the physiological metabolism, DNA damage and protein content of crops. Enhanced UV-B radiation could increase crops' flavonoid content but decrease their chlorophyll content and photosynthesis, induce gene change, and result in DNA damage and change of protein content.

  19. Effects of supplemental protein on acid-base status and calcium metabolism of nonlactating Jersey cows.

    PubMed

    Wang, C; Beede, D K

    1990-11-01

    The objective was to study effects of 11, 15, and 19% dietary CP on acid-base status, Ca balance, and metabolic responses to intravenous infusion of disodium EDTA. Dietary protein content was increased by supplementation of hydrolyzed feather meal and distillers dried grains with solubles to a concentrate combined with cottonseed hulls (40:60). Six nonlactating, nonpregnant multiparous Jersey cows (average 6.7 yr old) were used in two balanced 3 x 3 Latin squares with 24-d periods. Increasing supplemental CP decreased blood base excess, urinary titratable base, and net base excretion, but increased urinary ammonium excretion. Calcium excretion and balance were not affected by supplemental CP. Analysis to detect heterogeneity of regression showed that response of plasma EDTA-free Ca to EDTA infusion over time was not different among treatments. Increasing supplemental protein induced mild acidosis but did not affect Ca balance or responses to Ca removal from blood (via EDTA infusion) of non-lactating cows.

  20. Role of Protein Farnesylation in Burn-Induced Metabolic Derangements and Insulin Resistance in Mouse Skeletal Muscle

    PubMed Central

    Tanaka, Tomokazu; Kramer, Joshua; Yu, Yong-Ming; Fischman, Alan J.; Martyn, J. A. Jeevendra; Tompkins, Ronald G.; Kaneki, Masao

    2015-01-01

    Objective Metabolic derangements, including insulin resistance and hyperlactatemia, are a major complication of major trauma (e.g., burn injury) and affect the prognosis of burn patients. Protein farnesylation, a posttranslational lipid modification of cysteine residues, has been emerging as a potential component of inflammatory response in sepsis. However, farnesylation has not yet been studied in major trauma. To study a role of farnesylation in burn-induced metabolic aberration, we examined the effects of farnesyltransferase (FTase) inhibitor, FTI-277, on burn-induced insulin resistance and metabolic alterations in mouse skeletal muscle. Methods A full thickness burn (30% total body surface area) was produced under anesthesia in male C57BL/6 mice at 8 weeks of age. After the mice were treated with FTI-277 (5 mg/kg/day, IP) or vehicle for 3 days, muscle insulin signaling, metabolic alterations and inflammatory gene expression were evaluated. Results Burn increased FTase expression and farnesylated proteins in mouse muscle compared with sham-burn at 3 days after burn. Simultaneously, insulin-stimulated phosphorylation of insulin receptor (IR), insulin receptor substrate (IRS)-1, Akt and GSK-3β was decreased. Protein expression of PTP-1B (a negative regulator of IR-IRS-1 signaling), PTEN (a negative regulator of Akt-mediated signaling), protein degradation and lactate release by muscle, and plasma lactate levels were increased by burn. Burn-induced impaired insulin signaling and metabolic dysfunction were associated with increased inflammatory gene expression. These burn-induced alterations were reversed or ameliorated by FTI-277. Conclusions Our data demonstrate that burn increased FTase expression and protein farnesylation along with insulin resistance, metabolic alterations and inflammatory response in mouse skeletal muscle, all of which were prevented by FTI-277 treatment. These results indicate that increased protein farnesylation plays a pivotal role in burn

  1. Increased phloem transport of S-methylmethionine positively affects sulfur and nitrogen metabolism and seed development in pea plants.

    PubMed

    Tan, Qiumin; Zhang, Lizhi; Grant, Jan; Cooper, Pauline; Tegeder, Mechthild

    2010-12-01

    Seeds of grain legumes are important energy and food sources for humans and animals. However, the yield and quality of legume seeds are limited by the amount of sulfur (S) partitioned to the seeds. The amino acid S-methylmethionine (SMM), a methionine derivative, has been proposed to be an important long-distance transport form of reduced S, and we analyzed whether SMM phloem loading and source-sink translocation are important for the metabolism and growth of pea (Pisum sativum) plants. Transgenic plants were produced in which the expression of a yeast SMM transporter, S-Methylmethionine Permease1 (MMP1, YLL061W), was targeted to the phloem and seeds. Phloem exudate analysis showed that concentrations of SMM are elevated in MMP1 plants, suggesting increased phloem loading. Furthermore, expression studies of genes involved in S transport and metabolism in source organs, as well as xylem sap analyses, support that S uptake and assimilation are positively affected in MMP1 roots. Concomitantly, nitrogen (N) assimilation in root and leaf and xylem amino acid profiles were changed, resulting in increased phloem loading of amino acids. When investigating the effects of increased S and N phloem transport on seed metabolism, we found that protein levels were improved in MMP1 seeds. In addition, changes in SMM phloem loading affected plant growth and seed number, leading to an overall increase in seed S, N, and protein content in MMP1 plants. Together, these results suggest that phloem loading and source-sink partitioning of SMM are important for plant S and N metabolism and transport as well as seed set.

  2. Text mining for metabolic pathways, signaling cascades, and protein networks.

    PubMed

    Hoffmann, Robert; Krallinger, Martin; Andres, Eduardo; Tamames, Javier; Blaschke, Christian; Valencia, Alfonso

    2005-05-10

    The complexity of the information stored in databases and publications on metabolic and signaling pathways, the high throughput of experimental data, and the growing number of publications make it imperative to provide systems to help the researcher navigate through these interrelated information resources. Text-mining methods have started to play a key role in the creation and maintenance of links between the information stored in biological databases and its original sources in the literature. These links will be extremely useful for database updating and curation, especially if a number of technical problems can be solved satisfactorily, including the identification of protein and gene names (entities in general) and the characterization of their types of interactions. The first generation of openly accessible text-mining systems, such as iHOP (Information Hyperlinked over Proteins), provides additional functions to facilitate the reconstruction of protein interaction networks, combine database and text information, and support the scientist in the formulation of novel hypotheses. The next challenge is the generation of comprehensive information regarding the general function of signaling pathways and protein interaction networks. PMID:15886388

  3. Changes in contralateral protein metabolism following unilateral sciatic nerve section

    SciTech Connect

    Menendez, J.A.; Cubas, S.C.

    1990-03-01

    Changes in nerve biochemistry, anatomy, and function following injuries to the contralateral nerve have been repeatedly reported, though their significance is unknown. The most likely mechanisms for their development are either substances carried by axoplasmic flow or electrically transmitted signals. This study analyzes which mechanism underlies the development of a contralateral change in protein metabolism. The incorporation of labelled amino acids (AA) into proteins of both sciatic nerves was assessed by liquid scintillation after an unilateral section. AA were offered locally for 30 min to the distal stump of the sectioned nerves and at homologous levels of the intact contralateral nerves. At various times, from 1 to 24 h, both sciatic nerves were removed and the proteins extracted with trichloroacetic acid (TCA). An increase in incorporation was found in both nerves 14-24 h after section. No difference existed between sectioned and intact nerves, which is consistent with the contralateral effect. Lidocaine, but not colchicine, when applied previously to the nerves midway between the sectioning site and the spinal cord, inhibited the contralateral increase in AA incorporation. It is concluded that electrical signals, crossing through the spinal cord, are responsible for the development of the contralateral effect. Both the nature of the proteins and the significance of the contralateral effect are matters for speculation.

  4. Acute responses of muscle protein metabolism to reduced blood flow reflect metabolic priorities for homeostasis.

    PubMed

    Zhang, Xiao-Jun; Irtun, Oivind; Chinkes, David L; Wolfe, Robert R

    2008-03-01

    The present experiment was designed to measure the synthetic and breakdown rates of muscle protein in the hindlimb of rabbits with or without clamping the femoral artery. l-[ring-(13)C(6)]phenylalanine was infused as a tracer for measurement of muscle protein kinetics by means of an arteriovenous model, tracer incorporation, and tracee release methods. The ultrasonic flowmeter, dye dilution, and microsphere methods were used to determine the flow rates in the femoral artery, in the leg, and in muscle capillary, respectively. The femoral artery flow accounted for 65% of leg flow. A 50% reduction in the femoral artery flow reduced leg flow by 28% and nutritive flow by 26%, which did not change protein synthetic or breakdown rate in leg muscle. Full clamp of the femoral artery reduced leg flow by 42% and nutritive flow by 59%, which decreased (P < 0.05) both the fractional synthetic rate from 0.19 +/- 0.05 to 0.14 +/- 0.03%/day and fractional breakdown rate from 0.28 +/- 0.07 to 0.23 +/- 0.09%/day of muscle protein. Neither the partial nor full clamp reduced (P = 0.27-0.39) the intracellular phenylalanine concentration or net protein balance in leg muscle. We conclude that the flow threshold to cause a fall of protein turnover rate in leg muscle was a reduction of 30-40% of the leg flow. The acute responses of muscle protein kinetics to the reductions in blood flow reflected the metabolic priorities to maintain muscle homeostasis. These findings cannot be extrapolated to more chronic conditions without experimental validation. PMID:18089763

  5. Nitrogen-Sparing Mechanisms in Chlamydomonas Affect the Transcriptome, the Proteome, and Photosynthetic Metabolism[W

    PubMed Central

    Schmollinger, Stefan; Mühlhaus, Timo; Boyle, Nanette R.; Blaby, Ian K.; Casero, David; Mettler, Tabea; Moseley, Jeffrey L.; Kropat, Janette; Sommer, Frederik; Strenkert, Daniela; Hemme, Dorothea; Pellegrini, Matteo; Grossman, Arthur R.; Stitt, Mark; Schroda, Michael; Merchant, Sabeeha S.

    2014-01-01

    Nitrogen (N) is a key nutrient that limits global primary productivity; hence, N-use efficiency is of compelling interest in agriculture and aquaculture. We used Chlamydomonas reinhardtii as a reference organism for a multicomponent analysis of the N starvation response. In the presence of acetate, respiratory metabolism is prioritized over photosynthesis; consequently, the N-sparing response targets proteins, pigments, and RNAs involved in photosynthesis and chloroplast function over those involved in respiration. Transcripts and proteins of the Calvin-Benson cycle are reduced in N-deficient cells, resulting in the accumulation of cycle metabolic intermediates. Both cytosolic and chloroplast ribosomes are reduced, but via different mechanisms, reflected by rapid changes in abundance of RNAs encoding chloroplast ribosomal proteins but not cytosolic ones. RNAs encoding transporters and enzymes for metabolizing alternative N sources increase in abundance, as is appropriate for the soil environmental niche of C. reinhardtii. Comparison of the N-replete versus N-deplete proteome indicated that abundant proteins with a high N content are reduced in N-starved cells, while the proteins that are increased have lower than average N contents. This sparing mechanism contributes to a lower cellular N/C ratio and suggests an approach for engineering increased N-use efficiency. PMID:24748044

  6. Non-Genomic Origins of Proteins and Metabolism

    NASA Technical Reports Server (NTRS)

    Pohorille, Andrew

    2003-01-01

    It is proposed that evolution of inanimate matter to cells endowed with a nucleic acid- based coding of genetic information was preceded by an evolutionary phase, in which peptides not coded by nucleic acids were able to self-organize into networks capable of evolution towards increasing metabolic complexity. Recent findings that truly different, simple peptides (Keefe and Szostak, 2001) can perform the same function (such as ATP binding) provide experimental support for this mechanism of early protobiological evolution. The central concept underlying this mechanism is that the reproduction of cellular functions alone was sufficient for self-maintenance of protocells, and that self- replication of macromolecules was not required at this stage of evolution. The precise transfer of information between successive generations of the earliest protocells was unnecessary and, possibly, undesirable. The key requirement in the initial stage of protocellular evolution was an ability to rapidly explore a large number of protein sequences in order to discover a set of molecules capable of supporting self- maintenance and growth of protocells. Undoubtedly, the essential protocellular functions were carried out by molecules not nearly as efficient or as specific as contemporary proteins. Many, potentially unrelated sequences could have performed each of these functions at an evolutionarily acceptable level. As evolution progressed, however proteins must have performed their functions with increasing efficiency and specificity. This, in turn, put additional constraints on protein sequences and the fraction of proteins capable of performing their functions at the required level decreased. At some point, the likelihood of generating a sufficiently efficient set of proteins through a non-coded synthesis was so small that further evolution was not possible without storing information about the sequences of these proteins. Beyond this point, further evolution required coupling between

  7. Marginal B-6 intake affects protein synthesis in rat tissues

    SciTech Connect

    Sampson, D.A.; Kretsch, M.J.; Young, L.A.; Jansen, G.R.

    1986-03-05

    The role of vitamin B-6 in amino acid metabolism suggests that inadequate B-6 intake may impair protein synthesis. To test this hypothesis, 30 male rats (initially 227 g) were fed AIN76A diets that contained control, marginal or devoid levels of B-6 (5.8, 1.2 or 0.1 mg B-6/kg diet, by analysis) ad libitum for 9 weeks. Protein synthesis rates (PSRs) were measured in liver, kidney and calf muscle using a flooding dose of /sup 3/H-phenylalanine. Marginal and control groups ate and gained weight at similar rates. The marginal diet did not elevate xanthurenic acid (XA) excretion following a tryptophan load. However, marginal B-6 intake did depress liver PSR by 29% (2182 vs 1549 mg/day, P<.05), liver wet weight by 15% (19.0 vs 16.1 g, P<.05) and muscle PSR by 23% (3.0 vs 2.3%/day, P<.10). Unexpectedly, marginal B-6 intake increased PSR in kidney 47% (90 vs 132 mg/day, P<.05). The devoid diet, which increased XA excretion following a tryptophan load by more than 3-fold, depressed PSRs 56% in liver and 31% in muscle. However, the devoid diet decreased food intake by 40% (25.0 vs 15.0 g/day); therefore effects of devoid B-6 intake on PSRs may have been confounded by deficits in protein-energy intake in devoid vs control groups. These data demonstrate that marginal B-6 intake alters protein synthesis in tissues of the rat.

  8. 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

  9. 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

  10. Xylitol Affects the Intestinal Microbiota and Metabolism of Daidzein in Adult Male Mice

    PubMed Central

    Tamura, Motoi; Hoshi, Chigusa; Hori, Sachiko

    2013-01-01

    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. PMID:24336061

  11. 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.

  12. Modifying metabolically sensitive histone marks by inhibiting glutamine metabolism affects gene expression and alters cancer cell phenotype.

    PubMed

    Simpson, Natalie E; Tryndyak, Volodymyr P; Pogribna, Marta; Beland, Frederick A; Pogribny, Igor P

    2012-12-01

    The interplay of metabolism and epigenetic regulatory mechanisms has become a focal point for a better understanding of cancer development and progression. In this study, we have acquired data supporting previous observations that demonstrate glutamine metabolism affects histone modifications in human breast cancer cell lines. Treatment of non-invasive epithelial (T-47D and MDA-MB-361) and invasive mesenchymal (MDA-MB-231 and Hs-578T) breast cancer cell lines with the glutaminase inhibitor, Compound 968, resulted in cytotoxicity in all cell lines, with the greatest effect being observed in MDA-MB-231 breast cancer cells. Compound 968-treatment induced significant downregulation of 20 critical cancer-related genes, the majority of which are anti-apoptotic and/or promote metastasis, including AKT, BCL2, BCL2L1, CCND1, CDKN3, ERBB2, ETS1, E2F1, JUN, KITLG, MYB, and MYC. Histone H3K4me3, a mark of transcriptional activation, was reduced at the promoters of all but one of these critical cancer genes. The decrease in histone H3K4me3 at global and gene-specific levels correlated with reduced expression of SETD1 and ASH2L, genes encoding the histone H3K4 methyltransferase complex. Further, the expression of other epigenetic regulatory genes, known to be downregulated during apoptosis (e.g., DNMT1, DNMT3B, SETD1 and SIRT1), was also downregulated by Compound 968. These changes in gene expression and histone modifications were accompanied by the activation of apoptosis, and decreased invasiveness and resistance of MDA-MB-231 cells to chemotherapeutic drug doxorubicin. The results of this study provide evidence to a link between cytotoxicity caused by inhibiting glutamine metabolism with alterations of the epigenome of breast cancer cells and suggest that modification of intracellular metabolism may enhance the efficiency of epigenetic therapy. PMID:23117580

  13. 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.

  14. Wilson disease: changes in methionine metabolism and inflammation affect global DNA methylation in early liver disease

    PubMed Central

    Medici, Valentina; Shibata, Noreene M.; Kharbanda, Kusum K.; LaSalle, Janine M.; Woods, Rima; Liu, Sarah; Engelberg, Jesse A.; Devaraj, Sridevi; Török, Natalie J.; Jiang, Joy X.; Havel, Peter J.; Lönnerdal, Bo; Kim, Kyoungmi; Halsted, Charles H.

    2012-01-01

    Hepatic methionine metabolism may play an essential role in regulating methylation status and liver injury in Wilson disease (WD) through the inhibition of S-adenosylhomocysteine hydrolase (SAHH) by copper (Cu) and the consequent accumulation of S-adenosylhomocysteine (SAH). We studied the transcript levels of selected genes related to liver injury, levels of SAHH, SAH, DNA methyltransferases genes (Dnmt1, Dnmt3a, Dnmt3b) and global DNA methylation in the tx-j mouse (tx-j), an animal model of WD. Findings were compared to those in control C3H mice, and in response to Cu chelation by penicillamine (PCA) and dietary supplementation of the methyl donor betaine to modulate inflammatory and methylation status. Transcript levels of selected genes related to endoplasmic reticulum stress, lipid synthesis, and fatty acid oxidation were down-regulated at baseline in tx-j mice, further down-regulated in response to PCA, and showed little to no response to betaine. Hepatic Sahh transcript and protein levels were reduced in tx-j mice with consequent increase of SAH levels. Hepatic Cu accumulation was associated with inflammation, as indicated by histopathology and elevated serum ALT and liver tumor necrosis factor alpha (Tnf-α) levels. Dnmt3b was down-regulated in tx-j mice together with global DNA hypomethylation. PCA treatment of tx-j mice reduced Tnf-α and ALT levels, betaine treatment increased S-adenosylmethionine and up-regulated Dnmt3b levels, and both treatments restored global DNA methylation levels. Conclusion: reduced hepatic Sahh expression was associated with increased liver SAH levels in the tx-j model of WD, with consequent global DNA hypomethylation. Increased global DNA methylation was achieved by reducing inflammation by Cu chelation or by providing methyl groups. We propose that increased SAH levels and inflammation affect widespread epigenetic regulation of gene expression in WD. PMID:22945834

  15. Dopamine induces the accumulation of insoluble prion protein and affects autophagic flux

    PubMed Central

    da Luz, Marcio H. M.; Peres, Italo T.; Santos, Tiago G.; Martins, Vilma R.; Icimoto, Marcelo Y.; Lee, Kil S.

    2015-01-01

    Accumulation of protein aggregates is a histopathological hallmark of several neurodegenerative diseases, but in most cases the aggregation occurs without defined mutations or clinical histories, suggesting that certain endogenous metabolites can promote aggregation of specific proteins. One example that supports this hypothesis is dopamine and its metabolites. Dopamine metabolism generates several oxidative metabolites that induce aggregation of α-synuclein, and represents the main etiology of Parkinson's diseases. Because dopamine and its metabolites are unstable and can be highly reactive, we investigated whether these molecules can also affect other proteins that are prone to aggregate, such as cellular prion protein (PrPC). In this study, we showed that dopamine treatment of neuronal cells reduced the number of viable cells and increased the production of reactive oxygen species (ROS) as demonstrated in previous studies. Overall PrPC expression level was not altered by dopamine treatment, but its unglycosylated form was consistently reduced at 100 μM of dopamine. At the same concentration, the level of phosphorylated mTOR and 4EBP1 was also reduced. Moreover, dopamine treatment decreased the solubility of PrPC, and increased its accumulation in autophagosomal compartments with concomitant induction of LC3-II and p62/SQSTM1 levels. In vitro oxidation of dopamine promoted formation of high-order oligomers of recombinant prion protein. These results suggest that dopamine metabolites alter the conformation of PrPC, which in turn is sorted to degradation pathway, causing autophagosome overload and attenuation of protein synthesis. Accumulation of PrPC aggregates is an important feature of prion diseases. Thus, this study brings new insight into the dopamine metabolism as a source of endogenous metabolites capable of altering PrPC solubility and its subcellular localization. PMID:25698927

  16. Thermal conditions experienced during differentiation affect metabolic and contractile phenotypes of mouse myotubes.

    PubMed

    Little, Alex G; Seebacher, Frank

    2016-09-01

    Central pathways regulate metabolic responses to cold in endotherms to maintain relatively stable internal core body temperatures. However, peripheral muscles routinely experience temperatures lower than core body temperature, so that it would be advantageous for peripheral tissues to respond to temperature changes independently from core body temperature regulation. Early developmental conditions can influence offspring phenotypes, and here we tested whether developing muscle can compensate locally for the effects of cold exposure independently from central regulation. Muscle myotubes originate from undifferentiated myoblasts that are laid down during embryogenesis. We show that in a murine myoblast cell line (C2C12), cold exposure (32°C) increased myoblast metabolic flux compared with 37°C control conditions. Importantly, myotubes that differentiated at 32°C compensated for the thermodynamic effects of low temperature by increasing metabolic rates, ATP production, and glycolytic flux. Myotube responses were also modulated by the temperatures experienced by "parent" myoblasts. Myotubes that differentiated under cold exposure increased activity of the AMP-stimulated protein kinase (AMPK), which may mediate metabolic changes in response cold exposure. Moreover, cold exposure shifted myosin heavy chains from slow to fast, presumably to overcome slower contractile speeds resulting from low temperatures. Adjusting thermal sensitivities locally in peripheral tissues complements central thermoregulation and permits animals to maintain function in cold environments. Muscle also plays a major metabolic role in adults, so that developmental responses to cold are likely to influence energy expenditure later in life. PMID:27385733

  17. Nitrogen metabolism, digestive parameters, and protein requirements for the maintenance of buffalo growth.

    PubMed

    Machado, Erica; Yoshimura, Emerson Henri; Santos, Nadine Woruby; Agustinho, Bruna Calvo; Pereira, Lucelia de Moura; Samensari, Rafael Barreiros; de Aguiar, Silvia Cristina; Zeoula, Lucia Maria

    2016-02-01

    The objectives of this study were to evaluate the effect of crude protein (CP) levels in the diet of growing female buffaloes on nitrogen metabolism and estimate protein requirements for maintenance. Four female buffaloes were used, cannulated in the rumen, with an average initial body weight (BW) of 355 ± 3.5 kg, in a Latin square (4 × 4) with four animals and four levels of CP in the diet (70, 90, 110, and 130 g/kg dry matter (DM)) composed of corn silage and concentrate. The increase in protein intake with increasing levels of dietary CP resulted in a higher concentration of ammonia in the rumen and higher ruminal disappearance of PB. However, omasal flow of protein increased linearly as did the efficiency of microbial protein synthesis. The CP levels affected DM intake and other nutrients positively, but there was no effect on nutrient total digestibility. Nitrogen (N) balance, when expressed relative to N intake, had an average value of 48.5 % observed across. The protein requirement for the maintenance of growing female buffaloes was 4.6 g CP/kg BW(0.75). PMID:26590610

  18. 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.

  19. 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

  20. Protein Analysis of Sapienic Acid-Treated Porphyromonas gingivalis Suggests Differential Regulation of Multiple Metabolic Pathways

    PubMed Central

    Dawson, Deborah V.; Blanchette, Derek R.; Drake, David R.; Wertz, Philip W.; Brogden, Kim A.

    2015-01-01

    ABSTRACT Lipids endogenous to skin and mucosal surfaces exhibit potent antimicrobial activity against Porphyromonas gingivalis, an important colonizer of the oral cavity implicated in periodontitis. Our previous work demonstrated the antimicrobial activity of the fatty acid sapienic acid (C16:1Δ6) against P. gingivalis and found that sapienic acid treatment alters both protein and lipid composition from those in controls. In this study, we further examined whole-cell protein differences between sapienic acid-treated bacteria and untreated controls, and we utilized open-source functional association and annotation programs to explore potential mechanisms for the antimicrobial activity of sapienic acid. Our analyses indicated that sapienic acid treatment induces a unique stress response in P. gingivalis resulting in differential expression of proteins involved in a variety of metabolic pathways. This network of differentially regulated proteins was enriched in protein-protein interactions (P = 2.98 × 10−8), including six KEGG pathways (P value ranges, 2.30 × 10−5 to 0.05) and four Gene Ontology (GO) molecular functions (P value ranges, 0.02 to 0.04), with multiple suggestive enriched relationships in KEGG pathways and GO molecular functions. Upregulated metabolic pathways suggest increases in energy production, lipid metabolism, iron acquisition and processing, and respiration. Combined with a suggested preferential metabolism of serine, which is necessary for fatty acid biosynthesis, these data support our previous findings that the site of sapienic acid antimicrobial activity is likely at the bacterial membrane. IMPORTANCE P. gingivalis is an important opportunistic pathogen implicated in periodontitis. Affecting nearly 50% of the population, periodontitis is treatable, but the resulting damage is irreversible and eventually progresses to tooth loss. There is a great need for natural products that can be used to treat and/or prevent the overgrowth of

  1. Genetic perturbation of key central metabolic genes extends lifespan in Drosophila and affects response to dietary restriction.

    PubMed

    Talbert, Matthew E; Barnett, Brittany; Hoff, Robert; Amella, Maria; Kuczynski, Kate; Lavington, Erik; Koury, Spencer; Brud, Evgeny; Eanes, Walter F

    2015-09-22

    There is a connection between nutrient inputs, energy-sensing pathways, lifespan variation and aging. Despite the role of metabolic enzymes in energy homeostasis and their metabolites as nutrient signals, little is known about how their gene expression impacts lifespan. In this report, we use P-element mutagenesis in Drosophila to study the effect on lifespan of reductions in expression of seven central metabolic enzymes, and contrast the effects on normal diet and dietary restriction. The major observation is that for five of seven genes, the reduction of gene expression extends lifespan on one or both diets. Two genes are involved in redox balance, and we observe that lower activity genotypes significantly extend lifespan. The hexokinases also show extension of lifespan with reduced gene activity. Since both affect the ATP/ADP ratio, this connects with the role of AMP-activated protein kinase as an energy sensor in regulating lifespan and mediating caloric restriction. These genes possess significant expression variation in natural populations, and our experimental genotypes span this level of natural activity variation. Our studies link the readout of energy state with the perturbation of the genes of central metabolism and demonstrate their effect on lifespan.

  2. The stoichiometry of the chloroplast ATP synthase oligomer III in Chlamydomonas reinhardtii is not affected by the metabolic state.

    PubMed

    Meyer Zu Tittingdorf, Jürgen M W; Rexroth, Sascha; Schäfer, Eva; Schlichting, Ralf; Giersch, Christoph; Dencher, Norbert A; Seelert, Holger

    2004-11-01

    The chloroplast H(+)-ATP synthase is a key component for the energy supply of higher plants and green algae. An oligomer of identical protein subunits III is responsible for the conversion of an electrochemical proton gradient into rotational motion. It is highly controversial if the oligomer III stoichiometry is affected by the metabolic state of any organism. Here, the intact oligomer III of the ATP synthase from Chlamydomonas reinhardtii has been isolated for the first time. Due to the importance of the subunit III stoichiometry for energy conversion, a gradient gel system was established to distinguish oligomers with different stoichiometries. With this methodology, a possible alterability of the stoichiometry in respect to the metabolic state of the cells was examined. Several growth parameters, i.e., light intensity, pH value, carbon source, and CO(2) concentration, were varied to determine their effects on the stoichiometry. Contrary to previous suggestions for E. coli, the oligomer III of the chloroplast H(+)-ATP synthase always consists of a constant number of monomers over a wide range of metabolic states. Furthermore, mass spectrometry indicates that subunit III from C. reinhardtii is not modified posttranslationally. Data suggest a subunit III stoichiometry of the algae ATP synthase divergent from higher plants.

  3. [THE ANALYSIS OF INDICATORS OF MINERAL METABOLISM IN PATIENTS WITH DEGENERATIVE DYSTROPHIC AFFECTIONS OF JOINTS].

    PubMed

    Gasanova, A G; Matveeva, E L; Spirkina, E S

    2015-12-01

    The analysis of indicators of mineral metabolism in patients with degenerative dystrophic affections of joints demonstrated that under development of osteoarthrosis process the alteration of indicators of concentration of electrolytes in blood serum, urine and synovial fluid occurs. The stage II of process is characterized by maximal alterations of indicators. The indicator of relationship between concentration of phosphate-ion and index of phosphatases of blood serum turned out the significant coefficient of correlation. PMID:27032248

  4. [THE ANALYSIS OF INDICATORS OF MINERAL METABOLISM IN PATIENTS WITH DEGENERATIVE DYSTROPHIC AFFECTIONS OF JOINTS].

    PubMed

    Gasanova, A G; Matveeva, E L; Spirkina, E S

    2015-12-01

    The analysis of indicators of mineral metabolism in patients with degenerative dystrophic affections of joints demonstrated that under development of osteoarthrosis process the alteration of indicators of concentration of electrolytes in blood serum, urine and synovial fluid occurs. The stage II of process is characterized by maximal alterations of indicators. The indicator of relationship between concentration of phosphate-ion and index of phosphatases of blood serum turned out the significant coefficient of correlation.

  5. Defining meal requirements for protein to optimize metabolic roles of amino acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dietary protein provides essential amino acids (EAAs) for the synthesis of new proteins plus an array of other metabolic functions; many of these functions are sensitive to postprandial plasma and intracellular amino acid concentrations. Recent research has focused on amino acids as metabolic signal...

  6. Defining meal requirements for protein to optimize metabolic roles of amino acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dietary protein provides essential amino acids (EAA) for the synthesis of new proteins plus an array of other metabolic functions; many of these functions are sensitive to post-prandial plasma and intracellular amino acid concentrations. Recent research has focused on amino acids as metabolic signal...

  7. Membrane bending by protein crowding is affected by protein lateral confinement.

    PubMed

    Derganc, Jure; Čopič, Alenka

    2016-06-01

    Crowding of asymmetrically-distributed membrane proteins has been recently recognized as an important factor in remodeling of biological membranes, for example during transport vesicle formation. In this paper, we theoretically analyze the effect of protein crowding on membrane bending and examine its dependence on protein size, shape, transmembrane asymmetry and lateral confinement. We consider three scenarios of protein lateral organization, which are highly relevant for cellular membranes in general: freely diffusing membrane proteins without lateral confinement, the presence of a diffusion barrier and interactions with a vesicular coat. We show that protein crowding affects vesicle formation even if the proteins are distributed symmetrically across the membrane and that this effect depends significantly on lateral confinement. The largest crowding effect is predicted for the proteins that are confined to the forming vesicle by a diffusion barrier. We calculate the bending properties of a crowded membrane and find that its spontaneous curvature depends primarily on the degree of transmembrane asymmetry, and its effective bending modulus on the type of lateral confinement. Using the example of COPII vesicle formation from the endoplasmic reticulum, we analyze the energetic cost of vesicle formation. The results provide a novel insight into the effects of lateral and transmembrane organization of membrane proteins, and can guide data interpretation and future experimental approaches.

  8. The Regulatory Protein RosR Affects Rhizobium leguminosarum bv. trifolii Protein Profiles, Cell Surface Properties, and Symbiosis with Clover

    PubMed Central

    Rachwał, Kamila; Boguszewska, Aleksandra; Kopcińska, Joanna; Karaś, Magdalena; Tchórzewski, Marek; Janczarek, Monika

    2016-01-01

    Rhizobium leguminosarum bv. trifolii is capable of establishing a symbiotic relationship with plants from the genus Trifolium. Previously, a regulatory protein encoded by rosR was identified and characterized in this bacterium. RosR possesses a Cys2-His2-type zinc finger motif and belongs to Ros/MucR family of rhizobial transcriptional regulators. Transcriptome profiling of the rosR mutant revealed a role of this protein in several cellular processes, including the synthesis of cell-surface components and polysaccharides, motility, and bacterial metabolism. Here, we show that a mutation in rosR resulted in considerable changes in R. leguminosarum bv. trifolii protein profiles. Extracellular, membrane, and periplasmic protein profiles of R. leguminosarum bv. trifolii wild type and the rosR mutant were examined, and proteins with substantially different abundances between these strains were identified. Compared with the wild type, extracellular fraction of the rosR mutant contained greater amounts of several proteins, including Ca2+-binding cadherin-like proteins, a RTX-like protein, autoaggregation protein RapA1, and flagellins FlaA and FlaB. In contrast, several proteins involved in the uptake of various substrates were less abundant in the mutant strain (DppA, BraC, and SfuA). In addition, differences were observed in membrane proteins of the mutant and wild-type strains, which mainly concerned various transport system components. Using atomic force microscopy (AFM) imaging, we characterized the topography and surface properties of the rosR mutant and wild-type cells. We found that the mutation in rosR gene also affected surface properties of R. leguminosarum bv. trifolii. The mutant cells were significantly more hydrophobic than the wild-type cells, and their outer membrane was three times more permeable to the hydrophobic dye N-phenyl-1-naphthylamine. The mutation of rosR also caused defects in bacterial symbiotic interaction with clover plants. Compared with

  9. The Regulatory Protein RosR Affects Rhizobium leguminosarum bv. trifolii Protein Profiles, Cell Surface Properties, and Symbiosis with Clover.

    PubMed

    Rachwał, Kamila; Boguszewska, Aleksandra; Kopcińska, Joanna; Karaś, Magdalena; Tchórzewski, Marek; Janczarek, Monika

    2016-01-01

    Rhizobium leguminosarum bv. trifolii is capable of establishing a symbiotic relationship with plants from the genus Trifolium. Previously, a regulatory protein encoded by rosR was identified and characterized in this bacterium. RosR possesses a Cys2-His2-type zinc finger motif and belongs to Ros/MucR family of rhizobial transcriptional regulators. Transcriptome profiling of the rosR mutant revealed a role of this protein in several cellular processes, including the synthesis of cell-surface components and polysaccharides, motility, and bacterial metabolism. Here, we show that a mutation in rosR resulted in considerable changes in R. leguminosarum bv. trifolii protein profiles. Extracellular, membrane, and periplasmic protein profiles of R. leguminosarum bv. trifolii wild type and the rosR mutant were examined, and proteins with substantially different abundances between these strains were identified. Compared with the wild type, extracellular fraction of the rosR mutant contained greater amounts of several proteins, including Ca(2+)-binding cadherin-like proteins, a RTX-like protein, autoaggregation protein RapA1, and flagellins FlaA and FlaB. In contrast, several proteins involved in the uptake of various substrates were less abundant in the mutant strain (DppA, BraC, and SfuA). In addition, differences were observed in membrane proteins of the mutant and wild-type strains, which mainly concerned various transport system components. Using atomic force microscopy (AFM) imaging, we characterized the topography and surface properties of the rosR mutant and wild-type cells. We found that the mutation in rosR gene also affected surface properties of R. leguminosarum bv. trifolii. The mutant cells were significantly more hydrophobic than the wild-type cells, and their outer membrane was three times more permeable to the hydrophobic dye N-phenyl-1-naphthylamine. The mutation of rosR also caused defects in bacterial symbiotic interaction with clover plants. Compared with

  10. The Regulatory Protein RosR Affects Rhizobium leguminosarum bv. trifolii Protein Profiles, Cell Surface Properties, and Symbiosis with Clover

    PubMed Central

    Rachwał, Kamila; Boguszewska, Aleksandra; Kopcińska, Joanna; Karaś, Magdalena; Tchórzewski, Marek; Janczarek, Monika

    2016-01-01

    Rhizobium leguminosarum bv. trifolii is capable of establishing a symbiotic relationship with plants from the genus Trifolium. Previously, a regulatory protein encoded by rosR was identified and characterized in this bacterium. RosR possesses a Cys2-His2-type zinc finger motif and belongs to Ros/MucR family of rhizobial transcriptional regulators. Transcriptome profiling of the rosR mutant revealed a role of this protein in several cellular processes, including the synthesis of cell-surface components and polysaccharides, motility, and bacterial metabolism. Here, we show that a mutation in rosR resulted in considerable changes in R. leguminosarum bv. trifolii protein profiles. Extracellular, membrane, and periplasmic protein profiles of R. leguminosarum bv. trifolii wild type and the rosR mutant were examined, and proteins with substantially different abundances between these strains were identified. Compared with the wild type, extracellular fraction of the rosR mutant contained greater amounts of several proteins, including Ca2+-binding cadherin-like proteins, a RTX-like protein, autoaggregation protein RapA1, and flagellins FlaA and FlaB. In contrast, several proteins involved in the uptake of various substrates were less abundant in the mutant strain (DppA, BraC, and SfuA). In addition, differences were observed in membrane proteins of the mutant and wild-type strains, which mainly concerned various transport system components. Using atomic force microscopy (AFM) imaging, we characterized the topography and surface properties of the rosR mutant and wild-type cells. We found that the mutation in rosR gene also affected surface properties of R. leguminosarum bv. trifolii. The mutant cells were significantly more hydrophobic than the wild-type cells, and their outer membrane was three times more permeable to the hydrophobic dye N-phenyl-1-naphthylamine. The mutation of rosR also caused defects in bacterial symbiotic interaction with clover plants. Compared with

  11. 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…

  12. Effect of corn silage hybrid and metabolizable protein supply on nitrogen metabolism of lactating dairy cows.

    PubMed

    Weiss, W P; Wyatt, D J

    2006-05-01

    This experiment was conducted to determine the effects of corn silage hybrid and supply of metabolizable protein (MP) on manure excretion and N metabolism by lactating dairy cows. Eight Holstein cows in midlactation (replicated 4 x 4 Latin square with 21-d periods) were fed 1 of 4 treatments, arranged factorially. Diets contained 55% corn silage made from a dual-purpose hybrid or a brown midrib (BMR) hybrid, and 45% concentrate that contained either a low or high concentration of rumen undegradable protein (altered by the addition of fish meal and treated soybean meal). Crude protein averaged 14.0 and 17.5% and supply of MP averaged 2,360 and 2,990 g/d for the low and high MP treatments (not affected by hybrid). Increasing supply of MP greatly increased urine output and tended to increase total manure output, whereas diets with BMR silage tended to reduce manure output. Increased MP supply increased daily excretion of manure N by 25% (465 vs. 374 g/d), fecal N by 27 g, and urinary N by 64 g. When the effect of N intake was removed, cows fed BMR silage excreted about 15 g/d less N via manure than cows fed the other silage. Rumen ammonia, volatile fatty acid concentrations, and pH were not affected by treatment. Dry matter intake (overall mean = 24.9 kg/d) tended to be increased with increased MP but was not affected by hybrid. Milk production for cows fed BMR was higher than for cows fed the dual-purpose hybrid (36.9 vs. 35.3 kg/d), but because of changes in fat concentration, yield of energy-corrected milk was not affected by treatment. The only interaction observed was increased yield of milk protein when BMR silage was combined with increased supply of MP.

  13. Protein metabolism in slow- and fast-twitch skeletal muscle during turpentine-induced inflammation

    PubMed Central

    Muthny, Tomas; Kovarik, Miroslav; Sispera, Ludek; Tilser, Ivan; Holecek, Milan

    2008-01-01

    The aim of our study was to evaluate the differences in protein and amino acid metabolism after subcutaneous turpentine administration in the soleus muscle (SOL), predominantly composed of red fibres, and the extensor digitorum longus muscle (EDL) composed of white fibres. Young rats (40–60 g) were injected subcutaneously with 0.2 ml of turpentine oil/100 g body weight (inflammation) or with the same volume of saline solution (control). Twenty-four hours later SOL and EDL were dissected and incubated in modified Krebs–Heinseleit buffer to estimate total and myofibrillar proteolysis, chymotrypsin-like activity of proteasome (CHTLA), leucine oxidation, protein synthesis and amino acid release into the medium. The data obtained demonstrate that in intact rats, all parameters measured except protein synthesis are significantly higher in SOL than in EDL. In turpentine treated animals, CHTLA increased and protein synthesis decreased significantly more in EDL. Release of leucine was inhibited significantly more in SOL. We conclude that turpentine-induced inflammation affects more CHTLA, protein synthesis and leucine release in EDL compared to SOL. PMID:18197871

  14. Plant Protein and Animal Proteins: Do They Differentially Affect Cardiovascular Disease Risk?12

    PubMed Central

    Richter, Chesney K; Skulas-Ray, Ann C; Champagne, Catherine M; Kris-Etherton, Penny M

    2015-01-01

    Proteins from plant-based compared with animal-based food sources may have different effects on cardiovascular disease (CVD) risk factors. Numerous epidemiologic and intervention studies have evaluated their respective health benefits; however, it is difficult to isolate the role of plant or animal protein on CVD risk. This review evaluates the current evidence from observational and intervention studies, focusing on the specific protein-providing foods and populations studied. Dietary protein is derived from many food sources, and each provides a different composite of nonprotein compounds that can also affect CVD risk factors. Increasing the consumption of protein-rich foods also typically results in lower intakes of other nutrients, which may simultaneously influence outcomes. Given these complexities, blanket statements about plant or animal protein may be too general, and greater consideration of the specific protein food sources and the background diet is required. The potential mechanisms responsible for any specific effects of plant and animal protein are similarly multifaceted and include the amino acid content of particular foods, contributions from other nonprotein compounds provided concomitantly by the whole food, and interactions with the gut microbiome. Evidence to date is inconclusive, and additional studies are needed to further advance our understanding of the complexity of plant protein vs. animal protein comparisons. Nonetheless, current evidence supports the idea that CVD risk can be reduced by a dietary pattern that provides more plant sources of protein compared with the typical American diet and also includes animal-based protein foods that are unprocessed and low in saturated fat. PMID:26567196

  15. Plant protein and animal proteins: do they differentially affect cardiovascular disease risk?

    PubMed

    Richter, Chesney K; Skulas-Ray, Ann C; Champagne, Catherine M; Kris-Etherton, Penny M

    2015-11-01

    Proteins from plant-based compared with animal-based food sources may have different effects on cardiovascular disease (CVD) risk factors. Numerous epidemiologic and intervention studies have evaluated their respective health benefits; however, it is difficult to isolate the role of plant or animal protein on CVD risk. This review evaluates the current evidence from observational and intervention studies, focusing on the specific protein-providing foods and populations studied. Dietary protein is derived from many food sources, and each provides a different composite of nonprotein compounds that can also affect CVD risk factors. Increasing the consumption of protein-rich foods also typically results in lower intakes of other nutrients, which may simultaneously influence outcomes. Given these complexities, blanket statements about plant or animal protein may be too general, and greater consideration of the specific protein food sources and the background diet is required. The potential mechanisms responsible for any specific effects of plant and animal protein are similarly multifaceted and include the amino acid content of particular foods, contributions from other nonprotein compounds provided concomitantly by the whole food, and interactions with the gut microbiome. Evidence to date is inconclusive, and additional studies are needed to further advance our understanding of the complexity of plant protein vs. animal protein comparisons. Nonetheless, current evidence supports the idea that CVD risk can be reduced by a dietary pattern that provides more plant sources of protein compared with the typical American diet and also includes animal-based protein foods that are unprocessed and low in saturated fat.

  16. Soy protein isolate does not affect ellagitannin bioavailability and urolithin formation when mixed with pomegranate juice in humans.

    PubMed

    Yang, Jieping; Lee, Rupo; Henning, Susanne M; Thames, Gail; Hsu, Mark; ManLam, Hei; Heber, David; Li, Zhaoping

    2016-03-01

    We investigated the effect of mixing soy protein isolate and pomegranate juice (PJ) on the bioavailability and metabolism of ellagitannins (ETs) in healthy volunteers. Eighteen healthy volunteers consumed PJ alone or PJ premixed with soy protein isolate (PJSP). The concentration of plasma ellagic acid (EA) and urine urolithins was measured. There was no significant difference in plasma EA over a 6-h period between the two interventions. While the maximum concentration of plasma EA after PJSP consumption was slightly but significantly lower than after PJ consumption, EA remained in the plasma longer with an elimination half-life t1/2E at 1.36±0.59 versus 1.06±0.47h for PJSP and PJ consumption, respectively. Urinary urolithin A, B and C was not significantly different between the two interventions. In conclusion, premixing soy protein isolate and PJ did not affect the bioavailability or the metabolism of pomegranate ETs in healthy volunteers.

  17. Retrospective surveillance of metabolic parameters affecting reproductive performance of Japanese Black breeding cows

    PubMed Central

    Watanabe, Urara; Yamato, Osamu; Otoi, Takeshige; Okamoto, Koji

    2014-01-01

    This retrospective study was conducted to confirm the relationship between pre- and postpartum metabolic parameters and postpartum reproductive performance and to clarify seasonal characteristics of the metabolic parameters by using our metabolic profile test (MPT) database of Japanese Black breeding herds. In evaluation 1, MPT databases of blood samples from multiparous cows collected prepartum and postpartum were divided into two groups according to calving interval, and each MPT parameter was compared. In evaluation 2, the same MPT databases used in evaluation 1 were divided into two groups according to the sampling period. Significant differences were found in the prepartal total protein and postpartal γ-glutamyltransferase in evaluation 1. In evaluation 2, significant differences were found in the prepartal and postpartal total protein, albumin/globulin ratio, and glucose. Clear seasonal differences in MPT results emphasized the usefulness of the MPT in breeding cattle herds fed home-pasture roughage and suggest that unsatisfactory reproductive performance during hot periods reflects inadequate nutritional content of the diet and possible reduced feed intake due to heat stress. PMID:24675835

  18. Insulin sensitivity of muscle protein metabolism is altered in patients with chronic kidney disease and metabolic acidosis

    PubMed Central

    Garibotto, Giacomo; Sofia, Antonella; Russo, Rodolfo; Paoletti, Ernesto; Bonanni, Alice; Parodi, Emanuele L; Viazzi, Francesca; Verzola, Daniela

    2015-01-01

    An emergent hypothesis is that a resistance to the anabolic drive by insulin may contribute to loss of strength and muscle mass in patients with chronic kidney disease (CKD). We tested whether insulin resistance extends to protein metabolism using the forearm perfusion method with arterial insulin infusion in 7 patients with CKD and metabolic acidosis (bicarbonate 19 mmol/l) and 7 control individuals. Forearm glucose balance and protein turnover (2H-phenylalanine kinetics) were measured basally and in response to insulin infused at different rates for 2 h to increase local forearm plasma insulin concentration by approximately 20 and 50 μU/ml. In response to insulin, forearm glucose uptake was significantly increased to a lesser extent (−40%) in patients with CKD than controls. In addition, whereas in the controls net muscle protein balance and protein degradation were decreased by both insulin infusion rates, in patients with CKD net protein balance and protein degradation were sensitive to the high (0.035 mU/kg per min) but not the low (0.01 mU/kg per min) insulin infusion. Besides blunting muscle glucose uptake, CKD and acidosis interfere with the normal suppression of protein degradation in response to a moderate rise in plasma insulin. Thus, alteration of protein metabolism by insulin may lead to changes in body tissue composition which may become clinically evident in conditions characterized by low insulinemia. PMID:26308671

  19. Patterns of indirect protein interactions suggest a spatial organization to metabolism.

    PubMed

    Pérez-Bercoff, Åsa; McLysaght, Aoife; Conant, Gavin C

    2011-11-01

    It has long been believed that cells organize their cytoplasm so as to efficiently channel metabolites between sequential enzymes. This metabolic channeling has the potential to yield higher metabolic fluxes as well as better regulatory control over metabolism. One mechanism for achieving such channeling is to ensure that sequential enzymes in a pathway are physically close to each other in the cell. We present evidence that indirect protein interactions between related enzymes represent a global mechanism for achieving metabolic channeling; the intuition being that protein interactions between enzymes and non-enzymatic mediator proteins are a powerful means of physically associating enzymes in a modular fashion. By analyzing the metabolic and protein-protein interactions networks of Escherichia coli, yeast and humans, we are able to show that all three species have many more indirect protein interactions linking enzymes that share metabolites than would be expected by chance. Moreover, these interactions are distributed non-randomly in the metabolic network. Our analyses in yeast and E. coli show that reactions possessing such interactions also show higher flux than do those lacking them. On the basis of these observations, we suggest that an important role of protein interactions with mediator proteins is to contribute to the spatial organization of the cell. This hypothesis is supported by the fact that these mediator proteins are also enriched with annotations related to signal transduction, a system where scaffolding proteins are known to limit cross-talk by controlling spatial localization.

  20. Metabolic syndrome and C-reactive protein in bank employees

    PubMed Central

    Cattafesta, Monica; Bissoli, Nazaré Souza; Salaroli, Luciane Bresciani

    2016-01-01

    Background The ultrasensitive C-reactive protein (us-CRP) is used for the diagnosis of cardiovascular disease, but it is not well described as a marker for the diagnosis of metabolic syndrome (MS). Methods An observational and transversal study of bank employees evaluated anthropometric, hemodynamic, and biochemical data. CRP values were determined using commercial kits from Roche Diagnostics Ltd, and MS criteria were analyzed according to National Cholesterol Education Program’s – Adult Treatment Panel III (NCEP/ATP III). Results A total of 88 individuals had MS, and 77.3% (n=68) of these showed alterations of us-CRP (P=0.0001, confidence interval [CI] 0.11–0.34). Individuals with MS had higher mean values of us-CRP in global measures (P=0.0001) and stratified by sex (P=0.004) than individuals without the syndrome. This marker exhibited significant differences with varying criteria for MS, such as waist circumference (P=0.0001), triglycerides (P=0.002), and diastolic blood pressure (P=0.007), and the highest levels of us-CRP were found in individuals with more MS criteria. Conclusion us-CRP was strongly associated with the presence of MS and MS criteria in this group of workers. us-CRP is a useful and effective marker for identifying the development of MS and may be used as a reference in routine care. PMID:27274294

  1. Starch Granule Re-Structuring by Starch Branching Enzyme and Glucan Water Dikinase Modulation Affects Caryopsis Physiology and Metabolism.

    PubMed

    Shaik, Shahnoor S; Obata, Toshihiro; Hebelstrup, Kim H; Schwahn, Kevin; Fernie, Alisdair R; Mateiu, Ramona V; Blennow, Andreas

    2016-01-01

    Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed relatively little effect, AO showed significant reduction in starch accumulation with re-direction to protein and β-glucan (BG) accumulation. Metabolite profiling indicated significantly higher sugar accumulation in AO, with re-partitioning of carbon to accumulate amino acids, and interestingly it also had high levels of some important stress-related metabolites and potentially protective metabolites, possibly to elude deleterious effects. Investigations on starch molecular structure revealed significant increase in starch phosphate and amylose content in HP and AO respectively with obvious differences in starch granule morphology at maturity. The results demonstrate that decreasing the storage starch branching resulted in metabolic adjustments and re-directions, tuning to evade deleterious effects on caryopsis physiology and plant performance while only little effect was evident by increasing starch-bound phosphate as a result of overexpressing GWD.

  2. Starch Granule Re-Structuring by Starch Branching Enzyme and Glucan Water Dikinase Modulation Affects Caryopsis Physiology and Metabolism.

    PubMed

    Shaik, Shahnoor S; Obata, Toshihiro; Hebelstrup, Kim H; Schwahn, Kevin; Fernie, Alisdair R; Mateiu, Ramona V; Blennow, Andreas

    2016-01-01

    Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed relatively little effect, AO showed significant reduction in starch accumulation with re-direction to protein and β-glucan (BG) accumulation. Metabolite profiling indicated significantly higher sugar accumulation in AO, with re-partitioning of carbon to accumulate amino acids, and interestingly it also had high levels of some important stress-related metabolites and potentially protective metabolites, possibly to elude deleterious effects. Investigations on starch molecular structure revealed significant increase in starch phosphate and amylose content in HP and AO respectively with obvious differences in starch granule morphology at maturity. The results demonstrate that decreasing the storage starch branching resulted in metabolic adjustments and re-directions, tuning to evade deleterious effects on caryopsis physiology and plant performance while only little effect was evident by increasing starch-bound phosphate as a result of overexpressing GWD. PMID:26891365

  3. Starch Granule Re-Structuring by Starch Branching Enzyme and Glucan Water Dikinase Modulation Affects Caryopsis Physiology and Metabolism

    PubMed Central

    Shaik, Shahnoor S.; Obata, Toshihiro; Hebelstrup, Kim H.; Schwahn, Kevin; Fernie, Alisdair R.; Mateiu, Ramona V.; Blennow, Andreas

    2016-01-01

    Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed relatively little effect, AO showed significant reduction in starch accumulation with re-direction to protein and β-glucan (BG) accumulation. Metabolite profiling indicated significantly higher sugar accumulation in AO, with re-partitioning of carbon to accumulate amino acids, and interestingly it also had high levels of some important stress-related metabolites and potentially protective metabolites, possibly to elude deleterious effects. Investigations on starch molecular structure revealed significant increase in starch phosphate and amylose content in HP and AO respectively with obvious differences in starch granule morphology at maturity. The results demonstrate that decreasing the storage starch branching resulted in metabolic adjustments and re-directions, tuning to evade deleterious effects on caryopsis physiology and plant performance while only little effect was evident by increasing starch-bound phosphate as a result of overexpressing GWD. PMID:26891365

  4. Cell differentiation within a yeast colony: metabolic and regulatory parallels with a tumor-affected organism.

    PubMed

    Cáp, Michal; Stěpánek, Luděk; Harant, Karel; Váchová, Libuše; Palková, Zdena

    2012-05-25

    Nutrient sensing and metabolic reprogramming are crucial for metazoan cell aging and tumor growth. Here, we identify metabolic and regulatory parallels between a layered, multicellular yeast colony and a tumor-affected organism. During development, a yeast colony stratifies into U and L cells occupying the upper and lower colony regions, respectively. U cells activate a unique metabolism controlled by the glutamine-induced TOR pathway, amino acid-sensing systems (SPS and Gcn4p) and signaling from mitochondria with lowered respiration. These systems jointly modulate U cell physiology, which adapts to nutrient limitations and utilize the nutrients released from L cells. Stress-resistant U cells share metabolic pathways and other similar characteristics with tumor cells, including the ability to proliferate. L cells behave similarly to stressed and starving cells, which activate degradative mechanisms to provide nutrients to U cells. Our data suggest a nutrient flow between both cell types, resembling the Cori cycle and glutamine-NH(4)(+) shuttle between tumor and healthy metazoan cells.

  5. Assessing the Metabolic Diversity of Streptococcus from a Protein Domain Point of View

    PubMed Central

    Koehorst, Jasper J.; Martins dos Santos, Vitor A. P.; Schaap, Peter J.

    2015-01-01

    Understanding the diversity and robustness of the metabolism of bacteria is fundamental for understanding how bacteria evolve and adapt to different environments. In this study, we characterised 121 Streptococcus strains and studied metabolic diversity from a protein domain perspective. Metabolic pathways were described in terms of the promiscuity of domains participating in metabolic pathways that were inferred to be functional. Promiscuity was defined by adapting existing measures based on domain abundance and versatility. The approach proved to be successful in capturing bacterial metabolic flexibility and species diversity, indicating that it can be described in terms of reuse and sharing functional domains in different proteins involved in metabolic activity. Additionally, we showed striking differences among metabolic organisation of the pathogenic serotype 2 Streptococcus suis and other strains. PMID:26366735

  6. 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

  7. 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.

  8. A High Protein Diet during Pregnancy Affects Hepatic Gene Expression of Energy Sensing Pathways along Ontogenesis in a Porcine Model

    PubMed Central

    Oster, Michael; Murani, Eduard; Metges, Cornelia C.; Ponsuksili, Siriluck; Wimmers, Klaus

    2011-01-01

    In rodent models and in humans the impact of gestational diets on the offspring's phenotype was shown experimentally and epidemiologically. The underlying programming of fetal development was shown to be associated with an increased risk of degenerative diseases in adulthood, including the metabolic syndrome. There are clues that diet-dependent modifications of the metabolism during fetal life can persist until adulthood. This leads to the hypothesis that the offspring's transcriptomes show short-term and long-term changes depending on the maternal diet. To this end pregnant German landrace gilts were fed either a high protein diet (HP, 30% CP) or an adequate protein diet (AP, 12% CP) throughout pregnancy. Hepatic transcriptome profiles of the offspring were analyzed at prenatal (94 dpc) and postnatal stages (1, 28, 188 dpn). Depending on the gestational dietary exposure, mRNA expression levels of genes related to energy metabolism, N-metabolism, growth factor signaling pathways, lipid metabolism, nucleic acid metabolism and stress/immune response were affected either in a short-term or in a long-term manner. Gene expression profiles at fetal stage 94 dpc were almost unchanged between the diets. The gestational HP diet affected the hepatic expression profiles at prenatal and postnatal stages. The effects encompassed a modulation of the genome in terms of an altered responsiveness of energy and nutrient sensing pathways. Differential expression of genes related to energy production and nutrient utilization contribute to the maintenance of development and growth performance within physiological norms, however the modulation of these pathways may be accompanied by a predisposition for metabolic disturbances up to adult stages. PMID:21789176

  9. The unfolded protein response affects readthrough of premature termination codons

    PubMed Central

    Oren, Yifat S; McClure, Michelle L; Rowe, Steven M; Sorscher, Eric J; Bester, Assaf C; Manor, Miriam; Kerem, Eitan; Rivlin, Joseph; Zahdeh, Fouad; Mann, Matthias; Geiger, Tamar; Kerem, Batsheva

    2014-01-01

    One-third of monogenic inherited diseases result from premature termination codons (PTCs). Readthrough of in-frame PTCs enables synthesis of full-length functional proteins. However, extended variability in the response to readthrough treatment is found among patients, which correlates with the level of nonsense transcripts. Here, we aimed to reveal cellular pathways affecting this inter-patient variability. We show that activation of the unfolded protein response (UPR) governs the response to readthrough treatment by regulating the levels of transcripts carrying PTCs. Quantitative proteomic analyses showed substantial differences in UPR activation between patients carrying PTCs, correlating with their response. We further found a significant inverse correlation between the UPR and nonsense-mediated mRNA decay (NMD), suggesting a feedback loop between these homeostatic pathways. We uncovered and characterized the mechanism underlying this NMD-UPR feedback loop, which augments both UPR activation and NMD attenuation. Importantly, this feedback loop enhances the response to readthrough treatment, highlighting its clinical importance. Altogether, our study demonstrates the importance of the UPR and its regulatory network for genetic diseases caused by PTCs and for cell homeostasis under normal conditions. PMID:24705877

  10. Do Non-Collagenous Proteins Affect Skeletal Mechanical Properties?

    PubMed Central

    Morgan, Stacyann; Poundarik, Atharva A.; Vashishth, Deepak

    2015-01-01

    The remarkable mechanical behavior of bone is attributed to its complex nanocomposite structure that, in addition to mineral and collagen, comprises a variety of non-collagenous matrix proteins or NCPs. Traditionally, NCPs have been studied as signaling molecules in biological processes including bone formation, resorption and turnover. Limited attention has been given to their role in determining the mechanical properties of bone. Recent studies have highlighted that NCPs can indeed be lost or modified with aging, diseases and drug therapies. Homozygous and heterozygous mice models of key NCP provide a useful approach to determine the impact of NCPs on bone morphology as well as matrix quality, and to carry out detailed mechanical analysis for elucidating the pathway by which NCPs can affect the mechanical properties of bone. In this article, we present a systematic analysis of a large cohort of NCPs on bone’s structural and material hierarchy, and identify three principal pathways by which they determine bone’s mechanical properties. These pathways include alterations of bone morphological parameters crucial for bone’s structural competency, bone quality changes in key matrix parameters (mineral and collagen), and a direct role as load bearing structural proteins. PMID:26048282

  11. Cooked sausage batter cohesiveness as affected by sarcoplasmic proteins.

    PubMed

    Farouk, M M; Wieliczko, K; Lim, R; Turnwald, S; Macdonald, G A

    2002-05-01

    In the first trial, m. semitendinosus and m. biceps femoris were held at 0, 10 and 35 °C until they entered rigor, and in the second trial, minced m. semitendinosus was washed in water for 15, 30, 45 or 60 min. The samples from both the trials were then used to make a finely comminuted sausage batter. Soluble sarcoplasmic protein (SSP) levels decreased with increasing rigor temperature (P < 0.05) or washing (P < 0.01). Cooked batter shear stress was not affected by SSP level, but batter shear strain decreased with the decreasing SSP level associated with an increasing rigor temperature (P < 0.05) or washing (P < 0.01). Reducing the SSP content lowered the cook yield (P < 0.05) and emulsion stability (P < 0.01) of the batter from the washed samples compared to that of controls. The results suggest that sarcoplasmic proteins are important in determining the strain values (cohesiveness) of cooked sausage batter.

  12. Do Non-collagenous Proteins Affect Skeletal Mechanical Properties?

    PubMed

    Morgan, Stacyann; Poundarik, Atharva A; Vashishth, Deepak

    2015-09-01

    The remarkable mechanical behavior of bone is attributed to its complex nanocomposite structure that, in addition to mineral and collagen, comprises a variety of non-collagenous matrix proteins or NCPs. Traditionally, NCPs have been studied as signaling molecules in biological processes including bone formation, resorption, and turnover. Limited attention has been given to their role in determining the mechanical properties of bone. Recent studies have highlighted that NCPs can indeed be lost or modified with aging, diseases, and drug therapies. Homozygous and heterozygous mice models of key NCP provide a useful approach to determine the impact of NCPs on bone morphology as well as matrix quality, and to carry out detailed mechanical analysis for elucidating the pathway by which NCPs can affect the mechanical properties of bone. In this article, we present a systematic analysis of a large cohort of NCPs on bone's structural and material hierarchy, and identify three principal pathways by which they determine bone's mechanical properties. These pathways include alterations of bone morphological parameters crucial for bone's structural competency, bone quality changes in key matrix parameters (mineral and collagen), and a direct role as load-bearing structural proteins.

  13. Lengths of Orthologous Prokaryotic Proteins Are Affected by Evolutionary Factors

    PubMed Central

    Tatarinova, Tatiana; Dien Bard, Jennifer; Cohen, Irit

    2015-01-01

    Proteins of the same functional family (for example, kinases) may have significantly different lengths. It is an open question whether such variation in length is random or it appears as a response to some unknown evolutionary driving factors. The main purpose of this paper is to demonstrate existence of factors affecting prokaryotic gene lengths. We believe that the ranking of genomes according to lengths of their genes, followed by the calculation of coefficients of association between genome rank and genome property, is a reasonable approach in revealing such evolutionary driving factors. As we demonstrated earlier, our chosen approach, Bubble-sort, combines stability, accuracy, and computational efficiency as compared to other ranking methods. Application of Bubble Sort to the set of 1390 prokaryotic genomes confirmed that genes of Archaeal species are generally shorter than Bacterial ones. We observed that gene lengths are affected by various factors: within each domain, different phyla have preferences for short or long genes; thermophiles tend to have shorter genes than the soil-dwellers; halophiles tend to have longer genes. We also found that species with overrepresentation of cytosines and guanines in the third position of the codon (GC3 content) tend to have longer genes than species with low GC3 content. PMID:26114113

  14. Lipoic acid entrains the hepatic circadian clock and lipid metabolic proteins that have been desynchronized with advanced age.

    PubMed

    Keith, Dove; Finlay, Liam; Butler, Judy; Gómez, Luis; Smith, Eric; Moreau, Régis; Hagen, Tory

    2014-07-18

    It is well established that lipid metabolism is controlled, in part, by circadian clocks. However, circadian clocks lose temporal precision with age and correlates with elevated incidence in dyslipidemia and metabolic syndrome in older adults. Because our lab has shown that lipoic acid (LA) improves lipid homeostasis in aged animals, we hypothesized that LA affects the circadian clock to achieve these results. We fed 24 month old male F344 rats a diet supplemented with 0.2% (w/w) LA for 2 weeks prior to sacrifice and quantified hepatic circadian clock protein levels and clock-controlled lipid metabolic enzymes. LA treatment caused a significant phase-shift in the expression patterns of the circadian clock proteins Period (Per) 2, Brain and Muscle Arnt-Like1 (BMAL1), and Reverse Erythroblastosis virus (Rev-erb) β without altering the amplitude of protein levels during the light phase of the day. LA also significantly altered the oscillatory patterns of clock-controlled proteins associated with lipid metabolism. The level of peroxisome proliferator-activated receptor (PPAR) α was significantly increased and acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) were both significantly reduced, suggesting that the LA-supplemented aged animals are in a catabolic state. We conclude that LA remediates some of the dyslipidemic processes associated with advanced age, and this mechanism may be at least partially through entrainment of circadian clocks. PMID:24944020

  15. Effects of Radiation and Dietary Iron on Expression of Genes and Proteins Involved in Drug Metabolism

    NASA Technical Reports Server (NTRS)

    Faust, K. M.; Wotring, V. E.

    2014-01-01

    .5. RESULTS Among the redox homeostasis genes examined, metallothionein showed a significant down regulation in the radiation treated group (-3.85 fold) and a trend toward down regulation in the high Fe + rad group. Metallothionein is involved in the regulation of physiological metals and also has antioxidant activities. Among the drug metabolism genes examined, ATP binding cassette subfamily B (Abcb1b) gene expression increased more than 10-fold in both groups that received radiation treatments. This increased expression was also seen at the protein level. This ABC transporter carries many different compounds across cell membranes, including administered medications. The cytochrome P450 2E1 enzyme, a mixed-function oxidase that deactivates some medications and activates others, showed about a 2-fold increase in gene expression in both radiation-treated groups, with a trend toward increased expression at the protein level. Expression of epoxide hydrolase, which detoxifies polycyclic aromatic hydrocarbons, showed similar 2-fold increases. Among the DNA repair genes examined, expression of RAD51 was significantly down regulated (1.5 fold) in the radiation treated group. RAD51 is involved in repair of double-stranded DNA breaks. CONCLUSION This experiment used 2 different sources of physiological oxidative stress, administered separately and together, and examined their impacts on liver gene and protein expression. It is clear that significant changes occurred in expression of several genes and proteins in the radiation-treated animals. If the results from this ground analog of portions of the spaceflight environment hold true for the spaceflight environment itself, the physiological roles of the affected enzymes (drug transport and metabolism, redox homeostasis) could mean consequences in redox homeostasis or the pharmacokinetics of administered medications

  16. 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

  17. Deiodinase Knockdown during Early Zebrafish Development Affects Growth, Development, Energy Metabolism, Motility and Phototransduction

    PubMed Central

    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

  18. Metabolic Enzymes Enjoying New Partnerships as RNA-Binding Proteins.

    PubMed

    Castello, Alfredo; Hentze, Matthias W; Preiss, Thomas

    2015-12-01

    In the past century, few areas of biology advanced as much as our understanding of the pathways of intermediary metabolism. Initially considered unimportant in terms of gene regulation, crucial cellular fate changes, cell differentiation, or malignant transformation are now known to involve 'metabolic remodeling' with profound changes in the expression of many metabolic enzyme genes. This review focuses on the recent identification of RNA-binding activity of numerous metabolic enzymes. We discuss possible roles of this unexpected second activity in feedback gene regulation ('moonlighting') and/or in the control of enzymatic function. We also consider how metabolism-driven post-translational modifications could regulate enzyme-RNA interactions. Thus, RNA emerges as a new partner of metabolic enzymes with far-reaching possible consequences to be unraveled in the future.

  19. Metabolic Enzymes Enjoying New Partnerships as RNA-Binding Proteins

    PubMed Central

    Castello, Alfredo; Hentze, Matthias W.; Preiss, Thomas

    2015-01-01

    In the past century, few areas of biology advanced as much as our understanding of the pathways of intermediary metabolism. Initially considered unimportant in terms of gene regulation, crucial cellular fate changes, cell differentiation, or malignant transformation are now known to involve ‘metabolic remodeling’ with profound changes in the expression of many metabolic enzyme genes. This review focuses on the recent identification of RNA-binding activity of numerous metabolic enzymes. We discuss possible roles of this unexpected second activity in feedback gene regulation (‘moonlighting’) and/or in the control of enzymatic function. We also consider how metabolism-driven post-translational modifications could regulate enzyme–RNA interactions. Thus, RNA emerges as a new partner of metabolic enzymes with far-reaching possible consequences to be unraveled in the future. PMID:26520658

  20. Gestational diabetes mellitus epigenetically affects genes predominantly involved in metabolic diseases

    PubMed Central

    Ruchat, Stephanie-May; Houde, Andrée-Anne; Voisin, Grégory; St-Pierre, Julie; Perron, Patrice; Baillargeon, Jean-Patrice; Gaudet, Daniel; Hivert, Marie-France; Brisson, Diane; Bouchard, Luigi

    2013-01-01

    Offspring exposed to gestational diabetes mellitus (GDM) have an increased risk for chronic diseases, and one promising mechanism for fetal metabolic programming is epigenetics. Therefore, we postulated that GDM exposure impacts the offspring’s methylome and used an epigenomic approach to explore this hypothesis. Placenta and cord blood samples were obtained from 44 newborns, including 30 exposed to GDM. Women were recruited at first trimester of pregnancy and followed until delivery. GDM was assessed after a 75-g oral glucose tolerance test at 24–28 weeks of pregnancy. DNA methylation was measured at > 485,000 CpG sites (Infinium HumanMethylation450 BeadChips). Ingenuity Pathway Analysis was conducted to identify metabolic pathways epigenetically affected by GDM. Our results showed that 3,271 and 3,758 genes in placenta and cord blood, respectively, were potentially differentially methylated between samples exposed or not to GDM (p-values down to 1 × 10−06; none reached the genome-wide significance levels), with more than 25% (n = 1,029) being common to both tissues. Mean DNA methylation differences between groups were 5.7 ± 3.2% and 3.4 ± 1.9% for placenta and cord blood, respectively. These genes were likely involved in the metabolic diseases pathway (up to 115 genes (11%), p-values for pathways = 1.9 × 10−13 < p < 4.0 × 10−03; including diabetes mellitus p = 4.3 × 10−11). Among the differentially methylated genes, 326 in placenta and 117 in cord blood were also associated with newborn weight. Our results therefore suggest that GDM has epigenetic effects on genes preferentially involved in the metabolic diseases pathway, with consequences on fetal growth and development, and provide supportive evidence that DNA methylation is involved in fetal metabolic programming. PMID:23975224

  1. Metabolic Turnover of Synaptic Proteins: Kinetics, Interdependencies and Implications for Synaptic Maintenance

    PubMed Central

    Cohen, Laurie D.; Zuchman, Rina; Sorokina, Oksana; Müller, Anke; Dieterich, Daniela C.; Armstrong, J. Douglas; Ziv, Tamar; Ziv, Noam E.

    2013-01-01

    Chemical synapses contain multitudes of proteins, which in common with all proteins, have finite lifetimes and therefore need to be continuously replaced. Given the huge numbers of synaptic connections typical neurons form, the demand to maintain the protein contents of these connections might be expected to place considerable metabolic demands on each neuron. Moreover, synaptic proteostasis might differ according to distance from global protein synthesis sites, the availability of distributed protein synthesis facilities, trafficking rates and synaptic protein dynamics. To date, the turnover kinetics of synaptic proteins have not been studied or analyzed systematically, and thus metabolic demands or the aforementioned relationships remain largely unknown. In the current study we used dynamic Stable Isotope Labeling with Amino acids in Cell culture (SILAC), mass spectrometry (MS), Fluorescent Non–Canonical Amino acid Tagging (FUNCAT), quantitative immunohistochemistry and bioinformatics to systematically measure the metabolic half-lives of hundreds of synaptic proteins, examine how these depend on their pre/postsynaptic affiliation or their association with particular molecular complexes, and assess the metabolic load of synaptic proteostasis. We found that nearly all synaptic proteins identified here exhibited half-lifetimes in the range of 2–5 days. Unexpectedly, metabolic turnover rates were not significantly different for presynaptic and postsynaptic proteins, or for proteins for which mRNAs are consistently found in dendrites. Some functionally or structurally related proteins exhibited very similar turnover rates, indicating that their biogenesis and degradation might be coupled, a possibility further supported by bioinformatics-based analyses. The relatively low turnover rates measured here (∼0.7% of synaptic protein content per hour) are in good agreement with imaging-based studies of synaptic protein trafficking, yet indicate that the metabolic load

  2. Protein engineering for metabolic engineering: Current and next-generation tools

    SciTech Connect

    Marcheschi, RJ; Gronenberg, LS; Liao, JC

    2013-04-16

    Protein engineering in the context of metabolic engineering is increasingly important to the field of industrial biotechnology. As the demand for biologically produced food, fuels, chemicals, food additives, and pharmaceuticals continues to grow, the ability to design and modify proteins to accomplish new functions will be required to meet the high productivity demands for the metabolism of engineered organisms. We review advances in selecting, modeling, and engineering proteins to improve or alter their activity. Some of the methods have only recently been developed for general use and are just beginning to find greater application in the metabolic engineering community. We also discuss methods of generating random and targeted diversity in proteins to generate mutant libraries for analysis. Recent uses of these techniques to alter cofactor use; produce non-natural amino acids, alcohols, and carboxylic acids; and alter organism phenotypes are presented and discussed as examples of the successful engineering of proteins for metabolic engineering purposes.

  3. Protein engineering for metabolic engineering: current and next-generation tools

    PubMed Central

    Marcheschi, Ryan J.; Gronenberg, Luisa S.; Liao, James C.

    2014-01-01

    Protein engineering in the context of metabolic engineering is increasingly important to the field of industrial biotechnology. As the demand for biologically-produced food, fuels, chemicals, food additives, and pharmaceuticals continues to grow, the ability to design and modify proteins to accomplish new functions will be required to meet the high productivity demands for the metabolism of engineered organisms. This article reviews advances of selecting, modeling, and engineering proteins to improve or alter their activity. Some of the methods have only recently been developed for general use and are just beginning to find greater application in the metabolic engineering community. We also discuss methods of generating random and targeted diversity in proteins to generate mutant libraries for analysis. Recent uses of these techniques to alter cofactor use, produce non-natural amino acids, alcohols, and carboxylic acids, and alter organism phenotypes are presented and discussed as examples of the successful engineering of proteins for metabolic engineering purposes. PMID:23589443

  4. Deep proteomics of mouse skeletal muscle enables quantitation of protein isoforms, metabolic pathways, and transcription factors.

    PubMed

    Deshmukh, Atul S; Murgia, Marta; Nagaraj, Nagarjuna; Treebak, Jonas T; Cox, Jürgen; Mann, Matthias

    2015-04-01

    Skeletal muscle constitutes 40% of individual body mass and plays vital roles in locomotion and whole-body metabolism. Proteomics of skeletal muscle is challenging because of highly abundant contractile proteins that interfere with detection of regulatory proteins. Using a state-of-the art MS workflow and a strategy to map identifications from the C2C12 cell line model to tissues, we identified a total of 10,218 proteins, including skeletal muscle specific transcription factors like myod1 and myogenin and circadian clock proteins. We obtain absolute abundances for proteins expressed in a muscle cell line and skeletal muscle, which should serve as a valuable resource. Quantitation of protein isoforms of glucose uptake signaling pathways and in glucose and lipid metabolic pathways provides a detailed metabolic map of the cell line compared with tissue. This revealed unexpectedly complex regulation of AMP-activated protein kinase and insulin signaling in muscle tissue at the level of enzyme isoforms.

  5. Deep Proteomics of Mouse Skeletal Muscle Enables Quantitation of Protein Isoforms, Metabolic Pathways, and Transcription Factors*

    PubMed Central

    Deshmukh, Atul S.; Murgia, Marta; Nagaraj, Nagarjuna; Treebak, Jonas T.; Cox, Jürgen; Mann, Matthias

    2015-01-01

    Skeletal muscle constitutes 40% of individual body mass and plays vital roles in locomotion and whole-body metabolism. Proteomics of skeletal muscle is challenging because of highly abundant contractile proteins that interfere with detection of regulatory proteins. Using a state-of-the art MS workflow and a strategy to map identifications from the C2C12 cell line model to tissues, we identified a total of 10,218 proteins, including skeletal muscle specific transcription factors like myod1 and myogenin and circadian clock proteins. We obtain absolute abundances for proteins expressed in a muscle cell line and skeletal muscle, which should serve as a valuable resource. Quantitation of protein isoforms of glucose uptake signaling pathways and in glucose and lipid metabolic pathways provides a detailed metabolic map of the cell line compared with tissue. This revealed unexpectedly complex regulation of AMP-activated protein kinase and insulin signaling in muscle tissue at the level of enzyme isoforms. PMID:25616865

  6. Does hyperketonemia affect protein or glucose kinetics in postabsorptive or traumatized man

    SciTech Connect

    Crowe, P.J.; Royle, G.T.; Wagner, D.; Burke, J.F. )

    1989-10-01

    Leucine and glucose turnover were measured using simultaneous infusions of (13C)leucine and (2H)glucose before and during an infusion of Na DL-hydroxybutyrate (Na DL-HB) in overnight-fasted patients the day before and 3 days after total hip replacement. The ketone body infusion before surgery resulted in a significant increase in plasma leucine concentration and leucine turnover, while glucose concentration and turnover decreased. Surgery increased leucine turnover. Ketone body infusion after surgery caused a further increased leucine turnover while turnover fell as before surgery. We suggest that exogenous ketone bodies decrease hepatic glucose production and probably stimulate a rise in protein synthesis above breakdown leading to a decreased nitrogen excretion as observed by other investigators. Despite the metabolic adaptation to trauma, this response was not affected by surgery.

  7. A computational analysis of protein interactions in metabolic networks reveals novel enzyme pairs potentially involved in metabolic channeling.

    PubMed

    Huthmacher, Carola; Gille, Christoph; Holzhütter, Hermann-Georg

    2008-06-01

    Protein-protein interactions are operative at almost every level of cell structure and function as, for example, formation of sub-cellular organelles, packaging of chromatin, muscle contraction, signal transduction, and regulation of gene expression. Public databases of reported protein-protein interactions comprise hundreds of thousands interactions, and this number is steadily growing. Elucidating the implications of protein-protein interactions for the regulation of the underlying cellular or extra-cellular reaction network remains a great challenge for computational biochemistry. In this work, we have undertaken a systematic and comprehensive computational analysis of reported enzyme-enzyme interactions in the metabolic networks of the model organisms Escherichia coli and Saccharomyces cerevisiae. We grouped all enzyme pairs according to the topological distance that the catalyzed reactions have in the metabolic network and performed a statistical analysis of reported enzyme-enzyme interactions within these groups. We found a higher frequency of reported enzyme-enzyme interactions within the group of enzymes catalyzing reactions that are adjacent in the network, i.e. sharing at least one metabolite. As some of these interacting enzymes have already been implicated in metabolic channeling our analysis may provide a useful screening for candidates of this phenomenon. To check for a possible regulatory role of interactions between enzymes catalyzing non-neighboring reactions, we determined potentially regulatory enzymes using connectivity in the network and absolute change of Gibbs free energy. Indeed a higher portion of reported interactions pertain to such potentially regulatory enzymes.

  8. Overcoming the metabolic burden of protein secretion in Schizosaccharomyces pombe--a quantitative approach using 13C-based metabolic flux analysis.

    PubMed

    Klein, Tobias; Lange, Sabrina; Wilhelm, Nadine; Bureik, Matthias; Yang, Tae-Hoon; Heinzle, Elmar; Schneider, Konstantin

    2014-01-01

    Protein secretion in yeast is generally associated with a burden to cellular metabolism. To investigate this metabolic burden in Schizosaccharomyces pombe, we constructed a set of strains secreting the model protein maltase in different amounts. We quantified the influence of protein secretion on the metabolism applying (13)C-based metabolic flux analysis in chemostat cultures. Analysis of the macromolecular biomass composition revealed an increase in cellular lipid content at elevated levels of protein secretion and we observed altered metabolic fluxes in the pentose phosphate pathway, the TCA cycle, and around the pyruvate node including mitochondrial NADPH supply. Supplementing acetate to glucose or glycerol minimal media was found to improve protein secretion, accompanied by an increased cellular lipid content and carbon flux through the TCA cycle as well as increased mitochondrial NADPH production. Thus, systematic metabolic analyses can assist in identifying factors limiting protein secretion and in deriving strategies to overcome these limitations.

  9. The origin of modern metabolic networks inferred from phylogenomic analysis of protein architecture.

    PubMed

    Caetano-Anollés, Gustavo; Kim, Hee Shin; Mittenthal, Jay E

    2007-05-29

    Metabolism represents a complex collection of enzymatic reactions and transport processes that convert metabolites into molecules capable of supporting cellular life. Here we explore the origins and evolution of modern metabolism. Using phylogenomic information linked to the structure of metabolic enzymes, we sort out recruitment processes and discover that most enzymatic activities were associated with the nine most ancient and widely distributed protein fold architectures. An analysis of newly discovered functions showed enzymatic diversification occurred early, during the onset of the modern protein world. Most importantly, phylogenetic reconstruction exercises and other evidence suggest strongly that metabolism originated in enzymes with the P-loop hydrolase fold in nucleotide metabolism, probably in pathways linked to the purine metabolic subnetwork. Consequently, the first enzymatic takeover of an ancient biochemistry or prebiotic chemistry was related to the synthesis of nucleotides for the RNA world. PMID:17517598

  10. L-Carnosine Affects the Growth of Saccharomyces cerevisiae in a Metabolism-Dependent Manner

    PubMed Central

    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. PMID:22984600

  11. 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

    2016-01-01

    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. PMID:27629523

  12. 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

  13. 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.

  14. Cannibalism Affects Core Metabolic Processes in Helicoverpa armigera Larvae-A 2D NMR Metabolomics Study.

    PubMed

    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-(13)C 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 Central

    Kong, Zhiqiang; Li, Minmin; An, Jingjing; Chen, Jieying; Bao, Yuming; Francis, Frédéric; Dai, Xiaofeng

    2016-01-01

    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. PMID:27629523

  16. 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.

  17. Nectar resource limitation affects butterfly flight performance and metabolism differently in intensive and extensive agricultural landscapes.

    PubMed

    Lebeau, Julie; Wesselingh, Renate A; Van Dyck, Hans

    2016-05-11

    Flight is an essential biological ability of many insects, but is energetically costly. Environments under rapid human-induced change are characterized by habitat fragmentation and may impose constraints on the energy income budget of organisms. This may, in turn, affect locomotor performance and willingness to fly. We tested flight performance and metabolic rates in meadow brown butterflies (Maniola jurtina) of two contrasted agricultural landscapes: intensively managed, nectar-poor (IL) versus extensively managed, nectar-rich landscapes (EL). Young female adults were submitted to four nectar treatments (i.e. nectar quality and quantity) in outdoor flight cages. IL individuals had better flight capacities in a flight mill and had lower resting metabolic rates (RMR) than EL individuals, except under the severest treatment. Under this treatment, RMR increased in IL individuals, but decreased in EL individuals; flight performance was maintained by IL individuals, but dropped by a factor 2.5 in EL individuals. IL individuals had more canalized (i.e. less plastic) responses relative to the nectar treatments than EL individuals. Our results show significant intraspecific variation in the locomotor and metabolic response of a butterfly to different energy income regimes relative to the landscape of origin. Ecophysiological studies help to improve our mechanistic understanding of the eco-evolutionary impact of anthropogenic environments on rare and widespread species. PMID:27147100

  18. Nectar resource limitation affects butterfly flight performance and metabolism differently in intensive and extensive agricultural landscapes.

    PubMed

    Lebeau, Julie; Wesselingh, Renate A; Van Dyck, Hans

    2016-05-11

    Flight is an essential biological ability of many insects, but is energetically costly. Environments under rapid human-induced change are characterized by habitat fragmentation and may impose constraints on the energy income budget of organisms. This may, in turn, affect locomotor performance and willingness to fly. We tested flight performance and metabolic rates in meadow brown butterflies (Maniola jurtina) of two contrasted agricultural landscapes: intensively managed, nectar-poor (IL) versus extensively managed, nectar-rich landscapes (EL). Young female adults were submitted to four nectar treatments (i.e. nectar quality and quantity) in outdoor flight cages. IL individuals had better flight capacities in a flight mill and had lower resting metabolic rates (RMR) than EL individuals, except under the severest treatment. Under this treatment, RMR increased in IL individuals, but decreased in EL individuals; flight performance was maintained by IL individuals, but dropped by a factor 2.5 in EL individuals. IL individuals had more canalized (i.e. less plastic) responses relative to the nectar treatments than EL individuals. Our results show significant intraspecific variation in the locomotor and metabolic response of a butterfly to different energy income regimes relative to the landscape of origin. Ecophysiological studies help to improve our mechanistic understanding of the eco-evolutionary impact of anthropogenic environments on rare and widespread species.

  19. Lipoic acid entrains the hepatic circadian clock and lipid metabolic proteins that have been desynchronized with advanced age

    SciTech Connect

    Keith, Dove; Finlay, Liam; Butler, Judy; Gómez, Luis; Smith, Eric; Moreau, Régis; Hagen, Tory

    2014-07-18

    Highlights: • 24 month old rats were supplemented with 0.2% lipoic acid in the diet for 2 weeks. • Lipoic acid shifts phase of core circadian clock proteins. • Lipoic acid corrects age-induced desynchronized lipid metabolism rhythms. - Abstract: It is well established that lipid metabolism is controlled, in part, by circadian clocks. However, circadian clocks lose temporal precision with age and correlates with elevated incidence in dyslipidemia and metabolic syndrome in older adults. Because our lab has shown that lipoic acid (LA) improves lipid homeostasis in aged animals, we hypothesized that LA affects the circadian clock to achieve these results. We fed 24 month old male F344 rats a diet supplemented with 0.2% (w/w) LA for 2 weeks prior to sacrifice and quantified hepatic circadian clock protein levels and clock-controlled lipid metabolic enzymes. LA treatment caused a significant phase-shift in the expression patterns of the circadian clock proteins Period (Per) 2, Brain and Muscle Arnt-Like1 (BMAL1), and Reverse Erythroblastosis virus (Rev-erb) β without altering the amplitude of protein levels during the light phase of the day. LA also significantly altered the oscillatory patterns of clock-controlled proteins associated with lipid metabolism. The level of peroxisome proliferator-activated receptor (PPAR) α was significantly increased and acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) were both significantly reduced, suggesting that the LA-supplemented aged animals are in a catabolic state. We conclude that LA remediates some of the dyslipidemic processes associated with advanced age, and this mechanism may be at least partially through entrainment of circadian clocks.

  20. Deletion of GPR40 Impairs Glucose-Induced Insulin Secretion In Vivo in Mice Without Affecting Intracellular Fuel Metabolism in Islets

    SciTech Connect

    Alquier, Thierry; Peyot, Marie-Line; Latour, M. G.; Kebede, Melkam; Sorensen, Christina M.; Gesta, Stephane; Kahn, C. R.; Smith, Richard D.; Jetton, Thomas L.; Metz, Thomas O.; Prentki, Marc; Poitout, Vincent J.

    2009-11-01

    The G protein-coupled receptor GPR40 mediates fatty-acid potentiation of glucose-stimulated insulin secretion, but its contribution to insulin secretion in vivo and mechanisms of action remain uncertain. This study was aimed to ascertain whether GPR40 controls insulin secretion in vivo and modulates intracellular fuel metabolism in islets. We observed that glucose- and arginine-stimulated insulin secretion, assessed by hyperglycemic clamps, was decreased by approximately 60% in GPR40 knock-out (KO) fasted and fed mice, without changes in insulin sensitivity assessed by hyperinsulinemic-euglycemic clamps. Glucose and palmitate metabolism were not affected by GPR40 deletion. Lipid profiling revealed a similar increase in triglyceride and decrease in lysophosphatidylethanolamine species in WT and KO islets in response to palmitate. These results demonstrate that GPR40 regulates insulin secretion in vivo not only in response to fatty acids but also to glucose and arginine, without altering intracellular fuel metabolism.

  1. Oxygen Affects Gut Bacterial Colonization and Metabolic Activities in a Gnotobiotic Cockroach Model

    PubMed Central

    Tegtmeier, Dorothee; Thompson, Claire L.; Schauer, Christine

    2015-01-01

    The gut microbiota of termites and cockroaches represents complex metabolic networks of many diverse microbial populations. The distinct microenvironmental conditions within the gut and possible interactions among the microorganisms make it essential to investigate how far the metabolic properties of pure cultures reflect their activities in their natural environment. We established the cockroach Shelfordella lateralis as a gnotobiotic model and inoculated germfree nymphs with two bacterial strains isolated from the guts of conventional cockroaches. Fluorescence microscopy revealed that both strains specifically colonized the germfree hindgut. In diassociated cockroaches, the facultatively anaerobic strain EbSL (a new species of Enterobacteriaceae) always outnumbered the obligately anaerobic strain FuSL (a close relative of Fusobacterium varium), irrespective of the sequence of inoculation, which showed that precolonization by facultatively anaerobic bacteria does not necessarily favor colonization by obligate anaerobes. Comparison of the fermentation products of the cultures formed in vitro with those accumulated in situ indicated that the gut environment strongly affected the metabolic activities of both strains. The pure cultures formed the typical products of mixed-acid or butyrate fermentation, whereas the guts of gnotobiotic cockroaches accumulated mostly lactate and acetate. Similar shifts toward more-oxidized products were observed when the pure cultures were exposed to oxygen, which corroborated the strong effects of oxygen on the metabolic fluxes previously observed in termite guts. Oxygen microsensor profiles of the guts of germfree, gnotobiotic, and conventional cockroaches indicated that both gut tissue and microbiota contribute to oxygen consumption and suggest that the oxygen status influences the colonization success. PMID:26637604

  2. Oxygen Affects Gut Bacterial Colonization and Metabolic Activities in a Gnotobiotic Cockroach Model.

    PubMed

    Tegtmeier, Dorothee; Thompson, Claire L; Schauer, Christine; Brune, Andreas

    2016-02-01

    The gut microbiota of termites and cockroaches represents complex metabolic networks of many diverse microbial populations. The distinct microenvironmental conditions within the gut and possible interactions among the microorganisms make it essential to investigate how far the metabolic properties of pure cultures reflect their activities in their natural environment. We established the cockroach Shelfordella lateralis as a gnotobiotic model and inoculated germfree nymphs with two bacterial strains isolated from the guts of conventional cockroaches. Fluorescence microscopy revealed that both strains specifically colonized the germfree hindgut. In diassociated cockroaches, the facultatively anaerobic strain EbSL (a new species of Enterobacteriaceae) always outnumbered the obligately anaerobic strain FuSL (a close relative of Fusobacterium varium), irrespective of the sequence of inoculation, which showed that precolonization by facultatively anaerobic bacteria does not necessarily favor colonization by obligate anaerobes. Comparison of the fermentation products of the cultures formed in vitro with those accumulated in situ indicated that the gut environment strongly affected the metabolic activities of both strains. The pure cultures formed the typical products of mixed-acid or butyrate fermentation, whereas the guts of gnotobiotic cockroaches accumulated mostly lactate and acetate. Similar shifts toward more-oxidized products were observed when the pure cultures were exposed to oxygen, which corroborated the strong effects of oxygen on the metabolic fluxes previously observed in termite guts. Oxygen microsensor profiles of the guts of germfree, gnotobiotic, and conventional cockroaches indicated that both gut tissue and microbiota contribute to oxygen consumption and suggest that the oxygen status influences the colonization success. PMID:26637604

  3. Oxygen Affects Gut Bacterial Colonization and Metabolic Activities in a Gnotobiotic Cockroach Model.

    PubMed

    Tegtmeier, Dorothee; Thompson, Claire L; Schauer, Christine; Brune, Andreas

    2015-12-04

    The gut microbiota of termites and cockroaches represents complex metabolic networks of many diverse microbial populations. The distinct microenvironmental conditions within the gut and possible interactions among the microorganisms make it essential to investigate how far the metabolic properties of pure cultures reflect their activities in their natural environment. We established the cockroach Shelfordella lateralis as a gnotobiotic model and inoculated germfree nymphs with two bacterial strains isolated from the guts of conventional cockroaches. Fluorescence microscopy revealed that both strains specifically colonized the germfree hindgut. In diassociated cockroaches, the facultatively anaerobic strain EbSL (a new species of Enterobacteriaceae) always outnumbered the obligately anaerobic strain FuSL (a close relative of Fusobacterium varium), irrespective of the sequence of inoculation, which showed that precolonization by facultatively anaerobic bacteria does not necessarily favor colonization by obligate anaerobes. Comparison of the fermentation products of the cultures formed in vitro with those accumulated in situ indicated that the gut environment strongly affected the metabolic activities of both strains. The pure cultures formed the typical products of mixed-acid or butyrate fermentation, whereas the guts of gnotobiotic cockroaches accumulated mostly lactate and acetate. Similar shifts toward more-oxidized products were observed when the pure cultures were exposed to oxygen, which corroborated the strong effects of oxygen on the metabolic fluxes previously observed in termite guts. Oxygen microsensor profiles of the guts of germfree, gnotobiotic, and conventional cockroaches indicated that both gut tissue and microbiota contribute to oxygen consumption and suggest that the oxygen status influences the colonization success.

  4. Isolation of a Genomic Region Affecting Most Components of Metabolic Syndrome in a Chromosome-16 Congenic Rat Model

    PubMed Central

    Šedová, Lucie; Pravenec, Michal; Křenová, Drahomíra; Kazdová, Ludmila; Zídek, Václav; Krupková, Michaela; Liška, František; Křen, Vladimír; Šeda, Ondřej

    2016-01-01

    Metabolic syndrome is a highly prevalent human disease with substantial genomic and environmental components. Previous studies indicate the presence of significant genetic determinants of several features of metabolic syndrome on rat chromosome 16 (RNO16) and the syntenic regions of human genome. We derived the SHR.BN16 congenic strain by introgression of a limited RNO16 region from the Brown Norway congenic strain (BN-Lx) into the genomic background of the spontaneously hypertensive rat (SHR) strain. We compared the morphometric, metabolic, and hemodynamic profiles of adult male SHR and SHR.BN16 rats. We also compared in silico the DNA sequences for the differential segment in the BN-Lx and SHR parental strains. SHR.BN16 congenic rats had significantly lower weight, decreased concentrations of total triglycerides and cholesterol, and improved glucose tolerance compared with SHR rats. The concentrations of insulin, free fatty acids, and adiponectin were comparable between the two strains. SHR.BN16 rats had significantly lower systolic (18–28 mmHg difference) and diastolic (10–15 mmHg difference) blood pressure throughout the experiment (repeated-measures ANOVA, P < 0.001). The differential segment spans approximately 22 Mb of the telomeric part of the short arm of RNO16. The in silico analyses revealed over 1200 DNA variants between the BN-Lx and SHR genomes in the SHR.BN16 differential segment, 44 of which lead to missense mutations, and only eight of which (in Asb14, Il17rd, Itih1, Syt15, Ercc6, RGD1564958, Tmem161a, and Gatad2a genes) are predicted to be damaging to the protein product. Furthermore, a number of genes within the RNO16 differential segment associated with metabolic syndrome components in human studies showed polymorphisms between SHR and BN-Lx (including Lpl, Nrg3, Pbx4, Cilp2, and Stab1). Our novel congenic rat model demonstrates that a limited genomic region on RNO16 in the SHR significantly affects many of the features of metabolic syndrome

  5. Isolation of a Genomic Region Affecting Most Components of Metabolic Syndrome in a Chromosome-16 Congenic Rat Model.

    PubMed

    Šedová, Lucie; Pravenec, Michal; Křenová, Drahomíra; Kazdová, Ludmila; Zídek, Václav; Krupková, Michaela; Liška, František; Křen, Vladimír; Šeda, Ondřej

    2016-01-01

    Metabolic syndrome is a highly prevalent human disease with substantial genomic and environmental components. Previous studies indicate the presence of significant genetic determinants of several features of metabolic syndrome on rat chromosome 16 (RNO16) and the syntenic regions of human genome. We derived the SHR.BN16 congenic strain by introgression of a limited RNO16 region from the Brown Norway congenic strain (BN-Lx) into the genomic background of the spontaneously hypertensive rat (SHR) strain. We compared the morphometric, metabolic, and hemodynamic profiles of adult male SHR and SHR.BN16 rats. We also compared in silico the DNA sequences for the differential segment in the BN-Lx and SHR parental strains. SHR.BN16 congenic rats had significantly lower weight, decreased concentrations of total triglycerides and cholesterol, and improved glucose tolerance compared with SHR rats. The concentrations of insulin, free fatty acids, and adiponectin were comparable between the two strains. SHR.BN16 rats had significantly lower systolic (18-28 mmHg difference) and diastolic (10-15 mmHg difference) blood pressure throughout the experiment (repeated-measures ANOVA, P < 0.001). The differential segment spans approximately 22 Mb of the telomeric part of the short arm of RNO16. The in silico analyses revealed over 1200 DNA variants between the BN-Lx and SHR genomes in the SHR.BN16 differential segment, 44 of which lead to missense mutations, and only eight of which (in Asb14, Il17rd, Itih1, Syt15, Ercc6, RGD1564958, Tmem161a, and Gatad2a genes) are predicted to be damaging to the protein product. Furthermore, a number of genes within the RNO16 differential segment associated with metabolic syndrome components in human studies showed polymorphisms between SHR and BN-Lx (including Lpl, Nrg3, Pbx4, Cilp2, and Stab1). Our novel congenic rat model demonstrates that a limited genomic region on RNO16 in the SHR significantly affects many of the features of metabolic syndrome.

  6. Nonsense mutations in the human. beta. -globin gene affect mRNA metabolism

    SciTech Connect

    Baserga, S.J.; Benz, E.J. Jr. )

    1988-04-01

    A number of premature translation termination mutations (nonsense mutations) have been described in the human {alpha}- and {beta}-globin genes. Studies on mRNA isolated from patients with {beta}{sup 0}-thalassemia have shown that for both the {beta}-17 and the {beta}-39 mutations less than normal levels of {beta}-globin mRNA accumulate in peripheral blood cells. (The codon at which the mutation occurs designates the name of the mutation; there are 146 codons in human {beta}-globin mRNA). In vitro studies using the cloned {beta}-39 gene have reproduced this effect in a heterologous transfection system and have suggested that the defect resides in intranuclear metabolism. The authors have asked if this phenomenon of decreased mRNA accumulation is a general property of nonsense mutations and if the effect depends on the location or the type of mutation. Toward this end, they have studied the effect of five nonsense mutations and two missense mutations on the expression of human {beta}-globin mRNA in a heterologous transfection system. In all cases studied, the presence of a translation termination codon correlates with a decrease in the steady-state level of mRNA. The data suggest that the metabolism of a mammalian mRNA is affected by the presence of a mutation that affects translation.

  7. Litter Environment Affects Behavior and Brain Metabolic Activity of Adult Knockout Mice

    PubMed Central

    Crews, David; Rushworth, David; Gonzalez-Lima, Francisco; Ogawa, Sonoko

    2009-01-01

    In mammals, the formative environment for social and anxiety-related behaviors is the family unit; in the case of rodents, this is the litter and the mother-young bond. A deciding factor in this environment is the sex ratio of the litter and, in the case of mice lacking functional copies of gene(s), the ratio of the various genotypes in the litter. Both Sex and Genotype ratios of the litter affect the nature and quality of the individual's behavior later in adulthood, as well as metabolic activity in brain nuclei that underlie these behaviors. Mice were raised in litters reconstituted shortly after to birth to control for sex ratio and genotype ratio (wild type pups versus pups lacking a functional estrogen receptor α). In both males and females, the Sex and Genotype of siblings in the litter affected aggressive behaviors as well as patterns of metabolic activity in limbic nuclei in the social behavior network later in adulthood. Further, this pattern in males varied depending upon the Genotype of their brothers and sisters. Principal Components Analysis revealed two components comprised of several amygdalar and hypothalamic nuclei; the VMH showed strong correlations in both clusters, suggesting its pivotal nature in the organization of two neural networks. PMID:19707539

  8. Use of Designer G Protein-Coupled Receptors to Dissect Metabolic Pathways.

    PubMed

    Wess, Jürgen

    2016-09-01

    G protein-coupled receptors (GPCRs) regulate virtually all metabolic processes, including glucose and energy homeostasis. Recently, the use of designer GPCRs referred to as designer receptors exclusively activated by designer drug (DREADDs) has made it possible to dissect metabolically relevant GPCR signaling pathways in a temporally and spatially controlled fashion in vivo. PMID:27381463

  9. Markers of Bone Metabolism Are Affected by Renal Function and Growth Hormone Therapy in Children with Chronic Kidney Disease

    PubMed Central

    Doyon, Anke; Fischer, Dagmar-Christiane; Bayazit, Aysun Karabay; Canpolat, Nur; Duzova, Ali; Sözeri, Betül; Bacchetta, Justine; Balat, Ayse; Büscher, Anja; Candan, Cengiz; Cakar, Nilgun; Donmez, Osman; Dusek, Jiri; Heckel, Martina; Klaus, Günter; Mir, Sevgi; Özcelik, Gül; Sever, Lale; Shroff, Rukshana; Vidal, Enrico; Wühl, Elke; Gondan, Matthias; Melk, Anette; Querfeld, Uwe; Haffner, Dieter; Schaefer, Franz

    2015-01-01

    Objectives The extent and relevance of altered bone metabolism for statural growth in children with chronic kidney disease is controversial. We analyzed the impact of renal dysfunction and recombinant growth hormone therapy on a panel of serum markers of bone metabolism in a large pediatric chronic kidney disease cohort. Methods Bone alkaline phosphatase (BAP), tartrate-resistant acid phosphatase 5b (TRAP5b), sclerostin and C-terminal FGF-23 (cFGF23) normalized for age and sex were analyzed in 556 children aged 6–18 years with an estimated glomerular filtration rate (eGFR) of 10–60 ml/min/1.73m2. 41 children receiving recombinant growth hormone therapy were compared to an untreated matched control group. Results Standardized levels of BAP, TRAP5b and cFGF-23 were increased whereas sclerostin was reduced. BAP was correlated positively and cFGF-23 inversely with eGFR. Intact serum parathormone was an independent positive predictor of BAP and TRAP5b and negatively associated with sclerostin. BAP and TRAP5B were negatively affected by increased C-reactive protein levels. In children receiving recombinant growth hormone, BAP was higher and TRAP5b lower than in untreated controls. Sclerostin levels were in the normal range and higher than in untreated controls. Serum sclerostin and cFGF-23 independently predicted height standard deviation score, and BAP and TRAP5b the prospective change in height standard deviation score. Conclusion Markers of bone metabolism indicate a high-bone turnover state in children with chronic kidney disease. Growth hormone induces an osteoanabolic pattern and normalizes osteocyte activity. The osteocyte markers cFGF23 and sclerostin are associated with standardized height, and the markers of bone turnover predict height velocity. PMID:25659076

  10. Study of Stationary Phase Metabolism Via Isotopomer Analysis of Amino Acids from an Isolated Protein

    SciTech Connect

    Shaikh, AfshanS.; Tang, YinjieJ.; Mukhopadhyay, Aindrila; Martin, Hector Garcia; Gin, Jennifer; Benke, Peter; Keasling, Jay D.

    2009-09-14

    Microbial production of many commercially important secondary metabolites occurs during stationary phase, and methods to measure metabolic flux during this growth phase would be valuable. Metabolic flux analysis is often based on isotopomer information from proteinogenic amino acids. As such, flux analysis primarily reflects the metabolism pertinent to the growth phase during which most proteins are synthesized. To investigate central metabolism and amino acids synthesis activity during stationary phase, addition of fully 13C-labeled glucose followed by induction of green fluorescent protein (GFP) expression during stationary phase was used. Our results indicate that Escherichia coli was able to produce new proteins (i.e., GFP) in the stationary phase, and the amino acids in GFP were mostly from degraded proteins synthesized during the exponential growth phase. Among amino acid biosynthetic pathways, only those for serine, alanine, glutamate/glutamine, and aspartate/asparagine had significant activity during the stationary phase.

  11. Hepatic autophagy contributes to the metabolic response to dietary protein restriction.

    PubMed

    Henagan, Tara M; Laeger, Thomas; Navard, Alexandra M; Albarado, Diana; Noland, Robert C; Stadler, Krisztian; Elks, Carrie M; Burk, David; Morrison, Christopher D

    2016-06-01

    Autophagy is an essential cellular response which acts to release stored cellular substrates during nutrient restriction, and particularly plays a key role in the cellular response to amino acid restriction. However, there has been limited work testing whether the induction of autophagy is required for adaptive metabolic responses to dietary protein restriction in the whole animal. Here, we found that moderate dietary protein restriction led to a series of metabolic changes in rats, including increases in food intake and energy expenditure, the downregulation of hepatic fatty acid synthesis gene expression and reduced markers of hepatic mitochondrial number. Importantly, these effects were also associated with an induction of hepatic autophagy. To determine if the induction of autophagy contributes to these metabolic effects, we tested the metabolic response to dietary protein restriction in BCL2-AAA mice, which bear a genetic mutation that impairs autophagy induction. Interestingly, BCL2-AAA mice exhibit exaggerated responses in terms of both food intake and energy expenditure, whereas the effects of protein restriction on hepatic metabolism were significantly blunted. These data demonstrate that restriction of dietary protein is sufficient to trigger hepatic autophagy, and that disruption of autophagy significantly alters both hepatic and whole animal metabolic response to dietary protein restriction. PMID:27173459

  12. Glucose Availability and AMP-Activated Protein Kinase Link Energy Metabolism and Innate Immunity in the Bovine Endometrium.

    PubMed

    Turner, Matthew L; Cronin, James G; Noleto, Pablo G; Sheldon, I Martin

    2016-01-01

    Defences against the bacteria that usually infect the endometrium of postpartum cattle are impaired when there is metabolic energy stress, leading to endometritis and infertility. The endometrial response to bacteria depends on innate immunity, with recognition of pathogen-associated molecular patterns stimulating inflammation, characterised by secretion of interleukin (IL)-1β, IL-6 and IL-8. How metabolic stress impacts tissue responses to pathogens is unclear, but integration of energy metabolism and innate immunity means that stressing one system might affect the other. Here we tested the hypothesis that homeostatic pathways integrate energy metabolism and innate immunity in bovine endometrial tissue. Glucose deprivation reduced the secretion of IL-1β, IL-6 and IL-8 from ex vivo organ cultures of bovine endometrium challenged with the pathogen-associated molecular patterns lipopolysaccharide and bacterial lipopeptide. Endometrial inflammatory responses to lipopolysaccharide were also reduced by small molecules that activate or inhibit the intracellular sensor of energy, AMP-activated protein kinase (AMPK). However, inhibition of mammalian target of rapamycin, which is a more global metabolic sensor than AMPK, had little effect on inflammation. Similarly, endometrial inflammatory responses to lipopolysaccharide were not affected by insulin-like growth factor-1, which is an endocrine regulator of metabolism. Interestingly, the inflammatory responses to lipopolysaccharide increased endometrial glucose consumption and induced the Warburg effect, which could exacerbate deficits in glucose availability in the tissue. In conclusion, metabolic energy stress perturbed inflammatory responses to pathogen-associated molecular patterns in bovine endometrial tissue, and the most fundamental regulators of cellular energy, glucose availability and AMPK, had the greatest impact on innate immunity. PMID:26974839

  13. Glucose Availability and AMP-Activated Protein Kinase Link Energy Metabolism and Innate Immunity in the Bovine Endometrium

    PubMed Central

    Turner, Matthew L.; Cronin, James G.; Noleto, Pablo G.; Sheldon, I. Martin

    2016-01-01

    Defences against the bacteria that usually infect the endometrium of postpartum cattle are impaired when there is metabolic energy stress, leading to endometritis and infertility. The endometrial response to bacteria depends on innate immunity, with recognition of pathogen-associated molecular patterns stimulating inflammation, characterised by secretion of interleukin (IL)-1β, IL-6 and IL-8. How metabolic stress impacts tissue responses to pathogens is unclear, but integration of energy metabolism and innate immunity means that stressing one system might affect the other. Here we tested the hypothesis that homeostatic pathways integrate energy metabolism and innate immunity in bovine endometrial tissue. Glucose deprivation reduced the secretion of IL-1β, IL-6 and IL-8 from ex vivo organ cultures of bovine endometrium challenged with the pathogen-associated molecular patterns lipopolysaccharide and bacterial lipopeptide. Endometrial inflammatory responses to lipopolysaccharide were also reduced by small molecules that activate or inhibit the intracellular sensor of energy, AMP-activated protein kinase (AMPK). However, inhibition of mammalian target of rapamycin, which is a more global metabolic sensor than AMPK, had little effect on inflammation. Similarly, endometrial inflammatory responses to lipopolysaccharide were not affected by insulin-like growth factor-1, which is an endocrine regulator of metabolism. Interestingly, the inflammatory responses to lipopolysaccharide increased endometrial glucose consumption and induced the Warburg effect, which could exacerbate deficits in glucose availability in the tissue. In conclusion, metabolic energy stress perturbed inflammatory responses to pathogen-associated molecular patterns in bovine endometrial tissue, and the most fundamental regulators of cellular energy, glucose availability and AMPK, had the greatest impact on innate immunity. PMID:26974839

  14. Campylobacter jejuni CsrA Regulates Metabolic and Virulence Associated Proteins and Is Necessary for Mouse Colonization.

    PubMed

    Fields, Joshua A; Li, Jiaqi; Gulbronson, Connor J; Hendrixson, David R; Thompson, Stuart A

    2016-01-01

    Campylobacter jejuni infection is a leading bacterial cause of gastroenteritis and a common antecedent leading to Gullian-Barré syndrome. Our previous data suggested that the RNA-binding protein CsrA plays an important role in regulating several important phenotypes including motility, biofilm formation, and oxidative stress resistance. In this study, we compared the proteomes of wild type, csrA mutant, and complemented csrA mutant C. jejuni strains in an effort to elucidate the mechanisms by which CsrA affects virulence phenotypes. The putative CsrA regulon was more pronounced at stationary phase (111 regulated proteins) than at mid-log phase (25 regulated proteins). Proteins displaying altered expression in the csrA mutant included diverse metabolic functions, with roles in amino acid metabolism, TCA cycle, acetate metabolism, and various other cell processes, as well as pathogenesis-associated characteristics such as motility, chemotaxis, oxidative stress resistance, and fibronectin binding. The csrA mutant strain also showed altered autoagglutination kinetics when compared to the wild type. CsrA specifically bound the 5' end of flaA mRNA, and we demonstrated that CsrA is a growth-phase dependent repressor of FlaA expression. Finally, the csrA mutant exhibited reduced ability to colonize in a mouse model when in competition with the wild type, further underscoring the role of CsrA in C. jejuni colonization and pathogenesis.

  15. Campylobacter jejuni CsrA Regulates Metabolic and Virulence Associated Proteins and Is Necessary for Mouse Colonization

    PubMed Central

    Fields, Joshua A.; Li, Jiaqi; Gulbronson, Connor J.; Hendrixson, David R.

    2016-01-01

    Campylobacter jejuni infection is a leading bacterial cause of gastroenteritis and a common antecedent leading to Gullian-Barré syndrome. Our previous data suggested that the RNA-binding protein CsrA plays an important role in regulating several important phenotypes including motility, biofilm formation, and oxidative stress resistance. In this study, we compared the proteomes of wild type, csrA mutant, and complemented csrA mutant C. jejuni strains in an effort to elucidate the mechanisms by which CsrA affects virulence phenotypes. The putative CsrA regulon was more pronounced at stationary phase (111 regulated proteins) than at mid-log phase (25 regulated proteins). Proteins displaying altered expression in the csrA mutant included diverse metabolic functions, with roles in amino acid metabolism, TCA cycle, acetate metabolism, and various other cell processes, as well as pathogenesis-associated characteristics such as motility, chemotaxis, oxidative stress resistance, and fibronectin binding. The csrA mutant strain also showed altered autoagglutination kinetics when compared to the wild type. CsrA specifically bound the 5’ end of flaA mRNA, and we demonstrated that CsrA is a growth-phase dependent repressor of FlaA expression. Finally, the csrA mutant exhibited reduced ability to colonize in a mouse model when in competition with the wild type, further underscoring the role of CsrA in C. jejuni colonization and pathogenesis. PMID:27257952

  16. 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

  17. Altered development and protein metabolism in skeletal muscles of broiler chickens (Gallus gallus domesticus) by corticosterone.

    PubMed

    Dong, H; Lin, H; Jiao, H C; Song, Z G; Zhao, J P; Jiang, K J

    2007-05-01

    Two trials were conducted to investigate the effect of corticosterone (CORT) on protein metabolism and the amino acid composition in muscle tissues of broiler chickens (Gallus gallus domesticus). In Trial 1, two groups of 30 broiler chickens were subjected to control or CORT treatment (30 mg/kg diet) from 28 to 39 days of age. In Trial 2, three groups of chickens of 28 days of age were randomly subjected to one of the following treatments for 7 days: CORT (30 mg/kg diet), pair-fed (maintaining the same feed intake as CORT treatment) and control treatments. The body mass gain and feed efficiency was significantly decreased by CORT treatment, while the food intake was decreased. The breast and thigh masses (% body mass) were significantly suppressed by CORT treatment, while the abdominal fat and liver masses (%) were obviously increased. The plasma levels of glucose, urate and total amino acid were significantly elevated by CORT treatment. The capacity for protein synthesis, estimated by RNA:protein ratio, were significantly suppressed by CORT in M. pectoralis major and M. biceps femoris. The 3-methylhistidine concentrations were significantly increased in both M. pectoralis major and M. biceps femoris of CORT chickens, compared to control but not the pair-fed chickens. The amino acid composition of M. pectoralis major and M. biceps femoris was not significantly affected by CORT treatment. In conclusion, the arrested growth in skeletal muscles induced by CORT administration has tissue specificity. The CORT treatment retards the growth of skeletal muscle by suppressed protein synthesis and augmented protein catabolism.

  18. Aroclor 1254, a developmental neurotoxicant, alters energy metabolism- and intracellular signaling-associated protein networks in rat cerebellum and hippocampus

    SciTech Connect

    Kodavanti, Prasada Rao S.; Osorio, Cristina; Royland, Joyce E.; Ramabhadran, Ram; Alzate, Oscar

    2011-11-15

    The vast literature on the mode of action of polychlorinated biphenyls (PCBs) indicates that PCBs are a unique model for understanding the mechanisms of toxicity of environmental mixtures of persistent chemicals. PCBs have been shown to adversely affect psychomotor function and learning and memory in humans. Although the molecular mechanisms for PCB effects are unclear, several studies indicate that the disruption of Ca{sup 2+}-mediated signal transduction plays significant roles in PCB-induced developmental neurotoxicity. Culminating events in signal transduction pathways include the regulation of gene and protein expression, which affects the growth and function of the nervous system. Our previous studies showed changes in gene expression related to signal transduction and neuronal growth. In this study, protein expression following developmental exposure to PCB is examined. Pregnant rats (Long Evans) were dosed with 0.0 or 6.0 mg/kg/day of Aroclor-1254 from gestation day 6 through postnatal day (PND) 21, and the cerebellum and hippocampus from PND14 animals were analyzed to determine Aroclor 1254-induced differential protein expression. Two proteins were found to be differentially expressed in the cerebellum following PCB exposure while 18 proteins were differentially expressed in the hippocampus. These proteins are related to energy metabolism in mitochondria (ATP synthase, sub unit {beta} (ATP5B), creatine kinase, and malate dehydrogenase), calcium signaling (voltage-dependent anion-selective channel protein 1 (VDAC1) and ryanodine receptor type II (RyR2)), and growth of the nervous system (dihydropyrimidinase-related protein 4 (DPYSL4), valosin-containing protein (VCP)). Results suggest that Aroclor 1254-like persistent chemicals may alter energy metabolism and intracellular signaling, which might result in developmental neurotoxicity. -- Highlights: Black-Right-Pointing-Pointer We performed brain proteomic analysis of rats exposed to the neurotoxicant

  19. Changes in gravity affect gene expression, protein modulation and metabolite pools of arabidopsis

    NASA Astrophysics Data System (ADS)

    Hampp, R.; Martzivanou, M.; Maier, R. M.; Magel, E.

    Callus cultures of Arabidopsis thaliana (cv. Columbia) in Petri dishes / suspension cultures were exposed to altered g-forces by centrifugation (1 to 10 g), klinorotation, and μ g (sounding rocket flights). Using semi-quantitative RT-PCR, transcripts of genes coding for metabolic key enzymes (ADP-glucose pyrophosphorylase, ADPG-PP; ß-amylase, fructose-1,6-bisphosphatase, FBPase; glyceraldehyde-P dehydrogenase, GAPDH; hydroxymethylglutaryl-CoA reductase, HMG; phenylalanine-ammonium-lyase, PAL; PEP carboxylase, PEPC) were used to monitor threshold conditions for g-number (all) and time of exposure (ß-amylase) which led to altered amounts of the gene product. Exposure to approx. 5 g and higher for 1h resulted in altered transcript levels: transcripts of ß-amylase, PAL, and PEPC were increased, those of ADPG-PP decreased, while those of FBPase, GAPDH, and HMG were not affected. This probably indicates a shift from starch synthesis to starch degradation and increased rates of anaplerosis (PEPC: supply of ketoacids for amino acid synthesis). In order to get more information about g-related effects on gene expression, we used a 1h-exposure to 7 g for a microarray analysis. Transcripts of more than 200 genes were significantly increased in amount (ratio 7g / 1g control; 21.6 and larger). They fall into several categories. Transcripts coding for enzymes of major pathways form the largest group (25%), followed by gene products involved in cellular organisation and cell wall formation / rearrangement (17%), signalling, phosphorylation/dephosphorylation (12%), proteolysis and transport (10% each), hormone synthesis plus related events (8%), defense (4%), stress-response (2%), and gravisensing (2%). Many of the alterations are part of a general stress response, but some changes related to the synthesis / rearrangement of cell wall components could be more hyper-g-specific. Using macroarrays with selected genes according to our hypergravity study (metabolism / signalling

  20. Interplay of Breast Cancer Resistance Protein (BCRP) and Metabolizing Enzymes.

    PubMed

    Tian, Ye; Bian, Yicong; Jiang, Yan; Qian, Sainan; Yu, Aiming; Zeng, Su

    2015-01-01

    The recent identification of the interplay between metabolizing enzymes and BCRP has drawn more and more attention from people. BCRP, a transporter belonging to ATP-binding cassette (ABC) family, has been hypothesized to play roles in many aspects including protecting the human body against therapeutics because it is expressed in the tissues that function as barriers in vivo. Efficient coupling of BCRP and metabolizing enzymes enables rapid elimination of foreign compounds from the body because BCRP could facilitate the excretion of metabolites catalyzed by phase I and II enzymes into bile, urine and feces. Without BCRP coupling, pass through the cell membrane may be difficult for them by passive diffusion because of the increment of the molecular weight and water solubility. Thus the metabolism-efflux alliance has extraordinary importance to drug metabolism, distribution, pharmacological effect, toxicity and elimination. In this manuscript, a brief discussion about the interplays of BCRP and metabolizing enzymes in liver, intestine, kidney, lung and other organs were presented and summarized. Many endogenous and exogenous compounds belong to different chemical groups, for instance, the dietary flavonoids and the steroidal hormones were involved. Clarifying the cooperation mechanisms of BCRP and enzymes could lead to a better prediction of drug clearance in vitro.

  1. Interplay of Breast Cancer Resistance Protein (BCRP) and Metabolizing Enzymes.

    PubMed

    Tian, Ye; Bian, Yicong; Jiang, Yan; Qian, Sainan; Yu, Aiming; Zeng, Su

    2015-01-01

    The recent identification of the interplay between metabolizing enzymes and BCRP has drawn more and more attention from people. BCRP, a transporter belonging to ATP-binding cassette (ABC) family, has been hypothesized to play roles in many aspects including protecting the human body against therapeutics because it is expressed in the tissues that function as barriers in vivo. Efficient coupling of BCRP and metabolizing enzymes enables rapid elimination of foreign compounds from the body because BCRP could facilitate the excretion of metabolites catalyzed by phase I and II enzymes into bile, urine and feces. Without BCRP coupling, pass through the cell membrane may be difficult for them by passive diffusion because of the increment of the molecular weight and water solubility. Thus the metabolism-efflux alliance has extraordinary importance to drug metabolism, distribution, pharmacological effect, toxicity and elimination. In this manuscript, a brief discussion about the interplays of BCRP and metabolizing enzymes in liver, intestine, kidney, lung and other organs were presented and summarized. Many endogenous and exogenous compounds belong to different chemical groups, for instance, the dietary flavonoids and the steroidal hormones were involved. Clarifying the cooperation mechanisms of BCRP and enzymes could lead to a better prediction of drug clearance in vitro. PMID:26652256

  2. [Effect of fluorine in drinking water of varying hardness on protein-mineral metabolism of mineralized tissues of rats maintained on a sugar diet].

    PubMed

    Kosenko, K M; Podorozhnia, R P; Henesina, T I

    1993-01-01

    Variations of mineral and protein metabolism in calcified tissues were studied using 32P, 45Ca and 35S methionine in the rats on sugar diet and water of different hardness with F and without it. Hard drinking water without F like soft water and water of medium hardness with F affect metabolism in mineralized tissues preventing the development of carious process. Incorporation of 32P and 45Ca to mineralized tissues, specific radioactivity of 32P and 35S methionine of tooth and bone proteins are lower in rats which drank soft water without F. These parameters increase in rats which received hard water without F almost to the level of animals which received water with F. Ways of the effect of Ca2+ Mg2+ and F on protein and mineral metabolism of calcified tissues of rats on sugar diet (including proteins (osteo-induced, etc., which initiate mineralization) and enzymes are considered.

  3. Integrating the protein and metabolic engineering toolkits for next-generation chemical biosynthesis.

    PubMed

    Pirie, Christopher M; De Mey, Marjan; Jones Prather, Kristala L; Ajikumar, Parayil Kumaran

    2013-04-19

    Through microbial engineering, biosynthesis has the potential to produce thousands of chemicals used in everyday life. Metabolic engineering and synthetic biology are fields driven by the manipulation of genes, genetic regulatory systems, and enzymatic pathways for developing highly productive microbial strains. Fundamentally, it is the biochemical characteristics of the enzymes themselves that dictate flux through a biosynthetic pathway toward the product of interest. As metabolic engineers target sophisticated secondary metabolites, there has been little recognition of the reduced catalytic activity and increased substrate/product promiscuity of the corresponding enzymes compared to those of central metabolism. Thus, fine-tuning these enzymatic characteristics through protein engineering is paramount for developing high-productivity microbial strains for secondary metabolites. Here, we describe the importance of protein engineering for advancing metabolic engineering of secondary metabolism pathways. This pathway integrated enzyme optimization can enhance the collective toolkit of microbial engineering to shape the future of chemical manufacturing.

  4. A Protein Aggregation Based Test for Screening of the Agents Affecting Thermostability of Proteins

    PubMed Central

    Eronina, Tatyana; Borzova, Vera; Maloletkina, Olga; Kleymenov, Sergey; Asryants, Regina; Markossian, Kira; Kurganov, Boris

    2011-01-01

    To search for agents affecting thermal stability of proteins, a test based on the registration of protein aggregation in the regime of heating with a constant rate was used. The initial parts of the dependences of the light scattering intensity (I) on temperature (T) were analyzed using the following empiric equation: I = Kagg(T−T0)2, where Kagg is the parameter characterizing the initial rate of aggregation and T0 is a temperature at which the initial increase in the light scattering intensity is registered. The aggregation data are interpreted in the frame of the model assuming the formation of the start aggregates at the initial stages of the aggregation process. Parameter T0 corresponds to the moment of the origination of the start aggregates. The applicability of the proposed approach was demonstrated on the examples of thermal aggregation of glycogen phosphorylase b from rabbit skeletal muscles and bovine liver glutamate dehydrogenase studied in the presence of agents of different chemical nature. The elaborated approach to the study of protein aggregation may be used for rapid identification of small molecules that interact with protein targets. PMID:21760963

  5. Emergence of Complexity in Protein Functions and Metabolic Networks

    NASA Technical Reports Server (NTRS)

    Pohorille, Andzej

    2009-01-01

    In modern organisms proteins perform a majority of cellular functions, such as chemical catalysis, energy transduction and transport of material across cell walls. Although great strides have been made towards understanding protein evolution, a meaningful extrapolation from contemporary proteins to their earliest ancestors is virtually impossible. In an alternative approach, the origin of water-soluble proteins was probed through the synthesis of very large libraries of random amino acid sequences and subsequently subjecting them to in vitro evolution. In combination with computer modeling and simulations, these experiments allow us to address a number of fundamental questions about the origins of proteins. Can functionality emerge from random sequences of proteins? How did the initial repertoire of functional proteins diversify to facilitate new functions? Did this diversification proceed primarily through drawing novel functionalities from random sequences or through evolution of already existing proto-enzymes? Did protein evolution start from a pool of proteins defined by a frozen accident and other collections of proteins could start a different evolutionary pathway? Although we do not have definitive answers to these questions, important clues have been uncovered. Considerable progress has been also achieved in understanding the origins of membrane proteins. We will address this issue in the example of ion channels - proteins that mediate transport of ions across cell walls. Remarkably, despite overall complexity of these proteins in contemporary cells, their structural motifs are quite simple, with -helices being most common. By combining results of experimental and computer simulation studies on synthetic models and simple, natural channels, I will show that, even though architectures of membrane proteins are not nearly as diverse as those of water-soluble proteins, they are sufficiently flexible to adapt readily to the functional demands arising during

  6. Milk protein for improved metabolic health: a review of the evidence

    PubMed Central

    2013-01-01

    Epidemiological evidence shows that consumption of dairy products is associated with decreased prevalence of metabolic related disorders, whilst evidence from experimental studies points towards dairy protein as a dietary component which may aid prevention of type 2 diabetes (T2DM). Poor metabolic health is a common characteristic of overweight, obesity and aging, and is the forerunner of T2DM and cardiovascular disease (CVD), and an ever increasing global health issue. Progressive loss of metabolic control is evident from a blunting of carbohydrate, fat and protein metabolism, which is commonly manifested through decreased insulin sensitivity, inadequate glucose and lipid control, accompanied by a pro-inflammatory environment and hypertension. Adverse physiological changes such as excess visceral adipose tissue deposition and expansion, lipid overspill and infiltration into liver, muscle and other organs, and sarcopaenia or degenerative loss of skeletal muscle mass and function all underpin this adverse profile. ‘Sarcobesity’ and sarcopaenic diabetes are rapidly growing health issues. As well as through direct mechanisms, dairy protein may indirectly improve metabolic health by aiding loss of body weight and fat mass through enhanced satiety, whilst promoting skeletal muscle growth and function through anabolic effects of dairy protein-derived branch chain amino acids (BCAAs). BCAAs enhance muscle protein synthesis, lean body mass and skeletal muscle metabolic function. The composition and processing of dairy protein has an impact on digestion, absorption, BCAA kinetics and function, hence the optimisation of dairy protein composition through selection and combination of specific protein components in milk may provide a way to maximize benefits for metabolic health. PMID:23822206

  7. Increasing Phosphatidylinositol (4,5)-Bisphosphate Biosynthesis Affects Basal Signaling and Chloroplast Metabolism in Arabidopsis thaliana

    PubMed Central

    Im, Yang Ju; Smith, Caroline M.; Phillippy, Brian Q.; Strand, Deserah; Kramer, David M.; Grunden, Amy M.; Boss, Wendy F.

    2014-01-01

    One challenge in studying the second messenger inositol(1,4,5)-trisphosphate (InsP3) is that it is present in very low amounts and increases only transiently in response to stimuli. To identify events downstream of InsP3, we generated transgenic plants constitutively expressing the high specific activity, human phosphatidylinositol 4-phosphate 5-kinase Iα (HsPIPKIα). PIP5K is the enzyme that synthesizes phosphatidylinositol (4,5)-bisphosphate (PtdIns(4,5)P2); this reaction is flux limiting in InsP3 biosynthesis in plants. Plasma membranes from transgenic Arabidopsis expressing HsPIPKIα had 2–3 fold higher PIP5K specific activity, and basal InsP3 levels in seedlings and leaves were >2-fold higher than wild type. Although there was no significant difference in photosynthetic electron transport, HsPIPKIα plants had significantly higher starch (2–4 fold) and 20% higher anthocyanin compared to controls. Starch content was higher both during the day and at the end of dark period. In addition, transcripts of genes involved in starch metabolism such as SEX1 (glucan water dikinase) and SEX4 (phosphoglucan phosphatase), DBE (debranching enzyme), MEX1 (maltose transporter), APL3 (ADP-glucose pyrophosphorylase) and glucose-6-phosphate transporter (Glc6PT) were up-regulated in the HsPIPKIα plants. Our results reveal that increasing the phosphoinositide (PI) pathway affects chloroplast carbon metabolism and suggest that InsP3 is one component of an inter-organelle signaling network regulating chloroplast metabolism. PMID:27135490

  8. Maternal Obesity Affects Fetal Neurodevelopmental and Metabolic Gene Expression: A Pilot Study

    PubMed Central

    Edlow, Andrea G.; Vora, Neeta L.; Hui, Lisa; Wick, Heather C.; Cowan, Janet M.; Bianchi, Diana W.

    2014-01-01

    Objective One in three pregnant women in the United States is obese. Their offspring are at increased risk for neurodevelopmental and metabolic morbidity. Underlying molecular mechanisms are poorly understood. We performed a global gene expression analysis of mid-trimester amniotic fluid cell-free fetal RNA in obese versus lean pregnant women. Methods This prospective pilot study included eight obese (BMI≥30) and eight lean (BMI<25) women undergoing clinically indicated mid-trimester genetic amniocentesis. Subjects were matched for gestational age and fetal sex. Fetuses with abnormal karyotype or structural anomalies were excluded. Cell-free fetal RNA was extracted from amniotic fluid and hybridized to whole genome expression arrays. Genes significantly differentially regulated in 8/8 obese-lean pairs were identified using paired t-tests with the Benjamini-Hochberg correction (false discovery rate of <0.05). Biological interpretation was performed with Ingenuity Pathway Analysis and the BioGPS gene expression atlas. Results In fetuses of obese pregnant women, 205 genes were significantly differentially regulated. Apolipoprotein D, a gene highly expressed in the central nervous system and integral to lipid regulation, was the most up-regulated gene (9-fold). Apoptotic cell death was significantly down-regulated, particularly within nervous system pathways involving the cerebral cortex. Activation of the transcriptional regulators estrogen receptor, FOS, and STAT3 was predicted in fetuses of obese women, suggesting a pro-estrogenic, pro-inflammatory milieu. Conclusion Maternal obesity affects fetal neurodevelopmental and metabolic gene expression as early as the second trimester. These findings may have implications for postnatal neurodevelopmental and metabolic abnormalities described in the offspring of obese women. PMID:24558408

  9. Prolonged hyperinsulinemia affects metabolic signal transduction markers in a tissue specific manner.

    PubMed

    Campolo, A; de Laat, M A; Keith, L; Gruntmeir, K J; Lacombe, V A

    2016-04-01

    Insulin dysregulation is common in horses although the mechanisms of metabolic dysfunction are poorly understood. We hypothesized that insulin signaling in striated (cardiac and skeletal) muscle and lamellae may be mediated through different receptors as a result of receptor content, and that transcriptional regulation of downstream signal transduction and glucose transport may also differ between tissues sites during hyperinsulinemia. Archived samples from horses treated with a prolonged insulin infusion or a balanced electrolyte solution were used. All treated horses developed marked hyperinsulinemia and clinical laminitis. Protein expression was compared across tissues for the insulin receptor and insulin-like growth factor 1 receptor (IGF-1R) by immunoblotting. Gene expression of metabolic insulin-signaling markers (insulin receptor substrate 1, Akt2, and glycogen synthase kinase 3 beta [GSK-3β]) and glucose transport (basal glucose transporter 1 and insulin-sensitive glucose transporter 4) was evaluated using real-time reverse transcription polymerase chain reaction. Lamellar tissue contained significantly more IGF-1R protein than skeletal muscle, indicating the potential significance of IGF-1R signaling for this tissue. Gene expression of the selected markers of insulin signaling and glucose transport in skeletal muscle and lamellar tissues was unaffected by prolonged hyperinsulinemia. In contrast, the significant upregulation of Akt2, GSK-3β, GLUT1, and GLUT4 gene expression in cardiac tissue suggested that the prolonged hyperinsulinemia induced an increase in insulin sensitivity and a transcriptional activation of glucose transport. Responses to insulin are tissue-specific, and extrapolation of data across tissue sites is inappropriate. PMID:26773366

  10. Arachidonic Acid and Eicosapentaenoic Acid Metabolism in Juvenile Atlantic Salmon as Affected by Water Temperature.

    PubMed

    Norambuena, Fernando; Morais, Sofia; Emery, James A; Turchini, Giovanni M

    2015-01-01

    Salmons raised in aquaculture farms around the world are increasingly subjected to sub-optimal environmental conditions, such as high water temperatures during summer seasons. Aerobic scope increases and lipid metabolism changes are known plasticity responses of fish for a better acclimation to high water temperature. The present study aimed at investigating the effect of high water temperature on the regulation of fatty acid metabolism in juvenile Atlantic salmon fed different dietary ARA/EPA ratios (arachidonic acid, 20:4n-6/ eicosapentaenoic acid, 20:5n-3), with particular focus on apparent in vivo enzyme activities and gene expression of lipid metabolism pathways. Three experimental diets were formulated to be identical, except for the ratio EPA/ARA, and fed to triplicate groups of Atlantic salmon (Salmo salar) kept either at 10°C or 20°C. Results showed that fatty acid metabolic utilisation, and likely also their dietary requirements for optimal performance, can be affected by changes in their relative levels and by environmental temperature in Atlantic salmon. Thus, the increase in temperature, independently from dietary treatment, had a significant effect on the β-oxidation of a fatty acid including EPA, as observed by the apparent in vivo enzyme activity and mRNA expression of pparα -transcription factor in lipid metabolism, including β-oxidation genes- and cpt1 -key enzyme responsible for the movement of LC-PUFA from the cytosol into the mitochondria for β-oxidation-, were both increased at the higher water temperature. An interesting interaction was observed in the transcription and in vivo enzyme activity of Δ5fad-time-limiting enzyme in the biosynthesis pathway of EPA and ARA. Such, at lower temperature, the highest mRNA expression and enzyme activity was recorded in fish with limited supply of dietary EPA, whereas at higher temperature these were recorded in fish with limited ARA supply. In consideration that fish at higher water temperature

  11. Arachidonic Acid and Eicosapentaenoic Acid Metabolism in Juvenile Atlantic Salmon as Affected by Water Temperature

    PubMed Central

    Norambuena, Fernando; Morais, Sofia; Emery, James A.; Turchini, Giovanni M.

    2015-01-01

    Salmons raised in aquaculture farms around the world are increasingly subjected to sub-optimal environmental conditions, such as high water temperatures during summer seasons. Aerobic scope increases and lipid metabolism changes are known plasticity responses of fish for a better acclimation to high water temperature. The present study aimed at investigating the effect of high water temperature on the regulation of fatty acid metabolism in juvenile Atlantic salmon fed different dietary ARA/EPA ratios (arachidonic acid, 20:4n-6/ eicosapentaenoic acid, 20:5n-3), with particular focus on apparent in vivo enzyme activities and gene expression of lipid metabolism pathways. Three experimental diets were formulated to be identical, except for the ratio EPA/ARA, and fed to triplicate groups of Atlantic salmon (Salmo salar) kept either at 10°C or 20°C. Results showed that fatty acid metabolic utilisation, and likely also their dietary requirements for optimal performance, can be affected by changes in their relative levels and by environmental temperature in Atlantic salmon. Thus, the increase in temperature, independently from dietary treatment, had a significant effect on the β-oxidation of a fatty acid including EPA, as observed by the apparent in vivo enzyme activity and mRNA expression of pparα -transcription factor in lipid metabolism, including β-oxidation genes- and cpt1 -key enzyme responsible for the movement of LC-PUFA from the cytosol into the mitochondria for β-oxidation-, were both increased at the higher water temperature. An interesting interaction was observed in the transcription and in vivo enzyme activity of Δ5fad–time-limiting enzyme in the biosynthesis pathway of EPA and ARA. Such, at lower temperature, the highest mRNA expression and enzyme activity was recorded in fish with limited supply of dietary EPA, whereas at higher temperature these were recorded in fish with limited ARA supply. In consideration that fish at higher water temperature

  12. A Metabolic Probe-Enabled Strategy Reveals Uptake and Protein Targets of Polyunsaturated Aldehydes in the Diatom Phaeodactylum tricornutum.

    PubMed

    Wolfram, Stefanie; Wielsch, Natalie; Hupfer, Yvonne; Mönch, Bettina; Lu-Walther, Hui-Wen; Heintzmann, Rainer; Werz, Oliver; Svatoš, Aleš; Pohnert, Georg

    2015-01-01

    Diatoms are unicellular algae of crucial importance as they belong to the main primary producers in aquatic ecosystems. Several diatom species produce polyunsaturated aldehydes (PUAs) that have been made responsible for chemically mediated interactions in the plankton. PUA-effects include chemical defense by reducing the reproductive success of grazing copepods, allelochemical activity by interfering with the growth of competing phytoplankton and cell to cell signaling. We applied a PUA-derived molecular probe, based on the biologically highly active 2,4-decadienal, with the aim to reveal protein targets of PUAs and affected metabolic pathways. By using fluorescence microscopy, we observed a substantial uptake of the PUA probe into cells of the diatom Phaeodactylum tricornutum in comparison to the uptake of a structurally closely related control probe based on a saturated aldehyde. The specific uptake motivated a chemoproteomic approach to generate a qualitative inventory of proteins covalently targeted by the α,β,γ,δ-unsaturated aldehyde structure element. Activity-based protein profiling revealed selective covalent modification of target proteins by the PUA probe. Analysis of the labeled proteins gave insights into putative affected molecular functions and biological processes such as photosynthesis including ATP generation and catalytic activity in the Calvin cycle or the pentose phosphate pathway. The mechanism of action of PUAs involves covalent reactions with proteins that may result in protein dysfunction and interference of involved pathways.

  13. A Metabolic Probe-Enabled Strategy Reveals Uptake and Protein Targets of Polyunsaturated Aldehydes in the Diatom Phaeodactylum tricornutum

    PubMed Central

    Wolfram, Stefanie; Wielsch, Natalie; Hupfer, Yvonne; Mönch, Bettina; Lu-Walther, Hui-Wen; Heintzmann, Rainer; Werz, Oliver; Svatoš, Aleš; Pohnert, Georg

    2015-01-01

    Diatoms are unicellular algae of crucial importance as they belong to the main primary producers in aquatic ecosystems. Several diatom species produce polyunsaturated aldehydes (PUAs) that have been made responsible for chemically mediated interactions in the plankton. PUA-effects include chemical defense by reducing the reproductive success of grazing copepods, allelochemical activity by interfering with the growth of competing phytoplankton and cell to cell signaling. We applied a PUA-derived molecular probe, based on the biologically highly active 2,4-decadienal, with the aim to reveal protein targets of PUAs and affected metabolic pathways. By using fluorescence microscopy, we observed a substantial uptake of the PUA probe into cells of the diatom Phaeodactylum tricornutum in comparison to the uptake of a structurally closely related control probe based on a saturated aldehyde. The specific uptake motivated a chemoproteomic approach to generate a qualitative inventory of proteins covalently targeted by the α,β,γ,δ-unsaturated aldehyde structure element. Activity-based protein profiling revealed selective covalent modification of target proteins by the PUA probe. Analysis of the labeled proteins gave insights into putative affected molecular functions and biological processes such as photosynthesis including ATP generation and catalytic activity in the Calvin cycle or the pentose phosphate pathway. The mechanism of action of PUAs involves covalent reactions with proteins that may result in protein dysfunction and interference of involved pathways. PMID:26496085

  14. A Metabolic Probe-Enabled Strategy Reveals Uptake and Protein Targets of Polyunsaturated Aldehydes in the Diatom Phaeodactylum tricornutum.

    PubMed

    Wolfram, Stefanie; Wielsch, Natalie; Hupfer, Yvonne; Mönch, Bettina; Lu-Walther, Hui-Wen; Heintzmann, Rainer; Werz, Oliver; Svatoš, Aleš; Pohnert, Georg

    2015-01-01

    Diatoms are unicellular algae of crucial importance as they belong to the main primary producers in aquatic ecosystems. Several diatom species produce polyunsaturated aldehydes (PUAs) that have been made responsible for chemically mediated interactions in the plankton. PUA-effects include chemical defense by reducing the reproductive success of grazing copepods, allelochemical activity by interfering with the growth of competing phytoplankton and cell to cell signaling. We applied a PUA-derived molecular probe, based on the biologically highly active 2,4-decadienal, with the aim to reveal protein targets of PUAs and affected metabolic pathways. By using fluorescence microscopy, we observed a substantial uptake of the PUA probe into cells of the diatom Phaeodactylum tricornutum in comparison to the uptake of a structurally closely related control probe based on a saturated aldehyde. The specific uptake motivated a chemoproteomic approach to generate a qualitative inventory of proteins covalently targeted by the α,β,γ,δ-unsaturated aldehyde structure element. Activity-based protein profiling revealed selective covalent modification of target proteins by the PUA probe. Analysis of the labeled proteins gave insights into putative affected molecular functions and biological processes such as photosynthesis including ATP generation and catalytic activity in the Calvin cycle or the pentose phosphate pathway. The mechanism of action of PUAs involves covalent reactions with proteins that may result in protein dysfunction and interference of involved pathways. PMID:26496085

  15. Depletion of PINK1 affects mitochondrial metabolism, calcium homeostasis and energy maintenance.

    PubMed

    Heeman, Bavo; Van den Haute, Chris; Aelvoet, Sarah-Ann; Valsecchi, Federica; Rodenburg, Richard J; Reumers, Veerle; Debyser, Zeger; Callewaert, Geert; Koopman, Werner J H; Willems, Peter H G M; Baekelandt, Veerle

    2011-04-01

    Loss-of-function mutations in the gene encoding the mitochondrial PTEN-induced putative kinase 1 (PINK1) are a major cause of early-onset familial Parkinson's disease (PD). Recent studies have highlighted an important function for PINK1 in clearing depolarized mitochondria by mitophagy. However, the role of PINK1 in mitochondrial and cellular functioning in physiological conditions is still incompletely understood. Here, we investigate mitochondrial and cellular calcium (Ca(2+)) homeostasis in PINK1-knockdown and PINK1-knockout mouse cells, both in basal metabolic conditions and after physiological stimulation, using unbiased automated live single-cell imaging in combination with organelle-specific fluorescent probes. Our data reveal that depletion of PINK1 induces moderate fragmentation of the mitochondrial network, mitochondrial membrane depolarization and increased production of reactive oxygen species. This results in reduced uptake of Ca(2+) by mitochondria after physiological stimulation. As a consequence, cells with knockdown or knockout of PINK1 display impaired mitochondrial ATP synthesis, which is exacerbated under conditions of increased ATP demand, thereby affecting cytosolic Ca(2+) extrusion. The impairment in energy maintenance was confirmed in the brain of PINK1-knockout mice by in vivo bioluminescence imaging. Our findings demonstrate a key role for PINK1 in the regulation of mitochondrial homeostasis and energy metabolism under physiological conditions. PMID:21385841

  16. Incubation temperature affects growth and energy metabolism in blue tit nestlings.

    PubMed

    Nord, Andreas; Nilsson, Jan-Åke

    2011-11-01

    Because the maintenance of proper developmental temperatures during avian incubation is costly to parents, embryos of many species experience pronounced variation in incubation temperature. However, the effects of such temperature variation on nestling development remain relatively unexplored. To investigate this, we artificially incubated wild blue tit (Cyanistes caeruleus L.) clutches at 35.0°, 36.5°, or 38.0°C for two-thirds of the incubation period. We returned clutches to their original nests before hatching and subsequently recorded nestling growth and resting metabolic rate. The length of the incubation period decreased with temperature, whereas hatching success increased. Nestlings from the lowest incubation temperature group had shorter tarsus lengths at 2 weeks of age, but body mass and wing length were not affected by temperature. In addition, nestlings from the lowest temperature group had a significantly higher resting metabolic rate compared with mid- and high-temperature nestlings, which may partly explain observed size differences between the groups. These findings suggest that nest microclimate can influence nestling phenotype, but whether observed differences carry over to later life-history stages remains unknown.

  17. Campomanesia adamantium extract induces DNA damage, apoptosis, and affects cyclophosphamide metabolism.

    PubMed

    Martello, M D; David, N; Matuo, R; Carvalho, P C; Navarro, S D; Monreal, A C D; Cunha-Laura, A L; Cardoso, C A L; Kassuya, C A L; Oliveira, R J

    2016-01-01

    Campomanesia adamantium (Cambess.) O. Berg. is originally from Brazil. Its leaves and fruits have medicinal properties such as anti-inflammatory, antidiarrheal and antiseptic properties. However, the mutagenic potential of this species has been reported in few studies. This study describes the mutagenic/antimutagenic, splenic phagocytic, and apoptotic activities of C. adamantium hydroethanolic extract with or without cyclophosphamide in Swiss mice. The animals orally received the hydroethanolic extract at doses of 30, 100, or 300 mg/kg with or without 100 mg/kg cyclophosphamide. Mutagenesis was evaluated by performing the micronucleus assay after treatment for 24, 48, and 72 h, while splenic phagocytic and apoptotic effects were investigated after 72 h. Short-term exposure of 30 and 100 mg/kg extract induced mild clastogenic/aneugenic effects and increased splenic phagocytosis and apoptosis in the liver, spleen, and kidneys. When the extract was administered in combination with cyclophosphamide, micronucleus frequency and apoptosis reduced. Extract components might affect cyclophosphamide metabolism, which possibly leads to increased clearance of this chemotherapeutic agent. C. adamantium showed mutagenic activity and it may decrease the effectiveness of drugs with metabolic pathways similar to those associated with cyclophosphamide. Thus, caution should be exercised while consuming these extracts, especially when received in combination with other drugs. PMID:27173259

  18. Failure of caffeine to affect metabolism during 60 min submaximal exercise.

    PubMed

    Titlow, L W; Ishee, J H; Riggs, C E

    1991-01-01

    Caffeine consumption prior to athletic performance has become commonplace. The usual dosage is approximately 200 mg, a level of caffeine ingestion equivalent to two cups of brewed coffee. This study was designed to examine the effects of a common level of caffeine ingestion, specifically 200 mg, on metabolism during submaximal exercise performance in five males. The subjects performed two 60-min monitored treadmill workouts at 60% maximal heart rate during a 2-week period. The subjects were randomly assigned, double-blind to receive a caffeine or placebo capsule 60 min prior to exercise. Testing was performed in the afternoon following a midnight fast. Venous blood was withdrawn pre-exercise, every 15 min during the workout, and 10 min after recovery. Blood was analysed for free fatty acid, triglycerides, glucose, lactic acid, haemoglobin and haematocrit. The respiratory exchange ratio (R), perceived exertion (RPE) and oxygen uptake were measured every 4 min during exercise. An examination of the data with repeated-measures ANOVA revealed no significant differences between the two groups. Within the limitations of the study, it was concluded that 200 mg caffeine failed to affect metabolism during 60 min submaximal exercise.

  19. Testosterone affects hormone-sensitive lipase (HSL) activity and lipid metabolism in the left ventricle.

    PubMed

    Langfort, Jozef; Jagsz, Slawomir; Dobrzyn, Pawel; Brzezinska, Zofia; Klapcinska, Barbara; Galbo, Henrik; Gorski, Jan

    2010-09-01

    Fatty acids, which are the major cardiac fuel, are derived from lipid droplets stored in cardiomyocytes, among other sources. The heart expresses hormone-sensitive lipase (HSL), which regulates triglycerides (TG) breakdown, and the enzyme is under hormonal control. Evidence obtained from adipose tissue suggests that testosterone regulates HSL activity. To test whether this is also true in the heart, we measured HSL activity in the left ventricle of sedentary male rats that had been treated with testosterone supplementation or orchidectomy with or without testosterone substitution. Left ventricle HSL activity against TG was significantly elevated in intact rats supplemented with testosterone. HSL activity against both TG and diacylglyceride was reduced by orchidectomy, whereas testosterone replacement fully reversed this effect. Moreover, testosterone increased left ventricle free fatty acid levels, caused an inhibitory effect on carbohydrate metabolism in the heart, and elevated left ventricular phosphocreatine and ATP levels as compared to control rats. These data indicate that testosterone is involved in cardiac HSL activity regulation which, in turn, may affect cardiac lipid and carbohydrate metabolism.

  20. Campomanesia adamantium extract induces DNA damage, apoptosis, and affects cyclophosphamide metabolism.

    PubMed

    Martello, M D; David, N; Matuo, R; Carvalho, P C; Navarro, S D; Monreal, A C D; Cunha-Laura, A L; Cardoso, C A L; Kassuya, C A L; Oliveira, R J

    2016-04-26

    Campomanesia adamantium (Cambess.) O. Berg. is originally from Brazil. Its leaves and fruits have medicinal properties such as anti-inflammatory, antidiarrheal and antiseptic properties. However, the mutagenic potential of this species has been reported in few studies. This study describes the mutagenic/antimutagenic, splenic phagocytic, and apoptotic activities of C. adamantium hydroethanolic extract with or without cyclophosphamide in Swiss mice. The animals orally received the hydroethanolic extract at doses of 30, 100, or 300 mg/kg with or without 100 mg/kg cyclophosphamide. Mutagenesis was evaluated by performing the micronucleus assay after treatment for 24, 48, and 72 h, while splenic phagocytic and apoptotic effects were investigated after 72 h. Short-term exposure of 30 and 100 mg/kg extract induced mild clastogenic/aneugenic effects and increased splenic phagocytosis and apoptosis in the liver, spleen, and kidneys. When the extract was administered in combination with cyclophosphamide, micronucleus frequency and apoptosis reduced. Extract components might affect cyclophosphamide metabolism, which possibly leads to increased clearance of this chemotherapeutic agent. C. adamantium showed mutagenic activity and it may decrease the effectiveness of drugs with metabolic pathways similar to those associated with cyclophosphamide. Thus, caution should be exercised while consuming these extracts, especially when received in combination with other drugs.

  1. Failure of caffeine to affect metabolism during 60 min submaximal exercise.

    PubMed

    Titlow, L W; Ishee, J H; Riggs, C E

    1991-01-01

    Caffeine consumption prior to athletic performance has become commonplace. The usual dosage is approximately 200 mg, a level of caffeine ingestion equivalent to two cups of brewed coffee. This study was designed to examine the effects of a common level of caffeine ingestion, specifically 200 mg, on metabolism during submaximal exercise performance in five males. The subjects performed two 60-min monitored treadmill workouts at 60% maximal heart rate during a 2-week period. The subjects were randomly assigned, double-blind to receive a caffeine or placebo capsule 60 min prior to exercise. Testing was performed in the afternoon following a midnight fast. Venous blood was withdrawn pre-exercise, every 15 min during the workout, and 10 min after recovery. Blood was analysed for free fatty acid, triglycerides, glucose, lactic acid, haemoglobin and haematocrit. The respiratory exchange ratio (R), perceived exertion (RPE) and oxygen uptake were measured every 4 min during exercise. An examination of the data with repeated-measures ANOVA revealed no significant differences between the two groups. Within the limitations of the study, it was concluded that 200 mg caffeine failed to affect metabolism during 60 min submaximal exercise. PMID:1856908

  2. 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.

  3. Calcium-Vitamin D Co-supplementation Affects Metabolic Profiles, but not Pregnancy Outcomes, in Healthy Pregnant Women

    PubMed Central

    Asemi, Zatollah; Samimi, Mansooreh; Siavashani, Mehrnush Amiri; Mazloomi, Maryam; Tabassi, Zohreh; Karamali, Maryam; Jamilian, Mehri; Esmaillzadeh, Ahmad

    2016-01-01

    Background: Pregnancy is associated with unfavorable metabolic profile, which might in turn result in adverse pregnancy outcomes. The current study was designed to evaluate the effects of calcium plus Vitamin D administration on metabolic status and pregnancy outcomes in healthy pregnant women. Methods: This randomized double-blind placebo-controlled clinical trial was performed among 42 pregnant women aged 18–40 years who were at week 25 of gestation. Subjects were randomly allocated to consume either 500 mg calcium-200 IU cholecalciferol supplements (n = 21) or placebo (n = 21) for 9 weeks. Blood samples were obtained at the onset of the study and after 9-week trial to determine related markers. Post-delivery, the newborn's weight, length, and head circumference were measured during the first 24 h after birth. Results: Consumption of calcium-Vitamin D co-supplements resulted in a significant reduction of serum high-sensitivity C-reactive protein levels compared with placebo (−1856.8 ± 2657.7 vs. 707.1 ± 3139.4 μg/mL, P = 0.006). We also found a significant elevation of plasma total antioxidant capacity (89.3 ± 118.0 vs. −9.4 ± 164.9 mmol/L, P = 0.03), serum 25-hydroxyvitamin D (2.5 ± 3.5 vs. −1.7 ± 1.7 ng/mL, P < 0.0001), and calcium levels (0.6 ± 0.6 vs. −0.1 ± 0.4 mg/dL, P < 0.0001). The supplementation led to a significant decrease in diastolic blood pressure (−1.9 ± 8.3 vs. 3.1 ± 5.2 mmHg, P = 0.02) compared with placebo. No significant effect of calcium-Vitamin D co-supplements was seen on other metabolic profiles. We saw no significant change of the co-supplementation on pregnancy outcomes as well. Conclusions: Although calcium-Vitamin D co-supplementation for 9 weeks in pregnant women resulted in improved metabolic profiles, it did not affect pregnancy outcomes. PMID:27076887

  4. Cre-mediated stress affects sirtuin expression levels, peroxisome biogenesis and metabolism, antioxidant and proinflammatory signaling pathways.

    PubMed

    Xiao, Yu; Karnati, Srikanth; Qian, Guofeng; Nenicu, Anca; Fan, Wei; Tchatalbachev, Svetlin; Höland, Anita; Hossain, Hamid; Guillou, Florian; Lüers, Georg H; Baumgart-Vogt, Eveline

    2012-01-01

    Cre-mediated excision of loxP sites is widely used in mice to manipulate gene function in a tissue-specific manner. To analyze phenotypic alterations related to Cre-expression, we have used AMH-Cre-transgenic mice as a model system. Different Cre expression levels were obtained by investigation of C57BL/6J wild type as well as heterozygous and homozygous AMH-Cre-mice. Our results indicate that Cre-expression itself in Sertoli cells already has led to oxidative stress and lipid peroxidation (4-HNE lysine adducts), inducing PPARα/γ, peroxisome proliferation and alterations of peroxisome biogenesis (PEX5, PEX13 and PEX14) as well as metabolic proteins (ABCD1, ABCD3, MFP1, thiolase B, catalase). In addition to the strong catalase increase, a NRF2- and FOXO3-mediated antioxidative response (HMOX1 of the endoplasmic reticulum and mitochondrial SOD2) and a NF-κB activation were noted. TGFβ1 and proinflammatory cytokines like IL1, IL6 and TNFα were upregulated and stress-related signaling pathways were induced. Sertoli cell mRNA-microarray analysis revealed an increase of TNFR2-signaling components. 53BP1 recruitment and expression levels for DNA repair genes as well as for p53 were elevated and the ones for related sirtuin deacetylases affected (SIRT 1, 3-7) in Sertoli cells. Under chronic Cre-mediated DNA damage conditions a strong downregulation of Sirt1 was observed, suggesting that the decrease of this important coordinator between DNA repair and metabolic signaling might induce the repression release of major transcription factors regulating metabolic and cytokine-mediated stress pathways. Indeed, caspase-3 was activated and increased germ cell apoptosis was observed, suggesting paracrine effects. In conclusion, the observed wide stress-induced effects and metabolic alterations suggest that it is essential to use the correct control animals (Cre/Wt) with matched Cre expression levels to differentiate between Cre-mediated and specific gene-knock out

  5. Factors Affecting the Absorption, Metabolism, and Excretion of Cocoa Flavanols in Humans.

    PubMed

    Cifuentes-Gomez, Tania; Rodriguez-Mateos, Ana; Gonzalez-Salvador, Isidro; Alañon, María Elena; Spencer, Jeremy P E

    2015-09-01

    Cocoa is rich in a subclass of flavonoids known as flavanols, the cardiovascular health benefits of which have been extensively reported. The appearance of flavanol metabolites in the systemic circulation after flavanol-rich food consumption is likely to mediate the physiological effects on the vascular system, and these levels are influenced by numerous factors, including food matrix, processing, intake, age, gender, or genetic polymorphisms, among others. This review will focus on our current understanding of factors affecting the absorption, metabolism, and excretion of cocoa flavanols in humans. Second, it will identify gaps in these contributing factors that need to be addressed to conclusively translate our collective knowledge into the context of public health, dietary guidelines, and evidence-based dietary recommendations.

  6. A palatable hyperlipidic diet causes obesity and affects brain glucose metabolism in rats

    PubMed Central

    2011-01-01

    Background We have previously shown that either the continuous intake of a palatable hyperlipidic diet (H) or the alternation of chow (C) and an H diet (CH regimen) induced obesity in rats. Here, we investigated whether the time of the start and duration of these feeding regimens are relevant and whether they affect brain glucose metabolism. Methods Male Wistar rats received C, H, or CH diets during various periods of their life spans: days 30-60, days 30-90, or days 60-90. Experiments were performed the 60th or the 90th day of life. Rats were killed by decapitation. The glucose, insulin, leptin plasma concentration, and lipid content of the carcasses were determined. The brain was sliced and incubated with or without insulin for the analysis of glucose uptake, oxidation, and the conversion of [1-14C]-glucose to lipids. Results The relative carcass lipid content increased in all of the H and CH groups, and the H30-60 and H30-90 groups had the highest levels. Groups H30-60, H30-90, CH30-60, and CH30-90 exhibited a higher serum glucose level. Serum leptin increased in all H groups and in the CH60-90 and CH30-90 groups. Serum insulin was elevated in the H30-60, H60-90, CH60-90, CH30-90 groups. Basal brain glucose consumption and hypothalamic insulin receptor density were lower only in the CH30-60 group. The rate of brain lipogenesis was increased in the H30-90 and CH30-90 groups. Conclusion These findings indicate that both H and CH diet regimens increased body adiposity independent treatment and the age at which treatment was started, whereas these diets caused hyperglycemia and affected brain metabolism when started at an early age. PMID:21943199

  7. A novel family of small proteins that affect plant development

    SciTech Connect

    John Charles Walker

    2011-04-29

    The DVL genes represent a new group of plant proteins that influence plant growth and development. Overexpression of DVL1, and other members of the DVL family, causes striking phenotypic changes. The DVL proteins share sequence homology in their C-terminal half. Point mutations in the C-terminal domain show it is necessary and deletion studies demonstrate the C-terminal domain is sufficient to confer the overexpression phenotypes. The phenotypes observed, and the conservation of the protein sequence in the plant kingdom, does suggest the DVL proteins have a role in modulating plant growth and development. Our working hypothesis is the DVL proteins function as regulators of cellular signaling pathways that control growth and development.

  8. FfVel1 and FfLae1, components of a velvet-like complex in Fusarium fujikuroi, affect differentiation, secondary metabolism and virulence

    PubMed Central

    Wiemann, Philipp; Brown, Daren W.; Kleigrewe, Karin; Bok, Jin Woo; Keller, Nancy P.; Humpf, Hans-Ulrich; Tudzynski, Bettina

    2010-01-01

    Summary Besides industrially produced gibberellins (GAs), Fusarium fujikuroi is able to produce additional secondary metabolites such as the pigments bikaverin and neurosporaxanthin and the mycotoxins fumonisins and fusarin C. The global regulation of these biosynthetic pathways is only poorly understood. Recently, the velvet complex containing VeA and several other regulatory proteins was shown to be involved in global regulation of secondary metabolism and differentiation in Aspergillus nidulans. Here we report on the characterization of two components of the F. fujikuroi velvet-like complex, FfVel1 and FfLae1. The gene encoding this first reported LaeA ortholog outside the class of Eurotiomycetidae is upregulated in ΔFfvel1 microarray-studies and FfLae1 interacts with FfVel1 in the nucleus. Deletion of Ffvel1 and Fflae1 revealed for the first time that velvet can simultaneously act as positive (GAs, fumonisins and fusarin C) and negative (bikaverin) regulator of secondary metabolism, and that both components affect conidiation and virulence of F. fujikuroi. Furthermore, the velvet-like protein FfVel2 revealed similar functions regarding conidiation, secondary metabolism and virulence as FfVel1. Cross genus complementation studies of velvet complex component mutants between Fusarium, Aspergillus and Penicillium support an ancient origin for this complex which has undergone a divergence in specific functions mediating development and secondary metabolism. PMID:20572938

  9. Approaches to Optimizing Animal Cell Culture Process: Substrate Metabolism Regulation and Protein Expression Improvement

    NASA Astrophysics Data System (ADS)

    Zhang, Yuanxing

    Some high value proteins and vaccines for medical and veterinary applications by animal cell culture have an increasing market in China. In order to meet the demands of large-scale productions of proteins and vaccines, animal cell culture technology has been widely developed. In general, an animal cell culture process can be divided into two stages in a batch culture. In cell growth stage a high specific growth rate is expected to achieve a high cell density. In production stage a high specific production rate is stressed for the expression and secretion of qualified protein or replication of virus. It is always critical to maintain high cell viability in fed-batch and perfusion cultures. More concern has been focused on two points by the researchers in China. First, the cell metabolism of substrates is analyzed and the accumulation of toxic by-products is decreased through regulating cell metabolism in the culture process. Second, some important factors effecting protein expression are understood at the molecular level and the production ability of protein is improved. In pace with the rapid development of large-scale cell culture for the production of vaccines, antibodies and other recombinant proteins in China, the medium design and process optimization based on cell metabolism regulation and protein expression improvement will play an important role. The chapter outlines the main advances in metabolic regulation of cell and expression improvement of protein in animal cell culture in recent years.

  10. Glutamate availability is important in intramuscular amino acid metabolism and TCA cycle intermediates but does not affect peak oxidative metabolism.

    PubMed

    Mourtzakis, M; Graham, T E; González-Alonso, J; Saltin, B

    2008-08-01

    Muscle glutamate is central to reactions producing 2-oxoglutarate, a tricarboxylic acid (TCA) cycle intermediate that essentially expands the TCA cycle intermediate pool during exercise. Paradoxically, muscle glutamate drops approximately 40-80% with the onset of exercise and 2-oxoglutarate declines in early exercise. To investigate the physiological relationship between glutamate, oxidative metabolism, and TCA cycle intermediates (i.e., fumarate, malate, 2-oxoglutarate), healthy subjects trained (T) the quadriceps of one thigh on the single-legged knee extensor ergometer (1 h/day at 70% maximum workload for 5 days/wk), while their contralateral quadriceps remained untrained (UT). After 5 wk of training, peak oxygen consumption (VO2peak) in the T thigh was greater than that in the UT thigh (P<0.05); VO2peak was not different between the T and UT thighs with glutamate infusion. Peak exercise under control conditions revealed a greater glutamate uptake in the T thigh compared with rest (7.3+/-3.7 vs. 1.0+/-0.1 micromol.min(-1).kg wet wt(-1), P<0.05) without increase in TCA cycle intermediates. In the UT thigh, peak exercise (vs. rest) induced an increase in fumarate (0.33+/-0.07 vs. 0.02+/-0.01 mmol/kg dry wt (dw), P<0.05) and malate (2.2+/-0.4 vs. 0.5+/-0.03 mmol/kg dw, P<0.05) and a decrease in 2-oxoglutarate (12.2+/-1.6 vs. 32.4+/-6.8 micromol/kg dw, P<0.05). Overall, glutamate infusion increased arterial glutamate (P<0.05) and maintained this increase. Glutamate infusion coincided with elevated fumarate and malate (P<0.05) and decreased 2-oxoglutarate (P<0.05) at peak exercise relative to rest in the T thigh; there were no further changes in the UT thigh. Although glutamate may have a role in the expansion of the TCA cycle, glutamate and TCA cycle intermediates do not directly affect VO2peak in either trained or untrained muscle.

  11. Bt proteins Cry1Ah and Cry2Ab do not affect cotton aphid Aphis gossypii and ladybeetle Propylea japonica

    PubMed Central

    Zhao, Yao; Zhang, Shuai; Luo, Jun-Yu; Wang, Chun-Yi; Lv, Li-Min; Wang, Xiao-Ping; Cui, Jin-Jie; Lei, Chao-Liang

    2016-01-01

    Plant varieties expressing the Bt (Bacillus thuringiensis) insecticidal proteins Cry1Ah and Cry2Ab have potential commercialization prospects in China. However, their potential effects on non-target arthropods (NTAs) remain uncharacterized. The cotton aphid Aphis gossypii is a worldwide pest that damages various important crops. The ladybeetle Propylea japonica is a common and abundant natural enemy in many cropping systems in East Asia. In the present study, the effects of Cry1Ah and Cry2Ab proteins on A. gossypii and P. japonica were assessed from three aspects. First, neither of the Cry proteins affected the growth or developmental characteristics of the two test insects. Second, the expression levels of the detoxification-related genes of the two test insects did not change significantly in either Cry protein treatment. Third, neither of the Cry proteins had a favourable effect on the expression of genes associated with the amino acid metabolism of A. gossypii and the nutrition utilization of P. japonica. In conclusion, the Cry1Ah and Cry2Ab proteins do not appear to affect the cotton aphid A. gossypii or the ladybeetle P. japonica. PMID:26829252

  12. Evaluation of energy metabolism and calcium homeostasis in cells affected by Shwachman-Diamond syndrome.

    PubMed

    Ravera, Silvia; Dufour, Carlo; Cesaro, Simone; Bottega, Roberta; Faleschini, Michela; Cuccarolo, Paola; Corsolini, Fabio; Usai, Cesare; Columbaro, Marta; Cipolli, Marco; Savoia, Anna; Degan, Paolo; Cappelli, Enrico

    2016-01-01

    Isomorphic mutation of the SBDS gene causes Shwachman-Diamond syndrome (SDS). SDS is a rare genetic bone marrow failure and cancer predisposition syndrome. SDS cells have ribosome biogenesis and their protein synthesis altered, which are two high-energy consuming cellular processes. The reported changes in reactive oxygen species production, endoplasmic reticulum stress response and reduced mitochondrial functionality suggest an energy production defect in SDS cells. In our work, we have demonstrated that SDS cells display a Complex IV activity impairment, which causes an oxidative phosphorylation metabolism defect, with a consequent decrease in ATP production. These data were confirmed by an increased glycolytic rate, which compensated for the energetic stress. Moreover, the signalling pathways involved in glycolysis activation also appeared more activated; i.e. we reported AMP-activated protein kinase hyper-phosphorylation. Notably, we also observed an increase in a mammalian target of rapamycin phosphorylation and high intracellular calcium concentration levels ([Ca(2+)]i), which probably represent new biochemical equilibrium modulation in SDS cells. Finally, the SDS cell response to leucine (Leu) was investigated, suggesting its possible use as a therapeutic adjuvant to be tested in clinical trials. PMID:27146429

  13. Evaluation of energy metabolism and calcium homeostasis in cells affected by Shwachman-Diamond syndrome

    PubMed Central

    Ravera, Silvia; Dufour, Carlo; Cesaro, Simone; Bottega, Roberta; Faleschini, Michela; Cuccarolo, Paola; Corsolini, Fabio; Usai, Cesare; Columbaro, Marta; Cipolli, Marco; Savoia, Anna; Degan, Paolo; Cappelli, Enrico

    2016-01-01

    Isomorphic mutation of the SBDS gene causes Shwachman-Diamond syndrome (SDS). SDS is a rare genetic bone marrow failure and cancer predisposition syndrome. SDS cells have ribosome biogenesis and their protein synthesis altered, which are two high-energy consuming cellular processes. The reported changes in reactive oxygen species production, endoplasmic reticulum stress response and reduced mitochondrial functionality suggest an energy production defect in SDS cells. In our work, we have demonstrated that SDS cells display a Complex IV activity impairment, which causes an oxidative phosphorylation metabolism defect, with a consequent decrease in ATP production. These data were confirmed by an increased glycolytic rate, which compensated for the energetic stress. Moreover, the signalling pathways involved in glycolysis activation also appeared more activated; i.e. we reported AMP-activated protein kinase hyper-phosphorylation. Notably, we also observed an increase in a mammalian target of rapamycin phosphorylation and high intracellular calcium concentration levels ([Ca2+]i), which probably represent new biochemical equilibrium modulation in SDS cells. Finally, the SDS cell response to leucine (Leu) was investigated, suggesting its possible use as a therapeutic adjuvant to be tested in clinical trials. PMID:27146429

  14. Exposure to gemfibrozil and atorvastatin affects cholesterol metabolism and steroid production in zebrafish (Danio rerio).

    PubMed

    Al-Habsi, Aziz A; Massarsky, Andrey; Moon, Thomas W

    2016-09-01

    The commonly used lipid-lowering pharmaceuticals gemfibrozil (GEM) and atorvastatin (ATV) are detected in the aquatic environment; however, their potential effects on non-target fish species are yet to be fully understood. This study examined the effects of GEM and/or ATV on female and male adult zebrafish after a 30d dietary exposure. The exposure led to changes in several biochemical parameters, including reduction in cholesterol, triglycerides, cortisol, testosterone, and estradiol. Changes in cholesterol and triglycerides were also associated with changes in transcript levels of key genes involved with cholesterol and lipid regulation, including SREBP2, HMGCR1, PPARα, and SREBP1. We also noted higher CYP3A65 and atrogin1 mRNA levels in drug-treated male fish. Sex differences were apparent in some of the examined parameters at both biochemical and molecular levels. This study supports these drugs affecting cholesterol metabolism and steroid production in adult zebrafish. We conclude that the reduction in cortisol may impair the ability of these fish to mount a suitable stress response, whereas the reduction of sex steroids may negatively affect reproduction. PMID:26627126

  15. Diet affects resting, but not basal metabolic rate of normothermic Siberian hamsters acclimated to winter.

    PubMed

    Gutowski, Jakub P; Wojciechowski, Michał S; Jefimow, Małgorzata

    2011-12-01

    We examined the effect of different dietary supplements on seasonal changes in body mass (m(b)), metabolic rate (MR) and nonshivering thermogenesis (NST) capacity in normothermic Siberian hamsters housed under semi-natural conditions. Once a week standard hamster food was supplemented with either sunflower and flax seeds, rich in polyunsaturated fatty acids (FA), or mealworms, rich in saturated and monounsaturated FA. We found that neither of these dietary supplements affected the hamsters' normal winter decrease in m(b) and fat content nor their basal MR or NST capacity. NST capacity of summer-acclimated hamsters was lower than that of winter-acclimated ones. The composition of total body fat reflected the fat composition of the dietary supplements. Resting MR below the lower critical temperature of the hamsters, and their total serum cholesterol concentration were lower in hamsters fed a diet supplemented with mealworms than in hamsters fed a diet supplemented with seeds. These results indicate that in mealworm-fed hamsters energy expenditure in the cold is lower than in animals eating a seed-supplemented diet, and that the degree of FA unsaturation of diet affects energetics of heterotherms, not only during torpor, but also during normothermy.

  16. Exposure to gemfibrozil and atorvastatin affects cholesterol metabolism and steroid production in zebrafish (Danio rerio).

    PubMed

    Al-Habsi, Aziz A; Massarsky, Andrey; Moon, Thomas W

    2016-09-01

    The commonly used lipid-lowering pharmaceuticals gemfibrozil (GEM) and atorvastatin (ATV) are detected in the aquatic environment; however, their potential effects on non-target fish species are yet to be fully understood. This study examined the effects of GEM and/or ATV on female and male adult zebrafish after a 30d dietary exposure. The exposure led to changes in several biochemical parameters, including reduction in cholesterol, triglycerides, cortisol, testosterone, and estradiol. Changes in cholesterol and triglycerides were also associated with changes in transcript levels of key genes involved with cholesterol and lipid regulation, including SREBP2, HMGCR1, PPARα, and SREBP1. We also noted higher CYP3A65 and atrogin1 mRNA levels in drug-treated male fish. Sex differences were apparent in some of the examined parameters at both biochemical and molecular levels. This study supports these drugs affecting cholesterol metabolism and steroid production in adult zebrafish. We conclude that the reduction in cortisol may impair the ability of these fish to mount a suitable stress response, whereas the reduction of sex steroids may negatively affect reproduction.

  17. Effect of chronic stress on behavior and cerebral oxidative metabolism in rats with high or low positive affect.

    PubMed

    Mällo, T; Matrov, D; Kõiv, K; Harro, J

    2009-12-15

    The 50 kHz ultrasonic vocalizations (USVs) in rats have been associated with positive affect and rewarding experience. We have previously reported that stable inter-individual differences exist in the expression of these USVs (chirps). We have examined the effect of four weeks of chronic variable stress on cerebral oxidative metabolism, and depression and anxiety related behavior in male and female high (HC) and low (LC) chirping rats. Significant differences in regional oxidative metabolic activity as measured by cytochrome c oxidase (COX) histochemistry were found between male and female rats: Females had lower oxidative metabolism in several brainstem areas such as dorsal and median raphe and pontine nucleus, some cortical areas, and reward-related forebrain regions such as striatum and nucleus accumbens, but higher oxidative metabolism in amygdala and related limbic regions. Chronic stress increased oxidative metabolism in several depression-related brain regions in male but not female LC-rats such as amygdala, hippocampus and anterior thalamus. No systematic behavioral effect of stress was evident in females. In LC males, stress elicited increased levels of 22-kHz USVs, earlier and more stable reduction of weight gain, persistently lower sucrose intake and preference, and higher levels of immobility in the forced swimming test. These behavioral changes, accompanied by increased oxidative metabolism in limbic brain regions, indicate greater vulnerability to stress of male LC-rats, and suggest that in males low inherent positive affectivity predisposes to anxiety and affective disorders.

  18. Self-selected unrefined and refined carbohydrate diets do not affect metabolic control in pump-treated diabetic patients.

    PubMed

    Venhaus, A; Chantelau, E

    1988-03-01

    This study investigated whether unrefined or refined carbohydrate diets have any effect on metabolic control and on insulin requirement in near-normoglycaemic Type 1 (insulin-dependent) diabetic out-patients on continuous subcutaneous insulin infusion therapy. Two females and 8 males (aged 27 +/- 9 years; diabetes duration 13 +/- 8 years; duration of insulin pump therapy 22 +/- 5 months; means +/- SD) participated in a randomised cross-over study with two 6-week periods on self-selected refined and unrefined carbohydrate diets respectively. As a result, energy intake differed between the experimental diets (2372 +/- 669 kcal/day on unrefined diet vs 2757 +/- 654 kcal/day on refined diet, p = 0.04), as did the fibre intake (18 +/- 5 g/day with the refined carbohydrate diet vs 35 +/- 13 g/day with the unrefined carbohydrate diet, p = 0.02). The composition of nutrients was approximately 40% carbohydrate, 45% fat, and 13% protein with both diets. Body weight, HbA1c, daily mean blood glucose (7.2 +/- 0.6 mmol/l) and serum lipids remained virtually unchanged during the entire study. Insulin requirement varied between 40.1 +/- 7.9 U/day with the unrefined carbohydrate diet, and 42.5 +/- 10.1 U/day with the refined carbohydrate diet (NS). Thus, neither the refined nor the unrefined carbohydrate diet affected insulin requirement and metabolic control in these near-normoglycaemic, normolipaemic, non-obese, insulin-pump-treated Type 1 diabetic patients.

  19. CELLULAR MECHANISMS OF PROTEIN METABOLISM IN THE NEPHRON

    PubMed Central

    Oliver, Jean; MacDowell, Muriel

    1958-01-01

    1. The exaggeration of "hyaline droplet" formation observed in the renal lesion of epidemic hemorrhagic fever when treated with the infusion of large amounts of human serum albumin and the histochemical characteristics of the droplets so formed afford evidence towards their identification with the protein absorption droplets of experimental procedures and with those that occur in other renal diseases. 2. Protein absorption droplets (hyaline droplets) are the visible aspect of pathological modifications of a physiological process; i.e., the continuing reabsorption of plasma proteins by the proximal convolutions. 3. The mitochondria of the renal cells are directly involved in both the physiological and the abnormal reabsorption and disposal of the plasma proteins; the absorption droplets are a complex of reabsorbed proteins and mitochondrial substances and enzymes; they result whenever disposal is at a rate insufficient to prevent accumulation. 4. Failure of intracellular disposal of reabsorbed protein is determined by (a) the quantitative and qualitative characteristics of the protein and (b) by the functional state of renal cell. 5. Various factors in renal disease that result in disturbances of reabsorption and of intracellular disposal, both with and without droplet formation, are described. PMID:13525582

  20. Labeling Cell Surface GPIs and GPI-Anchored Proteins through Metabolic Engineering with Artificial Inositol Derivatives.

    PubMed

    Lu, Lili; Gao, Jian; Guo, Zhongwu

    2015-08-10

    Glycosylphosphatidylinositol (GPI) anchoring of proteins to the cell surface is important for various biological processes, but GPI-anchored proteins are difficult to study. An effective strategy was developed for the metabolic engineering of cell-surface GPIs and GPI-anchored proteins by using inositol derivatives carrying an azido group. The azide-labeled GPIs and GPI-anchored proteins were then tagged with biotin on live cells through a click reaction, which allows further elaboration with streptavidin-conjugated dyes or other molecules. The strategy can be used to label GPI-anchored proteins with various tags for biological studies.

  1. Xenobiotic-contaminated diets affect hepatic lipid metabolism: Implications for liver steatosis in Sparus aurata juveniles.

    PubMed

    Maradonna, F; Nozzi, V; Santangeli, S; Traversi, I; Gallo, P; Fattore, E; Mita, D G; Mandich, A; Carnevali, O

    2015-10-01

    The metabolic effects induced by feed contaminated with a lower or a higher concentration of -nonylpnenol (NP), 4-tert-octylphenol (t-OP) or bisphenol A (BPA), three environmental endocrine disruptors, were assessed in juvenile sea bream liver. Histological analysis demonstrated that all these three xenobiotics induced hepatic lipid accumulation and steatosis. These findings prompted analysis of the expression of the major molecules involved in lipid metabolism: peroxisome proliferator activated receptors (which is encoded by ppars), fatty acid synthase (encoded by fas), lipoprotein lipase (encoded by lpl) and hormone-sensitive lipase (encoded by hsl). The enzymes encoded by ppars and fas are in fact responsible for lipid accumulation, whereas lpl- and hsl- encoded proteins play a pivotal role in fat mobilization. The three xenobiotics modulated ppar mRNA expression: pparα mRNA expression was induced by the higher dose of each contaminant; pparβ mRNA expression was upregulated by the lower doses and in BPA2 fish ppary mRNA overexpression was induced by all pollutants. These data agreed with the lipid accumulation profiles documented by histology. Fas mRNA levels were modulated by the two NP doses and the higher BPA concentration. Lpl mRNA was significantly upregulated in all experimental groups except for BPA1 fish while hsl mRNA was significantly downregulated in all groups except for t-OP2 and BPA1 fish. The plasma concentrations of cortisol, the primary stress biomarker, were correlated with the levels of pepck mRNA level. This gene encodes phosphoenolpyruvate carboxykinase which is one of the key enzymes of gluconeogenesis. Pepck mRNA was significantly overexpressed in fish exposed to NP2 and both t-OP doses. Finally, the genes encoding cyclooxygenase 2 (cox2) and 5-lipoxygenase (5 lox), the products of which are involved in the inflammatory response, transcriptions were significantly upregulated in NP and BPA fish, whereas they were unchanged in t

  2. Xenobiotic-contaminated diets affect hepatic lipid metabolism: Implications for liver steatosis in Sparus aurata juveniles.

    PubMed

    Maradonna, F; Nozzi, V; Santangeli, S; Traversi, I; Gallo, P; Fattore, E; Mita, D G; Mandich, A; Carnevali, O

    2015-10-01

    The metabolic effects induced by feed contaminated with a lower or a higher concentration of -nonylpnenol (NP), 4-tert-octylphenol (t-OP) or bisphenol A (BPA), three environmental endocrine disruptors, were assessed in juvenile sea bream liver. Histological analysis demonstrated that all these three xenobiotics induced hepatic lipid accumulation and steatosis. These findings prompted analysis of the expression of the major molecules involved in lipid metabolism: peroxisome proliferator activated receptors (which is encoded by ppars), fatty acid synthase (encoded by fas), lipoprotein lipase (encoded by lpl) and hormone-sensitive lipase (encoded by hsl). The enzymes encoded by ppars and fas are in fact responsible for lipid accumulation, whereas lpl- and hsl- encoded proteins play a pivotal role in fat mobilization. The three xenobiotics modulated ppar mRNA expression: pparα mRNA expression was induced by the higher dose of each contaminant; pparβ mRNA expression was upregulated by the lower doses and in BPA2 fish ppary mRNA overexpression was induced by all pollutants. These data agreed with the lipid accumulation profiles documented by histology. Fas mRNA levels were modulated by the two NP doses and the higher BPA concentration. Lpl mRNA was significantly upregulated in all experimental groups except for BPA1 fish while hsl mRNA was significantly downregulated in all groups except for t-OP2 and BPA1 fish. The plasma concentrations of cortisol, the primary stress biomarker, were correlated with the levels of pepck mRNA level. This gene encodes phosphoenolpyruvate carboxykinase which is one of the key enzymes of gluconeogenesis. Pepck mRNA was significantly overexpressed in fish exposed to NP2 and both t-OP doses. Finally, the genes encoding cyclooxygenase 2 (cox2) and 5-lipoxygenase (5 lox), the products of which are involved in the inflammatory response, transcriptions were significantly upregulated in NP and BPA fish, whereas they were unchanged in t

  3. Proteins involved in flor yeast carbon metabolism under biofilm formation conditions.

    PubMed

    Moreno-García, Jaime; García-Martínez, Teresa; Moreno, Juan; Mauricio, Juan Carlos

    2015-04-01

    A lack of sugars during the production of biologically aged wines after fermentation of grape must causes flor yeasts to metabolize other carbon molecules formed during fermentation (ethanol and glycerol, mainly). In this work, a proteome analysis involving OFFGEL fractionation prior to LC/MS detection was used to elucidate the carbon metabolism of a flor yeast strain under biofilm formation conditions (BFC). The results were compared with those obtained under non-biofilm formation conditions (NBFC). Proteins associated to processes such as non-fermentable carbon uptake, the glyoxylate and TCA cycles, cellular respiration and inositol metabolism were detected at higher concentrations under BFC than under the reference conditions (NBFC). This study constitutes the first attempt at identifying the flor yeast proteins responsible for the peculiar sensory profile of biologically aged wines. A better metabolic knowledge of flor yeasts might facilitate the development of effective strategies for improved production of these special wines.

  4. Proteins involved in flor yeast carbon metabolism under biofilm formation conditions.

    PubMed

    Moreno-García, Jaime; García-Martínez, Teresa; Moreno, Juan; Mauricio, Juan Carlos

    2015-04-01

    A lack of sugars during the production of biologically aged wines after fermentation of grape must causes flor yeasts to metabolize other carbon molecules formed during fermentation (ethanol and glycerol, mainly). In this work, a proteome analysis involving OFFGEL fractionation prior to LC/MS detection was used to elucidate the carbon metabolism of a flor yeast strain under biofilm formation conditions (BFC). The results were compared with those obtained under non-biofilm formation conditions (NBFC). Proteins associated to processes such as non-fermentable carbon uptake, the glyoxylate and TCA cycles, cellular respiration and inositol metabolism were detected at higher concentrations under BFC than under the reference conditions (NBFC). This study constitutes the first attempt at identifying the flor yeast proteins responsible for the peculiar sensory profile of biologically aged wines. A better metabolic knowledge of flor yeasts might facilitate the development of effective strategies for improved production of these special wines. PMID:25475262

  5. Translocator Protein (TSPO) Affects Mitochondrial Fatty Acid Oxidation in Steroidogenic Cells.

    PubMed

    Tu, Lan N; Zhao, Amy H; Hussein, Mahmoud; Stocco, Douglas M; Selvaraj, Vimal

    2016-03-01

    Translocator protein (TSPO), also known as the peripheral benzodiazepine receptor, is a highly conserved outer mitochondrial membrane protein present in specific subpopulations of cells within different tissues. In recent studies, the presumptive model depicting mammalian TSPO as a critical cholesterol transporter for steroidogenesis has been refuted by studies examining effects of Tspo gene deletion in vivo and in vitro, biochemical testing of TSPO cholesterol transport function, and specificity of TSPO-mediated pharmacological responses. Nevertheless, high TSPO expression in steroid-producing cells seemed to indicate an alternate function for this protein in steroidogenic mitochondria. To seek an explanation, we used CRISPR/Cas9-mediated TSPO knockout steroidogenic MA-10 Leydig cell (MA-10:TspoΔ/Δ) clones to examine changes to core mitochondrial functions resulting from TSPO deficiency. We observed that 1) MA-10:TspoΔ/Δ cells had a shift in substrate utilization for energy production from glucose to fatty acids with significantly higher mitochondrial fatty acid oxidation (FAO), and increased reactive oxygen species production; and 2) oxygen consumption rate, mitochondrial membrane potential, and proton leak were not different between MA-10:TspoΔ/Δ and MA-10:Tspo+/+ control cells. Consistent with this finding, TSPO-deficient adrenal glands from global TSPO knockout (Tspo(-/-)) mice also showed up-regulation of genes involved in FAO compared with the TSPO floxed (Tspo(fl/fl)) controls. These results demonstrate the first experimental evidence that TSPO can affect mitochondrial energy homeostasis through modulation of FAO, a function that appears to be consistent with high levels of TSPO expression observed in cell types active in lipid storage/metabolism.

  6. Myocardial oxidative metabolism and protein synthesis during mechanical circulatory support by extracorporeal membrane oxygenation.

    PubMed

    Priddy, Colleen M O'Kelly; Kajimoto, Masaki; Ledee, Dolena R; Bouchard, Bertrand; Isern, Nancy; Olson, Aaron K; Des Rosiers, Christine; Portman, Michael A

    2013-02-01

    Extracorporeal membrane oxygenation (ECMO) provides essential mechanical circulatory support necessary for survival in infants and children with acute cardiac decompensation. However, ECMO also causes metabolic disturbances, which contribute to total body wasting and protein loss. Cardiac stunning can also occur, which prevents ECMO weaning, and contributes to high mortality. The heart may specifically undergo metabolic impairments, which influence functional recovery. We tested the hypothesis that ECMO alters oxidative metabolism and protein synthesis. We focused on the amino acid leucine and integration with myocardial protein synthesis. We used a translational immature swine model in which we assessed in heart 1) the fractional contribution of leucine (FcLeucine) and pyruvate to mitochondrial acetyl-CoA formation by nuclear magnetic resonance and 2) global protein fractional synthesis (FSR) by gas chromatography-mass spectrometry. Immature mixed breed Yorkshire male piglets (n = 22) were divided into four groups based on loading status (8 h of normal circulation or ECMO) and intracoronary infusion [(13)C(6),(15)N]-L-leucine (3.7 mM) alone or with [2-(13)C]-pyruvate (7.4 mM). ECMO decreased pulse pressure and correspondingly lowered myocardial oxygen consumption (∼40%, n = 5), indicating decreased overall mitochondrial oxidative metabolism. However, FcLeucine was maintained and myocardial protein FSR was marginally increased. Pyruvate addition decreased tissue leucine enrichment, FcLeucine, and Fc for endogenous substrates as well as protein FSR. The heart under ECMO shows reduced oxidative metabolism of substrates, including amino acids, while maintaining 1) metabolic flexibility indicated by ability to respond to pyruvate and 2) a normal or increased capacity for global protein synthesis.

  7. Energizing eukaryotic cell-free protein synthesis with glucose metabolism.

    PubMed

    Anderson, Mark J; Stark, Jessica C; Hodgman, C Eric; Jewett, Michael C

    2015-07-01

    Eukaryotic cell-free protein synthesis (CFPS) is limited by the dependence on costly high-energy phosphate compounds and exogenous enzymes to power protein synthesis (e.g., creatine phosphate and creatine kinase, CrP/CrK). Here, we report the ability to use glucose as a secondary energy substrate to regenerate ATP in a Saccharomyces cerevisiae crude extract CFPS platform. We observed synthesis of 3.64±0.35 μg mL(-1) active luciferase in batch reactions with 16 mM glucose and 25 mM phosphate, resulting in a 16% increase in relative protein yield (μg protein/$ reagents) compared to the CrP/CrK system. Our demonstration provides the foundation for development of cost-effective eukaryotic CFPS platforms.

  8. Metabolic rate, latitude and thermal stability of roosts, but not phylogeny, affect rewarming rates of bats.

    PubMed

    Menzies, Allyson K; Webber, Quinn M R; Baloun, Dylan E; McGuire, Liam P; Muise, Kristina A; Coté, Damien; Tinkler, Samantha; Willis, Craig K R

    2016-10-01

    Torpor is an adaptation that allows many endotherms to save energy by abandoning the energetic cost of maintaining elevated body temperatures. Although torpor reduces energy consumption, the metabolic heat production required to arouse from torpor is energetically expensive and can impact the overall cost of torpor. The rate at which rewarming occurs can impact the cost of arousal, therefore, factors influencing rewarming rates of heterothermic endotherms could have influenced the evolution of rewarming rates and overall energetic costs of arousal from torpor. Bats are a useful taxon for studies of ecological and behavioral correlates of rewarming rate because of the widespread expression of heterothermy and ecological diversity across the >1200 known species. We used a comparative analysis of 45 bat species to test the hypothesis that ecological, behavioral, and physiological factors affect rewarming rates. We used basal metabolic rate (BMR) as an index of thermogenic capacity, and local climate (i.e., latitude of geographic range), roost stability and maximum colony size as ecological and behavioral predictors of rewarming rate. After controlling for phylogeny, high BMR was associated with rapid rewarming while species that live at higher absolute latitudes and in less thermally stable roosts also rewarmed most rapidly. These patterns suggests that some bat species rely on passive rewarming and social thermoregulation to reduce costs of rewarming, while others might rely on thermogenic capacity to maintain rapid rewarming rates in order to reduce energetic costs of arousal. Our results highlight species-specific traits associated with maintaining positive energy balance in a wide range of climates, while also providing insight into possible mechanisms underlying the evolution of heterothermy in endotherms.

  9. Metabolic rate, latitude and thermal stability of roosts, but not phylogeny, affect rewarming rates of bats.

    PubMed

    Menzies, Allyson K; Webber, Quinn M R; Baloun, Dylan E; McGuire, Liam P; Muise, Kristina A; Coté, Damien; Tinkler, Samantha; Willis, Craig K R

    2016-10-01

    Torpor is an adaptation that allows many endotherms to save energy by abandoning the energetic cost of maintaining elevated body temperatures. Although torpor reduces energy consumption, the metabolic heat production required to arouse from torpor is energetically expensive and can impact the overall cost of torpor. The rate at which rewarming occurs can impact the cost of arousal, therefore, factors influencing rewarming rates of heterothermic endotherms could have influenced the evolution of rewarming rates and overall energetic costs of arousal from torpor. Bats are a useful taxon for studies of ecological and behavioral correlates of rewarming rate because of the widespread expression of heterothermy and ecological diversity across the >1200 known species. We used a comparative analysis of 45 bat species to test the hypothesis that ecological, behavioral, and physiological factors affect rewarming rates. We used basal metabolic rate (BMR) as an index of thermogenic capacity, and local climate (i.e., latitude of geographic range), roost stability and maximum colony size as ecological and behavioral predictors of rewarming rate. After controlling for phylogeny, high BMR was associated with rapid rewarming while species that live at higher absolute latitudes and in less thermally stable roosts also rewarmed most rapidly. These patterns suggests that some bat species rely on passive rewarming and social thermoregulation to reduce costs of rewarming, while others might rely on thermogenic capacity to maintain rapid rewarming rates in order to reduce energetic costs of arousal. Our results highlight species-specific traits associated with maintaining positive energy balance in a wide range of climates, while also providing insight into possible mechanisms underlying the evolution of heterothermy in endotherms. PMID:27317837

  10. Multiple dietary supplements do not affect metabolic and cardio-vascular health.

    PubMed

    Soare, Andreea; Weiss, Edward P; Holloszy, John O; Fontana, Luigi

    2014-02-01

    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/m(2)) 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.

  11. Hepatocellular carcinoma protein carbonylation in virus C and metabolic syndrome patients.

    PubMed

    Martin, Fernando Ariel; Mebarki, Mouniya; Paradis, Valérie; Friguet, Bertrand; Radman, Miroslav

    2014-10-01

    Metabolic syndrome (MS) is becoming the leading cause of chronic liver diseases worldwide. Hepatocellular carcinoma (HCC) development in MS is peculiar compared to other chronic liver diseases. Carbohydrate and lipid metabolic imbalance in MS increase reactive oxygen species damaging proteins. In the present work we study the difference in protein oxidative damage (carbonylation) in human HCC derived from virus C infection (VHC) and from MS (MS_HCC) as the only subjacent cause. We selected a patient cohort containing of 10 non-tumoral and 10 tumoral liver resections in each study group (virus C and MS HCC) based on clinical patient history and histological parameters. Protein samples were labeled to saturation using CF 647-hydrazide™ dye. This approach allows us to perform carbonyl detection alongside with a DIGE experiment. We detected a total of 1184 spots with 36 differentially expressed proteins and 47 spots differentially carbonylated between VHC and MS_HCC (fold change >1.5, p<0.05). VHC up-regulated proteins are involved in signaling pathways related to cancer development such as signaling by EGFR, Wnt, Cdc20 and cell cycle. Further, up-regulated proteins in MS HCC, are implicated in metabolism of carbohydrates and amino acids. Differential carbonylation analysis between VHC and MS_HCC showed protein damage in proteins such as glucose phosphate isomerase, isocitrate dehydrogenase, and 3-ketoacyl-CoA thiolase. Higher protein carbonylation in MS_HCC samples was observed in proteins involved in redox response and lipid metabolism. In conclusion, the observed difference in protein oxidative damage between MS and Virus C derived carcinoma could account for the different cancer development pathway. PMID:26461368

  12. SVD identifies transcript length distribution functions from DNA microarray data and reveals evolutionary forces globally affecting GBM metabolism.

    PubMed

    Bertagnolli, Nicolas M; Drake, Justin A; Tennessen, Jason M; Alter, Orly

    2013-01-01

    To search for evolutionary forces that might act upon transcript length, we use the singular value decomposition (SVD) to identify the length distribution functions of sets and subsets of human and yeast transcripts from profiles of mRNA abundance levels across gel electrophoresis migration distances that were previously measured by DNA microarrays. We show that the SVD identifies the transcript length distribution functions as "asymmetric generalized coherent states" from the DNA microarray data and with no a-priori assumptions. Comparing subsets of human and yeast transcripts of the same gene ontology annotations, we find that in both disparate eukaryotes, transcripts involved in protein synthesis or mitochondrial metabolism are significantly shorter than typical, and in particular, significantly shorter than those involved in glucose metabolism. Comparing the subsets of human transcripts that are overexpressed in glioblastoma multiforme (GBM) or normal brain tissue samples from The Cancer Genome Atlas, we find that GBM maintains normal brain overexpression of significantly short transcripts, enriched in transcripts that are involved in protein synthesis or mitochondrial metabolism, but suppresses normal overexpression of significantly longer transcripts, enriched in transcripts that are involved in glucose metabolism and brain activity. These global relations among transcript length, cellular metabolism and tumor development suggest a previously unrecognized physical mode for tumor and normal cells to differentially regulate metabolism in a transcript length-dependent manner. The identified distribution functions support a previous hypothesis from mathematical modeling of evolutionary forces that act upon transcript length in the manner of the restoring force of the harmonic oscillator.

  13. The HIV Tat protein affects processing of ribosomal RNA precursor

    PubMed Central

    Ponti, Donatella; Troiano, Maria; Bellenchi, Gian Carlo; Battaglia, Piero A; Gigliani, Franca

    2008-01-01

    Background Inside the cell, the HIV Tat protein is mainly found in the nucleus and nucleolus. The nucleolus, the site of ribosome biogenesis, is a highly organized, non-membrane-bound sub-compartment where proteins with a high affinity for nucleolar components are found. While it is well known that Tat accumulates in the nucleolus via a specific nucleolar targeting sequence, its function in this compartment it still unknown. Results To clarify the significance of the Tat nucleolar localization, we induced the expression of the protein during oogenesis in Drosophila melanogaster strain transgenic for HIV-tat gene. Here we show that Tat localizes in the nucleoli of Drosophila oocyte nurse cells, where it specifically co-localizes with fibrillarin. Tat expression is accompanied by a significant decrease of cytoplasmic ribosomes, which is apparently related to an impairment of ribosomal rRNA precursor processing. Such an event is accounted for by the interaction of Tat with fibrillarin and U3 snoRNA, which are both required for pre-rRNA maturation. Conclusion Our data contribute to understanding the function of Tat in the nucleolus, where ribosomal RNA synthesis and cell cycle control take place. The impairment of nucleolar pre-rRNA maturation through the interaction of Tat with fibrillarin-U3snoRNA complex suggests a process by which the virus modulates host response, thus contributing to apoptosis and protein shut-off in HIV-uninfected cells. PMID:18559082

  14. Effect of Prolonged Simulated Microgravity on Metabolic Proteins in Rat Hippocampus: Steps toward Safe Space Travel.

    PubMed

    Wang, Yun; Javed, Iqbal; Liu, Yahui; Lu, Song; Peng, Guang; Zhang, Yongqian; Qing, Hong; Deng, Yulin

    2016-01-01

    Mitochondria are not only the main source of energy in cells but also produce reactive oxygen species (ROS), which result in oxidative stress when in space. This oxidative stress is responsible for energy imbalances and cellular damage. In this study, a rat tail suspension model was used in individual experiments for 7 and 21 days to explore the effect of simulated microgravity (SM) on metabolic proteins in the hippocampus, a vital brain region involved in learning, memory, and navigation. A comparative (18)O-labeled quantitative proteomic strategy was used to observe the differential expression of metabolic proteins. Forty-two and sixty-seven mitochondrial metabolic proteins were differentially expressed after 21 and 7 days of SM, respectively. Mitochondrial Complex I, III, and IV, isocitrate dehydrogenase and malate dehydrogenase were down-regulated. Moreover, DJ-1 and peroxiredoxin 6, which defend against oxidative damage, were up-regulated in the hippocampus. Western blot analysis of proteins DJ-1 and COX 5A confirmed the mass spectrometry results. Despite these changes in mitochondrial protein expression, no obvious cell apoptosis was observed after 21 days of SM. The results of this study indicate that the oxidative stress induced by SM has profound effects on metabolic proteins.

  15. Quantitative H2S-mediated protein sulfhydration reveals metabolic reprogramming during the integrated stress response.

    PubMed

    Gao, Xing-Huang; Krokowski, Dawid; Guan, Bo-Jhih; Bederman, Ilya; Majumder, Mithu; Parisien, Marc; Diatchenko, Luda; Kabil, Omer; Willard, Belinda; Banerjee, Ruma; Wang, Benlian; Bebek, Gurkan; Evans, Charles R; Fox, Paul L; Gerson, Stanton L; Hoppel, Charles L; Liu, Ming; Arvan, Peter; Hatzoglou, Maria

    2015-01-01

    The sulfhydration of cysteine residues in proteins is an important mechanism involved in diverse biological processes. We have developed a proteomics approach to quantitatively profile the changes of sulfhydrated cysteines in biological systems. Bioinformatics analysis revealed that sulfhydrated cysteines are part of a wide range of biological functions. In pancreatic β cells exposed to endoplasmic reticulum (ER) stress, elevated H2S promotes the sulfhydration of enzymes in energy metabolism and stimulates glycolytic flux. We propose that transcriptional and translational reprogramming by the integrated stress response (ISR) in pancreatic β cells is coupled to metabolic alternations triggered by sulfhydration of key enzymes in intermediary metabolism. PMID:26595448

  16. Predicting metabolic pathways of small molecules and enzymes based on interaction information of chemicals and proteins.

    PubMed

    Gao, Yu-Fei; Chen, Lei; Cai, Yu-Dong; Feng, Kai-Yan; Huang, Tao; Jiang, Yang

    2012-01-01

    Metabolic pathway analysis, one of the most important fields in biochemistry, is pivotal to understanding the maintenance and modulation of the functions of an organism. Good comprehension of metabolic pathways is critical to understanding the mechanisms of some fundamental biological processes. Given a small molecule or an enzyme, how may one identify the metabolic pathways in which it may participate? Answering such a question is a first important step in understanding a metabolic pathway system. By utilizing the information provided by chemical-chemical interactions, chemical-protein interactions, and protein-protein interactions, a novel method was proposed by which to allocate small molecules and enzymes to 11 major classes of metabolic pathways. A benchmark dataset consisting of 3,348 small molecules and 654 enzymes of yeast was constructed to test the method. It was observed that the first order prediction accuracy evaluated by the jackknife test was 79.56% in identifying the small molecules and enzymes in a benchmark dataset. Our method may become a useful vehicle in predicting the metabolic pathways of small molecules and enzymes, providing a basis for some further analysis of the pathway systems.

  17. Protein composition affects variation in coagulation properties of buffalo milk.

    PubMed

    Bonfatti, V; Gervaso, M; Rostellato, R; Coletta, A; Carnier, P

    2013-07-01

    The aim of this study was to investigate the effects exerted by the content of casein and whey protein fractions on variation of pH, rennet-coagulation time (RCT), curd-firming time (K20), and curd firmness of Mediterranean buffalo individual milk. Measures of milk protein composition and assessment of genotypes at CSN1S1 and CSN3 were obtained by reversed-phase HPLC analysis of 621 individual milk samples. Increased content of αS1-casein (CN) was associated with delayed coagulation onset and increased K20, whereas average pH, RCT, and K20 decreased when β-CN content increased. Milk with low κ-CN content exhibited low pH and RCT relative to milk with high content of κ-CN. Increased content of glycosylated κ-CN was associated with unfavorable effects on RCT. Effects of milk protein composition on curd firmness were less important than those on pH, RCT, and K20. Likely, this occurred as a consequence of the very short RCT of buffalo milk, which guaranteed a complete strengthening of the curd even in the restricted 31 min time of analysis of coagulation properties and for samples initially showing soft curds. Effects of CSN1S1-CSN3 genotypes on coagulation properties were not to be entirely ascribed to existing variation in milk protein composition associated with polymorphisms at CSN1S1 and CSN3 genes. Although the role of detailed milk protein composition in variation of cheese yield needs to be further investigated, findings of this study suggest that modification of the relative content of specific CN fractions can relevantly influence the behavior of buffalo milk during processing.

  18. Protein composition affects variation in coagulation properties of buffalo milk.

    PubMed

    Bonfatti, V; Gervaso, M; Rostellato, R; Coletta, A; Carnier, P

    2013-07-01

    The aim of this study was to investigate the effects exerted by the content of casein and whey protein fractions on variation of pH, rennet-coagulation time (RCT), curd-firming time (K20), and curd firmness of Mediterranean buffalo individual milk. Measures of milk protein composition and assessment of genotypes at CSN1S1 and CSN3 were obtained by reversed-phase HPLC analysis of 621 individual milk samples. Increased content of αS1-casein (CN) was associated with delayed coagulation onset and increased K20, whereas average pH, RCT, and K20 decreased when β-CN content increased. Milk with low κ-CN content exhibited low pH and RCT relative to milk with high content of κ-CN. Increased content of glycosylated κ-CN was associated with unfavorable effects on RCT. Effects of milk protein composition on curd firmness were less important than those on pH, RCT, and K20. Likely, this occurred as a consequence of the very short RCT of buffalo milk, which guaranteed a complete strengthening of the curd even in the restricted 31 min time of analysis of coagulation properties and for samples initially showing soft curds. Effects of CSN1S1-CSN3 genotypes on coagulation properties were not to be entirely ascribed to existing variation in milk protein composition associated with polymorphisms at CSN1S1 and CSN3 genes. Although the role of detailed milk protein composition in variation of cheese yield needs to be further investigated, findings of this study suggest that modification of the relative content of specific CN fractions can relevantly influence the behavior of buffalo milk during processing. PMID:23684020

  19. Mitochondrial Localization of Telomeric Protein TIN2 Links Telomere Regulation to Metabolic Control

    PubMed Central

    Chen, Liuh-Yow; Zhang, Yi; Zhang, Qinfen; Li, Hongzhi; Luo, Zhenhua; Fang, Hezhi; Kim, Sok Ho; Qin, Li; Yotnda, Patricia; Xu, Jianmin; Tu, Benjamin P.; Bai, Yidong; Songyang, Zhou

    2012-01-01

    Summary Both mitochondria, which are metabolic powerhouses, and telomeres, which help maintain genomic stability, have been implicated in cancer and aging. However, the signaling events that connect these two cellular structures remain poorly understood. Here we report that the canonical telomeric protein TIN2 is also a regulator of metabolism. TIN2 is recruited to telomeres and associates with multiple telomere regulators including TPP1. TPP1 interacts with TIN2 N-terminus, which contains overlapping mitochondrial and telomeric targeting sequences, and controls TIN2 localization. We have found that TIN2 is post-translationally processed in mitochondria, and regulates mitochondria oxidative phosphorylation. Reducing TIN2 expression by RNAi knockdown inhibited glycolysis and reactive oxygen species (ROS) and production, and enhanced ATP levels and oxygen consumption in cancer cells. These results suggest a link between telomeric proteins and metabolic control, providing an additional mechanism by which telomeric proteins regulate cancer and aging. PMID:22885005

  20. The TIM Barrel Architecture Facilitated the Early Evolution of Protein-Mediated Metabolism.

    PubMed

    Goldman, Aaron David; Beatty, Joshua T; Landweber, Laura F

    2016-01-01

    The triosephosphate isomerase (TIM) barrel protein fold is a structurally repetitive architecture that is present in approximately 10% of all enzymes. It is generally assumed that this ubiquity in modern proteomes reflects an essential historical role in early protein-mediated metabolism. Here, we provide quantitative and comparative analyses to support several hypotheses about the early importance of the TIM barrel architecture. An information theoretical analysis of protein structures supports the hypothesis that the TIM barrel architecture could arise more easily by duplication and recombination compared to other mixed α/β structures. We show that TIM barrel enzymes corresponding to the most taxonomically broad superfamilies also have the broadest range of functions, often aided by metal and nucleotide-derived cofactors that are thought to reflect an earlier stage of metabolic evolution. By comparison to other putatively ancient protein architectures, we find that the functional diversity of TIM barrel proteins cannot be explained simply by their antiquity. Instead, the breadth of TIM barrel functions can be explained, in part, by the incorporation of a broad range of cofactors, a trend that does not appear to be shared by proteins in general. These results support the hypothesis that the simple and functionally general TIM barrel architecture may have arisen early in the evolution of protein biosynthesis and provided an ideal scaffold to facilitate the metabolic transition from ribozymes, peptides, and geochemical catalysts to modern protein enzymes.

  1. Combined intervention of dietary soybean proteins and swim training: effects on bone metabolism in ovariectomized rats.

    PubMed

    Figard, Hélène; Mougin, Fabienne; Gaume, Vincent; Berthelot, Alain

    2006-01-01

    Soybean proteins, a rich source of isoflavones, taken immediately after an ovariectomy prevent bone loss in rats. Exercise-induced stimuli are essential for bone growth. Few studies exist about the combined effects of swim training and soybean protein supplementation on bone metabolism. So, the purpose of this study was to investigate, in 48 female Sprague-Dawley rats (12 weeks old) the effects of an 8-week swim-training regimen (1 h/day, 5 days/week) and dietary soybean proteins (200 g/kg diet) on bone metabolism. Rats were randomly assigned to four groups: (1) ovariectomized fed with a semisynthetic control diet; (2) ovariectomized fed with a soybean protein-enriched semisynthetic diet; (3) ovariectomized trained to exercise and fed with control diet; (4) ovariectomized trained to exercise and fed with a soybean protein diet. Following the treatment period, body weight gain was identical in the four groups. Soybean protein supplementation increased bone calcium content, and reduced plasma osteocalcin values, without significant modification of calcium balance and net calcium absorption. Swim training enhanced plasma and bone calcium content and calcium balance and net calcium absorption. It did not modify either plasma osteocalcin values or urinary deoxypyridinoline excretion. Both exercise and soybean protein intake increased plasma on bone calcium without modifying net calcium absorption or bone markers. In conclusion, we demonstrated, in ovariectomized rats, that swimming exercise and dietary supplementation with soy proteins do not have synergistic effects on calcium metabolism and bone markers.

  2. Engineering protein-based machines to emulate key steps of metabolism (biological energy conversion)

    PubMed

    Urry; Peng; Hayes; McPherson; Xu; Woods; Gowda; Pattanaik

    1998-04-01

    Metabolism is the conversion of available energy sources to those energy forms required for sustaining and propagating living organisms; this is simply biological energy conversion. Proteins are the machines of metabolism; they are the engines of motility and the other machines that interconvert energy forms not involving motion. Accordingly, metabolic engineering becomes the use of natural protein-based machines for the good of society. In addition, metabolic engineering can utilize the principles, whereby proteins function, to design new protein-based machines to fulfill roles for society that proteins have never been called upon throughout evolution to fulfill. This article presents arguments for a universal mechanism whereby proteins perform their diverse energy conversions; it begins with background information, and then asserts a set of five axioms for protein folding, assembly, and function and for protein engineering. The key process is the hydrophobic folding and assembly transition exhibited by properly balanced amphiphilic protein sequences. The fundamental molecular process is the competition for hydration between hydrophobic and polar, e.g., charged, residues. This competition determines Tt, the onset temperature for the hydrophobic folding and assembly transition, Nhh, the numbers of waters of hydrophobic hydration, and the pKa of ionizable functions. Reported acid-base titrations and pH dependence of microwave dielectric relaxation data simultaneously demonstrate the interdependence of Tt, Nhh and the pKa using a series of microbially prepared protein-based poly(30mers) with one glutamic acid residue per 30mer and with an increasing number of more hydrophobic phenylalanine residues replacing valine residues. Also, reduction of nicotinamides and flavins is shown to lower Tt, i.e., to increase hydrophobicity. Furthermore, the argument is presented, and related to an extended Henderson-Hasselbalch equation, wherein reduction of nicotinamides represents

  3. The Role of Maternal Dietary Proteins in Development of Metabolic Syndrome in Offspring

    PubMed Central

    Jahan-Mihan, Alireza; Rodriguez, Judith; Christie, Catherine; Sadeghi, Marjan; Zerbe, Tara

    2015-01-01

    The prevalence of metabolic syndrome and obesity has been increasing. Pre-natal environment has been suggested as a factor influencing the risk of metabolic syndrome in adulthood. Both observational and experimental studies showed that maternal diet is a major modifier of the development of regulatory systems in the offspring in utero and post-natally. Both protein content and source in maternal diet influence pre- and early post-natal development. High and low protein dams’ diets have detrimental effect on body weight, blood pressure191 and metabolic and intake regulatory systems in the offspring. Moreover, the role of the source of protein in a nutritionally adequate maternal diet in programming of food intake regulatory system, body weight, glucose metabolism and blood pressure in offspring is studied. However, underlying mechanisms are still elusive. The purpose of this review is to examine the current literature related to the role of proteins in maternal diets in development of characteristics of the metabolic syndrome in offspring. PMID:26561832

  4. Integrating gene and protein expression data with genome-scale metabolic networks to infer functional pathways

    PubMed Central

    2013-01-01

    Background The study of cellular metabolism in the context of high-throughput -omics data has allowed us to decipher novel mechanisms of importance in biotechnology and health. To continue with this progress, it is essential to efficiently integrate experimental data into metabolic modeling. Results We present here an in-silico framework to infer relevant metabolic pathways for a particular phenotype under study based on its gene/protein expression data. This framework is based on the Carbon Flux Path (CFP) approach, a mixed-integer linear program that expands classical path finding techniques by considering additional biophysical constraints. In particular, the objective function of the CFP approach is amended to account for gene/protein expression data and influence obtained paths. This approach is termed integrative Carbon Flux Path (iCFP). We show that gene/protein expression data also influences the stoichiometric balancing of CFPs, which provides a more accurate picture of active metabolic pathways. This is illustrated in both a theoretical and real scenario. Finally, we apply this approach to find novel pathways relevant in the regulation of acetate overflow metabolism in Escherichia coli. As a result, several targets which could be relevant for better understanding of the phenomenon leading to impaired acetate overflow are proposed. Conclusions A novel mathematical framework that determines functional pathways based on gene/protein expression data is presented and validated. We show that our approach is able to provide new insights into complex biological scenarios such as acetate overflow in Escherichia coli. PMID:24314206

  5. Acute metabolic acidosis decreases muscle protein synthesis but not albumin synthesis in humans.

    PubMed

    Kleger, G R; Turgay, M; Imoberdorf, R; McNurlan, M A; Garlick, P J; Ballmer, P E

    2001-12-01

    Chronic metabolic acidosis induces negative nitrogen balance by either increased protein breakdown or decreased protein synthesis. Few data exist regarding effects of acute metabolic acidosis on protein synthesis. We investigated fractional synthesis rates (FSRs) of muscle protein and albumin, plasma concentrations of insulin-like growth factor-I (IGF-I), thyroid-stimulating hormone (TSH), and thyroid hormones (free thyroxin [fT(4)] and triiodothyronine [fT(3)]) in seven healthy human volunteers after a stable controlled metabolic period of 5 days and again 48 hours later after inducing metabolic acidosis by oral ammonium chloride intake (4.2 mmol/kg/d divided in six daily doses). Muscle and albumin FSRs were obtained by the [(2)H(5)ring]phenylalanine flooding technique. Ammonium chloride induced a significant decrease in pH (7.43 +/- 0.02 versus 7.32 +/- 0.04; P < 0.0001) and bicarbonate concentration (24.6 +/- 1.6 versus 16.0 +/- 2.7 mmol/L; P < 0.0001) within 48 hours. Nitrogen balance decreased significantly on the second day of acidosis. The FSR of muscle protein decreased (1.94 +/- 0.25 versus 1.30 +/- 0.39; P < 0.02), whereas the FSR of albumin remained constant. TSH levels increased significantly (1.1 +/- 0.5 versus 1.9 +/- 1.1 mU/L; P = 0.03), whereas IGF-I, fT(4), and fT(3) levels showed no significant change. We conclude that acute metabolic acidosis for 48 hours in humans induces a decrease in muscle protein synthesis, which contributes substantially to a negative nitrogen balance. In contrast to prolonged metabolic acidosis of 7 days, a short period of acidosis in the present study did not downregulate albumin synthesis.

  6. Spaceflight and protein metabolism, with special reference to humans

    NASA Technical Reports Server (NTRS)

    Stein, T. P.; Gaprindashvili, T.

    1994-01-01

    Human space missions have shown that human spaceflight is associated with a loss of body protein. Specific changes include a loss of lean body mass, decreased muscle mass in the calves, decreased muscle strength, and changes in plasma proteins and amino acids. The major muscle loss is believed to be associated with the antigravity (postural) muscle. The most significant loss of protein appears to occur during the first month of flight. The etiology is believed to be multifactorial with contributions from disuse atrophy, undernutrition, and a stress type of response. This article reviews the results of American and Russian space missions to investigate this problem in humans, monkeys, and rats. The relationship of the flight results with ground-based models including bedrest for humans and hindlimb unweighting for rats is also discussed. The results suggest that humans adapt to spaceflight much better than either monkeys or rats.

  7. Diet-Induced Alterations of Host Cholesterol Metabolism Are Likely To Affect the Gut Microbiota Composition in Hamsters

    PubMed Central

    Martínez, Inés; Perdicaro, Diahann J.; Brown, Andrew W.; Hammons, Susan; Carden, Trevor J.; Carr, Timothy P.; Eskridge, Kent M.

    2013-01-01

    The gastrointestinal microbiota affects the metabolism of the mammalian host and has consequences for health. However, the complexity of gut microbial communities and host metabolic pathways make functional connections difficult to unravel, especially in terms of causation. In this study, we have characterized the fecal microbiota of hamsters whose cholesterol metabolism was extensively modulated by the dietary addition of plant sterol esters (PSE). PSE intake induced dramatic shifts in the fecal microbiota, reducing several bacterial taxa within the families Coriobacteriaceae and Erysipelotrichaceae. The abundance of these taxa displayed remarkably high correlations with host cholesterol metabolites. Most importantly, the associations between several bacterial taxa with fecal and biliary cholesterol excretion showed an almost perfect fit to a sigmoidal nonlinear model of bacterial inhibition, suggesting that host cholesterol excretion can shape microbiota structure through the antibacterial action of cholesterol. In vitro experiments suggested a modest antibacterial effect of cholesterol, and especially of cholesteryl-linoleate, but not plant sterols when included in model bile micelles. The findings obtained in this study are relevant to our understanding of gut microbiota-host lipid metabolism interactions, as they provide the first evidence for a role of cholesterol excreted with the bile as a relevant host factor that modulates the gut microbiota. The findings further suggest that the connections between Coriobacteriaceae and Erysipelotrichaceae and host lipid metabolism, which have been observed in several studies, could be caused by a metabolic phenotype of the host (cholesterol excretion) affecting the gut microbiota. PMID:23124234

  8. Role of acyl carrier protein isoforms in plant lipid metabolism

    SciTech Connect

    Not Available

    1990-01-01

    Although acyl carrier protein (ACP) is the best studied protein in plant fatty acid biosynthesis, the in vivo forms of ACPs and their steady state pools have not been examined previously in either seed or leaf. Information about the relative pool sizes of free ACP and its acyl-ACP intermediates is essential for understanding regulation of de novo fatty acid biosynthesis in plants. In this study we utilized antibodies directed against spinach ACP as a sensitive assay to analyze the acyl groups while they were still covalently attached to ACPs. 4 refs., 4 figs.

  9. Dietary protein during gestation affects placental development in heifers.

    PubMed

    Sullivan, T M; Micke, G C; Magalhaes, R S; Phillips, N J; Perry, V E A

    2009-09-01

    The influence of nutritional protein during the first and second trimesters of pregnancy on placental measures at term and caruncle numbers in the uteri of adult offspring was determined in composite beef heifers. At artificial insemination (AI), heifers were divided by weight and composite genotype into four dietary treatment groups, identified by the level of protein components fed during the first and second trimesters: high/high (HH), high/low (HL), low/high (LH), low/low (LL). Expelled placentas were collected and weighed, and cotyledons were dissected, counted, weighed, and measured. Uteri from mature female offspring were dissected at slaughter and caruncles counted. The number of cotyledons in the expelled placenta was increased by high dietary protein in the second trimester (P=0.02) and varied with genotype (P=0.03). Placental weight was influenced by maternal undernutrition during early gestation dependent on dam genotype (P=0.001). Placental efficiency, as determined by calf weight:placental weight, increased with dam age (P=0.03). Calf birth weight was closely associated with placental weight (P=0.002) and cotyledonary weight (P=0.001) and surface area (P=0.04), but not with the number of cotyledons. Leptin concentrations during early (R=-0.29) and late gestation (R=-0.25) correlated with placental weight, and Insulin-like growth factor binding proteins throughout gestation correlated with the number of cotyledons (R=-0.28 to-0.33). The number of uterine caruncles in the nonpregnant adult offspring did not correlate with the dam's genotype, nutrition treatment, or cotyledon number in the expelled placenta.

  10. Protein sources for finishing calves as affected by management system.

    PubMed

    Sindt, M H; Stock, R A; Klopfenstein, T J; Vieselmeyer, B A

    1993-03-01

    Two beef production systems were evaluated in conjunction with an evaluation of escape protein sources for finishing calves. Two hundred forty crossbred steers and 80 crossbred heifer calves (BW = 267 +/- 2 kg) were split into two groups: 1) control, finished (207 d) after a 3-wk feedlot adjustment period and 2) grazing cornstalks for 74 d after a 3-wk feedlot adjustment period, then finished (164 d). Finishing treatments were sources and proportions of supplemental CP: 1) urea 100%; 2) soybean meal (SBM) 100%; 3) blood meal (BM) 50%, urea 50%; 4) feather meal (FTH) 50%, urea 50%; 5) SBM 50%, FTH 25%, urea 25%; 6) SBM 25%, FTH 38%, urea 37%; 7) FTH 25%, BM 25%, urea 50%, and 8) FTH 38%, BM 13%, urea 50%. Treatments 1 to 8 were fed in dry-rolled corn (DRC)-based diets. Treatments 9 and 10 were supplement Treatments 1 and 7 fed in diets based on high-moisture corn. Calves finished after a 74-d period of grazing cornstalks consumed more feed (P < .01) and gained faster (P < .01) but were less efficient (P < .05) than calves finished directly after weaning. Although not statistically different, calves finished after grazing cornstalks and supplemented with natural protein in the feedlot were 7% more efficient than calves supplemented with urea alone. Efficiency of calves finished directly after weaning was similar for calves supplemented with natural protein or urea alone. Supplementing SBM/FTH/urea or BM/FTH/urea improved feed efficiency compared with supplementing FTH/urea alone. These data suggest that allowing calves to graze cornstalks before finishing is a possible management option, but this system may require more metabolizable protein in the finishing diet to maximize feed efficiency if the calves are expressing compensatory growth. PMID:8463161

  11. 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.

  12. Pathway analysis of Pichia pastoris to elucidate methanol metabolism and its regulation for production of recombinant proteins.

    PubMed

    Unrean, Pornkamol

    2014-01-01

    This research rationally analyzes metabolic pathways of Pichia pastoris to study the metabolic flux responses of this yeast under methanol metabolism. A metabolic model of P. pastoris was constructed and analyzed by elementary mode analysis (EMA). EMA was used to comprehensively identify the cell's metabolic flux profiles and its underlying regulation mechanisms for the production of recombinant proteins from methanol. Change in phenotypes and flux profiles during methanol adaptation with varying feed mixture of glycerol and methanol was examined. EMA identified increasing and decreasing fluxes during the glycerol-methanol metabolic shift, which well agreed with experimental observations supporting the validity of the metabolic network model. Analysis of all the identified pathways also led to the determination of the metabolic capacities as well as the optimum metabolic pathways for recombinant protein synthesis during methanol induction. The network sensitivity analysis revealed that the production of proteins can be improved by manipulating the flux ratios at the pyruvate branch point. In addition, EMA suggested that protein synthesis is optimum under hypoxic culture conditions. The metabolic modeling and analysis presented in this study could potentially form a valuable knowledge base for future research on rational design and optimization of P. pastoris by determining target genes, pathways, and culture conditions for enhanced recombinant protein synthesis. The metabolic pathway analysis is also of considerable value for production of therapeutic proteins by P. pastoris in biopharmaceutical applications.

  13. Fluoranthene metabolism and associated proteins in Mycobacterium sp. JS14.

    PubMed

    Lee, Sung-Eun; Seo, Jong-Su; Keum, Young-Soo; Lee, Kwang-Jun; Li, Qing X

    2007-06-01

    Fluoranthene is a polycyclic aromatic hydrocarbon (PAH) commonly present in PAH-contaminated soils. We studied fluoranthene catabolism and associated proteins in Mycobacterium sp. JS14, a bacterium isolated from a PAH-contaminated soil in Hilo (HI, USA). Fluoranthene degrades in at least three separated pathways via 1-indanone, 2',3'-dihydroxybiphenyl-2,3,-dicarboxylic acid, and naphthalene-1,8-dicarboxylic acid. Part of the diverse catabolism is converged into phthalate catabolism. An increased expression of 25 proteins related to fluoranthene catabolism is found with 1-D PAGE or 2-DE and nano-LC-MS/MS. Detection of fluoranthene catabolism associated proteins coincides well with its multiple degradation pathways that are mapped via metabolites identified. Among the up-regulated proteins, PAH ring-hydroxylating dioxygenase alpha-subunit and beta-subunit and 2,3-dihydroxybiphenyl 1,2-dioxygenase are notably induced. The up-regulation of trans-2-carboxybenzalpyruvate hydratase suggests that some of fluoranthene metabolites may be further degraded through aromatic dicarboxylic acid pathways. Catalase and superoxide dismutase were up-regulated to control unexpected oxidative stress during the fluoranthene catabolism. The up-regulation of chorismate synthase and nicotine-nucleotide phosphorylase may be necessary for sustaining shikimate pathway and pyrimidine biosynthesis, respectively. A fluoranthene degradation pathway for Mycobacterium sp. JS14 was proposed and confirmed by proteomic study by identifying almost all the enzymes required during the initial steps of fluoranthene degradation. PMID:17514677

  14. Effects of atorvastatin on human c reactive protein metabolism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Statins are known to reduce plasma C-reactive protein (CRP) concentrations. Our goals were to define the mechanisms by which CRP was reduced by maximal dose atorvastatin. Eight subjects with combined hyperlipidemia (5 men and 3 postmenopausal women) were enrolled in a randomized, placebo-controlled...

  15. Alkyl-methylimidazolium ionic liquids affect the growth and fermentative metabolism of Clostridium sp

    SciTech Connect

    Nancharaiah, Y.V.; Francis, A.

    2011-06-01

    In this study, the effect of ionic liquids, 1-ethyl-3-methylimidazolium acetate [EMIM][Ac], 1-ethyl-3-methylimidazolium diethylphosphate [EMIM][DEP], and 1-methyl-3-methylimidazolium dimethylphosphate [MMIM][DMP] on the growth and glucose fermentation of Clostridium sp. was investigated. Among the three ionic liquids tested, [MMIM][DMP] was found to be least toxic. Growth of Clostridium sp. was not inhibited up to 2.5, 4 and 4 g L{sup -1} of [EMIM][Ac], [EMIM][DEP] and [MMIM][DMP], respectively. [EMIM][Ac] at <2.5 g L{sup -1}, showed hormetic effect and stimulated the growth and fermentation by modulating medium pH. Total organic acid production increased in the presence of 2.5 and 2 g L{sup -1} of [EMIM][Ac] and [MMIM][DMP]. Ionic liquids had no significant influence on alcohol production at <2.5 g L{sup -1}. Total gas production was affected by ILs at {ge}2.5 g L{sup -1} and varied with type of methylimidazolium IL. Overall, the results show that the growth and fermentative metabolism of Clostridium sp. is not impacted by ILs at concentrations below 2.5 g L{sup -1}.

  16. Dietary fatty acids early in life affect lipid metabolism and adiposity in young rats.

    PubMed

    Silva, Ana Paula S; Guimarães, Daniella E D; Mizurini, Daniella M; Maia, Ingrid C; Ortiz-Costa, Susana; Sardinha, Fátima L; do Carmo, Maria G Tavares

    2006-06-01

    The purpose of this study was to evaluate the effects of four isoenergetic diets of differing fat composition on blood lipid profile and adiposity in young rats. Diets containing different lipid sources--partially hydrogenated vegetable oil (PHVO), palm oil (PO), canola oil (CO), and soy oil (SO)--were fed to lactating rats during the 21 days of lactation, and then fed to young males following weaning until the 45th day of life. In vivo lipogenesis rate (LR), lipid content (LC), relative level of FA, and the activity of lipoprotein lipase (LPL) enzyme were measured in epididymal adipose tissue (EPI). Fasting blood lipoproteins and LC in the carcass were also appraised. Body weight of PO and PHVO groups was significantly higher than CO and SO groups from day 14 of lactation to day 45, despite the lower food intake in the PHVO group. PO and PHVO groups presented higher LR and LC in EPI than SO and CO groups. Carcass fat content was significantly higher in PHVO and PO groups than in CO and SO groups. The LPL activity in EPI was unaffected by dietary lipids. PHVO group had increased total cholesterol and TAG concentrations in comparison with the PO group, and significantly lower HDL level compared with the other groups. These results show that the kind of FA in the dietary lipid offered early in life can affect lipid metabolism and adiposity.

  17. Zinc deficiency (ZD) without starvation affects thyroid hormone metabolism of rats

    SciTech Connect

    Lukaski, H.C.; Smith, S.M.; Hall, C.B.; Bucher, D.R. )

    1991-03-15

    Young rats fed diets severely deficient in Zn exhibit impaired growth and endocrine function. These hormone effects may be confounded by cyclical feeding and starvation. To examine the effects of zinc deficiency (ZD) with and without starvation, 40 male weanling Sprague-Dawley rats were fed a semipurified diet containing all essential nutrients and 30 ppm Zn until they weighed 150 g, then were matched by weight into four groups and were fed one of the following diets for 28d: ad lib control Zn diet, marginal ZD diet, severe ZD diet, and C diet pair-fed (PF) in amounts consumed by matched ZD1 rat. Food intake was depressed in ZD1; body weights were reduced in ZD1 and PF. There was no difference in either food intake or weight gain between C and ZD6. ZD reduced liver and femur Zn concentrations. Plasma thyroxine (T{sub 4}) concentration was greater in ZD6 then ZD1 or PF, but less than C; triodothyronine concentration was less in PF than C, but similar to ZD1 and ZD6. Hepatic T{sub 4}-5{prime}-deiodinase activity was greater in ZD6 than ZD1 or PF, but less than C. These findings indicate that altered thyroid hormone metabolism of severe ZD is related to Zn intake and starvation, whereas ZD uncomplicated by starvation affects peripheral deiodination of T{sub 4}, and suggests altered rates of thyroid hormone synthesis or degradation.

  18. Developmental changes in carbon and nitrogen metabolism affect tea quality in different leaf position.

    PubMed

    Li, Zhi-Xin; Yang, Wei-Jun; Ahammed, Golam Jalal; Shen, Chen; Yan, Peng; Li, Xin; Han, Wen-Yan

    2016-09-01

    Leaf position represents a specific developmental stage that influences both photosynthesis and respiration. However, the precise relationships between photosynthesis and respiration in different leaf position that affect tea quality are largely unknown. Here, we show that the effective quantum yield of photosystem II [ΦPSⅡ] as well as total chlorophyll concentration (TChl) of tea leaves increased gradually with leaf maturity. Moreover, respiration rate (RR) together with total nitrogen concentration (TN) decreased persistently, but total carbon remained unchanged during leaf maturation. Analyses of major N-based organic compounds revealed that decrease in TN was attributed to a significant decrease in the concentration of caffeine and amino acids (AA) in mature leaves. Furthermore, soluble sugar (SS) decreased, but starch concentration increased with leaf maturity, indicating that source-sink relationship was altered during tea leaf development. Detailed correlation analysis showed that ΦPSⅡ was negatively correlated with RR, SS, starch, tea polyphenol (TP), total catechins and TN, but positively correlated with TChl; while RR was positively correlated with TN, SS, TP and caffeine, but negatively correlated with TChl and starch concentrations. Our results suggest that biosynthesis of chlorophyll, catechins and polyphenols is closely associated with photosynthesis and respiration in different leaf position that greatly influences the relationship between primary and secondary metabolism in tea plants. PMID:27380366

  19. Inhibitors of plant invertases do not affect the structurally related enzymes of fructan metabolism.

    PubMed

    Kusch, Ute; Harms, Karsten; Rausch, Thomas; Greiner, Steffen

    2009-01-01

    Plant fructan active enzymes (FAZYs), including the enzymes involved in inulin metabolism, namely sucrose:sucrose 1-fructosyltransferase (1-SST; EC 2.4.1.99), fructan:fructan 1-fructosyltransferase (1-FFT; EC 2.4.1.100) and fructan 1-exohydrolase (1-FEH; EC 3.2.1.153), are evolutionarily related to acid invertases (AIs), that is, plant cell wall invertase (CWI) and vacuolar invertase (VI). Acid invertases are post-translationally controlled by proteinaceous inhibitors. Whether FAZYs are subject to similar controls is not known. To probe their possible interactions with invertase inhibitors, we transiently expressed chicory (Cichorium intybus) FAZYs, as well as several previously characterized invertase inhibitors from nonfructan species, and the C. intybus cell wall/vacuolar inhibitor of fructosidase (CiC/VIF), a putative invertase inhibitor of a fructan-accumulating plant, in leaves of Nicotiana benthamiana. Leaf extracts containing recombinant, enzymatically active FAZYs were used to explore the interaction with invertase inhibitors. Neither heterologous inhibitors nor CiC/VIF affected FAZY activities. CiC/VIF was confirmed as an AI inhibitor with a stronger effect on CWI than on VI. Its expression in planta was developmentally regulated (high in taproots, and undetectable in leaves and flowers). In agreement with its target specificities, CiC/VIF was associated with the cell wall. It is concluded that subtle structural differences between AIs and FAZYs result in pronounced selectivity of inhibitor action.

  20. Developmental changes in carbon and nitrogen metabolism affect tea quality in different leaf position.

    PubMed

    Li, Zhi-Xin; Yang, Wei-Jun; Ahammed, Golam Jalal; Shen, Chen; Yan, Peng; Li, Xin; Han, Wen-Yan

    2016-09-01

    Leaf position represents a specific developmental stage that influences both photosynthesis and respiration. However, the precise relationships between photosynthesis and respiration in different leaf position that affect tea quality are largely unknown. Here, we show that the effective quantum yield of photosystem II [ΦPSⅡ] as well as total chlorophyll concentration (TChl) of tea leaves increased gradually with leaf maturity. Moreover, respiration rate (RR) together with total nitrogen concentration (TN) decreased persistently, but total carbon remained unchanged during leaf maturation. Analyses of major N-based organic compounds revealed that decrease in TN was attributed to a significant decrease in the concentration of caffeine and amino acids (AA) in mature leaves. Furthermore, soluble sugar (SS) decreased, but starch concentration increased with leaf maturity, indicating that source-sink relationship was altered during tea leaf development. Detailed correlation analysis showed that ΦPSⅡ was negatively correlated with RR, SS, starch, tea polyphenol (TP), total catechins and TN, but positively correlated with TChl; while RR was positively correlated with TN, SS, TP and caffeine, but negatively correlated with TChl and starch concentrations. Our results suggest that biosynthesis of chlorophyll, catechins and polyphenols is closely associated with photosynthesis and respiration in different leaf position that greatly influences the relationship between primary and secondary metabolism in tea plants.

  1. Glucocorticoids and 11β-HSD1 are major regulators of intramyocellular protein metabolism

    PubMed Central

    Hassan-Smith, Zaki K; Doig, Craig L; Sherlock, Mark; Stewart, Paul M; Lavery, Gareth G

    2016-01-01

    The adverse metabolic effects of prescribed and endogenous glucocorticoid excess, ‘Cushing’s syndrome’, create a significant health burden. While skeletal muscle atrophy and resultant myopathy is a clinical feature, the molecular mechanisms underpinning these changes are not fully defined. We have characterized the impact of glucocorticoids upon key metabolic pathways and processes regulating muscle size and mass including: protein synthesis, protein degradation, and myoblast proliferation in both murine C2C12 and human primary myotube cultures. Furthermore, we have investigated the role of pre-receptor modulation of glucocorticoid availability by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) in these processes. Corticosterone (CORT) decreased myotube area, decreased protein synthesis, and increased protein degradation in murine myotubes. This was supported by decreased mRNA expression of insulin-like growth factor (IGF1), decreased activating phosphorylation of mammalian target of rapamycin (mTOR), decreased phosphorylation of 4E binding protein 1 (4E-BP1), and increased mRNA expression of key atrophy markers including: atrogin-1, forkhead box O3a (FOXO3a), myostatin (MSTN), and muscle-ring finger protein-1 (MuRF1). These findings were endorsed in human primary myotubes, where cortisol also decreased protein synthesis and increased protein degradation. The effects of 11-dehydrocorticosterone (11DHC) (in murine myotubes) and cortisone (in human myotubes) on protein metabolism were indistinguishable from that of CORT/cortisol treatments. Selective 11β-HSD1 inhibition blocked the decrease in protein synthesis, increase in protein degradation, and reduction in myotube area induced by 11DHC/cortisone. Furthermore, CORT/cortisol, but not 11DHC/cortisone, decreased murine and human myoblast proliferative capacity. Glucocorticoids are potent regulators of skeletal muscle protein homeostasis and myoblast proliferation. Our data underscores the potential use

  2. 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.

  3. 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. PMID:26951140

  4. Myocardial Oxidative Metabolism and Protein Synthesis during Mechanical Circulatory Support by Extracorporeal Membrane Oxygenation

    SciTech Connect

    Priddy, MD, Colleen M.; Kajimoto, Masaki; Ledee, Dolena; Bouchard, Bertrand; Isern, Nancy G.; Olson, Aaron; Des Rosiers, Christine; Portman, Michael A.

    2013-02-01

    Extracorporeal membrane oxygenation (ECMO) provides mechanical circulatory support essential for survival in infants and children with acute cardiac decompensation. However, ECMO also causes metabolic disturbances, which contribute to total body wasting and protein loss. Cardiac stunning can also occur which prevents ECMO weaning, and contributes to high mortality. The heart may specifically undergo metabolic impairments, which influence functional recovery. We tested the hypothesis that ECMO alters oxidative. We focused on the amino acid leucine, and integration with myocardial protein synthesis. We used a translational immature swine model in which we assessed in heart (i) the fractional contribution of leucine (FcLeucine) and pyruvate (FCpyruvate) to mitochondrial acetyl-CoA formation by nuclear magnetic resonance and (ii) global protein fractional synthesis (FSR) by gas chromatography-mass spectrometry. Immature mixed breed Yorkshire male piglets (n = 22) were divided into four groups based on loading status (8 hours of normal circulation or ECMO) and intracoronary infusion [13C6,15N]-L-leucine (3.7 mM) alone or with [2-13C]-pyruvate (7.4 mM). ECMO decreased pulse pressure and correspondingly lowered myocardial oxygen consumption (~ 40%, n = 5), indicating decreased overall mitochondrial oxidative metabolism. However, FcLeucine was maintained and myocardial protein FSR was marginally increased. Pyruvate addition decreased tissue leucine enrichment, FcLeucine, and Fc for endogenous substrates as well as protein FSR. Conclusion: The heart under ECMO shows reduced oxidative metabolism of substrates, including amino acids, while maintaining (i) metabolic flexibility indicated by ability to respond to pyruvate, and (ii) a normal or increased capacity for global protein synthesis, suggesting an improved protein balance.

  5. Maternal protein restriction impairs the transcriptional metabolic flexibility of skeletal muscle in adult rat offspring.

    PubMed

    da Silva Aragão, Raquel; Guzmán-Quevedo, Omar; Pérez-García, Georgina; Manhães-de-Castro, Raul; Bolaños-Jiménez, Francisco

    2014-08-14

    Skeletal muscle exhibits a remarkable flexibility in the usage of fuel in response to the nutrient intake and energy demands of the organism. In fact, increased physical activity and fasting trigger a transcriptional programme in skeletal muscle cells leading to a switch from carbohydrate to lipid oxidation. Impaired metabolic flexibility has been reported to be associated with obesity and type 2 diabetes, but it is not known whether the disability to adapt to metabolic demands is a cause or a consequence of these pathological conditions. Inasmuch as a poor nutritional environment during early life is a predisposing factor for the development of metabolic diseases in adulthood, in the present study, we aimed to determine the long-term effects of maternal malnutrition on the metabolic flexibility of offspring skeletal muscle. To this end, the transcriptional responses of the soleus and extensor digitorum longus muscles to fasting were evaluated in adult rats born to dams fed a control (17 % protein) or a low-protein (8 % protein, protein restricted (PR)) diet throughout pregnancy and lactation. With the exception of reduced body weight and reduced plasma concentrations of TAG, PR rats exhibited a metabolic profile that was the same as that of the control rats. In the fed state, PR rats exhibited an enhanced expression of key regulatory genes of fatty acid oxidation including CPT1a, PGC-1α, UCP3 and PPARα and an impaired expression of genes that increase the capacity for fat oxidation in response to fasting. These results suggest that impaired metabolic inflexibility precedes and may contribute to the development of metabolic disorders associated with early malnutrition. PMID:24823946

  6. In Silico Studies of C3 Metabolic Pathway Proteins of Wheat (Triticum aestivum)

    PubMed Central

    Naeem, Muhammad Kashif; Rauf, Sobiah; Iqbal, Hina; Nawaz Shah, Muhammad Kausar; Mir, Asif

    2013-01-01

    Photosynthesis is essential for plant productivity and critical for plant growth. More than 90% of plants have a C3 metabolic pathway primarily for carbon assimilation. Improving crop yields for food and fuel is a major challenge for plant biology. To enhance the production of wheat there is need to adopt the strategies that can create the change in plants at the molecular level. During the study we have employed computational bioinformatics and interactomics analysis of C3 metabolic pathway proteins in wheat. The three-dimensional protein modeling provided insight into molecular mechanism and enhanced understanding of physiological processes and biological systems. Therefore in our study, initially we constructed models for nine proteins involving C3 metabolic pathway, as these are not determined through wet lab experiment (NMR, X-ray Crystallography) and not available in RCSB Protein Data Bank and UniProt KB. On the basis of docking interaction analysis, we proposed the schematic diagram of C3 metabolic pathway. Accordingly, there also exist vice versa interactions between 3PGK and Rbcl. Future site and directed mutagenesis experiments in C3 plants could be designed on the basis of our findings to confirm the predicted protein interactions. PMID:23484105

  7. Global Profiling of Protein Lysine Malonylation in Escherichia coli Reveals Its Role in Energy Metabolism.

    PubMed

    Qian, Lili; Nie, Litong; Chen, Ming; Liu, Ping; Zhu, Jun; Zhai, Linhui; Tao, Sheng-Ce; Cheng, Zhongyi; Zhao, Yingming; Tan, Minjia

    2016-06-01

    Protein lysine malonylation is a recently identified post-translational modification (PTM), which is evolutionarily conserved from bacteria to mammals. Although analysis of lysine malonylome in mammalians suggested that this modification was related to energy metabolism, the substrates and biological roles of malonylation in prokaryotes are still poorly understood. In this study, we performed qualitative and quantitative analyses to globally identify lysine malonylation substrates in Escherichia coli. We identified 1745 malonylation sites in 594 proteins in E. coli, representing the first and largest malonylome data set in prokaryotes up to date. Bioinformatic analyses showed that lysine malonylation was significantly enriched in protein translation, energy metabolism pathways and fatty acid biosynthesis, implying the potential roles of protein malonylation in bacterial physiology. Quantitative proteomics by fatty acid synthase inhibition in both auxotrophic and prototrophic E. coli strains revealed that lysine malonylation is closely associated with E. coli fatty acid metabolism. Protein structural analysis and mutagenesis experiment suggested malonylation could impact enzymatic activity of citrate synthase, a key enzyme in citric acid (TCA) cycle. Further comparative analysis among lysine malonylome, succinylome and acetylome data showed that these three modifications could participate in some similar enriched metabolism pathways, but they could also possibly play distinct roles such as in fatty acid synthesis. These data expanded our knowledge of lysine malonylation in prokaryotes, providing a resource for functional study of lysine malonylation in bacteria. PMID:27183143

  8. The RHOX Homeodomain Proteins Regulate the Expression of Insulin and Other Metabolic Regulators in the Testis*

    PubMed Central

    MacLean, James A.; Hu, Zhiying; Welborn, Joshua P.; Song, Hye-Won; Rao, Manjeet K.; Wayne, Chad M.; Wilkinson, Miles F.

    2013-01-01

    Defects in cellular metabolism have been widely implicated in causing male infertility, but there has been little progress in understanding the underlying mechanism. Here we report that several key metabolism genes are regulated in the testis by Rhox5, the founding member of a large X-linked homeobox gene cluster. Among these Rhox5-regulated genes are insulin 2 (Ins2), resistin (Retn), and adiponectin (Adipoq), all of which encode secreted proteins that have profound and wide-ranging effects on cellular metabolism. The ability of Rhox5 to regulate their levels in the testis has the potential to dictate metabolism locally in this organ, given the existence of the blood-testes barrier. We demonstrate that Ins2 is a direct target of Rhox5 in Sertoli cells, and we show that this regulation is physiologically significant, because Rhox5-null mice fail to up-regulate Ins2 expression during the first wave of spermatogenesis and have insulin-signaling defects. We identify other Rhox family members that induce Ins2 transcription, define protein domains and homeodomain amino acid residues crucial for this property, and demonstrate that this regulation is conserved. Rhox5-null mice also exhibit altered expression of other metabolism genes, including those encoding the master transcriptional regulators of metabolism, PPARG and PPARGC1A, as well as SCD1, the rate-limiting enzyme for fatty acid metabolism. These results, coupled with the known roles of RHOX5 and its target metabolism genes in spermatogenesis in vivo, lead us to propose a model in which RHOX5 is a central transcription factor that promotes the survival of male germ cells via its effects on cellular metabolism. PMID:24121513

  9. The RHOX homeodomain proteins regulate the expression of insulin and other metabolic regulators in the testis.

    PubMed

    MacLean, James A; Hu, Zhiying; Welborn, Joshua P; Song, Hye-Won; Rao, Manjeet K; Wayne, Chad M; Wilkinson, Miles F

    2013-11-29

    Defects in cellular metabolism have been widely implicated in causing male infertility, but there has been little progress in understanding the underlying mechanism. Here we report that several key metabolism genes are regulated in the testis by Rhox5, the founding member of a large X-linked homeobox gene cluster. Among these Rhox5-regulated genes are insulin 2 (Ins2), resistin (Retn), and adiponectin (Adipoq), all of which encode secreted proteins that have profound and wide-ranging effects on cellular metabolism. The ability of Rhox5 to regulate their levels in the testis has the potential to dictate metabolism locally in this organ, given the existence of the blood-testes barrier. We demonstrate that Ins2 is a direct target of Rhox5 in Sertoli cells, and we show that this regulation is physiologically significant, because Rhox5-null mice fail to up-regulate Ins2 expression during the first wave of spermatogenesis and have insulin-signaling defects. We identify other Rhox family members that induce Ins2 transcription, define protein domains and homeodomain amino acid residues crucial for this property, and demonstrate that this regulation is conserved. Rhox5-null mice also exhibit altered expression of other metabolism genes, including those encoding the master transcriptional regulators of metabolism, PPARG and PPARGC1A, as well as SCD1, the rate-limiting enzyme for fatty acid metabolism. These results, coupled with the known roles of RHOX5 and its target metabolism genes in spermatogenesis in vivo, lead us to propose a model in which RHOX5 is a central transcription factor that promotes the survival of male germ cells via its effects on cellular metabolism.

  10. Increasing levels of dietary crystalline methionine affect plasma methionine profiles, ammonia excretion, and the expression of genes related to the hepatic intermediary metabolism in rainbow trout (Oncorhynchus mykiss).

    PubMed

    Rolland, Marine; Skov, Peter V; Larsen, Bodil K; Holm, Jørgen; Gómez-Requeni, Pedro; Dalsgaard, Johanne

    2016-08-01

    Strictly carnivorous fish with high requirements for dietary protein, such as rainbow trout (Oncorhynchus mykiss) are interesting models for studying the role of amino acids as key regulators of intermediary metabolism. Methionine is an essential amino acid for rainbow trout, and works as a signalling factor in different metabolic pathways. The study investigated the effect of increasing dietary methionine intake on the intermediary metabolism in the liver of juvenile rainbow trout. For this purpose, five diets were formulated with increasing methionine levels from 0.60 to 1.29% dry matter. The diets were fed in excess for six weeks before three sampling campaigns carried out successively to elucidate (i) the hepatic expression of selected genes involved in lipid, glucose and amino acid metabolism; (ii) the postprandial ammonia excretion; and (iii) the postprandial plasma methionine concentrations. The transcript levels of enzymes involved in lipid metabolism (fatty acid synthase, glucose 6 phosphate dehydrogenase and carnitine palmitoyl transferase 1 a), gluconeogenesis (fructose-1,6-biphosphatase) and amino acid catabolism (alanine amino transferase and glutamate dehydrogenase) were significantly affected by the increase in dietary methionine. Changes in gene expression reflected to some extent the decrease in ammonia excretion (P=0.022) and in the hepatosomatic index (HSI; P<0.001) when dietary methionine increased. Postprandial plasma methionine concentrations correlated positively with the dietary level (P<0.001) at the different sampling points. The study shows that the expression of several genes related to the hepatic intermediary metabolism in rainbow trout responded in a dose-dependent manner to increasing levels of dietary methionine.

  11. Increasing levels of dietary crystalline methionine affect plasma methionine profiles, ammonia excretion, and the expression of genes related to the hepatic intermediary metabolism in rainbow trout (Oncorhynchus mykiss).

    PubMed

    Rolland, Marine; Skov, Peter V; Larsen, Bodil K; Holm, Jørgen; Gómez-Requeni, Pedro; Dalsgaard, Johanne

    2016-08-01

    Strictly carnivorous fish with high requirements for dietary protein, such as rainbow trout (Oncorhynchus mykiss) are interesting models for studying the role of amino acids as key regulators of intermediary metabolism. Methionine is an essential amino acid for rainbow trout, and works as a signalling factor in different metabolic pathways. The study investigated the effect of increasing dietary methionine intake on the intermediary metabolism in the liver of juvenile rainbow trout. For this purpose, five diets were formulated with increasing methionine levels from 0.60 to 1.29% dry matter. The diets were fed in excess for six weeks before three sampling campaigns carried out successively to elucidate (i) the hepatic expression of selected genes involved in lipid, glucose and amino acid metabolism; (ii) the postprandial ammonia excretion; and (iii) the postprandial plasma methionine concentrations. The transcript levels of enzymes involved in lipid metabolism (fatty acid synthase, glucose 6 phosphate dehydrogenase and carnitine palmitoyl transferase 1 a), gluconeogenesis (fructose-1,6-biphosphatase) and amino acid catabolism (alanine amino transferase and glutamate dehydrogenase) were significantly affected by the increase in dietary methionine. Changes in gene expression reflected to some extent the decrease in ammonia excretion (P=0.022) and in the hepatosomatic index (HSI; P<0.001) when dietary methionine increased. Postprandial plasma methionine concentrations correlated positively with the dietary level (P<0.001) at the different sampling points. The study shows that the expression of several genes related to the hepatic intermediary metabolism in rainbow trout responded in a dose-dependent manner to increasing levels of dietary methionine. PMID:27105833

  12. Dietary folate and choline status differentially affect lipid metabolism and behavior-mediated neurotransmitters in young rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The relationship between choline and folate metabolisms is an important issue due to the essential role of these nutrients in brain plasticity and cognitive functions. Present study was designed to investigate whether modification of the dietary folate-choline status in young rats would affect brain...

  13. Calcium homeostasis and bone metabolic responses to protein diets and energy restriction: a randomized control trial

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite some beneficial effects on bone, high protein diets are conventionally considered a primary dietary risk factor for osteoporosis and bone fracture due to the acid load associated with protein catabolism. To test the hypothesis that high dietary protein diets do not negatively affect calcium ...

  14. The F-box protein COI1 functions upstream of MYB305 to regulate primary carbohydrate metabolism in tobacco (Nicotiana tabacum L. cv. TN90)

    PubMed Central

    Zhang, Hongbo

    2014-01-01

    Jasmonate (JA) plays an important role in regulating plant male fertility and secondary metabolism, but its role in regulating primary metabolism remains unclear. The F-box protein CORONATINE INSENSITIVE 1 (COI1) is a critical component of the JA receptor, and mediates JA-signalling by targeting JASMONATE ZIM-domain (JAZ) proteins for proteasomal degradation in response to JA perception. Here, we found that RNA interference-mediated knockdown of NtCOI1 in tobacco (Nicotiana tabacum L. cv. TN90) recapitulated many previously observed phenotypes in coi1 mutants, including male sterility, JA insensitivity, and loss of floral anthocyanin production. It also affected starch metabolism in the pollen, anther wall, and floral nectary, leading to pollen abortion and loss of floral nectar. Transcript levels of genes encoding starch metabolism enzymes were significantly altered in the pollen, anther wall, and floral nectary of NtCOI1-silenced tobacco. Changes in leaf primary metabolism were also observed in the NtCOI1-silenced tobacco. The expression of NtMYB305, an orthologue of MYB305 previously identified as a flavonoid metabolic regulator in Antirrhinum majus flowers and as a floral-nectar regulator mediating starch synthesis in ornamental tobacco, was extremely downregulated in NtCOI1-silenced tobacco. These findings suggest that NtCOI1 functions upstream of NtMYB305 and plays a fundamental role in coordinating plant primary carbohydrate metabolism and correlative physiological processes. PMID:24604735

  15. Pharmacokinetics, metabolism and distribution of PEGs and PEGylated proteins: quo vadis?

    PubMed

    Baumann, Andreas; Tuerck, Dietrich; Prabhu, Saileta; Dickmann, Leslie; Sims, Jennifer

    2014-10-01

    The pharmacokinetics (PK), metabolism and biodistribution of polyethylene glycol (PEG) in PEGylated proteins are important to understand the increased cellular vacuolation reported in various tissues in animals. The tissue distribution profile of PEGylated proteins and 'metabolic' PEG is guided largely by absolute PEG load, PEG molecular weight and, where applicable, receptor-mediated uptake via the protein moiety. High molecular weight PEGs show slow renal clearance, and consequently have a greater potential to accumulate within cells. The intracellular nonbiodegradable PEG can accumulate within the lysosome ultimately causing distension and vacuolation observed by standard histological examinations. Improved bioanalytical methodologies will contribute to the identification of specific PK parameters including distribution behavior to support development of PEGylated proteins as therapeutics.

  16. A sucrose transporter-interacting protein disulphide isomerase affects redox homeostasis and links sucrose partitioning with abiotic stress tolerance.

    PubMed

    Eggert, Erik; Obata, Toshihiro; Gerstenberger, Anne; Gier, Konstanze; Brandt, Tobias; Fernie, Alisdair R; Schulze, Waltraud; Kühn, Christina

    2016-06-01

    Sucrose accumulation in leaves in response to various abiotic stresses suggests a specific role of this disaccharide for stress tolerance and adaptation. The high-affinity transporter StSUT1 undergoes substrate-induced endocytosis presenting the question as to whether altered sucrose accumulation in leaves in response to stresses is also related to enhanced endocytosis or altered activity of the sucrose transporter. StSUT1 is known to interact with several stress-inducible proteins; here we investigated whether one of the interacting candidates, StPDI1, affects its subcellular localization in response to stress: StPDI1 expression is induced by ER-stress and salt. Both proteins, StSUT1 and StPDI1, were found in the detergent resistant membrane (DRM) fraction, and this might affect internalization. Knockdown of StPDI1 expression severely affects abiotic stress tolerance of transgenic potato plants. Analysis of these plants does not reveal modified subcellular localization or endocytosis of StSUT1, but rather a disturbed redox homeostasis, reduced detoxification of reactive oxygen species and effects on primary metabolism. Parallel observations with other StSUT1-interacting proteins are discussed. The redox status in leaves seems to be linked to the sugar status in response to various stress stimuli and to play a role in stress tolerance. PMID:26670204

  17. The effects of dietary protein and amino acids on skeletal metabolism.

    PubMed

    Bihuniak, Jessica D; Insogna, Karl L

    2015-07-15

    Dietary protein is required for optimal skeletal growth and maturation. Although Recommended Dietary Allowances (RDAs) exist for global dietary protein intake, the level and sources of dietary protein that are optimal for skeletal health over the life continuum have not been established. This is partly due to the difficulty in quantifying the effects of variable levels of a nutrient's intake over a lifetime as well as the complex nature of the relationships between dietary protein and calcium economy. Areas of current uncertainty include the precise source and amount of dietary protein required for optimal skeletal accretion and maintenance of skeletal mass, as well as the site-specific effects of dietary protein. The cellular and molecular mechanisms that underpin the actions of dietary protein on mineral metabolism and skeletal homeostasis remain unclear. This review attempts to summarize recent data bearing on these questions. PMID:25843057

  18. Prion protein polymorphisms affect chronic wasting disease progression.

    PubMed

    Johnson, Chad J; Herbst, Allen; Duque-Velasquez, Camilo; Vanderloo, Joshua P; Bochsler, Phil; Chappell, Rick; McKenzie, Debbie

    2011-01-01

    Analysis of the PRNP gene in cervids naturally infected with chronic wasting disease (CWD) suggested that PRNP polymorphisms affect the susceptibility of deer to infection. To test this effect, we orally inoculated 12 white-tailed deer with CWD agent. Three different PRNP alleles, wild-type (wt; glutamine at amino acid 95 and glycine at 96), Q95H (glutamine to histidine at amino acid position 95) and G96S (glycine to serine at position 96) were represented in the study cohort with 5 wt/wt, 3 wt/G96S, and 1 each wt/Q95H and Q95H/G96S. Two animals were lost to follow-up due to intercurrent disease. The inoculum was prepared from Wisconsin hunter-harvested homozygous wt/wt animals. All infected deer presented with clinical signs of CWD; the orally infected wt/wt had an average survival period of 693 days post inoculation (dpi) and G96S/wt deer had an average survival period of 956 dpi. The Q95H/wt and Q95H/G96S deer succumbed to CWD at 1,508 and 1,596 dpi respectively. These data show that polymorphisms in the PRNP gene affect CWD incubation period. Deer heterozygous for the PRNP alleles had extended incubation periods with the Q95H allele having the greatest effect.

  19. Weight, protein, fat, and timing of preloads affect food intake.

    PubMed

    Porrini, M; Santangelo, A; Crovetti, R; Riso, P; Testolin, G; Blundell, J E

    1997-09-01

    Two foods, one rich in protein (HP) and one rich in fat (HF), were employed to evaluate the effect of macronutrients on food intake and to underline the differences that occurred when the foods were served as uniform meal, as first course of a varied meal, and as a snack 2 h before a varied meal. Our results showed that HP food always exerted a higher effect on both intrameal satiation and postingestive satiety than HF food. When a uniform meal was consumed, satiation for the specific food was reached before fullness; in this condition, sensory characteristics of foods played an important role in controlling food intake and made the uniform meal more satiating than the varied one. The consumption of a snack far from a meal did not contribute to satiety; consequently, gastric filling seems to be an important factor determining the amount consumed in a varied meal.

  20. Amino acid metabolism, substrate availability and the control of protein dynamics in the human kidney.

    PubMed

    Garibotto, G; Tessari, P; Sacco, P; Deferrari, G

    1999-01-01

    The mechanisms controlling protein metabolism in the human kidney are not well understood. During adult life, kidney protein content and the size of the kidney remain fairly constant, indicating that protein synthesis and degradation within the kidney are tightly regulated. However, kidney protein turnover may change in response to stimuli such as alterations in substrate availability, hormones or growth factors, acid-base balance, renal work or renal injury with a progressive decrease in the number of nephrons. These factors have been evaluated mainly in animals, in vitro or in vivo. Amino acids, the kidneys substrates for protein synthesis, are provided by several routes. Like in other organs, amino acids can reach the kidney cells through the arterial blood flow. However, they may also come from the degradation of reabsorbed low-molecular weight proteins filtered by the glomerulus. The human kidney has high rates of protein turnover and leucine oxidation. The magnitude of the protein turnover across the human kidney suggests that the protein dynamics is partly determined by intrarenal protein catabolism. As evaluated by a steady-state leucine multiple compartment analysis, kidney protein synthesis is dependent to a similar extent on intrarenal generation of amino acids from protein breakdown and from amino acids taken up from the arterial blood. Kidney mass may therefore depend not only on the availability of free amino acids, but also on filtered proteins which are degraded within the kidney. Future studies could define the mechanisms, metabolic pathways and mediators influencing kidney protein turnover in humans, with a view to better comprehension of the mechanisms of disease. PMID:10493563

  1. Protein phosphorylation and prevention of cytochrome oxidase inhibition by ATP: coupled mechanisms of energy metabolism regulation.

    PubMed

    Acin-Perez, Rebeca; Gatti, Domenico L; Bai, Yidong; Manfredi, Giovanni

    2011-06-01

    Rapid regulation of oxidative phosphorylation is crucial for mitochondrial adaptation to swift changes in fuels availability and energy demands. An intramitochondrial signaling pathway regulates cytochrome oxidase (COX), the terminal enzyme of the respiratory chain, through reversible phosphorylation. We find that PKA-mediated phosphorylation of a COX subunit dictates mammalian mitochondrial energy fluxes and identify the specific residue (S58) of COX subunit IV-1 (COXIV-1) that is involved in this mechanism of metabolic regulation. Using protein mutagenesis, molecular dynamics simulations, and induced fit docking, we show that mitochondrial energy metabolism regulation by phosphorylation of COXIV-1 is coupled with prevention of COX allosteric inhibition by ATP. This regulatory mechanism is essential for efficient oxidative metabolism and cell survival. We propose that S58 COXIV-1 phosphorylation has evolved as a metabolic switch that allows mammalian mitochondria to rapidly toggle between energy utilization and energy storage.

  2. Role of the mixed-lineage protein kinase pathway in the metabolic stress response to obesity

    PubMed Central

    Kant, Shashi; Barrett, Tamera; Vertii, Anastassiia; Noh, Yun Hee; Jung, Dae Young; Kim, Jason K.; Davis, Roger J.

    2013-01-01

    Summary Saturated free fatty acid (FFA) is implicated in the metabolic response to obesity. In vitro studies indicate that FFA signaling may be mediated by the mixed-lineage protein kinase (MLK) pathway that activates cJun NH2-terminal kinase (JNK). Here we examined the role of the MLK pathway in vivo using a mouse model of diet-induced obesity. The ubiquitously expressed MLK2 and MLK3 protein kinases have partially redundant functions. We therefore compared wild-type and compound mutant mice that lack expression of MLK2 plus MLK3. MLK-deficiency protected mice against high fat diet-induced insulin resistance and obesity. Reduced JNK activation and increased energy expenditure contribute to the metabolic effects of MLK-deficiency. These data confirm that the MLK pathway plays a critical role in the metabolic response to obesity. PMID:23954791

  3. Sarcocystis fusiformis: some protein metabolic enzymes in various fractions of sarcocysts of buffalo (Bubalus bubalis).

    PubMed

    Gupta, R S; Kushwah, H S; Kushwah, A

    1993-01-01

    An investigation on the relative presence of some protein metabolic enzymes, namely aspartate aminotransferase (AST), alanine aminotransferase (ALT), NAD+ and NADP+ dependent glutamate dehydrogenase (GLDH) and arginase in cyst wall (CW), cyst fluid (CF) and zoite (ZT) fractions of the sarcocysts of Sarcocystis fusiformis in the oesophageal muscles of Indian water buffalo was carried out. Both the transaminases were present in all the fractions of the cyst, although in variable amounts. There was a higher level of AST activity than of ALT activity. AST activity was the highest in ZT, whereas ALT activity was at a maximum in the CF fraction. The levels of activity of NAD+ and NADP+ dependent GLDH and arginase remained beyond detectable limits. The study revealed that the intermediates of carbohydrate metabolism are linked to protein metabolism by transaminases. The possibility of concomitant removal of ammonia and its subsequent incorporation into the urea cycle is ruled out in this parasitic protozoan.

  4. Regulatory mechanism of protein metabolic pathway during the differentiation process of chicken male germ cell.

    PubMed

    Li, Dong; Zuo, Qisheng; Lian, Chao; Zhang, Lei; Shi, Qingqing; Zhang, Zhentao; Wang, Yingjie; Ahmed, Mahmoud F; Tang, Beibei; Xiao, Tianrong; Zhang, Yani; Li, Bichun

    2015-08-01

    We explored the regulatory mechanism of protein metabolism during the differentiation process of chicken male germ cells and provide a basis for improving the induction system of embryonic stem cell differentiation to male germ cells in vitro. We sequenced the transcriptome of embryonic stem cells, primordial germ cells, and spermatogonial stem cells with RNA sequencing (RNA-Seq), bioinformatics analysis methods, and detection of the key genes by quantitative reverse transcription PCR (qRT-PCR). Finally, we found 16 amino acid metabolic pathways enriched in the biological metabolism during the differentiation process of embryonic stem cells to primordial germ cells and 15 amino acid metabolic pathways enriched in the differentiation stage of primordial germ cells to spermatogonial stem cells. We found three pathways, arginine-proline metabolic pathway, tyrosine metabolic pathway, and tryptophan metabolic pathway, significantly enriched in the whole differentiation process of embryonic stem cells to spermatogonial stem cells. Moreover, for these three pathways, we screened key genes such as NOS2, ADC, FAH, and IDO. qRT-PCR results showed that the expression trend of these genes were the same to RNA-Seq. Our findings showed that the three pathways and these key genes play an important role in the differentiation process of embryonic stem cells to male germ cells. These results provide basic information for improving the induction system of embryonic stem cell differentiation to male germ cells in vitro.

  5. [Protein metabolism in the cerebral hemispheres during the emotional-algesic stress].

    PubMed

    Yakushev, V S; Davydov, V V; Bushueva, V V; Skurygin, V P; Krisanova, N V

    1985-01-01

    Emotional-algesic stress causes essential changes in the protein metabolism of cerebral hemispheres. These changes may be of great importance for the functioning of the brain and cause the disturbances of the higher nervous activity when the organism is influenced by the emotional stress factors. PMID:4039861

  6. Metabolic responses to nocturnal eating in men are affected by sources of dietary energy.

    PubMed

    Holmbäck, Ulf; Forslund, Anders; Forslund, Jeanette; Hambraeus, Leif; Lennernäs, Maria; Lowden, Arne; Stridsberg, Mats; Akerstedt, Torbjörn

    2002-07-01

    Because night work is becoming more prevalent, we studied whether feeding at different times of a 24-h period would elicit different metabolic responses and whether dietary macronutrient composition would affect these responses. Seven men (26-43 y, 19.9-26.6 kg/m(2)) consumed two isocaloric diets, in a crossover design. The diets were a high carbohydrate (HC) diet [65 energy % (E%) carbohydrates, 20E% fat] and a high fat (HF) diet (40E% carbohydrates, 45E% fat). After a 6-d diet-adjustment period, the men were kept awake for 24 h and the food (continuation of respective diet) was provided as six isocaloric meals (i.e., every 4 h). Energy and substrate turnover, heart rate, mean arterial pressure (MAP), blood glucose, triacylglycerol (TAG), nonesterified fatty acid (NEFA) and glycerol were measured throughout the 24-h period. Significantly higher energy expenditure and NEFA concentration, and lower blood glucose and TAG concentrations were observed when the men consumed the HF diet than when they consumed the HC diet. Significant circadian patterns were seen in body and skin temperature (nadir, 0400-0500 h). When the men consumed the HF diet, significant circadian patterns were seen in fat oxidation (nadir, 0800-1200 h; plateau, 1200-0800 h), heat release (nadir, 0800-1200 h; plateau, 1600-0800 h), heart rate (nadir, 0000 h), blood glucose (nadir, 0800-1200 h; peak, 0000-0400 h), NEFA (nadir, 0800-1200 h; peak, 1200-2000 h) and TAG (nadir, 0800-1200 h; peak, 0400-0800 h) concentrations. Energy expenditure, carbohydrate oxidation, MAP and glycerol concentration did not display circadian patterns. Unequal variances eradicated most circadian effects in the HC-diet data. The increased TAG concentration in response to feeding at 0400 h might be involved in the higher TAG concentrations seen in shift workers. Distinct macronutrient/circadian-dependent postprandial responses were seen in most studied variables.

  7. Metabolic stressors and signals differentially affect energy allocation between reproduction and immune function.

    PubMed

    Carlton, Elizabeth D; Cooper, Candace L; Demas, Gregory E

    2014-11-01

    Most free-living animals have finite energy stores that they must allocate to different physiological and behavioral processes. In times of energetic stress, trade-offs in energy allocation among these processes may occur. The manifestation of trade-offs may depend on the source (e.g., glucose, lipids) and severity of energy limitation. In this study, we investigated energetic trade-offs between the reproductive and immune systems by experimentally limiting energy availability to female Siberian hamsters (Phodopus sungorus) with 2-deoxy-d-glucose, a compound that disrupts cellular utilization of glucose. We observed how glucoprivation at two levels of severity affected allocation to reproduction and immunity. Additionally, we treated a subset of these hamsters with leptin, an adipose hormone that provides a direct signal of available fat stores, in order to determine how increasing this signal of fat stores influences glucoprivation-induced trade-offs. We observed trade-offs between the reproductive and immune systems and that these trade-offs depended on the severity of energy limitation and exogenous leptin signaling. The majority of the animals experiencing mild glucoprivation entered anestrus, whereas leptin treatment restored estrous cycling in these animals. Surprisingly, virtually all animals experiencing more severe glucoprivation maintained normal estrous cycling throughout the experiment; however, exogenous leptin resulted in lower antibody production in this group. These data suggest that variation in these trade-offs may be mediated by shifts between glucose and fatty acid utilization. Collectively, the results of the present study highlight the context-dependent nature of these trade-offs, as trade-offs induced by the same metabolic stressor can manifest differently depending on its intensity.

  8. Host-related metabolic cues affect colonization strategies of a root endophyte

    PubMed Central

    Lahrmann, Urs; Ding, Yi; Banhara, Aline; Rath, Magnus; Hajirezaei, Mohammad R.; Döhlemann, Stefanie; von Wirén, Nicolaus; Parniske, Martin; Zuccaro, Alga

    2013-01-01

    The mechanisms underpinning broad compatibility in root symbiosis are largely unexplored. The generalist root endophyte Piriformospora indica establishes long-lasting interactions with morphologically and biochemically different hosts, stimulating their growth, alleviating salt stress, and inducing local and systemic resistance to pathogens. Cytological studies and global investigations of fungal transcriptional responses to colonization of barley and Arabidopsis at different symbiotic stages identified host-dependent colonization strategies and host-specifically induced effector candidates. Here, we show that in Arabidopsis, P. indica establishes and maintains biotrophic nutrition within living epidermal cells, whereas in barley the symbiont undergoes a nutritional switch to saprotrophy that is associated with the production of secondary thinner hyphae in dead cortex cells. Consistent with a diversified trophic behavior and with the occurrence of nitrogen deficiency at the onset of saprotrophy in barley, fungal genes encoding hydrolytic enzymes and nutrient transporters were highly induced in this host but not in Arabidopsis. Silencing of the high-affinity ammonium transporter PiAMT1 gene, whose transcripts are accumulating during nitrogen starvation and in barley, resulted in enhanced colonization of this host, whereas it had no effect on the colonization of Arabidopsis. Increased levels of free amino acids and reduced enzymatic activity for the cell-death marker VPE (vacuolar-processing enzyme) in colonized barley roots coincided with an extended biotrophic lifestyle of P. indica upon silencing of PiAMT1. This suggests that PiAmt1 functions as a nitrogen sensor mediating the signal that triggers the in planta activation of the saprotrophic program. Thus, host-related metabolic cues affect the expression of P. indica’s alternative lifestyles. PMID:23918389

  9. Metabolic responses to nocturnal eating in men are affected by sources of dietary energy.

    PubMed

    Holmbäck, Ulf; Forslund, Anders; Forslund, Jeanette; Hambraeus, Leif; Lennernäs, Maria; Lowden, Arne; Stridsberg, Mats; Akerstedt, Torbjörn

    2002-07-01

    Because night work is becoming more prevalent, we studied whether feeding at different times of a 24-h period would elicit different metabolic responses and whether dietary macronutrient composition would affect these responses. Seven men (26-43 y, 19.9-26.6 kg/m(2)) consumed two isocaloric diets, in a crossover design. The diets were a high carbohydrate (HC) diet [65 energy % (E%) carbohydrates, 20E% fat] and a high fat (HF) diet (40E% carbohydrates, 45E% fat). After a 6-d diet-adjustment period, the men were kept awake for 24 h and the food (continuation of respective diet) was provided as six isocaloric meals (i.e., every 4 h). Energy and substrate turnover, heart rate, mean arterial pressure (MAP), blood glucose, triacylglycerol (TAG), nonesterified fatty acid (NEFA) and glycerol were measured throughout the 24-h period. Significantly higher energy expenditure and NEFA concentration, and lower blood glucose and TAG concentrations were observed when the men consumed the HF diet than when they consumed the HC diet. Significant circadian patterns were seen in body and skin temperature (nadir, 0400-0500 h). When the men consumed the HF diet, significant circadian patterns were seen in fat oxidation (nadir, 0800-1200 h; plateau, 1200-0800 h), heat release (nadir, 0800-1200 h; plateau, 1600-0800 h), heart rate (nadir, 0000 h), blood glucose (nadir, 0800-1200 h; peak, 0000-0400 h), NEFA (nadir, 0800-1200 h; peak, 1200-2000 h) and TAG (nadir, 0800-1200 h; peak, 0400-0800 h) concentrations. Energy expenditure, carbohydrate oxidation, MAP and glycerol concentration did not display circadian patterns. Unequal variances eradicated most circadian effects in the HC-diet data. The increased TAG concentration in response to feeding at 0400 h might be involved in the higher TAG concentrations seen in shift workers. Distinct macronutrient/circadian-dependent postprandial responses were seen in most studied variables. PMID:12097665

  10. Temperature-induced elevation of basal metabolic rate does not affect testis growth in great tits.

    PubMed

    Caro, Samuel P; Visser, Marcel E

    2009-07-01

    The timing of reproduction varies from year to year in many bird species. To adjust their timing to the prevailing conditions of that year, birds use cues from their environment. However, the relative importance of these cues, such as the initial predictive (e.g. photoperiod) and the supplemental factors (e.g. temperature), on the seasonal sexual development are difficult to distinguish. In particular, the fine-tuning effect of temperature on gonadal growth is not well known. One way temperature may affect timing is via its strong effect on energy expenditure as gonadal growth is an energy-demanding process. To study the interaction of photoperiod and temperature on gonadal development, we first exposed 35 individually housed male great tits (Parus major) to mid-long days (after 6 weeks of 8 h L:16 h D at 15 degrees C, photoperiod was set to 13 h L:11 h D at 15 degrees C). Two weeks later, for half of the males the temperature was set to 8 degrees C, and for the other half to 22 degrees C. Unilateral laparotomies were performed at weeks 5 (i.e one week before the birds were transferred to mid-long days), 8 and 11 to measure testis size. Two measures of basal metabolic rate (BMR) were performed at the end of the experiment (weeks 11 and 12). Testis size increased significantly during the course of the experiment, but independently of the temperature treatment. BMR was significantly higher in birds exposed to the cold treatment. These results show that temperature-related elevation of BMR did not impair the long-day-induced testis growth in great tits. As a consequence, temperature may not be a crucial cue and/or constraint factor in the fine-tuning of the gonadal recrudescence in male great tits, and testis growth is not a high energy-demanding seasonal process. PMID:19525424

  11. Darwinian and demographic forces affecting human protein coding genes

    PubMed Central

    Nielsen, Rasmus; Hubisz, Melissa J.; Hellmann, Ines; Torgerson, Dara; Andrés, Aida M.; Albrechtsen, Anders; Gutenkunst, Ryan; Adams, Mark D.; Cargill, Michele; Boyko, Adam; Indap, Amit; Bustamante, Carlos D.; Clark, Andrew G.

    2009-01-01

    Past demographic changes can produce distortions in patterns of genetic variation that can mimic the appearance of natural selection unless the demographic effects are explicitly removed. Here we fit a detailed model of human demography that incorporates divergence, migration, admixture, and changes in population size to directly sequenced data from 13,400 protein coding genes from 20 European-American and 19 African-American individuals. Based on this demographic model, we use several new and established statistical methods for identifying genes with extreme patterns of polymorphism likely to be caused by Darwinian selection, providing the first genome-wide analysis of allele frequency distributions in humans based on directly sequenced data. The tests are based on observations of excesses of high frequency–derived alleles, excesses of low frequency–derived alleles, and excesses of differences in allele frequencies between populations. We detect numerous new genes with strong evidence of selection, including a number of genes related to psychiatric and other diseases. We also show that microRNA controlled genes evolve under extremely high constraints and are more likely to undergo negative selection than other genes. Furthermore, we show that genes involved in muscle development have been subject to positive selection during recent human history. In accordance with previous studies, we find evidence for negative selection against mutations in genes associated with Mendelian disease and positive selection acting on genes associated with several complex diseases. PMID:19279335

  12. Water deficit alters differentially metabolic pathways affecting important flavor and quality traits in grape berries of Cabernet Sauvignon and Chardonnay

    PubMed Central

    Deluc, Laurent G; Quilici, David R; Decendit, Alain; Grimplet, Jérôme; Wheatley, Matthew D; Schlauch, Karen A; Mérillon, Jean-Michel; Cushman, John C; Cramer, Grant R

    2009-01-01

    Background Water deficit has significant effects on grape berry composition resulting in improved wine quality by the enhancement of color, flavors, or aromas. While some pathways or enzymes affected by water deficit have been identified, little is known about the global effects of water deficit on grape berry metabolism. Results The effects of long-term, seasonal water deficit on berries of Cabernet Sauvignon, a red-wine grape, and Chardonnay, a white-wine grape were analyzed by integrated transcript and metabolite profiling. Over the course of berry development, the steady-state transcript abundance of approximately 6,000 Unigenes differed significantly between the cultivars and the irrigation treatments. Water deficit most affected the phenylpropanoid, ABA, isoprenoid, carotenoid, amino acid and fatty acid metabolic pathways. Targeted metabolites were profiled to confirm putative changes in specific metabolic pathways. Water deficit activated the expression of numerous transcripts associated with glutamate and proline biosynthesis and some committed steps of the phenylpropanoid pathway that increased anthocyanin concentrations in Cabernet Sauvignon. In Chardonnay, water deficit activated parts of the phenylpropanoid, energy, carotenoid and isoprenoid metabolic pathways that contribute to increased concentrations of antheraxanthin, flavonols and aroma volatiles. Water deficit affected the ABA metabolic pathway in both cultivars. Berry ABA concentrations were highly correlated with 9-cis-epoxycarotenoid dioxygenase (NCED1) transcript abundance, whereas the mRNA expression of other NCED genes and ABA catabolic and glycosylation processes were largely unaffected. Water deficit nearly doubled ABA concentrations within berries of Cabernet Sauvignon, whereas it decreased ABA in Chardonnay at véraison and shortly thereafter. Conclusion The metabolic responses of grapes to water deficit varied with the cultivar and fruit pigmentation. Chardonnay berries, which lack any

  13. Intein Applications: From Protein Purification and Labeling to Metabolic Control Methods*

    PubMed Central

    Wood, David W.; Camarero, Julio A.

    2014-01-01

    The discovery of inteins in the early 1990s opened the door to a wide variety of new technologies. Early engineered inteins from various sources allowed the development of self-cleaving affinity tags and new methods for joining protein segments through expressed protein ligation. Some applications were developed around native and engineered split inteins, which allow protein segments expressed separately to be spliced together in vitro. More recently, these early applications have been expanded and optimized through the discovery of highly efficient trans-splicing and trans-cleaving inteins. These new inteins have enabled a wide variety of applications in metabolic engineering, protein labeling, biomaterials construction, protein cyclization, and protein purification. PMID:24700459

  14. Depletion of the "gamma-type carbonic anhydrase-like" subunits of complex I affects central mitochondrial metabolism in Arabidopsis thaliana.

    PubMed

    Fromm, Steffanie; Göing, Jennifer; Lorenz, Christin; Peterhänsel, Christoph; Braun, Hans-Peter

    2016-01-01

    "Gamma-type carbonic anhydrase-like" (CAL) proteins form part of complex I in plants. Together with "gamma carbonic anhydrase" (CA) proteins they form an extra domain which is attached to the membrane arm of complex I on its matrix exposed side. In Arabidopsis two CAL and three CA proteins are present, termed CAL1, CAL2, CA1, CA2 and CA3. It has been proposed that the carbonic anhydrase domain of complex I is involved in a process mediating efficient recycling of mitochondrial CO2 for photosynthetic carbon fixation which is especially important during growth conditions causing increased photorespiration. Depletion of CAL proteins has been shown to significantly affect plant development and photomorphogenesis. To better understand CAL function in plants we here investigated effects of CAL depletion on the mitochondrial compartment. In mutant lines and cell cultures complex I amount was reduced by 90-95% but levels of complexes III and V were unchanged. At the same time, some of the CA transcripts were less abundant. Proteome analysis of CAL depleted cells revealed significant reduction of complex I subunits as well as proteins associated with photorespiration, but increased amounts of proteins participating in amino acid catabolism and stress response reactions. Developmental delay of the mutants was slightly alleviated if plants were cultivated at high CO2. Profiling of selected metabolites revealed defined changes in intermediates of the citric acid cycle and amino acid catabolism. It is concluded that CAL proteins are essential for complex I assembly and that CAL depletion specifically affects central mitochondrial metabolism.

  15. Hybrid metabolic flux analysis and recombinant protein prediction in Pichia pastoris X-33 cultures expressing a single-chain antibody fragment.

    PubMed

    Isidro, Inês A; Portela, Rui M; Clemente, João J; Cunha, António E; Oliveira, Rui

    2016-09-01

    Despite the growing importance of the Pichia pastoris expression system as industrial workhorse, the literature is almost absent in systematic studies on how culture medium composition affects central carbon fluxes and heterologous protein expression. In this study we investigate how 26 variations of the BSM+PTM1 medium impact central carbon fluxes and protein expression in a P. pastoris X-33 strain expressing a single-chain antibody fragment. To achieve this goal, we adopted a hybrid metabolic flux analysis (MFA) methodology, which is a modification of standard MFA to predict the rate of synthesis of recombinant proteins. Hybrid MFA combines the traditional parametric estimation of central carbon fluxes with non-parametric statistical modeling of product-related quantitative or qualitative measurements as a function of central carbon fluxes. It was observed that protein yield variability was 53.6 % (relative standard deviation) among the different experiments. Protein yield is much more sensitive to medium composition than biomass growth, which is mainly determined by the carbon source availability and main salts. Hybrid MFA was able to describe accurately the protein yield with normalized RMSE of 6.3 % over 5 independent experiments. The metabolic state that promotes high protein yields is characterized by high overall metabolic rates through main central carbon pathways concomitantly with a relative shift of carbon flux from biosynthetic towards energy generating pathways. PMID:27129458

  16. Metabolism

    MedlinePlus

    Metabolism refers to all the physical and chemical processes in the body that convert or use energy, ... Tortora GJ, Derrickson BH. Metabolism. In: Tortora GJ, Derrickson BH. Principles of Anatomy and Physiology . 14th ed. Hoboken, NJ: John H Wiley and Sons; 2013: ...

  17. Cytochromes and iron sulfur proteins in sulfur metabolism of phototrophic bacteria

    NASA Technical Reports Server (NTRS)

    Fischer, U.

    1985-01-01

    Dissimilatory sulfur metabolism in phototrophic sulfur bacteria provides the bacteria with electrons for photosynthetic electron transport chain and, with energy. Assimilatory sulfate reduction is necessary for the biosynthesis of sulfur-containing cell components. Sulfide, thiosulfate, and elemental sulfur are the sulfur compounds most commonly used by phototrophic bacteria as electron donors for anoxygenic photosynthesis. Cytochromes or other electron transfer proteins, like high-potential-iron-sulfur protein (HIPIP) function as electron acceptors or donors for most enzymatic steps during the oxidation pathways of sulfide or thiosulfate. Yet, heme- or siroheme-containing proteins themselves undergo enzymatic activities in sulfur metabolism. Sirohemes comprise a porphyrin-like prosthetic group of sulfate reductase. eenzymatic reactions involve electron transfer. Electron donors or acceptors are necessary for each reaction. Cytochromes and iron sulfur problems, are able to transfer electrons.

  18. Deficiency of PdxR in Streptococcus mutans affects vitamin B6 metabolism, acid tolerance response and biofilm formation.

    PubMed

    Liao, S; Bitoun, J P; Nguyen, A H; Bozner, D; Yao, X; Wen, Z T

    2015-08-01

    Streptococcus mutans, a key etiological agent of the human dental caries, lives primarily on the tooth surface in tenacious biofilms. The SMU864 locus, designated pdxR, is predicted to encode a member of the novel MocR/GabR family proteins, which are featured with a winged helix DNA-binding N-terminal domain and a C-terminal domain highly homologous to the pyridoxal phosphate-dependent aspartate aminotransferases. A pdxR-deficient mutant, TW296, was constructed using allelic exchange. PdxR deficiency in S. mutans had little effect on cell morphology and growth when grown in brain heart infusion. However, when compared with its parent strain, UA159, the PdxR-deficient mutant displayed major defects in acid tolerance response and formed significantly fewer biofilms (P < 0.01). When analyzed by real-time polymerase chain reaction, PdxR deficiency was found to drastically reduce expression of an apparent operon encoding a pyridoxal kinase (SMU865) and a pyridoxal permease (SMU866) of the salvage pathway of vitamin B6 biosynthesis. In addition, PdxR deficiency also altered the expression of genes for ClpL protease, glucosyltransferase B and adhesin SpaP, which are known to play important roles in stress tolerance and biofilm formation. Consistently, PdxR-deficiency affected the growth of the deficient mutant when grown in defined medium with and without vitamin B6 . Further studies revealed that although S. mutans is known to require vitamin B6 to grow in defined medium, B6 vitamers, especially pyridoxal, were strongly inhibitory at millimolar concentrations, against S. mutans growth and biofilm formation. Our results suggest that PdxR in S. mutans plays an important role in regulation of vitamin B6 metabolism, acid tolerance response and biofilm formation. PMID:25421565

  19. Deficiency of PdxR in Streptococcus mutans affects vitamin B6 metabolism, acid tolerance response and biofilm formation.

    PubMed

    Liao, S; Bitoun, J P; Nguyen, A H; Bozner, D; Yao, X; Wen, Z T

    2015-08-01

    Streptococcus mutans, a key etiological agent of the human dental caries, lives primarily on the tooth surface in tenacious biofilms. The SMU864 locus, designated pdxR, is predicted to encode a member of the novel MocR/GabR family proteins, which are featured with a winged helix DNA-binding N-terminal domain and a C-terminal domain highly homologous to the pyridoxal phosphate-dependent aspartate aminotransferases. A pdxR-deficient mutant, TW296, was constructed using allelic exchange. PdxR deficiency in S. mutans had little effect on cell morphology and growth when grown in brain heart infusion. However, when compared with its parent strain, UA159, the PdxR-deficient mutant displayed major defects in acid tolerance response and formed significantly fewer biofilms (P < 0.01). When analyzed by real-time polymerase chain reaction, PdxR deficiency was found to drastically reduce expression of an apparent operon encoding a pyridoxal kinase (SMU865) and a pyridoxal permease (SMU866) of the salvage pathway of vitamin B6 biosynthesis. In addition, PdxR deficiency also altered the expression of genes for ClpL protease, glucosyltransferase B and adhesin SpaP, which are known to play important roles in stress tolerance and biofilm formation. Consistently, PdxR-deficiency affected the growth of the deficient mutant when grown in defined medium with and without vitamin B6 . Further studies revealed that although S. mutans is known to require vitamin B6 to grow in defined medium, B6 vitamers, especially pyridoxal, were strongly inhibitory at millimolar concentrations, against S. mutans growth and biofilm formation. Our results suggest that PdxR in S. mutans plays an important role in regulation of vitamin B6 metabolism, acid tolerance response and biofilm formation.

  20. Altered Arginine Metabolism in Cells Transfected with Human Wild-Type Beta Amyloid Precursor Protein (βAPP).

    PubMed

    Jęśko, Henryk; Wilkaniec, Anna; Cieślik, Magdalena; Hilgier, Wojciech; Gąssowska, Magdalena; Lukiw, Walter J; Adamczyk, Agata

    2016-01-01

    Alterations of enzymes linked to arginine metabolism have been recently implicated in Alzheimer's disease (AD). Despite strong association of arginine changes with nitric oxide (NO) pathway, the impact of amyloid β (Aβ) peptides on arginine degradation and re-synthesis is unknown. In the present study we compared expression levels of arginases (ARG1, ARG2), neuronal, endothelial and inducible NO synthase isoforms (NNOS, ENOS, INOS), enzymes that metabolize arginine or resynthesize it from citrulline and the levels of corresponding amino acids in rat pheochromocytoma (PC12) cells overexpressing human Aβ precursor protein (APPwt cells). Moreover, we investigated the changes in miRNAs responsible for modulation of arginine metabolism in AD brains. Real-time PCR analysis revealed in APPwt cells significant decreases of ARG1 and ARG2 which are responsible for lysing arginine into ornithine and urea; this reduction was followed by significantly lower enzyme activity. NNOS and ENOS mRNAs were elevated in APPwt cells while iNOS was undetectable in both cell lines. The expression of argininosuccinate synthase (ASS) that metabolizes citrulline was down-regulated without changes in argininosuccinate lyase (ASL). Ornithine decarboxylase (ODC), which decarboxylates ornithine to form putrescine was also reduced. Arginine, the substrate for both arginases and NOS, was unchanged in APPwt cells. However, citrulline concentration was significantly higher. Elevated miRNA-9 and miRNA-128a found in AD brain tissues might modulate the expression of ASS and NOS, respectively. Our results indicate that Aβ affects arginine metabolism and this influence might have important role in the pathomechanism of AD.

  1. Altered Arginine Metabolism in Cells Transfected with Human Wild-Type Beta Amyloid Precursor Protein (βAPP).

    PubMed

    Jęśko, Henryk; Wilkaniec, Anna; Cieślik, Magdalena; Hilgier, Wojciech; Gąssowska, Magdalena; Lukiw, Walter J; Adamczyk, Agata

    2016-01-01

    Alterations of enzymes linked to arginine metabolism have been recently implicated in Alzheimer's disease (AD). Despite strong association of arginine changes with nitric oxide (NO) pathway, the impact of amyloid β (Aβ) peptides on arginine degradation and re-synthesis is unknown. In the present study we compared expression levels of arginases (ARG1, ARG2), neuronal, endothelial and inducible NO synthase isoforms (NNOS, ENOS, INOS), enzymes that metabolize arginine or resynthesize it from citrulline and the levels of corresponding amino acids in rat pheochromocytoma (PC12) cells overexpressing human Aβ precursor protein (APPwt cells). Moreover, we investigated the changes in miRNAs responsible for modulation of arginine metabolism in AD brains. Real-time PCR analysis revealed in APPwt cells significant decreases of ARG1 and ARG2 which are responsible for lysing arginine into ornithine and urea; this reduction was followed by significantly lower enzyme activity. NNOS and ENOS mRNAs were elevated in APPwt cells while iNOS was undetectable in both cell lines. The expression of argininosuccinate synthase (ASS) that metabolizes citrulline was down-regulated without changes in argininosuccinate lyase (ASL). Ornithine decarboxylase (ODC), which decarboxylates ornithine to form putrescine was also reduced. Arginine, the substrate for both arginases and NOS, was unchanged in APPwt cells. However, citrulline concentration was significantly higher. Elevated miRNA-9 and miRNA-128a found in AD brain tissues might modulate the expression of ASS and NOS, respectively. Our results indicate that Aβ affects arginine metabolism and this influence might have important role in the pathomechanism of AD. PMID:26971935

  2. Effects of dairy protein and fat on the metabolic syndrome and type 2 diabetes.

    PubMed

    Bjørnshave, Ann; Hermansen, Kjeld

    2014-01-01

    The incidence of the metabolic syndrome (MetS) and type 2 diabetes (T2D) is increasing worldwide. Evidence supports a negative relationship between the consumption of dairy products and risk of MetS and T2D. Dairy proteins are known to have a directly beneficial effect on hypertension, dyslipidemia, and hyperglycemia, but a detailed understanding of the underlying mechanisms is missing. It has been confirmed by observations that the insulinotropic effect of dairy proteins is associated with the amino acid composition; in particular branched-chain amino acids (BCAA) seem to be of vital importance. Dairy protein-derived peptides may also contribute to the insulinotropic effect via dipeptidyl peptidase-4 (DPP-4) inhibitory activity, and may lower the blood pressure (BP). The lipid metabolism may be improved by whey protein (WP), which acts to reduce the postprandial triglyceride (TG) response. The effect of dairy fat is much more controversial because of the potentially harmful effect exerted by saturated fatty acid (SFA) on metabolic health. Recent observations suggest less adverse effects of SFA on metabolic health than previous assumed. However, little is known about dairy lipid fractions belonging to the groups of monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), and phospholipids (PL). Dairy fat seems to act differently depending on the dairy product and the composition of macronutrients in the meal. Therefore, for a better understanding of the mechanisms behind the dairy protein and fat effect on MetS, we suggest that more human studies should be carried out to clarify the interactions of dairy protein and fat with macronutrients in the meal and other dairy components, such as micronutrients and microorganisms from fermented products.

  3. Effects of Dairy Protein and Fat on the Metabolic Syndrome and Type 2 Diabetes

    PubMed Central

    Bjørnshave, Ann; Hermansen, Kjeld

    2014-01-01

    The incidence of the metabolic syndrome (MetS) and type 2 diabetes (T2D) is increasing worldwide. Evidence supports a negative relationship between the consumption of dairy products and risk of MetS and T2D. Dairy proteins are known to have a directly beneficial effect on hypertension, dyslipidemia, and hyperglycemia, but a detailed understanding of the underlying mechanisms is missing. It has been confirmed by observations that the insulinotropic effect of dairy proteins is associated with the amino acid composition; in particular branched-chain amino acids (BCAA) seem to be of vital importance. Dairy protein-derived peptides may also contribute to the insulinotropic effect via dipeptidyl peptidase-4 (DPP-4) inhibitory activity, and may lower the blood pressure (BP). The lipid metabolism may be improved by whey protein (WP), which acts to reduce the postprandial triglyceride (TG) response. The effect of dairy fat is much more controversial because of the potentially harmful effect exerted by saturated fatty acid (SFA) on metabolic health. Recent observations suggest less adverse effects of SFA on metabolic health than previous assumed. However, little is known about dairy lipid fractions belonging to the groups of monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), and phospholipids (PL). Dairy fat seems to act differently depending on the dairy product and the composition of macronutrients in the meal. Therefore, for a better understanding of the mechanisms behind the dairy protein and fat effect on MetS, we suggest that more human studies should be carried out to clarify the interactions of dairy protein and fat with macronutrients in the meal and other dairy components, such as micronutrients and microorganisms from fermented products. PMID:25396403

  4. Biochemical and metabolic mechanisms by which dietary whey protein may combat obesity and Type 2 diabetes.

    PubMed

    Jakubowicz, Daniela; Froy, Oren

    2013-01-01

    Consumption of milk and dairy products has been associated with reduced risk of metabolic disorders and cardiovascular disease. Milk contains two primary sources of protein, casein (80%) and whey (20%). Recently, the beneficial physiological effects of whey protein on the control of food intake and glucose metabolism have been reported. Studies have shown an insulinotropic and glucose-lowering properties of whey protein in healthy and Type 2 diabetes subjects. Whey protein seems to induce these effects via bioactive peptides and amino acids generated during its gastrointestinal digestion. These amino acids and peptides stimulate the release of several gut hormones, such as cholecystokinin, peptide YY and the incretins gastric inhibitory peptide and glucagon-like peptide 1 that potentiate insulin secretion from β-cells and are associated with regulation of food intake. The bioactive peptides generated from whey protein may also serve as endogenous inhibitors of dipeptidyl peptidase-4 (DPP-4) in the proximal gut, preventing incretin degradation. Indeed, recently, DPP-4 inhibitors were identified in whey protein hydrolysates. This review will focus on the emerging properties of whey protein and its potential clinical application for obesity and Type 2 diabetes.

  5. Innovative strategies to treat protein misfolding in inborn errors of metabolism: pharmacological chaperones and proteostasis regulators.

    PubMed

    Muntau, Ania C; Leandro, João; Staudigl, Michael; Mayer, Felix; Gersting, Søren W

    2014-07-01

    To attain functionality, proteins must fold into their three-dimensional native state. The intracellular balance between protein synthesis, folding, and degradation is constantly challenged by genetic or environmental stress factors. In the last ten years, protein misfolding induced by missense mutations was demonstrated to be the seminal molecular mechanism in a constantly growing number of inborn errors of metabolism. In these cases, loss of protein function results from early degradation of missense-induced misfolded proteins. Increasing knowledge on the proteostasis network and the protein quality control system with distinct mechanisms in different compartments of the cell paved the way for the development of new treatment strategies for conformational diseases using small molecules. These comprise proteostasis regulators that enhance the capacity of the proteostasis network and pharmacological chaperones that specifically bind and rescue misfolded proteins by conformational stabilization. They can be used either alone or in combination, the latter to exploit synergistic effects. Many of these small molecule compounds currently undergo preclinical and clinical pharmaceutical development and two have been approved: saproterin dihydrochloride for the treatment of phenylketonuria and tafamidis for the treatment of transthyretin-related hereditary amyloidosis. Different technologies are exploited for the discovery of new small molecule compounds that belong to the still young class of pharmaceutical products discussed here. These compounds may in the near future improve existing treatment strategies or even offer a first-time treatment to patients suffering from nowadays-untreatable inborn errors of metabolism. PMID:24687294

  6. Acrylamide administration alters protein phosphorylation and phospholipid metabolism in rat sciatic nerve

    SciTech Connect

    Berti-Mattera, L.N.; Eichberg, J.; Schrama, L.; LoPachin, R.M. )

    1990-05-01

    The effects of ACR on protein phosphorylation and phospholipid metabolism were assessed in rat sciatic nerve. After 5 days of ACR administration (50 mg/kg/day) an increase in the incorporation of 32P into phosphatidylinositol-4,5-bisphosphate, phosphatidylinositol-4-phosphate, and phosphatidylcholine was detected in proximal sciatic nerve segments. In contrast, no changes in phospholipid metabolism were observed in distal segments. After 9 days of ACR treatment when neurotoxicological symptoms were clearly apparent, a generalized increase in radiolabel uptake into phospholipids was noted exclusively in proximal nerve regions. ACR-induced increases in phospholipid metabolism were toxicologically specific since comparable administration of MBA (108 mg/kg/day X 5 or 9 days) produced only minor changes. ACR intoxication was also associated with a rise in sciatic nerve protein phosphorylation. After 9 days of ACR treatment, phosphorylation of beta-tubulin, P0, and several unidentified proteins (38 and 180 kDa) was increased in distal segments. In contrast, chronic administration of MBA caused increases in phosphorylation of beta-tubulin and the major myelin proteins of proximal nerve segments. In cell free homogenates prepared from sciatic nerves of treated and control rats, MBA caused an increase in phosphorylation of major myelin proteins similar to its effect in intact proximal nerve segments. The most striking effect observed in nerve homogenates of ACR-treated rats was a marked decrease in phosphorylation of an 80-kDa protein. Addition of ACR (1 mM) to homogenates of normal nerve had no effect on protein phosphorylation. Our results indicate that changes in the phosphorylation of phospholipids and proteins in sciatic nerve might be a component of the neurotoxic mechanism of ACR.

  7. Role of the AMP-activated protein kinase in regulating fatty acid metabolism during exercise.

    PubMed

    Steinberg, Gregory R

    2009-06-01

    During moderate-intensity exercise, fatty acids are the predominant substrate for working skeletal muscle. The release of fatty acids from adipose tissue stores, combined with the ability of skeletal muscle to actively fine tune the gradient between fatty acid and carbohydrate metabolism, depending on substrate availability and energetic demands, requires a coordinated system of metabolic control. Over the past decade, since the discovery that AMP-activated protein kinase (AMPK) was increased in accordance with exercise intensity, there has been significant interest in the proposed role of this ancient stress-sensing kinase as a critical integrative switch controlling metabolic responses during exercise. In this review, studies examining the role of AMPK as a regulator of fatty acid metabolism in both adipose tissue and skeletal muscle during exercise will be discussed. Exercise induces activation of AMPK in adipocytes and regulates triglyceride hydrolysis and esterfication through phosphorylation of hormone sensitive lipase (HSL) and glycerol-3-phosphate acyl-transferase, respectively. In skeletal muscle, exercise-induced activation of AMPK is associated with increases in fatty acid uptake, phosphorylation of HSL, and increased fatty acid oxidation, which is thought to occur via the acetyl-CoA carboxylase-malony-CoA-CPT-1 signalling axis. Despite the importance of AMPK in regulating fatty acid metabolism under resting conditions, recent evidence from transgenic models of AMPK deficiency suggest that alternative signalling pathways may also be important for the control of fatty acid metabolism during exercise.

  8. Nicotinamide N-methyltransferase regulates hepatic nutrient metabolism through Sirt1 protein stabilization

    PubMed Central

    Hong, Shangyu; Moreno-Navarrete, Jose M; Wei, Xiaojing; Kikukawa, Yusuke; Tzameli, Iphigenia; Prasad, Deepthi; Lee, Yoonjin; Asara, John M; Fernandez-Real, Jose Manuel; Maratos-Flier, Eleftheria; Pissios, Pavlos

    2015-01-01

    Nicotinamide N-methyltransferase (Nnmt) methylates nicotinamide, a form of vitamin B3, to produce N1-methylnicotinamide (MNAM). Nnmt is an emerging metabolic regulator in adipocytes but its role in the liver, a tissue with the strongest Nnmt expression, is not known. In spite of its overall high expression, here we find that hepatic expression of Nnmt is highly variable and correlates with multiple metabolic parameters in mice and in humans. Further, we find that suppression of hepatic Nnmt expression in vivo alters glucose and cholesterol metabolism and that the metabolic effects of Nnmt in the liver are mediated by its product MNAM. Supplementation of high fat diet with MNAM decreases serum and liver cholesterol and liver triglycerides levels in mice. Mechanistically, increasing Nnmt expression or MNAM levels stabilizes sirtuin 1 protein, an effect, which is required for their metabolic benefits. In summary, we describe a novel regulatory pathway for vitamin B3 that could provide a new opportunity for metabolic disease therapy. PMID:26168293

  9. The unfolded protein response mediates reversible tau phosphorylation induced by metabolic stress

    PubMed Central

    van der Harg, J M; Nölle, A; Zwart, R; Boerema, A S; van Haastert, E S; Strijkstra, A M; Hoozemans, J JM; Scheper, W

    2014-01-01

    The unfolded protein response (UPR) is activated in neurodegenerative tauopathies such as Alzheimer's disease (AD) in close connection with early stages of tau pathology. Metabolic disturbances are strongly associated with increased risk for AD and are a potent inducer of the UPR. Here, we demonstrate that metabolic stress induces the phosphorylation of endogenous tau via activation of the UPR. Strikingly, upon restoration of the metabolic homeostasis, not only the levels of the UPR markers pPERK, pIRE1α and BiP, but also tau phosphorylation are reversed both in cell models as well as in torpor, a physiological hypometabolic model in vivo. Intervention in the UPR using the global UPR inhibitor TUDCA or a specific small-molecule inhibitor of the PERK signaling pathway, inhibits the metabolic stress-induced phosphorylation of tau. These data support a role for UPR-mediated tau phosphorylation as part of an adaptive response to metabolic stress. Failure to restore the metabolic homeostasis will lead to prolonged UPR activation and tau phosphorylation, and may thus contribute to AD pathogenesis. We demonstrate that the UPR is functionally involved in the early stages of tau pathology. Our data indicate that targeting of the UPR may be employed for early intervention in tau-related neurodegenerative diseases. PMID:25165879

  10. Metabolic dynamics analysis by massive data integration: application to tsunami-affected field soils in Japan.

    PubMed

    Ogura, Tatsuki; Date, Yasuhiro; Tsuboi, Yuuri; Kikuchi, Jun

    2015-08-21

    A new metabolic dynamics analysis approach has been developed in which massive data sets from time-series of (1)H and (13)C NMR spectra are integrated in combination with microbial variability to characterize the biomass degradation process using field soil microbial communities. On the basis of correlation analyses that revealed relationships between various metabolites and bacteria, we efficiently monitored the metabolic dynamics of saccharides, amino acids, and organic acids, by assessing time-course changes in the microbial and metabolic profiles during biomass degradation. Specific bacteria were found to support specific steps of metabolic pathways in the degradation process of biomass to short chain fatty acids. We evaluated samples from agricultural and abandoned fields contaminated by the tsunami that followed the Great East earthquake in Japan. Metabolic dynamics and activities in the biomass degradation process differed considerably between soil from agricultural and abandoned fields. In particular, production levels of short chain fatty acids, such as acetate and propionate, which were considered to be produced by soil bacteria such as Sedimentibacter sp. and Coprococcus sp., were higher in the soil from agricultural fields than from abandoned fields. Our approach could characterize soil activity based on the metabolic dynamics of microbial communities in the biomass degradation process and should therefore be useful in future investigations of the environmental effects of natural disasters on soils.

  11. Metabolic dynamics analysis by massive data integration: application to tsunami-affected field soils in Japan.

    PubMed

    Ogura, Tatsuki; Date, Yasuhiro; Tsuboi, Yuuri; Kikuchi, Jun

    2015-08-21

    A new metabolic dynamics analysis approach has been developed in which massive data sets from time-series of (1)H and (13)C NMR spectra are integrated in combination with microbial variability to characterize the biomass degradation process using field soil microbial communities. On the basis of correlation analyses that revealed relationships between various metabolites and bacteria, we efficiently monitored the metabolic dynamics of saccharides, amino acids, and organic acids, by assessing time-course changes in the microbial and metabolic profiles during biomass degradation. Specific bacteria were found to support specific steps of metabolic pathways in the degradation process of biomass to short chain fatty acids. We evaluated samples from agricultural and abandoned fields contaminated by the tsunami that followed the Great East earthquake in Japan. Metabolic dynamics and activities in the biomass degradation process differed considerably between soil from agricultural and abandoned fields. In particular, production levels of short chain fatty acids, such as acetate and propionate, which were considered to be produced by soil bacteria such as Sedimentibacter sp. and Coprococcus sp., were higher in the soil from agricultural fields than from abandoned fields. Our approach could characterize soil activity based on the metabolic dynamics of microbial communities in the biomass degradation process and should therefore be useful in future investigations of the environmental effects of natural disasters on soils. PMID:25997449

  12. Marked over expression of uncoupling protein-2 in beta cells exerts minor effects on mitochondrial metabolism

    SciTech Connect

    Hals, Ingrid K.; Ogata, Hirotaka; Pettersen, Elin; Ma, Zuheng; Bjoerklund, Anneli; Skorpen, Frank; Egeberg, Kjartan Wollo; Grill, Valdemar

    2012-06-29

    Highlights: Black-Right-Pointing-Pointer The impact of UCP-2 over expression on mitochondrial function is controversial. Black-Right-Pointing-Pointer We tested mitochondrial functions at defined levels of overexpression. Black-Right-Pointing-Pointer We find minor increases of fatty acid oxidation and uncoupling. Black-Right-Pointing-Pointer Effects were seen only at high level (fourfold) of over expression. Black-Right-Pointing-Pointer Hence it is doubtful whether these effects are of importance in diabetes. -- Abstract: Evidence is conflicting as to the impact of elevated levels of uncoupling protein-2 (UCP-2) on insulin-producing beta cells. Here we investigated effects of a fourfold induction of UCP-2 protein primarily on mitochondrial parameters and tested for replication of positive findings at a lower level of induction. We transfected INS-1 cells to obtain a tet-on inducible cell line. A 48 h exposure to 1 {mu}g/ml of doxycycline (dox) induced UCP-2 fourfold (424 {+-} 113%, mean {+-} SEM) and 0.1 {mu}g/ml twofold (178 {+-} 29%, n = 3). Fourfold induced cells displayed normal viability (MTT, apoptosis), normal cellular insulin contents and, glucose-induced insulin secretion (+27 {+-} 11%) as well as D-[U-{sup 14}C]-glucose oxidation (+5 {+-} 9% at 11 mM glucose). Oxidation of [1-{sup 14}C]-oleate was increased from 4088 to 5797 fmol/{mu}g prot/2 h at 3.3 mM glucose, p < 0.03. Oxidation of L-[{sup 14}C(U)]-glutamine was unaffected. Induction of UCP-2 did not significantly affect measures of mitochondrial membrane potential (Rhodamine 123) or mitochondrial mass (Mitotracker Green) and did not affect ATP levels. Oligomycin-inhibited oxygen consumption (a measure of mitochondrial uncoupling) was marginally increased, the effect being significant in comparison with dox-only treated cells, p < 0.05. Oxygen radicals, assessed by dichlorofluorescin diacetate, were decreased by 30%, p < 0.025. Testing for the lower level of UCP-2 induction did not reproduce any of the

  13. Macroautophagy and Cell Responses Related to Mitochondrial Dysfunction, Lipid Metabolism and Unconventional Secretion of Proteins

    PubMed Central

    Demine, Stéphane; Michel, Sébastien; Vannuvel, Kayleen; Wanet, Anaïs; Renard, Patricia; Arnould, Thierry

    2012-01-01

    Macroautophagy has important physiological roles and its cytoprotective or detrimental function is compromised in various diseases such as many cancers and metabolic diseases. However, the importance of autophagy for cell responses has also been demonstrated in many other physiological and pathological situations. In this review, we discuss some of the recently discovered mechanisms involved in specific and unspecific autophagy related to mitochondrial dysfunction and organelle degradation, lipid metabolism and lipophagy as well as recent findings and evidence that link autophagy to unconventional protein secretion. PMID:24710422

  14. Protein sorting gone wrong--VPS10P domain receptors in cardiovascular and metabolic diseases.

    PubMed

    Schmidt, Vanessa; Willnow, Thomas E

    2016-02-01

    VPS10P domain receptors are a unique class of sorting receptors that direct intracellular transport of target proteins in neurons and that play central roles in neurodegenerative processes. Surprisingly, genome-wide association studies now implicate the very same receptors in cardiovascular and metabolic disturbances. In this review, we discuss current findings that uncovered some of the molecular mechanisms whereby sorting receptors, such as SORLA, sortilin, and SORCS1 control homeostasis in cardiovascular and metabolic tissues, and how they promote hypercholesterolemia, atherosclerosis, obesity, and diabetes, when being altered. PMID:26724530

  15. Expression of metabolism-related proteins in triple-negative breast cancer

    PubMed Central

    Kim, Min-Ju; Kim, Do-Hee; Jung, Woo-Hee; Koo, Ja-Seung

    2014-01-01

    To investigate the dominant metabolic type of triple-negative breast cancer (TNBC) and evaluate its clinical implication through analysis of protein expression related to glycolysis, glutaminolysis, and mitochondrial oxidative phosphorylation. Tissue samples from 129 patients with TNBC who underwent mastectomy due to invasive breast cancer from 2000 to 2005 were prepared for tissue microarray. By immunohistochemical staining of the tissue microarrays, the markers of glycolysis-related proteins (Glut-1, CAIX, MCT4), glutaminolysis-related proteins (GLS1, GDH, ASCT2), and mitochondrial enzymes (ATP synthase, SDHA and SDHB) were analyzed. Based on the results, the metabolic phenotypes were defined based on positivity for more than two of three markers for each phenotype as follows: glycolysis type (Glut-1, CAIX and MCT4), glutaminolysis type (GLS1, GDH and ASCT2) and mitochondrial type (ATP synthase, SDHA and SDHB). The percentages of samples with metabolic phenotypes of tumor and stroma of TNBC were as follows: for tumor, mitochondrial type (85.3%) > glutaminolysis type (67.4%) > glycolysis type (63.0%); and for stroma, glutaminolysis type (37.2%) > glycolysis type (16.3%) > mitochondrial type (14.0%). The most common metabolic phenotype of TNBC was glycolysis type for basal-like type and non-glycolysis type for non-basal-like type (p=0.047). The correlation between glutaminolysis and mitochondrial type was statistically significant in both tumor and stroma (p<0.001). In conclusion, tumor cells of TNBC express glycolysis and mitochondrial metabolism-related proteins. Glycolysis type is the most common phenotype of basal-like type, and reversely, non-glycolysis type is the most common phenotype of non basal-like type. PMID:24427351

  16. Concentration dependent effects of tobacco particulates from different types of cigarettes on expression of drug metabolizing proteins, and benzo(a)pyrene metabolism in primary normal human oral epithelial cells

    PubMed Central

    Sacks, Peter G.; Zhao, Zhong-Lin; Kosinska, Wieslawa; Fleisher, Kenneth E.; Gordon, Terry; Guttenplan, Joseph B.

    2011-01-01

    The ability of tobacco smoke (TS) to modulate phase I and II enzymes and affect metabolism of tobacco carcinogens is likely an important factor in its carcinogenicity. For the first time several types of TS particulates (TSP) were compared in different primary cultured human oral epithelial cells (NOE) for their abilities to affect metabolism of the tobacco carcinogen, (BaP) to genotoxic products, and expression of drug metabolizing enzymes. TSP from, reference filtered (2RF4), mentholated (MS), reference unfiltered, (IR3), ultra low tar (UL), and cigarettes that primarily heat tobacco (ECL) were tested. Cells pretreated with TSP concentrations of 0.2 – 10 µg/ml generally showed increased rates of BaP metabolism; those treated with TSP concentrations above 10 µg/ml showed decreased rates. Effects of TSPs were similar when expressed on a weight basis. Weights of TSP/cigarette varied in the order: MS ≈ IR3 > 2RF4 > ECL > UL. All TSPs induced the phase I proteins, cytochrome P450 1A1 (CYP1A1) and 1B1 (CYP1B1), phase II proteins, NAD(P)H dehydrogenase quinone 1 (NQO1), and microsomal glutathione S-transferase 1 (MGST1), and additionally, hydroxysteroid (17-beta) dehydrogenase 2 (HSD17B2), as assessed by qRT-PCR. The pattern of gene induction at probable physiological levels favored activation over detoxification. PMID:21722697

  17. Bisphenol A affects early bovine embryo development and metabolism that is negated by an oestrogen receptor inhibitor

    PubMed Central

    Choi, Bom-Ie; Harvey, Alexandra J.; Green, Mark P.

    2016-01-01

    Increasing evidence supports an association between exposure to endocrine disruptors, such as the xenoestrogen bisphenol A (BPA), a commonly used plasticiser, and the developmental programming of offspring health. To date however animal studies to investigate a direct causal have mainly focussed on supra-environmental BPA concentrations, without investigating the effect on the early embryo. In this study we investigated the effect of acute BPA exposure (days 3.5 to 7.5 post-fertilisation) at environmentally relevant concentrations (1 and 10 ng/mL) on in vitro bovine embryo development, quality and metabolism. We then examined whether culturing embryos in the presence of the oestrogen receptor inhibitor fulvestrant could negate effects of BPA and 17β-oestradiol (E2). Exposure to BPA or E2 (10 ng/mL) decreased blastocyst rate and the percentage of transferrable quality embryos, without affecting cell number, lineage allocation or metabolic gene expression compared to untreated embryos. Notably, blastocysts exposed to BPA and E2 (10 ng/mL) displayed an increase in glucose consumption. The presence of fulvestrant however negated the adverse developmental and metabolic effects, suggesting BPA elicits its effects via oestrogen-mediated pathways. This study demonstrates that even acute exposure to an environmentally relevant BPA concentration can affect early embryo development and metabolism. These may have long-term health consequences on an individual. PMID:27384909

  18. Bisphenol A affects early bovine embryo development and metabolism that is negated by an oestrogen receptor inhibitor.

    PubMed

    Choi, Bom-Ie; Harvey, Alexandra J; Green, Mark P

    2016-01-01

    Increasing evidence supports an association between exposure to endocrine disruptors, such as the xenoestrogen bisphenol A (BPA), a commonly used plasticiser, and the developmental programming of offspring health. To date however animal studies to investigate a direct causal have mainly focussed on supra-environmental BPA concentrations, without investigating the effect on the early embryo. In this study we investigated the effect of acute BPA exposure (days 3.5 to 7.5 post-fertilisation) at environmentally relevant concentrations (1 and 10 ng/mL) on in vitro bovine embryo development, quality and metabolism. We then examined whether culturing embryos in the presence of the oestrogen receptor inhibitor fulvestrant could negate effects of BPA and 17β-oestradiol (E2). Exposure to BPA or E2 (10 ng/mL) decreased blastocyst rate and the percentage of transferrable quality embryos, without affecting cell number, lineage allocation or metabolic gene expression compared to untreated embryos. Notably, blastocysts exposed to BPA and E2 (10 ng/mL) displayed an increase in glucose consumption. The presence of fulvestrant however negated the adverse developmental and metabolic effects, suggesting BPA elicits its effects via oestrogen-mediated pathways. This study demonstrates that even acute exposure to an environmentally relevant BPA concentration can affect early embryo development and metabolism. These may have long-term health consequences on an individual. PMID:27384909

  19. Severe dietary lysine restriction affects growth and body composition and hepatic gene expression for nitrogen metabolism in growing rats.

    PubMed

    Kim, J; Lee, K S; Kwon, D-H; Bong, J J; Jeong, J Y; Nam, Y S; Lee, M S; Liu, X; Baik, M

    2014-02-01

    Dietary lysine restriction may differentially affect body growth and lipid and nitrogen metabolism, depending on the degree of lysine restriction. This study was conducted to examine the effect of dietary lysine restriction on growth and lipid and nitrogen metabolism with two different degree of lysine restriction. Isocaloric amino acid-defined diets containing 1.4% lysine (adequate), 0.70% lysine (50% moderate lysine restriction) and 0.35% lysine (75% severe lysine restriction) were fed from the age of 52 to 77 days for 25 days in male Sprague-Dawley rats. The 75% severe lysine restriction increased (p < 0.05) food intake, but retarded (p < 0.05) growth, increased (p < 0.05) liver and muscle lipid contents and abdominal fat accumulation, increased (p < 0.05) blood urea nitrogen levels and mRNA levels of the serine-synthesizing 3-phosphoglycerate dehydrogenase gene, but decreased (p < 0.05) urea cycle arginase gene mRNA levels. In contrast, the 50% lysine restriction did not significantly (p > 0.05) affect body growth and lipid and nitrogen metabolism. Our results demonstrate that severe 75% lysine restriction has detrimental effects on body growth and deregulate lipid and nitrogen metabolism. PMID:23441935

  20. Growth, nutrient retention, and metabolic response in low birth weight infants fed varying intakes of protein and energy.

    PubMed

    Kashyap, S; Schulze, K F; Forsyth, M; Zucker, C; Dell, R B; Ramakrishnan, R; Heird, W C

    1988-10-01

    Growth, nutrient retention, and metabolic response were determined in low birth weight (LBW) infants fed daily protein and energy intakes, respectively, of 2.8 gm/kg and 119 kcal/kg (group 1), 3.8 gm/kg and 120 kcal/kg (group 2), and 3.9 gm/kg and 142 kcal/kg (group 3). The mean rates of both weight gain and nitrogen retention in group 1 were somewhat greater than intrauterine rates; plasma concentrations of transthyretin and albumin also were acceptable. Thus the lower protein intake appeared to be adequate. On the other hand, the rates of weight gain and nitrogen retention in groups 2 and 3 were greater than those in group 1, supporting the efficacy of the higher protein intake with respect to growth. However, blood urea nitrogen and plasma amino acid concentrations also were higher in groups 2 and 3; both were higher in group 2 than in group 3, reflecting the positive effect of the higher energy intake on protein utilization. This observation, combined with data from an earlier study, indicates that protein intakes in excess of 3 gm/100 kcal will not be utilized completely. Energy expenditure in group 3 was greater than in group 1 but not group 2, raising the possibility that protein intakes not utilized completely contribute to diet-induced thermogenesis. The higher energy intake in group 3 vs group 2 did not affect rate of weight gain significantly, but energy storage in group 3, and hence fat accretion, was greater than that of other groups. In all groups the ratio of protein accretion to fat accretion reflected dietary proportions of protein and energy.

  1. Putative drug and vaccine target protein identification using comparative genomic analysis of KEGG annotated metabolic pathways of Mycoplasma hyopneumoniae.

    PubMed

    Damte, Dereje; Suh, Joo-Won; Lee, Seung-Jin; Yohannes, Sileshi Belew; Hossain, Md Akil; Park, Seung-Chun

    2013-07-01

    In the present study, a computational comparative and subtractive genomic/proteomic analysis aimed at the identification of putative therapeutic target and vaccine candidate proteins from Kyoto Encyclopedia of Genes and Genomes (KEGG) annotated metabolic pathways of Mycoplasma hyopneumoniae was performed for drug design and vaccine production pipelines against M.hyopneumoniae. The employed comparative genomic and metabolic pathway analysis with a predefined computational systemic workflow extracted a total of 41 annotated metabolic pathways from KEGG among which five were unique to M. hyopneumoniae. A total of 234 proteins were identified to be involved in these metabolic pathways. Although 125 non homologous and predicted essential proteins were found from the total that could serve as potential drug targets and vaccine candidates, additional prioritizing parameters characterize 21 proteins as vaccine candidate while druggability of each of the identified proteins evaluated by the DrugBank database prioritized 42 proteins suitable for drug targets.

  2. Effect of branched chain amino acid infusions on body protein metabolism in cirrhosis of liver.

    PubMed Central

    Wright, P D; Holdsworth, J D; Dionigi, P; Clague, M B; James, O F

    1986-01-01

    Thirty seven patients with established cirrhosis of the liver were subjected to measurement of body protein metabolism using L-(1-14C) labelled leucine as a tracer. The effects of disease severity and those of solutions containing 0%, 16%, 35%, 53%, and 100% branched chain amino acids were evaluated. Significant increases in protein synthesis were noted with solutions containing 35%, 53%, and 100% branched chain amino acids, but in patients receiving 100% branched chain amino acids without additional essential amino acid supplement the increase in synthesis was matched by a significant increase in protein breakdown. Protein balance was thus improved only in patients receiving 35% and 53% branched chain amino acids. It was concluded that the high increase in protein breakdown in patients receiving 100% branched chain amino acids was undesirable, and such a solution should not be recommended for clinical use. PMID:3539714

  3. Protein metabolism in growing pigs fed corn or cassava peel based diets containing graded protein levels.

    PubMed

    Tewe, O O

    1985-05-01

    Sixty-four Large White cross Landrace weanling pigs were randomly allotted to eight treatments in a two by four factorial arrangement. The two dietary variables were cassava peel (0 and 40 per cent) and crude protein (20, 15, 10 and 5 per cent). Total serum protein concentration was significantly (P less than 0.01) reduced by protein deficiency and by its interaction with cassava peel. The multiple coefficient of determination (R2) showed that protein intake was the primary factor determining changes in serum protein. R2 values for cyanide intake (independent variable) on serum protein (dependent variable) increased from day 30 to 90 of the trial. Serum urea was increased on the 5 per cent protein diets on days 60 and 90 of the trial. The R2 values for cyanide and protein intake on serum urea concentration increased from day 30 to day 90 of the trial. Serum creatinine increased (P less than 0.05) on the 5 per cent protein diet on day 90 of the trial. The R2 value for the effects of protein intake on serum creatinine was higher than for cyanide intake on days 30 and 90. The results confirm the progressive and pronounced effects of long term cyanide intake on serum nitrogenous metabolites in pigs consuming between 110 and 120 ppm hydrocyanic acid, especially in diets containing 10 per cent or less protein. PMID:2989987

  4. Intrinsically Disordered Segments Affect Protein Half-Life in the Cell and during Evolution

    PubMed Central

    van der Lee, Robin; Lang, Benjamin; Kruse, Kai; Gsponer, Jörg; Sánchez de Groot, Natalia; Huynen, Martijn A.; Matouschek, Andreas; Fuxreiter, Monika; Babu, M. Madan

    2014-01-01

    Summary Precise control of protein turnover is essential for cellular homeostasis. The ubiquitin-proteasome system is well established as a major regulator of protein degradation, but an understanding of how inherent structural features influence the lifetimes of proteins is lacking. We report that yeast, mouse, and human proteins with terminal or internal intrinsically disordered segments have significantly shorter half-lives than proteins without these features. The lengths of the disordered segments that affect protein half-life are compatible with the structure of the proteasome. Divergence in terminal and internal disordered segments in yeast proteins originating from gene duplication leads to significantly altered half-life. Many paralogs that are affected by such changes participate in signaling, where altered protein half-life will directly impact cellular processes and function. Thus, natural variation in the length and position of disordered segments may affect protein half-life and could serve as an underappreciated source of genetic variation with important phenotypic consequences. PMID:25220455

  5. Acclimation temperature affects the metabolic response of amphibian skeletal muscle to insulin.

    PubMed

    Petersen, Ann M; Gleeson, Todd T

    2011-09-01

    Frog skeletal muscle mainly utilizes the substrates glucose and lactate for energy metabolism. The goal of this study was to determine the effect of insulin on the uptake and metabolic fate of lactate and glucose at rest in skeletal muscle of the American bullfrog, Lithobates catesbeiana, under varying temperature regimens. We hypothesize that lactate and glucose metabolic pathways will respond differently to the presence of insulin in cold versus warm acclimated frog tissues, suggesting an interaction between temperature and metabolism under varying environmental conditions. We employed radiolabeled tracer techniques to measure in vitro uptake, oxidation, and incorporation of glucose and lactate into glycogen by isolated muscles from bullfrogs acclimated to 5 °C (cold) or 25 °C (warm). Isolated bundles from Sartorius muscles were incubated at 5 °C, 15 °C, or 25 °C, and in the presence and absence of 0.05 IU/mL bovine insulin. Insulin treatment in the warm acclimated and incubated frogs resulted in an increase in glucose incorporation into glycogen, and an increase in intracellular [glucose] of 0.5 μmol/g (P<0.05). Under the same conditions lactate incorporation into glycogen was reduced (P<0.05) in insulin-treated muscle. When compared to the warm treatment group, cold acclimation and incubation resulted in increased rates of glucose oxidation and glycogen synthesis, and a reduction in free intracellular glucose levels (P<0.05). When muscles from either acclimation group were incubated at an intermediate temperature of 15 °C, insulin's effect on substrate metabolism was attenuated or even reversed. Therefore, a significant interaction between insulin and acclimation condition in controlling skeletal muscle metabolism appears to exist. Our findings further suggest that one of insulin's actions in frog muscle is to increase glucose incorporation into glycogen, and to reduce reliance on lactate as the primary metabolic fuel. PMID:21605693

  6. Metabolic and Genomic Response to Dietary Isocaloric Protein Restriction in the Rat*

    PubMed Central

    Kalhan, Satish C.; Uppal, Sonal O.; Moorman, Jillian L.; Bennett, Carole; Gruca, Lourdes L.; Parimi, Prabhu S.; Dasarathy, Srinivasan; Serre, David; Hanson, Richard W.

    2011-01-01

    We have examined hepatic, genomic, and metabolic responses to dietary protein restriction in the non-pregnant Sprague-Dawley rat. Animals were pair-fed either a 6 or 24% casein-based diet for 7–10 days. At the end of the dietary period, a microarray analysis of the liver was performed, followed by validation of the genes of interest. The rates of appearance of phenylalanine, methionine, serine, and glucose and the contribution of pyruvate to serine and glucose were quantified using tracer methods. Plasma and tissue amino acid levels, enzyme activities, and metabolic intermediates were measured. Protein restriction resulted in significant differential expression of a number of genes involved in cell cycle, cell differentiation, transport, transcription, and metabolic processes. RT-PCR showed that the expression of genes involved in serine biosynthesis and fatty acid oxidation was higher, and those involved in fatty acid synthesis and urea synthesis were lower in the liver of protein-restricted animals. Free serine and glycine levels were higher and taurine levels lower in all tissues examined. Tracer isotope studies showed an ∼50% increase in serine de novo synthesis. Pyruvate was the primary (∼90%) source of serine in both groups. Transmethylation of methionine was significantly higher in the protein-restricted group. This was associated with a higher S-adenosylmethionine/S-adenosylhomocysteine ratio and lower cystathione β-synthase and cystathionine γ-lyase activity. Dietary isocaloric protein restriction results in profound changes in hepatic one-carbon metabolism within a short period. These may be related to high methylation demands placed on the organism and caused by possible changes in cellular osmolarity as a result of the efflux of the intracellular taurine. PMID:21147771

  7. Investigation into the role of catabolite control protein A in the metabolic regulation of Streptococcus suis serotype 2 using gene expression profile analysis

    PubMed Central

    LANG, XULONG; WAN, ZHONGHAI; PAN, YING; WANG, XIURAN; WANG, XIAOXU; BU, ZHAOYANG; QIAN, JING; ZENG, HUAZONG; WANG, XINGLONG

    2015-01-01

    Catabolite control protein A (CcpA) serves a key function in the catabolism of Streptococcus suis serotype 2 (S. suis 2) by affecting the biological function and metabolic regulatory mechanisms of this bacterium. The aim of the present study was to identify variations in CcpA expression in S. suis 2 using gene expression profile analysis. Using sequencing and functional analysis, CcpA was demonstrated to play a regulatory role in the expression and regulation of virulence genes, carbon metabolism and immunoregulation in S. suis 2. Gene Ontology and Kyto Encyclopedia of Genes and Genomes analyses indicated that CcpA in S. suis 2 is involved in the regulation of multiple metabolic processes. Furthermore, combined analysis of the transcriptome and metabolite data suggested that metabolites varied due to the modulation of gene expression levels under the influence of CcpA regulation. In addition, metabolic network analysis indicated that CcpA impacted carbon metabolism to a certain extent. Therefore, the present study has provided a more comprehensive analysis of the role of CcpA in the metabolic regulation of S. suis 2, which may facilitate future investigation into this mechanism. Furthermore, the results of the present study provide a foundation for further research into the regulatory function of CcpA and associated metabolic pathways in S. suis 2. PMID:26170923

  8. Protein source and choice of anticoagulant decisively affect nanoparticle protein corona and cellular uptake

    NASA Astrophysics Data System (ADS)

    Schöttler, S.; Klein, Katja; Landfester, K.; Mailänder, V.

    2016-03-01

    Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance of the choice of protein source used for in vitro protein corona analysis is concisely investigated. Major and decisive differences in cellular uptake of a polystyrene nanoparticle incubated in fetal bovine serum, human serum, human citrate and heparin plasma are reported. Furthermore, the protein compositions are determined for coronas formed in the respective incubation media. A strong influence of heparin, which is used as an anticoagulant for plasma generation, on cell interaction is demonstrated. While heparin enhances the uptake into macrophages, it prevents internalization into HeLa cells. Taken together we can give the recommendation that human plasma anticoagulated with citrate seems to give the most relevant results for in vitro studies of nanoparticle uptake.Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance

  9. Sulfate resupply accentuates protein synthesis in coordination with nitrogen metabolism in sulfur deprived Brassica napus.

    PubMed

    Zhang, Qian; Lee, Bok-Rye; Park, Sang-Hyun; Zaman, Rashed; Avice, Jean-Christophe; Ourry, Alain; Kim, Tae-Hwan

    2015-02-01

    To investigate the regulatory interactions between S assimilation and N metabolism in Brassica napus, de novo synthesis of amino acids and proteins was quantified by (15)N and (34)S tracing, and the responses of transporter genes, assimilatory enzymes and metabolites pool involving in nitrate and sulfate metabolism were assessed under continuous sulfur supply, sulfur deprivation and sulfate resupply after 3 days of sulfur (S) deprivation. S-deprived plants were characterized by a strong induction of sulfate transporter genes, ATP sulfurylase (ATPS) and adenosine 5'-phosphosulfate reductase (APR), and by a repressed activity of nitrate reductase (NR) and glutamine synthetase (GS). Sulfate resupply to the S-deprived plants strongly increased cysteine, amino acids and proteins concentration. The increase in sulfate and cysteine concentration caused by sulfate resupply was not matched with the expression of sulfate transporters and the activity of ATPS and APR which were rapidly decreased by sulfate resupply. A strong induction of O-acetylserine(thiol)lyase (OASTL), NR and GS upon sulfate resupply was accompanied with the increase in cysteine, amino acids and proteins pool. Sulfate resupply resulted in a strong increase in de novo synthesis of amino acids and proteins, as evidenced by the increases in N and S incorporation into amino acids (1.8- and 2.4-fold increase) and proteins (2.2-and 6.3-fold increase) when compared to S-deprived plants. The results thus indicate that sulfate resupply followed by S-deprivation accelerates nitrate assimilation for protein synthesis.

  10. Quantitative H2S-mediated protein sulfhydration reveals metabolic reprogramming during the integrated stress response

    PubMed Central

    Gao, Xing-Huang; Krokowski, Dawid; Guan, Bo-Jhih; Bederman, Ilya; Majumder, Mithu; Parisien, Marc; Diatchenko, Luda; Kabil, Omer; Willard, Belinda; Banerjee, Ruma; Wang, Benlian; Bebek, Gurkan; Evans, Charles R.; Fox, Paul L.; Gerson, Stanton L.; Hoppel, Charles L.; Liu, Ming; Arvan, Peter; Hatzoglou, Maria

    2015-01-01

    The sulfhydration of cysteine residues in proteins is an important mechanism involved in diverse biological processes. We have developed a proteomics approach to quantitatively profile the changes of sulfhydrated cysteines in biological systems. Bioinformatics analysis revealed that sulfhydrated cysteines are part of a wide range of biological functions. In pancreatic β cells exposed to endoplasmic reticulum (ER) stress, elevated H2S promotes the sulfhydration of enzymes in energy metabolism and stimulates glycolytic flux. We propose that transcriptional and translational reprogramming by the integrated stress response (ISR) in pancreatic β cells is coupled to metabolic alternations triggered by sulfhydration of key enzymes in intermediary metabolism. DOI: http://dx.doi.org/10.7554/eLife.10067.001 PMID:26595448

  11. Efficient recovery of recombinant proteins from cereal endosperm is affected by interaction with endogenous storage proteins.

    PubMed

    Peters, Jenny; Sabalza, Maite; Ramessar, Koreen; Christou, Paul; Capell, Teresa; Stöger, Eva; Arcalís, Elsa

    2013-10-01

    Cereal seeds are versatile platforms for the production of recombinant proteins because they provide a stable environment for protein accumulation. Endogenous seed storage proteins, however, include several prolamin-type polypeptides that aggregate and crosslink via intermolecular disulfide bridges, which could potentially interact with multimeric recombinant proteins such as antibodies, which assemble in the same manner. We investigated this possibility by sequentially extracting a human antibody expressed in maize endosperm, followed by precipitation in vitro with zein. We provide evidence that a significant proportion of the antibody pool interacts with zein and therefore cannot be extracted using non-reducing buffers. Immunolocalization experiments demonstrated that antibodies targeted for secretion were instead retained within zein bodies because of such covalent interactions. Our findings suggest that the production of soluble recombinant antibodies in maize could be enhanced by eliminating or minimizing interactions with endogenous storage proteins.

  12. L-Alanylglutamine inhibits signaling proteins that activate protein degradation, but does not affect proteins that activate protein synthesis after an acute resistance exercise.

    PubMed

    Wang, Wanyi; Choi, Ran Hee; Solares, Geoffrey J; Tseng, Hung-Min; Ding, Zhenping; Kim, Kyoungrae; Ivy, John L

    2015-07-01

    Sustamine™ (SUS) is a dipeptide composed of alanine and glutamine (AlaGln). Glutamine has been suggested to increase muscle protein accretion; however, the underlying molecular mechanisms of glutamine on muscle protein metabolism following resistance exercise have not been fully addressed. In the present study, 2-month-old rats climbed a ladder 10 times with a weight equal to 75 % of their body mass attached at the tail. Rats were then orally administered one of four solutions: placebo (PLA-glycine = 0.52 g/kg), whey protein (WP = 0.4 g/kg), low dose of SUS (LSUS = 0.1 g/kg), or high dose of SUS (HSUS = 0.5 g/kg). An additional group of sedentary (SED) rats was intubated with glycine (0.52 g/kg) at the same time as the ladder-climbing rats. Blood samples were collected immediately after exercise and at either 20 or 40 min after recovery. The flexor hallucis longus (FHL), a muscle used for climbing, was excised at 20 or 40 min post exercise and analyzed for proteins regulating protein synthesis and degradation. All supplements elevated the phosphorylation of FOXO3A above SED at 20 min post exercise, but only the SUS supplements significantly reduced the phosphorylation of AMPK and NF-kB p65. SUS supplements had no effect on mTOR signaling, but WP supplementation yielded a greater phosphorylation of mTOR, p70S6k, and rpS6 compared with PLA at 20 min post exercise. However, by 40 min post exercise, phosphorylation of mTOR and rpS6 in PLA had risen to levels not different than WP. These results suggest that SUS blocks the activation of intracellular signals for MPB, whereas WP accelerates mRNA translation.

  13. Immunocytochemical staining for glial fibrillary acidic protein and the metabolism of cytoskeletal proteins in experimental allergic encephalomyelitis.

    PubMed

    Smith, M E; Somera, F P; Eng, L F

    1983-04-01

    Spinal cord sections from Lewis rats with acute experimental allergic encephalomyelitis (EAE) showed greatly increased staining of astrocytes when stained immunocytochemically for glial fibrillary acidic protein (GFAP). Fibrous processes in white matter were heavily stained early in the course of the disease when paralysis was first evident (10-12 days after injection of guinea pig spinal cord myelin), then protoplasmic astrocytes were stained in the gray matter and became more heavily stained at 20 days post-injection. The stained astrocytes were evenly distributed throughout the tissue, and did not correspond to the sites of the lesions. Spinal cord slices of control and EAE rats were incubated with [3H]amino acids, then cytoskeletal proteins were prepared in an enriched fraction, separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and the protein bands counted for radioactivity. In the EAE rat all cytoskeletal proteins, including the neurofilaments, vimentin, microtubules, GFAP and actin, showed increased uptake of radioactive amino acids. Immunoprecipitation of GFAP with specific antiserum showed increased radioactivity in the complex beginning at day 10 when cellular infiltration was beginning in the EAE animals. As the disease became acute, the radioactivity in the immunoprecipitated GFAP increased, in some cases to very high levels, then by day 18 when recovery was underway, the radioactivity had fallen to normal levels. Possible agents causing metabolic activation of protein synthesis in EAE animals include stimulating substances elaborated by infiltrating lymphoid cells, and the generalized edema accompanying the demyelinative condition. The activation of GFAP protein staining and metabolism in EAE might serve as a model for the activated growth of astrocyte processes which cause the severe gliosis seen in multiple sclerosis.

  14. Protein Kinase A Subunit Balance Regulates Lipid Metabolism in Caenorhabditis elegans and Mammalian Adipocytes.

    PubMed

    Lee, Jung Hyun; Han, Ji Seul; Kong, Jinuk; Ji, Yul; Lv, Xuchao; Lee, Junho; Li, Peng; Kim, Jae Bum

    2016-09-23

    Protein kinase A (PKA) is a cyclic AMP (cAMP)-dependent protein kinase composed of catalytic and regulatory subunits and involved in various physiological phenomena, including lipid metabolism. Here we demonstrated that the stoichiometric balance between catalytic and regulatory subunits is crucial for maintaining basal PKA activity and lipid homeostasis. To uncover the potential roles of each PKA subunit, Caenorhabditis elegans was used to investigate the effects of PKA subunit deficiency. In worms, suppression of PKA via RNAi resulted in severe phenotypes, including shortened life span, decreased egg laying, reduced locomotion, and altered lipid distribution. Similarly, in mammalian adipocytes, suppression of PKA regulatory subunits RIα and RIIβ via siRNAs potently stimulated PKA activity, leading to potentiated lipolysis without increasing cAMP levels. Nevertheless, insulin exerted anti-lipolytic effects and restored lipid droplet integrity by antagonizing PKA action. Together, these data implicate the importance of subunit stoichiometry as another regulatory mechanism of PKA activity and lipid metabolism.

  15. Protein Kinase A Subunit Balance Regulates Lipid Metabolism in Caenorhabditis elegans and Mammalian Adipocytes.

    PubMed

    Lee, Jung Hyun; Han, Ji Seul; Kong, Jinuk; Ji, Yul; Lv, Xuchao; Lee, Junho; Li, Peng; Kim, Jae Bum

    2016-09-23

    Protein kinase A (PKA) is a cyclic AMP (cAMP)-dependent protein kinase composed of catalytic and regulatory subunits and involved in various physiological phenomena, including lipid metabolism. Here we demonstrated that the stoichiometric balance between catalytic and regulatory subunits is crucial for maintaining basal PKA activity and lipid homeostasis. To uncover the potential roles of each PKA subunit, Caenorhabditis elegans was used to investigate the effects of PKA subunit deficiency. In worms, suppression of PKA via RNAi resulted in severe phenotypes, including shortened life span, decreased egg laying, reduced locomotion, and altered lipid distribution. Similarly, in mammalian adipocytes, suppression of PKA regulatory subunits RIα and RIIβ via siRNAs potently stimulated PKA activity, leading to potentiated lipolysis without increasing cAMP levels. Nevertheless, insulin exerted anti-lipolytic effects and restored lipid droplet integrity by antagonizing PKA action. Together, these data implicate the importance of subunit stoichiometry as another regulatory mechanism of PKA activity and lipid metabolism. PMID:27496951

  16. Aberrant protein acylation is a common observation in inborn errors of acyl-CoA metabolism.

    PubMed

    Pougovkina, Olga; Te Brinke, Heleen; Wanders, Ronald J A; Houten, Sander M; de Boer, Vincent C J

    2014-09-01

    Inherited disorders of acyl-CoA metabolism, such as defects in amino acid metabolism and fatty acid oxidation can present with severe clinical symptoms either neonatally or later in life, but the pathophysiological mechanisms are often incompletely understood. We now report the discovery of a novel biochemical mechanism that could contribute to the pathophysiology of these disorders. We identified increased protein lysine butyrylation in short-chain acyl-CoA dehydrogenase (SCAD) deficient mice as a result of the accumulation of butyryl-CoA. Similarly, in SCAD deficient fibroblasts, lysine butyrylation was increased. Furthermore, malonyl-CoA decarboxylase (MCD) deficient patient cells had increased levels of malonylated lysines and propionyl-CoA carboxylase (PCC) deficient patient cells had increased propionylation of lysines. Since lysine acylation can greatly impact protein function, aberrant lysine acylation in inherited disorders associated with acyl-CoA accumulation may well play a role in their disease pathophysiology. PMID:24531926

  17. Dorsomedial hindbrain catecholamine regulation of hypothalamic astrocyte glycogen metabolic enzyme protein expression: Impact of estradiol.

    PubMed

    Tamrakar, P; Shrestha, P K; Briski, K P

    2015-04-30

    The brain astrocyte glycogen reservoir is a vital energy reserve and, in the cerebral cortex, subject among other factors to noradrenergic control. The ovarian steroid estradiol potently stimulates nerve cell aerobic respiration, but its role in glial glycogen metabolism during energy homeostasis or mismatched substrate supply/demand is unclear. This study examined the premise that estradiol regulates hypothalamic astrocyte glycogen metabolic enzyme protein expression during normo- and hypoglycemia in vivo through dorsomedial hindbrain catecholamine (CA)-dependent mechanisms. Individual astrocytes identified in situ by glial fibrillary acidic protein immunolabeling were laser-microdissected from the ventromedial hypothalamic (VMH), arcuate hypothalamic (ARH), and paraventricular hypothalamic (PVH) nuclei and the lateral hypothalamic area (LHA) of estradiol (E)- or oil (O)-implanted ovariectomized (OVX) rats after insulin or vehicle injection, and pooled within each site. Stimulation [VMH, LHA] or suppression [PVH, ARH] of basal glycogen synthase (GS) protein expression by E was reversed in the former three sites by caudal fourth ventricular pretreatment with the CA neurotoxin 6-hydroxydopamine (6-OHDA). E diminished glycogen phosphorylase (GP) protein profiles by CA-dependent [VMH, PVH] or -independent mechanisms [LHA]. Insulin-induced hypoglycemia (IIH) increased GS expression in the PVH in OVX+E, but reduced this protein in the PVH, ARH, and LHA in OVX+O. Moreover, IIH augmented GP expression in the VMH, LHA, and ARH in OVX+E and in the ARH in OVX+O, responses that normalized by 6-OHDA. Results demonstrate site-specific effects of E on astrocyte glycogen metabolic enzyme expression in the female rat hypothalamus, and identify locations where dorsomedial hindbrain CA input is required for such action. Evidence that E correspondingly increases and reduces basal GS and GP in the VMH and LHA, but augments the latter protein during IIH suggests that E regulates

  18. 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.

  19. Diets High in Protein or Saturated Fat Do Not Affect Insulin Sensitivity or Plasma Concentrations of Lipids and Lipoproteins in Overweight and Obese Adults123

    PubMed Central

    Chiu, Sally; Williams, Paul T.; Dawson, Taylor; Bergman, Richard N.; Stefanovski, Darko; Watkins, Steven M.; Krauss, Ronald M.

    2014-01-01

    Background: Previous human studies reported inconsistent effects of dietary protein and branched-chain amino acids (BCAAs) on insulin action and glucose metabolism. Similarly, it is unclear whether saturated fat (SF) intake influences these metabolic variables. Objective: The objective of this study was to test the effects of high [30% of energy (%E)] vs. moderate (20%E) intakes of protein (primarily whey) on insulin action and lipid and lipoprotein concentrations in the context of both high (15%E) and low (7%E) SF diets. Methods: The study was conducted as a randomized controlled trial in 158 overweight and obese men and women. After a 4-wk baseline diet [55%E carbohydrate, 15%E protein, 30%E fat (7%E SF)], participants were randomly assigned to 4 wk of either the baseline diet or 1 of 4 test diets containing 35%E carbohydrate and either 20%E or 30%E protein and either 7%E or 15%E SF. Frequently sampled i.v. glucose tolerance tests were administered after each dietary period. Results: Other than significantly higher fasting glucose concentrations for high vs. moderate protein intakes with a low-fat diet (difference ± SE: 0.47 ± 0.14 mmol/L; P = 0.001), there were no significant effects of dietary protein or SF on glucose metabolism, plasma insulin, or concentrations of lipids and lipoproteins. Changes in plasma BCAAs across all diets were negatively correlated with changes in the metabolic clearance rate of insulin (ρ = −0.18, P = 0.03) and positively correlated with changes in the acute insulin response to glucose (ρ = 0.15, P = 0.05). Conclusions: These findings suggest that short-term intake of BCAAs can influence insulin dynamics. However, in this group of overweight and obese individuals, neither high protein nor SF intake affected insulin sensitivity or plasma concentrations of lipids and lipoproteins. This trial was registered at clinicaltrials.gov as NCT00508937. PMID:25332473

  20. Why does offspring size affect performance? Integrating metabolic scaling with life-history theory.

    PubMed

    Pettersen, Amanda K; White, Craig R; Marshall, Dustin J

    2015-11-22

    Within species, larger offspring typically outperform smaller offspring. While the relationship between offspring size and performance is ubiquitous, the cause of this relationship remains elusive. By linking metabolic and life-history theory, we provide a general explanation for why larger offspring perform better than smaller offspring. Using high-throughput respirometry arrays, we link metabolic rate to offspring size in two species of marine bryozoan. We found that metabolism scales allometrically with offspring size in both species: while larger offspring use absolutely more energy than smaller offspring, larger offspring use proportionally less of their maternally derived energy throughout the dependent, non-feeding phase. The increased metabolic efficiency of larger offspring while dependent on maternal investment may explain offspring size effects-larger offspring reach nutritional independence (feed for themselves) with a higher proportion of energy relative to structure than smaller offspring. These findings offer a potentially universal explanation for why larger offspring tend to perform better than smaller offspring but studies on other taxa are needed.

  1. Why does offspring size affect performance? Integrating metabolic scaling with life-history theory.

    PubMed

    Pettersen, Amanda K; White, Craig R; Marshall, Dustin J

    2015-11-22

    Within species, larger offspring typically outperform smaller offspring. While the relationship between offspring size and performance is ubiquitous, the cause of this relationship remains elusive. By linking metabolic and life-history theory, we provide a general explanation for why larger offspring perform better than smaller offspring. Using high-throughput respirometry arrays, we link metabolic rate to offspring size in two species of marine bryozoan. We found that metabolism scales allometrically with offspring size in both species: while larger offspring use absolutely more energy than smaller offspring, larger offspring use proportionally less of their maternally derived energy throughout the dependent, non-feeding phase. The increased metabolic efficiency of larger offspring while dependent on maternal investment may explain offspring size effects-larger offspring reach nutritional independence (feed for themselves) with a higher proportion of energy relative to structure than smaller offspring. These findings offer a potentially universal explanation for why larger offspring tend to perform better than smaller offspring but studies on other taxa are needed. PMID:26559952

  2. CtIP: A DNA damage response protein at the intersection of DNA metabolism.

    PubMed

    Makharashvili, Nodar; Paull, Tanya T

    2015-08-01

    The mammalian CtIP protein and its orthologs in other eukaryotes promote the resection of DNA double-strand breaks and are essential for meiotic recombination. Here we review the current literature supporting the role of CtIP in DNA end processing and the importance of CtIP endonuclease activity in DNA repair. We also examine the regulation of CtIP function by post-translational modifications, and its involvement in transcription- and replication-dependent functions through association with other protein complexes. The tumor suppressor function of CtIP likely is dependent on a combination of these roles in many aspects of DNA metabolism.

  3. Feeding modality affects muscle protein deposition by influencing protein synthesis, but not degradation in muscle of neonatal pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Neonatal pigs can serve as dual-use models for nutrition research in animal agriculture and biomedical fields. To determine how feeding modality by either intermittent bolus or continuous schedule affects protein anabolism and catabolism, neonatal pigs (n = 6/group, 9-d-old) were overnight fasted (F...

  4. APL-1, the Alzheimer's Amyloid precursor protein in Caenorhabditis elegans, modulates multiple metabolic pathways throughout development.

    PubMed

    Ewald, Collin Y; Raps, Daniel A; Li, Chris

    2012-06-01

    Mutations in the amyloid precursor protein (APP) gene or in genes that process APP are correlated with familial Alzheimer's disease (AD). The biological function of APP remains unclear. APP is a transmembrane protein that can be sequentially cleaved by different secretases to yield multiple fragments, which can potentially act as signaling molecules. Caenorhabditis elegans encodes one APP-related protein, APL-1, which is essential for viability. Here, we show that APL-1 signaling is dependent on the activity of the FOXO transcription factor DAF-16 and the nuclear hormone receptor DAF-12 and influences metabolic pathways such as developmental progression, body size, and egg-laying rate. Furthermore, apl-1(yn5) mutants, which produce high levels of the extracellular APL-1 fragment, show an incompletely penetrant temperature-sensitive embryonic lethality. In a genetic screen to isolate mutants in which the apl-1(yn5) lethality rate is modified, we identified a suppressor mutation in MOA-1/R155.2, a receptor-protein tyrosine phosphatase, and an enhancer mutation in MOA-2/B0495.6, a protein involved in receptor-mediated endocytosis. Knockdown of apl-1 in an apl-1(yn5) background caused lethality and molting defects at all larval stages, suggesting that apl-1 is required for each transitional molt. We suggest that signaling of the released APL-1 fragment modulates multiple metabolic states and that APL-1 is required throughout development.

  5. Myocardial Reloading after Extracorporeal Membrane Oxygenation Alters Substrate Metabolism While Promoting Protein Synthesis

    SciTech Connect

    Kajimoto, Masaki; Priddy, Colleen M.; Ledee, Dolena; Xu, Chun; Isern, Nancy G.; Olson, Aaron; Des Rosiers, Christine; Portman, Michael A.

    2013-08-19

    Extracorporeal membrane oxygenation (ECMO) unloads the heart providing a bridge to recovery in children after myocardial stunning. Mortality after ECMO remains high.Cardiac substrate and amino acid requirements upon weaning are unknown and may impact recovery. We assessed the hypothesis that ventricular reloading modulates both substrate entry into the citric acid cycle (CAC) and myocardial protein synthesis. Fourteen immature piglets (7.8-15.6 kg) were separated into 2 groups based on ventricular loading status: 8 hour-ECMO (UNLOAD) and post-wean from ECMO (RELOAD). We infused [2-13C]-pyruvate as an oxidative substrate and [13C6]-L-leucine, as a tracer of amino acid oxidation and protein synthesis into the coronary artery. RELOAD showed marked elevations in myocardial oxygen consumption above baseline and UNLOAD. Pyruvate uptake was markedly increased though RELOAD decreased pyruvate contribution to oxidative CAC metabolism.RELOAD also increased absolute concentrations of all CAC intermediates, while maintaining or increasing 13C-molar percent enrichment. RELOAD also significantly increased cardiac fractional protein synthesis rates by >70% over UNLOAD. Conclusions: RELOAD produced high energy metabolic requirement and rebound protein synthesis. Relative pyruvate decarboxylation decreased with RELOAD while promoting anaplerotic pyruvate carboxylation and amino acid incorporation into protein rather than to the CAC for oxidation. These perturbations may serve as therapeutic targets to improve contractile function after ECMO.

  6. Using comparative genomics to uncover new kinds of protein-based metabolic organelles in bacteria

    PubMed Central

    Jorda, Julien; Lopez, David; Wheatley, Nicole M; Yeates, Todd O

    2013-01-01

    Bacterial microcompartment (MCP) organelles are cytosolic, polyhedral structures consisting of a thin protein shell and a series of encapsulated, sequentially acting enzymes. To date, different microcompartments carrying out three distinct types of metabolic processes have been characterized experimentally in various bacteria. In the present work, we use comparative genomics to explore the existence of yet uncharacterized microcompartments encapsulating a b